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1.
Fitoterapia ; 173: 105793, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158161

RESUMO

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3-6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2H)-one core with an α,ß-unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 µg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 µg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities.


Assuntos
Gastrodia , Policetídeos , Estrutura Molecular , Phoma , Acetilcolinesterase , Dicroísmo Circular
2.
Org Lett ; 25(10): 1711-1716, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36892283

RESUMO

Herein, we described a highly regio- and enantioselective Friedel-Crafts alkylation of aniline derivatives with in situ generated ortho-quinone methides enabled by chiral phosphoric acid, furnishing a wide range of enantioenriched triarylmethanes bearing three similar benzene rings in high yields (up to 98%) with excellent stereoselectivities (up to 98% ee). Furthermore, the large-scale reactions and diversified transformations of product demonstrate the practicality of the protocol. Density functional theory calculations elucidate the origin of the enantioselectivity.

3.
Org Biomol Chem ; 19(39): 8607-8612, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34569587

RESUMO

The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of ß-keto propargylamines via chiral phosphoric acid-catalyzed asymmetric Mannich reaction between ß-keto acids and C-alkynyl N-Boc N,O-acetals as easily available C-alkynyl imine precursors has been demonstrated here, affording a broad scope of ß-keto N-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97 : 3 er).

4.
J Nat Prod ; 83(11): 3471-3475, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180498

RESUMO

Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.


Assuntos
Cumarínicos/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Linhagem Celular Tumoral , Dicroísmo Circular , Cumarínicos/química , Cristalografia por Raios X , Humanos , Estrutura Molecular , Sesquiterpenos/química
5.
Med Sci Monit ; 26: e926669, 2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32948737

RESUMO

BACKGROUND The aim of this study was to analyze the risk factors of pressure injury (PI) in critically ill patients with cancer to build a risk prediction model for PI. MATERIAL AND METHODS Between January 2018 and December 2019, a total of 486 critically ill patients with cancer were enrolled in the study. Univariate analysis and binary logistic regression analysis were used to explore risk factors. Then, a risk prediction equation was constructed and a receiver operator characteristic (ROC) curve analysis model was used for prediction. RESULTS Of the 486 critically ill patients with cancer, 15 patients developed PI. Risk factors found to have a significant impact on PI in critically ill patients with cancer included the APACHE II score (P<0.001), semi-reclining position (P=0.006), humid environment/moist skin (P<0.001), and edema (P<0.001). These 4 independent risk factors were used in the regression equation, and the risk prediction equation was constructed as Z=0.112×APACHE II score +2.549×semi-reclining position +2.757×moist skin +1.795×edema-9.086. From the ROC curve analysis, the area under the curve (AUC) was 0.938, sensitivity was 100.00%, specificity was 83.40%, and Youden index was 0.834. CONCLUSIONS The PI risk prediction model developed in this study has a high predictive value and provides a basis for PI prevention and treatment measures for critically ill patients with cancer.


Assuntos
Modelos Biológicos , Neoplasias/epidemiologia , Úlcera por Pressão/epidemiologia , Idoso , China/epidemiologia , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
7.
Curr Comput Aided Drug Des ; 16(3): 222-230, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30706826

RESUMO

BACKGROUND: B-RafV600E kinase was identified as an important target in current cancer treatment, and the type II B inhibitors show good qualities in preclinical studies. Therefore, it is very important to discover novel II B inhibitors of B-RafV600E kinase. METHODS: In order to discover novel II B inhibitors of B-RafV600E kinase, virtual screening against ZINC database was performed by using a combination of pharmacophore modelling, molecular docking, 3DQSAR model and binding free energy (ΔGbind) calculation studies. The inhibitory activities against A375 cell lines of the hit compounds were tested by using MTT assay. RESULTS: Five promising hit compounds were obtained after screening, and all the five hit compounds showed good inhibitory rates against A375 cell lines. CONCLUSION: The combined approach of the virtual screening in our work is effective, which can be used to discover novel inhibitors with a new skeleton. In addition, the five compounds obtained from the screening showed good inhibitory rates against A375 cell lines, which can be considered to develop new II B inhibitors of B-RafV600E kinase.


