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1.
BMC Immunol ; 25(1): 10, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297222

RESUMEN

PURPOSE: More than 90% of patients with diabetes worldwide are type 2 diabetes (T2D), which is caused by insulin resistance or impaired producing insulin by pancreatic ß cells. T2D and its complications, mainly large cardiovascular (LCV) and kidney (Ne) complications, are the major cause of death in diabetes patients. Recently, the dysregulation of peripheral T cell immune homeostasis was found in most T2D patients. However, the characteristics of T-cell receptors (TCR) remain largely unexplored in T2D patients. PATIENTS AND METHODS: Here we investigated the TCR repertoire using high-throughput sequencing in peripheral blood collected from T2D patient with (8 LCV and 7 Ne) or without complications. RESULTS: Our analysis of TCR repertoires in peripheral blood samples showed that TCR profiles in T2D patients with complications tended to be single and specific compared to controls, according to the characteristics of TCR repertoire in V-J combination number, diversity, principal component analysis (PCA) and differential genes. And we identified some differentially expressed V-J gene segments and amino acid clonotypes, which had the potential to contribute to distinguishing T2D patient with or without complications. As the progression of the disease, we found that the profiling of TCR repertoire was also differential between T2D patients with LVD and Ne complications base on this pilot analysis. CONCLUSION: This study demonstrated the protentional unique property of TCR repertoire in peripheral blood of T2D patient with and without complications, or T2D patients with LVD and Ne complications, which provided the possibility for future improvements in immune-related diagnosis and therapy for T2D complications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Linfocitos T , Humanos , Receptores de Antígenos de Linfocitos T/genética , Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T alfa-beta/genética
2.
J Org Chem ; 89(12): 8537-8545, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38861493

RESUMEN

The current methods for synthesizing acylhydrazones are limited by their multistep processes, narrow substrate scope, low selectivities, and poor yields. Herein, a fundamentally novel approach to bioactive acylhydrazones was developed based on the palladium-catalyzed multicomponent tandem condensation carbonylation of halides with aldehydes and hydrazines. This method provides a useful and efficient strategy for generating grams of various acylhydrazones in a one-pot manner. Mechanistic studies provided evidence of facile carbonylation of halides with the weak nucleophile hydrazones facilitated by a base.

3.
J Org Chem ; 89(4): 2605-2621, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38315164

RESUMEN

A practical base-promoted tandem condensation N-alkylation reaction for the formation of trisubstituted hydrazones has been developed employing aldehydes and hydrazines with alkyl halides. Crucially, this reaction successfully overcomes chemoselectivity problems, allowing for the reaction of multiple components in a one-pot manner. Halo- and heterofunctional groups, as well as free hydroxyl and amino groups, are tolerated in this transformation to produce a wide range of trisubstituted hydrazones in good to excellent yields.

4.
J Appl Toxicol ; 44(3): 344-354, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37718569

RESUMEN

Narcissin is a natural flavonoid from some edible and traditional medicinal plants. It has been proven to have multiple biological functions and exhibits potential therapeutic effects on hypertension, cancer, and Alzheimer's disease. However, the toxicity of narcissin is largely unknown. Here, we revealed that narcissin treatment led to reduced hatchability, increased malformation rate, shorter body length, and slowed blood flow in zebrafish. Furthermore, bradycardia, pericardial edema, increased SV-BA distance, diminished stroke volume, ejection fraction, and ventricular short-axis shortening rate were also found. A large accumulation of ROS, increased apoptotic cells, and histopathological changes were detected in the heart region. Moreover, the gene expression profiles and molecular docking analysis indicated that Nrf2/HO-1 and calcium signaling pathways were involved in narcissin-induced toxicity. In conclusion, here we provide the first evidence that demonstrates narcissin-induced developmental toxicity and cardiotoxicity in zebrafish via Nrf2/HO-1 and calcium signaling pathways for the first time.


