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1.
J Physiol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953534

RESUMO

The central histaminergic system has a pivotal role in emotional regulation and psychiatric disorders, including anxiety, depression and schizophrenia. However, the effect of histamine on neuronal activity of the centrolateral amygdala (CeL), an essential node for fear and anxiety processing, remains unknown. Here, using immunostaining and whole-cell patch clamp recording combined with optogenetic manipulation of histaminergic terminals in CeL slices prepared from histidine decarboxylase (HDC)-Cre rats, we show that histamine selectively suppresses excitatory synaptic transmissions, including glutamatergic transmission from the basolateral amygdala, on both PKC-δ- and SOM-positive CeL neurons. The histamine-induced effect is mediated by H3 receptors expressed on VGLUT1-/VGLUT2-positive presynaptic terminals in CeL. Furthermore, optoactivation of histaminergic afferent terminals from the hypothalamic tuberomammillary nucleus (TMN) also significantly suppresses glutamatergic transmissions in CeL via H3 receptors. Histamine neither modulates inhibitory synaptic transmission by presynaptic H3 receptors nor directly excites CeL neurons by postsynaptic H1, H2 or H4 receptors. These results suggest that histaminergic afferent inputs and presynaptic H3 heteroreceptors may hold a critical position in balancing excitatory and inhibitory synaptic transmissions in CeL by selective modulation of glutamatergic drive, which may not only account for the pathophysiology of psychiatric disorders but also provide potential psychotherapeutic targets. KEY POINTS: Histamine selectively suppresses the excitatory, rather than inhibitory, synaptic transmissions on both PKC-δ- and SOM-positive neurons in the centrolateral amygdala (CeL). H3 receptors expressed on VGLUT1- or VGLUT2-positive afferent terminals mediate the suppression of histamine on glutamatergic synaptic transmission in CeL. Optogenetic activation of hypothalamic tuberomammillary nucleus (TMN)-CeL histaminergic projections inhibits glutamatergic transmission in CeL via H3 receptors.

2.
J Am Chem Soc ; 146(11): 7210-7215, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38437461

RESUMO

Transition metal-catalyzed reductive cross-couplings to build C-C/Si bonds have been developed, but the reductive cross-coupling to create the C(sp2)-B bond has not been explored. Herein, we describe a nickel-catalyzed reductive cross-coupling between aryl halides and bromoboranes to construct a C(sp2)-B bond. This protocol offers a convenient approach for the synthesis of a wide range of aryl boronate esters, using readily available starting materials. Mechanistic studies indicate that the key to the success of the reaction is the activation of the B-Br bond of bromoboranes with a Lewis base such as 2-MeO-py. The activation ensures that bromoboranes will react with the active nickel(I) catalyst prior to aryl halides, which is different from the sequence of the general nickel-catalyzed reductive C(sp2)-C/Si cross-coupling, where the oxidative addition of an aryl halide proceeds first. Notably, this approach minimizes the production of undesired homocoupling byproduct without the requirement of excessive quantities of either substrate.

3.
J Am Chem Soc ; 146(38): 26574-26584, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39264946

RESUMO

The ligated boryl radical (LBR) has emerged as a potent tool for activating alkyl halides in radical transformations through halogen-atom transfer (XAT). However, unactivated alkyl chlorides still present an open challenge for this strategy. We herein describe a new activation mode of the LBR for the activation of unactivated alkyl chlorides to construct a C(sp3)-C(sp3) bond. Mechanistic studies reveal that the success of the protocol relies on a radical replacement process between the LBR and unactivated alkyl chloride, forming an alkyl borane intermediate as the alkyl radical precursor. Aided with the additive K3PO4, the alkyl borane then undergoes one-electron oxidation, generating an alkyl radical. The incorporation of the radical replacement activation model to activate unactivated alkyl chlorides significantly enriches LBR chemistry, which has been applied to activate alkyl iodides, alkyl bromides, and activated alkyl chlorides via XAT.

4.
J Am Chem Soc ; 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39473165

RESUMO

ß-Fluoromethyl (CH2F, CHF2, and CF3)-substituted chiral ketones are essential moieties and are vital building blocks in pharmaceutical and agrochemistry. However, general and convenient methods for enantio-diverse access to diverse ß-fluoromethylated ketones are lacking, hindering the further development of these functional moieties. In this study, we developed an ene-reductase-based photobiocatalytic platform for efficient synthesis of enantio-divergent ß-fluoromethylated chiral ketones. Our method highlights substrate-type diversity, excellent enantioselectivity, enzymatic enantio-divergent synthesis, as well as a dicyanopyrazine (DPZ)-type photosensitizer for biocompatible olefin E/Z isomerization in enzymatic stereoconvergent olefin asymmetric reduction, thereby providing a general photobiocatalytic solution to diverse ß-fluoromethylated chiral ketones.

