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1.
J Org Chem ; 87(22): 15571-15581, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36322051

RESUMEN

We report here a regiospecific [3 + 2] annulation between aminocyclopropanes and various functionalized alkynes enabled by a P/N-heteroleptic Cu(I) photosensitizer under photoredox catalysis conditions. Thus, a divergent construction of 3-aminocyclopentene derivatives including methylsulfonyl-, arylsulfonyl-, chloro-, ester-, and trifluoromethyl-functionalized aminocyclopentenes could be achieved with advantages of high regioselectivity, broad substrate compatibility, and mild and environmentally benign reaction conditions.


Asunto(s)
Alquinos , Fármacos Fotosensibilizantes , Catálisis
2.
Molecules ; 27(23)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36500336

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease with limited therapeutic options. Pseudognaphalium affine (D. Don) Anderb. is a medicinal and edible plant used to treat cough, asthma, and COPD for a long time in folk medicine. The objective of this study is to evaluate the effect of Pseudognaphalium affine (D. Don) Anderb. extract (GAE) and investigate the possible underlying mechanism in vivo and in vitro. In vivo, the administration of GAE in a rat COPD model could significantly ameliorate lung damage and pulmonary function by inhibiting the production of pro-inflammatory cytokines. Western blot and real-time PCR results showed that GAE could suppress nuclear translocation of nuclear factor-kappa B (NF-κB), which indicated that GAE down-regulated the NF-κB pathway. Moreover, GAE protected against tumor necrosis factor (TNF)-α induced inflammatory response in BEAS-2B and inhibited the NF-κB pathway. All data suggested that GAE exhibited its anti-COPD effect by inhibiting pro-inflammatory cytokines, which may be associated with the inhibition of the NF-κB pathway.


Asunto(s)
Asteraceae , Enfermedad Pulmonar Obstructiva Crónica , Ratas , Animales , FN-kappa B/metabolismo , Transducción de Señal , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Pulmón , Factor de Necrosis Tumoral alfa/metabolismo , Citocinas/metabolismo , Asteraceae/metabolismo , Extractos Vegetales/uso terapéutico
3.
Bull Entomol Res ; 111(3): 270-281, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32993843

RESUMEN

Peristenus spretus (Hymenoptera: Braconidae) is one of the most important endoparasitoids used for biological control of the green mirid bug, Apolygus lucorum Meyer-Dür (Heteroptera: Miridae). However, what we know about its reproductive genetics is very limited. Here, the composition of ovarian proteins in P. spretus was analyzed. Mass spectrum data searched against the non-redundant NCBI protein and UniProt protein database identified 1382 proteins and revealed an enrichment of the heat shock protein 83 (HSP83) in P. spretus ovary. The Pshsp83 complete cDNA is 2175 bp in length and encodes a protein of 724 amino acids with a calculated molecular mass of 83.4 kDa and a theoretical isoelectric point of 4.87. Transcription of Pshsp83 appeared from days 1 to 13 post-emergence and peaked at 13th day. Immuno-localization showed that the HSP83 protein was present in cytoplasm of germarium and in egg chambers of the whole ovariole. The transcript abundance of Pshsp83 fluctuated drastically after heat shocks at different temperatures and the maximum emerged at 35°C. The exposure to 35°C caused no dramatic effects on reproductive parameters of adult females such as pupation rate, cocoon weight, emergence rate, sex ratio and developmental duration, but did on longevity. These results suggested that the HSP83 protein is involved in life-span regulation in the P. spretus.


Asunto(s)
Proteínas de Choque Térmico/metabolismo , Himenópteros/metabolismo , Ovario/metabolismo , Animales , Agentes de Control Biológico/metabolismo , ADN Complementario/genética , Femenino , Expresión Génica , Proteínas de Choque Térmico/genética , Respuesta al Choque Térmico , Himenópteros/genética , Himenópteros/fisiología , Longevidad , Espectrometría de Masas , Oviposición , Parásitos/genética , Parásitos/metabolismo , Parásitos/fisiología , Proteoma , Proteómica , Reproducción , Avispas/genética , Avispas/metabolismo , Avispas/fisiología
4.
Org Biomol Chem ; 18(19): 3707-3716, 2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32356531

RESUMEN

Mild [2 + 2] photodimerization of enone substrates was induced by donor-acceptor fluorophores. Enone substrates were activated efficiently for anti-head to head dimerizations with a high yield (up to 83%) and high selectivity. The adjustable excited state potential also allows donor-acceptor fluorophores to be used for isomerization of the above substrates, confirming the potential of donor-acceptor fluorophores as energy transfer photocatalysts.

