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1.
Cell ; 186(17): 3726-3743.e24, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37442136

ABSTRACT

Elucidating the cellular organization of the cerebral cortex is critical for understanding brain structure and function. Using large-scale single-nucleus RNA sequencing and spatial transcriptomic analysis of 143 macaque cortical regions, we obtained a comprehensive atlas of 264 transcriptome-defined cortical cell types and mapped their spatial distribution across the entire cortex. We characterized the cortical layer and region preferences of glutamatergic, GABAergic, and non-neuronal cell types, as well as regional differences in cell-type composition and neighborhood complexity. Notably, we discovered a relationship between the regional distribution of various cell types and the region's hierarchical level in the visual and somatosensory systems. Cross-species comparison of transcriptomic data from human, macaque, and mouse cortices further revealed primate-specific cell types that are enriched in layer 4, with their marker genes expressed in a region-dependent manner. Our data provide a cellular and molecular basis for understanding the evolution, development, aging, and pathogenesis of the primate brain.


Subject(s)
Cerebral Cortex , Macaca , Single-Cell Analysis , Transcriptome , Animals , Humans , Mice , Cerebral Cortex/cytology , Cerebral Cortex/metabolism , Macaca/metabolism , Transcriptome/genetics
2.
Nature ; 624(7992): 672-681, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37935376

ABSTRACT

Trace-amine-associated receptors (TAARs), a group of biogenic amine receptors, have essential roles in neurological and metabolic homeostasis1. They recognize diverse endogenous trace amines and subsequently activate a range of G-protein-subtype signalling pathways2,3. Notably, TAAR1 has emerged as a promising therapeutic target for treating psychiatric disorders4,5. However, the molecular mechanisms underlying its ability to recognize different ligands remain largely unclear. Here we present nine cryo-electron microscopy structures, with eight showing human and mouse TAAR1 in a complex with an array of ligands, including the endogenous 3-iodothyronamine, two antipsychotic agents, the psychoactive drug amphetamine and two identified catecholamine agonists, and one showing 5-HT1AR in a complex with an antipsychotic agent. These structures reveal a rigid consensus binding motif in TAAR1 that binds to endogenous trace amine stimuli and two extended binding pockets that accommodate diverse chemotypes. Combined with mutational analysis, functional assays and molecular dynamic simulations, we elucidate the structural basis of drug polypharmacology and identify the species-specific differences between human and mouse TAAR1. Our study provides insights into the mechanism of ligand recognition and G-protein selectivity by TAAR1, which may help in the discovery of ligands or therapeutic strategies for neurological and metabolic disorders.


Subject(s)
GTP-Binding Proteins , Receptors, G-Protein-Coupled , Animals , Humans , Mice , Amines/metabolism , Amphetamine/metabolism , Antipsychotic Agents/chemistry , Antipsychotic Agents/metabolism , Binding Sites , Catecholamines/agonists , Catecholamines/chemistry , Catecholamines/metabolism , Cryoelectron Microscopy , GTP-Binding Proteins/chemistry , GTP-Binding Proteins/metabolism , GTP-Binding Proteins/ultrastructure , Ligands , Molecular Dynamics Simulation , Mutation , Polypharmacology , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/ultrastructure , Species Specificity , Substrate Specificity
3.
Proc Natl Acad Sci U S A ; 121(24): e2321532121, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38830102

ABSTRACT

Cannabis sativa is known for its therapeutic benefit in various diseases including pain relief by targeting cannabinoid receptors. The primary component of cannabis, Δ9-tetrahydrocannabinol (THC), and other agonists engage the orthosteric site of CB1, activating both Gi and ß-arrestin signaling pathways. The activation of diverse pathways could result in on-target side effects and cannabis addiction, which may hinder therapeutic potential. A significant challenge in pharmacology is the design of a ligand that can modulate specific signaling of CB1. By leveraging insights from the structure-function selectivity relationship (SFSR), we have identified Gi signaling-biased agonist-allosteric modulators (ago-BAMs). Further, two cryoelectron microscopy (cryo-EM) structures reveal the binding mode of ago-BAM at the extrahelical allosteric site of CB1. Combining mutagenesis and pharmacological studies, we elucidated the detailed mechanism of ago-BAM-mediated biased signaling. Notably, ago-BAM CB-05 demonstrated analgesic efficacy with fewer side effects, minimal drug toxicity and no cannabis addiction in mouse pain models. In summary, our finding not only suggests that ago-BAMs of CB1 provide a potential nonopioid strategy for pain management but also sheds light on BAM identification for GPCRs.


