L-theanine is an important natural non-protein amino acid that is widely used in food and medicine. Although in previous studies, a microbial fermentation method for L-theanine without the addition of ethylamine has been developed, the conversion rate of this process needs to be further improved. In this study, we constructed a de novo synthesis pathway of L-theanine with glucose as the substrate. First, an in vitro transformation pathway containing ω-transaminase (TA) and γ-glutamylmethylamide synthetase (GMAS) was designed, optimized, and introduced into the chassis strain Escherichia coli K12 W3110 to achieve de novo synthesis of L-theanine. To improve the synthesis efficiency through metabolic engineering, we increased the copies of the GMAS gene gams and the TA gene spuC and enhanced the expression of the aldehyde dehydrogenase gene eutE to provide sufficient acetaldehyde substrate, knocked out the lactate dehydrogenase gene ldhA and the pyruvate formate lyase gene pflB to block bypass metabolism, and introduced the alanine dehydrogenase gene alD to recycle alanine. Furthermore, we over-expressed the phosphoenolpyruvate carboxylase gene ppc to enhance the carbon flux of the TCA cycle, knocked out the succinyl-CoA synthase gene sucCD to reduce the loss of downstream flux of TCA, and integrated the glutamate dehydrogenase gene gdh to enhance the supply of L-glutamate. Finally, the polyphosphate kinase gene ppk was introduced to the ATP cycle, which enhanced the energy supply in L-theanine production. The recombinant strain Tea11 produced 22.60 g/L L-theanine in a 5 L fermenter in 28 h, with a conversion rate of 41.71%. This synthetic pathway in this study balanced the relationship between the supply of ethylamine and the production of theanine, providing a new idea for metabolic engineering of microorganisms to produce L-theanine.
Glutamates/biosynthesis* ; Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Fermentation ; Transaminases/metabolism* ; Amide Synthases/metabolism* ; Glucose/metabolism*

Objective To analyze the relationship between the expression levels of serum microRNA-214-3p and miR-124-3p with the severity of Parkinson's disease(PD),and their early diagnostic value.Methods From January 2018 to December 2023,96 PD patients admitted to Rugao Traditional Chinese Medicine Hospital were selected as the PD group,and 106 healthy individuals were selected as the control group.According to the severity of 96 patients,they were grouped into the early stage group(I-II stage,n=59)and the mid to late stage group(III-V stage,n=37).RT-qPCR was applied to detect serum levels of miR-214-3p and miR-124-3p.Spearman method was used for correlation analysis.The influencing factors of PD severity were analyzed using multiple Logistic regression analysis.The efficacy of serum miR-214-3p and miR-124-3p in diagnosing PD and its severity was analyzed by receiver operating characteristics(ROC).Results Compared with the control group,the serum levels of miR-214-3p and miR-124-3p were lower in the PD group(P＜0.05).Compared with the early stage group,there were a longer disease course,higher level of homocysteine(Hcy)and lower levels of serum miR-214-3p and miR-124-3p in the mid to late stage group(P＜0.05).Spearman analysis showed that serum miR-214-3p and miR-124-3p were negatively correlated with Hoehn-Yahr staging in PD patients(P＜0.05).Multivariate Logistic regression showed that disease duration(OR=1.249),Hcy(OR=1.156),serum miR-214-3p(OR=0.925)and miR-124-3p(OR=0.917)were factors influencing the severity of PD(P＜0.05).ROC analysis showed that the sensitivity and specificity of serum miR-214-3p and miR-124-3p combined in the diagnosis of PD were 85.42%and 81.90%respectively.The sensitivity and specificity of serum miR-214-3p and miR-124-3p in the diagnosis of advanced PD were 89.16%and 79.66%respectively.Conclusion The serum levels of miR-214-3p and miR-124-3p are relatively low in PD patients,and their levels are related to the severity of disease.The detection of serum miR-214-3p and miR-124-3p is helpful for the diagnosis and evaluation of PD.

Megestrol acetate is widely used in clinical practice and offers benefits to patients. However, it carries potential adverse effects, such as hypoadrenocorticism, which is often overlooked due to its atypical clinical manifestations. This report describes two cases of megestrol acetate-induced hypoadrenocorticism. Through a review of relevant literature, the mechanisms, clinical characteristics, and treatment strategies are summarized to enhance clinicians′ awareness of this potential complication.

