Comprehensive analysis of the UDP-glucuronate decarboxylase (UXS) gene family in tobacco and functional characterization of NtUXS16 in Golgi apparatus in Arabidopsis.

BACKGROUND: UDP-glucuronate decarboxylase (also named UXS) converts UDP-glucuronic acid (UDP-GlcA) to UDP-xylose (UDP-Xyl) by decarboxylation of the C6-carboxylic acid of glucuronic acid. UDP-Xyl is an important sugar donor that is required for the synthesis of plant cell wall polysaccharides. RESULTS: In this study, we first carried out the genome-wide identification of NtUXS genes in tobacco. A total of 17 NtUXS genes were identified, which could be divided into two groups (Group I and II), and the Group II UXSs can be further divided into two subgroups (Group IIa and IIb). Furthermore, the protein structures, intrachromosomal distributions and gene structures were thoroughly analyzed. To experimentally verify the subcellular localization of NtUXS16 protein, we transformed tobacco BY-2 cells with NtUXS16 fused to the monomeric red fluorescence protein (mRFP) at the C terminus under the control of the cauliflower mosaic virus (CaMV) 35S promoter. The fluorescent signals of NtUXS16-mRFP were localized to the medial-Golgi apparatus. Contrary to previous predictions, protease digestion analysis revealed that NtUXS16 is not a type II membrane protein. Overexpression of NtUXS16 in Arabidopsis seedling in darkness led to a significant increase in hypocotyl length and a reduction in root length compared with the wild type. In summary, these results suggest Golgi apparatus localized-NtUXS16 plays an important role in hypocotyl and root growth in the dark. CONCLUSION: Our findings facilitate our understanding of the novel functions of NtUXS16 and provide insights for further exploration of the biological roles of NtUXS genes in tobacco.

Biodistribution and Internal Dosimetry of 68 Ga-DOTA-IBA PET Imaging for Patients With Bone Metastases.

PURPOSE: We have developed a new pharmaceutical, ibandronic acid (IBA), and preliminarily demonstrated that it is an efficient bisphosphonate for the diagnosis and treatment of bone metastases. This study aims to examine the biodistribution and internal dosimetry of the diagnostic 68 Ga-DOTA-IBA in patients. PATIENTS AND METHODS: 68 Ga-DOTA-IBA was intravenously injected based on 1.81-2.57 MBq/Kg into 8 patients with bone metastases. Each patient underwent 4 sequential static whole-body PET scans at 0.1, 0.45, 0.8, and 1.8 hours after injection. The acquisition time for each scan was 20 minutes with 10 bed positions. Image registrations and volume of interest delineation were first performed on Hermes, whereas percentage injected activity (%IA), absorbed dose, and effective dose were measured for source organs, using OLINDA/EXM v2.0. Dosimetrics for the bladder was based on a bladder voiding model. RESULTS: No adverse effects were observed on all patients. After the injection, 68 Ga-DOTA-IBA rapidly accumulated in bone metastases and cleared from nonbone tissues, as indicated by visual analysis and %IA measured on the sequential scans. High activity uptake was presented in the expected target organs, that is, bone, red marrow, and the drug-excretion organs such as kidneys and bladder. The mean total body effective dose is 0.022 ± 0.002 mSv/MBq. CONCLUSIONS: 68 Ga-DOTA-IBA has high bone affinity and is promising in the diagnosis of bone metastases. Dosimetric results show that the absorbed doses for critical organs and total body are within the safety limit and with high bone retention. It also has the potential to be used in 177 Lu-therapy as a theranostic pair.

[Optimization of parameters for stir-frying of Kansui Radix with vinegar based on conversion of toxic components].

