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1.
N Engl J Med ; 388(21): 1966-1980, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37224198

RESUMEN

BACKGROUND: Upadacitinib, an oral selective Janus kinase (JAK) inhibitor, is under investigation for the treatment of Crohn's disease. METHODS: In two phase 3 induction trials (U-EXCEL and U-EXCEED), we randomly assigned patients with moderate-to-severe Crohn's disease to receive 45 mg of upadacitinib or placebo (2:1 ratio) once daily for 12 weeks. Patients who had a clinical response to upadacitinib induction therapy were randomly assigned in the U-ENDURE maintenance trial to receive 15 mg of upadacitinib, 30 mg of upadacitinib, or placebo (1:1:1 ratio) once daily for 52 weeks. The primary end points for induction (week 12) and maintenance (week 52) were clinical remission (defined as a Crohn's Disease Activity Index score of <150 [range, 0 to 600, with higher scores indicating more severe disease activity]) and endoscopic response (defined as a decrease in the Simple Endoscopic Score for Crohn's Disease [SES-CD; range, 0 to 56, with higher scores indicating more severe disease] of >50% from baseline of the induction trial [or for patients with an SES-CD of 4 at baseline, a decrease of ≥2 points from baseline]). RESULTS: A total of 526 patients underwent randomization in U-EXCEL, 495 in U-EXCEED, and 502 in U-ENDURE. A significantly higher percentage of patients who received 45-mg upadacitinib than those who received placebo had clinical remission (in U-EXCEL, 49.5% vs. 29.1%; in U-EXCEED, 38.9% vs. 21.1%) and an endoscopic response (in U-EXCEL, 45.5% vs. 13.1%; in U-EXCEED, 34.6% vs. 3.5%) (P<0.001 for all comparisons). At week 52 in U-ENDURE, a higher percentage of patients had clinical remission with 15-mg upadacitinib (37.3%) or 30-mg upadacitinib (47.6%) than with placebo (15.1%), and a higher percentage had an endoscopic response with 15-mg upadacitinib (27.6%) or 30-mg upadacitinib (40.1%) than with placebo (7.3%) (P<0.001 for all comparisons). Herpes zoster infections occurred more frequently in the 45-mg and 30-mg upadacitinib groups than in the respective placebo groups, and hepatic disorders and neutropenia were more frequent in the 30-mg upadacitinib group than in the other maintenance groups. Gastrointestinal perforations developed in 4 patients who received 45-mg upadacitinib and in 1 patient each who received 30-mg or 15-mg upadacitinib. CONCLUSIONS: Upadacitinib induction and maintenance treatment was superior to placebo in patients with moderate-to-severe Crohn's disease. (Funded by AbbVie; U-EXCEL, U-EXCEED, and U-ENDURE ClinicalTrials.gov numbers, NCT03345849, NCT03345836, and NCT03345823.).


Asunto(s)
Enfermedad de Crohn , Inhibidores de las Cinasas Janus , Humanos , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/tratamiento farmacológico , Herpes Zóster/inducido químicamente , Herpes Zóster/etiología , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Inhibidores de las Cinasas Janus/administración & dosificación , Inhibidores de las Cinasas Janus/efectos adversos , Inhibidores de las Cinasas Janus/uso terapéutico , Neutropenia/inducido químicamente , Neutropenia/etiología , Quimioterapia de Inducción/efectos adversos , Quimioterapia de Inducción/métodos , Quimioterapia de Mantención/efectos adversos , Quimioterapia de Mantención/métodos
2.
J Am Chem Soc ; 146(37): 25755-25763, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39221657

RESUMEN

Complex organic lateral heterostructures (OLHs) with spatial distribution of two or more chemical components are crucial for designing and realizing unique structure-dependent optoelectronic applications. However, the precise design of well-defined OLHs with flexible domain regulation remains a considerable challenge. Herein, we present a stepwise solution self-assembly method to synthesize two-dimensional (2D) OLHs with a central rhombus domain and a lateral region featuring tunable blue and green emission based on the sequential nucleation and growth of 2D crystals. By controlling the initial crystallization time of 2,6-diphenylanthracene, the rhombic length ratio (α) of the multicolor-emissive part of the 2D OLHs is precisely modified. Furthermore, a third lateral layer is constructed on the resulting OLHs, demonstrating scalable lateral regulation. Significantly, these prepared 2D OLHs exhibit great excitation position-dependent waveguide characteristics and enable a 0.06 dB/µm low-loss waveguiding, which are conducive to photon transport and conversion for photonic integrated circuits. This work provides a stepwise strategy for the accurate fabrication of 2D OLHs, fabricating the developments of next-generation optoelectronics devices.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39326583

