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1.
Plant Cell ; 35(6): 1671-1707, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-36747354

RESUMO

RNA can fold back on itself to adopt a wide range of structures. These range from relatively simple hairpins to intricate 3D folds and can be accompanied by regulatory interactions with both metabolites and macromolecules. The last 50 yr have witnessed elucidation of an astonishing array of RNA structures including transfer RNAs, ribozymes, riboswitches, the ribosome, the spliceosome, and most recently entire RNA structuromes. These advances in RNA structural biology have deepened insight into fundamental biological processes including gene editing, transcription, translation, and structure-based detection and response to temperature and other environmental signals. These discoveries reveal that RNA can be relatively static, like a rock; that it can have catalytic functions of cutting bonds, like scissors; and that it can adopt myriad functional shapes, like paper. We relate these extraordinary discoveries in the biology of RNA structure to the plant way of life. We trace plant-specific discovery of ribozymes and riboswitches, alternative splicing, organellar ribosomes, thermometers, whole-transcriptome structuromes and pan-structuromes, and conclude that plants have a special set of RNA structures that confer unique types of gene regulation. We finish with a consideration of future directions for the RNA structure-function field.


Assuntos
RNA Catalítico , Riboswitch , RNA/genética , RNA Catalítico/genética , RNA Catalítico/química , Transcriptoma , Processamento Alternativo
2.
Plant Physiol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753307

RESUMO

Sweet osmanthus (Osmanthus fragrans) is famous in China for its flowers and contains four groups: Albus, Luteus, Aurantiacus, and Asiaticus. Understanding the relationships among these groups and the genetic mechanisms of flower color and aroma biosynthesis are of tremendous interest. In this study, we sequenced representative varieties from two of the four sweet osmanthus groups. Multi-omic and phylogenetic analyses of varieties from each of the four groups showed that Asiaticus split first within the species, followed by Aurantiacus and the sister groups Albus and Luteus. We show that the difference in flower color between Aurantiacus and the other three groups was caused by a 4-bp deletion in the promoter region of carotenoid cleavage dioxygenase 4 (OfCCD4) that leads to expression decrease. In addition, we identified 44 gene pairs exhibiting significant structural differences between the multi-seasonal flowering variety 'Rixianggui' in the Asiaticus group and other autumn flowering varieties. Through correlation analysis between intermediate products of aromatic components and gene expression, we identified eight genes associated with the linalool, α- and ß-ionone biosynthesis pathways. Overall, our study offers valuable genetic resources for sweet osmanthus, while also providing genetic clues for improving the flower color and multi-season flowering of osmanthus and other flowers.

3.
Exp Cell Res ; 436(2): 113974, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346630

RESUMO

The extracellular matrix (ECM) mechanical properties regulate biological processes, such as fibroblast-myofibroblast transformation (FMT), which is a crucial component in pelvic organ prolapse (POP) development. The 'Kindlin-2' protein, expressed by fibroblasts, plays an important role in the development of the mesoderm, which is responsible for connective tissue formation; however, the role of Kindlin-2 in FMT remains to be explored. In this study, we aimed to explore the role of Kindlin-2 in FMT as it relates to POP. We found that ECM stiffness induces autophagy to translocate Kindlin-2 to the cytoplasm of L929 cells, where it interacts with and degrades MOB1, thereby facilitating Yes-associated protein (YAP) entry into the nucleus and influencing FMT progression. Stiffness-induced autophagy was inhibited when using an autophagy inhibitor, which blocked the translocation of Kindlin-2 to the cytoplasm and partially reversed high-stiffness-induced FMT. In patients with POP, we observed an increase in cytoplasmic Kindlin-2 and nuclear YAP levels. Similar changes in vaginal wall-associated proteins were observed in a mouse model of acute vaginal injury. In conclusion, Kindlin-2 is a key gene affecting ECM stiffness, which regulates FMT by inducing autophagy and may influence the development of POP.


