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1.
JACS Au ; 4(2): 441-453, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38425924

RESUMO

A small chemical modification of the nucleobase structure can significantly enhance the photoactivity of DNA, which may incur DNA damage, thus holding promising applications in photochemotherapy treatment of cancers or pathogens. However, single substitution confers only limited phototoxicity to DNA. Herein, we combine femtosecond and nanosecond time-resolved spectroscopy with high-level ab initio calculations to disentangle the excited-state dynamics of 6-methylthioguanine (me6-TG) under variable wavelength UVA excitation (310-330 nm). We find that double substitution of nucleobases (thionation and methylation) boosts the photoactivity by introducing more reactive channels. Intriguingly, 1nNπ*, rather than 1nSπ*, acts as the doorway state engendering the formation of the long-lived reactive triplet state in me6-TG. The 1nNπ* induces a low spin-orbit coupling of 8.3 cm-1, which increases the intersystem crossing (ISC) time (2.91 ± 0.14 ns). Despite the slowed ISC, the triplet quantum yield (ΦT) still accounts for a large fraction (0.6 ± 0.1), consistent with the potential energy surface that favors excited-state bifurcation to 1nNπ*min (3.36 ± 0.15 ps) rather than 1ππ*min (5.05 ± 0.26 ps), such that the subsequent ISC to triplet via 1nNπ*min constitutes the main relaxation pathway in me6-TG. Although this ΦT is inferior to its single-substituted predecessor 6-thioguanine (6-TG, 0.8 ± 0.2), the effect of thionation in synergy with methylation opens a unique C-S bond cleavage pathway through crossing to a repulsive 1πσ* state, generating thiyl radicals as highly reactive intermediates that may invoke biological damage. This photodissociation channel is extremely difficult for conventional nucleobases. These findings demonstrate the synergistic effects of double functionality substitution in modulating excited-state dynamics and enhancing the photolabile character of DNA nucleobases, providing inspirations for the rational design of advanced photodynamic and photochemotherapy approaches.

2.
Cancer ; 130(S8): 1424-1434, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38217532

RESUMO

BACKGROUND: Immunohistochemistry (IHC) is an essential technique in surgical and clinical pathology for detecting diagnostic, prognostic, and predictive biomarkers for personalized cancer therapy. However, the lack of standardization and reference controls results in poor reproducibility, and a reliable tool for IHC quantification is urgently required. The objective of this study was to describe a novel approach in which H3F3B (histone H3, family 3B) can be used as an internal reference standard to quantify protein expression levels using IHC. METHODS: The authors enrolled 89 patients who had human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). They used a novel IHC-based assay to measure protein expression using H3F3B as the internal reference standard. H3F3B was uniformly expressed at the protein level in all tumor regions in cancer tissues. HER2 expression levels were measured with the H-score using HALO software. RESULTS: Kaplan-Meier analysis indicated that, among patients who had HER2-positive BC in The Cancer Genome Atlas data set and the authors' data set, the subgroup with low HER2 expression had a significantly better prognosis than the subgroup with high HER2 expression. Furthermore, the authors observed that HER2 expression levels were precisely evaluated using the proposed method, which can classify patients who are at higher risk of HER2-positive BC to receive trastuzumab-based adjuvant therapy. Dual-color IHC with H3F3B is an excellent tool for internal and external quality control of HER2 expression assays. CONCLUSIONS: The proposed IHC-based quantification method accurately assesses HER2 expression levels and provides insights for predicting clinical prognosis in patients with HER2-positive BC who receive trastuzumab-based adjuvant therapy.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Histonas , Imuno-Histoquímica , Reprodutibilidade dos Testes , Receptor ErbB-2/genética , Trastuzumab/uso terapêutico , Padrões de Referência , Biomarcadores Tumorais/metabolismo
3.
Ann Hematol ; 102(7): 1739-1744, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37160793

RESUMO

Acute leukemia (AL) is a malignancy from hematologic stem cells (HSC). Consolidation with intensive chemotherapy is required after induced remission and repeatedly causes treatment-related bleeding that is usually attributed to chemotherapy-induced thrombocytopenia (CIT). However, our previous study demonstrated that severe deficiency of plasma coagulation factor XIII (pFXIII) also participated in the bleeding of CIT in AL. However, the relationship between pFXIII deficiency and consolidation chemotherapy was unknown. Here, we observed the concentration of pFXIII in patients with AL before and after consolidation chemotherapy and reevaluated the correlation to bleeding in myelosuppression. Thus, we found that the concentration of pFXIII before chemotherapy in all patients was markedly lower than in the control data and was further decreased by chemotherapy, related to bleeding in myelosuppression. These findings indicated that chemotherapy-induced pFXIII deficiency should be of concern and explored in depth.


