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1.
Inorg Chem ; 63(28): 12929-12934, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38954498

RESUMO

An efficient method for the selective conversion of glycerol, the major byproduct of the biodiesel manufacturing process, to lactic acid in water via acceptorless dehydrogenation has been developed. In the presence of a water-soluble [Cp*Ir(6,6'-(OH)2-2,2'-bpy)(H2O)][OTf]2 (0.1 mol %) and KOH (1.1 equiv), the reaction proceeded at 120 °C for 24 h to afford the desired product in >99% yield with >99% selectivity. It was confirmed that OH functional groups in the ligand were crucial for the activity of the iridium complex. Furthermore, density functional theory calculations and mechanistic experiments were also undertaken.

2.
Dig Liver Dis ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38851974

RESUMO

PURPOSE: Relative dose intensity (RDI) is a measurement of chemotherapy (CT) dose defined as the actual dose received divided by the standard calculated dose during a set period. The study objective was to assess the impact of a RDI ≥ 80% on response and survival of patients treated in first line CT by FOLFOXIRI or FOLFIRINOX ± Bevacizumab (BV) for an unresectable metastatic colorectal cancer (mCRC). MATERIALS AND METHODS: It was a retrospective, non-interventional, multicenter study calculating RDI from the first cycles of CT to the first CT-scan evaluation (CT-scan1). Objective response and disease control rates (ORR and DCR), progression-free survival (PFS) and overall survival (OS) were compared between patients with RDI ≥ 80% and <80% and results were adjusted for age, gender, ECOG, tumor location, number of metastatic sites, RAS and BRAF status, the CT regimen, the use of BV, the delay from C1 to CT scan1. RESULTS: Among 152 screened patients, 100 met inclusion criteria, with a mean (± standard deviation) age at 59.0 (± 10.7) years. The ECOG performance status was 0-1 in 96 (96%) patients; metastases were synchronous in 95 (95%), RAS and BRAF were mutated in 60 (60%) and 22 (22%), respectively. ORR was observed in 51 (51%) at CT-scan1 with median PFS and OS of 10.5 and 21.9 months, respectively. A RDI ≥ 80% was observed in 44 (44%) patients without impact on ORR (ORa: 1.04, 95% CI: 0.37 to 2.89, p = 0.94) but was significantly associated to improved PFS and OS with HRa 0.50 (95%CI: 0.29 to 0.87, p = 0.013) and 0.52 (95% CI: 0.29 to 0.91, p = 0.023), respectively. CONCLUSION: Our results suggest a low level of FOLFOXIRI or FOLFIRINOX +/- BV exposure in first-line mCRC is associated with a significant trend on PFS and OS.

3.
Cell Death Dis ; 15(5): 338, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744809

RESUMO

Epitranscriptomic RNA modifications are crucial for the maintenance of glioma stem cells (GSCs), the most malignant cells in glioblastoma (GBM). 3-methylcytosine (m3C) is a new epitranscriptomic mark on RNAs and METTL8 represents an m3C writer that is dysregulated in cancer. Although METTL8 has an established function in mitochondrial tRNA (mt-tRNA) m3C modification, alternative splicing of METTL8 can also generate isoforms that localize to the nucleolus where they may regulate R-loop formation. The molecular basis for METTL8 dysregulation in GBM, and which METTL8 isoform(s) may influence GBM cell fate and malignancy remain elusive. Here, we investigated the role of METTL8 in regulating GBM stemness and tumorigenicity. In GSC, METTL8 is exclusively localized to the mitochondrial matrix where it installs m3C on mt-tRNAThr/Ser(UCN) for mitochondrial translation and respiration. High expression of METTL8 in GBM is attributed to histone variant H2AZ-mediated chromatin accessibility of HIF1α and portends inferior glioma patient outcome. METTL8 depletion impairs the ability of GSC to self-renew and differentiate, thus retarding tumor growth in an intracranial GBM xenograft model. Interestingly, METTL8 depletion decreases protein levels of HIF1α, which serves as a transcription factor for several receptor tyrosine kinase (RTK) genes, in GSC. Accordingly, METTL8 loss inactivates the RTK/Akt axis leading to heightened sensitivity to Akt inhibitor treatment. These mechanistic findings, along with the intimate link between METTL8 levels and the HIF1α/RTK/Akt axis in glioma patients, guided us to propose a HIF1α/Akt inhibitor combination which potently compromises GSC proliferation/self-renewal in vitro. Thus, METTL8 represents a new GBM dependency that is therapeutically targetable.


