Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 361
Filter
Add more filters

Publication year range
1.
Cell ; 185(8): 1389-1401.e18, 2022 04 14.
Article in English | MEDLINE | ID: mdl-35344711

ABSTRACT

The effectiveness of SARS-CoV-2 vaccines and therapeutic antibodies have been limited by the continuous emergence of viral variants and by the restricted diffusion of antibodies from circulation into the sites of respiratory virus infection. Here, we report the identification of two highly conserved regions on the Omicron variant receptor-binding domain recognized by broadly neutralizing antibodies. Furthermore, we generated a bispecific single-domain antibody that was able to simultaneously and synergistically bind these two regions on a single Omicron variant receptor-binding domain as revealed by cryo-EM structures. We demonstrated that this bispecific antibody can be effectively delivered to lung via inhalation administration and exhibits exquisite neutralization breadth and therapeutic efficacy in mouse models of SARS-CoV-2 infections. Importantly, this study also deciphered an uncommon and highly conserved cryptic epitope within the spike trimeric interface that may have implications for the design of broadly protective SARS-CoV-2 vaccines and therapeutics.


Subject(s)
COVID-19 Vaccines , Single-Domain Antibodies , Administration, Inhalation , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 , COVID-19 Vaccines/administration & dosage , Disease Models, Animal , Humans , Mice , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry
2.
Mol Cell ; 82(6): 1169-1185.e7, 2022 03 17.
Article in English | MEDLINE | ID: mdl-35202573

ABSTRACT

Polycomb group (PcG) proteins are essential for post-implantation development by depositing repressive histone modifications at promoters, mainly CpG islands (CGIs), of developmental regulator genes. However, promoter PcG marks are erased after fertilization and de novo established in peri-implantation embryos, coinciding with the transition from naive to primed pluripotency. Nevertheless, the molecular basis for this establishment remains unknown. In this study, we show that the expression of the long KDM2B isoform (KDM2BLF), which contains the demethylase domain, is specifically induced at peri-implantation and that its H3K36me2 demethylase activity is required for PcG enrichment at CGIs. Moreover, KDM2BLF interacts with BRG1/BRM-associated factor (BAF) and stabilizes BAF occupancy at CGIs for subsequent gain of accessibility, which precedes PcG enrichment. Consistently, KDM2BLF inactivation results in significantly delayed post-implantation development. In summary, our data unveil dynamic chromatin configuration of CGIs during exit from naive pluripotency and provide a conceptual framework for the spatiotemporal establishment of PcG functions.


Subject(s)
Chromatin , Drosophila Proteins , CpG Islands , Drosophila Proteins/metabolism , Histone Code , Polycomb-Group Proteins/genetics , Polycomb-Group Proteins/metabolism , Promoter Regions, Genetic
3.
PLoS Biol ; 20(1): e3001518, 2022 01.
Article in English | MEDLINE | ID: mdl-35041644

ABSTRACT

Lipid droplets (LDs) have increasingly been recognized as an essential organelle for eukaryotes. Although the biochemistry of lipid synthesis and degradation is well characterized, the regulation of LD dynamics, including its formation, maintenance, and secretion, is poorly understood. Here, we report that mice lacking Occludin (Ocln) show defective lipid metabolism. We show that LDs were larger than normal along its biogenesis and secretion pathway in Ocln null mammary cells. This defect in LD size control did not result from abnormal lipid synthesis or degradation; rather, it was because of secretion failure during the lactation stage. We found that OCLN was located on the LD membrane and was bound to essential regulators of lipid secretion, including BTN1a1 and XOR, in a C-terminus-dependent manner. Finally, OCLN was a phosphorylation target of Src kinase, whose loss causes lactation failure. Together, we demonstrate that Ocln is a downstream target of Src kinase and promotes LD secretion by binding to BTN1a1 and XOR.


Subject(s)
Lipid Droplets/physiology , Lipid Metabolism , Mammary Glands, Animal/metabolism , Occludin/metabolism , Animals , Butyrophilins/metabolism , Female , Lactation/metabolism , Mice , Milk/metabolism , Occludin/genetics , src-Family Kinases/antagonists & inhibitors , src-Family Kinases/metabolism
4.
Neurobiol Dis ; 195: 106497, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38583641