Assuntos
Proteínas do Citoesqueleto , Matriz Extracelular , Proteínas Musculares , Miofibroblastos , Animais , Feminino , Humanos , Camundongos , Citoplasma/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Miofibroblastos/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas Musculares/metabolismo
5.
Cell Mol Life Sci ; 81(1): 57, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279052

RESUMO

The Wnt/ß-catenin pathway is critical to maintaining cell fate decisions. Recent study showed that liquid-liquid-phase separation (LLPS) of Axin organized the ß-catenin destruction complex condensates in a normal cellular state. Mutations inactivating the APC gene are found in approximately 80% of all human colorectal cancer (CRC). However, the molecular mechanism of the formation of ß-catenin destruction complex condensates organized by Axin phase separation and how APC mutations impact the condensates are still unclear. Here, we report that the ß-catenin destruction complex, which is constructed by Axin, was assembled condensates via a phase separation process in CRC cells. The key role of wild-type APC is to stabilize destruction complex condensates. Surprisingly, truncated APC did not affect the formation of condensates, and GSK 3ß and CK1α were unsuccessfully recruited, preventing ß-catenin phosphorylation and resulting in accumulation in the cytoplasm of CRCs. Besides, we propose that the phase separation ability of Axin participates in the nucleus translocation of ß-catenin and be incorporated and concentrated into transcriptional condensates, affecting the transcriptional activity of Wnt signaling pathway.


Assuntos
Complexo de Sinalização da Axina , beta Catenina , Humanos , Complexo de Sinalização da Axina/genética , Proteína Axina/genética , Proteína Axina/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Separação de Fases , Mutação/genética , Via de Sinalização Wnt/genética , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo
6.
Nucleic Acids Res ; 51(2): 619-630, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36546827

RESUMO

Jasmonic acid (JA) signaling plays a pivotal role in plant development and defense. MYC2 is a master transcription factor in JA signaling, and was found to be phosphorylated and negatively regulated by MAP kinase and receptor-like kinase. However, the kinases that positively regulate MYC2 through phosphorylation and promote MYC2-mediated activation of JA response have not been identified. Here, we identified CK2 as a kinase that phosphorylates MYC2 and thus regulates the JA signaling. CK2 holoenzyme can interact with MYC2 using its regulatory subunits and phosphorylate MYC2 at multiple sites with its catalytic subunits. Inhibition of CK2 activity in a dominant-negative plant line, CK2mut, repressed JA response. On the other hand, increasing CK2 activity by overexpression of CKB4, a regulatory subunit gene of CK2, enhanced JA response in a MYC2-dependent manner. Substitution of the Ser and Thr residues at phosphorylation sites of MYC2 by CK2 with Ala impaired MYC2 function in activating JA response. Further investigations evidenced that CK2 facilitated the JA-induced increase of MYC2 binding to the promoters of JA-responsive genes in vivo. Our study demonstrated that CK2 plays a positive role in JA signaling, and reveals a previously undiscovered mechanism that regulates MYC2 function.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Caseína Quinase II , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfotransferases/genética , Caseína Quinase II/metabolismo
7.
J Neurosci ; 43(17): 3009-3027, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36898834