Assuntos
Antineoplásicos , Doenças da Medula Óssea , Deficiência do Fator XIII , Leucemia Mieloide Aguda , Humanos , Fator XIII , Quimioterapia de Consolidação , Hemorragia/tratamento farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Doença Aguda , Doenças da Medula Óssea/tratamento farmacológico , Antineoplásicos/uso terapêutico , Deficiência do Fator XIII/tratamento farmacológico
4.
Sci Rep ; 12(1): 20734, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456601

RESUMO

High tumor mutation load (TMB-H, or TMB ≥ 10) has been approved by the U.S. FDA as a biomarker for pembrolizumab treatment of solid tumors, including non­small cell lung cancer (NSCLC). Patients with cancer who have immunotherapy-resistant gene mutations cannot achieve clinical benefits even in TMB-H. In this study, we aimed to identify gene mutations associated with immunotherapy resistance and further informed mechanisms in NSCLC. A combined cohort of 350 immune checkpoint blockade-treated patients from Memorial Sloan Kettering Cancer Center (MSKCC) was used to identify genes whose mutations could negatively influence immunotherapy efficacy. An external NSCLC cohort for which profession-free survival (PFS) data were available was used for independent validation. CIBERSORT algorithms were used to characterize tumor immune infiltrating patterns. Immunogenomic features were analysed in the TCGA NSCLC cohort. We observed that PBRM1 mutations independently and negatively influence immunotherapy efficacy. Survival analysis showed that the overall survival (OS) and PFS of patients with PBRM1 mutations (MT) were significantly shorter than the wild type (WT). Moreover, compared with PBRM1-WT/TMB-H group, OS was worse in the PBRM1-MT/TMB-H group. Notably, in patients with TMB-H/PBRM1-MT, it was equal to that in the low-TMB group. The CIBERSORT algorithm further confirmed that the immune infiltration abundance of CD8+ T cells and activated CD4+ memory T was significantly lower in the MT group. Immunogenomic differences were observed in terms of immune signatures, T-cell receptor repertoire, and immune-related genes between WT and MT groups. Nevertheless, we noticed an inverse relationship, given that MT tumors had a higher TMB than the WT group in MSKCC and TCGA cohort. In conclusion, our study revealed that NSCLC with PBRM1 mutation might be an immunologically cold phenotype and exhibited immunotherapy resistance. NSCLC with PBRM1 mutation might be misclassified as immunoresponsive based on TMB.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Fenótipo , Imunoterapia , Mutação , Fatores Imunológicos , Proteínas de Ligação a DNA , Fatores de Transcrição/genética
5.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35409217

RESUMO

Plants evolve a prompt and robust immune system to defend themselves against pathogen infections. Pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) is the first battle layer activated upon the PAMP's perception, which leads to multiple defense responses. The plasma membrane (PM) H+-ATPases are the primary ion pumps to create and maintain the cellular membrane potential that is critical for various essential biological processes, including plant growth, development, and defense. This study discovered that the PM H+-ATPase AHA5 is negatively involved in Arabidopsis PTI against the virulent pathogen Pseudomonas syringae pvr. tomato (Pto) DC3000 infection. The aha5 mutant plants caused the reduced stomata opening upon the Pto infection, which was associated with the salicylic acid (SA) pathway. In addition, the aha5 mutant plants caused the increased levels of callose deposition, defense-related gene expression, and SA accumulation. Our results also indicate that the PM H+-ATPase activity of AHA5 probably mediates the coupling of H2O2 generation and the apoplast alkalization in PTI responses. Moreover, AHA5 was found to interact with a vital defense regulator, RPM1-interacting protein 4 (RIN4), in vitro and in vivo, which might also be critical for its function in PTI. In summary, our studies show that AHA5 functions as a novel and critical component that is negatively involved in PTI by coordinating different defense responses during the Arabidopsis-Pto DC3000 interaction.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Doenças das Plantas/genética , Imunidade Vegetal , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Pseudomonas syringae , Ácido Salicílico/metabolismo
6.
J Phys Chem B ; 126(1): 14-22, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34951313