ABSTRACT

OBJECTIVES: To elucidate and compare the genetic, clinical, ancillary diagnostic, and pathological characteristics across different Gerstmann-Sträussler-Scheinker disease (GSS) phenotypes and explore the underlying causes of the phenotypic heterogeneities. METHODS: The genetic, clinical, ancillary diagnostic, and pathological profiles of GSS patients reported in the literature were obtained and analyzed. Additionally, 3 patients with genetically confirmed GSS from our unit were included. Based on clinical presentation, patients were classified into typical GSS, Creutzfeldt-Jakob disease (CJD)-like GSS, GSS with dementia, and other categories. RESULTS: A total of 329 GSS cases were included with a 1.13:1 female-to-male ratio, median onset age 44, and median duration 4 years. Of the 294 categorized patients, 50.7% had typical GSS, 24.8% showed CJD-like GSS, and 16.3% presented with GSS with dementia. Clinical classification varied significantly based on genotype, with P102L more common in typical GSS and A117V prevalent in CJD-like GSS. Polymorphism at codon 129 has no effect on GSS phenotype, but the 129 M allele acts as a protective factor in GSS patients in Asia and North America. Moderate to severe spongiform degeneration and the presence of PK-resistant small fragments migrating at <11 kDa on electrophoretic gels along with PrP27-30 fragments were more prevalent in CJD-like GSS phenotype, while hyperphosphorylated tau protein co-deposition tends to be characteristic of typical GSS and GSS with dementia. CONCLUSION: This study reveals GSS's intricate nature, showing significant variations in clinical presentations, diagnostic findings, and pathological features. Mutation sites and pathological changes play crucial roles in determining the GSS clinical heterogeneity.


Subject(s)
Gerstmann-Straussler-Scheinker Disease , Phenotype , Humans , Gerstmann-Straussler-Scheinker Disease/genetics , Gerstmann-Straussler-Scheinker Disease/pathology , Male , Female , Middle Aged , Adult , Aged
5.
Anal Chem ; 96(26): 10851-10859, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38912707

ABSTRACT

Mitochondrial Membrane Chromatography (MMC) is a bioaffinity chromatography technique developed to study the interaction between target proteins embedded in the mitochondrial membrane and their ligand compounds. However, the MMC stationary phases (MMSP) prepared by chemical immobilization are prone to nonspecific binding in candidate agent screening inevitably. To address these challenges, Twin Strep-Tag/Strep Tactin was employed to establish a specific affinity system in the present study. We prepared a carnitine palmitoyltransferase 1A (CPT1A) MMSP by specifically linking Strep-tactin-modified silica gel with the Twin Strep-Tag on the CPT1A-oriented mitochondrial membrane. This Twin Strep-Tag/Strep Tactin modified CPT1A/MMC method exhibited remarkably better retention behavior, longer stationary phase lifespan, and higher screening specificity compared with previous MMC systems with glutaraldehyde immobilization. We adopted the CPT1A-specific MMC system in screening CPT1A ligands from traditional Chinese medicines, and successfully identified novel candidate ligands: ononin, isoliquiritigenin, and aloe-emodin, from Glycyrrhiza uralensis Fisch and Senna tora (L.) Roxb extracts. Biological assessments illustrated that the compounds screened promote CPT1A enzyme activity without affecting CPT1A protein expression, as well as effectively reduce the lipid droplets and triglyceride levels in the high fat induction HepG2 cells. The results suggest that we have developed an MMC system, which is promising for studying the bioaffinity of mitochondrial membrane proteins to candidate compounds. This system provides a platform for a key step in mitochondrial medicine discovery, especially for bioactive molecule screening from complex herbal extracts.


Subject(s)
Carnitine O-Palmitoyltransferase , Lipid Metabolism , Mitochondrial Membranes , Humans , Carnitine O-Palmitoyltransferase/metabolism , Lipid Metabolism/drug effects , Mitochondrial Membranes/metabolism , Chromatography, Affinity , Ligands
6.
BMC Plant Biol ; 24(1): 266, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38600447

ABSTRACT

BACKGROUND: Mango (Mangifera indica L.) is grown in Hainan, Guangdong, Yunnan, Sichuan, and Fujian provinces and Guanxi autonomous region of China. However, trees growing in these areas suffer severe cold stress during winter, which affects the yield. To this regard, data on global metabolome and transcriptome profiles of leaves are limited. Here, we used combined metabolome and transcriptome analyses of leaves of three mango cultivars with different cold stress tolerance, i.e. Jinhuang (J)-tolerant, Tainung (T) and Guiremang No. 82 (G)-susceptible, after 24 (LF), 48 (MF) and 72 (HF) hours of cold. RESULTS: A total of 1,323 metabolites belonging to 12 compound classes were detected. Of these, amino acids and derivatives, nucleotides and derivatives, and lipids accumulated in higher quantities after cold stress exposure in the three cultivars. Notably, Jinhuang leaves showed increasing accumulation trends of flavonoids, terpenoids, lignans and coumarins, and alkaloids with exposure time. Among the phytohormones, jasmonic acid and abscisic acid levels decreased, while N6-isopentenyladenine increased with cold stress time. Transcriptome analysis led to the identification of 22,526 differentially expressed genes. Many genes enriched in photosynthesis, antenna proteins, flavonoid, terpenoid (di- and sesquiterpenoids) and alkaloid biosynthesis pathways were upregulated in Jihuang leaves. Moreover, expression changes related to phytohormones, MAPK (including calcium and H2O2), and the ICE-CBF-COR signalling cascade indicate involvement of these pathways in cold stress responses. CONCLUSION: Cold stress tolerance in mango leaves is associated with regulation of primary and secondary metabolite biosynthesis pathways. Jasmonic acid, abscisic acid, and cytokinins are potential regulators of cold stress responses in mango leaves.