RESUMO

RNA N4-acetylcytidine (ac4C) modification is increasingly recognized as an important layer of gene regulation; however, the involvement of ac4C in pain regulation has not been studied. Here, we report that N-acetyltransferase 10 protein (NAT10; the only known ac4C "writer") contributes to the induction and development of neuropathic pain in an ac4C-dependent manner. Peripheral nerve injury increases the levels of NAT10 expression and overall ac4C in injured dorsal root ganglia (DRGs). This upregulation is triggered by the activation of upstream transcription factor 1 (USF1), a transcription factor that binds to the Nat10 promoter. Knock-down or genetic deletion of NAT10 in the DRG abolishes the gain of ac4C sites in Syt9 mRNA and the augmentation of SYT9 protein, resulting in a marked antinociceptive effect in nerve-injured male mice. Conversely, mimicking NAT10 upregulation in the absence of injury evokes the elevation of Syt9 ac4C and SYT9 protein and induces the genesis of neuropathic-pain-like behaviors. These findings demonstrate that USF1-governed NAT10 regulates neuropathic pain by targeting Syt9 ac4C in peripheral nociceptive sensory neurons. Our findings establish NAT10 as a critical endogenous initiator of nociceptive behavior and a promising new target for treating neuropathic pain.SIGNIFICANCE STATEMENT The cytidine N4-acetylcytidine (ac4C), a new epigenetic RNA modification, is crucial for the translation and stability of mRNA, but its role for chronic pain remains unclear. Here, we demonstrate that N-acetyltransferase 10 (NAT10) acts as ac4C N-acetyltransferase and plays an important role in the development and maintenance of neuropathic pain. NAT10 was upregulated via the activation of the transcription factor upstream transcription factor 1 (USF1) in the injured dorsal root ganglion (DRG) after peripheral nerve injury. Since pharmacological or genetic deleting NAT10 in the DRG attenuated the nerve injury-induced nociceptive hypersensitivities partially through suppressing Syt9 mRNA ac4C and stabilizing SYT9 protein level, NAT10 may serve as an effective and novel therapeutic target for neuropathic pain.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Masculino , Camundongos , Acetiltransferases/metabolismo , Citidina/farmacologia , Citidina/genética , Citidina/metabolismo , Gânglios Espinais/metabolismo , Neuralgia/etiologia , Neuralgia/metabolismo , Traumatismos dos Nervos Periféricos/complicações , Traumatismos dos Nervos Periféricos/metabolismo , RNA , RNA Mensageiro/metabolismo , Células Receptoras Sensoriais/metabolismo , Fatores de Transcrição/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38501173

RESUMO

We have reported previously that during hypoxia exposure, the expression of mature miR-17~92 was first upregulated and then downregulated in pulmonary artery smooth muscle cells (PASMC) and in mouse lungs in vitro and in vivo. Here we investigated the mechanisms regulating this bi-phasic expression of miR-17~92 in PASMC in hypoxia. We measured the level of primary miR-17~92 in PASMC during hypoxia exposure and found that short-term hypoxia exposure (3%O2, 6 hours) induced the level of primary miR-17~92, while long-term hypoxia exposure (3%O2, 24 hours) decreased its level, suggesting a bi-phasic regulation of miR-17~92 expression at the transcriptional level. We found that short-term hypoxia-induced upregulation of miR-17~92 was HIF1α and E2F1 dependent. Two HIF1α binding sites on miR-17~92 promoter were identified. We also found that long-term hypoxia-induced suppression of miR-17~92 expression could be restored by silencing of p53. Mutation of the p53-binding sites in the miR-17~92 promoter increased miR-17~92 promoter activity in both normoxia and hypoxia. Our findings suggest that the bi-phasic transcriptional regulation of miR-17~92 during hypoxia is controlled by HIF1/E2F1 and p53 in PASMC: during short-term hypoxia exposure, stabilization of HIF1 and induction of E2F1 induces the transcription of miR-17~92; while during long-term hypoxia exposure, hyperphosphorylation of p53 suppresses the expression of miR-17~92.

9.
Clin Immunol ; 258: 109857, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043757

RESUMO

Systemic lupus erythematosus (SLE) is a typical systemic autoimmune disease that manifests as skin rash, arthritis, lymphadenopathy, and multiple organ lesions. Epigenetics, including DNA methylation, histone modification, and non-coding RNA regulation, mainly affect the function and characteristics of cells through the regulation of gene transcription or translation. Increasing evidence indicates that there are a variety of complex epigenetic effects in patients with SLE, which interfere with the differentiation and function of T, and B lymphocytes, monocytes, and neutrophils, and enhance the expression of SLE-associated pathogenic genes. This paper summarizes our currently knowledge regarding pathogenesis of SLE, and introduces current advances in the epigenetic regulation of SLE from three aspects: immune function, inflammatory response, and lupus complications. We propose that epigenetic changes could be used as potential biomarkers and therapeutic targets of SLE.