Subject(s)
Cryoelectron Microscopy , Receptor, Cannabinoid, CB1 , Signal Transduction , Receptor, Cannabinoid, CB1/metabolism , Receptor, Cannabinoid, CB1/genetics , Receptor, Cannabinoid, CB1/chemistry , Animals , Allosteric Regulation/drug effects , Mice , Humans , Signal Transduction/drug effects , GTP-Binding Proteins/metabolism , GTP-Binding Proteins/genetics , HEK293 Cells , Structure-Activity Relationship , Dronabinol/pharmacology , Dronabinol/chemistry , Dronabinol/analogs & derivatives , Cannabis/chemistry , Cannabis/metabolism
4.
Proc Natl Acad Sci U S A ; 121(30): e2401091121, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39024109

ABSTRACT

Achieving ligand subtype selectivity within highly homologous subtypes of G-protein-coupled receptor (GPCR) is critical yet challenging for GPCR drug discovery, primarily due to the unclear mechanism underlying ligand subtype selectivity, which hampers the rational design of subtype-selective ligands. Herein, we disclose an unusual molecular mechanism of entropy-driven ligand recognition in cannabinoid (CB) receptor subtypes, revealed through atomic-level molecular dynamics simulations, cryoelectron microscopy structure, and mutagenesis experiments. This mechanism is attributed to the distinct conformational dynamics of the receptor's orthosteric pocket, leading to variations in ligand binding entropy and consequently, differential binding affinities, which culminate in specific ligand recognition. We experimentally validated this mechanism and leveraged it to design ligands with enhanced or ablated subtype selectivity. One such ligand demonstrated favorable pharmacokinetic properties and significant efficacy in rodent inflammatory analgesic models. More importantly, it is precisely due to the high subtype selectivity obtained based on this mechanism that this ligand does not show addictive properties in animal models. Our findings elucidate the unconventional role of entropy in CB receptor subtype selectivity and suggest a strategy for rational design of ligands to achieve entropy-driven subtype selectivity for many pharmaceutically important GPCRs.


Subject(s)
Entropy , Molecular Dynamics Simulation , Receptors, G-Protein-Coupled , Ligands , Animals , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/chemistry , Humans , Protein Binding , Mice , Cryoelectron Microscopy , Receptors, Cannabinoid/metabolism , Receptors, Cannabinoid/chemistry , Binding Sites
5.
Mol Ther ; 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38273655

ABSTRACT

The last decade has seen rapid development in the field of cellular immunotherapy, particularly in regard to chimeric antigen receptor (CAR)-modified T cells. However, challenges, such as severe treatment-related toxicities and inconsistent quality of autologous products, have hindered the broader use of CAR-T cell therapy, highlighting the need to explore alternative immune cells for cancer targeting. In this regard, natural killer (NK) cells have been extensively studied in cellular immunotherapy and were found to exert cytotoxic effects without being restricted by human leukocyte antigen and have a lower risk of causing graft-versus-host disease; making them favorable for the development of readily available "off-the-shelf" products. Clinical trials utilizing unedited NK cells or reprogrammed NK cells have shown early signs of their effectiveness against tumors. However, limitations, including limited in vivo persistence and expansion potential, remained. To enhance the antitumor function of NK cells, advanced gene-editing technologies and combination approaches have been explored. In this review, we summarize current clinical trials of antitumor NK cell therapy, provide an overview of innovative strategies for reprogramming NK cells, which include improvements in persistence, cytotoxicity, trafficking and the ability to counteract the immunosuppressive tumor microenvironment, and also discuss some potential combination therapies.

6.
BMC Genomics ; 25(1): 465, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38741087

ABSTRACT

BACKGROUND: The early 2 factor (E2F) family is characterized as a kind of transcription factor that plays an important role in cell division, DNA damage repair, and cell size regulation. However, its stress response has not been well revealed. RESULTS: In this study, ZmE2F members were comprehensively identified in the maize genome, and 21 ZmE2F genes were identified, including eight E2F subclade members, seven DEL subfamily genes, and six DP genes. All ZmE2F proteins possessed the DNA-binding domain (DBD) characterized by conserved motif 1 with the RRIYD sequence. The ZmE2F genes were unevenly distributed on eight maize chromosomes, showed diversity in gene structure, expanded by gene duplication, and contained abundant stress-responsive elements in their promoter regions. Subsequently, the ZmE2F6 gene was cloned and functionally verified in drought response. The results showed that the ZmE2F6 protein interacted with ZmPP2C26, localized in the nucleus, and responded to drought treatment. The overexpression of ZmE2F6 enhanced drought tolerance in transgenic Arabidopsis with longer root length, higher survival rate, and biomass by upregulating stress-related gene transcription. CONCLUSIONS: This study provides novel insights into a greater understanding and functional study of the E2F family in the stress response.