This study aims to optimize the parameters for stir-frying of Kansui Radix with vinegar based on the conversion of representative toxic diterpenes, which is expected to serve as a reference for the standardized production of Kansui Radix stir-fried with vinegar. To be specific, the toxic components [3-O-(2'E,4'Z-decadienoyl)-20-O-acetylingenol(3-O-EZ), kansuiphorin C(KPC)] in Kansui Radix and the products(ingenol, 20-deoxyingenol) after the stir-frying with vinegar were selected. The toxicity to intestine and water-draining activity were evaluated with NCM460(normal human colon mucosal epithelial cell line) and HT-29(a human colorectal adenocarcinoma cell line). An HPLC method was then developed to assess the conversion of toxic components. On this basis, temperature, time, and amount of vinegar for the processing of Kansui Radix were optimized with the Box-Behnken design and the content of ingenol and 20-deoxyingenol as evaluation index. The results showed that after the stir-frying of Kansui Radix with vinegar, 3-O-EZ and KPC were first converted to monoester 3-O-(2'E,4'Z-decadienoyl)ingenol(3-EZ) and 5-O-benzoyl-20-deoxyingenol(5-O-Ben) and finally to almost non-toxic ingenol and 20-deoxyingenol, respectively. Meanwhile, the water-draining activity was retained. Six compounds had a good linear relationship with the peak area in the corresponding concentration ranges(R~2≥0.999 8), and the average recovery fell in the range of 98.20%-102.3%(RSD≤2.4%). The content of representative diterpenes and intermediate products was 14.78%-24.67% lower in the Kansui Radix stir-fried with vinegar than in the Kansui Radix, while the content of the conversed products was 14.37%-71.37% higher. Among the process parameters, temperature had significant influence on the total content of products, followed by time. The optimal parameters were 210 ℃, 15 min, and 30% vinegar. The relative error between the experimental results and the predicted values was 1.68%, indicating that the process was stable and reproducible. The strategy of screening optimal parameters for stir-frying of Kansui Radix with vinegar based on the transformation of toxic components can help improve the production stability, reduce the toxicity, and ensure the efficacy of Kansui Radix stir-fried with vinegar, which can serve as a reference for the process optimization of similar toxic Chinese medicinals.

The Influence of Agricultural Work and Plasma Uric Acid on Hospital Admission for Alzheimer's Disease.

BACKGROUND: Exposure to environmental neurotoxins associated with agricultural work, such as pesticides, may be a risk factor for neurodegenerative disorders such as Alzheimer's (AD) and Parkinson's (PD) diseases. There is strong evidence that such exposure is associated with the development of PD; for AD the current evidence is equivocal. Several mechanisms are proposed to mediate this environmental toxicity, one of which is oxidative stress. Uric acid (UA) is an endogenous antioxidant, low levels of which are also implicated in neurodegenerative disease. OBJECTIVE: This study aimed to determine whether agricultural work was a risk factor for AD in a population in which its association with PD was established, and whether UA was also associated with AD in this cohort. METHODS: Hospital records of subjects meeting criteria for AD (n = 128) or vascular dementia (VaD) (n = 178) after hospital admission for symptoms of dementia were studied. History of agricultural work and plasma UA were recorded and their relationship to diagnosis determined. RESULTS: In contrast to previous findings in this population in which agricultural work was strongly associated with PD, a history of agricultural work was not over-represented in hospital admission for AD versus VaD. AD was associated with a reduced level of circulating UA compared with VaD. CONCLUSION: Agricultural work as a likely proxy for exposure to pesticides appears not to be a risk factor for AD to the extent found in PD, perhaps reflecting their differences in neuronal pathology. Nevertheless, findings with UA suggests that oxidative stress may be an important factor in AD pathogenesis.

Safety and Efficacy of 68 Ga- or 177 Lu-Labeled DOTA-IBA as a Novel Theranostic Radiopharmaceutical for Bone Metastases : A Phase 0/I Study.

PURPOSE: We designed and synthesized a novel theranostic bisphosphonate radiopharmaceutical ( 68 Ga- or 177 Lu-labeled DOTA-ibandronic acid [ 68 Ga/ 177 Lu-DOTA-IBA]) for bone metastasis. In this study, the dosimetry, safety, and efficacy of 68 Ga/ 177 Lu-DOTA-IBA as a theranostic radiopharmaceutical for bone metastases were evaluated in patients with malignancy based on 68 Ga- and 177 Lu-DOTA-IBA images, blood samples, and dosimetric analysis. PATIENTS AND METHODS: Eighteen patients with bone metastasis and progression under conventional therapies were included in this study. Baseline 99m Tc-MDP SPECT and 68 Ga-DOTA-IBA PET/CT were performed for comparative purposes within 3 days. After receiving 891.5 ± 301.3 MBq 177 Lu-DOTA-IBA, serial 177 Lu-DOTA-IBA SPECT bone scan was performed over 14 days. Dosimetric evaluation was performed for main organs and tumor lesions. Safety was assessed by blood biomarkers. Karnofsky Performance Status, pain score, and follow-up 68 Ga-DOTA-IBA PET/CT were performed for response evaluation. RESULTS: Baseline 68 Ga-DOTA-IBA PET demonstrated a higher efficacy for detecting bone metastases compared with 99m Tc-MDP SPECT. The time-activity curves showed fast uptake and high retention of 177 Lu-DOTA-IBA in bone metastases (24 hours: 9.43 ± 2.75 %IA; 14 days: 5.45 ± 2.52 %IA). Liver, kidneys, and red marrow time-activity curves revealed a low uptake and fast clearance. The radiation-absorbed dose in bone metastasis lesions (6.40 ± 2.13 Gy/GBq) was significantly higher than that in red marrow (0.47 ± 0.19 Gy/GBq), kidneys (0.56 ± 0.19 Gy/GBq), or liver (0.28 ± 0.07 Gy/GBq), with all P 's < 0.001. Compared with baseline level, only one patient developed new grade 1 leukopenia (toxicity rate, 6%). The 177 Lu-DOTA-IBA therapy had no statistically significant effect on bone marrow hematopoietic function, liver function, and kidney function at any follow-up visit. Bone pain palliation was achieved in 82% (14/17) of patients. The 8-week follow-up 68 Ga-DOTA-IBA PET/CT demonstrated partial response in 3 patients, disease progression in 1 patient, and stable disease in 14 patients. CONCLUSIONS: 68 Ga/ 177 Lu-DOTA-IBA provides a set of potential theranostic radiopharmaceuticals and may have a good prospect for the management of bone metastasis.