5.
Chemistry ; 30(18): e202303857, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38205617

RESUMO

The methods for the cross-coupling of aryl(trialkyl)silanes are long-standing challenges due to the extreme inertness of C-Si(R3) bond, though the reaction is environmentally friendly and highly regioselective to synthesize biaryls. Herein, we report a copper-catalyzed cross-coupling of aryl(trialkyl)silanes and aryl via a radical mechanism. The reaction proceeds efficiently with aryl sulfonium salts as limiting reagents, exhibits broad substrate scope, and provides an important synthetic strategy to acquire biaryls, exemplified by unsymmetrical fluorescence probes and late-stage functionalization of drugs. Of note, the experimental and theoretical mechanistic studies revealed a radical mechanism where the copper catalyst and CsF play critical roles on the radical generation and desilylation process.

6.
Acta Pharmacol Sin ; 45(7): 1451-1465, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38491161

RESUMO

Inflammatory bowel disease (IBD) is characterized by persistent damage to the intestinal barrier and excessive inflammation, leading to increased intestinal permeability. Current treatments of IBD primarily address inflammation, neglecting epithelial repair. Our previous study has reported the therapeutic potential of notoginsenoside R1 (NGR1), a characteristic saponin from the root of Panax notoginseng, in alleviating acute colitis by reducing mucosal inflammation. In this study we investigated the reparative effects of NGR1 on mucosal barrier damage after the acute injury stage of DSS exposure. DSS-induced colitis mice were orally treated with NGR1 (25, 50, 125 mg·kg-1·d-1) for 10 days. Body weight and rectal bleeding were daily monitored throughout the experiment, then mice were euthanized, and the colon was collected for analysis. We showed that NGR1 administration dose-dependently ameliorated mucosal inflammation and enhanced epithelial repair evidenced by increased tight junction proteins, mucus production and reduced permeability in colitis mice. We then performed transcriptomic analysis on rectal tissue using RNA-sequencing, and found NGR1 administration stimulated the proliferation of intestinal crypt cells and facilitated the repair of epithelial injury; NGR1 upregulated ISC marker Lgr5, the genes for differentiation of intestinal stem cells (ISCs), as well as BrdU incorporation in crypts of colitis mice. In NCM460 human intestinal epithelial cells in vitro, treatment with NGR1 (100 µM) promoted wound healing and reduced cell apoptosis. NGR1 (100 µM) also increased Lgr5+ cells and budding rates in a 3D intestinal organoid model. We demonstrated that NGR1 promoted ISC proliferation and differentiation through activation of the Wnt signaling pathway. Co-treatment with Wnt inhibitor ICG-001 partially counteracted the effects of NGR1 on crypt Lgr5+ ISCs, organoid budding rates, and overall mice colitis improvement. These results suggest that NGR1 alleviates DSS-induced colitis in mice by promoting the regeneration of Lgr5+ stem cells and intestinal reconstruction, at least partially via activation of the Wnt/ß-Catenin signaling pathway. Schematic diagram of the mechanism of NGR1 in alleviating colitis. DSS caused widespread mucosal inflammation epithelial injury. This was manifested by the decreased expression of tight junction proteins, reduced mucus production in goblet cells, and increased intestinal permeability in colitis mice. Additionally, Lgr5+ ISCs were in obviously deficiency in colitis mice, with aberrant down-regulation of the Wnt/ß-Catenin signaling. However, NGR1 amplified the expression of the ISC marker Lgr5, elevated the expression of genes associated with ISC differentiation, enhanced the incorporation of BrdU in the crypt and promoted epithelial restoration to alleviate DSS-induced colitis in mice, at least partially, by activating the Wnt/ß-Catenin signaling pathway.