Subject(s)
Cyclopentanes , Mangifera , Oxylipins , Transcriptome , Cold-Shock Response/genetics , Mangifera/genetics , Plant Growth Regulators/metabolism , Abscisic Acid/metabolism , Hydrogen Peroxide/metabolism , China , Gene Expression Profiling , Gene Expression Regulation, Plant
7.
BMC Plant Biol ; 24(1): 208, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38519933

ABSTRACT

BACKGROUND: Mango (Mangifera indica L.) faces escalating challenges from increasing drought stress due to erratic climate patterns, threatening yields, and quality. Understanding mango's drought response mechanisms is pivotal for resilience and food security. RESULTS: Our RNA-seq analyses unveil 12,752 differentially expressed genes linked to stress signaling, hormone regulation, and osmotic adjustment. Weighted Gene Co-expression Network Analysis identified three essential genes-WRKY transcription factor 3, polyamine oxidase 4, and protein MEI2-like 1-as drought defense components. WRKY3 having a role in stress signaling and defense validates its importance. Polyamine oxidase 4, vital in stress adaptation, enhances drought defense. Protein MEI2-like 1's significance emerges, hinting at novel roles in stress responses. Metabolite profiling illuminated Mango's metabolic responses to drought stress by presenting 990 differentially abundant metabolites, mainly related to amino acids, phenolic acids, and flavonoids, contributing to a deeper understanding of adaptation strategies. The integration between genes and metabolites provided valuable insights by revealing the correlation of WRKY3, polyamine oxidase 4 and MEI2-like 1 with amino acids, D-sphingnosine and 2,5-Dimethyl pyrazine. CONCLUSIONS: This study provides insights into mango's adaptive tactics, guiding future research for fortified crop resilience and sustainable agriculture. Harnessing key genes and metabolites holds promise for innovative strategies enhancing drought tolerance in mango cultivation, contributing to global food security efforts.


Subject(s)
Mangifera , Resilience, Psychological , Droughts , Mangifera/genetics , Gene Expression Profiling , Amino Acids , Stress, Physiological/genetics , Gene Expression Regulation, Plant
8.
Metab Eng ; 81: 182-196, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38103887

ABSTRACT

Anthocyanins are widely distributed pigments in flowering plants with red, purple or blue colours. Their properties in promoting heath make anthocyanins perfect natural colourants for food additives. However, anthocyanins with strong colour and stability at neutral pH, suitable as food colourants are relatively rare in nature. Acylation increases anthocyanin stability and confers bluer colour. In this study, we isolated two anthocyanin regulators SbMyb75 and SbDel from S. baicalensis, and showed that constitutive expression of the two TFs led to accumulation of anthocyanins at high levels in black carrot hairy roots. However, these hairy roots had severe growth problems. We then developed a ß-estradiol inducible system using XVE and a Lex-35S promoter, to initiate expression of the anthocyanin regulators and induced this system in hairy roots of black carrot, tobacco and morning glory. Anthocyanins with various decorations were produced in these hairy roots without any accompanying side-effects on growth. We further produced highly acylated anthocyanins with blue colour in a 5 L liquid culture in a bioreactor of hairy roots from morning glory. We provide here a strategy to produce highly decorated anthocyanins without the need for additional engineering of any of the genes encoding decorating enzymes. This strategy could be transferred to other species, with considerable potential for natural colourant production for the food industries.


Subject(s)
Anthocyanins , Nicotiana , Anthocyanins/genetics , Nicotiana/genetics , Bioreactors , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Roots/genetics
9.
Ann Neurol ; 94(3): 442-456, 2023 09.
Article in English | MEDLINE | ID: mdl-37243334