Lutetium177-Labeled DOTA-Ibandronate: A Novel Radiopharmaceutical for Targeted Treatment of Bone Metastases.

Bone metastases of malignant tumors significantly threaten the patient survival and quality of life. We designed and synthesized a novel bisphosphonate radiopharmaceutical [68Ga- or 177Lu-labeled DOTA-Ibandronate(68Ga/177Lu-DOTA-IBA)] for targeted diagnosis and treatment of bone metastases. This study explored the basic biological characteristics of 177Lu-DOTA-IBA, guiding clinical translation and providing evidence for future clinical applications. The control variable method was used to optimize the optimal labeling conditions. The in vitro properties, biological distribution, and toxicity of 177Lu-DOTA-IBA were studied. Normal mice and tumor-bearing mice were imaged using micro SPECT/CT. With Ethics Committee approval, five volunteers were recruited for a preliminary clinical translation study. 177Lu-DOTA-IBA has a radiochemical purity of more than 98%, with good biological properties and safety. Blood clearance is fast and soft tissue uptake is low. Tracers are excreted mainly through the urinary system, targeting and continuously concentrating in the bones. Three patients experienced significant pain relief within 3 days after 177Lu-DOTA-IBA treatment (740-1110 MBq), lasting more than 2 months, with no toxic side effects. 177Lu-DOTA-IBA is easy to prepare and exhibits good pharmacokinetic characteristics. Low-dose 177Lu-DOTA-IBA is effective, well tolerated, and was associated with no significant adverse reactions. It is a promising radiopharmaceutical for the targeted treatment of bone metastases, controlling the progress of bone metastasis and improving survival and quality of life of patients with advanced bone metastasis.

Total variation regularized expectation maximization reconstruction improves 68Ga-FAPI-04 PET/CT image quality as compared to ordered subset expectation maximization reconstruction.

BACKGROUND: This study aimed to investigate improvements in 68Ga-FAPI PET/CT image quality due to using total variation regularized expectation maximization (TVR-EM) and ordered subset expectation maximization (OS-EM) reconstruction. METHODS: Data from a total of 24 patients were retrospectively analyzed in this study. Positron emission tomography (PET) images were reconstructed using OS-EM and TVR-EM for 2 and 3 minutes-per-bed (min/bed) acquisition. The SUVmean of a region-of-interest on the liver, image noise, signal-to-noise ratios (SNR), the SUVmax of the lesions and the tumour-to-background ratios (TBR) were measured and compared between the 2 methods. Subjective image qualities were evaluated by two experienced radiologists using a 5-point score scale (5-excellent, 1-poor). RESULTS: In total, 132 lesions were analyzed. The image noise in TVR-EM reconstruction groups was lower than in the OS-EM groups (all P<0.05). The SNR, SUVmax of lesions and the TBR were higher for the TVR-EM reconstruction groups compared to OS-EM groups (all P<0.05). Also, the SUVmax of the lesions in the TVR-EM groups increased by at least 12% compared to OS-EM 3 min/bed group. The SUVmax for small (<10 mm) and large lesions (>10 mm) in the TVR-EM 2 min/bed group were significantly larger compared to the OS-EM 3 min/bed groups (all P<0.05). The highest image quality score resulted from the TVR-EM 3 min/bed group with a penalization factor of 0.25 (3.92±0.19). CONCLUSIONS: TVR-EM reduces image noise and improved the SNR, SUVmax and TBR of the lesions. It also enables fast acquisition without compromising image quality compared to standard OS-EM.