Assuntos
Colite , Ginsenosídeos , Mucosa Intestinal , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas G , Via de Sinalização Wnt , Animais , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Via de Sinalização Wnt/efeitos dos fármacos , Colite/tratamento farmacológico , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Humanos
7.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34772807

RESUMO

Chronic infection with liver flukes (such as Clonorchis sinensis) can induce severe biliary injuries, which can cause cholangitis, biliary fibrosis, and even cholangiocarcinoma. The release of extracellular vesicles by C. sinensis (CsEVs) is of importance in the long-distance communication between the hosts and worms. However, the biological effects of EVs from liver fluke on biliary injuries and the underlying molecular mechanisms remain poorly characterized. In the present study, we found that CsEVs induced M1-like activation. In addition, the mice that were administrated with CsEVs showed severe biliary injuries associated with remarkable activation of M1-like macrophages. We further characterized the signatures of miRNAs packaged in CsEVs and identified a miRNA Csi-let-7a-5p, which was highly enriched. Further study showed that Csi-let-7a-5p facilitated the activation of M1-like macrophages by targeting Socs1 and Clec7a; however, CsEVs with silencing Csi-let-7a-5p showed a decrease in proinflammatory responses and biliary injuries, which involved in the Socs1- and Clec7a-regulated NF-κB signaling pathway. Our study demonstrates that Csi-let-7a-5p delivered by CsEVs plays a critical role in the activation of M1-like macrophages and contributes to the biliary injuries by targeting the Socs1- and Clec7a-mediated NF-κB signaling pathway, which indicates a mechanism contributing to biliary injuries caused by fluke infection. However, molecules other than Csi-let-7a-5p from CsEVs that may also promote M1-like polarization and exacerbate biliary injuries are not excluded.


Assuntos
Vesículas Extracelulares/metabolismo , Fasciola hepatica/metabolismo , Macrófagos/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Infecção Persistente/parasitologia , Transdução de Sinais/fisiologia
8.
Zhongguo Zhong Yao Za Zhi ; 49(15): 4128-4138, 2024 Aug.
Artigo em Zh | MEDLINE | ID: mdl-39307745

RESUMO

The mechanism of alleviating bleomycin-induced pulmonary fibrosis in mice was compared between Qingqiao(Forsythiae Fructus produced with immature fruits) and Laoqiao(Forsythiae Fructus produced with mature fruits) from the pharmacodynamic correlation and composition differences. Mice were randomized into normal, model, pirfenidone(50 mg·kg~(-1)), low-and high-dose(1.3, 2.6 g·kg~(-1), respectively) Qingqiao, and low-and high-dose(1.3, 2.6 g·kg~(-1), respectively) Laoqiao groups. The mouse model of pulmonary fibrosis was established by intratracheal instillation of bleomycin, during which the survival rate and body weight changes of the mice were measured. After modeling, the lung index was calculated, and the pathological changes in the lung tissue were evaluated by hematoxylin-eosin(HE), Masson, and Sirius red staining. Transmission electron microscopy was employed to observe the ultrastructure of the lung tissue. The biochemical assay was employed to measure the levels of transforming growth factor-ß1(TGF-ß1), α-smooth muscle actin(α-SMA), E-cadherin, and hydroxyproline(HYP) in the lung tissue and interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in the bronchoalveolar lavage fluid(BALF). The mRNA and protein levels of matrix metalloproteinase 7(MMP7), collagen Ⅰ, E-cadherin, TNF-α, vimentin, TGF-ß1, and α-SMA in the lung tissue were determined by RT-qPCR and Western blot, respectively. The expression of α-SMA in the lung tissue was detected by the immunofluorescence assay. Principal component analysis was performed to compare the effects of Qingqiao and Laoqiao in ameliorating pulmonary fibrosis. Molecular docking was employed to analyze the binding between the compounds with high content in Laoqiao and TGF-ß1. The cell-counting kit(CCK-8) assay was used to examine the effects of the active compounds on TGF-ß1-induced BEAS-2B and HFL1 cell models. The results showed that Qingqiao and Laoqiao increased the survival rate, reduced the lung index, alleviated the pathological damage and collagen deposition in the lung tissue, ameliorated the damage of lamellar bodies in alveolar epithelial type Ⅱ cells, lowered the level of IL-6 and TNF-α in the BALF, down-regulated the expression of HYP, MMP7, vimentin, collagen Ⅰ, TGF-ß1, and α-SMA, and up-regulated the expression of E-cadherin in the lung tissue of the mouse model of pulmonary fibrosis. The collagen deposition in the mouse model of pulmonary fibrosis was comprehensively evaluated by principal component analysis, and the effects of different treatments followed the trend of high-dose Laoqiao>low-dose Laoqiao>high-dose Qingqiao>low-dose Qingqiao. Molecular docking showed that hydroxytyrosol, caffeic acid, phillygenin, and(-)-lariciresinol had strong binding affinity with TGF-ß1 receptor. The results of cell experiments showed that these compounds significantly attenuated the TGF-ß1-induced damage in BEAS-2B cells and inhibited the TGF-ß1-induced proliferation of HFL1 cells. In conclusion, both Qingqiao and Laoqiao were effective in ameliorating bleomycin-induced pulmonary fibrosis in mice. Laoqiao was superior to Qingqiao in reducing collagen deposition, which might be attributed to the higher content of hydroxytyrosol, caffeic acid, phillygenin, and(-)-lariciresinol in Laoqiao than in Qingqiao.