Asunto(s)
Flavonoles , Factor 2 Relacionado con NF-E2 , Pez Cebra , Animales , Pez Cebra/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Cardiotoxicidad , Señalización del Calcio , Simulación del Acoplamiento Molecular , Embrión no Mamífero , Estrés Oxidativo
5.
PLoS Genet ; 17(8): e1009693, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34351909

RESUMEN

The ubiquitin-proteasome system plays important roles in various biological processes as it degrades the majority of cellular proteins. Adequate proteasomal degradation of crucial transcription regulators ensures the proper development of neutrophils. The ubiquitin E3 ligase of Growth factor independent 1 (GFI1), a key transcription repressor governing terminal granulopoiesis, remains obscure. Here we report that the deficiency of the ring finger protein Interferon regulatory factor 2 binding protein 2a (Irf2bp2a) leads to an impairment of neutrophils differentiation in zebrafish. Mechanistically, Irf2bp2a functions as a ubiquitin E3 ligase targeting Gfi1aa for proteasomal degradation. Moreover, irf2bp2a gene is repressed by Gfi1aa, thus forming a negative feedback loop between Irf2bp2a and Gfi1aa during neutrophils maturation. Different levels of GFI1 may turn it into a tumor suppressor or an oncogene in malignant myelopoiesis. Therefore, discovery of certain drug targets GFI1 for proteasomal degradation by IRF2BP2 might be an effective anti-cancer strategy.


Asunto(s)
Proteínas de Unión al ADN/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/crecimiento & desarrollo , Animales , Proteínas de Unión al ADN/metabolismo , Retroalimentación Fisiológica , Femenino , Regulación de la Expresión Génica , Técnicas de Inactivación de Genes , Células HEK293 , Células HL-60 , Humanos , Leucopoyesis , Masculino , Proteolisis , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
6.
Environ Toxicol ; 39(9): 4417-4430, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38842024

RESUMEN

Gliomas are the most prevalent primary malignant brain tumors worldwide. Growing evidences indicate that circular RNAs (circRNAs) play an important role in the regulation of biological behavior of tumors. We aimed to investigate the role and mechanism of circVCAN in glioma. RNase R treatment was utilized to assess the cyclic properties of circVCAN. CircVCAN, miR-488-3p, and myocyte enhancer factor 2C (MEF2C) levels in glioma tissues and cells were detected by reverse transcription real-time polymerase chain reaction (RT-qPCR), and the localization of them in glioma cells was determined with fluorescence in situ hybridization. Furthermore, a variety of biologically functional assessments were used to validate the role of circVCAN in glioma. The regulatory mechanisms of circVCAN, miR-488-3p, and MEF2C were further confirmed by double luciferase reporter gene assay, RNA immunoprecipitation and RNA pull-down assay, and the binding of MEF2C to JAGGED1 was revealed by chromatin immunoprecipitation. Additionally, a xenograft tumor model was constructed to demonstrate the effect of circVCAN on tumor growth in vivo. Our results indicated that circVCAN was more stable than its linear RNA and was significantly upregulated in gliomas. CircVCAN overexpression stimulated glioma cells to proliferate and metastasize, but circVCAN silencing exerted the opposite effect. Meanwhile, silencing circVCAN inhibited tumor growth in vivo. Moreover, we found that circVCAN interacted with miR-488-3p to regulate MEF2C expression, and miR-488-3p inhibition or MEF2C overexpression reversed the inhibitory effect on malignant bio-behaviors mediated by circVCAN knockdown in glioma cells. MEF2C promoted the transcription of JAGGED1, and circVCAN knockdown reduced the binding between MEF2C and JAGGED1. Collectively, circVCAN is a carcinogenic circRNA in glioma, and the circVCAN/miR-488-3p/MEF2C-JAGGED1 axis could serve as a potential target for the management of glioma.