RESUMO

The nucleobase analog 6-thioguanine (6-TG) has emerged as important immunosuppressant, anti-inflammatory, and anticancer drug in the past few decades, but its unique photosensitivity of absorbing strongly ultraviolet UVA light elicits photochemical hazards in many ways. The particularly intriguing yet unresolved question is whether the direct photoreaction of 6-TG can promote DNA-protein cross-links (DPCs) formation, which are large DNA adducts blocking DNA replication and physically impede DNA-related processes. Herein, by real-time observation of radical intermediates using time-resolved UV-vis absorption spectroscopy in conjunction with product analysis by HPLC-MS, we discover that UVA excitation of 6-TG triggers direct covalent cross-linking with tryptophan (TrpH) via an exquisite radical mechanism of electron transfer. The photoexcitation prepares the redox-active triplet 36-TG*, which initiates electron transfer with TrpH, creating TrpH•+ and 6-TG•- in the first step. The deprotonated Trp• undergoes radical-recombination with its geminate partner 6-TG•- and eliminates a H2S, leading to the cross-linking product 6-TG-Trp. The photoadduct structures (two chiral isomers and one constitutional isomer) are identified unambiguously, validating further the mechanism. These findings pinpoint the exact amino acid that is vulnerable to photo-cross-linking with 6-TG and establish a mechanistic framework for understanding mutagenic DPCs formation and developing photoprobes based on this new type of photo-cross-linking.


Assuntos
Tioguanina , Triptofano , DNA , Transporte de Elétrons , Elétrons
7.
Artigo em Chinês | MEDLINE | ID: mdl-34105461

RESUMO

OBJECTIVE: To investigate the relationship between average interval time of chemotherapy and prognosis in patients with acute leukemia (AL) during intensive treatment. METHODS: Data of 92 newly treated adult AL patients who received chemotherapy in The First Hospital of Lanzhou University from January 2010 to June 2019 were analyzed retrospectively. The patients were divided into groups according to the average interval time of chemotherapy during intensive treatment, and its influence on prognosis was analyzed. RESULTS: The median interval of chemotherapy during intensive therapy was 38 (20-64) days. According to the average interval of chemotherapy, patients were divided into 4 groups, including < 30 days group, 30-39 days group, 40-49 days group and ≥ 50 days group. The 3-year overall survival (OS) rate of the four groups was (84.9±8.0)%, (73.5±8.7)%, (56.5±11.1)% and (41.8±13.6)%, respectively (P=0.008). The 3-year progression-free survival (PFS) rate of the four groups was (63.6±11.1)%, (52.8±10.2)%, (38.2±10.8)% and (14.0±9.0)%, respectively (P=0.001). After comparison between the 4 groups, it was found that OS and PFS in ≥ 50 days group were significantly shorter than those in < 30 days group (P<0.008). Multivariate analysis showed that risk stratification and average chemotherapy interval ≥ 50 days were the common adverse factors affecting OS and PFS. CONCLUSION: The average chemotherapy interval ≥ 50 days during intensive therapy is an independent risk factor affecting the prognosis and survival of patients with AL. When the bone marrow is completely relieved and the peripheral hemogram recovers to an acceptable level, the consolidation therapy should be started as soon as possible. The interval < 30 days can significantly improve the prognosis compared with the interval ≥ 50 days.