Subject(s)
Droughts , Gene Expression Regulation, Plant , Plant Proteins , Stress, Physiological , Transcription Factors , Zea mays , Zea mays/genetics , Zea mays/metabolism , Stress, Physiological/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Phylogeny , Plants, Genetically Modified , Arabidopsis/genetics , Promoter Regions, Genetic , Chromosomes, Plant/genetics
7.
Br J Cancer ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38906969

ABSTRACT

BACKGROUND: Lipid droplet formation is a prominent histological feature in clear cell renal cell carcinoma (ccRCC), but the significance and mechanisms underlying lipid droplet accumulation remain unclear. METHODS: Expression and clinical significance of MT1G in ccRCC were analyzed by using TCGA data, GEO data and scRNASeq data. MT1G overexpression or knockdown ccRCC cell lines were constructed and in situ ccRCC model, lung metastasis assay, metabolomics and lipid droplets staining were performed to explore the role of MT1G on lipid droplet accumulation in ccRCC. RESULTS: Initially, we observed low MT1G expression in ccRCC tissues, whereas high MT1G expression correlated with advanced disease stage and poorer prognosis. Elevated MT1G expression promoted ccRCC growth and metastasis both in vitro and in vivo. Mechanistically, MT1G significantly suppressed acylcarnitine levels and downstream tricarboxylic acid (TCA) cycle activity, resulting in increased fatty acid and lipid accumulation without affecting cholesterol metabolism. Notably, MT1G inhibited H3K14 trimethylation (H3K14me3) modification. Under these conditions, MT1G-mediated H3K14me3 was recruited to the CPT1B promoter through direct interaction with specific promoter regions, leading to reduced CPT1B transcription and translation. CONCLUSIONS: Our study unveils a novel mechanism of lipid droplet accumulation in ccRCC, where MT1G inhibits CPT1B expression through modulation of H3K14 trimethylation, consequently enhancing lipid droplet accumulation and promoting ccRCC progression. Graphical abstract figure Schematic diagram illustrating MT1G/H3K14me3/CPT1B-mediated lipid droplet accumulation promoted ccRCC progression via FAO inhibition.

8.
Biochem Cell Biol ; 102(1): 85-95, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37921219

ABSTRACT

Acute myeloid leukemia (AML) is one of the hematological malignancies with a high recurrence rate. WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) is identified as a pivotal regulator of tumor progression. This study aimed to assess the possible role of WWP2 in AML. Analysis of the GEPIA database indicated an elevated WWP2 expression in AML. We established stable WWP2-overexpressed or WWP2-silenced cells using lentivirus loaded with cDNA encoding WWP2 mRNA or shRNA targeting WWP2. Notably, WWP2 overexpression facilitated cell proliferation and cell cycle progression, which was manifested as the increase of colony formation number, S-phase percentage and cell cycle related protein levels. As observed, WWP2 knockdown presented opposite effects, leading to inhibition of tumorigenicity. Strikingly, WWP2 knockdown induced apoptosis, accompanied by upregulation of pro-apoptosis proteins cleaved caspase-9, Bax and cleaved caspase-3 and downregulation of anti-apoptosis protein Bcl-2. Functionally, we further confirmed that WWP2 overexpression enhanced the NF-κB signaling and upregulated the levels of downstream genes, which may contribute to aggravating the development of AML. More importantly, by co-immunoprecipitation assay, we verified that WWP2 bound to NF-κB-repressing factor (NKRF) and promoted NKRF ubiquitylation. Dramatically, NKRF overexpression abolished the role of WWP2 in facilitating the process of AML. Overall, our observations confirm that WWP2 exerts a critical role in the tumorigenicity of AML, and NKRF is regarded as an essential factor in the WWP2-mediated AML progression. WWP2 may be proposed as a promising target of AML.


Subject(s)
Leukemia, Myeloid, Acute , NF-kappa B , Humans , Apoptosis , Apoptosis Regulatory Proteins/genetics , Cell Line, Tumor , Cell Proliferation , Leukemia, Myeloid, Acute/genetics , NF-kappa B/metabolism , Signal Transduction/genetics , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination
9.
Magn Reson Med ; 91(3): 942-954, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37899691

ABSTRACT

PURPOSE: To confirm that CrCEST in muscle exhibits a slow-exchanging process, and to obtain high-resolution amide, creatine (Cr), and phosphocreatine (PCr) maps of skeletal muscle using a POlynomial and Lorentzian Line-shape Fitting (PLOF) CEST at 3T. METHODS: We used dynamic changes in PCr/CrCEST of mouse hindlimb before and after euthanasia to assign the Cr and PCr CEST peaks in the Z-spectrum at 3T and to obtain the optimum saturation parameters. Segmented 3D EPI was employed to obtain multi-slice amide, PCr, and Cr CEST maps of human skeletal muscle. Subsequently, the PCrCEST maps were calibrated using the PCr concentrations determined by 31 P MRS. RESULTS: A comparison of the Z-spectra in mouse hindlimb before and after euthanasia indicated that CrCEST is a slow-exchanging process in muscle (<150.7 s-1 ). This allowed us to simultaneously extract PCr/CrCEST signals at 3T using the PLOF method. We determined optimal B1 values ranging from 0.3 to 0.6 µT for CrCEST in muscle and 0.3-1.2 µT for PCrCEST. For the study on human calf muscle, we determined an optimum saturation time of 2 s for both PCr/CrCEST (B1 = 0.6 µT). The PCr/CrCEST using 3D EPI were found to be comparable to those obtained using turbo spin echo (TSE). (3D EPI/TSE PCr: (2.6 ± 0.3) %/(2.3 ± 0.1) %; Cr: (1.3 ± 0.1) %/(1.4 ± 0.07) %). CONCLUSIONS: Our study showed that in vivo CrCEST is a slow-exchanging process. Hence, amide, Cr, and PCr CEST in the skeletal muscle can be mapped simultaneously at 3T by PLOF CEST.