5.
Appl Microbiol Biotechnol ; 104(5): 2017-2028, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31930453

RESUMEN

This paper focuses on the production of a high-affinity monoclonal antibody (mAb) that can efficiently detect and block purinergic ligand-gated ion channel 7 receptor (P2X7R). To achieve this goal, the extracellular domain of human P2X7R, P2X7R-ECD, was used as an immunogen for BALB/c mice, inducing them to produce spleen lymphocytes that were subsequently fused with myeloma cells. Screening of the resultant hybridoma clones resulted in the selection of one stable positive clone that produced a qualified mAb, named 4B3A4. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated that the purity of the purified 4B3A4 mAb was above 85%, with prominent bands corresponding to molecular weights of 55 kDa (heavy chain) and 25 kDa (light chain), and the BCA assay showed that the concentration of the purified 4B3A4 mAb was 0.3 mg/mL. Western blot analysis revealed that the 4B3A4 mAb could specifically recognize and bind both P2X7R-ECD and the full-length P2X7R protein. Laser scanning confocal microscopy (LSCM) revealed that the 4B3A4 mAb specifically bound to P2X7R on the membrane of human peripheral blood mononuclear cells (PBMCs). P2X7R expression was significantly different between healthy individuals and people with certain cancers as determined by flow cytometry (FCM). In addition, the 4B3A4 mAb significantly reduced ATP-stimulated Ca2+ entry and YO-PRO-1 uptake, which indicated that the 4B3A4 mAb effectively blocked P2X7R activity. These data indicate that the 4B3A4 mAb can be further used as not only an antibody to detect cell surface P2X7R but also as a therapeutic antibody to target P2X7R-related signaling pathways.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Receptores Purinérgicos P2X7/inmunología , Animales , Anticuerpos Monoclonales/química , Especificidad de Anticuerpos , Benzoxazoles/metabolismo , Calcio/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Femenino , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/inmunología , Leucocitos Mononucleares/metabolismo , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Dominios Proteicos , Compuestos de Quinolinio/metabolismo , Receptores Purinérgicos P2X7/química
6.
Angew Chem Int Ed Engl ; 57(42): 13897-13901, 2018 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30152915

RESUMEN

The first catalytic hydrocarboxylation of enamides and imines with CO2 to generate valuable α,α-disubstituted α-amino acids is reported. Notably, excellent chemo- and regio-selectivity are achieved, significantly different from previous reports on ß-carboxylation of enamides, homocoupling or reduction of imines. Moreover, this transition-metal-free procedure exhibits low loading of an inexpensive catalyst, easily available substrates, mild reaction conditions, high efficiency, facile scalability and easy product derivatization, providing great potential for application in organic synthesis, pharmaceutical chemistry, and biochemistry.

7.
Chemistry ; 23(15): 3631-3636, 2017 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-27981644

RESUMEN

A series of phenanthroline-based ligands have been synthesised and their influence as bidentate nitrogen ligands in heteroleptic [Cu(P^P)(N^N)]+ photosensitisers in light-driven water reduction has been studied. In this noble-metal-free Cu-Fe-based photocatalytic water reduction system, the structural effects of the nitrogen ligands have been explored, including the steric and electronic effects of substituents at the 2,9- and 4,7-positions of phenanthroline. Ligands were prepared that led to increased hydrogen generation, with turnover numbers (TONCu ) of up to 1388 being observed. All the new complexes were electrochemically and photophysically characterised. We demonstrate for the first time that the presence of fluorine in nitrogen ligands increases the efficacy of copper complexes in photocatalytic hydrogen production.

8.
J Am Chem Soc ; 138(27): 8588-94, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27322175

RESUMEN

Herein, we report a novel cobalt-catalyzed stereodivergent transfer hydrogenation of alkynes to Z- and E-alkenes. Effective selectivity control is achieved based on a rational catalyst design. Moreover, this mild system allows for the transfer hydrogenation of alkynes bearing a wide range of functional groups in good yields using catalyst loadings as low as 0.2 mol %. The general applicability of this procedure is highlighted by the synthesis of more than 50 alkenes with good chemo- and stereoselectivity. A preliminary mechanistic study revealed that E-alkene product was generated via sequential alkyne hydrogenation to give Z-alkene intermediate, followed by a Z to E alkene isomerization process.