RESUMEN

BACKGROUND & AIMS: Efficacy of upadacitinib, an oral Janus kinase inhibitor, for moderate-to-severe Crohn's disease was demonstrated in phase 3 induction (U-EXCEL, U-EXCEED) and maintenance (U-ENDURE) trials; this post hoc analysis evaluated upadacitinib outcomes in patients with fistulizing disease in these studies. METHODS: Patients were randomized (2:1) to once-daily upadacitinib 45 mg (UPA45) or placebo for 12 weeks. UPA45 clinical responders were rerandomized (1:1:1) to upadacitinib 15 mg (UPA15), 30 mg (UPA30), or placebo for 52 weeks. In patients with fistulas (any and perianal), resolution of drainage, closure of external openings, clinical remission, endoscopic response, and safety were assessed. RESULTS: Of 1021 patients in U-EXCEL and U-EXCEED, 143 (14.0%) had any fistulas at baseline (66 draining); of these, most (128) had perianal fistulas (56 draining). Greater proportions of patients receiving upadacitinib vs placebo achieved resolution of drainage of perianal fistulas at the end of induction (placebo, 5.6%, n/N = 1/18; UPA45, 44.7%, n/N = 17/38; P = .003) and maintenance (placebo, 0%, n/N = 0/11; UPA15, 28.6%, n/N = 4/14; P = .105; UPA30, 23.1% n/N = 3/13; P = .223) and closure of perianal fistula external openings (induction: placebo, 4.8%, n/N = 2/42; UPA45, 22.1%, n/N = 19/86; P = .013; maintenance: placebo, 0%, n/N = 0/30; UPA15, 18.8%, n/N = 6/32; P = .024; UPA30, 16.0%, n/N = 4/25; P = .037). CONCLUSION: Patients with fistulizing disease (primarily perianal) treated with upadacitinib achieved higher rates of resolution of drainage, closure of external openings, clinical remission, and endoscopic response vs placebo. CLINICALTRIALS: gov numbers: U-EXCEL (NCT03345849), U-EXCEED (NCT03345836), U-ENDURE (NCT03345823).

4.
Anal Chem ; 96(2): 847-855, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38159051

RESUMEN

RNA molecules undergo various chemical modifications that play critical roles in a wide range of biological processes. N6,N6-Dimethyladenosine (m6,6A) is a conserved RNA modification and is essential for the processing of rRNA. To gain a deeper understanding of the functions of m6,6A, site-specific and accurate quantification of this modification in RNA is indispensable. In this study, we developed an AlkB-facilitated demethylation (AD-m6,6A) method for the site-specific detection and quantification of m6,6A in RNA. The N6,N6-dimethyl groups in m6,6A can cause reverse transcription to stall at the m6,6A site, resulting in truncated cDNA. However, we found that Escherichia coli AlkB demethylase can effectively demethylate m6,6A in RNA, generating full-length cDNA from AlkB-treated RNA. By quantifying the amount of full-length cDNA produced using quantitative real-time PCR, we were able to achieve site-specific detection and quantification of m6,6A in RNA. Using the AD-m6,6A method, we successfully detected and quantified m6,6A at position 1851 of 18S rRNA and position 937 of mitochondrial 12S rRNA in human cells. Additionally, we found that the level of m6,6A at position 1007 of mitochondrial 12S rRNA was significantly reduced in lung tissues from sleep-deprived mice compared with control mice. Overall, the AD-m6,6A method provides a valuable tool for easy, accurate, quantitative, and site-specific detection of m6,6A in RNA, which can aid in uncovering the functions of m6,6A in human diseases.