Asunto(s)
Neoplasias Encefálicas , Glioma , Proteína Jagged-1 , Factores de Transcripción MEF2 , MicroARNs , ARN Circular , Factores de Transcripción MEF2/genética , Factores de Transcripción MEF2/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Glioma/genética , Glioma/patología , ARN Circular/genética , ARN Circular/metabolismo , Línea Celular Tumoral , Animales , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Ratones Desnudos , Ratones , Ratones Endogámicos BALB C , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Masculino , Progresión de la Enfermedad
7.
Exp Appl Acarol ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150623

RESUMEN

The two-spotted spider mite (Tetranychus urticae Koch, TSSM) is recognized as one of the most problematic spider mite pests. However, the precise gene expression patterns across its key developmental stages remain elusive. Here, we performed a comprehensive transcriptome analysis of TSSM eggs, nymphs and adult females using publicly available RNA sequencing (RNA-seq) data to elucidate the overarching transcriptomic differences between these developmental stages. Principal component analysis and hierarchical clustering analysis unveiled distinct separations among samples across different developmental stages, regardless of their Wolbachia infection status. Differential expression analysis revealed 4,089,2,762, and 1,282 core genes specifically enriched in eggs, nymphs, and adults, respectively. KEGG and GO enrichment analyses showed upregulation of genes in eggs are associated with proteolysis, Wnt signaling pathway, DNA transcription, RNA biosynthetic and metabolic processes, as well as protein folding, sorting, and degradation pathways. Meanwhile, nymphs exhibited increased abundance of genes related to chitin/amino sugar metabolic processes, G protein-coupled receptor signaling pathways, monoatomic ion transport, and neurotransmitter transport pathways. Pathways involving sphingolipid and carbohydrate metabolic processes, proteolysis, lipid transport, and localization were particularly enriched in older females. Altogether, our findings suggest that the egg stage exhibits higher activity in cell differentiation processes, the nymph stage is more involved in chitin development, and the adult stage shows increased metabolic and reproductive activity. This study enhances our understanding of the molecular mechanisms underlying TSSM development and paves the way for further research into the intricate physiological processes of TSSM.

8.
J Virol ; 96(15): e0078622, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35861516

RESUMEN

The M1 of influenza A virus (IAV) is important for the virus life cycle, especially for the assembly and budding of viruses, which is a multistep process that requires host factors. Identifying novel host proteins that interact with M1 and understanding their functions in IAV replication are of great interest in antiviral drug development. In this study, we identified 19 host proteins in DF1 cells suspected to interact with the M1 protein of an H5N6 virus through immunoprecipitation (IP)/mass spectrometry. Among them, PSMD12, a 26S proteasome regulatory subunit, was shown to interact with influenza M1, acting as a positive host factor in IAV replication in avian and human cells. The data showed that PSMD12 promoted K63-linked ubiquitination of M1 at the K102 site. H5N6 and PR8 with an M1-K102 site mutant displayed a significantly weaker replication ability than the wild-type viruses. Mechanistically, PSMD12 promoted M1-M2 virus-like particle (VLP) release, and an M1-K102 mutation disrupted the formation of supernatant M1-M2 VLPs. An H5N6 M1-K102 site mutation or knockdown PSMD12 disrupted the budding release of the virus in chicken embryo fibroblast (CEF) cells, which was confirmed by transmission electron microscopy. Further study confirmed that M1-K102 site mutation significantly affected the virulence of H5N6 and PR8 viruses in mice. In conclusion, we report the novel host factor PSMD12 which affects the replication of influenza virus by mediating K63-linked ubiquitination of M1 at K102. These findings provide novel insight into the interactions between IAV and host cells, while suggesting an important target for anti-influenza virus drug research. IMPORTANCE M1 is proposed to play multiple biologically important roles in the life cycle of IAV, which relies largely on host factors. This study is the first one to identify that PSMD12 interacts with M1, mediates K63-linked ubiquitination of M1 at the K102 site, and thus positively regulates influenza virus proliferation. PSMD12 promoted M1-M2 VLP egress, and an M1-K102 mutation affected the M1-M2 VLP formation. Furthermore, we demonstrate the importance of this site to the morphology and budding of influenza viruses by obtaining mutant viruses, and the M1 ubiquitination regulator PSMD12 has a similar function to the M1 K102 mutation in regulating virus release and virus morphology. Additionally, we confirm the reduced virulence of H5N6 and PR8 (H1N1) viruses carrying the M1-K102 site mutation in mice. These findings provide novel insights into IAV interactions with host cells and suggest a valid and highly conserved candidate target for antiviral drug development.