Assuntos
Glioblastoma , Subunidade alfa do Fator 1 Induzível por Hipóxia , Metiltransferases , Células-Tronco Neoplásicas , Proteínas Proto-Oncogênicas c-akt , Metilação de RNA , Animais , Humanos , Camundongos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Carcinogênese/genética , Carcinogênese/patologia , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Camundongos Nus , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA de Transferência/metabolismo , RNA de Transferência/genética , Transdução de Sinais , Metilação de RNA/genética , Receptores Proteína Tirosina Quinases/metabolismo
4.
Nucleic Acids Res ; 52(12): 7063-7080, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38808662

RESUMO

Cohesin plays a crucial role in the organization of topologically-associated domains (TADs), which influence gene expression and DNA replication timing. Whether epigenetic regulators may affect TADs via cohesin to mediate DNA replication remains elusive. Here, we discover that the histone demethylase PHF2 associates with RAD21, a core subunit of cohesin, to regulate DNA replication in mouse neural stem cells (NSC). PHF2 loss impairs DNA replication due to the activation of dormant replication origins in NSC. Notably, the PHF2/RAD21 co-bound genomic regions are characterized by CTCF enrichment and epigenomic features that resemble efficient, active replication origins, and can act as boundaries to separate adjacent domains. Accordingly, PHF2 loss weakens TADs and chromatin loops at the co-bound loci due to reduced RAD21 occupancy. The observed topological and DNA replication defects in PHF2 KO NSC support a cohesin-dependent mechanism. Furthermore, we demonstrate that the PHF2/RAD21 complex exerts little effect on gene regulation, and that PHF2's histone-demethylase activity is dispensable for normal DNA replication and proliferation of NSC. We propose that PHF2 may serve as a topological accessory to cohesin for cohesin localization to TADs and chromatin loops, where cohesin represses dormant replication origins directly or indirectly, to sustain DNA replication in NSC.


Assuntos
Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona , Coesinas , Replicação do DNA , Proteínas de Ligação a DNA , Células-Tronco Neurais , Animais , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Cromatina/metabolismo , Origem de Replicação , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Genoma/genética , Fator de Ligação a CCCTC/metabolismo , Fator de Ligação a CCCTC/genética , Camundongos Knockout
5.
Org Lett ; 26(9): 1857-1862, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38407095

RESUMO

A general method for the hydrogenation of quinones to hydroquinones under atmospheric pressure has been developed. In the presence of [Cp*Ir(2,2'-bpyO)(H2O)] (0.5-1 mol %), a range of products were obtained in high yields. Furthemore, the expansion of this catalytic system to the hydrogenation of 1,4-benzoquinone diimines was also presented. Functional groups in the bpy ligand were found to be crucial for the catalytic activity of iridium complexes.

6.
Cell Death Differ ; 30(8): 1973-1987, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37468549

RESUMO

MAD2 is a spindle assembly checkpoint protein that participates in the formation of mitotic checkpoint complex, which blocks mitotic progression. RNF8, an established DNA damage response protein, has been implicated in mitotic checkpoint regulation but its exact role remains poorly understood. Here, RNF8 proximity proteomics uncovered a role of RNF8-MAD2 in generating the mitotic checkpoint signal. Specifically, RNF8 competes with a small pool of p31comet for binding to the closed conformer of MAD2 via its RING domain, while CAMK2D serves as a molecular scaffold to concentrate the RNF8-MAD2 complex via transient/weak interactions between its p-Thr287 and RNF8's FHA domain. Accordingly, RNF8 overexpression impairs glioma stem cell (GSC) mitotic progression in a FHA- and RING-dependent manner. Importantly, low RNF8 expression correlates with inferior glioma outcome and RNF8 overexpression impedes GSC tumorigenicity. Last, we identify PLK1 inhibitor that mimics RNF8 overexpression using a chemical biology approach, and demonstrate a PLK1/HSP90 inhibitor combination that synergistically reduces GSC proliferation and stemness. Thus, our study has unveiled a previously unrecognized CAMK2D-RNF8-MAD2 complex in regulating mitotic checkpoint with relevance to gliomas, which is therapeutically targetable.