Asunto(s)
Proteínas de Escherichia coli , ARN , Humanos , Animales , Ratones , ARN/química , Adenosina/química , ADN Complementario , Metilación , Escherichia coli/genética , Escherichia coli/metabolismo , Desmetilación , Oxigenasas de Función Mixta
5.
Small ; : e2407848, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39439184

RESUMEN

Over the last decades, notable progress is achieved in (K, Na)NbO3 (KNN)-based lead-free piezoceramics. However, more studies are conducted to increase its piezoelectric charge coefficient (d33). For actuator applications, piezoceramics need high electric-field induced strain under low electric fields while maintaining exceptional temperature stability across a wide temperature range. In this study, this work developes Li/Sb-codoped KNN (LKNNS) ceramics with high electrostrain by defect engineering and domain engineering. A remarkable strain of 0.43%, along with a giant d33* value of 2177 pm V-1, is attained in the LKNNS ceramic at 20 kV cm-1. The ceramic exhibits a minimal performance decrease of less than 15% over a temperature range from room temperature to 150 °C. The exceptional strain is attributed to the presence of A-site vacancy-oxygen vacancy ( V A ' - V O • • ${\mathrm{V}}_{\mathrm{A}}^{{\prime}}{\mathrm{ - V}}_{\mathrm{O}}^{{\mathrm{ \bullet \bullet }}}$ ) defect dipoles and the increase in nano-domains. The hierarchical domain configuration and V A ' - V O • • ${\mathrm{V}}_{\mathrm{A}}^{{\prime}}{\mathrm{ - V}}_{\mathrm{O}}^{{\mathrm{ \bullet \bullet }}}$ defect dipoles impede the switched domains from reverting to their original state as temperature increases, furthermore, the elongated dipole moments of V A ' - V O • • ${\mathrm{V}}_{\mathrm{A}}^{{\prime}}{\mathrm{ - V}}_{\mathrm{O}}^{{\mathrm{ \bullet \bullet }}}$ caused by rising temperatures compensate for strain reduction results in exceptional temperature stability. This study provides a model for designing piezoelectric materials with exceptional overall performance under low electric fields and across a wide temperature range.

6.
Org Biomol Chem ; 22(31): 6352-6361, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39044718

RESUMEN

Mechanisms for the Csp-H silylation between prop-2-yn-1-ylcyclohexane and triethylsilane, catalyzed by MOH/MH (M = Na or K), were investigated at the M06-L-D3/ma-def2-TZVP level. The SMD model was applied to simulate the solvent effect of 1,2-dimethoxyethane (DME). Computational results suggested that the Csp-H activation of prop-2-yn-1-ylcyclohexane could be achieved by MOH to generate R-CC-M compounds, which continued to react with triethylsilane to yield the final product: (3-cyclohexylprop-1-yn-1-yl) triethylsilane. Moreover, analysis of the Gibbs free energy surface of the three reactions suggested that a path with the participation of LiOH had the highest energy barrier, which was consistent with experimental results showing that only a small amount of product had been formed. The obtained KH could interact readily with the H2O molecule with a much lower energy barrier (0.6 kcal mol-1) than that using the path with prop-2-yn-1-ylcyclohexane. Furthermore, compared to MOH, MH could catalyze the reaction with lower energy barriers, and the reactions became exothermic, thereby benefiting the reaction. Finally, the mechanism for obtaining the byproduct (prop-1-yn-1-ylcyclohexane) was posited: it had a higher energy barrier than the path to yield the main product. Frontier orbital, noncovalent interactions (NCI), Fukui function and dual descriptor analyses could be used to analyze the structure and reveal the reaction substances.

7.
J Fluoresc ; 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38460097

RESUMEN

A novel nanocomposite fluorescent probe consisting of quantum dots and a silica molecularly imprinted polymer (MIPs-capped ZnS:Mn QDs) was synthesized and applied for the rapid detection of teflubenzuron (TBZ) based on the fluorescence quenching of a composite probe via TBZ. The fluorescence quenching efficiency of MIP@SiO2@ZnS:Mn QDs displayed a linear relationship over the concentration range of 0-26.24 µmol/L with a correlation coefficient of 0.9857 and the limit of detection was 2.4 µg/L. The selectivity test showed that the nanocomposite had good selectively rebind TBZ with higher imprinting factor of 3.06 compared with four structurally similar compounds. In addition, the probe was successfully applied to the detection of TBZ in vegetable samples with a recovery of 90.3~97.1% and with a relative standard deviation below 3.2%. This developed method has the advantages of simple preparation, fast response and low toxicity for trace TBZ detection.