Assuntos
Artrite , Lúpus Eritematoso Sistêmico , Humanos , Epigênese Genética , Metilação de DNA , Artrite/genética , Diferenciação Celular
10.
Funct Integr Genomics ; 24(3): 114, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38862667

RESUMO

With advances in radioactive particle implantation in clinical practice, Iodine-125 (125I) seed brachytherapy has emerged as a promising treatment for cholangiocarcinoma (CCA), showing good prognosis; however, the underlying molecular mechanism of the therapeutic effect of 125I seed is unclear. To study the effects of 125I seed on the proliferation and apoptosis of CCA cells. CCA cell lines, RBE and HCCC-9810, were treated with reactive oxygen species (ROS) scavenger acetylcysteine (NAC) or the p53 functional inhibitor, pifithrin-α hydrobromide (PFTα). Cell counting kit-8 (CCK-8) assay, 5-bromo-2-deoxy-uridine (BrdU) staining, and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay and flow cytometry assay were performed to test the radiation-sensitivity of 125I seed toward CCA cells at different radiation doses (0.4 mCi and 0.8 mCi). 2,7-dichlorofluorescein diacetate (DCF-DA) assay, real-time quantitative polymerase chain reaction (RT-qPCR), and western blot analysis were performed to assess the effect of 125I seed on the ROS/p53 axis. A dose-dependent inhibitory effect of 125I seeds on the proliferation of CCA cells was observed. The 125I seed promoted apoptosis of CCA cells and induced the activation of the ROS/p53 pathway in a dose-dependent manner. NAC or PFTα treatment effectively reversed the stimulatory effect of 125I seed on the proliferation of CCA cells. NAC or PFTα suppressed apoptosis and p53 protein expression induced by the 125I seed. 125I seed can inhibit cell growth mainly through the apoptotic pathway. The mechanism may involve the activation of p53 and its downstream apoptotic pathway by up-regulating the level of ROS in cells.


Assuntos
Apoptose , Proliferação de Células , Colangiocarcinoma , Radioisótopos do Iodo , Espécies Reativas de Oxigênio , Proteína Supressora de Tumor p53 , Colangiocarcinoma/metabolismo , Colangiocarcinoma/radioterapia , Colangiocarcinoma/patologia , Colangiocarcinoma/genética , Colangiocarcinoma/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Linhagem Celular Tumoral , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/radioterapia , Acetilcisteína/farmacologia , Benzotiazóis/farmacologia , Transdução de Sinais/efeitos dos fármacos
11.
RNA ; 28(1): 16-26, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34706977

RESUMO

RNA interactions are exceptionally strong and highly redundant. As such, nearly any two RNAs have the potential to interact with one another over relatively short stretches, especially at high RNA concentrations. This is especially true for pairs of RNAs that do not form strong self-structure. Such phenomena can drive liquid-liquid phase separation, either solely from RNA-RNA interactions in the presence of divalent or organic cations, or in concert with proteins. RNA interactions can drive multimerization of RNA strands via both base-pairing and tertiary interactions. In this article, we explore the tendency of RNA to form stable monomers, dimers, and higher order structures as a function of RNA length and sequence through a focus on the intrinsic thermodynamic, kinetic, and structural properties of RNA. The principles we discuss are independent of any specific type of biomolecular condensate, and thus widely applicable. We also speculate how external conditions experienced by living organisms can influence the formation of nonmembranous compartments, again focusing on the physical and structural properties of RNA. Plants, in particular, are subject to diverse abiotic stresses including extreme temperatures, drought, and salinity. These stresses and the cellular responses to them, including changes in the concentrations of small molecules such as polyamines, salts, and compatible solutes, have the potential to regulate condensate formation by melting or strengthening base-pairing. Reversible condensate formation, perhaps including regulation by circadian rhythms, could impact biological processes in plants, and other organisms.


Assuntos
Adaptação Fisiológica , Condensados Biomoleculares/química , Células Vegetais/metabolismo , RNA/química , Pareamento de Bases , Sequência de Bases , Condensados Biomoleculares/metabolismo , Ligação de Hidrogênio , Cinética , Conformação de Ácido Nucleico , Plantas/metabolismo , Poliaminas/química , Poliaminas/metabolismo , Polimerização , RNA/metabolismo , Sais/química , Sais/metabolismo , Estresse Fisiológico , Termodinâmica
12.
J Exp Bot ; 75(7): 1903-1918, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37856192

