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1.
Curr Issues Mol Biol ; 46(3): 2251-2262, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38534760

RESUMO

Prostate cancer accounts for 14% of male cancer-related fatalities in the UK. Given the challenges associated with hormone-based therapies in the context of androgen-independent prostate cancer, there is an imperative need for research into anticancer drugs. N0821, a peptide belonging to the Trp-Arg dense region and derived from the homologous region of various bee species, shows substantial potential for an anticancer effect. Both MTT assays and 3D spheroid assays were conducted to substantiate its antiproliferation potential and strongly indicated the antiproliferation effect of N0820 (WWWWRWWRKI) and N0821 (YWWWWRWWRKI). Notably, the mechanism underlying this effect is related to the downregulation of CCNA2 and the upregulation of CCNE1. Cell cycle arrest results from the reduction of CCNA2 in the S/G2 phase, leading to the accumulation of CCNE1. Our peptides were predicted to make an α-helix structure. This can act as an ion channel in the cell membrane. Therefore, we analyzed genes implicated in the influx of calcium ions into the mitochondria. Trp-Arg dense-region peptides are known for their antibacterial properties in targeting cell membranes, making the development of resistance less likely. Hence, further research in this area is essential and promising.

2.
Brain Behav Immun ; 115: 295-307, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37884161

RESUMO

GV1001 protects neural cells from amyloid-ß (Aß) toxicity and other stressors in in vitro studies and demonstrates clinically beneficial effects in patients with moderate to severe Alzheimer's disease (AD). Here, we investigated the protective effects and mechanism of action of GV1001 in triple transgenic AD (3xTg-AD) mice. We found that GV1001 improved memory and cognition in middle- and old-aged 3xTg-AD mice. Additionally, it reduced Aß oligomer and phospho-tau (Ser202 and Thr205) levels in the brain, and mitigated neuroinflammation by promoting a neuroprotective microglial and astrocyte phenotype while diminishing the neurotoxic ones. In vitro, GV1001 bound to gonadotropin releasing hormone receptors (GnRHRs) with high affinity. Levels of cyclic adenosine monophosphate, a direct downstream effector of activated GnRHRs, increased after GV1001 treatment. Furthermore, inhibition of GnRHRs blocked GV1001-induced effects. Thus, GV1001 might improve cognitive and memory functions of 3xTg-AD mice by suppressing neuroinflammation and reducing Aß oligomers levels and phospho-tau by activating GnRHRs and their downstream signaling pathways.


Assuntos
Doença de Alzheimer , Humanos , Camundongos , Animais , Pessoa de Meia-Idade , Idoso , Doença de Alzheimer/metabolismo , Camundongos Transgênicos , Receptores LHRH , Doenças Neuroinflamatórias , Proteínas tau/genética , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Hormônio Liberador de Gonadotropina , Modelos Animais de Doenças
3.
Org Biomol Chem ; 22(21): 4309-4317, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38717394

RESUMO

Methods of selectively synthesizing diorganyl diselenides (R-Se-Se-R) without using harmful reducing agents are presented. We optimized the reaction conditions for the selective formation of the diselenide dianion (Se22-) and the corresponding diorganyl diselenides using basic reagents (e.g., KOH), while suppressing the formation of side products, such as diorganyl selenides (R-Se-R) or multiselenides (R-Sen-R; n ≥ 3). Furthermore, we have suggested and examined the reaction pathways responsible for the formation of the desired diorganyl diselenides 1 and side products 2 and 3. Consequently, the selective synthesis of diverse diorganyl diselenides was achieved with modest to excellent yields (33-99%) using various organyl halides under optimized conditions. The results provide a practical and efficient synthetic method for diorganyl diselenides as a representative class of organoselenium compounds.