Assuntos
Proteínas de Ciclo Celular , Glioma , Proteínas Mad2 , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glioma/genética , Glioma/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Mitose , Proteínas Nucleares/metabolismo , Fuso Acromático/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
7.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1145-1175, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005800

RESUMO

There are 500 species of Viola(Violaceae) worldwide, among which 111 species are widely distributed in China and have a long medicinal history and wide varieties. According to the authors' statistics, a total of 410 compounds have been isolated and identified from plants of this genus, including flavonoids, terpenoids, phenylpropanoids, organic acids, nitrogenous compounds, sterols, saccharides and their derivatives, volatile oils and cyclotides. The medicinal materials from these plants boast anti-microbial, anti-viral, anti-oxidant and anti-tumor activities. This study systematically reviewed the chemical constituents and pharmacological activities of Viola plants to provide a basis for further research and clinical application.


Assuntos
Viola , Viola/química , Extratos Vegetais/farmacologia , Flavonoides , Terpenos/farmacologia , China
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-970587

RESUMO

There are 500 species of Viola(Violaceae) worldwide, among which 111 species are widely distributed in China and have a long medicinal history and wide varieties. According to the authors' statistics, a total of 410 compounds have been isolated and identified from plants of this genus, including flavonoids, terpenoids, phenylpropanoids, organic acids, nitrogenous compounds, sterols, saccharides and their derivatives, volatile oils and cyclotides. The medicinal materials from these plants boast anti-microbial, anti-viral, anti-oxidant and anti-tumor activities. This study systematically reviewed the chemical constituents and pharmacological activities of Viola plants to provide a basis for further research and clinical application.


Assuntos
Viola/química , Extratos Vegetais/farmacologia , Flavonoides , Terpenos/farmacologia , China
9.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2805-2812, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384617

RESUMO

Qilian Mountains, is an important ecological function area, an important ecological security barrier, the river runoff region in Northwest China, as well as a sensitive area to global climate change and fragile area of ecological environment. The ecological environment in this area played an important role in the economic development of Northwest China. Based on the observation data of temperature and precipitation in Qilian Mountains, MOD10A2 snow products and the flow data of Shiyang River, Heihe River and Shule River, we systematically analyzed the characteristics of climate change from 1961 to 2020, and the impacts of climate change on water resources under the scenario of climate warming. The results showed that, from 1961 to 2020, the annual average temperature increased significantly, with the rate reaching 0.39 ℃·(10 a)-1. The warming rate was the highest in the western part of Qilian Mountains, followed by the middle and eastern regions. The warming trend was the strongest in winter and the lowest in spring. The average temperature changed abruptly in 1997. The annual average precipitation increased with flucturation, with a rate of 10 mm·(10 a)-1, which increased most obviously in the middle of Qilian Mountains. After 2004, it entered a rainy period, with a warm and humid trend. The precipitation in the four seasons showed an increasing trend and the increase of precipitation in summer contributed the most to the annual precipitation. Annual precipitation was dominated by interannual scale change, and the contribution rate of 2.8-year was approximately 64.3%. The snow cover of Qilian Mountains was obviously affected by temperature and snowfall, which was negatively correlated with summer temperature and positively correlated with snowfall. From 2016 to 2020, the temperature increase had slowed down in Qilian Mountains, the snowfall had increased, and the snow cover tended to increase. After 2000, the temperature and precipitation increased more obviously, the meltwater from glacier and snow increased, the mountainous runoff of Shiyang River, Heihe River and Shule River had an increasing trend. Our findings are of great significance to the construction of ecological civilization and coping with climate change in Qilian Mountains.


Assuntos
Mudança Climática , Recursos Hídricos , Camada de Gelo , Chuva , Neve , China
10.
Bull Cancer ; 109(4): 457-464, 2022 Apr.
Artigo em Francês | MEDLINE | ID: mdl-35094840

