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1.
FASEB J ; 38(16): e70002, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39162680

RESUMO

Breast cancer is one of the threatening malignant tumors with the highest mortality and incidence rate over the world. There are a lot of breast cancer patients dying every year due to the lack of effective and safe therapeutic drugs. Therefore, it is highly necessary to develop more effective drugs to overcome breast cancer. As a glycoside derivative of apigenin, cosmosiin is characterized by low toxicity, high water solubility, and wide distribution in nature. Additionally, cosmosiin has been shown to perform anti-tumor effects in cervical cancer, hepatocellular carcinoma and melanoma. However, its pharmacological effects on breast cancer and its mechanisms are still unknown. In our study, the anti-breast cancer effect and mechanism of cosmosiin were investigated by using breast cancer models in vivo and in vitro. The results showed that cosmosiin inhibited the proliferation, migration, and adhesion of breast cancer cells in vitro and suppressed the growth of tumor in vivo through binding with AhR and inhibiting it, thus regulating the downstream CYP1A1/AMPK/mTOR and PPARγ/Wnt/ß-catenin signaling pathways. Collectively, our findings have made contribution to the development of novel drugs against breast cancer by targeting AhR and provided a new direction for the research in the field of anti-breast cancer therapy.


Assuntos
Neoplasias da Mama , Proliferação de Células , Citocromo P-450 CYP1A1 , PPAR gama , Receptores de Hidrocarboneto Arílico , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , PPAR gama/metabolismo , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Camundongos , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A1/genética , Proliferação de Células/efeitos dos fármacos , Camundongos Nus , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Camundongos Endogâmicos BALB C , Movimento Celular/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Via de Sinalização Wnt/efeitos dos fármacos
2.
Mol Psychiatry ; 29(3): 793-808, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145987

RESUMO

Context-induced retrieval of drug withdrawal memory is one of the important reasons for drug relapses. Previous studies have shown that different projection neurons in different brain regions or in the same brain region such as the basolateral amygdala (BLA) participate in context-induced retrieval of drug withdrawal memory. However, whether these different projection neurons participate in the retrieval of drug withdrawal memory with same or different molecular pathways remains a topic for research. The present results showed that (1) BLA neurons projecting to the prelimbic cortex (BLA-PrL) and BLA neurons projecting to the nucleus accumbens (BLA-NAc) participated in context-induced retrieval of morphine withdrawal memory; (2) there was an increase in the expression of Arc and pERK in BLA-NAc neurons, but not in BLA-PrL neurons during context-induced retrieval of morphine withdrawal memory; (3) pERK was the upstream molecule of Arc, whereas D1 receptor was the upstream molecule of pERK in BLA-NAc neurons during context-induced retrieval of morphine withdrawal memory; (4) D1 receptors also strengthened AMPA receptors, but not NMDA receptors, -mediated glutamatergic input to BLA-NAc neurons via pERK during context-induced retrieval of morphine withdrawal memory. These results suggest that different projection neurons of the BLA participate in the retrieval of morphine withdrawal memory with diverse molecular pathways.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Morfina , Neurônios , Núcleo Accumbens , Síndrome de Abstinência a Substâncias , Animais , Complexo Nuclear Basolateral da Amígdala/metabolismo , Masculino , Síndrome de Abstinência a Substâncias/metabolismo , Síndrome de Abstinência a Substâncias/fisiopatologia , Morfina/farmacologia , Neurônios/metabolismo , Núcleo Accumbens/metabolismo , Memória/fisiologia , Receptores de AMPA/metabolismo , Ratos , Dependência de Morfina/metabolismo , Tonsila do Cerebelo/metabolismo , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Vias Neurais/metabolismo , Córtex Pré-Frontal/metabolismo
3.
Am J Physiol Cell Physiol ; 326(1): C60-C73, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38009194