4.
Mol Cancer ; 22(1): 63, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36991428

RESUMO

BACKGROUND: Although metastasis is the foremost cause of cancer-related death, a specialized mechanism that reprograms anchorage dependency of solid tumor cells into circulating tumor cells (CTCs) during metastatic dissemination remains a critical area of challenge. METHODS: We analyzed blood cell-specific transcripts and selected key Adherent-to-Suspension Transition (AST) factors that are competent to reprogram anchorage dependency of adherent cells into suspension cells in an inducible and reversible manner. The mechanisms of AST were evaluated by a series of in vitro and in vivo assays. Paired samples of primary tumors, CTCs, and metastatic tumors were collected from breast cancer and melanoma mouse xenograft models and patients with de novo metastasis. Analyses of single-cell RNA sequencing (scRNA-seq) and tissue staining were performed to validate the role of AST factors in CTCs. Loss-of-function experiments were performed by shRNA knockdown, gene editing, and pharmacological inhibition to block metastasis and prolong survival. RESULTS: We discovered a biological phenomenon referred to as AST that reprograms adherent cells into suspension cells via defined hematopoietic transcriptional regulators, which are hijacked by solid tumor cells to disseminate into CTCs. Induction of AST in adherent cells 1) suppress global integrin/ECM gene expression via Hippo-YAP/TEAD inhibition to evoke spontaneous cell-matrix dissociation and 2) upregulate globin genes that prevent oxidative stress to acquire anoikis resistance, in the absence of lineage differentiation. During dissemination, we uncover the critical roles of AST factors in CTCs derived from patients with de novo metastasis and mouse models. Pharmacological blockade of AST factors via thalidomide derivatives in breast cancer and melanoma cells abrogated CTC formation and suppressed lung metastases without affecting the primary tumor growth. CONCLUSION: We demonstrate that suspension cells can directly arise from adherent cells by the addition of defined hematopoietic factors that confer metastatic traits. Furthermore, our findings expand the prevailing cancer treatment paradigm toward direct intervention within the metastatic spread of cancer.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Melanoma , Células Neoplásicas Circulantes , Camundongos , Animais , Humanos , Feminino , Linhagem Celular Tumoral , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Melanoma/metabolismo , Neoplasias Pulmonares/patologia , Metástase Neoplásica
5.
Mol Psychiatry ; 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35902630

RESUMO

There is a compelling need to develop disease-modifying therapies for Alzheimer's disease (AD), the most common neuro-degenerative disorder. Together with recent progress in vector development for efficiently targeting the central nervous system, gene therapy has been suggested as a potential therapeutic modality to overcome the limited delivery of conventional types of drugs to and within the damaged brain. In addition, given increasing evidence of the strong link between glia and AD pathophysiology, therapeutic targets have been moving toward those addressing glial cell pathology. Nurr1 and Foxa2 are transcription/epigenetic regulators that have been reported to cooperatively regulate inflammatory and neurotrophic response in glial cells. In this study, we tested the therapeutic potential of Nurr1 and Foxa2 gene delivery to treat AD symptoms and pathologies. A series of functional, histologic, and transcriptome analyses revealed that the combined expression of Nurr1 and Foxa2 substantially ameliorated AD-associated amyloid ß and Tau proteinopathy, cell senescence, synaptic loss, and neuro-inflammation in multiple in vitro and in vivo AD models. Intra-cranial delivery of Nurr1 and Foxa2 genes using adeno-associated virus (AAV) serotype 9 improved the memory and cognitive function of AD model mice. The therapeutic benefits of gene delivery were attained mainly by correcting pathologic glial function. These findings collectively indicate that AAV9-mediated Nurr1 and Foxa2 gene transfer could be an effective disease-modifying therapy for AD.

6.
Microbiol Immunol ; 67(10): 456-467, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37525428

RESUMO

Defensins and inflammation are innate immune barriers of the body against infectious pathogens. Searching for a compound that can inhibit infectious diseases by affecting human ß-defensin (HBD) and proinflammatory cytokines is the new trend in research to control bacterial infection. The aim of this study is to provide a natural compound, Filipendula glaberrima Nakai extract (FGE), which is able to induce the expression of an antimicrobial defensin as well as reduce inflammation. FGE induced the expression of HBD2 and HBD3 through activating both p38 and NF-κB signaling pathways. Furthermore, FGE inhibited the expression of TNF-α and IL-6 via p38 and NF-κB pathways in Staphylococcus aureus-stimulated THP1 cells. Injection of FGE alleviated cutaneous erythema and swelling caused by S. aureus injection in mice ears. Taken together, FGE could reduce bacterial infection by inducing the expression of defensin and anti-inflammatory activity.