RESUMO

INTRODUCTION: The Pronopall score, which distinguishes 3 prognostic groups in patients with advanced cancer, was initially proposed in 2008 and validated in a study published in 2018 but including patients between 2009 and 2010. Since the last decade, cancer management and therapeutic options have progressed. The objective of this study was to confirm the value of this score in patients with digestive and thoracic cancer. METHODS: From July 2019 to November 2020, this retrospective multi-center study included patients with digestive or thoracic cancers who fulfilled the same inclusion criteria as those used in the initial study, and in whom the Pronopall score could be calculated using its four variables (albumin serum level, LDH level, ECOG score, number of metastatic sites). Survival curves were analyzed using the Kaplan-Meier method. RESULTS: One hundred patients were included. According to the Pronopall score, patients were separated into group A (score 8-10, 7 patients), group B (score 4-7, 41 patients) and group C (score 0-3, 52 patients). Median overall survival was 73 days, CI [17-129], 228 days, CI [128-328] and 575 days, CI [432-718] for groups A, B and C, respectively. Survival at 2 months was 28 % for population A, 61 % for population B, and 94 % for population C. CONCLUSION: This study confirms that the Pronopall score still allows clinically relevant discrimination of patients, score C being associated with a good prognosis compared to scores A and B.


Assuntos
Neoplasias , Humanos , Prognóstico , Estudos Retrospectivos
11.
Cell Death Differ ; 29(7): 1379-1394, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35058574

RESUMO

The histone variant H2AZ is overexpressed in diverse cancer types where it facilitates the accessibility of transcriptional regulators to the promoters of cell cycle genes. However, the molecular basis for its dysregulation in cancer remains unknown. Here, we report that glioblastomas (GBM) and glioma stem cells (GSCs) preferentially overexpress H2AZ for their proliferation, stemness and tumorigenicity. Chromatin accessibility analysis of H2AZ2 depleted GSC revealed that E2F1 occupies the enhancer region within H2AZ2 gene promoter, thereby activating H2AZ2 transcription. Exploration of other H2AZ2 transcriptional activators using a customized "anti-H2AZ2" query signature for connectivity map analysis identified STAT3. Co-targeting E2F and STAT3 synergistically reduced the levels of H2AZ, histone 3 lysine 27 acetylation (H3K27ac) and cell cycle gene transcription, indicating that E2F1 and STAT3 synergize to activate H2AZ gene transcription in GSCs. Remarkably, an E2F/STAT3 inhibitor combination durably suppresses GSC tumorigenicity in an orthotopic GBM xenograft model. In glioma patients, high STAT3 signaling is associated with high E2F1 and H2AZ2 expression. Thus, GBM has uniquely opted the use of E2F1- and STAT3-containing "enhanceosomes" that integrate multiple signaling pathways to achieve H2AZ gene activation, supporting a translational path for the E2F/STAT3 inhibitor combination to be applied in GBM treatment.


Assuntos
Neoplasias Encefálicas , Fator de Transcrição E2F1 , Glioblastoma , Glioma , Histonas , Fator de Transcrição STAT3 , Acetilação , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/genética , Cromatina/metabolismo , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioma/genética , Glioma/metabolismo , Histonas/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
12.
Endosc Int Open ; 9(10): E1504-E1511, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34540542

RESUMO

Background and study aims Prognostic and risk factors for upper gastrointestinal bleeding (UGIB) might have changed overtime because of the increased use of direct oral anticoagulants and improved gastroenterological care. This study was undertaken to assess the outcomes of UGIB in light of these new determinants by establishing a new national, multicenter cohort 10 years after the first. Methods Consecutive outpatients and inpatients with UGIB symptoms consulting at 46 French general hospitals were prospectively included between November 2017 and October 2018. They were followed for at least for 6 weeks to assess 6-week rebleeding and mortality rates and factors associated with each event. Results Among the 2498 enrolled patients (mean age 68.5 [16.3] years, 67.1 % men), 74.5 % were outpatients and 21 % had cirrhosis. Median Charlson score was 2 (IQR 1-4) and Rockall score was 5 (IQR 3-6). Within 24 hours, 83.4 % of the patients underwent endoscopy. The main causes of bleeding were peptic ulcers (44.9 %) and portal hypertension (18.9 %). The early in-hospital rebleeding rate was 10.5 %. The 6-week mortality rate was 12.5 %. Predictors significantly associated with 6-week mortality were initial transfusion (OR 1.54; 95 %CI 1.04-2.28), Charlson score > 4 (OR 1.80; 95 %CI 1.31-2.48), Rockall score > 5 (OR 1.98; 95 %CI 1.39-2.80), being an inpatient (OR 2.45; 95 %CI 1.76-3.41) and rebleeding (OR 2.6; 95 %CI 1.85-3.64). Anticoagulant therapy was not associated with dreaded outcomes. Conclusions The 6-week mortality rate remained high after UGIB, especially for inpatients. Predictors of mortality underlined the weight of comorbidities on outcomes.