Subject(s)
Creatine , Magnetic Resonance Imaging , Humans , Animals , Mice , Phosphocreatine , Magnetic Resonance Imaging/methods , Muscle, Skeletal/diagnostic imaging , Amides
10.
Magn Reson Med ; 91(1): 51-60, 2024 01.
Article in English | MEDLINE | ID: mdl-37814487

ABSTRACT

PURPOSE: To assess the feasibility of CEST-based creatine (Cr) mapping in brain at 3T using the guanidino (Guan) proton resonance. METHODS: Wild type and knockout mice with guanidinoacetate N-methyltransferase deficiency and low Cr and phosphocreatine (PCr) concentrations in the brain were used to assign the Cr and protein-based arginine contributions to the GuanCEST signal at 2.0 ppm. To quantify the Cr proton exchange rate, two-step Bloch-McConnell fitting was used to fit the extracted CrCEST line-shape and multi-B1 Z-spectral data. The pH response of GuanCEST was simulated to demonstrate its potential for pH mapping. RESULTS: Brain Z-spectra of wild type and guanidinoacetate N-methyltransferase deficiency mice show a clear Guan proton peak at 2.0 ppm at 3T. The CrCEST signal contributes ∼23% to the GuanCEST signal at B1 = 0.8 µT, where a maximum CrCEST effect of 0.007 was detected. An exchange rate range of 200-300 s-1 was estimated for the Cr Guan protons. As revealed by the simulation, an elevated GuanCEST in the brain is observed when B1 is less than 0.4 µT at 3T, when intracellular pH reduces by 0.2. Conversely, the GuanCEST decreases when B1 is greater than 0.4 µT with the same pH drop. CONCLUSIONS: CrCEST mapping is possible at 3T, which has potential for detecting intracellular pH and Cr concentration in brain.


Subject(s)
Creatine , Protons , Mice , Animals , Creatine/analysis , Guanidinoacetate N-Methyltransferase , Magnetic Resonance Imaging , Brain/diagnostic imaging , Mice, Knockout
11.
Magn Reson Med ; 92(4): 1456-1470, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38748853

ABSTRACT

PURPOSE: To develop a 3D, high-sensitivity CEST mapping technique based on the 3D stack-of-spirals (SOS) gradient echo readout, the proposed approach was compared with conventional acquisition techniques and evaluated for its efficacy in concurrently mapping of guanidino (Guan) and amide CEST in human brain at 3 T, leveraging the polynomial Lorentzian line-shape fitting (PLOF) method. METHODS: Saturation time and recovery delay were optimized to achieve maximum CEST time efficiency. The 3DSOS method was compared with segmented 3D EPI (3DEPI), turbo spin echo, and gradient- and spin-echo techniques. Image quality, temporal SNR (tSNR), and test-retest reliability were assessed. Maps of Guan and amide CEST derived from 3DSOS were demonstrated on a low-grade glioma patient. RESULTS: The optimized recovery delay/saturation time was determined to be 1.4/2 s for Guan and amide CEST. In addition to nearly doubling the slice number, the gradient echo techniques also outperformed spin echo sequences in tSNR: 3DEPI (193.8 ± 6.6), 3DSOS (173.9 ± 5.6), and GRASE (141.0 ± 2.7). 3DSOS, compared with 3DEPI, demonstrated comparable GuanCEST signal in gray matter (GM) (3DSOS: [2.14%-2.59%] vs. 3DEPI: [2.15%-2.61%]), and white matter (WM) (3DSOS: [1.49%-2.11%] vs. 3DEPI: [1.64%-2.09%]). 3DSOS also achieves significantly higher amideCEST in both GM (3DSOS: [2.29%-3.00%] vs. 3DEPI: [2.06%-2.92%]) and WM (3DSOS: [2.23%-2.66%] vs. 3DEPI: [1.95%-2.57%]). 3DSOS outperforms 3DEPI in terms of scan-rescan reliability (correlation coefficient: 3DSOS: 0.58-0.96 vs. 3DEPI: -0.02 to 0.75) and robustness to motion as well. CONCLUSION: The 3DSOS CEST technique shows promise for whole-cerebrum CEST imaging, offering uniform contrast and robustness against motion artifacts.


