Heat-stable enterotoxin inhibits intestinal stem cell expansion to disrupt the intestinal integrity by downregulating the Wnt/ß-catenin pathway.

Enterotoxigenic Escherichia coli causes severe infectious diarrhea with high morbidity and mortality in newborn and weanling pigs mainly through the production of heat-stable enterotoxins (STs). However, the precise regulatory mechanisms involved in ST-induced intestinal epithelium injury remain unclear. Consequently, we conducted the experiments in vivo (mice), ex vivo (mouse and porcine enteroids), and in vitro (MODE-K and IPEC-J2 cells) to explore the effect of STp (one type of STa) on the integrity of the intestinal epithelium. The results showed that acute STp exposure led to small intestinal edema, disrupted intestinal integrity, induced crypt cell expansion into spheroids, and downregulated Wnt/ß-catenin activity in the mice. Following a similar trend, the enteroid-budding efficiency and the expression of Active ß-catenin, ß-catenin, Lgr5, PCNA, and KRT20 were significantly decreased after STp treatment, as determined ex vivo. In addition, STp inhibited cell proliferation, induced cell apoptosis, destroyed cell barriers, and reduced Wnt/ß-catenin activity by downregulating its membrane receptor Frizzled7 (FZD7). In contrast, Wnt/ß-catenin reactivation protected the IPEC-J2 cells from STp-induced injury. Taking these findings together, we conclude that STp inhibits intestinal stem cell expansion to disrupt the integrity of the intestinal mucosa through the downregulation of the Wnt/ß-catenin signaling pathway.

Evaluation of the apolipoprotein E (apoE)-HDL-associated risk factors for coronary heart disease using duo-functional electrochemical aptasensor.

Apolipoprotein E containing high-density lipoprotein (apoE-HDL) and apoE-HDL cholesterol (apoE-HDL-C) are recently recognized as potential biomarkers for coronary heart disease (CHD). We herein developed a two-stage, enzyme-assisted, dual-signal aptasensor that enables a useful electrochemical sensing platform for simultaneous determination of apoE-HDL, apoE-HDL-C, and total HDL-C presented in the sample. The detection scheme consists of two subsystems. In subsystem (I), the level of apoE-HDL is evaluated upon the binding of apoE-specific aptamer and subsequently methylene blue (MB)-labeled DNA displacement occurs on the electrode surface, resulting in electrochemical reduction of methylene blue. In subsystem (II), two kinds of cholesterol levels (apoE-HDL-C and total HDL-C) can be measured. For apoE-HDL-C, the amount of cholesterol in apoE-HDL captured by the aptamer in the first step can be further determined with the aid of surfactant, cholesterol esterase, cholesterol oxidase, and p-aminophenol-mediated electrochemical signal amplification. As for total HDL-C, the amount of cholesterol is determined by the same approach as that used for apoE-HDL-C determination, but without washing (separation). The linear dynamic range for apoE-HDL determination is from 1 to 100 mg/dL (R2 = 1.00). For cholesterol standards, the linear dynamic range is determined to be 0-250 mg/dL (R2 = 0.98). Finally, serial dilutions of purified human HDL preparations were examined using the newly developed aptasensor; the percentage of apoE-HDL-C to HDL-C was found to be ~10%, which correlated well with previously reported values. In conclusion, we successfully developed an electrochemical aptasensor that allows concurrent quantification of apoE-HDL, apoE-HDL-C, and HDL-C on the same platform, offering an efficient, convenient, and purification-free sensing strategy for predictive CHD biomarkers.

T-lymphoma invasion and metastasis 1 promotes invadopodia formation and is regulated by the PI3K/Akt signaling pathway in hepatocellular carcinoma.

At present, there are still many poorly understood aspects of the mechanisms underlying hepatocellular carcinoma (HCC) invasion and metastasis. Invadopodia are important structures for cancer cell invasion and metastasis. We determined that high T-lymphoma invasion and metastasis 1 (Tiam1) expression is associated with HCC invasion and metastasis and poor patient prognosis after surgery. Gain- and loss-of-function studies confirmed that Tiam1 promotes invadopodia formation in HCC by activating Rac1. A series of biochemical experiments confirmed that this effect is regulated by the PI3K/Akt signaling pathway. We also confirmed that PIP2 facilitates this effect. In summary, these findings reveal that Tiam1 plays an important role in invadopodia formation in HCC.