Assuntos
Leucemia Mieloide Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Intervalo Livre de Doença , Humanos , Quimioterapia de Indução , Prognóstico , Estudos Retrospectivos
8.
Ther Clin Risk Manag ; 17: 405-414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017174

RESUMO

OBJECTIVE: To investigate macular vascular changes and underlying influencing factors using optical coherence tomography angiography (OCTA) after phacoemulsification in patients with cataracts. METHODS: Patients diagnosed with cataracts at the First Affiliated Hospital of Anhui Medical University from March to September 2019 were included. The macular retinal thickness, the microvascular density in the foveal, parafoveal, and perifoveal area, and the area of the foveal avascular zone (FAZ) were measured using OCTA at baseline, 1-week, 1-month, and 3-month post-operation. RESULTS: Forty-seven cataract patients (58 eyes) were eligible for this study. Compared with baseline thickness, the foveal, parafoveal, and perifoveal thicknesses, particularly in the inner retina, significantly increased at 1- and 3-month post-operation (P<0.05). There was a nonsignificant difference in the microvascular density of the foveal and perifoveal areas at 1-week, 1-month, and 3-month post-operation (P>0.05). At 1-month post-operation, the deep vessel density at the perifovea significantly increased (P<0.05). The FAZ area significantly diminished at 1- and 3-month post-operation compared with the baseline data (P<0.05). CONCLUSION: Phacoemulsification offers a satisfactory efficacy response, with an increased macular thickness, reduced FAZ area, and nonsignificant changes in the microvascular density at the perifovea after surgery.

9.
Int J Med Sci ; 18(3): 785-791, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33437214

RESUMO

Background: The molecular mechanism in the progression of ovarian clear cell carcinoma (OCCC) remains unclear. Objective: This study aimed to investigate the potential function of RAYLY in OCCC. Methods: To validate RAYLY expression, immunohistochemistry, quantitative real-time PCR and western blotting were performed in OCCC tissues and the cell lines of OCCC and epithelial ovarian carcinoma (EOC). Subsequently, the biological effects of RALYL were evaluated through colony formation, and cell proliferation, migration and invasion assays. Finally, RNA-sequencing and gene set enrichment analysis (GSEA) were conducted to explore potential mechanism of RALYL in OCCC. Results: In our study, RALYL was significantly down-regulated in a majority of OCCC tissues compared to adjacent non-tumorous tissues, and OCCC cells had a lower expression level of RALYL than that of EOC cells. OCCC patients with high RALYL expression had a better pathological stage and prognosis. In vitro, over-expression of RALYL inhibited cell proliferation, migration and invasion in OCCC. GSEA analysis and western blot indicated an enrichment of MAPK and CDH1 signaling pathways in OCCC cells without RALYL over-expression. Conclusions: RALYL played an important role in the progression of OCCC, and might serve as a potential prognostic biomarker and novel therapeutic target for OCCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Epitelial do Ovário/genética , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/metabolismo , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Caderinas/metabolismo , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/cirurgia , Linhagem Celular Tumoral , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Estadiamento de Neoplasias , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Ovariectomia , Ovário/patologia , Ovário/cirurgia , Prognóstico , Proteínas de Ligação a RNA/genética , RNA-Seq
10.
Plant Dis ; 105(1): 108-113, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33175655

RESUMO

Bacterial spot caused by Xanthomonas spp. is one of the major diseases in tomato. Xanthomonas perforans is the main pathogen of bacterial spot on tomato in Florida. Currently, application of copper fungicides is the primary measure used to manage this disease. However, the development of copper resistance in X. perforans and accumulation of copper in the environment are major concerns for excessive use of copper-based products in agriculture. Due to its antibacterial properties and low environmental impact, N-acetylcysteine (NAC), a small molecule commonly used in medicine for human bacterial diseases, has been studied in agriculture for the control of plant bacterial pathogens, including X. citri and Xylella fastidiosa. This study evaluated the effect of NAC alone and in combination with copper on a copper-resistant X. perforans strain in vitro and its ability to control bacterial spot of tomato under greenhouse and field conditions. In vitro, the minimum inhibitory concentration of NAC against the X. perforans strain was 2,048 mg liter-1. NAC increased sensitivity of the copper-resistant X. perforans to copper in vitro when application of NAC was followed by copper application after 6 h. In greenhouse assays, NAC applied alone or in combination with copper significantly (P < 0.05) reduced the disease severity of bacterial spot on tomato compared with the untreated control. NAC at 100 mg liter-1 + copper at 300 mg liter-1 consistently exhibited synergistic effects against bacterial spot. In the field trials, NAC at 1,000 mg liter-1 + copper at 150 mg liter-1 significantly reduced disease severity compared with the untreated control. Results from this study demonstrated that NAC significantly reduced the disease severity of bacterial spot of tomato and enhanced the efficacy of copper against copper-resistant X. perforans, indicating that NAC could be applied for the effective management of bacterial spot of tomato.