RESUMO

The plant cuticle is an important protective barrier on the plant surface, constructed mainly by polymerized cutin matrix and a complex wax mixture. Although the pathway of plant cuticle biosynthesis has been clarified, knowledge of the transcriptional regulation network underlying fruit cuticle formation remains limited. In the present work, we discovered that tomato fruits of the NAC transcription factor SlNOR-like1 knockout mutants (nor-like1) produced by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9] displayed reduced cutin deposition and cuticle thickness, with a microcracking phenotype, while wax accumulation was promoted. Further research revealed that SlNOR-like1 promotes cutin deposition by binding to the promoters of glycerol-3-phosphate acyltransferase6 (SlGPAT6; a key gene for cutin monomer formation) and CUTIN DEFICIENT2 (SlCD2; a positive regulator of cutin production) to activate their expression. Meanwhile, SlNOR-like1 inhibits wax accumulation, acting as a transcriptional repressor by targeting wax biosynthesis, and transport-related genes 3-ketoacyl-CoA synthase1 (SlKCS1), ECERIFERUM 1-2 (SlCER1-2), SlWAX2, and glycosylphosphatidylinositol-anchored lipid transfer protein 1-like (SlLTPG1-like). In conclusion, SlNOR-like1 executes a dual regulatory effect on tomato fruit cuticle development. Our results provide a new model for the transcriptional regulation of fruit cuticle formation.


Assuntos
Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Ceras/metabolismo
13.
Liver Int ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775078

RESUMO

BACKGROUND AND AIMS: The International AIH Pathology Group (IAIH-PG) put forward the new histological criteria of autoimmune hepatitis (AIH) in 2022, which have not undergone adequate verification. In this study, we verified the applicability of the new histological criteria in the population of Chinese patients with chronic liver disease, comparing it with the simplified criteria. METHODS: The gold standard for diagnosis in all patients was based on histological findings, combined with clinical manifestations and laboratory tests and determined after a follow-up period of at least 3 years. A total of 640 patients with various chronic liver diseases from multiple centres underwent scoring using the new histological criteria and the simplified criteria, comparing their diagnostic performance. RESULTS: In this study, the new histological criteria showed a sensitivity of 73.6% and 100% for likely and possible AIH, with specificities of 100% and 69.0% respectively. The coincidence rates of possible AIH for the new histological criteria, simplified histological criteria and simplified score were 81.7%, 72.8% and 69.7% respectively. For likely AIH, the rates were 89.2%, 75.9% and 65.6% respectively. Based on the new histological criteria, all patients with AIH were correctly diagnosed. Specifically, 73.6% were diagnosed with likely AIH and 26.4% were possible AIH. Additionally, the simplified histological criteria achieved a diagnosis rate of 98.6% for AIH, while the simplified score could only diagnose 53.8% of AIH. CONCLUSIONS: Compared with the simplified score and simplified histological criteria, the sensitivity and specificity of the new histological criteria for AIH were significantly improved. The results indicate that the new histological criteria exhibit high sensitivity and specificity for diagnosing AIH in China.

14.
Circ Res ; 131(9): e120-e134, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36164984

RESUMO

BACKGROUND: Despite available clinical management strategies, chronic kidney disease (CKD) is associated with severe morbidity and mortality worldwide, which beckons new solutions. Host-microbial interactions with a depletion of Faecalibacterium prausnitzii in CKD are reported. However, the mechanisms about if and how F prausnitzii can be used as a probiotic to treat CKD remains unknown. METHODS: We evaluated the microbial compositions in 2 independent CKD populations for any potential probiotic. Next, we investigated if supplementation of such probiotic in a mouse CKD model can restore gut-renal homeostasis as monitored by its effects on suppression on renal inflammation, improvement in gut permeability and renal function. Last, we investigated the molecular mechanisms underlying the probiotic-induced beneficial outcomes. RESULTS: We observed significant depletion of Faecalibacterium in the patients with CKD in both Western (n=283) and Eastern populations (n=75). Supplementation of F prausnitzii to CKD mice reduced renal dysfunction, renal inflammation, and lowered the serum levels of various uremic toxins. These are coupled with improved gut microbial ecology and intestinal integrity. Moreover, we demonstrated that the beneficial effects in kidney induced by F prausnitzii-derived butyrate were through the GPR (G protein-coupled receptor)-43. CONCLUSIONS: Using a mouse CKD model, we uncovered a novel beneficial role of F prausnitzii in the restoration of renal function in CKD, which is, at least in part, attributed to the butyrate-mediated GPR-43 signaling in the kidney. Our study provides the necessary foundation to harness the therapeutic potential of F prausnitzii for ameliorating CKD.


