41 research outputs found
Mechanical Insights into Activation of Peroxides by Quinones: Formation of Oxygen-Centered Radicals or Singlet Oxygen
In
this work, the mechanism of the activation of peroxides by quinones
has been investigated through quantum chemical calculations. Hydrogen
peroxide (H2O2), peroxomonosulfate (PMS), peracetic
acid (PAA), and CH3OOH were chosen as the model peroxides
and p-benzoquinone (p-BQ) and tetrachloro-1,4-benzoquinone
(TCBQ) as the model quinones. The nucleophilic attack of peroxides
can occur on the carbonyl and olefinic carbons of quinones. For p-BQ, the nucleophilic attack of HO2–, CH3OO–, PMS, and PAA might prefer
to occur on the carbonyl carbons, which have more positive atomic
charges. Then, further transformation could not be induced from the
addition of HO2– and CH3OO– to p-BQ. Comparatively, singlet oxygen
(1O2) could be generated in the cases of PMS
and PAA. For TCBQ, the chlorine atoms cause the olefinic carbons to
carry more positive atomic charges, and then, HO2– preferred to add to the olefinic carbons, which might induce the
formation of the hydroxyl radical (•OH). The activation
of PMS by TCBQ was similar to that by p-BQ, with
the kinetical feasibility of 1O2 formation.
These findings may provide some theoretical insights into the reaction
of peroxides with quinones, especially into the interconnection between
the substitutes and the formation of oxygen-centered radicals (e.g., •OH) and 1O2
Abatement of Aromatic Contaminants from Wastewater by a Heat/Persulfate Process Based on a Polymerization Mechanism
A novel
approach to the abatement of pollutants consisting
of their
conversion to separable solid polymers is explored by a heat/persulfate
(PDS) process for the treatment of high-temperature wastewaters. During
this process, a simultaneous decontamination and carbon recovery can
be achieved with minimal use of PDS, which is significantly different
from conventional degradation processes. The feasibility of this process
is demonstrated by eight kinds of typical organic pollutants and by
a real coking wastewater. For the treatment of the selected pollutants,
30.2–91.9% DOC abatement was achieved with 24.8–91.2%
carbon recovery; meanwhile, only 5.2–47.0% of PDS was consumed
compared to a conventional degradation process. For the treatment
of a real coking wastewater, 71.0% DOC abatement was achieved with
66.0% carbon recovery. With phenol as a representative compound, our
polymerization-based heat/PDS process is applicable in a wide pH range
(3.5–9.0) with a carbon recovery of >87%. Both SO4•– and HO• can be initiators
for polymerization, with different contribution ratios under various
conditions. Phenol monomers are semioxidized to form phenolic radicals,
which are polymerized via chain transfer or chain growth processes
to form separable solid phenol polymers, benzenediol polymers, and
cross-linked polymers
miR-552 promotes laryngocarcinoma cells proliferation and metastasis by targeting p53 pathway
Numerous researches show that MicroRNAs (miRNAs) participate in tumorigenesis, progression, recurrence and drug resistance of malignant tumors, including laryngocarcinoma. miR-552 works as an oncogene in both colorectal cancer and liver cancer. However, the potential role of miR-552 in laryngocarcinoma is unknown. Herein, we for first found that miR-552 expression was upregulated in laryngocarcinoma tissues compared with their normal controls. Moreover, miR-552 expression was also increasing in the laryngocarcinoma cells. miR-552 interference inhibited the proliferation and metastasis of laryngocarcinoma cells in vitro and in vivo. Mechanically, bioinformatics and luciferase reporter analysis identified p53 as a direct target of miR-552. miR-552 knockdown upregulated the p53 mRNA and protein expression in laryngocarcinoma cells. miR-552 expression was negatively associated with p53 expression in laryngocarcinoma tissues. More importantly, the p53 siRNA or p53 overexpression virus abrogated the discrepancy of growth and metastasis capacity between miR-552 interference laryngocarcinoma cells and control cells.</p
DataSheet_1_Prognostic value of receptor tyrosine kinases in malignant melanoma patients: A systematic review and meta-analysis of immunohistochemistry.doc