Assuntos
Bleomicina , Medicamentos de Ervas Chinesas , Fibrose Pulmonar , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/genética , Camundongos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Masculino , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Humanos , Actinas/genética , Actinas/metabolismo
9.
Zhongguo Zhong Yao Za Zhi ; 48(20): 5612-5622, 2023 Oct.
Artigo em Zh | MEDLINE | ID: mdl-38114154

RESUMO

This study aims to investigate the intervention effect of the aqueous extract of Epimedium sagittatum Maxim on the mouse model of bleomycin(BLM)-induced pulmonary fibrosis, so as to provide data support for the clinical treatment of pulmonary fibrosis. Ninety male C57BL/6N mice were randomized into normal(n=10), model(BLM, n=20), pirfenidone(PFD, 270 mg·kg~(-1), n=15), and low-, medium-, and high-dose E. sagittatum extract(1.67 g·kg~(-1), n=15; 3.33 g·kg~(-1), n=15; 6.67 g·kg~(-1), n=15) groups. The model of pulmonary fibrosis was established by intratracheal instillation of BLM(5 mg·kg~(-1)) in the other five groups except the normal group, which was treated with an equal amount of normal saline. On the day following the modeling, each group was treated with the corresponding drug by gavage for 21 days. During this period, the survival rate of the mice was counted. After gavage, the lung index was calculated, and the morphology and collagen deposition of the lung tissue were observed by hematoxylin-eosin(HE) and Masson staining, respectively. The levels of reactive oxygen species(ROS) in lung cell suspensions were measured by flow cytometry. The levels of glutathione peroxidase(GSH-Px), total superoxide dismutase(T-SOD), and malondialdehyde(MDA) the in lung tissue were measured. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling(TUNEL) was employed to examine the apoptosis of lung tissue cells. The content of interleukin-6(IL-6), chemokine C-C motif ligand 2(CCL-2), matrix metalloproteinase-8(MMP-8), transforming growth factor-beta 1(TGF-ß1), alpha-smooth muscle actin(α-SMA), E-cadherin, collagen Ⅰ, and fibronectin in the lung tissue was measured by enzyme-linked immunosorbent assay(ELISA). The expression levels of F4/80, Ly-6G, TGF-ß1, and collagen Ⅰ in the lung tissue were determined by immunohistochemistry. The mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue were determined by qRT-PCR. The content of hydroxyproline(HYP) in the lung tissue was determined by alkaline hydrolysation. The expression of α-SMA and E-cadherin was detected by immunofluorescence, and the protein levels of α-SMA, vimentin, E-cadherin in the lung tissue were determined by Western blot. The results showed the aqueous extract of E. sagittatum increased the survival rate, decreased the lung index, alleviated the pathological injury, collagen deposition, and oxidative stress in the lung tissue, and reduced the apoptotic cells. Furthermore, the aqueous extract of E. sagittatum down-regulated the protein levels of F4/80 and Ly-6G and the mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue, reduced the content of IL-6, CCL-2, and MMP-8 in the alveolar lavage fluid. In addition, it lowered the levels of HYP, TGF-ß1, α-SMA, collagen Ⅰ, fibronectin, and vimentin, and elevated the levels of E-cadherin in the lung tissue. The aqueous extract of E. sagittatum can inhibit collagen deposition, alleviate oxidative stress, and reduce inflammatory response by regulating the expression of the molecules associated with epithelial-mesenchymal transition, thus alleviating the symptoms of bleomycin-induced pulmonary fibrosis in mice.