Assuntos
Infecções Bacterianas , Filipendula , beta-Defensinas , Animais , Camundongos , Humanos , NF-kappa B/metabolismo , Células Cultivadas , Staphylococcus aureus , beta-Defensinas/metabolismo , Inflamação/tratamento farmacológico
7.
J Enzyme Inhib Med Chem ; 38(1): 2191164, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36950944

RESUMO

Prions are infectious protein particles known to cause prion diseases. The biochemical entity of the pathogen is the misfolded prion protein (PrPSc) that forms insoluble amyloids to impair brain function. PrPSc interacts with the non-pathogenic, cellular prion protein (PrPC) and facilitates conversion into a nascent misfolded isoform. Several small molecules have been reported to inhibit the aggregation of PrPSc but no pharmacological intervention was well established thus far. We, here, report that acylthiosemicarbazides inhibit the prion aggregation. Compounds 7x and 7y showed almost perfect inhibition (EC50 = 5 µM) in prion aggregation formation assay. The activity was further confirmed by atomic force microscopy, semi-denaturing detergent agarose gel electrophoresis and real-time quaking induced conversion assay (EC50 = 0.9 and 2.8 µM, respectively). These compounds also disaggregated pre-existing aggregates in vitro and one of them decreased the level of PrPSc in cultured cells with permanent prion infection, suggesting their potential as a treatment platform. In conclusion, hydroxy-2-naphthoylthiosemicarbazides can be an excellent scaffold for the discovery of anti-prion therapeutics.


Assuntos
Doenças Priônicas , Príons , Humanos , Príons/metabolismo , Proteínas Priônicas/metabolismo , Encéfalo , Doenças Priônicas/tratamento farmacológico , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Células Cultivadas
8.
Nano Lett ; 22(5): 2038-2047, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226507

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory disease associated with unbalanced immune responses in skin tissue. Although steroid drugs and antihistamines are generally used to treat AD, continuous administration causes multiple side effects. High oxidative stress derived from reactive oxygen species (ROS) has been implicated in the pathogenesis of AD. A high level of ROS promotes the release of pro-inflammatory cytokines and T-cell differentiation, resulting in the onset and deterioration of AD. Here, we report a therapeutic hydrogel patch suppressing the high oxidative stress generated in AD lesions. The hydrogel embedded with ROS-scavenging ceria nanoparticles leads to the decrease of both extracellular and intracellular ROS and exhibits cytoprotective effects in a highly oxidative condition. AD-induced mouse model studies show enhanced therapeutic outcomes, including a decrease in the epidermal thickness and levels of AD-associated immunological biomarkers. These findings indicate that a ROS-scavenging hydrogel could be a promising therapeutic hydrogel patch for treating and managing AD.


Assuntos
Dermatite Atópica , Animais , Citocinas/farmacologia , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Camundongos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Pele
9.
J Environ Manage ; 335: 117493, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36822047

RESUMO

Despite the identification of numerous bioplastic-degrading bacteria, the inconsistent rate of bioplastic degradation under differing cultivation conditions limits the intercomparison of results on biodegradation kinetics. In this study, we isolated a poly (Ɛ-caprolactone) (PCL)-degrading bacterium from a plastic-contaminated landfill and determined the principle-based biodegradation kinetics in a confined model system of varying cultivation conditions. Bacterial degradation of PCL films synthesized by different polymer number average molecular weights (Mn) and concentrations (% w/v) was investigated using both solid and liquid media at various temperatures. As a result, the most active gram-negative bacterial strain at ambient temperature (28 °C), designated CY2-9, was identified as Aquabacterium sp. Based on 16 S rRNA gene analysis. A clear zone around the bacterial colony was apparently exhibited during solid cultivation, and the diameter sizes increased with incubation time. During biodegradation processes in the PCL film, the thermal stability declined (determined by TGA; weight changes at critical temperature), whereas the crystalline proportion increased (determined by DSC; phase transition with temperature increment), implying preferential degradation of the amorphous region in the polymer structure. The surface morphologies (determined by SEM; electron optical system) were gradually hydrolyzed, creating destruction patterns as well as alterations in functional groups on film surfaces (determined by FT-IR; infrared spectrum of absorption or emission). In the kinetic study based on the weight loss of the PCL film (4.5 × 104 Da, 1% w/v), ∼1.5 (>±0.1) × 10-1 day-1 was obtained from linear regression for both solid and liquid media cultivation at 28 °C. The biodegradation efficiencies increased proportionally by a factor of 2.6-7.9, depending on the lower polymer number average molecular weight and lower concentration. Overall, our results are useful for measuring and/or predicting the degradation rates of PCL films by microorganisms in natural environments.


