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1.
J Ethnopharmacol ; 333: 118407, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38824979

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Taohong Siwu Decoction (TSD), a classic traditional Chinese medicine formula, is used for the treatment of vascular diseases, including vascular dementia (VD). However, the mechanisms remain unclear. AIM OF STUDY: This study aimed to investigate whether TSD has a positive effect on cognitive impairment in VD rats and to confirm that the mechanism of action is related to the Endoplasmic Reticulum stress (ERs) and cell apoptosis signaling pathway. MATERIALS AND METHODS: A total of 40 male adult Sprague-Dawley rats were divided into four groups: sham-operated group (Sham), the two-vessel occlusion group (2VO), the 2VO treated with 4.5 g/kg/d TSD group (2VO + TSD-L), the 2VO treated with 13.5 g/kg/d TSD group (2VO + TSD-H). The rats underwent either 2VO surgery or sham surgery. Postoperative TSD treatment was given for 4 consecutive weeks. Behavioral tests were initiated at the end of gastrulation. Open-field test (OFT) was used to detect the activity level. The New Object Recognition test (NOR) was used to test long-term memory. The Morris water maze (MWM) test was used to examine the foundation of spatial learning and memory. As a final step, the hippocampus was taken for molecular testing. The protein levels of GRP78 (Bip), p-PERK, PERK, IRE1α, p-IRE1α, ATF6, eIF2α, p-eIF2α, ATF4, XBP1, Bcl-2 and Bax were determined by Western blot. Immunofluorescence visualizes molecular expression. RESULTS: In the OFT, residence time in the central area was significantly longer in both TSD treatment groups compared to the 2VO group. In the NOR, the recognition index was obviously elevated in both TSD treatment groups. The 2VO group had a significantly longer escape latency and fewer times in crossing the location of the platform compared with the Sham group in MWM. TSD treatment reversed this notion. Pathologically, staining observations confirmed that TSD inhibited hippocampal neuronal loss and alleviated the abnormal reduction of the Nissl body. In parallel, TUNEL staining illustrated that TSD decelerated neuronal apoptosis. Western Blot demonstrated that TSD reduces the expression of ERs and apoptotic proteins. CONCLUSION: In this study, the significant ameliorative effect on cognitive impairment of TSD has been determined by comparing the behavioral data of the 4 groups of rats. Furthermore, it was confirmed that this effect of TSD was achieved by suppressing the ERs-mediated apoptosis signaling pathway.

2.
Heliyon ; 10(9): e30505, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726194

RESUMO

FERMT2 has been identified as a participant in integrin-linked kinase signaling pathways, influencing epithelial-mesenchymal transition and thereby affecting tumor initiation, progression, and invasion. While the character of FERMT2 in the tumor microenvironment (TME) as well as its implications for immunotherapy remain unclear. Thus, we conducted a comprehensive analysis to assess the prognostic significance of FERMT2 using Kaplan-Meier analysis. In addition, we employed enrichment analysis to uncover potential underlying molecular mechanisms. Using "Immunedeconv" package, we evaluated the immune characteristics of FERMT2 within TME. Furthermore, we determined the expression levels of FERMT2 in various cell types within TME, based on single-cell sequencing data. To confirm the co-expression of FERMT2 and markers of cancer-associated fibroblasts (CAFs), we performed multiplex immunofluorescence staining on tissue paraffin sections across various cancer types. Our analysis disclosed a significant correlation between elevated FERMT2 expression and unfavorable prognosis in specific cancer types. Furthermore, we identified a strong correlation between FERMT2 expression and diverse immune-related factors, including immune checkpoint molecules, immune cell infiltration, microsatellite instability (MSI), and tumor mutational burden (TMB). Additionally, there was a significant correlation between FERMT2 expression and immune-related pathways, particularly those associated with activating, migrating, and promoting the growth of fibroblasts in diverse cancer types. Interestingly, we observed consistent co-expression of FERMT2 in both malignant tumor cells and stromal cells, particularly within CAFs. Notably, our findings also indicated that FERMT2, in particular, exhibited elevated expression levels within tumor tissues and co-expressed with α-SMA in CAFs based on the multiplex immunofluorescence staining results.