The Impact of Total Variation Regularized Expectation Maximization Reconstruction on 68Ga-DOTA-TATE PET/CT Images in Patients With Neuroendocrine Tumor.

Objective: The aim of this study was to investigate the effects of the total variation regularized expectation maximization (TVREM) reconstruction on improving 68Ga-DOTA-TATE PET/CT images compared to the ordered subset expectation maximization (OSEM) reconstruction. Method: A total of 17 patients with neuroendocrine tumors who underwent clinical 68Ga-DOTA-TATE PET/CT were involved in this study retrospectively. The PET images were acquired with either 3 min-per-bed (min/bed) acquisition time and reconstructed with OSEM (2 iterations, 20 subsets, and a 3.2-mm Gaussian filter) and TVREM (seven penalization factors = 0.01, 0.07, 0.14, 0.21, 0.28, 0.35, and 0.42) for 2 and 3 min-per-bed (min/bed) acquisition time using list-mode. The SUVmean of the liver, background variability (BV), signal-to-noise ratios (SNR), SUVmax of the lesions and tumor-to-background ratios (TBR) were measured. The mean percentage difference in the SNR and TBR between TVREM with difference penalization factors and OSEM was calculated. Qualitative image quality was evaluated by two experienced radiologists using a 5-point score scale (5-excellent, 1-poor). Results: In total, 63 lesions were analyzed in this study. The SUVmean of the liver did not differ significantly between TVREM and OSEM. The BV of all TVREM groups was lower than OSEM groups (all p < 0.05), and the BV of TVREM 2 min/bed group with penalization factor of 0.21 was considered comparable to OSEM 3 min/bed group (p = 0.010 and 0.006). The SNR, SUVmax and TBR were higher for all TVREM groups compared to OSEM groups (all p < 0.05). The mean percentage difference in the SNR and TBR was larger for small lesions (<10 mm) than that for medium (≥10 mm but < 20 mm) and large lesions (≥20 mm). The highest image quality score was given to TVREM 2 min/bed group with penalization factor of 0.21 (3.77 ± 0.26) and TVREM 3 min/bed group with penalization factor of 0.35 (3.77 ± 0.26). Conclusion: TVREM could reduce image noise, improve the SNR, SUVmax and TBR of the lesions, and has the potential to preserves the image quality with shorter acquisition time.

Preparation, Characterization, and Preliminary Imaging Study of [188Re]Re-Ibandronate as a Novel Theranostic Radiopharmaceutical for Bone Metastasis.

Background: Bone is a common site of metastasis from a malignant tumor. Several radiopharmaceuticals are available to relieve bone pain in patients with cancer. However, every radiopharmaceutical has its own disadvantages, and there is still a need to investigate easily accessible and high bone affinity radiopharmaceuticals. Ibandronate (IBA) and 188Re were used for radiolabeling to develop and evaluate a novel type of bone-seeking radiopharmaceutical. Methods: The preparation conditions of [188Re]Re-IBA were investigated, and thin-layer chromatography was used to analyze radiochemical purity. The stability, plasma protein binding rate, lipid-water distribution coefficient, safety and biodistribution in normal mice, and bone imaging of [188Re]Re-IBA in New Zealand rabbits were studied. In addition, the nude mice model of bone metastasis was established, and biodistribution and imaging characteristics of [188Re]Re-IBA in these nude mice were studied. Results: [188Re]Re-IBA was successfully prepared with radiochemical purity >95%. The optimum preparation conditions were as follows: IBA, 0.8-1.4 mg; ascorbic acid, 0.2-0.5 mg; stannous chloride, 0.14-0.18 mg; potassium perrhenate, 0.005 mg; and [188Re]ReO4 - activity, 18.5-296 MBq, reacted for 30 min at 95°C with pH = 2. [188Re]Re-IBA demonstrated good stability, high plasma protein binding rate, good hydrophilicity, and low toxicity. The biodistribution and bone imaging in normal animals showed rapid blood clearance, high bone uptake, low uptake in the solid organs and soft tissue, and high contrast during imaging. The biodistribution and imaging of bone metastasis in nude mice showed that [188Re]Re-IBA has higher uptake in bone metastasis lesions than normal bone. Conclusions: Our study encompassed the successful preparation of [188Re]Re-IBA, a novel bone-seeking radiopharmaceutical, and confirmed it has potential in the treatment of bone metastasis and monitoring through imaging.