RESUMO

Radiotherapy has long been a main treatment option for nasopharyngeal carcinoma (NPC). However, during clinical treatment, NPC is prone to developing radioresistance, resulting in treatment failure. This study aims to examine the role of histone methylation in the induction of radioresistance. It was found that the radioresistance of NPC cells was related to the increase of the level of histone H3 lysine 27 trimethylation (H3K27me3). Treatment of cells with histone methyltransferase inhibitor GSK126 increased the radiosensitivity of NPC cells by triggering Bcl2 apoptosis regulator/BCL2-associated X, apoptosis regulator (Bcl2/BAX) signaling pathway. Bioinformatics analysis indicated that the expression of 2'-5'-oligoadenylate synthetase 1 (OAS1) was reduced in the radioresistant cells but increased in the GSK126-treated cells. Chromatin immunoprecipitation assay confirmed that the decrease of OAS1 expression in radioresistant cells was mainly due to the enrichment of H3K27me3 in its promoter region. Furthermore, downregulation of OAS1 reduced apoptosis due to the inhibition of Bcl2/BAX pathway after irradiation, while OAS1 overexpression increased radiosensitivity. Our findings revealed for the first time that the increase of H3K27me3 level was associated with the decrease of OAS1 expression, leading to the inhibition of apoptosis and ultimately contributing to the radioresistance of NPC cells. Moreover, the histone methyltransferase inhibitor GSK126 could overcome the radioresistance and thus might be a potential therapeutic strategy for NPC.NEW & NOTEWORTHY Our findings revealed for the first time that the increase of H3K27me3 level was associated with the decrease of OAS1 expression, leading to the inhibition of apoptosis and ultimately contributing to the radioresistance of NPC cells. Moreover, we demonstrated that the histone methyltransferase inhibitor GSK126 could be a promising therapeutic strategy for NPC by overcoming radioresistance, providing valuable insights into the clinical treatment of NPC.


Assuntos
Carcinoma , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Histonas/genética , Histonas/metabolismo , Carcinoma/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Histona Metiltransferases/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , 2',5'-Oligoadenilato Sintetase/metabolismo
4.
BMC Genomics ; 25(1): 68, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233753

RESUMO

BACKGROUND: Costaceae, commonly known as the spiral ginger family, consists of approximately 120 species distributed in the tropical regions of South America, Africa, and Southeast Asia, of which some species have important ornamental, medicinal and ecological values. Previous studies on the phylogenetic and taxonomic of Costaceae by using nuclear internal transcribed spacer (ITS) and chloroplast genome fragments data had low resolutions. Additionally, the structures, variations and molecular evolution of complete chloroplast genomes in Costaceae still remain unclear. Herein, a total of 13 complete chloroplast genomes of Costaceae including 8 newly sequenced and 5 from the NCBI GenBank database, representing all three distribution regions of this family, were comprehensively analyzed for comparative genomics and phylogenetic relationships. RESULT: The 13 complete chloroplast genomes of Costaceae possessed typical quadripartite structures with lengths from 166,360 to 168,966 bp, comprising a large single copy (LSC, 90,802 - 92,189 bp), a small single copy (SSC, 18,363 - 20,124 bp) and a pair of inverted repeats (IRs, 27,982 - 29,203 bp). These genomes coded 111 - 113 different genes, including 79 protein-coding genes, 4 rRNA genes and 28 - 30 tRNAs genes. The gene orders, gene contents, amino acid frequencies and codon usage within Costaceae were highly conservative, but several variations in intron loss, long repeats, simple sequence repeats (SSRs) and gene expansion on the IR/SC boundaries were also found among these 13 genomes. Comparative genomics within Costaceae identified five highly divergent regions including ndhF, ycf1-D2, ccsA-ndhD, rps15-ycf1-D2 and rpl16-exon2-rpl16-exon1. Five combined DNA regions (ycf1-D2 + ndhF, ccsA-ndhD + rps15-ycf1-D2, rps15-ycf1-D2 + rpl16-exon2-rpl16-exon1, ccsA-ndhD + rpl16-exon2-rpl16-exon1, and ccsA-ndhD + rps15-ycf1-D2 + rpl16-exon2-rpl16-exon1) could be used as potential markers for future phylogenetic analyses and species identification in Costaceae. Positive selection was found in eight protein-coding genes, including cemA, clpP, ndhA, ndhF, petB, psbD, rps12 and ycf1. Maximum likelihood and Bayesian phylogenetic trees using chloroplast genome sequences consistently revealed identical tree topologies with high supports between species of Costaceae. Three clades were divided within Costaceae, including the Asian clade, Costus clade and South American clade. Tapeinochilos was a sister of Hellenia, and Parahellenia was a sister to the cluster of Tapeinochilos + Hellenia with strong support in the Asian clade. The results of molecular dating showed that the crown age of Costaceae was about 30.5 Mya (95% HPD: 14.9 - 49.3 Mya), and then started to diverge into the Costus clade and Asian clade around 23.8 Mya (95% HPD: 10.1 - 41.5 Mya). The Asian clade diverged into Hellenia and Parahellenia at approximately 10.7 Mya (95% HPD: 3.5 - 25.1 Mya). CONCLUSION: The complete chloroplast genomes can resolve the phylogenetic relationships of Costaceae and provide new insights into genome structures, variations and evolution. The identified DNA divergent regions would be useful for species identification and phylogenetic inference in Costaceae.