Open reduction and locked compression plate fixation, with or without allograft strut, for periprosthetic fractures in patients who had a well-fixed femoral stem: a retrospective study with an average 2-year follow-up.

BACKGROUND: The use of cortical strut allograft has not been determined for Vancouver type B1 or C fracture. This study aimed to evaluate the short-term efficacy of locking compression plating with or without cortical strut allograft in managing these types of fractures. METHODS: We retrospectively assessed 32 patients (17 males, 15 females; 23-88 years, mean: 67.2 years) with Vancouver type B1 or C fractures. Seventeen patients (Group A; B1 fractures in 15 hips, C fractures in 2 hips) were treated with open reduction and internal fixation with locking compression plates (group A). The other 15 patients (Group B; B1 in 14 hips, C in 1 hip) were fixed by locking compression plating combined with cortical strut allografting (group B). The fracture healing rate, healing time, complications and function were compared between these two groups. RESULTS: The mean follow-up time was 32.4 months (12 to 66), and the overall fracture union rate of the 32 patients was 96.9%. Group B had a higher fracture union rate than Group A, but the difference was not statistically significant. Group A had one case of nonunion of type B1 fracture and one case of malunion; the mean time to fracture healing was 5.3 months (3 to 9). In group B, all patients reached bony union without malunion, with a mean time of fracture healing of 5.1 months (3 to 8). CONCLUSION: Treatment of Vancouver type B1 or C fractures by locking compression plating, with or without cortical strut allografting, resulted in similar union rates in these patients. This suggest that, the use of cortical strut allografting should be decided cautiously.

Gaze Tracking Based on Concatenating Spatial-Temporal Features.

Based on experimental observations, there is a correlation between time and consecutive gaze positions in visual behaviors. Previous studies on gaze point estimation usually use images as the input for model trainings without taking into account the sequence relationship between image data. In addition to the spatial features, the temporal features are considered to improve the accuracy in this paper by using videos instead of images as the input data. To be able to capture spatial and temporal features at the same time, the convolutional neural network (CNN) and long short-term memory (LSTM) network are introduced to build a training model. In this way, CNN is used to extract the spatial features, and LSTM correlates temporal features. This paper presents a CNN Concatenating LSTM network (CCLN) that concatenates spatial and temporal features to improve the performance of gaze estimation in the case of time-series videos as the input training data. In addition, the proposed model can be optimized by exploring the numbers of LSTM layers, the influence of batch normalization (BN) and global average pooling layer (GAP) on CCLN. It is generally believed that larger amounts of training data will lead to better models. To provide data for training and prediction, we propose a method for constructing datasets of video for gaze point estimation. The issues are studied, including the effectiveness of different commonly used general models and the impact of transfer learning. Through exhaustive evaluation, it has been proved that the proposed method achieves a better prediction accuracy than the existing CNN-based methods. Finally, 93.1% of the best model and 92.6% of the general model MobileNet are obtained.

p53 haploinsufficiency and increased mTOR signalling define a subset of aggressive hepatocellular carcinoma.

BACKGROUND & AIMS: p53 mutations occur frequently in human HCC. Activation of the mammalian target of rapamycin (mTOR) pathway is also associated with HCC. However, it is still unknown whether these changes together initiate HCC and can be targeted as a potential therapeutic strategy. METHODS: We generated mouse models in which mTOR was hyperactivated by loss of tuberous sclerosis complex 1 (Tsc1) with or without p53 haplodeficiency. Primary cells were isolated from mouse livers. Oncogenic signalling was assessed in vitro and in vivo, with or without targeted inhibition of a single molecule or multiple molecules. Transcriptional profiling was used to identify biomarkers predictive of HCC. Human HCC materials were used to corroborate the findings from mouse models. RESULTS: p53 haploinsufficiency facilitates mTOR signalling via the PTEN/PI3K/Akt axis, promoting HCC tumorigenesis and lung metastasis. Inhibition of PI3K/Akt reduced mTOR activity, which effectively enhanced the anticancer effort of an mTOR inhibitor. ATP-binding cassette subfamily C member 4 (Abcc4) was found to be responsible for p53 haploinsufficiency- and Tsc1 loss-driven HCC tumorigenesis. Moreover, in clinical HCC samples, Abcc4 was specifically identified an aggressive subtype. The mTOR inhibitor rapamycin significantly reduced hepatocarcinogenesis triggered by Tsc1 loss and p53 haploinsufficiency in vivo, as well as the biomarker Abcc4. CONCLUSIONS: Our data advance the current understanding of the activation of the PTEN/PI3K/Akt/mTOR axis and its downstream target Abcc4 in hepatocarcinogenesis driven by p53 reduction and Tsc1 loss. Targeting mTOR, an unexpected vulnerability in p53 (haplo)deficiency HCC, can be exploited therapeutically to treat Abcc4-positive patients with HCC. LAY SUMMARY: Tsc1 loss facilitates the p53 (haplo)insufficiency-mediated activation of the PTEN/Akt/mTOR axis, leading to the elevated expression of Abcc4 to drive HCC tumorigenesis and metastasis in mice. Inhibition of mTOR protects against p53 haploinsufficiency and Tsc1 loss-triggered tumour-promoting activity, providing a new approach for treating an aggressive subtype of HCC exhibiting high Abcc4 expression.