Assuntos
Solanum lycopersicum , Xanthomonas , Acetilcisteína/farmacologia , Cobre/farmacologia , Florida , Doenças das Plantas , Xylella
11.
Int J Mol Sci ; 21(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059380

RESUMO

Oxathiapiprolin was developed as a specific plant pathogenic oomycete inhibitor, previously shown to have highly curative and protective activities against the pepper Phytophthora blight disease under field and greenhouse tests. Therefore, it was hypothesized that oxathiapiprolin might potentially activate the plant disease resistance against pathogen infections. This study investigated the potential and related mechanism of oxathiapiprolin to activate the plant disease resistance using the bacterium Pseudomonas syringae pv tomato (Pst) and plant Arabidopsis interaction as the targeted system. Our results showed that oxathiapiprolin could activate the plant disease resistance against Pst DC3000, a non-target pathogen of oxathiapiprolin, in Arabidopsis, tobacco, and tomato plants. Our results also showed the enhanced callose deposition and H2O2 accumulation in the oxathiapiprolin-treated Arabidopsis under the induction of flg22 as the pathogen-associated molecular pattern (PAMP) treatment. Furthermore, increased levels of free salicylic acid (SA) and jasmonic acid (JA) were detected in the oxathiapiprolin-treated Arabidopsis plants compared to the mock-treated ones under the challenge of Pst DC3000. Besides, the gene expression results confirmed that at 24 h after the infiltration with Pst DC3000, the oxathiapiprolin-treated Arabidopsis plants had upregulated expression levels of the respiratory burst oxidase homolog D (RBOHD), JA-responsive gene (PDF1.2), and SA-responsive genes (PR1, PR2, and PR5) compared to the control. Taken together, oxathiapiprolin is identified as a novel chemical inducer which activates the plant disease resistance against Pst DC3000 by enhancing the callose deposition, H2O2 accumulation, and hormone SA and JA production.


Assuntos
Resistência à Doença/efeitos dos fármacos , Resistência à Doença/fisiologia , Hidrocarbonetos Fluorados/farmacologia , Doenças das Plantas/imunologia , Imunidade Vegetal/efeitos dos fármacos , Pirazóis/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucanos , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Polímeros/metabolismo , Pseudomonas syringae/patogenicidade , Ácido Salicílico/metabolismo , Nicotiana/efeitos dos fármacos , Nicotiana/genética , Nicotiana/metabolismo
12.
Chem Sci ; 11(31): 8204-8213, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34123091

RESUMO

We report here porphodilactol derivatives and their corresponding metal complexes. These systems show promise as "all-in-one" phototheranostics and are predicated on a design strategy that involves controlling the relationship between intersystem crossing (ISC) and photothermal conversion efficiency following photoexcitation. The requisite balance was achieved by tuning the aromaticity of these porphyrinoid derivatives and forming complexes with one of two lanthanide cations, namely Gd3+ and Lu3+. The net result led to a metalloporphodilactol system, Gd-trans-2, with seemingly optimal ISC efficiency, photothermal conversion efficiency and fluorescence properties, as well as good chemical stability. Encapsulation of Gd-trans-2 within mesoporous silica nanoparticles (MSN) allowed its evaluation for tumour diagnosis and therapy. It was found to be effective as an "all-in-one" phototheranostic that allowed for NIR fluorescence/photoacoustic dual-modal imaging while providing an excellent combined PTT/PDT therapeutic efficacy in vitro and in vivo in 4T1-tumour-bearing mice.