Assuntos
Genoma de Cloroplastos , Filogenia , Teorema de Bayes , Genômica/métodos , DNA
5.
Biochem Biophys Res Commun ; 720: 150076, 2024 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-38772224

RESUMO

Chronic morphine withdrawal memory formation is a complex process influenced by various molecular mechanisms. In this study, we aimed to investigate the contributions of the basolateral amygdala (BLA) and complement component 1, q subcomponent-like 3 (C1QL3), a secreted and presynaptically targeted protein, to the formation of chronic morphine (repeat dosing of morphine) withdrawal memory using conditioned place aversion (CPA) and chemogenetic methods. We conducted experiments involving the inhibition of the BLA during naloxone-induced withdrawal to assess its impact on CPA scores, providing insights into the significance of the BLA in the chronic morphine memory formation process. We also examined changes in C1ql3/C1QL3 expression within the BLA following conditioning. Immunofluorescence analysis revealed the colocalization of C1QL3 and the G protein-coupled receptor, brain-specific angiogenesis inhibitor 3 (BAI3) in the BLA, supporting their involvement in synaptic development. Moreover, we downregulated C1QL3 expression in the BLA to investigate its role in chronic morphine withdrawal memory formation. Our findings revealed that BLA inhibition during naloxone-induced withdrawal led to a significant reduction in CPA scores, confirming the critical role of the BLA in this memory process. Additionally, the upregulation of C1ql3 expression within the BLA postconditioning suggested its participation in withdrawal memory formation. The colocalization of C1QL3 and BAI3 in the BLA further supported their involvement in synaptic development. Furthermore, downregulation of C1QL3 in the BLA effectively hindered chronic morphine withdrawal memory formation, emphasizing its pivotal role in this process. Notably, we identified postsynaptic density protein 95 (PSD95) as a potential downstream effector of C1QL3 during chronic morphine withdrawal memory formation. Blocking PSD95 led to a significant reduction in the CPA score, and it appeared that C1QL3 modulated the ubiquitination-mediated degradation of PSD95, resulting in decreased PSD95 protein levels. This study underscores the importance of the BLA, C1QL3 and PSD95 in chronic morphine withdrawal memory formation. It provides valuable insights into the underlying molecular mechanisms, emphasizing their significance in this intricate process.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Proteína 4 Homóloga a Disks-Large , Memória , Morfina , Síndrome de Abstinência a Substâncias , Animais , Morfina/farmacologia , Síndrome de Abstinência a Substâncias/metabolismo , Masculino , Camundongos , Memória/efeitos dos fármacos , Proteína 4 Homóloga a Disks-Large/metabolismo , Complexo Nuclear Basolateral da Amígdala/metabolismo , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Complemento C1q/metabolismo , Camundongos Endogâmicos C57BL , Naloxona/farmacologia
6.
Planta ; 260(3): 65, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073585