Numerical investigation of the solute dispersion in finite-length microchannels with the interphase transport.

This paper utilizes a combined approach of the convection-diffusion theory and the moment analysis to conduct a comprehensive investigation of the solute dispersion under the influence of the interphase transport in finitely long inner coated microchannels. The present work has threefold novel contributions: (1) The 2D solute concentration contours in the stationary phase are calculated for the first time to facilitate the understanding the role of the interphase transport in the solute dispersion in the mobile phase. (2) The skewness of the elution curves is investigated to guide the control of solute band shape at the channel outlet. (3) The 2D diffusion-convection theory and zero-dimensional (0D) moment analysis complement each other to present a characterization of the solute dispersion behaviors more comprehensive than that by either of the two methods alone. Parametric studies are performed to clarify the effects of four major parameters related to the interphase transport (i.e., stationary phase Péclet number, interphase transport rate, partition coefficient, and stationary phase thickness) on the solute dispersion characteristics. The results from this study provide a straightforward understanding of the effects of interphase transport on the solute dispersion in finitely long microchannels and are of potential relevance to the design and operation of the microfluidics-based analytical devices.

Wnt/ß-catenin-mediated heat exposure inhibits intestinal epithelial cell proliferation and stem cell expansion through endoplasmic reticulum stress.

Heat stress induced by continuous high ambient temperatures or strenuous exercise in humans and animals leads to intestinal epithelial damage through the induction of intracellular stress response. However, the precise mechanisms involved in the regulation of intestinal epithelial cell injury, especially intestinal stem cells (ISCs), remain unclear. Thereby, in vitro a confluent monolayer of IPEC-J2 cells was exposed to the high temperatures (39, 40, and 41°C), the IPEC-J2 cell proliferation, apoptosis, differentiation, and barrier were determined, as well as the expression of GRP78, which is a marker protein of endoplasmic reticulum stress (ERS). The Wnt/ß-catenin pathway-mediated regenerative response was validated using R-spondin 1 (Rspo1). And ex-vivo, three-dimensional cultured enteroids were developed from piglet jejunal crypt and employed to assess the ISC activity under heat exposure. The results showed that exposure to 41°C for 72 hr, rather than 39°C and 40°C, decreased IPEC-J2 cell viability, inhibited cell proliferation and differentiation, induced ERS and cell apoptosis, damaged barrier function and restricted the Wnt/ß-catenin pathway. Nevertheless, Wnt/ß-catenin reactivation via Rspo1 protects the intestinal epithelium from heat exposure-induced injury. Furthermore, exposure to 41°C for 24 hr reduced ISC activity, stimulated crypt-cell apoptosis, upregulated the expression of GRP78 and caspase-3, and downregulated the expression of ß-catenin, Lgr5, Bmi1, Ki67, KRT20, ZO-1, occludin, and claudin-1. Taken together, we conclude that heat exposure induces ERS and downregulates the Wnt/ß-catenin signaling pathway to disrupt epithelial integrity by inhibiting the intestinal epithelial cell proliferation and stem cell expansion.

Tin(ii)-catalyzed dehydrative cross-coupling of 2H-chromene hemiacetals with ketones.

A dehydrative cross-coupling of 2H-chromene hemiacetals with ketones is described. Without the derivatization of 2H-chromene hemiacetals to 2H-chromene acetals, the direct C-OH/C-H coupling reaction has been accomplished with water as the only by-product. With the use of Sn(OTf)2 as the promoter, the reaction goes smoothly under mild conditions.