3.
Plant Methods ; 20(1): 65, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725004

RESUMO

BACKGROUND: Citrus canker is a significant bacterial disease caused by Xanthomonas citri subsp. citri (Xcc) that severely impedes the healthy development of the citrus industry. Especially when citrus fruit is infected by Xcc, it will reduce or even lost its commercial value. However, due to the prolonged fruiting cycle and intricate structure, much less research progress had been made in canker disease on fruit than on leaf. In fact, limited understanding has been achieved on canker development and the response to Xcc infection in fruit. RESULTS: Herein, the progression of canker disease on sweet orange fruit was tracked in the field. Results indicated that typical lesions initially appear on the sepal, style residue, nectary disk, epicarp, and peduncle of young fruits after petal fall. The susceptibility of fruits to Xcc infection diminished as the fruit developed, with no new lesions forming at the ripening stage. The establishment of an efficient method for inoculating Xcc on fruit as well as the artificial inoculation throughout the fruit's developmental cycle clarified this infection pattern. Additionally, microscopic observations during the infection process revealed that Xcc invasion caused structural changes on the surface and cross-section of the fruit. CONCLUSIONS: An efficient system for inoculation on citrus fruit with Xcc was established, by which it can serve for the evaluation of citrus germplasm for canker disease resistance and systematic research on the interactions between Xcc and citrus fruits.

4.
Angew Chem Int Ed Engl ; : e202401850, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38706222

RESUMO

Seeking high-performance photoresist is an important item for semiconductor industry due to the continuous miniaturization and intelligentization of integrated circuits. Polymer resin containing carbonate group has many desirable properties, such as high transmittance, acid sensitivity and chemical formulation, thus serving as potential photoresist material. In this work, a series of aqueous developable CO2-sourced polycarbonate (CO2-PC) were produced via alternating copolymerization of CO2 and epoxides bearing acid-cleavable cyclic acetal groups in the presence of tetranuclear organoborane catalyst. The produced CO2-PCs were investigated as chemical amplification resists in deep ultraviolet (DUV) lithography. Under the catalysis of photoacid, the acetal (ketal) groups in CO2-PC were hydrolysed into two equivalents of hydroxyl groups, which changes the exposed areas from hydrophobicity to hydrophilicity, thus enabling the exposed regions to be developed in water. Through normalized remaining thickness analysis, the optimal CO2-derived resist achieved a remarkable sensitivity of 1.9 mJ/cm2, a contrast of 7.9, a favorable resolution (750 nm, half pitch), and etching resistance (38% higher than poly(tert-butyl acrylate)). Such performances outperforming commercial KrF and ArF chemical amplification resists (i.e., polyhydroxystyrene-derived and polymethacrylate-based resists), which endows broad application prospects in the field of DUV (248 nm and 193 nm) and extreme ultraviolet (EUV) lithography and nanomanufacturing.

5.
Plant Cell Physiol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757845

RESUMO

Whole genome duplication (WGD) events are widespread in plants and animals, thus their long-term evolutionary contribution has long been speculated, yet a specific contribution is difficult to verify. Here, we show that ɛ-WGD and ζ-WGD contribute to the origin and evolution of bona fide brassinosteroid (BR) signaling through the innovation of active BR biosynthetic enzymes and active BR receptors from their respective ancestors. We found that BR receptors BRI1 (BR Insensitive 1) and BRL1/3 (BRI1-likes 1/3) derived by ɛ-WGD and ζ-WGD, which occurred in the common ancestor of angiosperms and seed plants, respectively, while orphan BR receptor BRL2 first appeared in stomatophytes. Additionally, CYP85A enzymes synthesizing the bioactive BRs derived from a common ancestor of seed plants while its sister enzymes CYP90 synthesizing BR precursors presented in all land plants, implying possible ligand-receptor coevolution. Consistently, the island domains (IDs) responsible for BR perception in BR receptors were most divergent among different receptor branches, supporting ligand-driven evolution. As a result, BRI1 was the most diversified BR receptor in angiosperms. Importantly, relative to the BR biosynthetic DET2 gene presented in all land plants, BRL2, BRL1/3 and BRI1 had high expression in vascular plants ferns, gymnosperms and angiosperms, respectively. Notably, BRI1 is the most diversified BR receptor with the most abundant expression in angiosperms, suggesting potential positive selection. Therefore, WGDs initiate a neofunctionalization process diverged by ligand-perception and transcriptional expression, which might optimize both BR biosynthetic enzymes and BR receptors, likely contributing to the evolution of land plants, especially seed plants and angiosperms.