13.
Sci Adv ; 7(36): eabf6033, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34516894

RESUMO

Glioblastoma (GBM) is a uniformly lethal disease driven by glioma stem cells (GSCs). Here, we use a chemical biology approach to unveil previously unknown GBM dependencies. By studying sulconazole (SN) with anti-GSC properties, we find that SN disrupts biotin distribution to the carboxylases and histones. Transcriptomic and metabolomic analyses of SN-treated GSCs reveal metabolic alterations that are characteristic of biotin-deficient cells, including intracellular cholesterol depletion, impairment of oxidative phosphorylation, and energetic crisis. Furthermore, SN treatment reduces histone biotinylation, histone acetylation, and expression of superenhancer-associated GSC critical genes, which are also observed when biotin distribution is genetically disrupted by holocarboxylase synthetase (HLCS) depletion. HLCS silencing impaired GSC tumorigenicity in an orthotopic xenograft brain tumor model. In GBM, high HLCS expression robustly indicates a poor prognosis. Thus, the dependency of GBM on biotin distribution suggests that the rational cotargeting of biotin-dependent metabolism and epigenetic pathways may be explored for GSC eradication.

14.
Cells ; 10(6)2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205102

RESUMO

TGF-ß/Smad signalling has been the subject of extensive research due to its role in the cell cycle and carcinogenesis. Modifications to the TGF-ß/Smad signalling pathway have been found to produce disparate effects on neurogenesis. We review the current research on canonical and non-canonical TGF-ß/Smad signalling pathways and their functions in neurogenesis. We also examine the observed role of neurogenesis in neuropsychiatric disorders and the relationship between TGF-ß/Smad signalling and neurogenesis in response to stressors. Overlapping mechanisms of cell proliferation, neurogenesis, and the development of mood disorders in response to stressors suggest that TGF-ß/Smad signalling is an important regulator of stress response and is implicated in the behavioural outcomes of mood disorders.


Assuntos
Transtornos do Humor/metabolismo , Doenças do Sistema Nervoso/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Humanos
15.
Medicine (Baltimore) ; 100(16): e25373, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33879666

RESUMO

INTRODUCTION: Radiation induced gliomas often occurs after radiation therapy for other brain tumors. Medulloblastoma often occurs in children and its associated radiation-induced glioblastoma multiforme's (GBM) after radiotherapy often has a long latency period. Our case is very unique because the medulloblastoma was detected at an advance age and the latency period of radiation-induced GBM was relatively shorter. PATIENTS CONCERNS: A 64-year-old male was first admitted at our hospital in March 2018 with dizziness, vomiting, and blurred vision. DIAGNOSIS: Magnetic resonance imaging of brain revealed a lesion with local mixed density and mass enhancement in left cerebellar region. Histopathology established medulloblastoma (World Health Organization) grade 4 and a classic histological subtype after surgery. INTERVENTION: Surgical resection followed by radiation therapy were the initial therapeutic modalities. OUTCOMES: In April 2019, the patient was readmitted with dizziness and blurred vision. Magnetic resonance imaging showed the left cerebellar hemisphere bulky enhancement lesion. Again, a multimodal therapy comprising surgical resection, radiation therapy as well as chemotherapy was adapted after histopathology established GBM. LESION: Radiotherapy for medulloblastoma patients at advance ages is a critical predisposing factor for the development of radiation-induced GBM in a very short period of time. We suggest that, radiotherapy as adjuvant therapy for medulloblastoma patients at advance ages should be chosen with extreme caution.


Assuntos
Neoplasias Cerebelares/terapia , Glioblastoma/etiologia , Meduloblastoma/terapia , Neoplasias Induzidas por Radiação/etiologia , Radioterapia Adjuvante/efeitos adversos , Terapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade
16.
Curr Microbiol ; 77(4): 588-601, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30963199