Subject(s)
Amides , Brain , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Humans , Amides/chemistry , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Brain/diagnostic imaging , Reproducibility of Results , Echo-Planar Imaging/methods , Glioma/diagnostic imaging , Algorithms , Signal-To-Noise Ratio , Brain Neoplasms/diagnostic imaging , Adult , Image Processing, Computer-Assisted/methods , Male , Female , Guanidine/chemistry
12.
Cardiovasc Diabetol ; 23(1): 170, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38750553

ABSTRACT

OBJECTIVE: Although the TyG index is a reliable predictor of insulin resistance (IR) and cardiovascular disease, its effectiveness in predicting major adverse cardiac events in hospitalized acute coronary syndrome (ACS) patients has not been validated in large-scale studies. In this study, we aimed to explore the association between the TyG index and the occurrence of MACEs during hospitalization. METHODS: We recruited ACS patients from the CCC-ACS (Improving Cardiovascular Care in China-ACS) database and calculated the TyG index using the formula ln(fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2). These patients were classified into four groups based on quartiles of the TyG index. The primary endpoint was the occurrence of MACEs during hospitalization, encompassing all-cause mortality, cardiac arrest, myocardial infarction (MI), and stroke. We performed Cox proportional hazards regression analysis to clarify the correlation between the TyG index and the risk of in-hospital MACEs among patients diagnosed with ACS. Additionally, we explored this relationship across various subgroups. RESULTS: A total of 101,113 patients were ultimately included, and 2759 in-hospital MACEs were recorded, with 1554 (49.1%) cases of all-cause mortality, 601 (21.8%) cases of cardiac arrest, 251 (9.1%) cases of MI, and 353 (12.8%) cases of stroke. After adjusting for confounders, patients in TyG index quartile groups 3 and 4 showed increased risks of in-hospital MACEs compared to those in quartile group 1 [HR = 1.253, 95% CI 1.121-1.400 and HR = 1.604, 95% CI 1.437-1.791, respectively; p value for trend < 0.001], especially in patients with STEMI or renal insufficiency. Moreover, we found interactions between the TyG index and age, sex, diabetes status, renal insufficiency status, and previous PCI (all p values for interactions < 0.05). CONCLUSIONS: In patients with ACS, the TyG index was an independent predictor of in-hospital MACEs. Special vigilance should be exercised in females, elderly individuals, and patients with renal insufficiency.


Subject(s)
Acute Coronary Syndrome , Biomarkers , Blood Glucose , Databases, Factual , Predictive Value of Tests , Triglycerides , Humans , Acute Coronary Syndrome/blood , Acute Coronary Syndrome/mortality , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/therapy , Acute Coronary Syndrome/epidemiology , Female , Male , Middle Aged , Aged , China/epidemiology , Blood Glucose/metabolism , Triglycerides/blood , Biomarkers/blood , Risk Assessment , Risk Factors , Time Factors , Prognosis , Myocardial Infarction/blood , Myocardial Infarction/diagnosis , Myocardial Infarction/mortality , Myocardial Infarction/epidemiology , Myocardial Infarction/therapy , Heart Arrest/blood , Heart Arrest/mortality , Heart Arrest/diagnosis , Heart Arrest/therapy , Heart Arrest/epidemiology , Stroke/blood , Stroke/mortality , Stroke/diagnosis , Stroke/epidemiology , Stroke/therapy , Hospitalization , Hospital Mortality
13.
NMR Biomed ; 37(8): e5130, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38491754

ABSTRACT

Chemical exchange saturation transfer (CEST) MRI is a molecular imaging tool that provides physiological information about tissues, making it an invaluable tool for disease diagnosis and guided treatment. Its clinical application requires the acquisition of high-resolution images capable of accurately identifying subtle regional changes in vivo, while simultaneously maintaining a high level of spectral resolution. However, the acquisition of such high-resolution images is time consuming, presenting a challenge for practical implementation in clinical settings. Among several techniques that have been explored to reduce the acquisition time in MRI, deep-learning-based super-resolution (DLSR) is a promising approach to address this problem due to its adaptability to any acquisition sequence and hardware. However, its translation to CEST MRI has been hindered by the lack of the large CEST datasets required for network development. Thus, we aim to develop a DLSR method, named DLSR-CEST, to reduce the acquisition time for CEST MRI by reconstructing high-resolution images from fast low-resolution acquisitions. This is achieved by first pretraining the DLSR-CEST on human brain T1w and T2w images to initialize the weights of the network and then training the network on very small human and mouse brain CEST datasets to fine-tune the weights. Using the trained DLSR-CEST network, the reconstructed CEST source images exhibited improved spatial resolution in both peak signal-to-noise ratio and structural similarity index measure metrics at all downsampling factors (2-8). Moreover, amide CEST and relayed nuclear Overhauser effect maps extrapolated from the DLSR-CEST source images exhibited high spatial resolution and low normalized root mean square error, indicating a negligible loss in Z-spectrum information. Therefore, our DLSR-CEST demonstrated a robust reconstruction of high-resolution CEST source images from fast low-resolution acquisitions, thereby improving the spatial resolution and preserving most Z-spectrum information.