Assuntos
Epimedium , Fibrose Pulmonar , Camundongos , Masculino , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Epimedium/metabolismo , Fibronectinas/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/farmacologia , Metaloproteinase 7 da Matriz/uso terapêutico , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 8 da Matriz/farmacologia , Metaloproteinase 8 da Matriz/uso terapêutico , Vimentina/metabolismo , Interleucina-6/metabolismo , Camundongos Endogâmicos C57BL , Pulmão , Colágeno/metabolismo , Bleomicina/toxicidade , RNA Mensageiro/metabolismo , Caderinas/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2480-2489, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-37282877

RESUMO

Qualitative and quantitative analysis of 2-(2-phenylethyl) chromones in sodium chloride(NaCl)-treated suspension cells of Aquilaria sinensis was conducted by UPLC-Q-Exactive-MS and UPLC-QQQ-MS/MS. Both analyses were performed on a Waters T3 column(2.1 mm×50 mm, 1.8 µm) with 0.1% formic acid aqueous solution(A)-acetonitrile(B) as mobile phases at gradient elution. MS data were collected by electrospray ionization in positive ion mode. Forty-seven phenylethylchromones was identified from NaCl-treated suspension cell samples of A. sinensis using UPLC-Q-Exactive-MS, including 22 flindersia-type 2-(2-phenylethyl) chromones and their glycosides, 10 5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones and 15 mono-epoxy or diepoxy-5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones. Additionally, 25 phenylethylchromones were quantitated by UPLC-QQQ-MS/MS. Overall, the rapid and efficient qualitative and quantitative analysis of phenylethylchromones in NaCl-treated suspension cells of A. sinensis by two LC-MS techniques, provides an important reference for the yield of phenylethylchromones in Aquilariae Lignum Resinatum using in vitro culture and other biotechnologies.


Assuntos
Cromonas , Thymelaeaceae , Cloreto de Sódio , Cromatografia Líquida , Flavonoides , Espectrometria de Massas em Tandem
11.
Angew Chem Int Ed Engl ; 62(12): e202218468, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36633173

RESUMO

Fluoroarenes are abundant and readily available feedstocks. However, due to the high reduction potentials of mono-fluoroarenes, their photoreduction remains a continuing challenge, motivating the development of efficient activation modes to address this issue. This report presents the blue light-induced N-heterocyclic carbene (NHC)-catalyzed single electron reduction of mono-fluoroarenes for biaryl cross-couplings. We discovered that under blue light irradiation, NHC/tBuOK combination could construct powerful photoactive architectures to promote single electron transfer for Caryl -F bond reduction via forming highly reducing NHC radical anion. Notably, the strategy was also successful to reduce Caryl -O, Caryl -N, and Caryl -S bonds for biaryl cross-couplings.

12.
Angew Chem Int Ed Engl ; 62(43): e202310764, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37668107

RESUMO

Pnictogen bonding (PnB) has gained recognition as an appealing strategy for constructing novel architectures and unlocking new properties. Within the synthetic community, the development of a straightforward and much simpler protocol for cross-electrophile C-PIII coupling remains an ongoing challenge with organic halides. In this study, we present a simple strategy for photoinduced PnB-enabled cross-electrophile C-PIII couplings using readily available chlorophosphines and organic halides via merging single electron transfer (SET) and halogen atom transfer (XAT) processes. In this photomediated transformation, the PnB formed between chlorophosphines and alkyl amines facilitates the photogeneration of PIII radicals and α-aminoalkyl radicals through SET. Subsequently, the resulting α-aminoalkyl radicals activate C-X bonds via XAT, leading to the formation of carbon radicals. This methodology offers operational simplicity and compatibility with both aliphatic and aromatic chlorophosphines and organic halides.

13.
Angew Chem Int Ed Engl ; 62(31): e202305088, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37119088

RESUMO

Visible-light-induced photoreaction of carboranes is an effective approach to prepare carborane-containing compounds. While several methods involving boron-centered carboranyl radicals have been established, those for carbon-centered carboranyl radicals are underdeveloped, except for the UV-light-promoted photohomolysis. Herein, we describe a simple but effective approach to access carbon-centered carboranyl radicals by photoreduction of carborane phosphonium salts under blue light irradiation without using transition metals and photocatalysts. The utility of the method was demonstrated by successfully preparing a range of carborane-oxindole-pharmaceutical hybrids by radical cascade reactions. Computational and experimental studies suggest that the carbon-centered carboranyl radicals are generated by single-electron transfer of the photoactive charge-transfer complexes between the salts and the additive potassium acetate.