RESUMO

Herbaspirillum sp. WT00C is a tea-plant-specific endophytic bacterium. A genomic survey revealed an intact pathway for selenocompound metabolism in the genome of this bacterium. When it was cultured with sodium selenate, Herbaspirillum sp. WT00C was able to turn the culture medium to red. Electron microscopy and energy-dispersive X-ray spectroscopy confirmed that Herbaspirillum sp. WT00C reduced selenite (Se6+) to elemental selenium (Se0), and selenium nanoparticles (SeNPs) were secreted outside bacterial cells and grew increasingly larger to form Se-nanospheres and finally crystallized to form selenoflowers. Biochemical assays showed that selenospheres contained proteins but not carbohydrates or lipids. The improvement of selenium enrichment of tea plants by Herbaspirillum sp. WT00C was also tested. After Herbaspirillum sp. WT00C was inoculated into tea seedlings via needle injection and soaking tea-cutting methods, this endophytic bacterium markedly enhanced selenium enrichment of tea. When the tea seedlings inoculated by soaking tea-cutting mode were cultivated in the selenium-containing soils, selenium contents of tea leaves in three experimental groups were more than twofold compared to those of control groups. Our study demonstrates that the endophytic bacterium Herbaspirillum sp. WT00C has the ability to reduce selenate and improve selenium enrichment of tea.


Assuntos
Camellia sinensis/química , Camellia sinensis/microbiologia , Herbaspirillum/metabolismo , Ácido Selênico/metabolismo , Selênio/metabolismo , Solo/química , Endófitos/metabolismo , Herbaspirillum/genética , Oxirredução , Filogenia , Folhas de Planta/química , Selênio/farmacologia
17.
Clin Colorectal Cancer ; 18(1): e69-e73, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30415988

RESUMO

BACKGROUND: According to the IDEA trial, 6-month adjuvant chemotherapy should remain the treatment standard in stage III T4 or N2 colon cancer. The relatively poor survival in this high-risk subgroup-a 3-year disease-free survival (DFS) rate of 65%-and the potential synergistic efficacy of 5-fluorouracil (5-FU), oxaliplatin, and irinotecan suggest that FOLFIRINOX may be a regimen of particular interest in this setting. PATIENTS AND METHODS: This multicenter international phase 3 trial (ClinicalTrials.gov NCT02967289) being conducted in 49 centers in France and Canada plans to randomize (1:1; minimization method) 640 patients aged 18 to 70 years with Eastern Cooperative Oncology Group performance status ≤ 1. Randomization occurs within 42 days (with treatment initiated within 56 days) after curative-intent R0 surgical resection of a pT4N1 or pT1-4N2 colon adenocarcinoma. Patients will be randomized to receive adjuvant modified FOLFIRINOX (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, irinotecan 180 mg/m2, and 5-FU 2.4 g/m2 over 46 hours) or modified FOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, 5-FU bolus 400 mg/m2, then 2.4 g/m2 over 46 hours) every 2 weeks for 24 weeks (12 cycles). Patients will be followed for 5 years after the end of adjuvant chemotherapy. A gain of 9% in 3-year DFS (primary end point) is expected (74% in the experimental arm vs. 65% in the control arm; α, 5% [2-sided log-rank test]; 1-ß, 80%). Secondary end points of this study include 2-year DFS, overall survival, and toxicity.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Neoplasias do Colo/patologia , Intervalo Livre de Doença , Fluoruracila/uso terapêutico , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Estadiamento de Neoplasias , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina/uso terapêutico , Taxa de Sobrevida
18.
Int J Ophthalmol ; 11(1): 18-24, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29375985

RESUMO

AIM: To study the effect of discoidin I-like domaincontaining protein 3 (EDIL3) depletion on the proliferation and epithelial-mesenchymal transition (EMT) in human lens epithelial cells (LECs). METHODS: RNA interference was used to inhibit the expression of EDIL3 in human LECs in vitro. The morphology of cells was observed using an inverted microscope. Cell proliferation was assessed using EdU kit. Cell migration was investigated using Transwell chamber and EMT of LECs was assessed using confocal microscope and Western blotting. The transforming growth factor ß (TGFß) pathway was investigated using Western blotting. RESULTS: The data showed that silencing EDIL3 expression changed LECs morphology and suppressed LECs proliferation (P<0.05) and migration (P<0.01). Furthermore, the result of Western blotting showed that EDIL3 depletion reduced the expression of α-smooth muscle actin (α-SMA) (P<0.001) and vimentin (P<0.01), while increased the expression of E-cadherin (P<0.001). EDIL3 depletion could suppress the phosphorylation of Smad2 (P<0.01) and Smad3 (P<0.01) and the activation of exracellular signal regulated kinase (ERK) (P<0.05). CONCLUSION: The findings indicate that EDIL3 might participate in the proliferation and EMT in LECs via TGFß pathway and may be a potential therapeutic target for the treatment of posterior capsule opacification.