ABSTRACT

OBJECTIVES: Glymphatic function has not yet been explored in behavioral variant frontotemporal dementia (bvFTD). The spatial correlation between regional glymphatic function and bvFTD remains unknown. METHOD: A total of 74 patients with bvFTD and 67 age- and sex-matched healthy controls (HCs) were selected from discovery dataset and replication dataset. All participants underwent neuropsychological assessment. Glymphatic measures including choroid plexus (CP) volume, diffusion tensor imaging along the perivascular (DTI-ALPS) index, and coupling between blood-oxygen-level-dependent signals and cerebrospinal fluid signals (BOLD-CSF coupling), were compared between the two groups. Regional glymphatic function was evaluated by dividing DTI-ALPS and BOLD-CSF coupling into anterior, middle, and posterior regions. The bvFTD-related metabolic pattern was identified using spatial covariance analysis based on l8 F-FDG-PET. RESULTS: Patients with bvFTD showed higher CP volume (p < 0.001); anterior and middle DTI-ALPS (p < 0.001); and weaker anterior BOLD-CSF coupling (p < 0.05) than HCs after controlling for cortical gray matter volume in both datasets. In bvFTD from the discovery dataset, the anterior DTI-ALPS was negatively associated with the expression of the bvFTD-related metabolic pattern (r = -0.52, p = 0.034) and positively related with regional standardized uptake value ratios of l8 F-FDG-PET in bvFTD-related brain regions (r range: 0.49 to 0.62, p range: 0.017 to 0.047). Anterior and middle glymphatic functions were related to global cognition and disease severity. INTERPRETATION: Our findings reveal abnormal glymphatic function, especially in the anterior and middle regions of brain in bvFTD. Regional glymphatic dysfunction may contribute to the pathogenesis of bvFTD. ANN NEUROL 2023;94:442-456.


Subject(s)
Frontotemporal Dementia , Humans , Frontotemporal Dementia/pathology , Diffusion Tensor Imaging/methods , Fluorodeoxyglucose F18 , Brain/pathology , Gray Matter/pathology
10.
Acta Pharmacol Sin ; 45(3): 609-618, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38030799

ABSTRACT

Leveraging the specificity of antibody to deliver cytotoxic agent into tumor, antibody-drug conjugates (ADCs) have become one of the hotspots in the development of anticancer therapies. Although significant progress has been achieved, there remain challenges to overcome, including limited penetration into solid tumors and potential immunogenicity. Fully human single-domain antibodies (UdAbs), with their small size and human nature, represent a promising approach for addressing these challenges. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) is a glycosylated cell surface protein that rarely expressed in normal adult tissues but overexpressed in diverse cancers, taking part in tumorigenesis, progression, and metastasis. In this study, we investigated the therapeutic potential of UdADC targeting CEACAM5. We performed biopanning in our library and obtained an antibody candidate B9, which bound potently and specifically to CEACAM5 protein (KD = 4.84 nM) and possessed excellent biophysical properties (low aggregation tendency, high homogeneity, and thermal stability). The conjugation of B9 with a potent cytotoxic agent, monomethyl auristatin E (MMAE), exhibited superior antitumor efficacy against CEACAM5-expressing human gastric cancer cell line MKN-45, human pancreatic carcinoma cell line BxPC-3 and human colorectal cancer cell line LS174T with IC50 values of 38.14, 25.60, and 101.4 nM, respectively. In BxPC-3 and MKN-45 xenograft mice, administration of UdADC B9-MMAE (5 mg/kg, i.v.) every 2 days for 4 times markedly inhibited the tumor growth without significant change in body weight. This study may have significant implications for the design of next-generation ADCs.


Subject(s)
Antineoplastic Agents , Immunoconjugates , Single-Domain Antibodies , Humans , Animals , Mice , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Immunoconjugates/pharmacology , Immunoconjugates/therapeutic use , Cell Adhesion Molecules , Cytotoxins , Xenograft Model Antitumor Assays , Carcinoembryonic Antigen , GPI-Linked Proteins
11.
Neurol Sci ; 45(2): 557-564, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37668827

ABSTRACT

BACKGROUND: The mild behavioral impairment checklist (MBI-C) designed to capture neuropsychiatric symptoms in the whole spectrum of elder with or without dementia, have been verified in mild behavioral impairment, mild cognitive impairment and Alzheimer's Disease, but never used in the behavioral variant of frontotemporal dementia (bvFTD). METHODS: Fifty-two patients with bvFTD (mild, n = 30; moderate-severe, n = 22) and 82 community-dwelling elderly individuals (HCs) were enrolled. All subjects were assessed with a full neuropsychological scale including the MBI-C, Neuropsychiatric Inventory Questionnaire (NPI-Q), and Frontal Behavioral Inventory (FBI). Receiver operating characteristic curves were drawn to analyze the sensitivity and specificity of the MBI-C, NPI-Q, and FBI, and cutoff points were determined using the Youden index. RESULTS: The MBI-C and domain scores in all patients with bvFTD were significantly higher than those in HCs. The most common symptoms of bvFTD were apathy (82.7%) and impulse dyscontrol (80.8%). The MBI-C score was positively correlated with the NPI-Q, FBI, and Activities of Daily Living. For differentiating patients with both bvFTD and mild bvFTD from HCs, the optimal MBI-C cutoff point was 5.5 with a sensitivity of 100% and specificity of 82%, and its sensitivity was higher than that of the NPI-Q and FBI. CONCLUSION: The MBI-C is a sensitive tool for screening behavioral and psychological symptoms in patients with bvFTD, even in the early stages of the disease.