Assuntos
Descoberta de Drogas , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Relação Quantitativa Estrutura-Atividade , Termodinâmica
8.
Onco Targets Ther ; 11: 7635-7642, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464512

RESUMO

BACKGROUND: (PD-L2), a ligand of programmed cell death protein 1 (PD-1), is an inhibitory receptor of T cells and activated B cells. Many studies have focused on PD-L1, another ligand of PD-1, and the prognostic significance of PD-L1 has been reported in many tumors. However, the expression of PD-L2 in relation to clinical outcomes has not been fully investigated in cancer patients. PATIENTS AND METHODS: In this study, we investigated the expression of PD-L2 via immunohistochemistry (IHC) in the pathological specimens of 348 patients treated for colorectal cancer (CRC). RESULTS: Strong PD-L2 expression was found in the cancer tissues from 41% of the CRC patients who also had a high TNM stage and carcinoembryonic antigen (CEA) concentration. We also carried out functional studies in vitro, which showed that PD-L2 did not influence the growth of the CRC cell line HCT116, but increased cell invasion. CONCLUSION: Collectively, these findings suggest that PD-L2 may be a potential therapeutic target for CRC.

9.
Oncotarget ; 7(19): 27458-67, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27050275

RESUMO

PURPOSE: To examine the function of serum lactic dehydrogenase (SLDH) level after intensity-modulated radiotherapy (IMRT) as a predictive factor for and loco-regional relapse free survival (LRFS), distant metastasis-free survival (DMFS), disease free survival (DFS), and overall survival(OS) among patients with in-situ nasopharyngeal carcinoma (NPC). RESULTS: Compared with the normal pt-SLDH group, elevated pt-SLDH demonstrated significant lower DMFS (46 versus 66 months, hazard ratio (HR) 4.07, 95% CI 2.43-6.80, p < 0.001), DFS (46 versus 63 months, HR 2.78, 95% CI 1.70-4.53, p < 0.001), and OS (54 versus 66 months, HR 2.93, 95% CI 1.65-5.23, p < 0.001). Distant metastasis were observed in 32.8% (20/61) patients with elevated pt-SLDH, and 8% (54/678) in normal SLDH (odds ratio (OR) 6.13, 95% CI 3.35-11.18, p < 0.001). COX regression showed that pt-SLDH was an independent prognostic factors for OS (HR 2.91, 95% CI 1.57-5.41, p < 0.001), DMFS (HR 4.21, 95% CI 2.51-7.07, p < 0.001), LRFS (HR 2.53, 95% CI 1.22-5.24, p < 0.001), and DFS (HR 2.81, 95% CI 1.72-4.59, p < 0.001). MATERIALS AND METHODS: The records of 739 in-situ NPC patients admitted to Zhejiang Cancer Hospital between January 2007 and May 2012 were retrospectively reviewed. The relationships between post-treatment SLDH (pt-SLDH) and LRFS, DMFS, DFS, and OS were analyzed. CONCLUSIONS: Our finding indicated that elevated pt-SLDH could be a simple available prognostic indicator for distant metastasis and survival for in-situ NPC patients.


Assuntos
Carcinoma/enzimologia , Carcinoma/radioterapia , L-Lactato Desidrogenase/sangue , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma/mortalidade , Carcinoma/patologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Metástase Neoplásica , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
10.
Org Lett ; 16(11): 3044-7, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24811051

RESUMO

The catalytic enantioselective conjugate addition of acetaldehyde to polyconjugated substrates, nitrodienynes and nitroenynes, has been accomplished using organocatalysis. Various functionalized 1,3-enynes and propargylic compounds were obtained in moderate to good yields with high enantioselectivity. The synthetic utilities of the conjugate addition reactions have been highlighted in the concise total synthesis of (+)-α-lycorane and the metal-free synthesis of chiral ß-alkynyl acids.