8.
Acta Pharmacol Sin ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160244

RESUMEN

Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease characterized by unremitting pulmonary myofibroblasts activation, extracellular matrix (ECM) deposition and inflammatory recruitment. PF has no curable medication yet. In this study we investigated the molecular pathogenesis and potential therapeutic targets of PF and discovered drug lead compounds for PF therapy. A murine PF model was established in mice by intratracheal instillation of bleomycin (BLM, 5 mg/kg). We showed that the protein level of pulmonary protein phosphatase magnesium-dependent 1A (PPM1A, also known as PP2Cα) was significantly downregulated in PF patients and BLM-induced PF mice. We demonstrated that TRIM47 promoted ubiquitination and decreased PPM1A protein in PF progression. By screening the lab in-house compound library, we discovered otilonium bromide (OB, clinically used for treating irritable bowel syndrome) as a PPM1A enzymatic activator with an EC50 value of 4.23 µM. Treatment with OB (2.5, 5 mg·kg-1·d-1, i.p., for 20 days) significantly ameliorated PF-like pathology in mice. We constructed PF mice with PPM1A-specific knockdown in the lung tissues, and determined that by targeting PPM1A, OB treatment suppressed ECM deposition through TGF-ß/SMAD3 pathway in fibroblasts, repressed inflammatory responses through NF-κB/NLRP3 pathway in alveolar epithelial cells, and blunted the crosstalk between inflammation in alveolar epithelial cells and ECM deposition in fibroblasts. Together, our results demonstrate that pulmonary PPM1A activation is a promising therapeutic strategy for PF and highlighted the potential of OB in the treatment of the disease.

9.
Acta Pharmacol Sin ; 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39384887

RESUMEN

p53, a tumor suppressor protein, has a vital role in the regulation of the cell cycle, apoptosis, and DNA damage repair. The degradation of p53 is predominantly controlled by the murine double minute 2 (MDM2) protein, a ubiquitin E3 ligase. The overexpression or amplification of MDM2 is commonly observed in various human cancers bearing wild-type p53 alleles, leading to the rapid degradation of the p53 protein and the attenuation of p53 tumor suppression functions. Thus, a major effort in p53-based cancer therapy has been to research MDM2 antagonists that specifically stabilize and activate p53, leading to the suppression of tumor growth. However, despite numerous efforts to develop MDM2 antagonists, to date they have failed to reach clinical use, largely because of the cytotoxicity associated with these small molecules. This study used our newly designed structure-based virtual screening approach on a commercial compound library to identify a novel compound, CGMA-Q18, which directly binds to MDM2, leading to the activation of p53, the induction of apoptosis, and cell cycle arrest in cancer cells. Notably, CGMA-Q18 significantly inhibited tumor xenograft growth in nude mice without observable toxicity. These findings highlight our useful virtual screening protocol and CGMA-Q18 as a putative MDM2 antagonist.

10.
BMC Pediatr ; 24(1): 136, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383331

RESUMEN

OBJECTIVE: To explore the effect of repetitive transcranial magnetic stimulation (rTMS)-assisted training on lower limb motor function in children with hemiplegic cerebral palsy (HCP). METHOD: Thirty-one children with HCP who met the inclusion criteria were selected and randomly divided into a control group (n = 16) and an experimental group (n = 15). The control group received routine rehabilitation treatment for 30 min each time, twice a day, 5 days a week for 4 weeks. Based on the control group, the experimental group received rTMS for 20 min each time, once a day, 5 days a week for 4 weeks. The outcome measures included a 10-metre walk test (10MWT), a 6-minute walk distance (6MWD) test, D- and E-zone gross motor function measurements (GMFM), the symmetry ratio of the step length and stance time and the muscle tone of the triceps surae and the hamstrings (evaluated according to the modified Ashworth scale), which were obtained in both groups of children before and after treatment. RESULTS: After training, the 10MWT (P < 0.05), 6MWD (P < 0.01), GMFM (P < 0.001) and the symmetry ratio of the step length and stance time of the two groups were significantly improved (P < 0.05), there was more of an improvement in the experimental group compared with the control group. There was no significant change in the muscle tone of the hamstrings between the two groups before and after treatment (P > 0.05). After treatment, the muscle tone of the triceps surae in the experimental group was significantly reduced (P < 0.05), but there was no significant change in the control group (P > 0.05). CONCLUSION: Repetitive TMS-assisted training can improve lower limb motor function in children with HCP.