RESUMO

MAIN CONCLUSION: This study revealed the transcriptome-wide m6A methylation profile under drought stress and found that TaETC9 might regulate drought tolerance through mediating RNA methylation in wheat. Drought is one of the most destructive environmental constraints limiting crop growth and development. N6-methyladenosine (m6A) is a prevalent and important post-transcriptional modification in various eukaryotic RNA molecules, playing the crucial role in regulating drought response in plants. However, the significance of m6A in wheat (Triticum aestivum L.), particularly its involvment in drought response, remains underexplored. In this study, we investigated the transcriptome-wide m6A profile under drought stress using parallel m6A immunoprecipitation sequencing (MeRIP-seq). Totally, 4221 m6A peaks in 3733 m6A-modified genes were obtained, of which 373 methylated peaks exhibited differential expression between the control (CK) and drought-stressed treatments. These m6A loci were significantly enriched in proximity to stop codons and within the 3'-untranslated region. Integration of MeRIP-seq and RNA-seq revealed a positive correlation between m6A methylation and mRNA abundance and the genes displaying both differential methylation and expression were obtained. Finally, qRT-PCR analyses were further performed and the results found that the m6A-binding protein (TaETC9) showed significant up-regulation, while the m6A demethylase (TaALKBH10B) was significantly down-regulated under drought stress, contributing to increased m6A levels. Furthermore, the loss-of-function mutant of TaECT9 displayed significantly higher drought sensitivity compared to the wild type, highlighting its role in regulating drought tolerance. This study reported the first wheat m6A profile associated with drought stress, laying the groundwork for unraveling the potential role of RNA methylation in drought responses and enhancing stress tolerance in wheat through epigenetic approaches.


Assuntos
Adenosina , Secas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Transcriptoma , Triticum , Triticum/genética , Triticum/fisiologia , Metilação , Adenosina/análogos & derivados , Adenosina/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
New Phytol ; 242(5): 2115-2131, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358006

RESUMO

Drought is one of the major environmental constraints for wheat production world-wide. As the progenitor and genetic reservoir of common wheat, emmer wheat is considered as an invaluable gene pool for breeding drought-tolerant wheat. Combining GWAS and eGWAS analysis of 107 accessions, we identified 86 QTLs, 105 462 eQTLs as well as 68 eQTL hotspots associating with drought tolerance (DT) in emmer wheat. A complex regulatory network composed of 185 upstream regulator and 2432 downstream drought-responsive candidates was developed, of which TtOTS1 was found to play a negative effect in determining DT through affecting root development. This study sheds light on revealing the genetic basis underlying DT, which will provide the indispensable genes and germplasm resources for elite drought tolerance wheat improvement and breeding.


Assuntos
Resistência à Seca , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Triticum , Adaptação Fisiológica/genética , Resistência à Seca/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Polimorfismo de Nucleotídeo Único , Triticum/genética , Triticum/fisiologia
8.
Opt Express ; 32(12): 20471-20482, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859428

RESUMO

In this paper, we propose a novel and simple multi-channel broadband optical chaos generation scheme based on phase modulation and chirped fiber Bragg grating (CFBG). Firstly, phase modulation is introduced to generate more new frequency components to broaden the spectrum of the phase chaos. Meanwhile, the accumulated dispersion from CFBG distorts the intensity chaos, converts phase chaos to intensity chaos, and weakens the laser relaxation oscillation. This process would lead to energy redistribution in the power spectrum, effectively increasing the chaotic bandwidth. Then, the wavelength detuning between CFBG and the semiconductor laser is introduced to enhance the chaotic bandwidth further. The experiment results show that the 10 dB bandwidths of the five channels are up to 31.0 GHz, 34.3 GHz, 36.3 GHz, 40 GHz, and 40 GHz, respectively. Note that the maximum bandwidth of the PD in our experiment is limited to 40 GHz. In addition, the multi-channel chaotic signals obtained from the experiment system are used to generate multi-channel physical random numbers. After the post-processing operations, the total rate of five parallel high-speed physical random number generation channels is 4.64 Tbit/s (160 GSa/s × 5bit × 1 channel + 160 GSa/s × 6bit × 4 channels). As far as we know, this is the highest record of using external cavity feedback semiconductor lasers to generate random numbers, which has great potential to meet the security requirements of next-generation Tbit/s optical communication systems.

