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1.
J Oral Sci ; 62(1): 57-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31996524

RESUMO

Porphyromonas gingivalis (P. gingivalis) is one of the major pathogenic bacteria of periodontitis or peri-implantitis. P. gingivalis tends to attach to the implant's neck with the formation of biofilm, leading to peri-implantitis. d-arginine has been shown to have a potential antimicrobial role. In this study, P. gingivalis was cultured in Brain Heart Infusion broth together with d-arginine. After 3 days (inhibition) or 6 days (dissociation), these were characterized using crystal violet (CV) staining for the biofilm, extracellular polysaccharide (EPS) production from the biofilm, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for biofilm activation. Furthermore, the P. gingivalis biofilm was observed by scanning electron microscopy (SEM). d-arginine effectively reduced biomass accumulation and promoted dissociation at concentrations of ≥50 mM and 100 mM, respectively. Through CV staining, d-arginine concentrations of EPS production from the biofilm for inhibition and dissociation effects was ≥50 mM and 100 mM, respectively. In addition, d-arginine affected biofilm activation for the corresponding concentrations: ≥60 mM for inhibition and ≥90 mM for dispersal. Under SEM observation, d-arginine changed the P. gingivalis biofilm structure in relatively high concentrations for inhibition or dissociation, respectively. The authors concluded that d-arginine could inhibit the formation of P. gingivalis biofilm and promote the dissociation of P. gingivalis biofilm.


Assuntos
Peri-Implantite , Porphyromonas gingivalis , Arginina , Biofilmes , Humanos , Microscopia Eletrônica de Varredura
2.
Environ Microbiol ; 22(1): 329-342, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31691434

RESUMO

Thermoprofundales (Marine Benthic Group D archaea, MBG-D) is a newly proposed archaeal order and widely distributed in global marine sediment, and the members in the order may play a vital role in carbon cycling. However, the lack of pure cultures of these oeganisms has hampered the recognition of their catabolic roles. Here, by constructing high-quality metagenome-assembled genomes (MAGs) of two new subgroups of Thermoprofundales from hydrothermal sediment and predicting their catabolic pathways, we here provide genomic evidences that Thermoprofundales are capable of degrading aromatics via the phenylacetic acid (PAA) pathway. Then, the gene sequences of phenylacetyl-CoA ligase (PCL), a key enzyme for the PAA pathway, were searched in reference genomes. The widespread distribution of PCL genes among 14.9% of archaea and 75.9% of Thermoprofundales further supports the importance of the PAA pathway in archaea, particularly in Thermoprofundales where no ring-cleavage dioxygenases were found. Two PCLs from Thermoprofundales MAGs, PCLM8-3 and PCLM10-15 , were able to convert PAA to phenylacetyl-CoA (PA-CoA) in vitro, demonstrating the involvement of Thermoprofundales in aromatics degradation through PAA via CoA activation. Their acid tolerance (pH 5-7), high-optimum temperatures (60°C and 80°C), thermostability (stable at 60°C and 50°C for 48 h) and broad substrate spectra imply that Thermoprofundales are capable of transforming aromatics under extreme conditions. Together with the evidence of in situ transcriptional activities for most genes related to the aromatics pathway in Thermoprofundales, these genomic, and biochemical evidences highlight the essential role of this ubiquitous and abundant archaeal order in the carbon cycle of marine sediments.

3.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4129-4133, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872689

RESUMO

Traditional Chinese medicine is planted in mountainous areas with suitable natural conditions. The planting area is complex in terrain,and the planting plots are mostly irregularly shaped. It is difficult to accurately calculate the planting area by traditional survey methods. The method of extracting Chinese herbal medicine planting area combined with remote sensing and GIS technology is of great significance for the rational development and utilization of traditional Chinese medicine resources. Taking Bletilla striata planting in Ningshan county of Shaanxi province as an example,the extraction method of planting area of traditional Chinese medicine in county was studied. High-resolution ZY-3 and GF-1 multi-spectral multi-temporal remote sensing images were used as data sources. Through field sampling,samples such as B. striata,cultivated land,forest land,water body,artificial surface,alpine meadow,etc. are collected. The spectral features,texture features and shape features of remotely identifiable objects in different planting areas and cultivated land,vegetable sheds were analyzed,confusing ground objects were eliminated and interpretation marks were establish. The method of visual interpretation is used to realize the extraction of B. striata planting areas,and the B. striata planting area are calculated by combining GIS technology. The results showed that the method of visual interpretation,using high-resolution ZY-3 and GF-1 multi-spectral multi-temporal remote sensing image data extracted the planting area of 403.05 mu. It can effectively extract the B. striata planting area in research region.