Asunto(s)
Parálisis Cerebral , Estimulación Magnética Transcraneal , Niño , Humanos , Hemiplejía/etiología , Extremidad Inferior , Caminata
11.
Hepatobiliary Pancreat Dis Int ; 23(5): 472-480, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38724321

RESUMEN

BACKGROUND: Regulatory B cells (Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs (miRNAs), miR-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and miR-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs (mBregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. METHODS: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce miR-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. RESULTS: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of mBregs in the circulating blood were significantly impaired. miR-29a-3p was found to be a regulator of mBregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5 (NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of mBregs. The inhibition of miR-29a-3p in CD19+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into mBregs. In addition, the observed enhancement of differentiation and immunosuppressive function of mBregs upon miR-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. CONCLUSIONS: miR-29a-3p was found to be a crucial regulator for mBregs differentiation and immunosuppressive function. Silencing miR-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.


Asunto(s)
Antígenos CD19 , Linfocitos B Reguladores , Antígeno CD24 , Diferenciación Celular , Trasplante de Hígado , MicroARNs , Humanos , MicroARNs/metabolismo , MicroARNs/genética , Linfocitos B Reguladores/inmunología , Linfocitos B Reguladores/metabolismo , Antígenos CD19/metabolismo , Antígenos CD19/genética , Masculino , Antígeno CD24/metabolismo , Antígeno CD24/genética , Transducción de Señal , Rechazo de Injerto/inmunología , Rechazo de Injerto/genética , Femenino , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Persona de Mediana Edad , Tolerancia Inmunológica , Células Cultivadas , Adulto , Fenotipo , Memoria Inmunológica
12.
J Am Chem Soc ; 145(40): 22232-22242, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37772932

RESUMEN

N4-Acetylcytidine (ac4C) has been found to affect a variety of cellular and biological processes. For a mechanistic understanding of the roles of ac4C in biology and disease, we present an antibody-free, fluorine-assisted metabolic sequencing method to detect RNA ac4C, called "FAM-seq". We successfully applied FAM-seq to profile ac4C landscapes in human 293T, HeLa, and MDA cell lines in parallel with the reported acRIP-seq method. By comparison with the classic ac4C antibody sequencing method, we found that FAM-seq is a convenient and reliable method for transcriptome-wide mapping of ac4C. Because this method holds promise for detecting nascent RNA ac4C modifications, we further investigated the role of ac4C in regulating chemotherapy drug resistance in chronic myeloid leukemia. The results indicated that drug development or combination therapy could be enhanced by appreciating the key role of ac4C modification in cancer therapy.

13.
J Mol Evol ; 91(1): 60-75, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36576533

RESUMEN

Reduced oxidation state phosphorus compounds may have been brought to the early Earth via meteorites or could have formed through geologic processes. These compounds could have played a role in the origin of biological phosphorus (P, hereafter) compounds. Reduced oxidation state P compounds are generally more soluble in water and are more reactive than orthophosphate and its associated minerals. However, to date no facile routes to generate C-O-P type compounds using reduced oxidation state P compounds have been reported under prebiotic conditions. In this study, we investigate the reactions between reduced oxidation state P compounds-and their oxidized products generated via Fenton reactions-with the nucleosides uridine and adenosine. The inorganic P compounds generated via Fenton chemistry readily react with nucleosides to produce organophosphites and organophosphates, including phosphate diesters via one-pot syntheses. The reactions were facilitated by NH4+ ions and urea as a condensation agent. We also present the results of the plausible stability of the organic compounds such as adenosine in an environment containing an abundance of H2O2. Such results have direct implications on finding organic compounds in Martian environments and other rocky planets (including early Earth) that were richer in H2O2 than O2. Finally, we also suggest a route for the sink of these inorganic P compounds, as a part of a plausible natural P cycle and show the possible formation of secondary phosphate minerals such as struvite and brushite on the early Earth.