13.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438521

RESUMO

Many studies have shown that Orthosiphon stamineus extract (OE) has antioxidant activity, and we previously reported that OE protects the intestine against injury from a high-fat diet. However, the molecular mechanism underlying this protective effect of OE was unclear. Here, OE was separated according to polarity and molecular weight, and the antioxidant activity of each component was compared. The components with the highest antioxidant activity were analyzed by HPLC, which confirmed that rosmarinic acid (RA) was the main effective constituent in OE. OE and RA were then tested in a mouse high-fat diet-induced intestinal injury model. The antioxidant indices and morphological characteristics of the mouse jejunum were measured, and activation of the nuclear factor E2-related factor 2 (Nrf2) pathway and apoptosis of jejunal epithelial cells were analyzed. Of all the constituents in OE, RA contributed the most. Both RA and OE activated the Nrf2 pathway and increased downstream antioxidant enzyme activity. RA and OE protected the mouse intestine against high-fat diet-induced oxidative stress by preventing intestinal epithelial cell apoptosis via both extracellular and intracellular pathways. Thus, RA, the main effective constituent in OE, inhibits intestinal epithelial apoptosis by regulating the Nrf2 pathway in mice.


Assuntos
Cinamatos/farmacologia , Depsídeos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Orthosiphon/química , Animais , Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Intestinos/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ácido Rosmarínico
14.
J Phys Chem Lett ; 10(9): 2143-2150, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30995046

RESUMO

Human telomeric RNA (TERRA) containing thousands of G-rich repeats has the propensity to form parallel-stranded G-quadruplexes. The emerging crucial roles of TERRA G-quadruplexes in RNA biology fuel increasing attention for studying anticancer ligand binding with such structures, which, however, remains scarce. Here we utilized multiple steady-state and time-resolved spectroscopy analyses in conjunction with NMR methods and investigated thoroughly the binding behavior of TMPyP4 to a TERRA G-quadruplex dimer formed by the 10-nucleotide sequence r(GGGUUAGGGU). It is clearly identified that TMPyP4 intercalates into the 5'-5' stacking interface of two G-quadruplex blocks with a binding stoichiometry of 1:1 and binding constant of 1.92 × 106 M-1. This is consistent with the unique TERRA structural features of the enlarged π-π stacking plane of the A·(G·G·G·G)·A hexad at 5'-ends of each G-quadruplex block. The preferential binding of π-ligand porphyrin to the 5'-5' stacking interface of the native TERRA G-quadruplex dimer is first ascertained by the combination of dynamics and structural characterization.


Assuntos
Quadruplex G , Substâncias Intercalantes/química , Porfirinas/química , RNA/química , Telômero/química , Sequência de Bases , Dimerização , Humanos , Cinética , Ligantes , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
15.
Mol Plant ; 11(12): 1482-1491, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30342096

RESUMO

The Asteraceae (Compositae), a large plant family of approximately 24 000-35 000 species, accounts for ∼10% of all angiosperm species and contributes a lot to plant diversity. The most representative members of the Asteraceae are the economically important chrysanthemums (Chrysanthemum L.) that diversified through reticulate evolution. Biodiversity is typically created by multiple evolutionary mechanisms such as whole-genome duplication (WGD) or polyploidization and locally repetitive genome expansion. However, the lack of genomic data from chrysanthemum species has prevented an in-depth analysis of the evolutionary mechanisms involved in their diversification. Here, we used Oxford Nanopore long-read technology to sequence the diploid Chrysanthemum nankingense genome, which represents one of the progenitor genomes of domesticated chrysanthemums. Our analysis revealed that the evolution of the C. nankingense genome was driven by bursts of repetitive element expansion and WGD events including a recent WGD that distinguishes chrysanthemum from sunflower, which diverged from chrysanthemum approximately 38.8 million years ago. Variations of ornamental and medicinal traits in chrysanthemums are linked to the expansion of candidate gene families by duplication events including paralogous gene duplication. Collectively, our study of the assembled reference genome offers new knowledge and resources to dissect the history and pattern of evolution and diversification of chrysanthemum plants, and also to accelerate their breeding and improvement.


Assuntos
Chrysanthemum/genética , Evolução Molecular , Flores/genética , Genoma de Planta/genética , Biodiversidade , Cruzamento , Chrysanthemum/crescimento & desenvolvimento , Chrysanthemum/metabolismo , Flavonoides/biossíntese , Duplicação Gênica , Anotação de Sequência Molecular , Fenótipo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Retroelementos/genética , Sequências Repetidas Terminais/genética
16.
Oncol Lett ; 14(3): 2691-2698, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28928812