Assuntos
Plásticos , Poliésteres , Poliésteres/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Polímeros , Bactérias/metabolismo
10.
Molecules ; 28(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36985716

RESUMO

Both defensin and inflammation are part of the human innate immune system that responds rapidly to pathogens. The combination of defensins with pro- or anti-inflammatory effects can be a potential research direction for the treatment of infection by pathogens. This study aimed to identify whether MSF (Miracle Synergy material made using Filipendula glaberrima), a probiotic lysate of Filipendula glaberrima extracts fermented with Lactiplantibacillus plantarum K8, activates the expression of human ß-defensin (HBD2 and HBD3) to protect the host against pathogens and inhibit inflammation caused by S. aureus, in vitro with Western blot analysis, qRT-PCR and in vivo studies with a mouse model were used to evaluate the effects of MSF. The MSF treatment induced HBD2 and HBD3 expression via the p38 and NF-κB pathways. Furthermore, MSF treatment significantly reduced the expression of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, and IL-8), also through p38 and NF-κB in S. aureus-induced inflammatory condition. MSF treatment remarkably reduced erythema in mice ears caused by the injection of S. aureus, while K8 lysate treatment did not initiate a strong recovery. Taken together, MSF induced the expression of HBD2 and HDB3 and activated anti-inflammatory activity more than the probiotic lysates of L. plantarum K8. These findings show that MSF is a potential defensin inducer and anti-inflammatory agent.


Assuntos
NF-kappa B , beta-Defensinas , Animais , Camundongos , Humanos , NF-kappa B/metabolismo , beta-Defensinas/metabolismo , Peptídeos Antimicrobianos , Staphylococcus aureus , Células Cultivadas , Transdução de Sinais , Inflamação/tratamento farmacológico
11.
Hepatology ; 74(4): 2170-2185, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33932306

RESUMO

BACKGROUND AND AIMS: The important roles of glutamate and metabotropic glutamate receptor 5 (mGluR5) in HSCs have recently been reported in various liver diseases; however, the mechanism linking the glutamine/glutamate metabolism and mGluR5 in liver fibrosis remains unclear. Here, we report that mGluR5 activation in natural killer (NK) cells attenuates liver fibrosis through increased cytotoxicity and interferon-γ (IFN-γ) production in both mice and humans. APPROACH AND RESULTS: Following 2-week injection of carbon tetrachloride (CCl4 ) or 5-week methionine-deficient and choline-deficient diet, liver fibrosis was more aggravated in mGluR5 knockout mice with significantly decreased frequency of NK cells compared with wild-type mice. Consistently, NK cell-specific mGluR5 knockout mice had aggravated CCl4 -induced liver fibrosis with decreased production of IFN-γ. Conversely, in vitro activation of mGluR5 in NK cells significantly increased the expression of anti-fibrosis-related genes including Ifng, Prf1 (perforin), and Klrk1 (killer cell lectin like receptor K1) and the production of IFN-γ through the mitogen-activated extracellular signal-regulated kinase/extracellular signal-related kinase pathway, contributing to the increased cytotoxicity against activated HSCs. However, we found that the uptake of glutamate was increased in activated HSCs, resulting in shortage of extracellular glutamate and reduced stimulation of mGluR5 in NK cells. Consequently, this could enable HSCs to evade NK cell cytotoxicity in advanced liver fibrosis. In vivo, pharmacologic activation of mGluR5 accelerated CCl4 -induced liver fibrosis regression by restoring NK cell cytotoxicity. In humans, mGluR5 activation enhanced the cytotoxicity of NK cells isolated from healthy donors, but not from patients with cirrhosis with significantly reduced mGluR5 expression in NK cells. CONCLUSIONS: mGluR5 plays important roles in attenuating liver fibrosis by augmenting NK cell cytotoxicity, which could be used as a potential therapeutic target for liver fibrosis.