Assuntos
Medicina Tradicional Chinesa , Orchidaceae , Tecnologia de Sensoriamento Remoto , Florestas
4.
Brain ; 142(12): 3713-3727, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31633155

RESUMO

Acetylcholine receptor deficiency is the most common form of the congenital myasthenic syndromes, a heterogeneous collection of genetic disorders of neuromuscular transmission characterized by fatiguable muscle weakness. Most patients with acetylcholine receptor deficiency respond well to acetylcholinesterase inhibitors; however, in some cases the efficacy of acetylcholinesterase inhibitors diminishes over time. Patients with acetylcholine receptor deficiency can also benefit from the addition of a ß2-adrenergic receptor agonist to their medication. The working mechanism of ß2-adrenergic agonists in myasthenic patients is not fully understood. Here, we report the long-term follow-up for the addition of ß2-adrenergic agonists for a cohort of patients with acetylcholine receptor deficiency on anticholinesterase medication that demonstrates a sustained quantitative improvement. Coincidently we used a disease model to mirror the treatment of acetylcholine receptor deficiency, and demonstrate improved muscle fatigue, improved neuromuscular transmission and improved synaptic structure resulting from the addition of the ß2-adrenergic agonist salbutamol to the anticholinesterase medication pyridostigmine. Following an initial improvement in muscle fatiguability, a gradual decline in the effect of pyridostigmine was observed in mice treated with pyridostigmine alone (P < 0.001). Combination therapy with pyridostigmine and salbutamol counteracted this decline (P < 0.001). Studies of compound muscle action potential decrement at high nerve stimulation frequencies (P < 0.05) and miniature end-plate potential amplitude analysis (P < 0.01) showed an improvement in mice following combination therapy, compared to pyridostigmine monotherapy. Pyridostigmine alone reduced postsynaptic areas (P < 0.001) and postsynaptic folding (P < 0.01). Combination therapy increased postsynaptic area (P < 0.001) and promoted the formation of postsynaptic junctional folds (P < 0.001), in particular in fast-twitch muscles. In conclusion, we demonstrate for the first time how the improvement seen in patients from adding salbutamol to their medication can be explained in an experimental model of acetylcholine receptor deficiency, the most common form of congenital myasthenic syndrome. Salbutamol enhances neuromuscular junction synaptic structure by counteracting the detrimental effects of long-term acetylcholinesterase inhibitors on the postsynaptic neuromuscular junction. The results have implications for both autoimmune and genetic myasthenias where anticholinesterase medication is a standard treatment.

5.
Math Biosci Eng ; 16(5): 6015-6033, 2019 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-31499750

RESUMO

With the rapid development of mobile internet and cloud computing, numerous digital me-dia files in mobile social networking and media sharing software have become the important carriers of steganography. However, these digital media files may be resampled by the media server when being pushed to the intelligent mobile terminals. The resampling of digital media files is a transfor-mation which enlarges or shrinks objects by a scale factor that is the same in all dimensions. In order to reduce embedding distortion while ensuring the correct extraction of secret messages under resam-pling mechanism, a steganographic coding scheme based on dither convolutional trellis is proposed in this paper. The resampling mapping is estimated with finite sample pairs. The resampling stego media files with secret messages embedded are generated from the estimated resampling cover media files by syndrome-trellis codes (STCs). According to the estimated resampling mapping, the dither convolutional trellis for one dimensional resampling is constructed to generate the source stego me-dia files from source cover media files and resampling stego media files. The steganographic coding scheme is also extended to the circumstance of two dimensional resampling such as image scaling. The experimental results show that the proposed steganographic scheme can achieve less embedding dis-tortion while ensuring the accuracy of secret messages extraction under multi-dimensional resampling mechanism.