Preparation, biological characterization and preliminary human imaging studies of 68Ga-DOTA-IBA.

Purpose: In this study, DOTA-IBA was radiolabeled with 68Ga and we determined the optimum labelling conditions and assessed the biological properties of 68Ga-DOTA-IBA. We investigated the biodistribution of 68Ga-DOTA-IBA in normal animals and undertook PET/CT imaging in humans. Finally, we explored the feasibility 68Ga-DOTA-IBA as a bone imaging agent and demonstrated its potential for the therapeutic release of 177Lu/225Ac-DOTA-IBA. Methods: The controlled variables method was used to assess the impact of variables on the radiochemical purity of 68Ga-DOTA-IBA. The biological properties of 68Ga-DOTA-IBA were investigated.68Ga-DOTA-IBA micro-PET/CT imaging was performed on animals. Volunteers were recruited for 68Ga-DOTA-IBA imaging and data were compared to 99mTc-MDP imaging studies to calculate the target to non-target ratio (T/NT) of the lesions. Results: The prepared 68Ga-DOTA-IBA had a radiochemical purity of >97% and demonstrated good biological properties with a good safety profile in normal mice. PET/CT imaging of the animals showed rapid blood clearance with high contrast between the bone and stroma. Human imaging showed that 68Ga-DOTA-IBA could detect more lesions compared to 99mTc-MDP and had a higher targeted to untargeted ratio. Conclusions: 68Ga-DOTA-IBA is an osteophilic radiopharmaceutical that can be synthesized using a simple labelling method. 68Ga-DOTA-IBA has high radiochemical purity and is stable in vitro stability. It is rapidly cleared from the blood, has low toxicity and has strong targeting to the bone with long retention times. We also found that it is rapidly cleared in non-target tissues and has high contrast on whole-body bone imaging. 68Ga-DOTA-IBA PET/CT has potential as a novel bone imaging bone modality in patients with metastatic disease.

The potential utility of [68 Ga]Ga-DOTA-FAPI-04 as a novel broad-spectrum oncological and non-oncological imaging agent-comparison with [18F]FDG.

PURPOSE: This study aimed to compare the detection performance of [68 Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/CT in the patients with various oncological and non-oncological lesions. METHODS: A total of 123 patients underwent contemporaneous [68 Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/CT were included in this prospective study. The maximum standard uptake value (SUVmax) was measured to compare oncological and non-oncological lesion uptake. The sensitivity, specificity, predictive values, and accuracy of [18F]FDG and [68 Ga]Ga-DOTA-FAPI-04 PET/CT for detecting primary, metastatic, and non-oncological lesions were calculated and compared to evaluate the detection efficacy. RESULTS: The study subjects consisted of 123 patients (69 men and 54 women; mean age 56.11 ± 11.94 years). Among the 102 patients with either newly diagnosed (82 patients) or previously treated solid tumor (20 patients), a total of 88 solid primary malignant tumors in 84/102 patients were detected. Two patients had two primary tumors each and 1 patient had three primary tumors. Among them, 58/102 and 43/102 patients had nodal (376 lesions) and distant metastases (406 lesions), respectively. Eight patients had hematological neoplasm. No malignant oncological diseases were detected in the remaining 13 patients. A total of 145 non-oncological lesions and benign tumors in 52/123 patients were detected incidentally. [68 Ga]Ga-DOTA-FAPI-04 PET/CT demonstrated a significantly higher uptake and detection rate for the primary (SUVmax 10.98 ± 5.83 vs. 8.36 ± 6.43, p < 0.001; sensitivity 97.67 vs. 84.89%; and accuracy 96.59 vs. 82.95%, X2 = 0.538, p = 0.021), nodal (SUVmax 10.50 ± 5.98 vs. 8.20 ± 6.29, p = 0.011; sensitivity 97.59 vs. 84.72%; and accuracy 97.34 vs. 84.31%, X2 = 2.067, p < 0.001), and distant metastatic lesions (SUVmax 9.64 ± 6.45 vs. 6.74 ± 4.83; p < 0.001; sensitivity 98.01 vs. 65.59%; and accuracy 97.04 vs. 65.51%, X2 = 4.897, p < 0.001) of solid tumor than did [18F]FDG PET/CT. [68 Ga]Ga-DOTA-FAPI-04 PET/CT demonstrated a lower activity (SUVmax: 6.84 ± 4.67 vs. 13.09 ± 7.29, p < 0.001) and detection rate (sensitivity 50.65 vs. 96.75%, and accuracy 51.28 vs. 95.51%, X2 = 5.166, p < 0.001) for multiple myeloma and lymphoma compared to [18F]FDG PET/CT. [68 Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/CT PET/CT demonstrated a comparative activity (SUVmax 6.40 ± 3.95 vs. 5.74 ± 15.78, p = 0.729) and detection efficacy (sensitivity 86.52 vs. 72.34%, and accuracy 84.83 vs. 72.41%, X2 = 9.460, p = 0.007) for non-oncological lesion and benign tumor detection. CONCLUSIONS: Except for myeloma and lymphoma, [68 Ga]Ga-DOTA-FAPI-04 PET/CT showed a superior detection efficacy for detecting various primary and metastatic lesions than [18F]FDG PET/CT. A comparative detection utility for non-oncological lesion was obtained with both tracers. [68 Ga]Ga-DOTA-FAPI-04 could be used as a broad-spectrum tumor and inflammatory imaging agent in the clinical especially for various solid tumors and non-oncological lesions.