9.
Chemistry ; 22(4): 1233-8, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26691442

RESUMEN

The reduction of water has been achieved through a non-noble-metal-based homogeneous catalyst system that is formed in situ. Optimisation of the ligand quantities increased catalyst turnover numbers compared to preformed complexes. Mechanistic studies confirm a heteroleptic Cu complex as the active photosensitiser (PS) and an in situ formed Fe-phosphido dimer complex as the water reduction catalyst. The in situ method has been used to screen a range of ligands for the active PS, which has led to the identification a number of structural features important to longevity and performance.

10.
J Econ Entomol ; 108(4): 1779-85, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26470319

RESUMEN

In China, Adelphocoris lineolatus (Goeze) (Hemiptera: Miridae) is an important pest of alfalfa, cotton, and other crops, while Peristenus spretus (Chen & van Achterberg) (Hymenoptera: Braconidae) is the dominant nymphal parasitoid of this mirid bug. In the present study, the toxicity of 17 common insecticides to A. lineolatus was evaluated, and the susceptibility of P. spretus to the insecticides with high toxicity to A. lineolatus was tested under laboratory conditions. Of the 17 insecticides tested, 12 (beta cypermethrin, deltamethrin, carbosulfan, acetamiprid, emamectin benzoate, imidacloprid, phoxim, chlorpyrifos, acephate, profenophos, hexaflumuron, and abamectin) had a highly toxic effect on second-instar nymphs of A. lineolatus, with LC(50) values ranging from 0.58 to 14.85 mg a.i. (active ingredient) liter(-1). Adults of P. spretus were most sensitive to chlorpyrifos, with LC(50) values of 0.03 mg a.i. liter(-1), followed by phoxim, acetamiprid, profenophos, carbosulfan, acephate, deltamethrin, emamectin benzoate, imidacloprid, beta-cypermethrin, and abamectin, with LC(50) values ranging from 0.06 to 3.09, whereas hexaflumuron exhibited the least toxicity to the parasitoid, with LC(50) values >500 mg a.i. liter(-1). A risk quotient analysis indicated that beta-cypermethrin, emamectin benzoate, abamectin, and hexaflumuron when applied against A. lineolatus were the least toxic to P. spretus.


Asunto(s)
Heterópteros , Control de Insectos , Insecticidas , Control Biológico de Vectores , Avispas/efectos de los fármacos , Animales , China , Heterópteros/crecimiento & desarrollo , Heterópteros/parasitología , Insecticidas/toxicidad , Dosificación Letal Mediana , Ninfa/parasitología , Avispas/fisiología
11.
Org Lett ; 26(18): 3945-3950, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38679885

RESUMEN

A Pd-catalyzed highly regio- and stereoselective hydrocyanation was developed, providing a novel approach to the stereodivergent synthesis of ß-cyano-substituted acrylates in good yields with a wide substrate scope. The judicious selection of ligands was crucial for elegant control over the stereodivergence. Furthermore, the success of the E-hydrocyanation hinges on the right matching of Pd and L1, which not only ensured the catalytic activity but also prevented the formation of α-cyanation products.

12.
Aging (Albany NY) ; 16(7): 6188-6211, 2024 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-38552216

RESUMEN

BACKGROUND: REEP4 is involved in the regulation of the biological process of mitosis. Lower grade glioma (LGG), as a malignant tumor, is accompanied by abnormalities in mitosis, but there have been no reports of REEP4 so far. METHODS: We collected transcriptome data, DNA methylation data and the clinical characteristics of thousands of patients with LGG. Various big data analysis methods and molecular biology experiments were employed to reveal the impact of REEP4 on the pathological process of LGG. RESULTS: It was found that the expression of REEP4 was significantly elevated and negatively regulated by its methylation site. Therefore, both the high expression of REEP4 and low methylation state of cg16311504 showed that the patients are correlated with lower patient survival rate. In addition, high REEP4 expression participates in the regulation of various cancer-related cellular signaling pathways, such as the cell cycle, MAPK signaling pathway, NOD-like receptor signaling pathway, etc. More importantly, the level of immune cell infiltration significantly increased in the high expression group of REEP4 in the LGG tumor microenvironment and REEP4 has a high positive correlation with PD-L1 and other immune checkpoints. CONCLUSIONS: In brief, this study is the first to introduce REEP4 in malignant tumors, which can be used as an independent risk factor that participates in the malignant process of LGG. More importantly, REEP4 has the potential to become a new star in the field of anti-tumor treatment.