6.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2338-2344, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418237

RESUMO

To obtain salt-alkali tolerant strains which could be potenially used to improve the quality of saline-alkali soil, soil samples collected from Dongying, Shandong Province were diluted and spread to modified Gibbson medium with pH 9 and salt concentration of 100 g·L-1. A total of 18 bacteria strains were obtained. By increasing salt concentration and pH, an extremely salt-alkali tole-rant strain N14 was screened which could grow at pH 12 and salt concentration of 20%. We analyzed the morphological, physiological and biochemical characters and 16S rDNA sequence of N14. The strain N14 was identified as Bacillus marmarensis. N14 bacterial fertilizer significantly increased the biomass of wheat, improved shoot height, fresh weight and dry weight by 21.8%, 57.9% and 41.7%, respectively. The addition of N14 bacterial fertilizer significantly increased the chlorophyll a, chlorophyll b and total chlorophyll in wheat by 36.4%, 20.0% and 31.7%, respectively. It significantly increased the activities of invertase, urease and alkaline phosphatase in saline-alkali soil by 23.2%, 68.8% and 106.5%, respectively. It also significantly increased the activities of superoxide dismutase, peroxidase and catalase in roots by 109.6%, 17.8% and 50%, respectively. The concentration of malondialdehyde in wheat roots was significantly reduced by 39.8%. This study provided an idea for the application of extreme salt-alkali tolerant bacteria and a way for improvement of saline-alkali soil.


Assuntos
Fertilizantes , Plantas Tolerantes a Sal/fisiologia , Triticum/fisiologia , Agricultura , Álcalis , Clorofila A , Solo , Microbiologia do Solo
7.
Int Immunopharmacol ; 76: 105845, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31470266

RESUMO

BACKGROUND: Extracellular matrix (ECM) comprising the environments of multicellular society has a dynamic network structure. Collagen is one of the ubiquitous components of ECM. Collagen affects the inflammatory response by regulating the release of pro-inflammatory cytokines from cells. Gelatin, denatured collagen found temporally in tissues, is supposed to be pathophysiologically involved in tissue remodeling, inflammation caused by tissue damage. Previous reports indicate that, phorbol myristate (PMA)-stimulated human U937 (lymphoma cell line) cells that are often used as macrophage-like cells, show cell aggregations when cultured on type I collagen (col I) or gelatin-coated dishes, accompanying the changes of production and release of proinflammatory factors. However, it still remains to be examined whether collagen and gelatin affects normal macrophages as well. AIM: This study aims to investigate the effect of col. I, the main component of collagenous protein and its denatured product, gelatin, on mouse peritoneal macrophages (MPMs). METHODS: MTT assay, flow cytometric analysis of ROS, biochemical detection of antioxidant levels, ELISA assay, and western blot were used. RESULTS: MPMs formed multicellular aggregates on col. I - and gelatin-coated dishes with a concentration- and time-dependent manner. Further studies showed that the culture on col. I and gelatin up-regulated the protein expression and secretion of pro-inflammatory molecules such as IL-1ß, TNFα and prostaglandin E2 (PGE2) in MPMs. The levels were higher in the cells on gelatin than those on col. I. ROS levels are significantly increased in the cells cultured on both col. I- and gelatin-coated dishes, accompanying decreased levels of antioxidant enzyme catalase (CAT) and anti-oxidant glutathione (GSH), and enhanced nuclear translocation of NF-κB. CONCLUSION: Col I - or gelatin-coated culture induced the formation of multicellular aggregates and increased production of NF-κB-associated pro-inflammatory molecules in MPMs through up-regulation of ROS levels.

8.
Clin Cancer Res ; 25(18): 5650-5662, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308060

RESUMO

PURPOSE: TP53 mutations are highly prevalent in head and neck squamous cell carcinoma (HNSCC) and associated with increased resistance to conventional treatment primarily consisting of chemotherapy and radiation. Restoration of wild-type p53 function in TP53-mutant cancer cells represents an attractive therapeutic approach and has been explored in recent years. In this study, the efficacy of a putative p53 reactivator called COTI-2 was evaluated in HNSCC cell lines with different TP53 status.Experimental Design: Clonogenic survival assays and an orthotopic mouse model of oral cancer were used to examine in vitro and in vivo sensitivity of HNSCC cell lines with either wild-type, null, or mutant TP53 to COTI-2 alone, and in combination with cisplatin and/or radiation. Western blotting, cell cycle, live-cell imaging, RNA sequencing, reverse-phase protein array, chromatin immunoprecipitation, and apoptosis analyses were performed to dissect molecular mechanisms. RESULTS: COTI-2 decreased clonogenic survival of HNSCC cells and potentiated response to cisplatin and/or radiation in vitro and in vivo irrespective of TP53 status. Mechanistically, COTI-2 normalized wild-type p53 target gene expression and restored DNA-binding properties to the p53-mutant protein in HNSCC. In addition, COTI-2 induced DNA damage and replication stress responses leading to apoptosis and/or senescence. Furthermore, COTI-2 lead to activation of AMPK and inhibition of the mTOR pathways in vitro in HNSCC cells. CONCLUSIONS: COTI-2 inhibits tumor growth in vitro and in vivo in HNSCC likely through p53-dependent and p53-independent mechanisms. Combination of COTI-2 with cisplatin or radiation may be highly relevant in treating patients with HNSCC harboring TP53 mutations.