9.
Opt Express ; 32(2): 1123-1134, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297671

RESUMO

In real-world complex systems, heterogeneous components often interact in complex connection patterns and could be schematized by a formalism of multilayer network. In this work, the synchronization characteristics of multilayer network composed of semiconductor lasers (SLs) are investigated systematically. It is demonstrated that the interplay between different layers plays an important role on the synchronization patterns. We elucidate that the performance of cluster synchronization could be facilitated effectively with the introduction of disjoint layer symmetry into network topology. Intertwined stability of clusters from different layers could be decoupled into independent, and the parameter spaces for stable synchronization are extended significantly. The robustness of our proposed regulation scheme on operation parameters is numerically evaluated. Furthermore, the generality of presented theoretical results is validated in networks with more complex topology and multiple layers.

10.
Opt Lett ; 49(9): 2521-2524, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691759

RESUMO

Quantum key distribution allows secret key generation with information theoretical security. It can be realized with photonic integrated circuits to benefit the tiny footprints and the large-scale manufacturing capacity. Continuous-variable quantum key distribution is suitable for chip-based integration due to its compatibility with mature optical communication devices. However, the quantum signal power control compatible with the mature photonic integration process faces difficulties on stability, which limits the system performance and causes the overestimation of a secret key rate that opens practical security loopholes. Here, a highly stable chip-based quantum signal power control scheme based on a biased Mach-Zehnder interferometer structure is proposed, theoretically analyzed, and experimentally implemented with standard silicon photonic techniques. Simulations and experimental results show that the proposed scheme significantly improves the system stability, where the standard deviation of the secret key rate is suppressed by an order of magnitude compared with the system using traditional designs, showing a promising and practicable way to realize a highly stable continuous-variable quantum key distribution system on chip.

11.
Br J Dermatol ; 190(2): 199-206, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-37766469

RESUMO

BACKGROUND: Nodular melanoma (NM) is a challenge to diagnose early due to its rapid growth and more atypical clinical presentation, making it the largest contributor to melanoma mortality. OBJECTIVES: Our study aim was to perform a rare-variant allele (RVA) analysis of whole-exome sequencing of patients with NM and non-NM (minor allele frequency ≤ 1% non-Finnish European) for a set of 500 candidate genes potentially implicated in melanoma. METHODS: This study recruited 131 participants with NM and 194 with non-NM from South-east Queensland and patients with NM from Victoria to perform a comparative analysis of possible genetic differences or similarities between the two melanoma cohorts. RESULTS: Phenotypic analysis revealed that a majority of patients diagnosed with NM were older males with a higher frequency of fair skin and red hair than is seen in the general population. The distribution of common melanoma polygenic risk scores was similar in patients with NM and non-NM, with over 28% in the highest quantile of scores. There was also a similar frequency of carriage of familial/high-penetrant melanoma gene and loss-of-function variants. We identified 39 genes by filtering 500 candidate genes based on the greatest frequency in NM compared with non-NM cases. The genes with RVAs of greatest frequency in NM included PTCH1, ARID2 and GHR. Rare variants in the SMO gene, which interacts with PTCH1 as ligand and receptor, were also identified, providing evidence that the Hedgehog pathway may contribute to NM risk. There was a cumulative effect in carrying multiple rare variants in the NM-associated genes. A 14.8-fold increased ratio for NM compared with non-NM was seen when two RVAs of the 39 genes were carried by a patient. CONCLUSIONS: This study highlights the importance of considering frequency of RVA to identify those at risk of NM in addition to known high penetrance genes.


Assuntos
Melanoma , Neoplasias Cutâneas , Masculino , Humanos , Melanoma/genética , Proteínas Hedgehog , Neoplasias Cutâneas/genética , Fatores de Risco , Frequência do Gene , Predisposição Genética para Doença
12.
Ann Hematol ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347830

RESUMO

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a crucial treatment option for children with M2 subtype acute myeloid leukemia (AML). Human herpesvirus 6 (HHV-6) encephalitis following transplantation is a rare postoperative complication, with a poor prognosis and a high fatality rate in allo-HSCT recipients. In this report, a juvenile patient with AMLwas successfully treated after developing visual impairment as a result of HHV-6B encephalitis during allo-HSCT therapy. HHV-6 encephalitis-associated visual impairment after transplantation is rare, and clinical diagnosis and treatment are challenging, requiring more attention in the future.