Asunto(s)
Interacciones Huésped-Patógeno , Virus de la Influenza A , Complejo de la Endopetidasa Proteasomal , Ubiquitinación , Proteínas de la Matriz Viral , Replicación Viral , Animales , Antivirales , Línea Celular , Embrión de Pollo , Fibroblastos , Humanos , Subtipo H1N1 del Virus de la Influenza A/química , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Virus de la Influenza A/genética , Virus de la Influenza A/crecimiento & desarrollo , Virus de la Influenza A/metabolismo , Virus de la Influenza A/patogenicidad , Ratones , Mutación , Complejo de la Endopetidasa Proteasomal/química , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas de la Matriz Viral/química , Proteínas de la Matriz Viral/genética , Proteínas de la Matriz Viral/metabolismo , Virulencia/genética
9.
Neurochem Res ; 48(3): 956-966, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36402927

RESUMEN

Ferroptosis is characterized by excessive accumulation of iron and lipid peroxides, which are involved in ischemia, reperfusion-induced organ injury, and stroke. Propofol, an anesthetic agent, has neuroprotective effects due to its potent antioxidant, anti-ischemic, and anti-inflammatory properties. However, the relationship between propofol and ferroptosis is still unclear. In the current study, we elucidated the role of ferroptosis in the neuroprotective effect of propofol in mouse brains subjected to cerebral ischemia reperfusion injury (CIRI). Ferroptosis was confirmed by Western blotting assays, transmission electron microscopy, and glutathione assays. Propofol regulated Nrf2/Gpx4 signaling, enhanced antioxidant potential, inhibited the accumulation of lipid peroxides in CIRI-affected neurons, and significantly reversed CIRI-induced ferroptosis. Additionally, Gpx4 inhibitor RSL3 and Nrf2 inhibitor ML385 attenuated the effects of propofol on antioxidant capacity, lipid peroxidation, and ferroptosis in CIRI-affected neurons. Our data support a protective role of propofol against ferroptosis as a cause of cell death in mice with CIRI. Propofol protected against CIRI-induced ferroptosis partly by regulating the Nrf2/Gpx4 signaling pathway. These findings may contribute to the development of future therapies targeting ferroptosis induced by CIRI.


Asunto(s)
Propofol , Daño por Reperfusión , Animales , Ratones , Propofol/farmacología , Propofol/uso terapéutico , Factor 2 Relacionado con NF-E2 , Antioxidantes , Peróxidos Lipídicos , Daño por Reperfusión/tratamiento farmacológico , Modelos Animales de Enfermedad , Transducción de Señal , Muerte Celular
10.
Microb Ecol ; 87(1): 1, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37991578

RESUMEN

Microbes play a key role in the biology, ecology, and evolution of arthropods. Despite accumulating data on microbial communities in arthropods that feed on plants using piercing-sucking mouthparts, we still lack a comprehensive understanding of the composition and assembly factors of the microbiota, particularly in field-collected spider mites. Here, we applied 16S rRNA amplicon sequencing to investigate the characters of the bacterial community in 140 samples representing 420 mite individuals, belonging to eight Tetranychus species (Acari: Tetranychidae) collected from 26 sites in China. The results showed that the bacterial composition of spider mites varied significantly among different species, locations, and plants. The environment showed a significant influence on the bacterial community of spider mites, with different relative contributions. Latitude and precipitation were found to be the main factors influencing the bacterial community composition. The dissimilarity of bacterial community and geographical distance between mite locations were significantly correlated. The assembly of spider mite bacterial communities seemed to be mainly influenced by stochastic processes. Furthermore, the symbiont Cardinium was found to be important in shaping the microbiota of many Tetranychus species. The relative abundance of Cardinium was > 50% in T. viennensis, T. urticae G, T. urticae R, and T. turkestani. Removing Cardinium reads from our analysis significantly changed Shannon diversity index and weighted beta diversity in these species. Altogether, this study provides novel insights into bacterial diversity patterns that contribute to our knowledge of the symbiotic relationships between arthropods and their bacterial communities.