FAPI PET/CT research progress in digestive system tumours.

18F-fluorodeoxyglucose positron emission tomography/computed tomography has been used in clinical practice for many years. This modality is of great value for tumour diagnosis, staging, and efficacy evaluations, but it has many limitations in the diagnosis and treatment of digestive system tumours. Fibroblast activation protein is highly expressed in gastrointestinal tumours. Various isotope-labelled fibroblast activation protein inhibitors are widely used in clinical research. These inhibitors have low background uptake in the brain, liver and oral/pharyngeal mucosa and show good contrast between the tumour and background, which makes up for the lack of fluorodeoxyglucose in the diagnosis of digestive system tumours. It better displays the primary tumours, metastases and regional lymph nodes of digestive system tumours, such as oesophageal cancer, gastric cancer and liver cancer, and also provides a new method for treating these tumours. Based on this background, this article introduces the current research status of fibroblast activation protein inhibitor positron emission tomography/computed tomography in various types of digestive system malignant tumours to provide more valuable information for diagnosing and treating digestive system tumours.

68Ga-FAPI PET/CT Detected Non-FDG-Avid Gastric Stromal Tumor.

ABSTRACT: We presented a case of 67-year-old man with epigastric discomfort and anorexia for more than 2 months. No abnormal 18F-FDG uptake was found throughout the gastrointestinal tract on 18F-FDG PET/CT. The patient was enrolled in the 68Ga-FAPI PET/CT clinical trial, and a 68Ga-FAPI PET/CT was performed to help detect primary lesion. This examination demonstrated a nodular thickening of the gastric wall with an increased 68Ga-FAPI uptake in the greater curvature of the stomach. Finally, the pathological result confirmed the diagnosis of gastric stromal tumor. This case highlights that 68Ga-FAPI PET/CT might outperform 18F-FDG PET/CT in helping identify gastrointestinal stromal tumors.

A Novel Small Cyclic Peptide-Based 68Ga-Radiotracer for Positron Emission Tomography Imaging of PD-L1 Expression in Tumors.

In the tumor microenvironment, programmed death protein 1 and programmed death protein ligand 1 (PD-L1) signaling pathways help tumors escape the immune system. We designed a gallium-68 (68Ga)-labeled small-molecule peptide-targeting PD-L1 and used positron emission tomography/computed tomography (PET/CT) to detect and dynamically monitor the expression level of PD-L1 in tumors. S-Cyclo(ETSK)-SF-NH2 (SETSKSF) is a cyclic peptide inhibitor comprising seven amino-acid residues. We connected it with the chelating agent DOTA, labeled DOTA-SETSKSF, with the short half-life nuclide Ga-68, and measured the stability of 68Ga-2,2',2″-(10-(2-((S)-1-((3S,6S,9S,18S)-18-((S)-1-((S)-1-amino-1-oxo-3-henylpropan-2-ylamino)-3-hydroxy-1-oxopropan-2-ylcarbamoyl)-6-((R)-1-hydroxyethyl)-3-(hydroxymethyl)-2,5,8,12-tetraoxo-1,4,7,13-tetraazacyclooctadecan-9-ylamino)-3-ydroxy-1-oxopropan-2-ylamino)-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid (68Ga-DOTA-SETSKSF) in normal saline (NS), phosphate-buffered saline (PBS), and fetal bovine serum (FBS) in vitro. We conducted the 68Ga-DOTA-SETSKSF affinity test, cell-specific uptake experiments, time-combined experiments, western blotting, and laser confocal experiments to confirm the expression and localization of PD-L1 at the cell level and determine the uptake. Biodistribution and imaging experiments were performed using the H1975, B16F10, and A549 tumor models. 68Ga-DOTA-SETSKSF was successfully synthesized, and the radiochemical purity was >99% after purification. The in vitro stability of 68Ga-DOTA-SETSKSF was >95% in NS, PBS, and FBS at 37 °C after 4 h of incubation. Cell-binding experiments confirmed that 68Ga-DOTA-SETSKSF exhibited high uptake in H1975 tumors with high PD-L1 expression and low uptake in A549 tumors with low PD-L1 expression. The clear half-life (T1/2) of 68Ga-DOTA-SETSKSF from the blood was 14.48 ± 3.26 min. The percentages of the injected dose per gram of tissue (%ID/g) for H1975 and A549 tumors were 5.29 ± 0.21 and 0.89 ± 0.10 at 1 h after injection, respectively. The H1975 tumor-to-muscle and tumor-to-blood ratios were 41.79 ± 5.81 and 4.75 ± 0.19 at 4 h, respectively. Apart from the H1975 tumor, the kidney and the bladder showed high accumulation because 68Ga-DOTA-SETSKSF was excreted through the urinary system. PET/CT images showed high accumulation of 68Ga-DOTA-SETSKSF in H1975 tumors and low uptake in A549 tumors, which was consistent with the results of biodistribution experiments. 68Ga-DOTA-SETSKSF is convenient to prepare, has high stability, can be used to monitor the expression of PD-L1, and has an extremely high clinical application value.