Electrokinetic power generation in conical nanochannels: regulation effects due to conicity.

Electrokinetic power generation is a promising clean energy production technology, which utilizes the electric double layer in a nanochannel to convert the hydrodynamic energy to electrical power. Previous research largely focused on electrokinetic power generation in nanochannels with a uniform cross-section. In this work, we perform a systematic investigation of electrokinetic power generation in a conical nanochannel. For this purpose, a multiphysical model consisting of the Planck-Nernst-Poisson equations and the Navier-Stokes equation is formulated and solved numerically. In particular, we discover various regulation effects in electrokinetic power generation in conical nanochannels, which manifest as the difference in the power generation characteristics (streaming potential, streaming current and current-voltage relationship) between two opposite pressure differences of the same magnitude. These regulation effects are found to originate from the conicity of the nanochannel. Furthermore, the regulation parameters are defined to quantify the observed regulation effects. Various regulation parameters can be up to severals tens of percent under extreme conditions (e.g., large pressure difference, high surface charge density or large conicity), indicating the substantial significance of the regulation effects in electrokinetic power generation. The conclusions from this work can serve as an important reference for the design and operation of nanofluidic electrokinetic power generation devices.

mTORC1 signaling activation increases intestinal stem cell activity and promotes epithelial cell proliferation.

The crypt-villus axis of the intestine undergoes a continuous renewal process that is driven by intestinal stem cells (ISCs). However, the homeostasis is disturbed under constant exposure to high ambient temperatures, and the precise mechanism is unclear. We found that both EdU+ and Ki67+ cell ratios were significantly reduced after exposure to 41°C, as well as the protein synthesis rate of IPEC-J2 cells, and the expression of ubiquitin and heat shock protein 60, 70, and 90 were significantly increased. Additionally, heat exposure decreased enteroid expansion and budding efficiency, as well as induced apoptosis after 48 hr; however, no significant difference was observed in the apoptosis ratio after 24 hr. In the process of heat exposure, the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway was significantly inhibited in both IPEC-J2 cells and enteroids. Correspondingly, treatment of IPEC-J2 and enteroids with the mTORC1 agonist MHY1485 at 41°C significantly attenuated the inhibition of proliferation and protein synthesis, increased the ISC activity, and promoted expansion and budding of enteroid. In summary, we conclude that the mTORC1 signaling pathway regulates intestinal epithelial cell and stem cell activity during heat exposure-induced injury.

Circadian genes period1b and period2 differentially regulate inflammatory responses in zebrafish.

The circadian clock has been shown to regulate various immune processes in different animals. Our previous report demonstrated that the innate immune responses in zebrafish show significant rhythmicity that could be regulated by melatonin. Here, we used diurnal zebrafish to determine the role of circadian genes in the inflammatory responses. Our results indicate that circadian genes exhibit rhythmic oscillations in zebrafish leukocytes, and mutations of the clock genes period1b (per1b) and period2 (per2) considerably affect these oscillations. Using a wounded zebrafish inflammation model, we found that under constant dark conditions (DD), the expression of pro-inflammatory cytokines is significantly downregulated in per1b gene mutant zebrafish and significantly upregulated in the per2 gene mutant zebrafish. Furthermore, using real-time imaging technology, we found that the per1b gene markedly disturbs the rhythmic recruitment of neutrophils toward the injury, whereas the per2 gene does not show a significant effect. Taken together, our results reveal differential functions of the circadian genes per1b and per2 in the inflammatory responses, serving as evidence that circadian rhythms play a vital role in immune processes.

Asymmetric total synthesis of talienbisflavan A.

The first asymmetric total syntheses of talienbisflavan A and bis-8,8'-epicatechinylmethane as well as a facile synthesis of bis-8,8'-catechinylmethane has been accomplished from readily available starting materials by using a newly developed direct regioselective methylenation of catechin derivatives as one of the key steps.

Prostate cancer with elevated free prostate-specific antigen density: A case report.

BACKGROUND: Prostate cancer is the second most common cancer among men worldwide, and prostate-specific antigen (PSA) is often used in clinical practice to screen for prostate cancer. Normal total PSA (tPSA) level initially excludes prostate cancer. Here, we report a case of prostate cancer with elevated free PSA density (fPSAD). CASE SUMMARY: A patient diagnosed with benign prostatic hyperplasia underwent prostatectomy, and the postoperative pathological results showed acinar adenocarcinoma of the prostate. The patient is currently undergoing endocrine chemotherapy. CONCLUSION: We provide a clinical reference for diagnosis and treatment of patients with normal tPSA but elevated fPSAD.