Asunto(s)
Artrópodos , Microbiota , Tetranychidae , Humanos , Animales , ARN Ribosómico 16S/genética , Bacteroidetes/genética
11.
Macromol Rapid Commun ; 44(15): e2300136, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37099331

RESUMEN

In order to enhance the thermal conductivity of polytetrafluoroethylene (PTFE)-based composites, while maintaining relatively low dielectric constant and dielectric loss for high-frequency and high-speed applications, hexagonal boron nitride (hBN) and silicon carbide (SiC) compounded fillers are filled into the PTFE matrix. The hBN/SiC/PTFE composites are prepared by pulse vibration molding (PVM), and their subsequent thermal conductivities are comparatively investigated. The PVM process with controlled fluctuation in pressure (1 Hz square wave force, 0-20 MPa, at 150 °C) can reduce the sample porosity and surface defects, improve the orientation of hBN, and increase the thermal conductivity by 44.6% compared with that obtained by compression molding. When hBN:SiC (vol) is 3:1, the in-plane thermal conductivity of the composite with 40 vol% filler content is ≈4.83 W m-1  K-1 , which is 40.3% higher than that of hBN/PTFE. Regarding the dielectric properties, hBN/SiC/PTFE maintains a low dielectric constant of 3.27 and a low dielectric loss of 0.0058. The dielectric constants of hBN/SiC/PTFE ternary composites are predicted by using different prediction models, among which the effective medium theory (EMT), is in good agreement with the experimental results. PVM shows great potential in the large-scale preparation of thermal conductive composites for high-frequency and high-speed applications.


Asunto(s)
Politetrafluoroetileno , Vibración , Conductividad Térmica
12.
J Nat Prod ; 86(5): 1189-1201, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37083418

RESUMEN

The pathogenesis of nonalcoholic fatty liver disease (NAFLD) is closely linked to the imbalance of lipid and glucose metabolism, in which peroxisome proliferator-activated receptors (PPARs) play essential roles. The clinical trials have shown the beneficial effects of the PPARs' ligands on NAFLD. In this study, we screen the extracts from the marine fungus Acremonium citrinum and identify the natural compounds dihydrotrichodimerol (L1A) and trichodimerol (L1B) as the ligands of PPARs, of which L1A is a dual PPARα/γ agonist, whereas L1B is a selective PPARγ agonist. L1A but not L1B significantly prevents hepatic lipid accumulation in an oleic acid-induced NAFLD cell model as well as in a high-fat-diet-induced NAFLD mouse model. Moreover, L1A potently inhibits hepatic steatosis in a PPARα-dependent manner in another NAFLD mouse model constructed by using a choline-deficient and amino acid-defined diet. Mechanistically, L1A transcriptionally up-regulates the expression of SIRT1 in a PPARα-dependent manner, followed by the activation of AMPK and inactivation of ACC, resulting in the inhibition of lipid anabolism and the increase of lipid catabolism. Taken together, our study reveals a dual ligand of PPARα/γ with a distinct structure and therapeutic effect on NAFLD, providing a potential drug candidate bridging the currently urgent need for the management of NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/prevención & control , PPAR alfa/agonistas , Metabolismo de los Lípidos , Hígado , Ácido Oléico/farmacología
13.
Int J Mol Sci ; 24(10)2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37240113

RESUMEN

A new prenylated indole alkaloid-Penicimutamide C N-oxide (1), a new alkaloid penicimutamine A (2), along with six known alkaloids were isolated from an endophytic fungus Pallidocercospora crystallina. A simple and accurate method was used to determine the N-O bond in the N-oxide group of 1. By using a ß-cell ablation diabetic zebrafish model, compounds 1, 3, 5, 6 and 8 showed significantly hypoglycemic activities under the concentration of 10 µM. Further studies revealed that compounds 1 and 8 lowered the glucose level through promoting glucose uptake in zebrafish. In addition, all eight compounds showed no acute toxicity, teratogenicity, nor vascular toxicity in zebrafish under the concentrations range from 2.5 µΜ to 40 µM. Importantly, these results provide new lead compounds for the development of antidiabetes strategies.