6.
Medicine (Baltimore) ; 103(21): e37883, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38788020

RESUMO

BACKGROUND: Hyperlipidemia is a common feature of chronic diseases. The aim of this work was designed to assess the role of probiotics (Lactobacillus casei Zhang, Bifidobactetium animalis subsp. lactis V9, and Lactobacillus plantarum P-8) in the treatment of hyperlipidemia. METHODS: Thirty three patients with hyperlipidemia were randomly divided into a probiotic group (n = 18) and a control group (n = 15). The probiotic group was administered probiotics (2 g once daily) and atorvastatin 20 mg (once daily), and the control group was administered a placebo (2 g once daily) and atorvastatin 20 mg (once daily). Serum and fecal samples were gathered for subsequent analyses. RESULTS: Time had a significant effect on the total cholesterol (TC), triglycerides (TG), and low-density lipoprotein-cholesterol (LDL-C) levels in the probiotic and control groups (P < .05). The gut microbial abundance in the probiotic group was markedly higher than that in the control group following 3-month probiotic treatment (P < .05). At the phylum level, probiotics exerted no notable effects on the relative abundance of Firmicutes, Bacteroidetes, and Actinobacteria but elevated that of Tenericutes and reduced Proteobacteria. At the genus level, probiotics increased the relative abundance of Bifidobacterium, Lactobacillus, and Akkermansia, and decreased that of Escherichia, Eggerthella, and Sutterella relative to the control group in months 1, 2, and 3 (P < .05). CONCLUSIONS: Probiotics optimize the gut microbiota structure and decrease the amount of harmful bacteria in patients with hyperlipidemia. Probiotics can influence the composition of gut microorganisms and increase their diversity and abundance in vivo. It is recommended to use probiotics combined with atorvastatin to treat patients with hyperlipidemia.


Assuntos
Atorvastatina , Microbioma Gastrointestinal , Hiperlipidemias , Probióticos , Humanos , Atorvastatina/administração & dosagem , Atorvastatina/uso terapêutico , Probióticos/administração & dosagem , Probióticos/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Método Duplo-Cego , Masculino , Feminino , Pessoa de Meia-Idade , Microbioma Gastrointestinal/efeitos dos fármacos , Adulto , Resultado do Tratamento , Triglicerídeos/sangue , LDL-Colesterol/sangue , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/uso terapêutico , Lactobacillus plantarum , Fezes/microbiologia , Idoso , Terapia Combinada
7.
Behav Brain Res ; 468: 114999, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38615978

RESUMO

Itch is one of the most common clinical symptoms in patients with diseases of the skin, liver, or kidney, and it strongly triggers aversive emotion and scratching behavior. Previous studies have confirmed the role of the prelimbic cortex (Prl) and the nucleus accumbens core (NAcC), which are reward and motivation regulatory centers, in the regulation of itch. However, it is currently unclear whether the Prl-NAcC projection, an important pathway connecting these two brain regions, is involved in the regulation of itch and its associated negative emotions. In this study, rat models of acute neck and cheek itch were established by subcutaneous injection of 5-HT, compound 48/80, or chloroquine. Immunofluorescence experiments determined that the number of c-Fos-immunopositive neurons in the Prl increased during acute itch. Chemogenetic inhibition of Prl glutamatergic neurons or Prl-NAcC glutamatergic projections can inhibit both histaminergic and nonhistaminergic itch-scratching behaviors and rectify the itch-related conditioned place aversion (CPA) behavior associated with nonhistaminergic itch. The Prl-NAcC projection may play an important role in the positive regulation of itch-scratching behavior by mediating the negative emotions related to itch.