2-Methyl-4'-(methylthio)-2-morpholinopropiophenone: A commercial photoinitiator being used as a new psychoactive substance.

Synthetic cathinones, which are novel psychoactive substances, have caused major social problems worldwide. A substance called 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MMMP), which is employed as a commercial industrial photoinitiator for triggering polymerization, has a basic cathinone backbone; however, few reports regarding MMMP have been published. In the current study, three potential metabolites of MMMP-namely hydroxy-MMMP (HO-MMMP), HO-MMMP-sulfoxide (HO-MMMP-SO), and HO-MMMP-sulfone (HO-MMMP-SO2)-were successfully synthesized, and MMMP and these three potential metabolites were used as standards to establish an analytic method based on liquid chromatography-tandem mass spectrometry for the quantitative analysis of urine. This analytic method and related parameters-including dynamic range, limit of quantification, selectivity, precision, accuracy, carryover effect, matrix effect, interference, and dilution integrity-were optimized and validated. Forty urine samples from 1,691 individuals who abused drugs were determined to contain MMMP, HO-MMMP, HO-MMMP-SO, or HO-MMMP-SO2; the results of this study indicate that approximately 2.37 % of drug abusers in Taiwan consumed MMMP in 2023. These 40 urine samples were analyzed to investigate the metabolism of MMMP in humans. The results indicate that HO-MMMP-SO is the main metabolite in human urine. This study recommends HO-MMMP-SO with a concentration of 2 ng/mL as a target and cutoff value, respectively, for identifying individuals who have consumed MMMP.

Anti-deadzone adaptive fuzzy dynamic surface control for planar space robot with elastic base and flexible links.

In order to combat the impact of the dead zone and reduce vibration of the space robot's elastic base and flexible links, the trajectory tracking and vibration suppression of a multi-flexible-link free-floating space robot system are addressed. First, the elastic connection between the base and the link is considered as a linear spring. Then the assumed mode approach is used to derive the dynamic model of the flexible system. Secondly, a slow subsystem characterizing the rigid motion and a fast subsystem relating to vibration of the elastic base and multiple flexible links are generated utilizing two-time scale hypotheses of singular perturbation. For the slow subsystem with a dead zone in joint input torque, a dynamic surface control method with adaptive fuzzy approximator is designed. Dynamic surface control scheme is adopted to avoid calculation expansion and to simplify calculation. The fuzzy logic function is applied to approximate uncertain terms of the dynamic equation including the dead zone errors. For the fast subsystem, an optimal linear quadratic regulator controller is used to suppress the vibration of the multiple flexible links and elastic base, ensuring the stability and tracking accuracy of the system. Lastly, the simulation results verify the effectiveness of the proposed control strategy.

[Progress on breeding for best-hybridized crossing of meat rabbits].

Best-hybridized crossing should ideally result in optimal exploitation of heterosis of lines and capitalize on expressed heterosis. Rabbit breeding is heading in the direction of breeding for best-hybridized crossing of meat rabbits. Most special sire lines are selected for post-weaning average daily gain and marketing weight. Post-weaning growth has a negative and favorable genetic correlation with the feed conversion ratio, which is used in indirect selection for feed conversion ratio. The most common selection criteria for special maternal lines are related to litter size at birth or at weaning. Since the heritability of most reproductive traits is low, we must collect as many individual and relative records as possible in the genetic evaluation of rabbits. The BLUP procedure under an animal repeatability model is the most common procedure used for evaluation of animals in selection programs for special lines of meat rabbits. Direct selection for litter size is less efficient than selection for post-weaning growth, but the estimation of heterosis is generally higher for litter size than that for the post-weaning growth. Evaluation of heterosis could be performed by estimating crossbreeding parameters in the cross or comparing contemporary productivity among purebreds and crossbreds. Here, we reviewed breeding of special lines, exploitation of heterosis of crossbreds, and establishment of crossbreeding system of hybrid meat rabbits and summarized the methodologies of breeding special lines, criteria in selection programs, and the result of heterosis estimates.

Cepharanthine hydrochloride inhibits the Wnt/ß­catenin/Hedgehog signaling axis in liver cancer.