14.
Angew Chem Int Ed Engl ; 62(41): e202306307, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37340517

RESUMO

The direct arylation polycondensation (DArP) has become one of the most important methods to construct conjugated polymers (CPs). However, the homocoupling side-reactions of aryl halides and the low regioseletive reactivities of unfunctionalized aryls hinder the development of DArP. Here, an efficient Pd and Cu co-catalyzed DArP was developed via inert C-S bond cleavage of aryl thioethers, of which robustness was exemplified by over twenty conjugated polymers (CPs), including copolymers, homopolymers, and random polymers. The capture of oxidative addition intermediate together with experimental and theoretic results suggested the important role of palladium (Pd) and copper (Cu) co-catalysis with a bicyclic mechanism. The studies of NMR, molecular weights, trap densities, two-dimensional grazing-incidence wide-angle X-ray scattering (2D-GIWAXS), and the charge transport mobilities revealed that the homocoupling reactions were significantly suppressed with high regioselectivity of unfunctionalized aryls, suggesting this method is an excellent choice for synthesizing high performance CPs.

15.
Chemistry ; 28(35): e202200869, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35543280

RESUMO

Aryl sulfides are in great demands in drugs and materials sciences. To avoid using nucleophilic and noxious thiols, many efforts have been focused on exploring novel sulfide resources. Herein, a reductive Pd-catalyzed, Ni-mediated method to synthesize aryl sulfides via a sulfide transfer reaction is developed. The utility and scope of this reaction is exemplified by various aryl electrophiles and aryl sulfides. Mechanistic studies reveal two competing catalytic cycles of sulfide transfer and aryl transfer in this reaction, where the former one is favored over the later one because of the large energy barrier difference during the transmetalation. Moreover, two important chemicals are late-stage functionalized by this method, exhibiting the potential applications in drugs and materials science.


Assuntos
Compostos de Sulfidrila , Sulfetos , Catálise
16.
BMC Infect Dis ; 22(1): 663, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915398

RESUMO

BACKGROUND: China has experienced a continuous decreasing trend in the incidence of hepatitis A in recent years. Temporal trend analyses are helpful in exploring the reasons for the changing trend. Thus, this study aims to analyse the incidence trend of viral hepatitis A by region and age group in mainland China from 2004 to 2017 to evaluate the effectiveness of prevention and control measures. METHODS: Data on hepatitis A and population information were collected and analysed with a joinpoint regression model. Annual percentage changes (APCs) and average annual percentage changes (AAPCs) were estimated for the whole country and for each region and age group. RESULTS: From 2004 to 2017, the seasonality and periodicity of hepatitis A case numbers were obvious before 2008 but gradually diminished from 2008 to 2011 and disappeared from 2012-2017. The national incidence of hepatitis A (AAPC = - 12.1%) and the incidence rates for regions and age groups showed decreasing trends, with differences in the joinpoints and segments. Regarding regions, the hepatitis A incidence in the western region was always the highest among all regions, while a nonsignificant rebound was observed in the northeastern region from 2011 to 2017 (APC = 14.2%). Regarding age groups, the hepatitis A incidence showed the fastest decrease among children (AAPC = - 15.3%) and the slowest decrease among elderly individuals (AAPC = - 6.6%). Among all segments, the hepatitis A incidence among children had the largest APC value in 2007-2017, at - 20.4%. CONCLUSION: The national annual incidence of hepatitis A continually declined from 2004 to 2017 and the gaps in hepatitis A incidence rates across different regions and age groups were greatly narrowed. Comprehensive hepatitis A prevention and control strategies, including the use of routine vaccination during childhood in mainland China, especially the implementation of the national Expanded Program on Immunization (EPI) in 2008, resulted in substantial progress from 2004 to 2017. However, gaps remain. Regular monitoring and analysis of hepatitis A epidemic data and prompt adjustment of hepatitis A prevention and control strategies focusing on children, elderly individuals and those living in certain regions are recommended.