Asunto(s)
Marte , Compuestos Organofosforados , Compuestos Organofosforados/química , Medio Ambiente Extraterrestre , Peróxido de Hidrógeno , Minerales/química , Fosfatos/química , Nucleósidos , Adenosina
14.
Angew Chem Int Ed Engl ; 62(45): e202312803, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37698174

RESUMEN

Despite widespread use of the deuterium isotope effect, selective deuterium labeling of chemical molecules remains a major challenge. Herein, a facile and general electrochemically driven, organic mediator enabled deuteration of styrenes with deuterium oxide (D2 O) as the economical deuterium source was reported. Importantly, this transformation could be suitable for various electron rich styrenes mediated by triphenylphosphine (TPP). The reaction proceeded under mild conditions without transition-metal catalysts, affording the desired products in good yields with excellent D-incorporation (D-inc, up to >99 %). Mechanistic investigations by means of isotope labeling experiments and cyclic voltammetry tests provided sufficient support for this transformation. Notably, this method proved to be a powerful tool for late-stage deuteration of biorelevant compounds.

15.
Angew Chem Int Ed Engl ; 62(44): e202311941, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37708153

RESUMEN

Herein, an electrochemically driven NiH-catalyzed reductive coupling of alkyl halides and alkyl alkenes for the construction of Csp3 -Csp3 bonds is firstly reported. Notably, alkyl halides serve dual function as coupling substrates and as hydrogen sources to generate NiH species under electrochemical conditions. The tunable nature of this reaction is realized by introducing an intramolecular coordinating group to the substrate, where the product can be easily adjusted to give the desired branched products. The method proceeds under mild conditions, exhibits a broad substrate scope, and affords moderate to excellent yields with over 70 examples, including late-stage modification of natural products and drug derivatives. Mechanistic insights offer evidence for an electrochemically driven coupling process. The sp3 -carbon-halogen bonds can be activated through single electron transfer (SET) by the nickel catalyst in its low valence state, generated by cathodic reduction, and the generation of NiH species from alkyl halides is pivotal to this transformation.

16.
Circulation ; 143(18): 1775-1792, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33660517

RESUMEN

BACKGROUND: The mevalonate pathway generates endogenous cholesterol and intermediates including geranylgeranyl pyrophosphate (GGPP). By reducing GGPP production, statins exert pleiotropic or cholesterol-independent effects. The potential regulation of GGPP homeostasis through dietary intake and the interaction with concomitant statin therapy is unknown. METHODS: We developed a sensitive high-pressure liquid chromatography technique to quantify dietary GGPP and conducted proteomics, qualitative real-time polymerase chain reaction screening, and Western blot to determine signaling cascades, gene expression, protein-protein interaction, and protein membrane trafficking in wild-type and transgenic rats. RESULTS: GGPP contents were highly variable depending on food source that differentially regulated blood GGPP levels in rats. Diets containing intermediate and high GGPP reduced or abolished the effects of statins in rats with hypoxia- and monocrotaline-induced pulmonary hypertension: this was rescuable by methyl-allylthiosulfinate and methyl-allylthiosulfinate-rich garlic extracts. In human pulmonary artery smooth muscle cells treated with statins, hypoxia activated RhoA in an extracellular GGPP-dependent manner. Hypoxia-induced ROCK2 (Rho associated coiled-coil containing protein kinase 2)/Rab10 (Ras-related protein rab-10) signaling was prevented by statin and recovered by exogenous GGPP. The hypoxia-activated RhoA/ROCK2 pathway in rat and human pulmonary artery smooth muscle cells upregulated the expression of Ca2+-sensing receptor (CaSR) and HIMF (hypoxia-induced mitogenic factor), a mechanism attenuated by statin treatment and regained with exogenous GGPP. Rab10 knockdown almost abrogated hypoxia-promoted CaSR membrane trafficking, a process diminished by statin and resumed by exogenous GGPP. Hypoxia-induced pulmonary hypertension was reduced in rats with CaSR mutated at the binding motif of HIMF and the interaction between dietary GGPP and statin efficiency was abolished. In humans fed a high GGPP diet, blood GGPP levels were increased. This abolished statin-lowering effects on plasma GGPP, and also on hypoxia-enhanced RhoA activity of blood monocytes that was rescued by garlic extracts. CONCLUSIONS: There is important dietary regulation of GGPP levels that interferes with the effects of statin therapy in experimental pulmonary hypertension. These observations rely on a key and central role of RhoA-ROCK2 cascade activation and Rab10-faciliated CaSR membrane trafficking with subsequent overexpression and binding of HIMF to CaSR. These findings warrant clinical investigation for the treatment of pulmonary hypertension and perhaps other diseases by combining statin with garlic-derived methyl-allylthiosulfinate or garlic extracts and thus circumventing dietary GGPP variations.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipertensión Pulmonar/tratamiento farmacológico , Fosfatos de Poliisoprenilo/efectos adversos , Animales , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Masculino , Ratas
17.
Phytother Res ; 36(11): 4210-4229, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35859316