Subject(s)
Cognitive Dysfunction , Frontotemporal Dementia , Humans , Aged , Frontotemporal Dementia/diagnosis , Checklist , Activities of Daily Living , Neuropsychological Tests , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/psychology , China
12.
Neurol Sci ; 45(8): 3573-3582, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38772979

ABSTRACT

INTRODUCTION: Identifying coronavirus disease 2019 (COVID-19)-related encephalitis without clear etiological evidence is clinically challenging. The distinctions between this condition and other prevalent encephalitis types remain unknown. Therefore, we aimed to explore the similarities and differences in the clinical characteristics of COVID-19-related encephalitis and other encephalitis types. METHODS: Adult patients with encephalitis admitted to the neurology department at Xuanwu Hospital were enrolled and categorized into the following six groups based on the results of metagenomic next-generation sequencing and autoimmune antibody detection in cerebrospinal fluid (CSF): COVID-19-related encephalitis (n = 36), herpes simplex virus type 1 encephalitis (HSV-1 encephalitis; n = 28), human herpesvirus 3 encephalitis (HHV-3 encephalitis; n = 10), NMDAR-antibody encephalitis (n = 18), LGI1-antibody encephalitis (n = 12), and GABAB-antibody encephalitis (n = 8). RESULTS: The predominant characteristics of COVID-19-related encephalitis include a low incidence of seizures (38.9%), cognitive defects (30.6%), and meningeal irritation signs (8.3%). Compared with HSV-1 and HHV-3 encephalitis, COVID-19-related encephalitis exhibited lower white blood cell count (2.5 count/mm3), protein (32.2 mg/dL), and immunoglobulin M, G, and A levels (0.09, 3.2, and 0.46 mg/dL, respectively) in the CSF tests. Abnormal imaging findings were present in only 36.1% of COVID-19-related encephalitis cases, mostly showing diffuse inflammation scattered in various parts, which differed from HSV-1 encephalitis. Additionally, COVID-19-related encephalitis exhibited significant differences in clinical symptoms and CSF white blood cell counts compared with NMDAR-antibody encephalitis; however, it showed limited differences compared with LGI1-antibody and GABAB-antibody encephalitis. DISCUSSION: COVID-19-related encephalitis and herpes virus or autoimmune encephalitis differ clinically. Symptoms and auxiliary examinations can be used as distinguishing tools.


Subject(s)
COVID-19 , Encephalitis, Herpes Simplex , Encephalitis , Hashimoto Disease , Humans , COVID-19/complications , Female , Male , Middle Aged , Adult , Encephalitis/diagnosis , Encephalitis/cerebrospinal fluid , Encephalitis, Herpes Simplex/cerebrospinal fluid , Encephalitis, Herpes Simplex/diagnosis , Encephalitis, Herpes Simplex/complications , Hashimoto Disease/cerebrospinal fluid , Hashimoto Disease/diagnosis , Aged , Autoantibodies/cerebrospinal fluid , Autoantibodies/blood , Encephalitis, Viral/diagnosis , Encephalitis, Viral/cerebrospinal fluid , SARS-CoV-2 , Anti-N-Methyl-D-Aspartate Receptor Encephalitis/diagnosis , Anti-N-Methyl-D-Aspartate Receptor Encephalitis/cerebrospinal fluid
13.
J Environ Manage ; 350: 119623, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38029496

ABSTRACT

The hydrolysis of extracellular polymeric substances (EPS) represents a critical bottleneck in the anaerobic fermentation of waste activated sludge (WAS), while tryptophan is identified as an underestimated constituent of EPS. Herein, we harnessed a tryptophan-degrading microbial consortium (TDC) to enhance the hydrolysis efficiency of WAS. At TDC dosages of 5%, 10%, and 20%, a notable increase in SCOD was observed by factors of 1.13, 1.39, and 1.88, respectively. The introduction of TDC improved both the yield and quality of short chain fatty acids (SCFAs), the maximum SCFA yield increased from 590.6 to 1820.2, 1957.9 and 2194.9 mg COD/L, whilst the acetate ratio within SCFAs was raised from 34.1% to 61.2-70.9%. Furthermore, as TDC dosage increased, the relative activity of protease exhibited significant increments, reaching 116.3%, 168.0%, and 266.1%, respectively. This enhancement facilitated WAS solubilization and the release of organic substances from bound EPS into soluble EPS. Microbial analysis identified Tetrasphaera and Soehngenia as key participants in WAS solubilization and the breakdown of protein fraction. Metabolic analysis revealed that TDC triggered the secretion of enzymes associated with amino acid metabolism and fatty acid biosynthesis, thereby fostering the decomposition of proteins and production of SCFAs.