19.
Semin Oncol ; 44(1): 24-33, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28395759

RESUMO

We conducted a multicenter proof of concept phase II trial in patients with advanced colorectal cancer receiving FOLFIRI-cetuximab regimens to explore individual drug tailoring using pharmacogenetics and pharmacokinetics (PK) monitoring. Patients were stratified by their pharmacogenetic/phenotypic status: the irinotecan dose was adjusted according to the number of TA tandem repeats in the UGT1A1 promoter, while the 5-fluorouracil (5-FU) dose was initially adjusted according to dihydropyrimidine dehydrogenase (DPD) activity at initial screening (5-FUODPM Tox) followed by PK-guided dose optimization (5-FUODPM Protocol). An advanced cetuximab PK/pharmacodynamics (PD) study was performed but dosage remained unchanged. Eighty-five patients receiving second-line chemotherapy were enrolled. Mean irinotecan doses at 3 months were 247 ± 50, 210 ± 53 and 140 ± 21 mg/m2 for those with 6/6 (33), 6/7 (26), and 7/7 (7) TATA repeats in the UGT1A1 promoter region, respectively. The 5-FU dose was initially reduced in four patients with DPD deficiency, but mean 5-FU dose at 3 months was 2,412 ± 364 mg/m2 (1,615-3,170 mg/m2). Grade 4 toxicities were not encountered and grade 4 neutropenia occurred in 6.8%, 5.9%, and 0% of patients with 6/6, 6/7, and 7/7 UGT1A1 genotypes. The objective response rate was 25.8% among the 85 patients, 57.3% in patients with tumors wild type (WT) for KRAS, and 25% in those whose tumor harbored a mutant-KRAS. Secondary resection of hepatic metastases was performed in 31.7% of patients. Median progression-free survival (PFS) for all 85 patients was 181 days and 200, 132, and 121 days for patients with 6/6, 6/7, and 7/7 UGT1A1 genotypes, respectively; these differences were not statistically different. In parallel, a strong relationship was shown between cetuximab AUC and regimen efficacy. We conclude that personalized drug tailoring when administering in FOLFIRI + cetuximab allows for safe and efficient individual dose intensification.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Cetuximab/administração & dosagem , Neoplasias/tratamento farmacológico , Medicina de Precisão , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Cetuximab/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Genótipo , Glucuronosiltransferase/genética , Humanos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Proteínas Proto-Oncogênicas p21(ras)/genética
20.
Microbiol Res ; 192: 21-29, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27664720

RESUMO

Pseudomonas aeruginosa ATCC 27853 and Pseudomonas sp. 593 use the phosphatidylcholine synthase pathway (Pcs-pathway) for the biosynthesis of phosphatidylcholine (PC). Both bacterial strains contain the phoA and lapA genes encoding alkaline phosphatases (ALP) and display strong ALP activities. The PhoA and LapA enzymes are thought to be independently secreted via the Xcp and Hxc type II secretion system (T2SS) subtypes, in which the Hxc system may act as a complementary mechanism when the Xcp pathway becomes limiting. Inactivation of the pcs gene in both bacteria abolished PC synthesis and resulted in approximately 50% less ALP activity in the cell-free culture. Analysis by western blotting showed that LapA protein content in the wild type and the pcs- mutant was unchanged in the cytoplasmic, periplasmic or extracellular protein fractions. In contrast, the PhoA protein in the pcs- mutant was less prevalent among extracellular proteins but was more abundant in the periplasmic protein fraction compared to the wild type. Semi- quantitative reverse transcriptase PCR showed that phoA, lapA and 12 xcp genes were equally expressed at the transcriptional level in both the wild types and the pcs- mutants. Our results demonstrate that the absence of PC in bacterial membrane phospholipids does not interfere with the transcription of the phoA and lapA genes but primarily affects the export of PhoA from the cytoplasm to the extracellular environment via the Xcp T2SS.


Assuntos
Fosfatase Alcalina/metabolismo , Fosfatidilcolinas/metabolismo , Pseudomonas/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Mutação , Transporte Proteico , Transcrição Gênica , Sistemas de Secreção Tipo II
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