Subject(s)
Brain , Deep Learning , Magnetic Resonance Imaging , Magnetic Resonance Imaging/methods , Humans , Brain/diagnostic imaging , Image Processing, Computer-Assisted/methods , Animals , Signal-To-Noise Ratio , Mice
14.
Arch Biochem Biophys ; : 110102, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39029644

ABSTRACT

Abdominal aortic aneurysm (AAA) is a dangerous condition affecting the aorta. Macrophage pyroptosis, phenotypic transformation, and apoptosis of aortic smooth muscle cells (ASMCs) are pivotal mechanisms in AAA pathogenesis. This study explores how Gasdermin B (GSDMB) regulates macrophage non-canonical pyroptosis and its impact on the phenotypic transformation and apoptosis of ASMCs, thereby unveiling the role of GSDMB in AAA pathogenesis. Immunofluorescence analysis was used to assess the expression levels and localization of GSDMB, cysteinyl aspartate-specific protease-4 (Caspase-4), and N-terminal of cleaved GSDMD (N-GSDMD) in AAA tissues. A cell model that mimics macrophage non-canonical pyroptosis was established by treating THP-1 cells with lipopolysaccharide (LPS). THP-1 cells with reduced or increased GSDMB were generated using small interfering RNA (siRNA) or plasmids. Co-culture experiments involving THP-1 cells and HASMCs were conducted to explore the impact of GSDMB on HASMCs. The mitochondrial reactive oxygen species (mtROS) scavenger Mito-TEMPO lowered mtROS levels in THP-1 cells. Our findings revealed that GSDMB was significantly upregulated in AAA macrophages, which was accompanied by robust non-canonical pyroptosis. THP-1 cells showed non-canonical pyroptosis in response to LPS, which was accompanied by an increase in GSDMB. Further research demonstrated that altering GSDMB, either by knockdown or overexpression, can affect macrophage non-canonical pyroptosis as well as the phenotypic transformation and apoptosis of HASMCs. LPS-induced non-canonical pyroptosis in THP-1 cells was associated with an increase in mtROS, whereas Mito-TEMPO effectively decreased non-canonical pyroptosis and the expression of GSDMB. These findings suggest that GSDMB plays a role in AAA macrophage non-canonical pyroptosis, which influences the phenotypic transformation and apoptosis of HASMCs. The mtROS-Dynamin-Related Protein 1 (Drp1) axis is likely to regulate the GSDMB-mediated non-canonical pyroptosis.

15.
J Magn Reson Imaging ; 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38363125

ABSTRACT

BACKGROUND: For patients with PI-RADS v2.1 ≥ 3, prostate biopsy is strongly recommended. Due to the unsatisfactory positive rate of biopsy, improvements in clinically significant prostate cancer (csPCa) risk assessments are required. PURPOSE: To develop and validate machine learning (ML) models based on clinical and imaging parameters for csPCa detection in patients with PI-RADS v2.1 ≥ 3. STUDY TYPE: Retrospective. SUBJECTS: One thousand eighty-three patients with PI-RADS v2.1 ≥ 3, randomly split into training (70%, N = 759) and validation (30%, N = 324) datasets, and 147 patients enrolled prospectively for testing. FIELD STRENGTH/SEQUENCE: 3.0 T scanners/T2-weighted fast spin echo sequence and DWI with diffusion-weighted single-shot gradient echo planar imaging sequence. ASSESSMENT: The factors evaluated for csPCa detection were age, prostate specific antigen, prostate volume, and the diameter and location of the index lesion, PI-RADSv2.1. Five ML models for csPCa detection were developed: logistic regression (LR), extreme gradient boosting, random forest (RF), decision tree, and support vector machines. The csPCa was defined as Gleason grade ≥2. STATISTICAL TESTS: Univariable and multivariable LR analyses to identify parameters associated with csPCa. Area under the receiver operating characteristic curve (AUC), Brier score, and DeLong test were used to assess and compare the csPCa diagnostic performance with the LR model. The significance level was defined as 0.05. RESULTS: The RF model exhibited the highest AUC (0.880-0.904) and lowest Brier score (0.125-0.133) among the ML models in the validation and testing cohorts, however, there was no difference when compared to the LR model (P = 0.453 and 0.548). The sensitivity and negative predictive values in the validation and testing cohorts were 93.8%-97.6% and 82.7%-95.1%, respectively, at a threshold of 0.450 (99% sensitivity of the RF model). DATA CONCLUSION: The RF model might help for assessing the risk of csPCa and preventing overdiagnosis and unnecessary biopsy for men with PI-RADSv2.1 ≥ 3. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

16.
Arch Microbiol ; 206(7): 316, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38904699

ABSTRACT

Cotinine, the primary metabolite of nicotine in the human body, is an emerging pollutant in aquatic environments. It causes environmental problems and is harmful to the health of humans and other mammals; however, the mechanisms of its biodegradation have been elucidated incompletely. In this study, a novel Gram-negative strain that could degrade and utilize cotinine as a sole carbon source was isolated from municipal wastewater samples, and its cotinine degradation characteristics and kinetics were determined. Pseudomonas sp. JH-2 was able to degrade 100 mg/L (0.56 mM) of cotinine with high efficiency within 5 days at 30 ℃, pH 7.0, and 1% NaCl. Two intermediates, 6-hydroxycotinine and 6-hydroxy-3-succinoylpyridine (HSP), were identified by high-performance liquid chromatography and liquid chromatograph mass spectrometer. The draft whole genome sequence of strain JH-2 was obtained and analyzed to determine genomic structure and function. No homologs of proteins predicted in Nocardioides sp. JQ2195 and reported in nicotine degradation Pyrrolidine pathway were found in strain JH-2, suggesting new enzymes that responsible for cotinine catabolism. These findings provide meaningful insights into the biodegradation of cotinine by Gram-negative bacteria.