Assuntos
Hepatite A , Polipose Adenomatosa do Colo , Idoso , Criança , China/epidemiologia , Hepatite A/epidemiologia , Humanos , Programas de Imunização , Incidência , Análise de Regressão
17.
Acta Pharmacol Sin ; 43(6): 1581-1593, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34462561

RESUMO

Helichrysetin (HEL), a chalcone isolated from Alpinia katsumadai Hayata, has an antitumor activity in human lung and cervical cancers. However, the inhibitory effect and underlying mechanism of HEL in gastric cancer have not been elucidated. Here, HEL significantly inhibited the growth of gastric cancer MGC803 cells in vitro and in vivo. HEL decreased expression and transcriptional regulatory activity of c-Myc and mRNA expression of c-Myc target genes. HEL enhanced mitochondrial oxidative phosphorylation (OXPHOS) and reduced glycolysis as evidenced by increased mitochondrial adenosine triphosphate (ATP) production and excessive reactive oxygen species (ROS) accumulation, and decreased the pPDHA1/PDHA1 ratio and Glyco-ATP production. Pyruvate enhanced OXPHOS after HEL treatment. c-Myc overexpression abolished HEL-induced inhibition of cell viability, glycolysis, and protein expression of PDHK1 and LDHA. PDHK1 overexpression also counteracted inhibitory effect of HEL on cell viability. Conversely, c-Myc siRNA decreased cell viability, glycolysis, and PDHK1 expression. NAC rescued the decrease in viability of HEL-treated cells. Additionally, HEL inhibited the overactivated mTOR/p70S6K pathway in vitro and in vivo. HEL-induced cell viability inhibition was counteracted by an mTOR agonist. mTOR inhibitor also decreased cell viability. Similar results were obtained in SGC7901 cells. HEL repressed lactate production and efflux in MGC803 cells. These results revealed that HEL inhibits gastric cancer growth by targeting mTOR/p70S6K/c-Myc/PDHK1-mediated energy metabolism reprogramming in cancer cells. Therefore, HEL may be a potential agent for gastric cancer treatment by modulating cancer energy metabolism reprogramming.


Assuntos
Proteínas Quinases S6 Ribossômicas 70-kDa , Neoplasias Gástricas , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Chalcona/análogos & derivados , Metabolismo Energético , Glicólise , Humanos , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
18.
Zhongguo Zhong Yao Za Zhi ; 47(18): 4996-5007, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164910

RESUMO

This study aims to investigate mechanism of "Ephedrae Herba-Descurainiae Semen Lepidii Semen" combination(MT) in the treatment of bronchial asthma based on network pharmacology and in vivo experiment, which is expected to lay a theoretical basis for clinical application of the combination. First, the potential targets of MT in the treatment of bronchial asthma were predicted based on network pharmacology, and the "Chinese medicine-active component-target-pathway-disease" network was constructed, followed by Gene Oncology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the potential targets. Molecular docking was used to determine the binding activity of key candidate active components to hub genes. Ovalbumin(OVA, intraperitoneal injection for sensitization and nebulization for excitation) was used to induce bronchial asthma in rats. Rats were classified into control group(CON), model group(M), dexamethasone group(DEX, 0.075 mg·kg~(-1)), and MT(1∶1.5) group. Hematoxylin and eosin(HE), Masson, and periodic acid-Schiff(PAS) staining were performed to observe the effect of MT on pathological changes of lungs and trachea and goblet cell proliferation in asthma rats. The levels of transforming growth factor(TGF)-ß1, interleukin(IL)6, and IL10 in rat serum were detected by enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein levels of mitogen-activated protein kinase 8(MAPK8), cyclin D1(CCND1), IL6, epidermal growth factor receptor(EGFR), phosphatidylinositol 3-kinase(PI3 K), and protein kinase B(Akt) by qRT-PCR and Western blot. Network pharmacology predicted that MAPK8, CCND1, IL6, and EGFR were the potential targets of MT in the treatment of asthma, which may be related to PI3 K/Akt signaling pathway. Quercetin and ß-sitosterol in MT acted on a lot of targets related to asthma, and molecular docking results showed that quercetin and ß-sitosterol had strong binding activity to MAPK, PI3 K, and Akt. In vivo experiment showed that MT could effectively alleviate the symptoms of OVA-induced asthma rats, improve the pathological changes of lung tissue, reduce the production of goblet cells, inhibit the inflammatory response of asthma rats, suppress the expression of MAPK8, CCND1, IL6, and EGFR, and regulate the PI3 K/Akt signaling pathway. Therefore, MT may relieve the symptoms and inhibit inflammation of asthma rats by regulating the PI3 K/Akt signaling pathway, and quercetin and ß-sitosterol are the candidate active components.