Objective:To explore the effect of long noncoding RNA ANK3DT (lncRNA ANK3DT) on DNA damage repair ability and radiosensitivity of cervical cancer HeLa cells.Methods:The effect of lncRNA ANK3DT on the repair efficiency of DNA double-strand breaks (DSBs) was analyzed by the pre-constructed quantitative assay system based on the CRISPR/Cas9 system targeting homologous recombination (HR) and non-homologous end-joining (NHEJ) repair. Clone formation assay, flow cytometry, and immunofluorescence were used to detect the effects of down-regulation of lncRNA ANK3DT on cellular radiosensitivity, apoptosis and G 2/M phase arrest, and DSB repair after X-ray irradiation. Western blot, qPCR, and dual fluorokinase reporter gene plasmid was used to detect the effects of lncRNA ANK3DT on the HR repair-related protein CtIP expression and transcriptional regulation. Results:Down-regulation of lncRNA ANK3DT significantly inhibited HR repair and had no effect on NHEJ repair. The expression of lncRNA ANK3DT was significantly increased in HeLa cells at 24, 48, 72 h after X-ray irradiation ( t=-23.39, -88.83, -52.42, P<0.05). Down-regulation of lncRNA ANK3DT inhibited X-ray-induced DSB repair and increased apoptosis levels ( t=-14.63, P <0.05), prolonged G 2/M phase block ( t=-19.50, P <0.05), increased the radiosensitivity of HeLa cells (radiosensitization ratio=1.21), inhibited the CtIP promoter activity and decreased its mRNA and protein expression. Conclusions:lncRNA ANK3DT affects HR repair by regulating CtIP transcription, and down-regulation of lncRNA ANK3DT increases the radiosensitivity of HeLa cells by inhibiting DSB repair after ionizing radiation.

Objective:To develop a novel fibroblast activation protein (FAP) cyclic peptide imaging agent, Al 18F-FAP-NOX, evaluate its in vitro and in vivo properties, and explore its feasibility of PET/CT imaging in tumors with FAP positive expression. Methods:Al 18F-FAP-NOX was manually synthesized. The in vitro stability of Al 18F-FAP-NOX was determined using radio high performance liquid chromatography (HPLC). The lipid water partition coefficient log P, in vitro cell uptake experiments, microPET/CT imaging and biodistribution in 293T-FAP tumor-bearing mice were conducted to preliminarily evaluate the pharmacokinetics and biological efficacy of Al 18F-FAP-NOX. Afterwards, a patient (male, 65 years old) with lung cancer underwent Al 18F-FAP-NOX PET/CT imaging. Results:Al 18F-FAP-NOX was successfully synthesized with a yield of (26.28±2.31)% without attenuation correction ( n=4), and the radiochemical purity was more than 95%. Al 18F-FAP-NOX exhibited good stability and hydrophilicity (log P=-3.02±0.08, n=5). In cell assays, the uptake of Al 18F-FAP-NOX in HT1080-FAP cells reached the plateau phase at 15 min ((7.31±0.53) percentage activity of injection dose per million cells (%ID/mio cells)), exhibiting high cellular uptake. The uptake of Al 18F-FAP-NOX could be significantly inhibited by 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)-FAP-2286. The microPET/CT results of 293T-FAP tumor-bearing mice in vivo showed that Al 18F-FAP-NOX was highly uptaken in FAP-positive tumor tissues (60 min: (12.47±1.66) percentage activity of injection dose per gram of tissue (%ID/g)), while the uptake was very low in FAP-negative tumors. The biodistribution results were similar to the microPET/CT imaging results of tumor-bearing mice. The human clinical imaging showed an abnormal increase in Al 18F-FAP-NOX uptake (SUV max 5.5) of the lung cancer lesions. Conclusions:A novel cyclic peptide radiopharmaceutical, Al 18F-FAP-NOX, demonstrates good stability and hydrophilicity. It can be quickly distributed to tumor tissue in vivo. The human clinical PET/CT imaging shows certain diagnostic ability of Al 18F-FAP-NOX for lung cancer lesions. It is a promising cyclic peptide agent for PET imaging.

Objective:To systematically evaluate the safety and efficacy of the novel fibroblast activation protein (FAP)-targeted tracer 64Cu-FAP inhibitor (FAPI)-XT117 in patients with malignant solid tumors, and to compare with 18F-FDG. Methods:This self-controlled study was conducted on fifteen patients (8 males, 7 females; age (60 ±9) years) with malignant solid tumors from the First Affiliated Hospital of Guangzhou Medical University between July 2023 and December 2023. Each subject underwent 64Cu-FAPI-XT117 PET/CT at 30, 60, and 120min post-injection and was assigned to three dose cohorts (111MBq, 148MBq, and 185MBq; 5 patients in each cohort), and safety assessments were conducted within 24h after injection. In addition, all patients underwent 18F-FDG PET/CT at 60min post-injection. Time-activity curves were generated for 64Cu-FAPI-XT117, and the dosimetry was calculated. Image quality was evaluated using a 5-point Likert scale, and the optimal injected activity and imaging time point were determined. The paired t test was used to compare differences of the lesion detection count and SUV max between 64Cu-FAPI-XT117 and 18F-FDG PET/CT. Results:64Cu-FAPI-XT117 was well tolerated, with no adverse events reported. Time-activity curves of 68Ga-FAPI-XT117 revealed prominent uptake in the uterus, while the background activity in other organs remained low, with the whole-body effective dose of (0.0084±0.0021)mSv/MBq. The optimal imaging time point for 64Cu-FAPI-XT117 PET/CT was 60min post-injection, with an optimal administered activity of 111MBq. Compared with 18F-FDG, 64Cu-FAPI-XT117 demonstrated significantly higher uptake and more lesions in lymph-node metastases (SUV max: 8.6±3.8 vs 15.3±6.8, t=2.33, P=0.048; number of lesions: 8.3±5.4 vs 15.0±6.4; t=4.21, P=0.003) and distant metastases (SUV max: 11.8±3.7 vs 20.9±7.2, t=3.66, P=0.022; number of lesions: 7.0±3.2 vs 12.4±3.7, t=2.86, P=0.046). Conclusions:64Cu-FAPI-XT117 PET/CT is well tolerated in patients with solid tumors, with a controllable radiation risk. Moreover, it outperforms 18F-FDG PET/CT in the assessment of metastases.