BackgroundSubstantial evidence suggests that receptor tyrosine kinases (RTKs) are overexpressed in tumors; however, few studies have focused on the prognostic value of RTKs in melanoma.ObjectivesThe objective of this study is to evaluate the association between overexpression of RTKs and survival in melanoma patients based on immunohistochemistry (IHC) analysis.MethodsOur review is registered on PROSPERO (http://www.crd.york.ac.uk/PROSPERO), registration number CRD42021261460. Seven databases were searched, and data were extracted. We used IHC to measure the association between overexpression of RTKs and overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and clinicopathology in melanoma patients. Pooled analysis was conducted to assess the differences between Hazard Ratios along with 95% confidence intervals.ResultsOf 5,508 publications examined following the database search, 23 publications were included in this study, which included data from a total of 2,072 patients. Vascular endothelial growth factor receptor 2 (VEGF-R2) overexpression was associated with worse OS and DFS in melanoma. Furthermore, there was an association between OS and the expression of several RTKs, including epidermal growth factor receptor (EGFR), mesenchymal-epithelial transition factor (MET), vascular endothelial growth factor receptor 1 (VEGF-R1), and insulin-like growth factor 1 receptor (IGF-1R). There were no significant correlations between EGFR overexpression and worse DFS or PFS. EGFR overexpression was associated with worse OS cutaneous and nasal melanoma, but not uveal melanoma. However, MET overexpression was related to worse OS in both cutaneous and uveal melanoma. Furthermore, EGFR overexpression was associated with a worse OS in Europe compared to other geographic areas. Moreover, EGFR and MET overexpression showed significant prognostic value in patients with the cut-off “≥10% staining”.ConclusionsOur findings build concrete evidence that overexpression of RTKs is associated with poor prognosis and clinicopathology in melanoma, highlighting RTK expression has the potential to inform individualized combination therapies and accurate prognostic evaluation.</p
DataSheet_1_Cerebral Intraparenchymal Hemorrhage Changes Patients’ Gut Bacteria Composition and Function.pdf
Gut bacteria consists of 150 times more genes than humans that are vital for health. Several studies revealed that gut bacteria are associated with disease status and influence human behavior and mentality. Whether human brain injury alters the gut bacteria is yet unclear, we tested 20 fecal samples from patients with cerebral intraparenchymal hemorrhage and corresponding healthy controls through metagenomic shotgun sequencing. The composition of patients’ gut bacteria changed significantly at the phylum level; Verrucomicrobiota was the specific phylum colonized in the patients’ gut. The functional alteration was observed in the patients’ gut bacteria, including high metabolic activity for nutrients or neuroactive compounds, strong antibiotic resistance, and less virulence factor diversity. The changes in the transcription and metabolism of differential species were more evident than those of the non-differential species between groups, which is the primary factor contributing to the functional alteration of patients with cerebral intraparenchymal hemorrhage.</p
Table_4_Cerebral Intraparenchymal Hemorrhage Changes Patients’ Gut Bacteria Composition and Function.xls
Gut bacteria consists of 150 times more genes than humans that are vital for health. Several studies revealed that gut bacteria are associated with disease status and influence human behavior and mentality. Whether human brain injury alters the gut bacteria is yet unclear, we tested 20 fecal samples from patients with cerebral intraparenchymal hemorrhage and corresponding healthy controls through metagenomic shotgun sequencing. The composition of patients’ gut bacteria changed significantly at the phylum level; Verrucomicrobiota was the specific phylum colonized in the patients’ gut. The functional alteration was observed in the patients’ gut bacteria, including high metabolic activity for nutrients or neuroactive compounds, strong antibiotic resistance, and less virulence factor diversity. The changes in the transcription and metabolism of differential species were more evident than those of the non-differential species between groups, which is the primary factor contributing to the functional alteration of patients with cerebral intraparenchymal hemorrhage.</p
Table_7_Cerebral Intraparenchymal Hemorrhage Changes Patients’ Gut Bacteria Composition and Function.xls