Assuntos
Vias Neurais , Núcleo Accumbens , Prurido , Ratos Sprague-Dawley , Animais , Prurido/fisiopatologia , Núcleo Accumbens/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Masculino , Ratos , Vias Neurais/fisiologia , Vias Neurais/fisiopatologia , Modelos Animais de Doenças , Neurônios/fisiologia , Aprendizagem da Esquiva/fisiologia , Comportamento Animal/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo
8.
Angew Chem Int Ed Engl ; : e202404207, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647637

RESUMO

Alkyl borane compounds-mediated polymerizations have expanded to Lewis pair polymerization, free radical polymerization, ionic ring-opening polymerization, and polyhomologation. The bifunctional organoborane catalysts that contain the Lewis acid and ammonium or phosphonium salt in one molecule have demonstrated superior catalytic performance for ring-opening polymerization of epoxides and ring-opening copolymerization of epoxides and CO2 than their two-component analogues, i.e., the blend of organoborane and ammonium or phosphonium salt. To explore the origin of the differences of the one-component and two-component organoborane catalysts, here we conducted a systematic investigation on the catalytic performances of these two kinds of organoborane catalysts via terpolymerization of epoxide, carbon dioxide and anhydride. The resultant terpolymers produced independently by bifunctional and binary organoborane catalyst exhibited distinct microstructures, where a series of gradient polyester-polycarbonate terpolymers with varying polyester content were afforded using the bifunctional catalyst, while tapering diblock terpolymers were obtained using the binary system. The bifunctional catalyst enhances the competitiveness of CO2 insertion than anhydride, which leads to the premature incorporation of CO2 into the polymer chains and ultimately results in the formation of gradient terpolymers. DFT calculations revealed the role of electrostatic interaction and charge distribution caused by intramolecular synergistic effect for bifunctional organoborane catalyst.

9.
Ecotoxicol Environ Saf ; 274: 116124, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503108

RESUMO

OBJECTIVE: The primary objective of this study was to investigate the toxicological impact of Dibutyl phthalate (DBP) on the process of liver fibrosis transitioning into cirrhosis and the subsequent development of portal hypertension (PHT) through the mechanism of epithelial-mesenchymal transition (EMT) mediated by the ROS/TGF-ß/Snail-1 signaling pathway. METHOD: Carbon tetrachloride (CCl4) (1 mg/kg) was introduced in adult rats by oral feeding in CCl4 and CCl4+DBP groups twice a week for 8 weeks, and twice for another 8 week in CCl4 group. DBP was introduced by oral feeding in the CCl4+DBP group twice over the following 8 weeks. We subsequently analyzed hemodynamics measurements and liver cirrhosis degree, hepatic inflammation and liver function in the different groups. EMT related genes expression in rats in the groups of Control, DBP, CCl4 and CCl4+DBP were measured by immunohistochemistry (IHC). Enzyme-linked immunosorbent Assay (ELISA), qRT-PCR, western blot were used to detect the EMT related proteins and mRNA gene expression levels in rats and primary hepatocytes (PHCs). Reactive oxygen species (ROS) were examined with a ROS detection kit. RESULTS: The results showed that the CCl4+DBP group had higher portal pressure (PP) and lower mean arterial pressure (MAP) than the other groups. Elevated collagen deposition, profibrotic factor, inflammation, EMT levels were detected in DBP and CCl4+DBP groups. ROS, TGF-ß1 and Snail-1 were highly expressed after DBP exposure in vitro. TGF-ß1 had the potential to regulate Snail-1, and both of them were subject to regulation by ROS. CONCLUSION: DBP could influence the progression of EMT through its toxicological effect by ROS/TGF-ß1/Snail-1 signalling pathway, causing cirrhosis and PHT in final. The findings of this research might contribute to a novel comprehension of the underlying toxicological mechanisms and animal model involved in the progression of cirrhosis and PHT, and potentially offered a promising therapeutic target for the treatment of the disease.