RESUMEN

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In China, the Acacia catechu (AC)-Scutellariae Radix (SR) formula has been widely used for pulmonary infection in clinical practice for several centuries. However, the potential role and mechanisms of this formula against COVID-19 remains unclear. The present study was designed to dissect the active ingredients, molecular targets, and the therapeutic mechanisms of AC-SR formula in the treatment of COVID-19 based on a systems pharmacology strategy integrated by ADME screening, target prediction, network analysis, GO and KEGG enrichment analysis, molecular docking, and molecular dynamic (MD) simulations. Finally, Quercetin, Fisetin(1-), kaempferol, Wogonin, Beta-sitosterol, Baicalein, Skullcapflavone II, Stigmasterol were primarily screened to be the potentially effective active ingredients against COVID-19. The hub-proteins were TP53, JUN, ESR1, MAPK1, Akt1, HSP90AA1, TNF, IL-6, SRC, and RELA. The potential mechanisms of AC-SR formula in the treatment of COVID-19 were the TNF signaling pathway, PI3K-Akt signaling pathway and IL-17 signaling pathway, etc. Furthermore, virtual docking revealed that baicalein, (+)-catechin and fisetin(1-) exhibited high affinity to SARS-CoV-2 3CLpro, which has validated by the FRET-based enzymatic inhibitory assays with the IC50 of 11.3, 23.8, and 44.1 µM, respectively. And also, a concentration-dependent inhibition of baicalein, quercetin and (+)-catechin against SARS-CoV-2 ACE2 was observed with the IC50 of 138.2, 141.3, and 348.4 µM, respectively. These findings suggested AC-SR formula exerted therapeutic effects involving "multi-compounds and multi-targets." It might be working through directly inhibiting the virus, improving immune function, and reducing the inflammatory in response to anti-COVID-19. Ultimately, this study would provide new perspective for discovering potential drugs and mechanisms against COVID-19.


Asunto(s)
Acacia , Tratamiento Farmacológico de COVID-19 , Catequina , Medicamentos Herbarios Chinos , Humanos , SARS-CoV-2 , Scutellaria baicalensis , Simulación del Acoplamiento Molecular , Quercetina/farmacología , Quercetina/uso terapéutico , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China
18.
J Environ Manage ; 324: 116355, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36179470

RESUMEN

Understanding how trade between regions or countries drives the transfer of air pollution has attracted considerable interest recently, but few studies have explored the various transfer pathways or evaluated economic losses due to the health impact of such air pollution. Here, we assess the air pollutant emissions and related health impacts and economic losses in China caused by export trade due to US demand by combining the linked multi-regional input-output (MRIO) model, GEOS-Chem model, integrated exposure-response model, and the willingness to pay method. We show that the air pollutant emissions embedded in China's export due to the US demand reached 5792.38 Kt in 2012 (2.48% of the total), which includes direct exports of intermediate (40.27%) and final (33.61%) products and indirect exports of intermediate products via domestic provinces (16.43%, domestic spillover) and other countries (9.69%, foreign spillover). The resulting increase in PM2.5 (<2.8 µg m-3) leads to additional 27,963 deaths in 30 provinces, with a higher death toll in coastal areas and the corresponding economic loss was higher in more developed regions and reached USD 2.08 billion. This study highlights the region-different air pollution and health impacts in China embedded in the US-demand trade, and provides a framework for the analysis of health and economic losses hidden in global trade, particularly between developing and developed countries.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , China , Internacionalidad , Material Particulado/análisis
19.
J Environ Manage ; 323: 116286, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36137457