Gut bacteria consists of 150 times more genes than humans that are vital for health. Several studies revealed that gut bacteria are associated with disease status and influence human behavior and mentality. Whether human brain injury alters the gut bacteria is yet unclear, we tested 20 fecal samples from patients with cerebral intraparenchymal hemorrhage and corresponding healthy controls through metagenomic shotgun sequencing. The composition of patients’ gut bacteria changed significantly at the phylum level; Verrucomicrobiota was the specific phylum colonized in the patients’ gut. The functional alteration was observed in the patients’ gut bacteria, including high metabolic activity for nutrients or neuroactive compounds, strong antibiotic resistance, and less virulence factor diversity. The changes in the transcription and metabolism of differential species were more evident than those of the non-differential species between groups, which is the primary factor contributing to the functional alteration of patients with cerebral intraparenchymal hemorrhage.</p
Table_2_Cerebral Intraparenchymal Hemorrhage Changes Patients’ Gut Bacteria Composition and Function.xls
Gut bacteria consists of 150 times more genes than humans that are vital for health. Several studies revealed that gut bacteria are associated with disease status and influence human behavior and mentality. Whether human brain injury alters the gut bacteria is yet unclear, we tested 20 fecal samples from patients with cerebral intraparenchymal hemorrhage and corresponding healthy controls through metagenomic shotgun sequencing. The composition of patients’ gut bacteria changed significantly at the phylum level; Verrucomicrobiota was the specific phylum colonized in the patients’ gut. The functional alteration was observed in the patients’ gut bacteria, including high metabolic activity for nutrients or neuroactive compounds, strong antibiotic resistance, and less virulence factor diversity. The changes in the transcription and metabolism of differential species were more evident than those of the non-differential species between groups, which is the primary factor contributing to the functional alteration of patients with cerebral intraparenchymal hemorrhage.</p
Tuning the First Hyperpolarizabilities of Boron Nitride Nanotubes
Various
carbon-substituted boron nitride (8,0) and (4,4) nanotubes
are designed for application as nonlinear optical materials. The structure
and first (static and frequency-dependent) hyperpolarizabilities of
these boron nitride nanotubes are predicted. The substitution of carbon
in the boron nitride nanotube clip significantly enhances the first
hyperpolarizabilities by up to several orders of magnitude. The doping
pattern of the carbon circle and π electron conjugation are
crucial in determining the large first hyperpolarizabilities of these
nanotubes
Chrysophanol Induced Glioma Cells Apoptosis via Activation of Mitochondrial Apoptosis Pathway
Glioma is a common intracranial tumor originated from neuroglia cell. Chrysophanol is an anthraquinone derivative proved to exert anticancer effects in various cancers. This paper investigated the effect and mechanism of chrysophanol in glioma. Glioma cell lines U251 and SHG-44 were adopted in the experiments. The cells were treated with chrysophanol at different concentrations (0, 10, 20 50, 100 and 200 μM) for 48 h in the study, and then processed with MitoTempo. Mitochondria and cytosol were isolated to investigate the role of mitochondria during chrysophanol functioning on glioma cells. Cell viability was detected through 3-(4,5-Dimethyl-2-Thiazolyl)-2,5-Diphenyl Tetrazolium Bromide (MTT) assay, and cell apoptosis, cell cycle as well as relative reactive oxygen species (ROS) were assessed by flow cytometry. Expressions of Cytosol Cyt C, cleaved caspase-3, cleaved caspase-9, Cyclin D1 and Cyclin E were evaluated by western blot. In U251 and SHG-44 cells, with chrysophanol concentration rising, cell viability, expressions of Cyclin D1 and Cyclin E were decreased while cell apoptosis, levels of cleaved caspase-3, cleaved caspase-9 and Cytosol Cyt C as well as ROS accumulation were increased with cell cycle arrested in G1 phase. Besides, chrysophanol promoted ROS accumulation, cell apoptosis and transfer of Cyt C from mitochondria to cytosol in cells while MitoTempo partly reversed the effect of chrysophanol. Chrysophanol promoted cell apoptosis via activating mitochondrial apoptosis pathway in glioma.</p
