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Formal total syntheses of stemonamine and cephalotaxine bearing the core cyclopenta[1,2-b]pyrrolo[1,2-a]azepine ring skeleton were achieved. The general synthetic strategy in the synthesis features the reductive oxy-Nazarov cyclization as key step, leading to the versatile construction of N-substituted spiro quaternary stereogenic centers from readily available starting materials.
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A reinvestigation of "Phosphine-Mediated Reductive Condensation of γ-Acyloxy Butynoates: A Diversity Oriented Strategy for the Construction of Substituted Furans" (J. Am. Chem. Soc. 2004, 126, 4118-4119) revealed different chemoselectivity of triphenylphosphine in the reactions with the γ-acyloxy butynoate substrates of varying substitution patterns/electronics. Furthermore, the electronics of the triaryl phosphine reagent could be tuned to trap a putative intermediate such as A, leading to the semihydrogenation of propiolamide substrates.
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The sluggish kinetics of oxygen reduction reactions (ORRs) require considerable Pd in the cathode, hindering the widespread of alkaline fuel cells (AFCs). By alloying Pd with transition metals, the oxygen reduction reaction's catalytic properties can be substantially enhanced. Nevertheless, the utilization of Pd-transition metal alloys in fuel cells is significantly constrained by their inadequate long-term durability due to the propensity of transition metals to leach. In this study, a nonmetallic doping strategy was devised and implemented to produce a Pd catalyst doped with P that exhibited exceptional durability towards ORRs. Pd3P0.95 with an average size of 6.41 nm was synthesized by the heat-treatment phosphorization of Pd nanoparticles followed by acid etching. After P-doping, the size of the Pd nanoparticles increased from 5.37 nm to 6.41 nm, and the initial mass activity (MA) of Pd3P0.95/NC reached 0.175 A mgPd-1 at 0.9 V, slightly lower than that of Pd/C. However, after 40,000 cycles of accelerated durability testing, instead of decreasing, the MA of Pd3P0.95/NC increased by 6.3% while the MA loss of Pd/C was 38.3%. The durability was primarily ascribed to the electronic structure effect and the aggregation resistance of the Pd nanoparticles. This research also establishes a foundation for the development of Pd-based ORR catalysts and offers a direction for the future advancement of catalysts designed for practical applications in AFCs.
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Previous research has indicated that higher red blood cell distribution width (RDW) increases the risk of coronary heart disease. However, no studies have established a link between RDW and coronary heart disease in the rheumatoid arthritis population. This research aims to explore the association between RDW and coronary heart disease among individuals with rheumatoid arthritis. We selected demographic data, laboratory data, lifestyle, and medical history from the National Health and Nutrition Examination Survey (NHANES), specifically including age, gender, poverty, RDW, race, BMI, diabetes, education, coronary heart disease, hypertension, cholesterol, smoking, and drinking. RDW and coronary heart disease were found to have a positive association in the rheumatoid arthritis population (ORâ =â 1.145, 95%CI: 1.036-1.266, Pâ =â .0098), even after adjusting for factors such as age, gender, race, education level, smoking, and drinking. Subgroup analysis showed a stronger positive association, particularly in individuals aged 55-66 years, males, and the Hispanic White population with diabetes or hypercholesterolemia. There is a significant correlation between RDW and coronary heart disease among individuals with rheumatoid arthritis.
Assuntos
Artrite Reumatoide , Doença das Coronárias , Diabetes Mellitus , Masculino , Humanos , Inquéritos Nutricionais , Estudos Transversais , Artrite Reumatoide/complicações , Artrite Reumatoide/epidemiologia , Doença das Coronárias/epidemiologia , Índices de EritrócitosRESUMO
BACKGROUND: Herba Patriniae and Coix seed (HC) constitute a widely utilized drug combination in the clinical management of colorectal cancer (CRC) that is known for its diuretic, anti-inflammatory, and swelling-reducing properties. Although its efficacy has been demonstrated in a clinical setting, the active compounds and their mechanisms of action in CRC treatment remain to be fully elucidated. AIM: To identify the active, CRC-targeting components of HC and to elucidate the mechanisms of action involved. METHODS: Active HC components were identified and screened using databases. Targets for each component were predicted. CRC-related targets were obtained from human gene databases. Interaction targets between HC and CRC were identified. A "drug-ingredient-target" network was created to identify the core components and targets involved. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to elucidate the key pathways involved. Molecular docking between core targets and key components was executed. In vitro experiments validated core monomers. RESULTS: Nineteen active components of HC were identified, with acacetin as the primary active compound. The predictive analysis identified 454 targets of the active compounds in HC. Intersection mapping with 2685 CRC-related targets yielded 171 intervention targets, including 30 core targets. GO and KEGG analyses indicated that HC may influence the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Molecular docking showed that acacetin exhibited an optimal interaction with AKT1, identifying PI3K, AKT, and P53 as key genes likely targeted by HC during CRC treatment. Acacetin inhibited HT-29 cell proliferation and migration, as well as promoted apoptosis, in vitro. Western blotting analysis revealed increased p53 and cleaved caspase-3 expression and decreased levels of p-PI3K, p-Akt, and survivin, which likely contributed to CRC apoptosis. CONCLUSION: Acacetin, the principal active compound in the HC pair, inhibited the proliferation and migration of HT-29 cells and promoted apoptosis through the PI3K/Akt/p53 signaling pathway.