9.
J Am Chem Soc ; 141(23): 9134-9139, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31131600

RESUMO

The flexible organic amine cations on the interfaces of two-dimensional (2D) hybrid organic-inorganic perovskite nanosheets could form relaxed structures, which would lead to exotic optoelectronic properties but are hard to understand. Here, the unusual interfacial relaxation of nanosheets exfoliated from an orthorhombic 2D lead halide perovskite, [(C6H5CH2NH3)2]PbCl4, is interrogated via ultrafast second-harmonic generation (SHG) spectroscopy. The in-plane SHG intensity anisotropy of these nanosheets is found to decrease with reducing layer thickness. Combined first-principles calculations and Monte Carlo simulations reveal that the induced second-order polarization arises primarily from the (C6H5CH2NH3)+ cations; and these organic amine cations form significantly reorganized conformations with decreasing nanosheet thickness due to weakened van der Waals interactions. Because the orientations of organic components at the interface determine their electric properties and specifically the dipolar susceptibility, the resulting structure leads to striking changes in the SHG properties.

10.
Zhen Ci Yan Jiu ; 44(3): 176-82, 2019 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-30945499

RESUMO

OBJECTIVE: To observe the effect of "Neiguan" (PC6)-electroacupuncture (EA) preconditioning on serum metabolites in myocardial ischemia-reperfusion injury (MIRI) rats, so as to reveal its mechanism underlying improvement of ischemic myocardium from metabonomics. METHODS: A total of 48 male SD rats were randomly divided into control, model, EA "Neiguan"(PC6) and EA "Hegu"(LI4) groups (n=12 rats/ group). Rats of the control group were just banded on animal boards for 30 min, once daily for 7 days. The MIRI model was established by occlusion of the left anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 1 h, and rats of the model group were also banded as those in the control group. Before modeling, EA (10 Hz/50 Hz, 1 mA) was applied to bilateral "Neiguan"(PC6) and "Hegu"(LI4) for 30 min, once daily for 7 successive days. After the treatment, serum samples were collected to be analyzed by proton nuclear magnetic resonance (1H NMR) spectroscopy. The orthogonal partial least squares discriminate analysis (PLS-DA) was employed to distinguish the serum differential metabolic profile of rats in different groups and identify potential biomarkers. RESULTS: After modeling, the ECG of model group and electroacupuncture groups showed T wave towering, and there was no obvious ST segment between R wave and T wave. The T wave decreased more than 0.2 mV after reperfusion, and there was no obvious ST segment. Compared with the control group, MIRI induced significant changes of metabolites in the serum including increase of acetoacetate acid, lectic acid, creatine, glycerol and glucose, and decrease of alanine, glutamine, glycerophosphoryl choline and phosphorylcholine. In comparison with the model group, PC6-EA preconditioning induced significant changes, including an increase of glucose, and a decrease of leucine,isoleucine, valine,3-hydroxybutyric acid,lactate,acetate,acetone,acetoacetate acid,pyruvic acid,glutamine,creatine and glycerol. There is no significant difference in metabolic patterns between "Hegu" group and model group. Metabolic pathway enrichment analysis indicated that the protective effect of PC6-EA pretreatment was realized mainly by regulating pathways of glycolysis, gluconeogenesis, citric acid metabolism, pyruvate metabolism, ketone body metabolism, etc. CONCLUSION: PC6-EA pretreatment has a role in regulating gluconeogenesis, pyruvate metabolism, amino metabolism, ketone body metabolism and energy metabolism in rats with MIRI, which maybe contribute to its protective effect on ischemic myocardium, but the specific metabolic pathways and mechanisms need being studied further.