Subject(s)
Biodegradation, Environmental , Cotinine , Pseudomonas , Wastewater , Pseudomonas/metabolism , Pseudomonas/genetics , Pseudomonas/isolation & purification , Pseudomonas/classification , Cotinine/metabolism , Cotinine/analogs & derivatives , Wastewater/microbiology , Nicotine/metabolism , Nicotine/analogs & derivatives , Pyridines/metabolism , Genome, Bacterial , Phylogeny , Succinates
17.
Article in English | MEDLINE | ID: mdl-38668744

ABSTRACT

A Gram-stain-negative bacterium, designated LG-4T, was isolated from sediment of Qiantang River in Zhejiang Province, PR China. Cells were strictly aerobic, non-spore-forming, non-motile and short-rod-shaped (1.0-1.2 µm long and 0.7-0.8 µm wide). Growth occurred at 15-42 °C (optimum, 30 °C), at pH 5.0-9.0 (pH 7.0) and at 0-2.0 % (w/v) NaCl (optimum, 0.5 % NaCl). Strain LG-4T showed 95.75-96.90 % 16S rRNA gene sequence similarity to various type strains of the genera Tabrizicola, Pseudotabrizicola, Phaeovulum, Rhodobacter and Wagnerdoeblera of the family Paracoccaceae, and the most closely related strain was Tabrizicola soli ZQBWT (96.90 % similarity). The phylogenomic tree showed that strain LG-4T clustered in the family Paracoccaceae and was positioned outside of the clade composed of the genera Wagnerdoeblera and Falsigemmobacter. The average nucleotide identity and digital DNA-DNA hybridization values between strain LG-4T and the related type strains were in the range of 74.19-77.56 % and 16.70-25.80 %, respectively. The average amino acid identity (AAI) values between strain LG-4T and related type strains of the family Paracoccaceae were 60.94-69.73 %, which are below the genus boundary (70 %). The evolutionary distance (ED) values between LG-4T and the related genera of the family Paracoccaceae were 0.21-0.34, which are within the recommended standard (≥0.21-0.23) for defining a novel genus in the family Paracoccaceae. The predominant cellular fatty acids were C18 : 1 ω7c, C19 : 0 cyclo ω8c, C18 : 0 and C16 : 0, the isoprenoid quinone was Q-10, and the major polar lipids were phospholipid, phosphatidylglycerol, phosphatidylcholine, aminolipid and two unknown polar lipids. The genome size was 4.7 Mb with 68.6 mol% G+C content. On the basis of distinct phylogenetic relationships, low AAI values and high ED values, and differential phenotypic, physiological and biochemical characteristics, strain LG-4T represents a novel species of a new genus in the family Paracoccaceae, for which the name Ruixingdingia sedimenti gen. nov., sp. nov. is proposed. The type strain is LG-4T (=MCCC 1K08849T=KCTC 8136T).


Subject(s)
Bacterial Typing Techniques , Base Composition , DNA, Bacterial , Fatty Acids , Geologic Sediments , Nucleic Acid Hybridization , Phylogeny , RNA, Ribosomal, 16S , Rivers , Sequence Analysis, DNA , RNA, Ribosomal, 16S/genetics , Fatty Acids/chemistry , Fatty Acids/analysis , DNA, Bacterial/genetics , China , Geologic Sediments/microbiology , Rivers/microbiology , Phospholipids/analysis , Ubiquinone/analogs & derivatives
18.
Inflamm Res ; 73(3): 345-362, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38157008

ABSTRACT

OBJECTIVES: Colitis is a global disease usually accompanied by intestinal epithelial damage and intestinal inflammation, and an increasing number of studies have found natural products to be highly effective in treating colitis. Anemoside B4 (AB4), an abundant saponin isolated from Pulsatilla chinensis (Bunge), which was found to have strong anti-inflammatory activity. However, the exact molecular mechanisms and direct targets of AB4 in the treatment of colitis remain to be discovered. METHODS: The anti-inflammatory activities of AB4 were verified in LPS-induced cell models and 2, 4, 6-trinitrobenzene sulfonic (TNBS) or dextran sulfate sodium (DSS)-induced colitis mice and rat models. The molecular target of AB4 was identified by affinity chromatography analysis using chemical probes derived from AB4. Experiments including proteomics, molecular docking, biotin pull-down, surface plasmon resonance (SPR), and cellular thermal shift assay (CETSA) were used to confirm the binding of AB4 to its molecular target. Overexpression of pyruvate carboxylase (PC) and PC agonist were used to study the effects of PC on the anti-inflammatory and metabolic regulation of AB4 in vitro and in vivo. RESULTS: AB4 not only significantly inhibited LPS-induced NF-κB activation and increased ROS levels in THP-1 cells, but also suppressed TNBS/DSS-induced colonic inflammation in mice and rats. The molecular target of AB4 was identified as PC, a key enzyme related to fatty acid, amino acid and tricarboxylic acid (TCA) cycle. We next demonstrated that AB4 specifically bound to the His879 site of PC and altered the protein's spatial conformation, thereby affecting the enzymatic activity of PC. LPS activated NF-κB pathway and increased PC activity, which caused metabolic reprogramming, while AB4 reversed this phenomenon by inhibiting the PC activity. In vivo studies showed that diisopropylamine dichloroacetate (DADA), a PC agonist, eliminated the therapeutic effects of AB4 by changing the metabolic rearrangement of intestinal tissues in colitis mice. CONCLUSION: We identified PC as a direct cellular target of AB4 in the modulation of inflammation, especially colitis. Moreover, PC/pyruvate metabolism/NF-κB is crucial for LPS-driven inflammation and oxidative stress. These findings shed more light on the possibilities of PC as a potential new target for treating colitis.