RESUMEN

Quantifying fossil fuel CO2 (CO2ff) in the atmosphere provides a benchmark method to monitor anthropogenic carbon emissions. Radiocarbon (14C) in atmospheric CO2ff has been widely studied using the 14C in plants to document regional CO2ff patterns. However, annual CO2ff variations, reflecting spatial distributions based on plant samples, are still scarce. In this paper, the spatial distribution and temporal CO2ff changes in the Guanzhong Basin is established using Δ14C measurements from maize leaves collected in 2011 and 2012. With regard to spatial distribution, samples collected around Xi'an City showed lower Δ14C values (more CO2ff), while sites located near the perimeter of the basin showed higher Δ14C values (less CO2ff). This is likely due to the concentration of anthropogenic activities in the center of the Guanzhong Basin. The observed CO2ff mole fractions generally matched with PKU CO2 inventory and the ODIAC CO2 inventory data in the spatial distribution trend. However, it seems that thermal power plants were not well captured by the PKU CO2 inventory. Our results provide useful information for the improvement of the inventory and verification of regional carbon cycle models.


Asunto(s)
Contaminantes Atmosféricos , Combustibles Fósiles , Contaminantes Atmosféricos/análisis , Carbono , Dióxido de Carbono/análisis , China , Monitoreo del Ambiente/métodos , Combustibles Fósiles/análisis , Zea mays , Radioisótopos de Carbono
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(4): 626-636, 2022 Jul.
Artículo en Zh | MEDLINE | ID: mdl-35871733

RESUMEN

Objective: To study the correlation between N 6-methyladenosine (m 6A)-modification-associated long non-coding RNAs (lncRNAs) and poor prognosis and immunotherapy in cervical cancer based on data mining of The Cancer Genome Atlas (TCGA) cervical cancer dataset, so as to assess effectively the prognosis of cervical cancer patients and the feasibility of immunotherapy. Methods: We identified m 6A-modification-associated lncRNAs correlated to the prognosis of cervical cancer by conducting bioinformatics analysis of cervical cancer samples from the TCGA datasets and constructed a prognostic risk model of cervical cancer accordingly. Results: A total of 343 m 6A-modification-associated lncRNAs were identified from the samples of 304 cervical cancer patients. Univariate Cox regression analysis showed that 26 out of the 343 m 6A-modification-associated lncRNAs were significantly associated with the prognosis of cervical cancer patients. We identified 7 m 6A-modification-associated lncRNAs, including DLEU1, AC099850.4, DDN-AS1, EP300-AS1, AC131159.1, AL441992.2, and AL021707.6 through Lasso regression analysis and then developed a prognostic risk model based on them. According to the Kaplan-Meier survival analysis, cervical cancer patients in the low-risk group exhibited significantly improved overall survival (OS) in comparison with those in the high-risk group ( P<0.001). The area under the curve ( AUC) of receiver operating characteristic (ROC) curve analysis demonstrated the high sensitivity and credibility of the risk model. Multivariate Cox analysis showed that the risk score was an independent prognostic factor of cervical cancer patients. Tumor immune dysfunction and exclusion (TIDE) analysis predicted that the high-risk group would benefit more from immunotherapy. In addition, we found that immune checkpoint PD1 was associated with the expression of m6A-modification-related lncRNAs such as DDN-AS1, and the expression was higher in the high-risk group ( P<0.05). Conclusion: The prognostic risk model constructed on the basis of the aforementioned 7 m 6A-modification-associated lncRNAs can be used to effectively predict the prognosis of cervical cancer patients and assess the efficacy of immunotherapy targeting PD1.


Asunto(s)
ARN Largo no Codificante , Neoplasias del Cuello Uterino , Biomarcadores de Tumor , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunoterapia , Pronóstico , ARN Largo no Codificante/genética , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/terapia
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