Cepharanthine, a biscoclaurine alkaloid isolated from the roots of Stephania cephalantha Hayata, has been reported to demonstrate antitumor activity across multiple cancer types; however, the mechanisms are still under investigation. High transcriptional responses by both the Hedgehog and Wnt pathways are frequently associated with specific human cancers, including liver cancer. To investigate whether these signaling pathways are involved in the pharmaceutical action of cepharanthine, we investigated Hedgehog and Wnt signaling in models of liver cancer treated with a semi­synthetic cepharanthine derivative, cepharanthine hydrochloride (CH), in vitro and in vivo. By using MTT cytotoxic, scratch, Transwell, colony formation and flow cytometry assays, the pharmaceutical effect of CH was assessed. The compound was found to inhibit cellular proliferation and invasion, and promote apoptosis. Subsequent mechanistic investigations revealed that CH suppressed the Hedgehog/Gli1 signaling pathway by inhibiting Gli1 transcription and its transcriptional activity. CH also inhibited Wnt/ß­catenin signaling, and the pathway was found to be an upstream regulator of Hedgehog signaling in CH­treated liver cancer cells. Finally, the antitumor effects of CH were demonstrated in an in vivo xenograft tumor model. Immunohistochemical analysis indicated that Gli1 protein levels were diminished in CH­treated xenografts, compared with that noted in the controls. In summary, our results highlight a novel pharmaceutical antitumor mechanism of cepharanthine and provide support for CH as a clinical therapy for refractory liver cancer and other Wnt/Hedgehog­driven cancers.

Identification of a novel norketamine precursor from seized powders: 2-(2-chlorophenyl)-2-nitrocyclohexanone.

The identification of new psychoactive substances (NPSs) and their precursors is crucial to understand trends in NPSs so that they can be regulated before they pose a serious threat to human health. In this case, 24 bags containing approximately 600 kg of yellow powder were seized; the smugglers had been monitored for 3 years by the officers of Taiwan's Ministry of Justice Investigation Bureau. A handheld Raman analyzer yielded a positive result for N-boc norketamine; thus, the seized powder was sent to this laboratory for confirmation through gas chromatography-mass spectrometry, liquid chromatographyhigh-resolution mass spectrometry, proton nuclear magnetic resonance (1H NMR), carbon-13 nuclear magnetic resonance (13C NMR), two-dimensional correlation NMR measurements (2D_COSY), heteronuclear single-quantum correlation NMR measurements (2D_HSQC), and single-crystal X-ray diffraction. This thermolabile powder was subsequently identified as 2-(2-chlorophenyl)- 2-nitrocyclohexanone (2-CPNCH), which can be employed as a precursor for the synthesis of norketamine and is available commercially. Norketamine has similar pharmacological effects to ketamine and phencyclidine but is not regulated in many countries. In this case report, mass fragments, 1H NMR, 13C NMR, 2D_COSY, and 2D_HSQC data of 2-CPNCH are presented; moreover, how criminals exploit the loopholes in the law for conducting unauthorized drug manufacturing is discussed.

New ketamine analogue: 2-fluorodeschloro-N-ethyl-ketamine and its suggested metabolites.

Identifying new psychoactive substances (NPSs) and their metabolites is essential for regulating such substances for purposes of law enforcement and forensics. NPSs can be regulated on the basis of their chemical structures before they become a critical threat to society. Further, NPS metabolites can be targeted for analysis in urine, blood, and hair. This case study reports an incident in which 10 bags with approximately 15 g of crystalline material were seized from suspects by law enforcement officers and sent to the laboratory for confirmation. Gas chromatography-mass spectrometry, liquid chromatography-high-resolution mass spectrometry, and nuclear magnetic resonance (NMR) were employed to analyze these materials. The analyses revealed that the materials were a new ketamine analog, 2-fluorodeschloro-N-ethyl-ketamine (2-FDCNEK). Single-crystal X-ray diffraction (SXRD) analysis was also employed to confirm this result. In addition, metabolites of 2-FDCNEK were investigated using a fungal model and a urine sample from an abuser. The results suggest that 2-FDCNEK and 2-fluorodeschoro-norketamine are optimal metabolites for biological samples. This report presents the mass fragmentation, NMR analysis, and SXRD data of 2-FDCNEK. In addition, it provides suggestions regarding metabolites of 2-FDCNEK for law enforcement and forensic purposes, thereby facilitating the detection of this new ketamine analog.