OBJECTIVE: To develop an artificial intelligence-assisted system for the automatic detection of the features of common 21 auricular points based on the YOLOv8 neural network. METHODS: A total of 660 human auricular images from three research centers were collected from June 2019 to February 2024. The rectangle boxes and features of images were annotated using the LabelMe5.3.1 tool and converted them into a format compatible with the YOLO model. Using these data, transfer learning and fine-tuning training were conducted on different scales of pretrained YOLO neural network models. The model's performance was evaluated on validation and test sets, including the mean average precision (mAP) at various thresholds, recall rate (recall), frames per second (FPS) and confusion matrices. Finally, the model was deployed on a local computer, and the real-time detection of human auricular images was conducted using a camera. RESULTS: Five different versions of the YOLOv8 key-point detection model were developed, including YOLOv8n, YOLOv8s, YOLOv8m, YOLOv8l, and YOLOv8x. On the validation set, YOLOv8n showed the best performance in terms of speed (225.736 frames per second) and precision (0.998). On the external test set, YOLOv8n achieved the accuracy of 0.991, the sensitivity of 1.0, and the F1 score of 0.995. The localization performance of auricular point features showed the average accuracy of 0.990, the precision of 0.995, and the recall of 0.997 under 50% intersection ration (mAP⁵⁰). CONCLUSION The key-point detection model of 21 common auricular points based on YOLOv8n exhibits the excellent predictive performance, which is capable of rapidly and automatically locating and classifying auricular points.
Humans ; Neural Networks, Computer ; Artificial Intelligence ; Acupuncture Points

To evaluate the clinical application value of magnetic bead sorting technology (MBS) using the T-cell select kit combined with an automatic cell sorter for isolating peripheral blood mononuclear cells (PBMCs) to realize automated specimen pre-processing and process optimization in T-SPOT.TB assay. A cross-sectional study was conducted involving 300 patients recruited from the first affiliated hospital of Air Force Medical University from March 2023 to July 2024. Among them, there were 167 males and 133 females. The age range of the patients was 18 to 65 years, with a median age of 49.0 (33.3, 59.0) years and a mean age of (46.4±13.9) years. 4 ml of anticoagulated whole blood samples in duplicate were collected from each patient. One fresh sample (0-4 h) was processed immediately using density gradient centrifugation (DGC) for PBMC isolation, while the other was processed using MBS method at either 0-4 h or 34-54 h post-collection. The cycles for cell enrichment step of the automatic cell sorter were adjusted from the conventional 4 cycles to 2 cycles. Statistical analysis was performed using Cohen′s Kappa test to evaluate the concordance of T-SPOT.TB results across all processing groups. The results showed that for fresh samples (0-4 h), the T-SPOT.TB results for samples processed with 4-cycle and 2-cycle MBS enrichment steps demonstrated positive concordance rates of 91.7% and 93.1%, negative concordance rates of 100% for both, overall concordance rates of 98.0% and 97.9%, and Kappa values of 0.94 and 0.95, respectively, compared with the reference results for paired samples processed using DGC. Correspondingly, the results for samples processed with the 4-cycle and 2-cycle MBS methods at 34-54 h post-collection yielded positive concordance rates of 90.0% and 81.3%, negative concordance rates of 95.1% and 100%, overall concordance rates of 93.0% and 82.9%, and Kappa values of 0.86 and 0.43, respectively, compared with the reference results for fresh samples processed using DGC. In conclusion,for 0-4 h samples, the T-SPOT.TB results from both 4-cycle and 2-cycle MBS enrichment protocols were highly consistent with the reference results from conventional DGC methods. However, for 34-54 h stored samples, results from the 4-cycle MBS method rather than the 2-cycle protocol exhibited significantly superior concordance with the reference results. The MBS method using T-Cell Select kit achieves automated sample pre-processing for T-SPOT.TB assay, reduces hands-on time, and provides a viable alternative with reliable results for long-stored specimens.