Subject(s)
Sewage , Tryptophan , Humans , Fermentation , Sewage/chemistry , Anaerobiosis , Tryptophan/metabolism , Fatty Acids, Volatile/metabolism , Hydrogen-Ion Concentration
14.
Angew Chem Int Ed Engl ; : e202406946, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802316

ABSTRACT

Control of phosphate capture and release is vital in environmental, biological, and pharmaceutical contexts. However, the binding of trivalent phosphate (PO4 3-) in water is exceptionally difficult due to its high hydration energy. Based on the anion coordination chemistry of phosphate, in this study, four charge-neutral tripodal hexaurea receptors (L1-L4), which were equipped with morpholine and polyethylene glycol terminal groups to enhance their solubility in water, were synthesized to enable the pH-triggered phosphate binding and release in aqueous solutions. Encouragingly, the receptors were found to bind PO4 3- anion in a 1 : 1 ratio via hydrogen bonds in 100 % water solutions, with L1 exhibiting the highest binding constant (1.2×103 M-1). These represent the first neutral anion ligands to bind phosphate in 100 % water and demonstrate the potential for phosphate capture and release in water through pH-triggered mechanisms, mimicking native phosphate binding proteins. Furthermore, L1 can also bind multiple bioavailable phosphate species, which may serve as model systems for probing and modulating phosphate homeostasis in biological and biomedical researches.

15.
Plant Physiol ; 188(3): 1496-1506, 2022 03 04.
Article in English | MEDLINE | ID: mdl-34893909

ABSTRACT

Tanshinone ⅡA (TⅡA), a diterpene quinone with a furan ring, is a bioactive compound found in the medicinal herb redroot sage (Salvia miltiorrhiza Bunge), in which both furan and dihydrofuran analogs are present in abundance. Progress has been made recently in elucidating the tanshinone biosynthetic pathway, including heterocyclization of the dihydrofuran D-ring by cytochrome P450s; however, dehydrogenation of dihydrofuran to furan, a key step of furan ring formation, remains uncharacterized. Here, by differential transcriptome mining, we identified six 2-oxoglutarate-dependent dioxygenase (2-ODD) genes whose expressions corresponded to tanshinone biosynthesis. We showed that Sm2-ODD14 acts as a dehydrogenase catalyzing the furan ring aromatization. In vitro Sm2-ODD14 converted cryptotanshinone to TⅡA and thus was designated TⅡA synthase (SmTⅡAS). Furthermore, SmTⅡAS showed a strict substrate specificity, and repression of SmTⅡAS expression in hairy root by RNAi led to increased accumulation of total dihydrofuran-tanshinones and decreased production of furan-tanshinones. We conclude that SmTⅡAS controls the metabolite flux from dihydrofuran- to furan-tanshinones, which influences medicinal properties of S. miltiorrhiza.


Subject(s)
Dioxygenases/genetics , Dioxygenases/metabolism , Diterpenes/metabolism , Furans/metabolism , Plants, Medicinal/metabolism , Salvia miltiorrhiza/genetics , Salvia miltiorrhiza/metabolism , Biosynthetic Pathways , Gene Expression Regulation, Plant , Genes, Plant , Plant Roots/metabolism
16.
J Magn Reson Imaging ; 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38014782

ABSTRACT

Among the approximately 20 million patients with drug-resistant epilepsy (DRE) worldwide, the vast majority can benefit from surgery to minimize seizure reduction and neurological impairment. Precise preoperative localization of epileptogenic zone (EZ) and complete resection of the lesions can influence the postoperative prognosis. However, precise localization of EZ is difficult, and the structural and functional alterations in the brain caused by DRE vary by etiology. Neuroimaging has emerged as an approach to identify the seizure-inducing structural and functional changes in the brain, and magnetic resonance imaging (MRI) and positron emission tomography (PET) have become routine noninvasive imaging tools for preoperative evaluation of DRE in many epilepsy treatment centers. Multimodal neuroimaging offers unique advantages in detecting EZ, especially in improving the detection rate of patients with negative MRI or PET findings. This approach can characterize the brain imaging characteristics of patients with DRE caused by different etiologies, serving as a bridge between clinical and pathological findings and providing a basis for individualized clinical treatment plans. In addition to the integration of multimodal imaging modalities and the development of special scanning sequences and image post-processing techniques for early and precise localization of EZ, the application of deep machine learning for extracting image features and deep learning-based artificial intelligence have gradually improved diagnostic efficiency and accuracy. These improvements can provide clinical assistance for precisely outlining the scope of EZ and indicating the relationship between EZ and functional brain areas, thereby enabling standardized and precise surgery and ensuring good prognosis. However, most existing studies have limitations imposed by factors such as their small sample sizes or hypothesis-based study designs. Therefore, we believe that the application of neuroimaging and post-processing techniques in DRE requires further development and that more efficient and accurate imaging techniques are urgently needed in clinical practice. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.