Subject(s)
Colitis , Saponins , Rats , Mice , Animals , Pyruvate Carboxylase/metabolism , NF-kappa B/metabolism , Lipopolysaccharides/pharmacology , Molecular Docking Simulation , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Inflammation/metabolism , Saponins/pharmacology , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Macrophages/metabolism , Dextran Sulfate/adverse effects , Dextran Sulfate/metabolism , Mice, Inbred C57BL , Disease Models, Animal
19.
Dis Colon Rectum ; 67(2): 333-338, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37962124

ABSTRACT

BACKGROUND: Parastomal hernia is a major long-term complication after abdominoperineal resection. Extraperitoneal colostomy has been proposed as an effective step for parastomal hernia prevention, but it has not been widely used as it is technically demanding and time-consuming. We proposed a modified approach for extraperitoneal colostomy creation by entering the extraperitoneal space through the arcuate line of the posterior rectus sheath. OBJECTIVE: To evaluate the safety, difficulty, and efficacy of long-term parastomal hernia prevention of the modified approach for extraperitoneal colostomy creation compared with the conventional transperitoneal colostomy approach. DESIGN: This was a retrospective evaluation of a surgical and video database. SETTINGS: This was a single-institution retrospective study. PATIENTS: Clinical data of 74 patients who underwent laparoscopic abdominoperineal resection surgery from January 2019 to January 2020 in the Department of General Surgery, Qilu Hospital of Shandong University, were retrospectively reviewed. MAIN OUTCOME MEASURES: Baseline characteristics, time required for colostomy creation (from skin incision to colostomy maturation), perioperative complications, and long-term colostomy-related complications were compared. RESULTS: Baseline characteristics did not differ between the 2 approaches. The BMI level ranged from 19.5 to 29.4 for patients undergoing extraperitoneal approach. Time required for colostomy creation median [interquartile range], (22 [21-25] minutes for extraperitoneal vs 23 [21-25] minutes for transperitoneal, p = 0.861) were comparable between the 2 approaches. The cumulative incidence of parastomal hernia was significantly greater with transperitoneal colostomy than extraperitoneal colostomy at 2 and 3 years postoperatively (16.2% vs 0%, p = 0.025, and 21.6% vs 0%, p = 0.005). The remaining perioperative complications and long-term colostomy-related complications did not differ between the 2 approaches. LIMITATIONS: This study is limited by its retrospective design and small sample size. CONCLUSIONS: The modified approach for extraperitoneal colostomy creation is safe, technically simple, and effective for long-term parastomal hernia prevention in patients with a BMI of 19.5 to 29.4.


Subject(s)
Hernia, Ventral , Incisional Hernia , Laparoscopy , Proctectomy , Humans , Colostomy/adverse effects , Retrospective Studies , Laparoscopy/adverse effects , Incisional Hernia/prevention & control , Incisional Hernia/surgery , Proctectomy/adverse effects , Hernia, Ventral/etiology , Hernia, Ventral/prevention & control , Surgical Mesh/adverse effects
20.
J Org Chem ; 2024 May 08.
Article in English | MEDLINE | ID: mdl-38720168

ABSTRACT

Tracking carboxylesterases (CESs) through noninvasive and dynamic imaging is of great significance for diagnosing and treating CES-related metabolic diseases. Herein, three BODIPY-based fluorescent probes with a pyridine unit quaternarized via an acetoxybenzyl group were designed and synthesized to detect CESs based on the photoinduced electron transfer process. Notably, among these probes, BDPN2-CES exhibited a remarkable 182-fold fluorescence enhancement for CESs within 10 min. Moreover, BDPN2-CES successfully enabled real-time imaging of endogenous CES variations in living cells. Using BDPN2-CES, a visual high-throughput screening method for CES inhibitors was established, culminating in the discovery of an efficient inhibitor, WZU-13, sourced from a chemical library. These findings suggest that BDPN2-CES could provide a new avenue for diagnosing CES-related diseases, and WZU-13 emerges as a promising therapeutic candidate for CES-overexpression pathological processes.

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