Assuntos
Células Estreladas do Fígado/fisiologia , Interferon gama/imunologia , Cirrose Hepática , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Animais , Células Cultivadas , Citotoxicidade Imunológica/imunologia , Modelos Animais de Doenças , Descoberta de Drogas , Humanos , Células Matadoras Naturais/fisiologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos
12.
Nanotechnology ; 34(3)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36223734

RESUMO

Sn is the one of the materials that can be used for next generation extreme ultraviolet (EUV) mask material having a high absorption coefficient and, for the fabrication of the next generation EUV mask, a precise etching of Sn is required. In this study, the atomic layer etching (ALE) process was performed for the precise etch thickness control and low damage etching of Sn by the formation SnHxClycompounds on the Sn surface using with H and Cl radicals during the adsorption step and by the removal of the compound using Ar+ions with a controlled energy during the desorption step. Through this process, optimized ALE conditions with different H/Cl radical combinations that can etch Sn at ∼2.6 Šcycle-1were identified with a high etch selectivity over Ru which can be used as the capping layer of the EUV mask. In addition, it was confirmed that not only the Sn but also Ru showed almost no physical and chemical damage during the Sn ALE process.

13.
Curr Microbiol ; 79(11): 340, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209171

RESUMO

Strain KSB-15 T was isolated from an orchard soil that had been contaminated with the insecticide dichlorodiphenyltrichloroethane for about 60 years. The 16S rRNA gene sequence of this strain showed the highest sequence similarities with those of Oleiharenicola alkalitolerans NVTT (95.3%), Opitutus terrae PB90-1 T (94.8%), and Oleiharenicola lentus TWA-58 T (94.7%) among type strains, which are members of the family Opitutaceae within the phylum Verrucomicrobia. Strain KSB-15 T was an obligate aerobe, Gram-negative, non-motile, coccoid or short rod with the cellular dimensions of 0.37-0.62 µm width and 0.43-0.72 µm length. The strain grew at temperatures between 15-37 °C (optimum, 25 °C), at a pH range of 5.0-11.0 (optimum, pH 6.0), and at a NaCl concentration of 0-3% (w/v) (optimum, 0%). It contained menaquinone-7 (MK-7) as the major isoprenoid quinone (94.1%), and iso-C15:0 (34.9%) and anteiso-C15:0 (29.0%) as the two major fatty acids. The genome of strain KSB-15 T was composed of one chromosome with a total size of 4,320,198 bp, a G + C content of 64.3%, 3,393 coding genes (CDS), 14 pseudogenes, and 52 RNA genes. The OrthoANIu values, In silico DDH values and average amino acid identities between strain KSB-15 T and the members of the family Opitutaceae were 71.6 ~ 73.0%, 19.0 ~ 19.9%, and 55.9 ~ 62.0%, respectively. On the basis of our polyphasic taxonomic study, we conclude that strain KSB-15 T should be classified as a novel genus of the family Opitutaceae, for which the name Horticcoccus luteus gen. nov., sp. nov. is proposed.The type strain is KSB-15 T (= KACC 22271 T = DSM 113638 T).


Assuntos
DDT , Inseticidas , Aminoácidos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Filogenia , Quinonas , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio , Solo , Terpenos , Verrucomicrobia/genética , Vitamina K 2/química
14.
J Korean Med Sci ; 37(7): e52, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35191229

RESUMO

Acute transverse myelitis (ATM) has been reported as rare complication of vaccination. Herein, we report 2 cases of ATM after the administration of an mRNA vaccine for coronavirus disease 2019 (COVID-19). The first one is an 81-year-old man who received the BNT162b2 vaccine. He presented with bilateral hand weakness. Spine magnetic resonance imaging (MRI) showed high signal intensity from the C1 to C3 vertebrae. The second is a 23-year-old woman who received the BNT162b2 vaccine and experienced tingling in her legs. Spine MRI showed a high signal intensity lesion at the conus medullaris. These patients were treated with intravenous methylprednisolone and their symptoms improved slightly. Careful follow-up is needed to identify adverse events after the administration of mRNA vaccines for COVID-19.