17.
Circ Res ; 128(1): 8-23, 2021 01 08.
Article in English | MEDLINE | ID: mdl-33092471

ABSTRACT

RATIONALE: Thoracic aortic aneurysm (TAA) leads to substantial mortality worldwide. Familial and syndromic TAAs are highly correlated with genetics. However, the incidence of sporadic isolated TAA (iTAA) is much higher, and the genetic contribution is not yet clear. OBJECTIVE: Here, we examined the genetic characteristics of sporadic iTAA. METHODS AND RESULTS: We performed a genetic screen of 551 sporadic iTAA cases and 1071 controls via whole-exome sequencing. The prevalence of pathogenic mutations in known causal genes was 5.08% in the iTAA cohort. We selected 100 novel candidate genes using a strict strategy, and the suspected functional variants of these genes were significantly enriched in cases compared with controls and carried by 60.43% of patients. We found more severe phenotypes and a lower proportion of hypertension in cases with pathogenic mutations or suspected functional variants. Among the candidate genes, Testin (TES), which encodes a focal adhesion scaffold protein, was identified as a potential TAA causal gene, accounting for 4 patients with 2 missense variants in the LIM1 domain (c.751T>C encoding p.Y251H; c.838T>C encoding p.Y280H) and highly expressed in the aorta. The 2 variants led to a decrease in TES expression. The thoracic aorta was spontaneously dilated in the TesY249H knock-in and Tes-/- mice. Mechanistically, the p.Y249H variant or knockdown of TES led to the repression of vascular smooth muscle cell contraction genes and disturbed the vascular smooth muscle cell contractile phenotype. Interestingly, suspected functional variants of other focal adhesion scaffold genes, including TLN1 (Talin-1) and ZYX (zyxin), were also significantly enriched in patients with iTAA; moreover, their knockdown resulted in decreased contractility of vascular smooth muscle cells. CONCLUSIONS: For the first time, this study revealed the genetic landscape across iTAA and showed that the focal adhesion scaffold genes are critical in the pathogenesis of iTAA.


Subject(s)
Aortic Aneurysm, Thoracic/genetics , Aortic Dissection/genetics , Cytoskeletal Proteins/genetics , Focal Adhesions/genetics , Mutation, Missense , Polymorphism, Single Nucleotide , RNA-Binding Proteins/genetics , Adult , Aortic Dissection/diagnostic imaging , Aortic Dissection/metabolism , Aortic Dissection/physiopathology , Animals , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/metabolism , Aorta, Thoracic/physiopathology , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Aneurysm, Thoracic/metabolism , Aortic Aneurysm, Thoracic/physiopathology , Case-Control Studies , Cells, Cultured , Cytoskeletal Proteins/metabolism , Female , Focal Adhesions/metabolism , Genetic Predisposition to Disease , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Muscle, Smooth, Vascular/diagnostic imaging , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/physiopathology , Phenotype , RNA-Binding Proteins/metabolism , Talin/genetics , Talin/metabolism , Vasoconstriction , Exome Sequencing , Zyxin/genetics , Zyxin/metabolism
18.
Eur J Neurol ; 30(4): 813-822, 2023 04.
Article in English | MEDLINE | ID: mdl-36617541

ABSTRACT

BACKGROUND AND PURPOSE: This study was undertaken to elucidate the clinical profile of sporadic fatal insomnia (sFI), assess the similarities and differences between sFI and fatal familial insomnia (FFI), and evaluate the influence of ethnicity on the phenotype of sFI patients. METHODS: The data of sFI and FFI patients were retrieved from our case series and through literature review. The clinical and diagnostic features of sFI and FFI were compared, as were the phenotypes of Asian and Caucasian sFI patients. RESULTS: We identified 44 sFI and 157 FFI cases. The prevalence of sleep-related, neuropsychiatric, and autonomic symptoms among the sFI patients were 65.9%, 100.0%, and 43.2%, respectively. Compared to FFI, sFI exhibited longer disease duration and a higher proportion of neuropsychiatric symptoms, whereas FFI was characterized by a higher incidence of sleep-related and autonomic symptoms in the early stages of the disease or throughout its course. In addition, a higher proportion of the sFI patients showed hyperintensity on magnetic resonance imaging (MRI) and periodic sharp wave complexes on electroencephalography compared to the FFI patients, especially those presenting with pathological changes associated with MM2-cortical type sporadic Creutzfeldt-Jakob disease. The Asian sFI patients had a higher proportion of males and positivity for cerebrospinal fluid 14-3-3 protein, and fewer sleep-related symptoms compared to Caucasian sFI patients. The age at onset and duration of sFI differed between ethnic groups, but the difference failed to reach statistical significance. CONCLUSIONS: Despite its similarities to FFI, sFI is characterized by longer disease duration, higher proportion of neuropsychiatric symptoms, and hyperintensity on MRI, along with differences in the clinical characteristics based on ethnicity.