Distribution of phosphorus forms in surface soils of typical peatlands in northern Great Khingan Mountains and its potential to reconstruct paleo-vegetations.

Phosphorus was one of the nutrient limitations to vegetations in wetland ecosystem. In peatland, organic phosphorus is accumulated as vegetation residues in anaerobic conditions, affecting the contents of phosphorus pools for long time. It is unclear that different vegetations affect the contents of phosphorus and whether successions of vegetations could reflected by sedimentation of phosphorus forms. Phosphorus forms from six surface soils plots and four dominant vegetations in the north of the Great Khingan mountains were detected to investigate the differences of phosphorus forms of soil between different vegetations. Phosphorus forms and macrofossil were also detected in a 77-cm peat core (1-cm intervals) in TQ. A fingerprinting historical vegetations were reconstructed by phosphors forms to reflect successions of vegetations during 2200 cal yr BP in TQ area. The results showed that the main phosphorus forms in peatland were NaOH-Po and conc. HCl-Po. The percentages of inorganic phosphorus forms of trees were generally higher than other vegetations. Moss was more conducive for accumulation of organic phosphorus. NaHCO3-Pi, NaOH-Pi, conc. HCl-Po and Pi were selected into linear discrimination analysis. The vegetations reconstructed by phosphorus forms were strongly correlated with the pollen records of moss, herbs and shrubs, as well as with macrofossils in herbs. The fingerprinting of vegetations by phosphorus has potential geochemical reference to reflect the successions of vegetation in peatland.

Efficacy and tolerability of oral gastrodin for medication overuse headache (EASTERN): Study protocol for a multicenter randomized double-blind placebo-controlled trial.

Background: Prophylactic medication in clinical detoxification programs for the treatment of medication overuse headache is still debated. Gastrodin, a main bioactive constituent of Rhizoma Gastrodiae, has been applied clinically to treat primary headache for more than 30 years in China due to its potential analgesic and anti-migraine mechanisms. However, clinical evidence supporting its routing use in MOH is insufficient. The present study aims to investigate the efficacy and tolerability of oral gastrodin in medication overuse headache. Methods: A multicenter, randomized, double-blind, parallel, placebo-controlled trial will be performed. A target sample size of 186 patients who fulfill the International Classification of Headache Disorders 3rd version (ICHD-3) criteria for MOH will be recruited and screened during a baseline screening period of 28 days before being randomly assigned to either the gastrodin or placebo group at a ratio of 1:1. Enrolled patients will be assessed for each 4 weeks during the 12-weeks double-blind phase and followed up at week 24. The primary endpoint is mean change in monthly headache day frequency. Secondary endpoints will be the proportion of remitted MOH, change in headache pain intensity, headache impact test (HIT-6) score, 50% responder rate, treatment failure, monthly acute medication intake days, and Short Form 36-Item Health Survey (SF-36) score. Tolerability will be assessed by drop-out rates though safety monitoring during treatment. Discussion: The findings of the present study may help to provide new evidence on gastrodin as a prophylaxis treatment with both efficacy and high tolerability for the treatment of MOH. Clinical trail registration: Chinese Clinical Trail Registry (ChiCTR2200063719), Protocol Version 1.1, May, 09, 2022.