Assuntos
Faecalibacterium prausnitzii , Insuficiência Renal Crônica , Animais , Butiratos/farmacologia , Butiratos/uso terapêutico , Modelos Animais de Doenças , Inflamação , Rim/fisiologia , Receptores Acoplados a Proteínas G/genética
15.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515152

RESUMO

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Assuntos
Vias Biossintéticas , Policetídeo Sintases , Pirrolidinonas , Policetídeo Sintases/metabolismo , Bactérias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Peptídeo Sintases/genética
16.
J Org Chem ; 89(11): 8243-8248, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38753315

RESUMO

Herein we have pioneered an innovative synthetic strategy for the efficient assembly of various heteroarene-condensed benzofuran derivatives, utilizing benzofuran-derived azadienes (BDAs) and quinolines as the starting materials. This method functions with transition-metal catalysis and uses cost-effective formic acid as the reducing agent. Mechanistic investigations indicate that this transformation would involve a [4 + 2] annulation cascade process. This approach demonstrates a high tolerance to various functional groups and yields excellent results.

17.
Value Health ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38843980

RESUMO

OBJECTIVES: Controls and governance over the methodology and reporting of indirect treatment comparisons (ITCs) have been introduced to minimize bias and ensure scientific credibility and transparency in healthcare decision-making. The objective of this study was to highlight ITC techniques that are key to conducting objective and analytically-sound analyses, and to ascertain circumstantial suitability of ITCs as a source of comparative evidence for healthcare interventions. METHODS: Ovid MEDLINE® was searched from January 2010 through August 2023 to identify publicly available ITC-related documents (i.e., guidelines and best practices) in the English language. This was supplemented with hand-searches of websites of various international organizations, regulatory agencies, and reimbursement agencies of Europe, North America, and Asia-Pacific. The jurisdiction-specific ITC methodology and reporting recommendations were reviewed. RESULTS: Sixty-eight guidelines from 10 authorities worldwide were included for synthesis. Many of the included guidelines were updated within the last five years and commonly cited the absence of direct comparative studies as primary justification for employing ITCs. Most jurisdictions favored population-adjusted or anchored ITC techniques opposed to naïve comparisons. Recommendations on the reporting and presentation of these ITCs varied across authorities; however, there was some overlap among the key elements. CONCLUSIONS: Given the challenges of conducting head-to-head randomized controlled trials, comparative data from ITCs offer valuable insights into clinical effectiveness. As such, multiple ITC guidelines have emerged worldwide. According to the most recent versions of the guidelines, the suitability and subsequent acceptability of the ITC technique employed depends on the data sources, available evidence, and magnitude of benefit/uncertainty.

18.
Br J Nutr ; 131(1): 54-62, 2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37519248

RESUMO

Findings from observational studies have suggested a possible association between dietary inflammatory index (DII) and risk of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the results of these studies were inconclusive. A systematic review and meta-analysis was carried out to illuminate this association. Systematic literature search was conducted in PubMed, Web of Science, Cochrane Library, EMBASE, Scopus and other databases from inception until January 2023. The qualities of included studies were assessed using the Newcastle-Ottawa scale. Nine studies (seven cohort, two case-control) were included in the meta-analysis, including 11 423 participants from five different countries. The meta-analysis indicated that a 1-unit increase in the DII score, representing pro-inflammatory diet, was associated with 13 % higher risk of GDM (OR = 1·13; 95 % CI 1·02, 1·25, I2 = 68·4 %, P = 0·004) and 24 % higher risk of PE (OR = 1·24; 95 % CI 1·14, 1·35, I2 = 52·0 %, P = 0·125). Subgroup analysis found that this association was evident among studies with Chinese populations (OR = 1·16; 95 % CI 1·06, 1·28) and studies with mid pregnancy (OR = 1·20; 95 % CI 1·07, 1·34). The findings indicate that pro-inflammatory diet can increase the risk of GDM and PE. Considering some limitations in this study, more studies are needed to verify this association.