Assuntos
Dibutilftalato , Transição Epitelial-Mesenquimal , Hipertensão Portal , Fator de Crescimento Transformador beta1 , Animais , Ratos , Dibutilftalato/toxicidade , Fibrose , Hipertensão Portal/induzido quimicamente , Inflamação , Cirrose Hepática/induzido quimicamente , Espécies Reativas de Oxigênio , Transdução de Sinais , Fatores de Transcrição da Família Snail/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
10.
IET Syst Biol ; 18(2): 55-75, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458989

RESUMO

The main objective was to establish a prognostic model utilising long non-coding RNAs associated with disulfidptosis and cuproptosis. The data for RNA-Sequence and clinicopathological information of Colon adenocarcinoma (COAD) were acquired from The Cancer Genome Atlas. A prognostic model was constructed using Cox regression and the Least Absolute Shrinkage and Selection Operator method. The model's predictive ability was assessed through principal component analysis, Kaplan-Meier analysis, nomogram etc. The ability of identifying the rates of overall survival, infiltration of immune cells, and chemosensitivity was also explored. In vitro experiments were conducted for the validation of differential expression and function of lncRNAs. A disulfidptosis and cuproptosis-related lncRNA prognostic model was constructed. The prognostic model exhibits excellent independent predictive capability for patient outcomes. Based on the authors' model, the high-risk group exhibited higher tumour mutation burdened worse survival. Besides, differences in immune cell infiltration and responsiveness to chemotherapeutic medications exist among patients with different risk scores. Furthermore, aberrant expressions in certain lncRNAs have been validated in HCT116 cells. In particular, FENDRR and SNHG7 could affect the proliferation and migration of colorectal cancer cells. Our study developed a novel prognostic signature, providing valuable insights into prognosis, immune infiltration, and chemosensitivity in COAD patients.


Assuntos
Adenocarcinoma , Neoplasias do Colo , RNA Longo não Codificante , Humanos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , RNA Longo não Codificante/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Estimativa de Kaplan-Meier , Mutação , Microambiente Tumoral
11.
Phytomedicine ; 128: 155500, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38484627

RESUMO

Ginger, a well-known spice plant, has been used widely in medicinal preparations for pain relief. However, little is known about its analgesic components and the underlying mechanism. Here, we ascertained, the efficacy of ginger ingredient 8-Shogaol (8S), on inflammatory pain and tolerance induced by morphine, and probed the role of TRPV1 in its analgesic action using genetic and electrophysiology approaches. Results showed that 8S effectively reduced nociceptive behaviors of mice elicited by chemical stimuli, noxious heat as well as inflammation, and antagonized morphine analgesic tolerance independent on opioid receptor function. Genetic deletion of TRPV1 significantly abolished 8S' analgesia action. Further calcium imaging and patch-clamp recording showed that 8S could specifically activate TRPV1 in TRPV1-expressing HEK293T cells and dorsal root ganglion (DRG) neurons. The increase of [Ca2+]i in DRG was primarily mediated through TRPV1. Mutational and computation studies revealed the key binding sites for the interactions between 8S and TRPV1 included Leu515, Leu670, Ile573, Phe587, Tyr511, and Phe591. Further studies showed that TRPV1 activation evoked by 8S resulted in channel desensitization both in vitro and in vivo, as may be attributed to TRPV1 degradation or TRPV1 withdrawal from the cell surface. Collectively, this work provides the first evidence for the attractive analgesia of 8S in inflammatory pain and morphine analgesic tolerance mediated by targeting pain-sensing TRPV1 channel. 8S from dietary ginger has potential as a candidate drug for the treatment of inflammatory pain.