Identification of Mast Cell-Based Molecular Subtypes and a Predictive Signature in Clear Cell Renal Cell Carcinoma.

Background: Kidney renal clear cell carcinoma (KIRC) is a common malignant tumor of the urinary system. Surgery is the preferred treatment option; however, the rate of distant metastasis is high. Mast cells in the tumor microenvironment promote or inhibit tumorigenesis depending on the cancer type; however, their role in KIRC is not well-established. Here, we used a bioinformatics approach to evaluate the roles of mast cells in KIRC. Methods: To quantify mast cell abundance based on gene sets, a single-sample gene set enrichment analysis (ssGSEA) was utilized to analyze three datasets. Weighted correlation network analysis (WGCNA) was used to identify the genes most closely related to mast cells. To identify new molecular subtypes, the nonnegative matrix factorization algorithm was used. GSEA and least absolute shrinkage and selection operator (LASSO) Cox regression were used to identify genes with high prognostic value. A multivariate Cox regression analysis was performed to establish a prognostic model based on mast cell-related genes. Promoter methylation levels of mast cell-related genes and relationships between gene expression and survival were evaluated using the UALCAN and GEPIA databases. Results: A prolonged survival in KIRC was associated with a high mast cell abundance. KIRC was divided into two molecular subtypes (cluster 1 and cluster 2) based on mast cell-related genes. Genes in Cluster 1 were enriched for various functions related to cancer development, such as the TGFß signaling pathway, renal cell carcinoma, and mTOR signaling pathway. Based on drug sensitivity predictions, sensitivity to doxorubicin was higher for cluster 2 than for cluster 1. By a multivariate Cox analysis, we established a clinical prognostic model based on eight mast cell-related genes. Conclusion: We identified eight mast cell-related genes and constructed a clinical prognostic model. These results improve our understanding of the roles of mast cells in KIRC and may contribute to personalized medicine.

Identification of Nephrogenic Therapeutic Biomarkers of Wilms Tumor Using Machine Learning.

Wilms tumor is the most common renal malignancy in children, with a survival rate of more than 90%; however, treatment outcomes for certain patient subgroups, such as those with bilateral and recurrent diseases, remain significantly below this survival rate. Therefore, it remains essential to identify new biomarkers and develop effective therapeutic strategies. Based on the Therapeutically Applicable Research to Generate Effective Treatments and Gene Expression Omnibus RNA microarray datasets, we have identified eight differentially expressed genes in Wilms tumors as renal-specific in 33 randomly selected adult tumors. The risk model, constructed using survival forest and multivariate Cox regression, can effectively predict the prognosis; the risk score is an independent prognostic factor in Wilms tumor. Gene set enrichment analysis showed that most of the signature genes were involved in regulating human development-related pathways. At the same time, patients in the high-risk group exhibited more sensitive immunological and chemotherapeutic properties than those in the low-risk group. These results provide new insights into personalized and precise Wilms tumor treatment strategies.

Dynamic acceleration response of a rock slope with a horizontal weak interlayer in shaking table tests.

The weak interlayer in a rock slope often plays a significant role in seismic rockslides; however, the effect of weak interlayer on the seismic slope response and damage process is still not fully understood. This study presents a series of shaking test tests on two model slopes containing a horizontal weak interlayer with different thicknesses. A recorded Wenchuan earthquake ground motion was scaled to excite the slopes. Measurements from accelerometers embedded at different elevations of slope surface and slope interior were analyzed and compared. The effect of the weak interlayer thickness on the seismic response was highlighted by a comparative analysis of the two slopes in terms of topographic amplification, peak accelerations, and deformation characteristics as the input amplitude increased. It was found that the structure deterioration and nonlinear response of the slopes were manifested as a time lag of the horizontal accelerations in the upper slope relative to the lower slope and a reduction of resonant frequency and Fourier spectral ratio. Test results show that under horizontal acceleration, both slopes exhibited significant topographic amplification in the upper half, and the difference in amplification between slope face and slope interior was more pronounced in Slope B (with a thin weak interlayer) than in Slope A (with a thick weak interlayer). A four-phased dynamic response process of both slopes was observed. Similar deformation characteristics including development of strong response zone and macro-cracks, vertical settlement, horizontal extrusion and collapse in the upper half were observed in both slopes as the input amplitude increased; however, the deformations were more severe in Slope B than in Slope A, suggesting an energy isolation effect of the thick interlayer in Slope A.