Subject(s)
Creutzfeldt-Jakob Syndrome , Insomnia, Fatal Familial , Sleep Initiation and Maintenance Disorders , Male , Humans , Sleep Initiation and Maintenance Disorders/pathology , Creutzfeldt-Jakob Syndrome/diagnosis , Insomnia, Fatal Familial/diagnosis , Insomnia, Fatal Familial/genetics , Insomnia, Fatal Familial/pathology , Sleep , Magnetic Resonance Imaging , Brain/pathology
19.
BMC Neurol ; 23(1): 34, 2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36690949

ABSTRACT

INTRODUCTION: Creutzfeldt-Jakob disease (CJD) is a fatal and irreversible neurodegenerative disease. Identification of inexpensive and easy-to-implement biomarkers of CJD which could predict disease severity and patient survival is important for improving disease management. The aim of this study was to assess the predictive value of peripheral neutrophil to lymphocyte ratio (NLR), high-density lipoprotein (HDL), monocyte to HDL ratio (MHR) and neutrophil to HDL ratio (NHR) for CJD. METHODS: Patients with definite or probable CJD admitted to the Neurology Department of Xuanwu Hospital from 2014 to 2021 were enrolled and followed up until April 2022. Clinical information including sex, age, Barth Index, survival time and results of auxiliary examination were collected, and NLR, HDL, NHR and MHR were measured for all enrolled patients. The associations between NLR, HDL, NHR and MHR, and disease severity (evaluated by Barth Index), survival time and auxiliary examinations were evaluated. RESULTS: A total of 88 CJD patients were enrolled and all were deceased. NLR (r = -0.341, p = 0.001), NHR (r = -0.346, p = 0.001) and MHR (r = -0.327, p = 0.002) were significantly associated with disease severity. Higher NHR (HR = 2.344, 95% CI = 1.277-4.303 p = 0.006) and lower HDL (HR = 0.567, 95% CI = 0.346-0.930, p = 0.025) were associated with shorter survival time in the CJD patients. CONCLUSIONS: Peripheral inflammatory biomarkers, especially NHR, were associated with disease severity and survival duration. These findings provide new insights into the mechanisms and treatment strategies of CJD.


Subject(s)
Creutzfeldt-Jakob Syndrome , Neurodegenerative Diseases , Humans , Lipoproteins, HDL , Creutzfeldt-Jakob Syndrome/diagnosis , Neutrophils , Biomarkers , Patient Acuity , Cholesterol, HDL , Retrospective Studies
20.
Mol Ther ; 30(8): 2785-2799, 2022 08 03.
Article in English | MEDLINE | ID: mdl-35462042

ABSTRACT

The inefficient tumor penetration of therapeutic antibodies has hampered their effective use in treating solid tumors. Here, we report the identification of a fully human single-domain antibody (UdAb), designated as n501, targeting the oncofetal antigen 5T4. The high-resolution crystal structure indicates that n501 adopts a compact structure very similar to that of camelid nanobodies, and binds tightly to all eight leucine-rich repeats of 5T4. Furthermore, the UdAb n501 exhibits exceptionally high stability, with no apparent activity changes over 4 weeks of storage at various temperatures. Importantly, the UdAb-based antibody-drug conjugate (n501-SN38) showed much deeper tumor penetration, significantly higher tumor uptake, and faster accumulation at tumor sites than conventional IgG1-based antibody-drug conjugate (m603-SN38), resulting in improved tumor inhibition. These results highlight the potential of UdAb-based antibody-drug conjugates as a potential class of antitumor therapeutics with characteristics of high stability and strong tumor penetration for the effective treatment of solid tumors.


Subject(s)
Antineoplastic Agents , Immunoconjugates , Single-Domain Antibodies , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Humans , Immunoconjugates/pharmacology , Immunoconjugates/therapeutic use , Single-Domain Antibodies/pharmacology , Single-Domain Antibodies/therapeutic use
SELECTION OF CITATIONS
SEARCH DETAIL