Assuntos
Eletroacupuntura , Isquemia Miocárdica , Traumatismo por Reperfusão , Pontos de Acupuntura , Animais , Masculino , Metaboloma , Extratos Vegetais , Ratos , Ratos Sprague-Dawley
11.
Zhen Ci Yan Jiu ; 44(1): 31-6, 2019 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-30773859

RESUMO

OBJECTIVE: To observe the effect of "Neiguan" (PC6)-electroacupuncture (EA) or moxibustion (Moxi) pretreatment on myocardial apoptosis and expression of autophagy related proteins light chain (LC) 3-Ⅰ and LC3-Ⅱ in rats with myocardial ischemia/reperfusion injury (MIRI), so as to explore their mechanisms underlying improvement of MIRI. METHODS: Forty SD rats (half male and half female) were randomly divided into sham operation, model, ischemic preconditioning (IP), EA and Moxi groups (n=8 in each group). EA (10 Hz/50 Hz, 1 mA) or Moxi (ignited moxa stick) was respectively applied to bilateral "Neiguan" (PC6) for 20 min, once daily for 7 days. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery for 40 min, followed by reperfusion for 60 min. The ultrastructural changes and autophagy of myocardial cells were observed by electron microscopy (EM), and the myocardial cellular apoptosis [apoptotic index = (number of apoptotic cells/total number of cardiomyocytes)×100%] was detected by the terminal deoxyribonucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method. The expressions of LC3-Ⅰ and LC3-Ⅱ proteins (markers for autophagy) in myocardial tissue were detected by Western blot. RESULTS: Following MI, EM observation revealed a vague structure of cardiomyocytes and muscular horizontal grain, dissolution of myofibers, mitochondrial swelling, some autophagic vacuoles and autophagic lysosomes at different degrees and surrounded by a double membrane in the model group, these situations were apparently milder in the EA and Moxi groups. The apoptosis index, myocardial LC3-Ⅰ and LC3-Ⅱ protein expression levels, and the ratio of LC3-Ⅱ/Ⅰ were significantly increased in the model group relevant to the sham operation group (P<0.05). After the treatment, the apoptosis index, the expression level of myocardial LC3-Ⅱ protein and the ratio of LC3-Ⅱ/Ⅰ were considerably down-regulated in the IP, EA and Moxi groups in comparison with those in the model group (P<0.05). The effect of EA was obviously superior to those of IP and Moxi in down-regulating the apoptosis index (P<0.05), but obviously inferior to those of IP and Moxi in down-regulating the levels of LC3-Ⅱ and LC3-Ⅱ/Ⅰ (P<0.05). No significant changes were found in the expression of LC3-Ⅰ after IP, EA and Moxi interventions in comparison with the model group (P>0.05), and no significant differences were observed in the apoptosis index and levels of LC3-Ⅱ and LC3-Ⅱ/Ⅰ between the IP and Moxi groups (P>0.05).. CONCLUSION: Both EA and moxibustion pretreatments, similar to IP, have a positive role in reducing myocardiocyte apoptosis and regulating autophagy-related protein expression in MIRI rats, which maybe contribute to their protective effects on ischemic myocardium.


Assuntos
Autofagia , Eletroacupuntura , Moxibustão , Pontos de Acupuntura , Animais , Apoptose , Feminino , Masculino , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Ratos , Ratos Sprague-Dawley
12.
Laryngoscope ; 129(2): 387-395, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30325027

RESUMO

OBJECTIVE: To compare survival effects of comprehensive neck dissection (CND) and selective neck dissection (SND) for patients with nasopharyngeal carcinoma (NPC) with only regional failure. METHODS: A total of 294 recurrent T0N1-3M0 NPC patients who underwent neck dissection in Sun Yat-Sen University Cancer Center, Guangzhou, People's Republic of China, between January 1984 and February 2014, were enrolled in the survival and interaction analyses. Using propensity scores to adjust for potential prognostic factors, an additional well-balanced cohort of 210 patients was constructed by matching each patient who received SND with one patient who underwent CND (1:1); the differences were then compared between SND and CND in terms of overall survival (OS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), and distant metastasis-free survival (DMFS). RESULTS: Both univariate and multivariate analyses showed that SND was not inferior to CND (P > 0.05) but demonstrated that extracapsular spread (ECS) (hazard ratio [HR] 3.49, 95% confidence interval [CI] 2.30-5.29, P < 0.001), recurrent N stage (rN stage) (HR 1.96, 95% CI 1.29-2.97, P = 0.002), and positive margins (HR 3.67, 95% CI 2.40-5.62, P < 0.001) were independent poor prognostic factors for OS. The interaction effects between the dissection style and each independent factor were not significant for OS, LRFS, RRFS, or DMFS (P > 0.05). Furthermore, no survival differences were found between SND and CND in the case-matched cohort in terms of OS, LRFS, RRFS, or DMFS (P = 0.550, 0.930, 0.214, and 0.146, respectively). CONCLUSION: With a similar radical dissection extent around the tumor rather than dissection of extensive lymph region distal to the lesion, SND is not inferior to CND for patients with NPC with only cervical failure. ECS, rN stage, and positive margins were adverse independent prognostic factors for patients with NPC. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:387-395, 2019.