RESUMO

Ampelopsin (AMP) is an active ingredient of flavonoid compounds that is extracted from Ampelopsis megalophylla Diels et Gilg. The present study aimed at investigating the antitumor activities of AMP and the possible underlying molecular mechanisms in HeLa cells. A total of three types of tumor cell were selected to screen antitumor activities for AMP using the MTT assay. Flow cytometry was used to analyze the cell apoptotic proportion and the cell cycle. Rhodamine 123 staining was used to determine changes in mitochondrial transmembrane potential. Western blot analysis was used to determine the expression of apoptosis-associated proteins. The results of the present study demonstrated that AMP may inhibit the viability of HeLa cells in a dose- and time-dependent manner. Changes in morphology were observed using fluorescence microscopy. In addition, Annexin V-fluorescein isothiocyanate/propidium iodide (PI) double staining revealed that AMP induced apoptosis in a concentration-dependent manner and PI staining indicated that HeLa cells were arrested in S phase. Furthermore, western blot analysis demonstrated that AMP treatment induced apoptosis through activation of caspases 9 and 3, which was validated by the increasing ratio of B-cell lymphoma 2 (Bcl-2)-associated X protein to Bcl-2. Additionally, the loss of mitochondrial transmembrane potential and the release of cytochrome c suggested that AMP-induced apoptosis was associated with the mitochondrial pathway. Taken together, these results indicate that AMP may induce apoptosis via the mitochondrial signaling pathway in HeLa cells.

17.
Clin Neurol Neurosurg ; 158: 20-26, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28433725

RESUMO

BACKGROUND AND OBJECTIVES: Paraganglioma rarely develops in the spine. With few cases reported, little knowledge about this disease was known. The objective of this study is to illustrate the clinical features, imaging manifestations, pathological appearances and long-term outcomes of the consecutive surgeries by literature review. METHODS: The clinical and follow-up data of 18 patients who were diagnosed of spinal paraganglioma and treated with surgeries in our hospitals from 2003 to 2014 were retrospectively analyzed. RESULT: A total of fourteen patients radiographed of intra-spinal tumor underwent extra-capsular tumor resection. Of five patients with obvious vertebral bone damage, four cases underwent piecemeal resection, and the left one with sacral tumor underwent en bloc tumor excision. Spinal reconstruction was performed in all cases. Follow-up lasted for 16-96 months (44.1 months on average). There was no local recurrence or distant metastasis in cases without obvious bone invasion. Of those five cases with vertebral bone damage, one case suffered and survived from the repeat relapse of T1 vertebral body tumor. Local recurrence was not observed in one case with T10 vertebral tumor after tumor resection, but the tumor metastasized to T2 attachment during the follow-up and was finally eradicated by re-operation. No tumor recurrence was observed in the left three cases. CONCLUSION: Paraganglioma, usually benign, rarely occurs. Surgical resection, especially complete surgical resection, is preferred to treat spinal paraganglioma. Chemotherapy, radiotherapy, use of octreotide and other somatostatin are selected as adjuvant therapies, but their effects remain unknown.


Assuntos
Recidiva Local de Neoplasia/cirurgia , Procedimentos Ortopédicos/métodos , Paraganglioma/cirurgia , Compressão da Medula Espinal/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Paraganglioma/complicações , Paraganglioma/patologia , Estudos Retrospectivos , Compressão da Medula Espinal/etiologia , Fusão Vertebral/métodos , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/patologia , Resultado do Tratamento
18.
Taiwan J Obstet Gynecol ; 56(1): 46-50, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28254225

RESUMO

OBJECTIVE: Abdominal adhesions are primarily severe postoperative complications that can cause gynecological problems such as infertility and chronic pelvic pain. Inflammatory mediators are significantly related to adhesion formation, and hydrogen sulfide plays a significant anti-inflammatory role in multiple physiological processes. Therefore, the effect of NaHS, a hydrogen sulfide donor, on postoperative adhesion formation was examined in a rat uterine horn model. MATERIALS AND METHODS: A rat uterine horn model was created to evaluate whether NaHS, a hydrogen sulfide donor, could decrease postoperative adhesion formation. Rats were randomly grouped and administrated with different doses of NaHS, where DL-propargylglycine and low-molecular-weight heparin acted as negative and positive controls, respectively. The extent and severity of adhesions were assessed on the 14th postoperative day. Serum of rats was sampled for the determination of 27 cytokines using a chip. RESULTS: The severity and total scores of adhesion in rats given 112µM/kg and 56µM/kg NaHS were significantly less compared with those of the control group (p<0.01). Scores for the extent of adhesion re-formation in the DL-propargylglycine and control groups did not differ (p>0.05). At least six cytokines were involved in the procedures for the prevention of adhesion formation, as they varied significantly among different groups. CONCLUSION: Administration of NaHS could apparently reduce postoperative adhesion in the rat uterine horn model. This preventive effect may be associated with the variation of cytokine that is related to inflammatory.