Objective:To develop a novel fibroblast activation protein (FAP) cyclic peptide imaging agent, Al 18F-FAP-NOX, evaluate its in vitro and in vivo properties, and explore its feasibility of PET/CT imaging in tumors with FAP positive expression. Methods:Al 18F-FAP-NOX was manually synthesized. The in vitro stability of Al 18F-FAP-NOX was determined using radio high performance liquid chromatography (HPLC). The lipid water partition coefficient log P, in vitro cell uptake experiments, microPET/CT imaging and biodistribution in 293T-FAP tumor-bearing mice were conducted to preliminarily evaluate the pharmacokinetics and biological efficacy of Al 18F-FAP-NOX. Afterwards, a patient (male, 65 years old) with lung cancer underwent Al 18F-FAP-NOX PET/CT imaging. Results:Al 18F-FAP-NOX was successfully synthesized with a yield of (26.28±2.31)% without attenuation correction ( n=4), and the radiochemical purity was more than 95%. Al 18F-FAP-NOX exhibited good stability and hydrophilicity (log P=-3.02±0.08, n=5). In cell assays, the uptake of Al 18F-FAP-NOX in HT1080-FAP cells reached the plateau phase at 15 min ((7.31±0.53) percentage activity of injection dose per million cells (%ID/mio cells)), exhibiting high cellular uptake. The uptake of Al 18F-FAP-NOX could be significantly inhibited by 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)-FAP-2286. The microPET/CT results of 293T-FAP tumor-bearing mice in vivo showed that Al 18F-FAP-NOX was highly uptaken in FAP-positive tumor tissues (60 min: (12.47±1.66) percentage activity of injection dose per gram of tissue (%ID/g)), while the uptake was very low in FAP-negative tumors. The biodistribution results were similar to the microPET/CT imaging results of tumor-bearing mice. The human clinical imaging showed an abnormal increase in Al 18F-FAP-NOX uptake (SUV max 5.5) of the lung cancer lesions. Conclusions:A novel cyclic peptide radiopharmaceutical, Al 18F-FAP-NOX, demonstrates good stability and hydrophilicity. It can be quickly distributed to tumor tissue in vivo. The human clinical PET/CT imaging shows certain diagnostic ability of Al 18F-FAP-NOX for lung cancer lesions. It is a promising cyclic peptide agent for PET imaging.

Objective:To systematically evaluate the safety and efficacy of the novel fibroblast activation protein (FAP)-targeted tracer 64Cu-FAP inhibitor (FAPI)-XT117 in patients with malignant solid tumors, and to compare with 18F-FDG. Methods:This self-controlled study was conducted on fifteen patients (8 males, 7 females; age (60 ±9) years) with malignant solid tumors from the First Affiliated Hospital of Guangzhou Medical University between July 2023 and December 2023. Each subject underwent 64Cu-FAPI-XT117 PET/CT at 30, 60, and 120min post-injection and was assigned to three dose cohorts (111MBq, 148MBq, and 185MBq; 5 patients in each cohort), and safety assessments were conducted within 24h after injection. In addition, all patients underwent 18F-FDG PET/CT at 60min post-injection. Time-activity curves were generated for 64Cu-FAPI-XT117, and the dosimetry was calculated. Image quality was evaluated using a 5-point Likert scale, and the optimal injected activity and imaging time point were determined. The paired t test was used to compare differences of the lesion detection count and SUV max between 64Cu-FAPI-XT117 and 18F-FDG PET/CT. Results:64Cu-FAPI-XT117 was well tolerated, with no adverse events reported. Time-activity curves of 68Ga-FAPI-XT117 revealed prominent uptake in the uterus, while the background activity in other organs remained low, with the whole-body effective dose of (0.0084±0.0021)mSv/MBq. The optimal imaging time point for 64Cu-FAPI-XT117 PET/CT was 60min post-injection, with an optimal administered activity of 111MBq. Compared with 18F-FDG, 64Cu-FAPI-XT117 demonstrated significantly higher uptake and more lesions in lymph-node metastases (SUV max: 8.6±3.8 vs 15.3±6.8, t=2.33, P=0.048; number of lesions: 8.3±5.4 vs 15.0±6.4; t=4.21, P=0.003) and distant metastases (SUV max: 11.8±3.7 vs 20.9±7.2, t=3.66, P=0.022; number of lesions: 7.0±3.2 vs 12.4±3.7, t=2.86, P=0.046). Conclusions:64Cu-FAPI-XT117 PET/CT is well tolerated in patients with solid tumors, with a controllable radiation risk. Moreover, it outperforms 18F-FDG PET/CT in the assessment of metastases.