Assuntos
Carcinoma Nasofaríngeo/cirurgia , Neoplasias Nasofaríngeas/cirurgia , Esvaziamento Cervical/mortalidade , Esvaziamento Cervical/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Pescoço/patologia , Pescoço/cirurgia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Radioterapia Adjuvante/mortalidade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Connect Tissue Res ; 60(4): 323-334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30277081

RESUMO

Purpose: Our previous studies indicate that phorbol 12-myristate 13-acetate (PMA)-treated U937 cells cultured on collagen I-coated dishes express lowered production of pro-inflammatory mediators in parallel through reduced reactive oxygen species (ROS) levels. By contrast, PMA-treated U937 cells on gelatin, the denatured collagen, show enhanced production of pro-inflammatory mediators, mediated by up-regulating autophagy levels. The present study is aimed to investigate the effect of ROS levels in PMA-treated U937 cells cultured on gelatin-coated surface. Material and methods: MTT assay, flow cytometric analysis of ROS and autophagy, biochemical detection of antioxidant levels, enzyme-linked immunosorbent assay, and western blot were used. Results: Gelatin-coating increased ROS levels in PMA-treated U937 cells. Increased ROS levels are involved in the regulation of cell aggregation and the release of pro-inflammatory mediators in gelatin-coated culture. These results lead to the query about the crosstalk between the two positive regulators, the autophagy and ROS. Autophagy induction is attenuated by N-acetyl-L-cysteine treatment, but the treatment with autophagy inhibitor, 3-methyladenine, does not affect ROS levels, suggesting ROS are upstream of autophagy in the regulation axis of differentiated U937 cells on gelatin-coated surface. Further study confirmed that upregulation of autophagy was responsible for ROS-induced cell aggregation and production of pro-inflammatory mediators. Conclusion: The results suggest that gelatin-coating promotes the aggregation of PMA-treated U937 cells and the production of pro-inflammatory mediators by ROS-autophagy signaling pathway.

14.
Nat Prod Res ; 33(24): 3527-3532, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29923429

RESUMO

The fruit of Camptotheca acuminata, a kind of mainly medicinal plant, possesses good antitumor properties. In order to explore the bioactive compounds for the treatment of hepatocellular carcinoma, the study focused on the isolation of cytotoxic compounds from the fruit of Camptotheca acuminata, which led to the discovery of fourteen compounds, including one new triterpene, 3ß,20-dihydroxy-30α-methyl,17(29)-ß-epoxy-28-norlupane (1), together with thirteen known compounds (2-14). The structures of isolated compounds were demonstrated by spectroscopic methods including 1D and 2D NMR spectroscopy. Moreover, all triterpenes were evaluated for antiproliferative activities against two human hepatocellular carcinoma cell lines, HepG2 and Hep3B. Compound 3 showed the strongest cytotoxic activity against the HepG2 with IC50 value at 29.6 µM. Further study demonstrated that compound 3 exhibited cytotoxic activity through the induction of apoptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Camptotheca/química , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Frutas/química , Humanos , Neoplasias Hepáticas/patologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Plantas Medicinais/química , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química
15.
J Cancer Res Ther ; 14(Supplement): S1076-S1083, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539849