Assuntos
Vacina BNT162/efeitos adversos , Mãos/fisiopatologia , Perna (Membro)/fisiopatologia , Mielite Transversa/patologia , Medula Espinal/fisiopatologia , Vacinação/efeitos adversos , Idoso de 80 Anos ou mais , Vacina BNT162/imunologia , COVID-19/imunologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Mielite Transversa/diagnóstico , Mielite Transversa/tratamento farmacológico , SARS-CoV-2/imunologia , Coluna Vertebral/diagnóstico por imagem , Adulto Jovem
15.
Sensors (Basel) ; 22(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35632228

RESUMO

The 5G networks aim to realize a massive Internet of Things (IoT) environment with low latency. IoT devices with weak security can cause Tbps-level Distributed Denial of Service (DDoS) attacks on 5G mobile networks. Therefore, interest in automatic network intrusion detection using machine learning (ML) technology in 5G networks is increasing. ML-based DDoS attack detection in a 5G environment should provide ultra-low latency. To this end, utilizing a feature-selection process that reduces computational complexity and improves performance by identifying features important for learning in large datasets is possible. Existing ML-based DDoS detection technology mostly focuses on DDoS detection learning models on the wired Internet. In addition, studies on feature engineering related to 5G traffic are relatively insufficient. Therefore, this study performed feature selection experiments to reduce the time complexity of detecting and analyzing large-capacity DDoS attacks in real time based on ML in a 5G core network environment. The results of the experiment showed that the performance was maintained and improved when the feature selection process was used. In particular, as the size of the dataset increased, the difference in time complexity increased rapidly. The experiments show that the real-time detection of large-scale DDoS attacks in 5G core networks is possible using the feature selection process. This demonstrates the importance of the feature selection process for removing noisy features before training and detection. As this study conducted a feature study to detect network traffic passing through the 5G core with low latency using ML, it is expected to contribute to improving the performance of the 5G network DDoS attack automation detection technology using AI technology.


Assuntos
Internet das Coisas , Aprendizado de Máquina
16.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558124

RESUMO

Studies on the selective synthetic method for dialkyl ditellurides 1, a representative class of organyl tellurium compounds, were presented. Considering the difficulty in conducting previous harsh reactions and in suppressing the formation of dialkyl tellurides 2 as side products, we optimized reaction conditions for selective syntheses of sodium ditelluride and the corresponding dialkyl ditellurides 1. We reduced tellurium to sodium ditelluride by using NaBH4 and subsequently, treated the obtained sodium ditelluride with alkyl halides (RX) to give the target compounds 1. Consequently, by applying various alkyl halides (RX) we achieved the selective syntheses of dialkyl ditellurides 1 (13 examples with 4 new compounds) in modest to good yields. We also suggested the mechanistic pathways to dialkyl ditellurides 1.


Assuntos
Telúrio
17.
Molecules ; 27(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36235301

RESUMO

The syntheses of novel 1-acyloxyindole compounds 1 and the investigations on reaction pathways are presented. Nitro ketoester substrate 2, obtained in a two-step synthetic process, underwent reduction, intramolecular addition, nucleophilic 1,5-addition, and acylation to afford 1-acyloxyindoles 1 in one pot. Based on the systematic studies, we established the optimized reaction conditions for 1 focusing on the final acylation step of the intermediate 1-hydroxyindole 8. With the optimized conditions, we succeeded in synthesizing 21 examples of new 1-acyloxyindole derivatives 1 in modest yields (Y = 24 - 35%). Among the 1-acyloxyindole compounds, 1-acetoxyindole compounds 1x were generally unstable, and their yields were relatively lower than the other 1-acyloxyindoles. We expect that a bulkier alkyl or aromatic group on R2 could stabilize the 1-acyloxyindole compounds. Significantly, one-pot reactions of a four-step sequence successfully generated compounds 1 that are all new and might be difficult to be synthesized otherwise.


Assuntos
Estrutura Molecular , Acilação
18.
Molecules ; 27(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36014475

RESUMO

The studies on the selective synthesis of dialkyl selenide compounds 1 were presented. Overcoming the complexity and difficulty of selenides (R-Se-R) and/or multiselenides (R-Sen-R; n ≥ 2), we aimed to optimize the reaction condition for the tolerable preparation of sodium selenide (Na2Se) by reducing Se with NaBH4, and then to achieve selective syntheses of dialkyl selenides 1 by subsequently treating the obtained sodium selenide with alkyl halides (RX). Consequently, various dialkyl selenides 1 were efficiently synthesized in good-to-moderate yields. The investigations on reaction pathways and solvent studies were also described.