Assuntos
Diabetes Gestacional , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Diabetes Gestacional/etiologia , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/etiologia , Dieta/efeitos adversos
19.
Scand J Gastroenterol ; 59(1): 62-69, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37649307

RESUMO

BACKGROUND AND AIMS: There is no golden standard for the diagnosis of autoimmune hepatitis which still dependent on liver biopsy currently. So, we developed a noninvasive prediction model to help optimize the diagnosis of autoimmune hepatitis. METHODS: From January 2017 to December 2019, 1739 patients who had undergone liver biopsy were seen in the second hospital of Nanjing, of which 128 were here for consultation. Clinical, laboratory, and histologic data were obtained retrospectively. Multivariable logistic regression analysis was employed to create a nomogram model that predicting the risk of autoimmune hepatitis. Internal and external validation was both performed to evaluate the model. RESULTS: A total of 1288 patients with liver biopsy were enrolled (1184 from the second hospital of Nanjing, the remaining 104 from other centers). After the univariate and multivariate logistic regression analysis, nine variables including ALT, IgG, ALP/AST, ALB, ANA, AMA, HBsAg, age, and gender were selected to establish the noninvasive prediction model. The nomogram model exhibits good prediction in diagnosing autoimmune hepatitis with AUROC of 0.967 (95% CI: 0.776-0.891) in internal validation and 0.835 (95% CI: 0.752-0.919) in external validation. CONCLUSIONS: ALT, IgG, ALP/AST, ALB, ANA, AMA, HBsAg, age, and gender are predictive factors for the diagnosis of autoimmune hepatitis in patients with unexplained liver diseases. The predictive nomogram model built by the nine predictors achieved good prediction for diagnosing autoimmune hepatitis.


Assuntos
Hepatite Autoimune , Humanos , Hepatite Autoimune/complicações , Hepatite Autoimune/diagnóstico , Estudos Retrospectivos , Antígenos de Superfície da Hepatite B , Nomogramas , Imunoglobulina G
20.
BMC Cardiovasc Disord ; 24(1): 60, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243161

RESUMO

BACKGROUND: The triglyceride glucose-body mass index (TyG-BMI index) has been suggested as a novel predictor of insulin resistance. However, its predictive value for slow coronary flow phenomenon (SCFP) in patients with ischemia and nonobstructive coronary arteries (INOCA) remains unclear. METHODS: We consecutively recruited 1625 patients with INOCA from February 2019 to February 2023 and divided them into two groups based on thrombolysis in myocardial infarction (TIMI) frame counts (TFCs): the SCFP group (n = 79) and the control group. A 1:2 age-matched case-control study was then performed. The TyG-BMI index was calculated as ln [plasma triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI. RESULTS: TyG-BMI index in the SCFP group (218.3 ± 25.2 vs 201.0 ± 26.5, P < .001) was significantly higher than in the normal controls. TyG-BMI index also increased with the number of coronary arteries involved in the SCFP. Multivariate logistic regression analysis showed that TyG-BMI, BMI, and TG were independent predictors for SCFP. Receiver operating characteristic (ROC) curve analysis showed that when the TyG-BMI index was above 206.7, the sensitivity and specificity were 88.6% and 68.5%, respectively, with an AUC of 0.809 (95% CI: 0.756-0.863, P = .027). Combined BMI with TG, the TyG-BMI index had a better predictive value for SCFP than BMI and TG (P < .001). CONCLUSION: The TyG-BMI index was an independent predictor for SCFP in INOCA patients, and it had a better predictive value than BMI and TG.


Assuntos
Glucose , Fenômeno de não Refluxo , Humanos , Índice de Massa Corporal , Glicemia , Vasos Coronários , Triglicerídeos , Estudos de Casos e Controles , Biomarcadores , Isquemia , Fenômeno de não Refluxo/diagnóstico por imagem , Fenômeno de não Refluxo/etiologia
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