Asunto(s)
Neoplasias Encefálicas , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Glioma , Humanos , Glioma/genética , Glioma/metabolismo , Glioma/patología , Glioma/mortalidad , Pronóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/mortalidad , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Microambiente Tumoral/genética , Clasificación del Tumor , Transcriptoma , Femenino
13.
Chin J Nat Med ; 22(1): 89-96, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38278562

RESUMEN

As the search for effective treatments for COVID-19 continues, the high mortality rate among critically ill patients in Intensive Care Units (ICU) presents a profound challenge. This study explores the potential benefits of traditional Chinese medicine (TCM) as a supplementary treatment for severe COVID-19. A total of 110 critically ill COVID-19 patients at the Intensive Care Unit (ICU) of Vulcan Hill Hospital between Feb., 2020, and April, 2020 (Wuhan, China) participated in this observational study. All patients received standard supportive care protocols, with a subset of 81 also receiving TCM as an adjunct treatment. Clinical characteristics during the treatment period and the clinical outcome of each patient were closely monitored and analysed. Our findings indicated that the TCM group exhibited a significantly lower mortality rate compared with the non-TCM group (16 of 81 vs 24 of 29; 0.3 vs 2.3 person/month). In the adjusted Cox proportional hazards models, TCM treatment was associated with improved survival odds (P < 0.001). Furthermore, the analysis also revealed that TCM treatment could partially mitigate inflammatory responses, as evidenced by the reduced levels of proinflammatory cytokines, and contribute to the recovery of multiple organic functions, thereby potentially increasing the survival rate of critically ill COVID-19 patients.


Asunto(s)
COVID-19 , Humanos , Medicina Tradicional China , SARS-CoV-2 , Enfermedad Crítica , Resultado del Tratamiento
14.
Chemistry ; 19(47): 15972-8, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-24123302

RESUMEN

A series of heteroleptic copper(I) complexes with bidentate PP and NN chelate ligands was prepared and successfully applied as photosensitizers in the light-driven production of hydrogen, by using [Fe3(CO)12] as a water-reduction catalyst (WRC). These systems efficiently reduces protons from water/THF/triethylamine mixtures, in which the amine serves as a sacrificial electron donor (SR). Turnover numbers (for H) up to 1330 were obtained with these fully noble-metal-free systems. The new complexes were electrochemically and photophysically characterized. They exhibited a correlation between the lifetimes of the MLCT excited state and their efficiency as photosensitizers in proton-reduction systems. Within these experiments, considerably long excited-state lifetimes of up to 54 µs were observed. Quenching studies with the SR, in the presence and absence of the WRC, showed that intramolecular deactivation was more efficient in the former case, thus suggesting the predominance of an oxidative quenching pathway.

15.
Angew Chem Int Ed Engl ; 52(1): 419-23, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23047871

RESUMEN

Of noble descent: a fully noble-metal-free system for the photocatalytic reduction of water at room temperature has been developed. This system consists of Cu(I) complexes as photosensitizers and [Fe(3)(CO)(12)] as the water-reduction catalyst. The novel Cu-based photosensitizers are relatively inexpensive, readily available from commercial sources, and stable to ambient conditions, thus making them an attractive alternative to the widely used noble-metal based systems.

16.
J Pain Res ; 16: 2155-2169, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397274

RESUMEN

Purpose: Recent studies have shown that acupuncture may have great potential in the treatment of Bell's palsy. However, the bibliometric analysis of this field has not been summarized properly. Thus, the purpose of this study is to analyze the hotspot of acupuncture for Bell's Palsy. Methods: The core collection database of Web of Science was searched for relevant publications from 2000 to 2023, and countries, institutions, authors, keywords, and literature were analyzed and visualized by bibliometric softwareCiteSpace 5.1.R6, Vosviewer, BICOMB, and gCLUTO to explore the scientific achievements, research collaboration networks, research hot spots, and research trends. Results: 229 publications were included in this study. The most cited journal is Journal of Otolaryngology-Head & Neck Surgery; the most prolific country is China; the most prolific author is Li Ying, moreover, the collaboration among scholars is poor; Kyung Hee University is the most prolific institution studying acupuncture for Bell's Palsy. Reference burst detection indicates that traditional Chinese Medicine philosophy, the role of acupuncture in the prognosis of facial palsy, mechanism of acupuncture to improve facial nerve function, and the use of electroacupuncture are starting to become new research hotspots. Conclusion: The field of acupuncture for Bell's Palsy has developed rapidly in recent years, and new research trends are mainly: combination with traditional Chinese medicine, the role of acupuncture in the prognosis of facial palsy, mechanism of acupuncture to improve facial nerve function, and the use of electroacupuncture. However, research in this field is still dominated by case reports and clinical trials, and there is a lack of large-scale, multicenter clinical trials and animal experiments there are still many problems in institutional cooperation and experimental design, which requires relevant researchers to strengthen cooperation and improve experimental design.