Asunto(s)
Alcaloides , Pez Cebra , Animales , Hipoglucemiantes/farmacología , Alcaloides Indólicos/química , Alcaloides/química , Estructura Molecular
14.
Arch Microbiol ; 204(6): 333, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585303

RESUMEN

Small colony variants (SCVs) are a slow-growing subpopulation of bacteria characterized by their atypical colony morphology and distinct biochemical properties, which are known to cause chronic persistent infections. Here, we investigated the characteristics of three phenotypes of Escherichia coli, including a capnophilic SCV, co-isolated from a 64-year-old patient with bacteremia in China. The three strains were identified as a capnophilic strain (EC1), a capnophilic SCV (EC2), and a normal colony strain (EC3). The EC1 and EC2 strains did not grow in the absence of CO2, while the EC2 colonies were pinpoint in appearance and had the ability to revert to the normal colony phenotype. The growth of the SCV was slow and not enhanced in the presence of thymidine, hemin, thiamine, and menadione. The results of antimicrobial susceptibility among the three strains showed similar sensitivity to cefoxitin and imipenem, but resistant to most of the other antimicrobials tested. Whole-genome sequencing showed that no genetic mutational variations associated with SCVs were observed, while EC1, EC2 and the revertible strains of EC2 lacked the can gene. Multi-locus sequence typing showed that all strains belonged to ST457 and nucleotide similarity analysis indicated that they had high homology. In conclusion, we report rarely described co-isolated forms of three phenotypes of E. coli that included a capnophilic SCV in a patient with bacteremia. The capnophilic SCV strain had atypical morphology and biochemical characteristics in the absence of can gene. Based on our findings, we have discussed the laboratory identification, characterization, mechanisms, and clinical treatment of capnophilic SCV strains.


Asunto(s)
Bacteriemia , Infecciones por Escherichia coli , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Escherichia coli/genética , Humanos , Tipificación de Secuencias Multilocus , Fenotipo , Infecciones Estafilocócicas/microbiología
15.
Org Biomol Chem ; 20(45): 8912-8916, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36321617

RESUMEN

Iminolactones are an important class of heterocyclic compounds. Thus, the development of an efficient strategy for their preparation becomes highly desirable. A new method for the transformation of carboxamides into iminolactones via copper-catalyzed intramolecular C(sp3)-H bond functionalization is reported herein. A series of primary, secondary and tertiary C(sp3)-H bonds were all accommodated to afford iminolactones through a cascade process which involves amidyl radical intermediate generation, 1,5-HAT (hydrogen atom transfer), and ensuing cyclization.


Asunto(s)
Cobre , Compuestos Heterocíclicos , Ciclización , Cobre/química , Catálisis , Hidrógeno/química
16.
Int Endod J ; 55(3): 263-274, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34807471

RESUMEN

AIM: To evaluate the effects of hsa-miRNA-143-3p on the cytodifferentiation of human stem cells from the apical papilla (hSCAPs) and the post-transcriptional regulation of Nuclear factor I-C (NFIC). METHODOLOGY: miRNA expression profiles in human immature permanent teeth and during hSCAP differentiation were examined. hSCAPs were treated with miR-143-3p overexpression or silencing viruses, and the proliferation and odontogenic and osteogenic differentiation of these stem cells, and the involvement of the NFIC pathway, were investigated. Luciferase reporter and NFIC mutant plasmids were used to confirm NFIC mRNA as a direct target of miR-143-3p. NFIC expression analysis in the miR-143-3p overexpressing hSCAPs was used to investigate whether miR-143-3p functioned by targeting NFIC. Student's t-test and chi-square tests were used for statistical analysis. RESULTS: miR-143-3p expression was screened by microarray profiling and was found to be significantly reduced during hSCAP differentiation (p < .05). Overexpression of miR-143-3p inhibited the mineralization of hSCAPs significantly (p < .05) and downregulated the levels of odontogenic differentiation markers (NFIC [p < .05], DSP [p < .01] and KLF4 [p < .01]), whereas silencing of miR-143-3p had the opposite effect. The luciferase reporter gene detection and bioinformatic approaches identified NFIC mRNA as a potential target of miR-143-3p. NFIC overexpression reversed the inhibitory effect of miR-143-3p on the odontogenic differentiation of hSCAPs. CONCLUSIONS: miR-143-3p maintained the stemness of hSCAPs and modulated their differentiation negatively by directly targeting NFIC. Thus, inhibition of this miRNA represents a potential strategy to promote the regeneration of damaged tooth roots.