Assuntos
Compostos de Selênio , Solventes
19.
Environ Geochem Health ; 44(3): 925-932, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34120301

RESUMO

Dimethylmonothioarsinic acid (DMMTA(V)) and dimethyldithioarsinic acid (DMDTA(V)), which are commonly found in landfill leachate and pore water of rice paddy soil, have attracted considerable attention for their high toxicity. This study aims to evaluate the behavior and potential risks of DMMTA(V) and DMDTA(V) in the environment by conducting an equilibrium sorption test using 2-line ferrihydrite and acute toxicity (immobilization) test using Daphnia magna. The overall maximum sorption capacity (qm) derived by the Langmuir isotherm model showed an increase in the order of inorganic arsenate (As(V)) > dimethylarsinic acid (DMA(V)) > DMMTA(V) > DMDTA(V), which was likely due to steric hindrance due to the presence of methyl and thiol groups. Moreover, DMMTA(V) and DMDTA(V) showed no or negligible change in qm with pH change, while qm decreased rapidly with increasing pH in As(V) and DMA(V). The 50% inhibition concentrations (IC50) for As(V), DMA(V), DMMTA(V), and DMDTA(V), which were measured after 48 h exposure to D. magna, were 9.5, > 30, 1.7, and 6.5 mg/L, respectively. Overall, the results demonstrated that DMMTA(V) and DMDTA(V) have high mobility and eco-toxicity in the environment and that methylated thioarsenicals should be accurately monitored and controlled.


Assuntos
Arsenicais , Ácido Cacodílico , Animais , Ácido Cacodílico/análogos & derivados , Ácido Cacodílico/toxicidade , Daphnia , Compostos Férricos
20.
Hepatology ; 72(2): 609-625, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31849082

RESUMO

BACKGROUND AND AIMS: Mitochondrial double-stranded RNA (mtdsRNA) and its innate immune responses have been reported previously; however, mtdsRNA generation and its effects on alcohol-associated liver disease (ALD) remain unclear. Here, we report that hepatic mtdsRNA stimulates toll-like receptor 3 (TLR3) in Kupffer cells through the exosome (Exo) to enhance interleukin (IL)-17A (IL-17A) production in ALD. APPROACH AND RESULTS: Following binge ethanol (EtOH) drinking, IL-17A production primarily increased in γδ T cells of wild-type (WT) mice, whereas the production of IL-17A was mainly facilitated by CD4+ T cells in acute-on-chronic EtOH consumption. These were not observed in TLR3 knockout (KO) or Kupffer cell-depleted WT mice. The expression of polynucleotide phosphorylase, an mtdsRNA-restricting enzyme, was significantly decreased in EtOH-exposed livers and hepatocytes of WT mice. Immunostaining revealed that mtdsRNA colocalized with the mitochondria in EtOH-treated hepatocytes from WT mice and healthy humans. Bioanalyzer analysis revealed that small-sized RNAs were enriched in EtOH-treated Exos (EtOH-Exos) rather than EtOH-treated microvesicles in hepatocytes of WT mice and humans. Quantitative real-time PCR and RNA sequencing analyses indicated that mRNA expression of mitochondrial genes encoded by heavy and light strands was robustly increased in EtOH-Exos from mice and humans. After direct treatment with EtOH-Exos, IL-1ß expression was significantly increased in WT Kupffer cells but not in TLR3 KO Kupffer cells, augmenting IL-17A production of γδ T cells in mice and humans. CONCLUSIONS: EtOH-mediated generation of mtdsRNA contributes to TLR3 activation in Kupffer cells through exosomal delivery. Consequently, increased IL-1ß expression in Kupffer cells triggers IL-17A production in γδ T cells at the early stage that may accelerate IL-17A expression in CD4+ T cells in the later stage of ALD. Therefore, mtdsRNA and TLR3 may function as therapeutic targets in ALD.


Assuntos
Exossomos/genética , Interleucina-17/biossíntese , Células de Kupffer/metabolismo , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/metabolismo , RNA de Cadeia Dupla/fisiologia , RNA Mitocondrial/fisiologia , Receptor 3 Toll-Like/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
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