13.
PLoS Biol ; 19(7): e3001355, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34319985

RESUMO

Sensing and response to environmental cues, such as pH and chloride (Cl-), is critical in enabling Mycobacterium tuberculosis (Mtb) colonization of its host. Utilizing a fluorescent reporter Mtb strain in a chemical screen, we have identified compounds that dysregulate Mtb response to high Cl- levels, with a subset of the hits also inhibiting Mtb growth in host macrophages. Structure-activity relationship studies on the hit compound "C6," or 2-(4-((2-(ethylthio)pyrimidin-5-yl)methyl)piperazin-1-yl)benzo[d]oxazole, demonstrated a correlation between compound perturbation of Mtb Cl- response and inhibition of bacterial growth in macrophages. C6 accumulated in both bacterial and host cells, and inhibited Mtb growth in cholesterol media, but not in rich media. Subsequent examination of the Cl- response of Mtb revealed an intriguing link with bacterial growth in cholesterol, with increased transcription of several Cl--responsive genes in the simultaneous presence of cholesterol and high external Cl- concentration, versus transcript levels observed during exposure to high external Cl- concentration alone. Strikingly, oral administration of C6 was able to inhibit Mtb growth in vivo in a C3HeB/FeJ murine infection model. Our work illustrates how Mtb response to environmental cues can intersect with its metabolism and be exploited in antitubercular drug discovery.


Assuntos
Antituberculosos/farmacologia , Desenvolvimento de Medicamentos , Mycobacterium tuberculosis/efeitos dos fármacos , Animais , Antituberculosos/química , Cloretos/metabolismo , Colesterol/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Macrófagos/microbiologia , Camundongos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/crescimento & desenvolvimento , Relação Estrutura-Atividade
14.
Connect Tissue Res ; 65(4): 304-312, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38922815

RESUMO

AIM: In this study, we aimed to establish a rat tooth movement model to assess miR-20's ability in enhancing the BMP2 signaling pathway and facilitate alveolar bone remodeling. METHOD: 60 male SD rats had nickel titanium spring devices placed between their left upper first molars and incisors, with the right side serving as the control. Forces were applied at varying durations (18h, 24h, 30h, 36h, 42h, 1d, 3d, 5d, 7d, 14d), and their bilateral maxillary molars and surrounding alveolar bones were retrieved for analysis. Fluorescent quantitative PCR was conducted to assess miR-20a, BMP2, Runx2, Bambi and Smad6 gene expression in alveolar bone, and western blot was performed to determine the protein levels of BMP2, Runx2, Bambi, and Smad6 after mechanical loading. RESULT: We successfully established an orthodontic tooth movement model in SD rats and revealed upregulated miR-20a expression and significantly increased BMP2 and Runx2 gene expression and protein synthesis in alveolar bone during molar tooth movement. Although Bambi and Smad6 gene expression did not significantly increase, their protein synthesis was found to decrease significantly. CONCLUSION: MiR-20a was found to be involved in rat tooth movement model alveolar bone remodeling, wherein it promoted remodeling by reducing Bambi and Smad6 protein synthesis through the BMP2 signaling pathway.


Assuntos
Proteína Morfogenética Óssea 2 , MicroRNAs , Ratos Sprague-Dawley , Transdução de Sinais , Técnicas de Movimentação Dentária , Animais , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 2/genética , Masculino , MicroRNAs/metabolismo , MicroRNAs/genética , Ratos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Processo Alveolar/metabolismo , Processo Alveolar/patologia , Regulação da Expressão Gênica
15.
J Org Chem ; 89(17): 11975-11982, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39163632

RESUMO

Herein, we developed a ligand-promoted Rh(III)-catalyzed C(sp3)-H thiolation of 8-methylquinolines. The effect of ligands on improving the activity of the catalytic centers has been studied in detail and proven to be significant. Various substituents are well tolerated under this reaction condition to provide potential precursors for organic synthesis. The mechanistic study suggests that the reaction may proceed through a five-membered rhodacycle intermediate via thiolation twice.

16.
Org Biomol Chem ; 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39480528

RESUMO

A K2CO3-promoted tandem ring-opening/ring-closing of N-alkynyl-2-oxazolidinones has been described, affording 2-oxazolines in 42-99% yields without column chromatography isolation. This operationally simple reaction proceeds under ambient conditions without a transition-metal catalyst and an external oxidant and can be applied for the late-stage functionalization of biologically active compounds.