RESUMO

Objective: To systematically review the effect and safety of irinotecan plus cisplatin (IP) compared with etoposide plus cisplatin (EP) in patients with previously untreated extensive-stage small cell lung cancer (E-SCLC). Materials and Methods: Databases including PubMed, The Cochrane Library, EMBASE, China National Knowledge Infrastructure, VIP, and WanFang Data were searched for the randomized controlled trials (RCTs) about IP compared with EP in patients with previously untreated E-SCLC from the establishment to June 2016. Two reviewers independently screened literature, extracted data and assessed the methodological quality of included studies. Then meta-analysis was performed using RevMan 5.3 software (Cochrane Collaboration, Oxford, UK). Results: A total of 12 RCTs involving 2030 patients were finally included. Meta-analysis showed that compared with EP regimen, IP regimen significantly improved the 1- and 2-year survival rates of the patients with previously untreated E-SCLC (risk ratio [RR] = 1.16, 95% confidence interval [CI] [1.03-1.31], P = 0.02; RR = 1.79, 95% CI [1.22-2.61], P = 0.003, respectively). However, there was no significant difference between IP regimen and EP regimen in the objective response rate (ORR) (RR = 1.07, 95% CI [0.99-1.15], P = 0.10) and disease control rate (DCR) (RR = 1.03, 95% CI [0.96-1.10], P = 0.38). The incidence of Grade 3/4 leukopenia, neutropenia, anemia, and thrombocytopenia of IP regimen was sigificantly lower than EP regimen (all P < 0.05), the incidence of Grade 3/4 nausea/vomiting and diarrhea of IP regimen was sigificantly higher than EP regimen (all P < 0.05). Conclusion: IP regimen significantly improves the 1- and 2-year survival rates, but not significantly improves the ORR and DCR, compared with EP regimen in patients with previously untreated E-SCLC. IP regimen has less Grade 3 or 4 hematological adverse events. IP regimen is an alternative of EP regimen in patients with previously untreated E-SCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Irinotecano/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Cisplatino/uso terapêutico , Diarreia/induzido quimicamente , Diarreia/epidemiologia , Etoposídeo/uso terapêutico , Doenças Hematológicas/induzido quimicamente , Doenças Hematológicas/epidemiologia , Humanos , Incidência , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Náusea/induzido quimicamente , Náusea/epidemiologia , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/patologia , Taxa de Sobrevida , Resultado do Tratamento , Vômito/induzido quimicamente , Vômito/epidemiologia
16.
Cell ; 175(4): 1045-1058.e16, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388443

RESUMO

Protein N-glycosylation is a widespread post-translational modification. The first committed step in this process is catalysed by dolichyl-phosphate N-acetylglucosamine-phosphotransferase DPAGT1 (GPT/E.C. 2.7.8.15). Missense DPAGT1 variants cause congenital myasthenic syndrome and disorders of glycosylation. In addition, naturally-occurring bactericidal nucleoside analogues such as tunicamycin are toxic to eukaryotes due to DPAGT1 inhibition, preventing their clinical use. Our structures of DPAGT1 with the substrate UDP-GlcNAc and tunicamycin reveal substrate binding modes, suggest a mechanism of catalysis, provide an understanding of how mutations modulate activity (thus causing disease) and allow design of non-toxic "lipid-altered" tunicamycins. The structure-tuned activity of these analogues against several bacterial targets allowed the design of potent antibiotics for Mycobacterium tuberculosis, enabling treatment in vitro, in cellulo and in vivo, providing a promising new class of antimicrobial drug.


Assuntos
Antibióticos Antituberculose/farmacologia , Defeitos Congênitos da Glicosilação/metabolismo , Inibidores Enzimáticos/farmacologia , N-Acetilglucosaminiltransferases/química , Animais , Antibióticos Antituberculose/química , Sítios de Ligação , Defeitos Congênitos da Glicosilação/genética , Inibidores Enzimáticos/química , Feminino , Células HEK293 , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Camundongos , Simulação de Acoplamento Molecular , Mutação , N-Acetilglucosaminiltransferases/antagonistas & inibidores , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Ligação Proteica , Células Sf9 , Spodoptera , Tunicamicina/química , Tunicamicina/farmacologia , Uridina Difosfato Ácido Glucurônico/química , Uridina Difosfato Ácido Glucurônico/metabolismo
17.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3407-3415, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30325167

RESUMO

Anaerobic fermented organic materials fluid (AFOF) could alleviate apple replant diseases. In this study, bacteria from AFOF was screened which could antagonize the main pathogenic fungi (Fusarium solani, F. proliferatum, F. oxysporum, F. moniliforme). The effects of the antagonistic bacteria were verified by pot experiment. The results showed that AFOF could significantly inhibit the pathogenic fungi growth and reproduction. Four strains (L11, L12, L13, L14) with strong inhibition activity were obtained from AFOF by the confrontation test, with the highest inhibitory rate being up to 57.3%. All the four strains were Bacillus, with no obvious antagonism each other. Both antagonistic bacteria and methyl bromide fumigation could promote the biomass of Malus hupenhensis seedling compared with continuous cropping soil. Methyl bromide fumigation led to the best growth of M. hupenhensis seedling. The antagonistic bacteria cloud improve root activity, with root length and root tip number increased by 25.1% and 70.9%, respectively. Compared with the continuous cropping soil, antagonistic bacteria and methyl bromide fumigation effectively decreased soil fungi by 71.2% and 64.2%, respectively. Treatment with antagonistic bacteria increased soil bacteria and soil actinomycetes by 48.0% and 140.2%, respectively, indicating that soil microbial community was transformed to "bacteriatype". Treatment with methyl bromide fumigation could significantly reduce soil bacteria and soil actinomycetes, suggesting the antagonistic bacteria could inhibit the growth of pathogenic fungi in soil.