Assuntos
Catecóis , Gânglios Espinais , Canais de Cátion TRPV , Zingiber officinale , Canais de Cátion TRPV/metabolismo , Zingiber officinale/química , Animais , Humanos , Células HEK293 , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Catecóis/farmacologia , Camundongos , Masculino , Camundongos Endogâmicos C57BL , Inflamação/tratamento farmacológico , Analgésicos/farmacologia , Morfina/farmacologia , Cálcio/metabolismo
12.
Biol Chem ; 405(5): 341-349, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38424700

RESUMO

Therapy-related leukemia carries a poor prognosis, and leukemia after chemotherapy is a growing risk in clinic, whose mechanism is still not well understood. Ikaros transcription factor is an important regulator in hematopoietic cells development and differentiation. In the absence of Ikaros, lymphoid cell differentiation is blocked at an extremely early stage, and myeloid cell differentiation is also significantly affected. In this work, we showed that chemotherapeutic drug etoposide reduced the protein levels of several isoforms of Ikaros including IK1, IK2 and IK4, but not IK6 or IK7, by accelerating protein degradation, in leukemic cells. To investigate the molecular mechanism of Ikaros degradation induced by etoposide, immunoprecipitation coupled with LC-MS/MS analysis was conducted to identify changes in protein interaction with Ikaros before and after etoposide treatment, which uncovered KCTD5 protein. Our further study demonstrates that KCTD5 is the key stabilizing factor of Ikaros and chemotherapeutic drug etoposide induces Ikaros protein degradation through decreasing the interaction of Ikaros with KCTD5. These results suggest that etoposide may induce leukemic transformation by downregulating Ikaros via KCTD5, and our work may provide insights to attenuate the negative impact of chemotherapy on hematopoiesis.


Assuntos
Etoposídeo , Fator de Transcrição Ikaros , Fator de Transcrição Ikaros/metabolismo , Etoposídeo/farmacologia , Humanos , Proteólise/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia
13.
Huan Jing Ke Xue ; 45(2): 1173-1184, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471954

RESUMO

The effect of microplastics on the ecological environment and human health has become a topical issue, and research on the risks and harmful effects of MPs on human health in particular has attracted widespread attention. Due to the characteristics of small size, low degradability, and easy migration, MPs continuously migrate from the environment to the human body, and their main exposure pathways are oral ingestion, inhalation, and dermal contact, with the main exposure media being food, drinking water, dust, personal care products, etc. MPs have been detected in organs, fluids, and excreta of digestive, respiratory, cardiovascular, reproductive systems, etc. The abundance range of MPs in the human body is 0-1 206.94 particles per gram. After entering the human body, MPs can cause cytotoxicity, mitochondrial toxicity, DNA damage, cell membrane damage, and other effects on human cells and organs, leading to serious consequences such as local inflammation, ecological imbalance, metabolic disorders, etc., in various systems. Owing to their small specific surface area, they can also adsorb pollutants such as heavy metals, organic pollutants, antibiotics, pathogens, and harmful microorganisms, causing combined toxicity and immunotoxicity. In the end, we highlighted general deficiencies in existing studies and provided directions for future research on the influence of MPs on human health.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
14.
Chem Soc Rev ; 53(7): 3384-3456, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38411207

RESUMO

The scientific community has witnessed extensive developments and applications of organoboron compounds as synthetic elements and metal-free catalysts for the construction of small molecules, macromolecules, and functional materials over the last two decades. This review highlights the achievements of organoboron-mediated polymerizations in the past several decades alongside the mechanisms underlying these transformations from the standpoint of the polymerization mode. Emphasis is placed on free radical polymerization, Lewis pair polymerization, ionic (cationic and anionic) polymerization, and polyhomologation. Herein, alkylborane/O2 initiating systems mediate the radical polymerization under ambient conditions in a controlled/living manner by careful optimization of the alkylborane structure or additives; when combined with Lewis bases, the selected organoboron compounds can mediate the Lewis pair polymerization of polar monomers; the bicomponent organoboron-based Lewis pairs and bifunctional organoboron-onium catalysts catalyze ring opening (co)polymerization of cyclic monomers (with heteroallenes, such as epoxides, CO2, CO, COS, CS2, episulfides, anhydrides, and isocyanates) with well-defined structures and high reactivities; and organoboranes initiate the polyhomologation of sulfur ylides and arsonium ylides providing functional polyethylene with different topologies. The topological structures of the produced polymers via these organoboron-mediated polymerizations are also presented in this review mainly including linear polymers, block copolymers, cyclic polymers, and graft polymers. We hope the summary and understanding of how organoboron compounds mediate polymerizations can inspire chemists to apply these principles in the design of more advanced organoboron compounds, which may be beneficial for the polymer chemistry community and organometallics/organocatalysis community.