Assuntos
Acetaldeído/química , Alcinos/química , Alcinos/síntese química , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/síntese química , Nitrocompostos/química , Catálise , Estrutura Molecular , Estereoisomerismo
11.
PLoS One ; 9(3): e91357, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24667308

RESUMO

The microRNA319 (miR319) family is conserved among diverse plant species. In rice (Oryza sativa L.), the miR319 gene family is comprised of two members, Osa-miR319a and Osa-miR319b. We found that overexpressing Osa-miR319b in rice resulted in wider leaf blades and delayed development. Here, we focused on the biological function and potential molecular mechanism of the Osa-miR319b gene in response to cold stress in rice. The expression of Osa-miR319b was down-regulated by cold stress, and the overexpression of Osa-miR319b led to an enhanced tolerance to cold stress, as evidenced by higher survival rates and proline content. Also, the expression of a handful of cold stress responsive genes, such as DREB1A/B/C, DREB2A, TPP1/2, was increased in Osa-miR319b transgenic lines. Furthermore, we demonstrated the nuclear localization of the transcription factors, OsPCF6 and OsTCP21, which may be Osa-miR319b-targeted genes. We also showed that OsPCF6 and OsTCP21 expression was largely induced by cold stress, and the degree of induction was obviously repressed in plants overexpressing Osa-miR319b. As expected, the down-regulation of OsPCF6 and OsTCP21 resulted in enhanced tolerance to cold stress, partially by modifying active oxygen scavenging. Taken together, our findings suggest that Osa-miR319b plays an important role in plant response to cold stress, maybe by targeting OsPCF6 and OsTCP21.


Assuntos
Adaptação Fisiológica/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , MicroRNAs/genética , Oryza/genética , Folhas de Planta/crescimento & desenvolvimento , Estresse Fisiológico/genética , Temperatura Baixa , Perfilação da Expressão Gênica , Oryza/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
13.
J Org Chem ; 77(8): 4103-10, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22443260

RESUMO

A new class of chiral primary amine catalysts bearing multiple hydrogen-bonding donors have been designed and synthesized. The newly developed bifunctional organocatalysts efficiently catalyzed not only enantioselective conjugate addition of aromatic ketones to nitroolefins in good yields (up to 87%) with excellent enantioselectivities (97→99% ee) but also enantioselective conjugate addition of acetone to nitroolefins in excellent yields (90-96%) with high enantioselectivities (up to 97% ee).


Assuntos
Acetona/química , Alcenos/química , Aminas/química , Cetonas/química , Catálise , Ligação de Hidrogênio , Estrutura Molecular , Estereoisomerismo
14.
Org Lett ; 13(23): 6200-3, 2011 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-22044048

RESUMO

Biologically important and synthetically challenging spirocyclopentaneoxindoles with four contiguous stereocenters including one spiroquaternary stereocenter have been constructed in good yields (72-87%) with excellent diastereoselectivity (16:1→30:1 dr) and enantioselectivity (93→99% ee) by a combined Ru-catalyzed cross-metathesis/organocatalyzed asymmetric double-Michael addition sequence.


Assuntos
Ciclopentanos/síntese química , Indóis/síntese química , Rutênio/química , Compostos de Espiro/síntese química , Catálise , Técnicas de Química Combinatória , Ciclopentanos/química , Indóis/química , Estrutura Molecular , Oxindóis , Compostos de Espiro/química , Estereoisomerismo
15.
Org Lett ; 13(23): 6160-3, 2011 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-22050288

RESUMO

A highly diastereo- and enantioselective organocatalytic protocol for the synthesis of biologically important spirocyclopentaneoxindoles containing the oxime functional group from easily accessible 3-allyl-substituted oxindoles and nitroolefins has been developed by a one-pot Michael addition/ISOC/fragmentation sequence.


Assuntos
Ciclopentanos/síntese química , Indóis/síntese química , Oximas/química , Compostos de Espiro/síntese química , Catálise , Ciclização , Ciclopentanos/química , Indóis/química , Estrutura Molecular , Oxindóis , Compostos de Espiro/química , Estereoisomerismo
16.
Chem Asian J ; 6(1): 220-5, 2011 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-21077095

RESUMO

The first catalytic asymmetric conjugate addition of 1,3-dicarbonyl compounds to nitroenynes catalyzed by cinchona alkaloid-based thiourea organocatalysts has been developed. The 1,4-addition adducts were obtained solely, in moderate to good yields (up to 93%) with good enantioselectivities (up to 99% ee). This protocol affords a conceptually different entry to the precursors of pharmaceutically important chiral ß-alkynyl acid derivatives and synthetically useful chiral nitroalkynes. Notably, the protocol worked well with both aryl- and alkyl-substituted alkynyl substrates.