Assuntos
Anti-Inflamatórios/uso terapêutico , Sulfeto de Hidrogênio/uso terapêutico , Complicações Pós-Operatórias/prevenção & controle , Útero/cirurgia , Animais , Feminino , Humanos , Modelos Animais , Distribuição Aleatória , Ratos , Ratos Wistar , Aderências Teciduais/prevenção & controle
19.
Medicine (Baltimore) ; 96(10): e6183, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272207

RESUMO

Dumbbell tumors can not only cause the compression of cervical cord and nerve root, but also invade the important structures and the surrounding organs, causing great harm to the patient. Toyama classification that is commonly used has not been evaluated and still requires independent validation.The objectives of this study were to evaluate and analyze the interobserver reliability and intraobserver reproducibility of Toyama classification system, explore the differences, discover the shortages, and evaluate the clinical value for diagnosis.One hundred sixty-five consecutive patients of a cervical dumbbell tumor with complete clinical and radiologic data were enrolled. Six surgeons determined the classification according to Toyama system. The classification was repeated 12 weeks later. Correlation coefficient (ICC) and kappa coefficient (κ) test were used to determine interobserver reliability and intraobserver reproducibility.The interobserver reliability for Toyama classification was moderate with a value of 0.432. The interobserver reproducibility for Toyama classification was moderate with a value of 0.608.The Toyama classification has landmark value in clinical practice, but it is a relatively cumbersome system. This study shows that it has low reliability and reproducibility. Accordingly, surgical management of the resection of dumbbell cervical tumors raises several problems, including preservation of the cervical nerve root, control of the vertebral artery, and maintenance of spine. There is a need to optimize the classification in the future.


Assuntos
Vértebras Cervicais/patologia , Neoplasias da Coluna Vertebral/classificação , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Neoplasias da Coluna Vertebral/patologia
20.
Mol Med Rep ; 15(4): 2083-2089, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259907

RESUMO

O-GlcNAcylation is a dynamic and reversible post-translational modification associated with the regulation of multiple cellular functions. The addition and removal of O­Linked ß-N-acetylglucosamine (O­GlcNAc) on target proteins is catalyzed by O­GlcNAc transferase (OGT) and O­GlcNAcase (OGA), respectively. Accumulating evidence suggests that O-GlcNAcylation is associated with the malignancy of several types of human cancer. To investigate the effect of O-GlcNAcylation on ovarian cancer phenotypes, global O­GlcNAc levels were decreased by OGT silencing through RNA interference and increased by inhibiting OGA activity with Thiamet­G. Transwell assay results demonstrated that OGT silencing inhibited the migration and invasion of SKOV3 and 59M ovarian cells in vitro, while Thiamet­G treatment promoted migration and invasion. Furthermore, a pull­down assay and western blot analysis demonstrated that Thiamet-G treatment enhanced RhoA activity and the phosphorylation of the Rho­associated protein kinase (ROCK) substrate, myosin light chain (MLC), while OGT silencing attenuated RhoA activity and MLC phosphorylation. In addition, RhoA silencing via RNA interference and inhibition of ROCK activity with Y­27632 prevented Thiamet­G­induced increases in cell migration and invasion. These data suggest that O­GlcNAcylation augments the motility of ovarian cancer cells via the RhoA/ROCK/MLC signaling pathway. Therefore, O­GlcNAcylation may be a potential target for the diagnosis and treatment of ovarian cancer.


Assuntos
Acetilglucosamina/metabolismo , Cadeias Leves de Miosina/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Ovário/patologia , Transdução de Sinais , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , N-Acetilglucosaminiltransferases/metabolismo , Invasividade Neoplásica/patologia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo
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