17.
BMC Med Genomics ; 15(1): 194, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36100894

RESUMEN

BACKGROUND: This study attempted to verify the potential of KCNJ14 as a biomarker in colorectal cancer (CRC). METHODS: Data on transcriptomics and DNA methylation and the clinical information of CRC patients were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. Biological information analysis methods were conducted to determine the role of KCNJ14 in the prognosis, diagnosis, immune cell infiltration, and regulation mechanism of CRC patients. The effect of KCNJ14 on the proliferation and migration of HCT116 and SW480 CRC cell lines was verified by in vitro experiments (MTT, colony-forming, wound healing, and transwell assays). Western blotting was performed to detect the effect of KCNJ14 on the levels of mTOR signalling pathway-related proteins. RESULTS: KCNJ14 expression was remarkably increased in CRC tissues and cell lines, which reduced the overall survival time of patients. KCNJ14 mRNA was negatively regulated by its methylation site cg17660703, which can also endanger the prognosis of patients with CRC. Functional enrichment analysis suggested that KCNJ14 is involved in the mTOR, NOD-like receptor, and VEGF signalling pathways. KCNJ14 expression was positively correlated with the number of CD4 + T cells and negatively correlated with that of CD8 + T cells in the immune microenvironment. KCNJ14 knockdown significantly reduced not only the proliferation and migration of CRC cell lines but also the levels of mTOR signalling pathway-related proteins. CONCLUSIONS: This study not only increases the molecular understanding of KCNJ14 but also provides a potentially valuable biological target for the treatment of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Canales de Potasio de Rectificación Interna/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Humanos , Serina-Treonina Quinasas TOR/metabolismo , Microambiente Tumoral
18.
Hortic Res ; 8(1): 94, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33931608

RESUMEN

Low temperature causes anther dysfunction, severe pollen sterility and, ultimately, major yield losses in crop plants. Previous studies have shown that the gibberellic acid (GA) metabolic pathway plays an important role in this process by regulating tapetum function and pollen development. However, the interaction mechanism of GA with other hormones mediating anther development is still unclear. Herein, we collected and analyzed almond (Amygdalus communis L.) anthers at the meiosis, tetrad, 1-nucleus, and mature 2-nucleus stages. The growth rate per 1000 anthers exhibited a significant positive correlation with the total bioactive GA compound content, and the levels of all bioactive GA compounds were highest in the 1-nucleus pollen stage. GA3 treatment experiments indicated that exogenous GA3 increased the levels of indole-3-acetic acid (IAA), trans-zeatin (tZ), and jasmonic acid (JA) and decreased the levels of salicylic acid (SA) and abscisic acid (ABA); moreover, GA3 improved pollen viability and quantities under cold conditions, whereas PP333 (paclobutrazol, an inhibitor of GA biosynthesis) was antagonistic with GA3 in controlling anther development. RNA-seq and qRT-PCR results showed that GA played an important role in anther development by regulating the expression of other phytohormone pathway genes, dehydration-responsive element-binding/C-repeat binding factor (DREB1/CBF)-mediated signaling genes, and anther development pathway genes. Our results reveal the novel finding that GA interacts with other hormones to balance anther development under normal- and low-temperature conditions in almond.

19.
Org Lett ; 23(11): 4478-4482, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-33988383

RESUMEN

An efficient, mild, and atom-economical synthesis of benzo[b]fluorenols from 1,6-enynes has been developed under photocatalytic conditions. A single P/N heteroleptic Cu(I)-photosensitizer might exhibit both energy-transfer and photoredox catalytic activities in the formation of benzo[b]fluorenols.

20.
J Org Chem ; 75(6): 1888-91, 2010 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-20178371

RESUMEN

The self-assembly behavior of ionic liquids with acyclic polyethers was studied. The cations of 1-alkyl-3-methylimidazolium salts and 1-alkylpyridinium salts could form complexes at a ratio of 1:1 with poly(ethylene glycol)-800 (PEG800) and poly(propylene glycol)-1000 (PPG1000) in which the chain length was suitable to wrap around the cations. On the basis of the investigation by NMR, mass spectrometry, UV-vis spectroscopy, and TG analysis, the formation and characteristics of the novel complexes were discussed.

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