Assuntos
Alcenos/química , Malonatos/química , Tioureia/química , Catálise , Alcaloides de Cinchona/química , Estrutura Molecular , Estereoisomerismo
17.
Cell Immunol ; 236(1-2): 154-60, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16188246

RESUMO

CD28 is expressed abnormally on human multiple myeloma (MM) cells but the significance had not been identified until now. In this paper, we are suggesting that abnormal expression of CD28 might be a marker of tumour progression. We therefore took the approach of generating a hybridoma cell line capable of secreting agonist monoclonal antibody directed against human CD28 (agonist anti-CD28 mAb) and then determined the expression of CD28 molecules on the MM cell lines U266 and XG1. The biological effects of agonist anti-CD28 mAb on cell growth and proliferation of U266 and XG1 cell lines were then analysed. Our results showed that the expression of CD28 on U266 and XG1 was significantly higher than that of PBTC or Jurkat cells. We found that by adding the agonist anti-CD28 mAb to cultures of U266 and XG1 cells their rate of growth and proliferation was obviously inhibited. Further morphological and molecular analyses found that U266 and XG1 incubated with agonist anti-CD28 mAb showed signs of nuclear condensation, chromatin marginal changes, cells membrane breaking, and cytoplasmic shrinkage. Vacuoles and apoptotic bodies were also observed using a transmission electron microscope and the development of typical DNA laddering patterns were found by the use of electrophoresis assays, suggesting that U266 and XG1 cells were undergoing apoptosis induced by agonist anti-CD28 mAb in vitro.


Assuntos
Apoptose/imunologia , Antígenos CD28/imunologia , Mieloma Múltiplo/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/farmacologia , Antígenos CD28/metabolismo , Linhagem Celular Tumoral/fisiologia , Linhagem Celular Tumoral/ultraestrutura , Cromatografia de Afinidade , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão/métodos , Mieloma Múltiplo/metabolismo
18.
Cell Immunol ; 236(1-2): 146-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16165113

RESUMO

B7 family molecules are mainly expressed on the outer membrane of antigen-presenting cells. Here, our results demonstrate that CD80, CD86, and PD-L1 molecules are also expressed on T-cells that have been activated by simultaneous exposure to anti-CD3 and anti-CD28 mAbs, but PD-L2 and GL50 molecules were not detectable during the first six days of culture that follow such stimulation. We have analysed the time course of B7 family molecule expression on activated T-cells. CD28 and its ligands, CD80/CD86, have a high degree of co-localization and exhibit compartmental distribution on the membrane of activated T-cells, which is visualized by confocal microscopy. Interestingly, the co-localization of PD-1 and its ligand also exhibit similar phenomenon. Additionally, we provide evidence indicating that the CD80, CD86, and PD-L1 molecules are functional, since T-cells expressing B7 family molecules are able to stimulate the proliferation of highly purified allogeneic or autologous T-cells. Anti-CD80, anti-CD86, and soluble CD28-Ig protein could significantly attenuate the proliferation of T-cells, whereas anti-PD-L1 mAb may lead to the expansion of activated T-cells. We can conclude that activated T-cells expressing B7 family molecules could act as "APC" to trigger purified T-cells, and B7 family molecules play important roles during the activation of T-cells. These results indicate a need for further work, exploring the regulatory roles these molecules may play in immune responses.


Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Glicoproteínas de Membrana/metabolismo , Peptídeos/metabolismo , Linfócitos T/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD , Antígeno B7-H1 , Antígenos CD28/imunologia , Complexo CD3/imunologia , Células Cultivadas , Humanos , Citometria de Varredura a Laser/métodos , Leucócitos Mononucleares , Ativação Linfocitária/imunologia , Camundongos
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