Asunto(s)
Diferenciación Celular , Papila Dental/citología , MicroARNs , Factores de Transcripción NFI , Células Cultivadas , Humanos , MicroARNs/genética , Factores de Transcripción NFI/genética , Osteogénesis , Células Madre
17.
Ecotoxicol Environ Saf ; 248: 114335, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36442399

RESUMEN

Recently, there has been increasing concern about the health hazards of heavy metal-polluted farmlands. Recent findings suggest that intercropping could be effective remediation strategy for agricultural soils without affecting crop biomass yield. However, there are concerns on the heavy metal accumulation in plant organs in phytoremediation, emphasizing the need to develop an effective intercropping remediation model. In this study, we evaluated the effects of intercropping rape and wheat with different accumulation characteristics of cadmium (Cd), and crop growth and physiological characteristics. Intercropping significantly reduced the Cd content of rape shoot and root, with the rape-low Cd-accumulating wheat intercropping system yielding the best results. However, intercropping had no significant effect on Cd accumulation in wheat. Additionally, intercropping affected the root system configuration and structure, photosynthetic indicators, chlorophyll content, crop enzyme content, and rhizosphere enzyme activity of both species, but did not significantly affect the biomass of wheat and rape. Overall, our findings showed that intercropping rape with a low Cd-accumulating wheat variety could be an effective model for safe production of wheat and rape in weak alkaline soils without compromising biomass yield. The study demonstrates that similar innovative, effective, and judicious intercropping strategy can enrich the theory of contaminated soil remediation.


Asunto(s)
Violación , Triticum , Cadmio , Suelo , Biomasa
18.
Int Orthop ; 46(10): 2393-2403, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35852654

RESUMEN

PURPOSE: The removal of three inverted triangular parallel cannulated screws after the femoral neck fracture healing is sometimes accompanied by osteonecrosis of the femoral head (ONFH) or its refracture. The purpose of this study was to determine the biomechanical changes of the femur before and after the screw removal using a finite element analysis. METHODS: The CT data of the femurs were obtained from a 69-year-old healthy female to establish the femur models. The established finite element models consisted of N, C, and R groups: N group, the normal femur; C group (to simulate the femoral neck fracture healing after the internal fixation), the normal femur with three inverted triangular parallel cannulated screws (C1) or with two upper parallel screws (C2). For the R1 or R2 groups, the screws in the model of the C1 or C2 individuals were gradually removed in seven or three types of different screw combinations, respectively. The stresses and displacements of the femur were determined. RESULTS: (1) Compared with the N group, a uniform stress distribution was stopped by the addition of three screws in the C1 group; in contrast, all screw removals resulted in the stress concentration on the screw holes and the disappearance of stress shielding. Moreover, the average stress of the femoral head in C1 group increased by 37.85%, while that of the femoral neck decreased by 23.03%. (2) Compared with the C1 group, while only the lowest femoral calcar screw was removed, there was a similar stress distribution in the proximal femur, and the average stress of the femoral head increased only by 0.35% although that of the femoral neck increased by 63.62%; however, removal by any other means resulted in a significant stress concentration in the proximal femur and a significant increase in the average stresses of the femoral head and neck (5.96-40.95% and 12.82-75.46%, respectively). (3) Compared with the N or C1 group, there was a significant stress concentration on the screws and its surrounding proximal femur in the C2 group. (4) Compared with the C2 group, the simultaneous removal of two upper screws not only did not cause a significant stress concentration on the proximal femur but also significantly reduced the average stresses of the femoral head and neck by 87.49% and 65.51% respectively. On the contrary, the gradual removal of two screws caused a significant stress concentration on the screw and its surrounding proximal femur although the average stresses of the femoral head and neck decreased by 88.79-89.06% and 67.00-67.22%, respectively. (5) Compared with the N group, the average displacements of the femoral head and neck in the C1 group increased only by 3.12% and 3.37%, respectively. Additionally, compared with the C1 group, while three, two, or one screw was simultaneously removed, the average displacements of the femoral head and neck only fluctuated - 5.51-1.65% and 1.78-9.03%, respectively. CONCLUSIONS: Residual internal fixation after femoral neck fracture healing may lead to stress concentration on screws and stress shielding around screws. The first removal of the lowest femoral calcar screw and then the second removal of two upper residual screws have a minimum effect on the stress concentration on the proximal femur and the average stress on the femoral head. The incorrect screw removal and resulting femoral load may well be closely related to occurrence in ONFH or its refracture.