Assuntos
Asma , Medicamentos de Ervas Chinesas/uso terapêutico , Animais , Asma/tratamento farmacológico , Ciclina D1 , Dexametasona/efeitos adversos , Combinação de Medicamentos , Amarelo de Eosina-(YS)/efeitos adversos , Ephedra , Receptores ErbB , Hematoxilina/uso terapêutico , Interleucina-10 , Interleucina-6 , Proteína Quinase 8 Ativada por Mitógeno/uso terapêutico , Simulação de Acoplamento Molecular , Farmacologia em Rede , Ovalbumina/efeitos adversos , Ácido Periódico/efeitos adversos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quercetina , RNA Mensageiro , Ratos
19.
J Med Syst ; 45(4): 42, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608811

RESUMO

In confronting the sudden epidemic of COVID-19, China and other countries have been under great deal of pressure to block virus transmission and reduce death cases. Fangcang shelter hospital, which is converted from large-scale public venue, is proposed and proven to be an effective way for administering medical care and social isolation. This paper presents the practice in information technology support for a Fangcang shelter hospital in Wuhan, China. The experiences include the deployment strategy of IT infrastructure, the redesign of function modules in the hospital information system (HIS), equipment maintenance and medical staff training. The deployment strategy and HIS modules have ensured smoothness and efficiency of clinical work. The team established a quick response mechanism and adhered to the principle of nosocomial infection control. Deployment of network and modification of HIS was finished in the 48 hours before patient admittance. A repair hotline and remote support for equipment and software were available whenever medical workers met with any questions. No engineer ever entered the contaminated areas and no one was infected by the coronavirus during the hospital operation. Up to now, Fangcang shelter hospital is adopted by many regions around the world facing the collapse of their medical systems. This valuable experience in informatization construction and service in Wuhan may help participators involving in Fangcang shelter hospital get better information technology support, and find more practical interventions to fight the epidemic.


Assuntos
COVID-19/terapia , Abrigo de Emergência/organização & administração , Hospitais Especializados/organização & administração , Unidades Móveis de Saúde/organização & administração , Isolamento de Pacientes/estatística & dados numéricos , COVID-19/epidemiologia , China , Emergências , Arquitetura de Instituições de Saúde , Hospitais de Isolamento , Humanos , Tecnologia da Informação , Fatores de Risco
20.
Zhonghua Nan Ke Xue ; 27(7): 626-629, 2021 Jul.
Artigo em Zh | MEDLINE | ID: mdl-34914230

RESUMO

OBJECTIVE: To investigate the efficiency and complications of modified urethral reconstruction with lingual mucosa in the treatment of complicated anterior urethral stricture (CAUS). OBJECTIVE: To investigate the sexual experience and feelings of male patients with bladder cancer after transurethral resection of bladder tumor (TURBT), and provide some evidence for doctors and nurses in giving advice about the sexual problems of the patients. METHODS: This study included 32 male patients with bladder cancer after treated by TURBT from March 2020 to March 2021. The patients were aged 33-63 (51.91 ± 6.75) years, with a disease course of 13-38 (20.56 ± 7.49) month, and the interviews lasting 31-63 (39.06 ± 8.04) minutes. Among them, 10 (31.25%) lived in the rural area, 22 (68.75%) lived in the urban area, 12 (37.5%) had college education or above, 7 (21.88%) had senior high school education, 10 (31.25%) had junior high school education, and 3 (9.37%) had primary school education. Using the semi-structured method, we conducted interviews with the patients about their sexual experience and needs for sexual function rehabilitation and subjected the results of interviews to Colaizzi analysis. RESULTS: The interviews with the patients covered five topics, which showed intentional refraining from sexual life in 6 (18.75%) of the cases, worrying about hurting the partner by sexual contact in 8 (25%), neglecting sexual troubles in 8 (25%), negative emotions in 5 (15.63%), and expecting medical support in 17 (53.13%). CONCLUSIONS: Male patients with bladder cancer have poor sexual experience after TURBT. Doctors and nurses should inform the patients of potential sexual troubles during the treatment and follow-up, and provide relevant active intervention.


Assuntos
Procedimentos de Cirurgia Plástica , Neoplasias da Bexiga Urinária , Cistectomia , Progressão da Doença , Humanos , Masculino , Pesquisa Qualitativa , Neoplasias da Bexiga Urinária/cirurgia
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