Assuntos
Malus , Bactérias , Biomassa , Fermentação , Fusarium , Doenças das Plantas , Plântula , Solo , Microbiologia do Solo
18.
Cancer Manag Res ; 10: 4523-4535, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349385

RESUMO

Background: Global data demonstrate minimal improvement in the survival rate for oral cavity cancer (OCC) patients. We wished to know whether or not clinical features and survival rate have changed over time for OCC patients receiving initial treatment and follow-up at a large cancer center in China. Methods: Clinical features and survival data were collected on patients diagnosed during the successive decades of 1960-1969 (n=253), 1970-1979 (n=497), 1980-1989 (n= 659), 1990-1999 (n=793), and 2000-2009 (n=1,160) at the Sun Yat-sen University Cancer Center. Results: Over time, the overall 5-year survival rate for OCC patients was 52.0%. According to tumor localization, this rate was 71.4% for lip cancer, 56.3% for oral tongue cancer, and 42.7% for other parts of the oral cavity. From the 1960s to the 2000s, the 5-year survival rate steadily improved from 47.8% to 55.6% (P<0.001). Survival steadily decreased with age and was higher for women than for men in the 3 most recent decades. The survival rate for male patients was constant over time, while the rate for female patients improved dramatically. Obvious trends in clinical features over time included the following: increasing age of patients, increasing proportions of localized disease at diagnosis, decreasing proportions of diagnoses of lip cancer, decreasing proportions of diagnoses of squamous cell carcinoma, and decreasing proportions of non-surgical treatment approaches. Conclusion: The survival rate has steadily improved for OCC patients at this cancer center.

19.
Biomed Res Int ; 2018: 8412098, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30175146

RESUMO

Cancer has become the leading cause of mortality since 2010 in China. Despite the remarkable advances in cancer therapy, a low survival rate is still a burden to the society. The antineoplastic activity of aqueous extracts of Cordyceps kyushuensis Kob (AECK) was measured in this study. Results showed that AECK can significantly inhibit the proliferation and viability of U937 and K562 when treated with different concentrations of AECK, and the IC50 values of U937 and K562 were 31.23 µg/ml and 62.5 µg/ml, respectively. Hoechst 33258 staining showed that AECK could cause cell shrinkage, chromatin, condensation, and cytoplasmic blebbing, and DNA ladder experiment revealed the evident feature of DNA fragmentation which showed that AECK could induce cell apoptosis. Moreover, AECK gave rise to intrinsic apoptosis through increasing the amount of Ca2+ and downregulating the expression of Bcl-2. Meanwhile, the level of Fas death receptor was elevated which indicated that AECK could lead to exogenous apoptosis in U937. The expressions of oncogene c-Myc and c-Fos were suppressed which manifested that AECK could negatively regulate the growth, proliferation, and tumorigenesis of U937 cells. This research presented the primary antitumor activity of AECK which would contribute to the widely use of Cordyceps kyushuensis Kob as a functional food and medicine.


Assuntos
Apoptose/efeitos dos fármacos , Cordyceps/química , China , Humanos , Células U937 , Receptor fas/metabolismo
20.
Phys Chem Chem Phys ; 20(38): 25016-25022, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30246198

RESUMO

Extensive first principles calculations were performed to study the structural and electrochemical features of Co3O4 during its lithiation process as an anode material for lithium-ion batteries (LIBs). We found that with up to 8 mol Li in Co3O4, the formed LinCo3O4 structures are stable for low Li concentrations of n ≤ 1, but obvious structure distortions and volume expansions occur for LinCo3O4 with n > 1. This may be the reason why Co3O4 has a high Li capability but low cycling life as a LIB anode. The ab initio molecular dynamics simulations for LinCo3O4 (n = 2, 4, 8) further suggest a two-step electrochemistry process of Co3O4 → CoO → Co upon the lithiation process. We detected a distorted surface structure as Li atoms react with the Co3O4(110) surface, which also reduces the rate capability of the Co3O4 anode.

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