Asunto(s)
Fracturas del Cuello Femoral , Anciano , Fenómenos Biomecánicos , Tornillos Óseos , Femenino , Fracturas del Cuello Femoral/cirugía , Fémur/cirugía , Análisis de Elementos Finitos , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Humanos
19.
Int J Mol Sci ; 23(23)2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36499197

RESUMEN

Downy mildew is a major threat to the economic value of spinach. The most effective approach to managing spinach downy mildew is breeding cultivars with resistance genes. The resistance allele RPF2 is effective against races 1-10 and 15 of Peronospora farinosa f. sp. Spinaciae (P. effusa) and is widely used as a resistance gene. However, the gene and the linked marker of RPF2 remain unclear, which limit its utilization. Herein, we located the RPF2 gene in a 0.61 Mb region using a BC1 population derived from Sp39 (rr) and Sp62 (RR) cultivars via kompetitive allele specific PCR (KASP) markers. Within this region, only one R gene, Spo12821, was identified based on annotation information. The amino acid sequence analysis showed that there were large differences in the length of the LRR domain between the parents. Additionally, a molecular marker, RPF2-IN12821, was developed based on the sequence variation in the Spo12821, and the evaluation in the BC1 population produced a 100% match with resistance/susceptibility. The finding of the study could be valuable for improving our understanding of the genetic basis of resistance against the downy mildew pathogen and breeding resistance lines in the future.


Asunto(s)
Oomicetos , Peronospora , Spinacia oleracea/genética , Enfermedades de las Plantas/genética , Fitomejoramiento
20.
Haematologica ; 105(2): 325-337, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31123027

RESUMEN

Aproper choice of neutrophil-macrophage progenitor cell fate is essential for the generation of adequate myeloid subpopulations during embryonic development and in adulthood. The network governing neutrophil-macrophage progenitor cell fate has several key determinants, such as myeloid master regulators CCAAT enhancer binding protein alpha (C/EBPα) and spleen focus forming virus proviral integration oncogene (PU.1). Nevertheless, more regulators remain to be identified and characterized. To ensure balanced commitment of neutrophil-macrophage progenitors toward each lineage, the interplay among these determinants is not only synergistic, but also antagonistic. Depletion of interferon regulatory factor 2 binding protein 2b (Irf2bp2b), a well-known negative transcription regulator, results in a bias in neutrophil-macrophage progenitor cell fate in favor of macrophages at the expense of neutrophils during the stage of definitive myelopoiesis in zebrafish embryos. Mechanistic studies indicate that Irf2bp2b acts as a downstream target of C/EBPα, repressing PU.1 expression, and that SUMOylation confers the repressive function of Irf2bp2b. Thus, Irf2bp2b is a novel determinant in the choice of fate of neutrophil-macrophage progenitor cells.


Asunto(s)
Proteínas de Unión al ADN/genética , Mielopoyesis , Factores de Transcripción/genética , Proteínas de Pez Cebra/genética , Pez Cebra , Animales , Proteínas Portadoras , Diferenciación Celular , Macrófagos , Neutrófilos
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