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Migratory birds play an important role in the cross-regional transmission of zoonotic pathogens. Assessing the presence of zoonotic pathogens carried by migratory birds is critical for disease control. However, information about Blastocystis infection in the migratory birds is very limited. Thus, we conducted this study with the aim to explore the occurrence, prevalence and subtyping of Blastocystis in four breeds of migratory birds in northeastern China. From October 2022 to April 2023, a total of 427 fresh fecal samples were obtained from four breeds of migratory birds in five nature reserves in northeastern China, and screened for Blastocystis by PCR amplification. Twenty-one (4.92 %) of the studied samples were confirmed Blastocystis-positive, and two known zoonotic subtypes ST6 and ST7 were founded, with ST7 being the major subtype. Until now, we firstly reported the infection status and subtyping of Blastocystis in the migratory Greater White-Fronted Goose, White Stork, Oriental White Stork and Bean Goose in China. More importantly, these findings present further data on the genetic diversity and transmission routes of Blastocystis and further arouse public health concerns about this organism.
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BACKGROUND: Administration of olanzapine (OLA) is closely associated with obesity and glycolipid abnormalities in patients with schizophrenia (SCZ), although the exact molecular mecha- nisms remain elusive. OBJECTIVE: We conducted comprehensive animal and molecular experiments to elucidate the mecha- nisms underlying OLA-induced weight gain. METHODS: We investigated the mechanisms of OLA-induced adipogenesis and lipid storage by em- ploying a real-time ATP production rate assay, glucose uptake test, and reactive oxygen species (ROS) detection in 3T3-L1 cells and AMSCs. Rodent models were treated with OLA using various interven- tion durations, dietary patterns (normal diets/western diets), and drug doses. We assessed body weight, epididymal and liver fat levels, and metabolic markers in both male and female mice. RESULTS: OLA accelerates adipogenesis by directly activating glycolysis and its downstream PI3K sig- naling pathway in differentiated adipocytes. OLA promotes glucose uptake in differentiated 3T3-L1 preadipocytes. In mouse models with normal glycolipid metabolism, OLA administration failed to in- crease food intake and weight gain despite elevated GAPDH expression, a marker related to glycolysis and PI3K-AKT. This supports the notion that glycolysis plays a significant role in OLA-induced met- abolic dysfunction. CONCLUSION: OLA induces glycolysis and activates the downstream PI3K-AKT signaling pathway, thereby promoting adipogenesis.
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BACKGROUND: Alzheimer's disease (AD) is a degenerative neurological disorder. Recent studies have indicated that histone deacetylases (HDACs) are among the most prominent epigenetic therapy targets and that HDAC inhibitors have therapeutic effects on AD. Here, we identified sodium valproate (VPA), a pan-HDAC inhibitor, and WT161, a novel HDAC6 selective inhibitor, as potential therapeutic agents for AD. Underlying molecular mechanisms were investigated. METHODS: A cellular model, N2a-APPswe, was established via lentiviral infection, and the APPswe/PSEN1dE9 transgenic mouse model was employed in the study. LC-MS/MS was applied to quantify the concentration of WT161 in the mouse brain. Western blotting, immunohistochemical staining, thioflavin-S staining and ELISA were applied to detect protein expression in cells, tissues, or serum. RNA interference was utilized to knockdown the expression of specific genes in cells. The cognitive function of mice was assessed via the nest-building test, novel object recognition test and Morris water maze test. RESULTS: Previous studies have focused mainly on the impact of HDAC inhibitors on histone deacetylase activity. Our study discovered that VPA and WT161 can downregulate the expression of multiple HDACs, such as HDAC1 and HDAC6, in both AD cell and mouse models. Moreover, they also affect the expression of APP and APP secretases (BACE1, PSEN1, ADAM10). RNA interference and subsequent vitamin C induction further confirmed that the expression of APP and APP secretases is indeed regulated by HDAC1 and HDAC6, with the JNK pathway being the intermediate link in this regulatory process. Through the above pathways, VPA and WT161 effectively reduced Aß deposition in both AD cell and mouse models and significantly improved cognitive function in AD mice. CONCLUSIONS: In general, we have discovered that the HDAC6-JNK-APP secretases cascade is an important pathway for VPA and WT161 to exert their therapeutic effects on AD. Investigations into the safety and efficacy of VPA and WT161 were also conducted, providing essential preclinical evidence for assessing these two epigenetic drugs for the treatment of AD.