17.
J Fluoresc ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512429

RESUMO

The detection and removal of Pb2+ is of utmost importance for environmental protection and human health due to its toxicity, persistent pollution, and bioaccumulation effects. To address the limitations associated with organic small molecule-based fluorescence probes such as poor water solubility and single functionality in detecting Pb2+, a fluorescence probe based on halloysite nanotubes was developed. This probe not only enables specific, rapid, and reliable detection of Pb2+ but also facilitates efficient removal of it from water. The development of this bifunctional fluorescent probe provides a valuable insight for designing more advanced probes targeting heavy metal ions.

18.
Phys Chem Chem Phys ; 26(38): 25048-25056, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39301688

RESUMO

Vanadate phosphors include [VO4] tetrahedra with Td symmetry. Due to the charge transfer (CT) between V5+-O2-, the phosphor with [VO4] tetrahedra exhibits strong emission in the visible region and can effectively absorb ultraviolet (UV) light. Garnet structured vanadate phosphors have attracted much attention due to their easily controllable composition. In this paper, we successfully prepared phosphors with high quantum efficiency. The lattice structure and luminescent properties of the samples were studied in detail. Vanadate garnet phosphors have the same structure. The phosphors exhibit broadband emission peaks under 266 nm and 355 nm near-ultraviolet (UV) excitation, emitting bright greenish-white and yellowish-white light. The emission wavelength of the phosphor is red-shifted. The phosphors exhibit high internal quantum efficiency (IQE) for the NaSr2Mg2V3O12 and KCa2Mg2V3O12 samples. In this paper, the structure and luminescence characteristics of greenish-white-emitting and yellowish-white-emitting vanadate phosphors with high quantum efficiency are investigated.

19.
Phys Chem Chem Phys ; 26(9): 7343-7350, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38369913

RESUMO

Two-dimensional (2D) materials are an excellent platform for surface-enhanced Raman spectroscopy (SERS). For ReS2, the Raman enhancement effect can be highly improved through the dipole-dipole interactions and synergistic resonance effects in the phase-engineering ReS2 films. However, the performance of the substrate can be improved further through regulating the electronic interaction between the ReS2 and probe molecules. Herein, a dynamic coulomb repulsion strategy is proposed to trigger an electronic state redistribution by asymmetric electrostatic interactions. With the phase-engineering ReS2/graphene heterostructure as a prototype, under laser excitation, the generated hot electrons in graphene and ReS2 can repel each other due to Coulomb interaction, which breaks the symmetrical distribution of hot electrons in ReS2, and increases the electronic concentration at the interface between ReS2 and the probe molecule. With R6G as the probe molecule, the asymmetric electron distribution and synergistic resonance effects on their interface improve the limit of detection to 10-12 M with an EF of 2.15 × 108. Meanwhile, the heterostructure also shows good uniformity, stability as well as unique anisotropy. This strategy can be generalized to other 2D heterostructures to obtain the ultrasensitive SERS substrates.

20.
Phys Chem Chem Phys ; 26(32): 21832-21840, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39102283

RESUMO

Self-activated phosphors have attracted considerable attention due to their low synthesis temperature, high excitation threshold, and broad emission spectrum. And self-activated tungstate phosphors are distinguished by their low cost and stable chemical properties. Generally, it is difficult to observe luminescence from tungstate phosphors at room temperature. Furthermore, blue-emitting tungstate phosphors with high quantum efficiency are rarely reported. In this study, we succeeded in discovering high quantum-efficiency bluish-white-emitting Li2(MgxZn1-x)2W2O9 phosphors and investigating their detailed crystal structures. Upon near-ultraviolet excitation at 266 nm, these phosphors exhibit a broadband emission peak. The red shift of emission is slight with increasing Zn content in Li2(MgxZn1-x)2W2O9. A highly compact octahedral [WO6] unit is observed in the Li2(MgxZn1-x)2W2O9 phosphors. The phosphors exhibit high internal quantum efficiencies (IQEs) of 68.70% (M = Mg), 43.90% (M = Mg0.5Zn0.5), and 22.90% (M = Zn), respectively. This study provides a bluish-white-emitting tungstate phosphor with high quantum efficiency.

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