15.
Chemistry ; 30(25): e202400390, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38381600

RESUMO

Reaction of [CuH(PPh3)]6 with 1 equiv. of Tl(OTf) results in formation of [Cu6TlH6(PPh3)6][OTf] ([1]OTf]), which can be isolated in good yields. Variable-temperature 1H NMR spectroscopy, in combination with density functional theory (DFT) calculations, confirms the presence of a rare Tl-H orbital interaction. According to DFT, the 1H chemical shift of the Tl-adjacent hydride ligands of [1]+ includes 7.7 ppm of deshielding due to spin-orbit effects from the heavy Tl atom. This study provides valuable new insights into a rare class of metal hydrides, given that [1][OTf] is only the third isolable species reported to contain a Tl-H interaction.

16.
Front Plant Sci ; 15: 1305599, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38362444

RESUMO

All living organisms must develop mechanisms to cope with and adapt to new environments. The transition of plants from aquatic to terrestrial environment provided new opportunities for them to exploit additional resources but made them vulnerable to harsh and ever-changing conditions. As such, the transmembrane receptor-like kinases (RLKs) have been extensively duplicated and expanded in land plants, increasing the number of RLKs in the advanced angiosperms, thus becoming one of the largest protein families in eukaryotes. The basic structure of the RLKs consists of a variable extracellular domain (ECD), a transmembrane domain (TM), and a conserved kinase domain (KD). Their variable ECDs can perceive various kinds of ligands that activate the conserved KD through a series of auto- and trans-phosphorylation events, allowing the KDs to keep the conserved kinase activities as a molecular switch that stabilizes their intracellular signaling cascades, possibly maintaining cellular homeostasis as their advantages in different environmental conditions. The RLK signaling mechanisms may require a coreceptor and other interactors, which ultimately leads to the control of various functions of growth and development, fertilization, and immunity. Therefore, the identification of new signaling mechanisms might offer a unique insight into the regulatory mechanism of RLKs in plant development and adaptations. Here, we give an overview update of recent advances in RLKs and their signaling mechanisms.

17.
Eur J Med Chem ; 267: 116170, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38308950

RESUMO

As an important characteristic of tumor, acidic tumor microenvironment (TME) is closely related to immune escape, invasion, migration and drug resistance of tumor. The acidity of the TME mainly comes from the acidic products produced by the high level of tumor metabolism, such as lactic acid and carbon dioxide. pH regulators such as monocarboxylate transporters (MCTs), carbonic anhydrase IX (CA IX), and Na+/H+ exchange 1 (NHE1) expel protons directly or indirectly from the tumor to maintain the pH balance of tumor cells and create an acidic TME. We review the functions of several pH regulators involved in the construction of acidic TME, the structure and structure-activity relationship of pH regulator inhibitors, and provide strategies for the development of small-molecule antitumor inhibitors based on these targets.


Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Anidrases Carbônicas/metabolismo , Microambiente Tumoral , Anidrase Carbônica IX/metabolismo , Neoplasias/metabolismo , Antígenos de Neoplasias/metabolismo , Prótons , Concentração de Íons de Hidrogênio , Inibidores da Anidrase Carbônica/farmacologia
18.
Anal Methods ; 16(3): 427-433, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38165671

RESUMO

The detection of human serum albumin (HSA) in bodily fluids is of great significance in the biomedical area because HSA in bodily fluids is commonly used as a biomarker for the early diagnosis of diseases. To detect HSA, we employed HDBB, 4,4'-(hydrazine-1,2-diylidene bis(methanylylidene)) bis(3-hydroxybenzoic acid), as a fluorescent probe with a large Stokes shift. HDBB had obvious excited state intramolecular proton transfer (ESIPT) and aggregation-induced emission (AIE) features. We elucidated the ESIPT characteristics of HDBB through the DFT approach. We also performed a molecular docking simulation between HDBB and HSA, showing that HDBB primarily bonded to HSA via hydrophobic force and hydrogen bonds. The FL intensities of HDBB with HSA concentrations had a linear range of 0.01-0.2 mg mL-1 (R2 = 0.9995), and the LOD was 1.104 µg mL-1. We also used the probe to detect HSA in urine, with spiked recoveries of 98.10-105.33%. Given its high selectivity and feasible synthesis, HDBB has potential applications in detecting HSA in real biological systems.


Assuntos
Corantes Fluorescentes , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Simulação de Acoplamento Molecular , Prótons
19.
Food Chem ; 443: 138509, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277940

RESUMO

Biogenic amines (BAs) produced by microbial decarboxylation of amino acids are crucial toxic nitrogenous compounds in fish. An optimized ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method with simple pretreatment was established to detect 14 BAs in both raw (control check, CK) and deep-fried (DF) hairtails. This method exhibited a good linear relationship with average recoveries of 73.3-120.0 % and relative standard deviations of 2.5-10.0 %, respectively. The total BAs in CK and DF hairtails decreased sharply to 338.2 and 25.3 mg/kg on the 9th day, respectively. Four BAs, including cadaverine (CAD), histamine (HIS), tyramine (TYR), and putrescine (PUT) accounted for 92.5-99.9 % of total BAs were selected as the dominant BAs. Bacterial analysis showed that the abundance of DF was relatively low. Further correlation analysis proved that Vibrio had a significant (p < 0.05) positive correlation with total BAs and could be the main BA-producing bacterium in DF hairtail. This work provides new evidence of the accumulation of BAs in refrigerated hairtail.


Assuntos
Perciformes , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Aminas Biogênicas/análise , Histamina/análise , Cromatografia Líquida de Alta Pressão/métodos
20.
Aging (Albany NY) ; 16(3): 2385-2397, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38284892

RESUMO

Evodia lepta Merr. (Evodia lepta) is a well-known traditional Chinese medicine, which has been widely used in herbal tea. We previously reported that the coumarin compounds from the root of Evodia lepta exhibited neuroprotective effects. However, whether Evodia lepta could inhibit NLRP3 inflammasome in dementia was still unknown. In this study, the components of the Evodia lepta extract were identified by HPLC-Q-TOF HRMS. We employed a scopolamine-treated mouse model. Evodia lepta extract (10 or 20 mg/kg) and donepezil were treated by gavage once a day for 14 consecutive days. Following the behavioral tests, oxidative stress levels were measured. Then, Western blot and immunofluorescence analysis were used to evaluate the expressions of NLRP3 inflammasome. 14 major components of the Evodia lepta extract were identified by HPLC-Q-TOF HRMS. The results of Morris water maze, object recognition task and open field test indicated that Evodia lepta extract could ameliorate cognitive impairment in scopolamine-treated mice. Evodia lepta extract improved cholinergic system. Moreover, Evodia lepta extract improved the expressions of PSD95 and BDNF. Evodia lepta extract suppressed neuronal oxidative stress and apoptosis. In addition, Evodia lepta extract inhibited NLRP3 inflammasome in the hippocampus of scopolamine-treated mice. Evodia lepta extract could protect against cognitive impairment by inhibiting NLRP3 inflammasome in scopolamine-treated mice.


Assuntos
Disfunção Cognitiva , Evodia , Camundongos , Animais , Inflamassomos , Evodia/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Escopolamina/toxicidade , Etanol/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo
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