Two novel flavoalkaloids, (-)-6-(5'''- S)- N-ethyl-2-pyrrolidinone-epigallocatechin- O-gallate (ester-type catechin pyrrolidinone A, etc-pyrrolidinone A, 1), (-)-6-(5'''- R)- N-ethyl-2-pyrrolidinone-epigallocatechin- O-gallate (etc-pyrrolidinone B, 2), and new naturally occurring flavoalkaloids, (-)-8- N-ethyl-2-pyrrolidinone-epigallocatechin- O-gallate (etc-pyrrolidinone C, 3a, and etc- pyrrolidinone D, 3b), were isolated from white tea ( Camellia sinensis). Their structures were identified by extensive nuclear magnetic resonance spectra. The absolute configuration of compounds 1 and 2 was decided by comprehensive circular dichroism spectroscopic analyses. The isolated flavoalkaloids together with (-)-epigallocatechin- O-gallate (EGCG) were evaluated for their inhibition against the formation of advanced glycation end products, with IC values ranging from 10.3 to 25.3 μM. Ultra performance liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry detected these flavoalkaloids in both white tea and fresh tea leaves, which demonstrated the existence of a corresponding biosynthetic pathway in tea plants. Therefore, a possible pathway was proposed to involve deamination, decarboxylation, and spontaneously cyclization of l-theanine and then attachment of the product to EGCG to form the flavoalkaloids.
Tumor necrosis factor-alpha (TNF-α) is a multifunctional pro-inflammatory cytokine that plays an important role in cancer development. We performed a meta-analysis to assess the relationship between single nucleotide polymorphisms in the TNF-α promoter region (rs1800629 and rs361525) and susceptibility to squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and melanoma. After database retrieval, article selection, data extraction, and quality assessment, 20 articles comprising 4865 cases and 6329 controls were included in this study. rs1800629 was associated with an increased overall risk of SCC, lung SCC, and oral SCC in the AA vs G and AA vs GG+GA genetic models (all OR>1, Passociation<0.05). No increased risk of skin SCC, skin BCC or melanoma was observed (all Passociation>0.05). Rs361525 was not associated with overall SCC risk in the allele, heterozygote, dominant, recessive, or carrier model (all Passociation>0.05). Begg's and Egger's tests (PBegg>0.05; PEgger>0.05) demonstrated there was no significant publication bias. These data indicate that the AA genotype of TNF-α rs1800629, but not rs361525, is associated with an increased risk of SCC, suggesting it could potentially serve as a prognostic marker for predicting SCC risk.
<p><strong>Abstract.</strong> Under strong atmospheric oxidization capacity, haze pollution in the summer of Beijing was the result of the synergistic effect of physicochemical process in the atmospheric boundary layer (ABL). The south/southwest areas generally ~&#8201;60&#8211;300&#8201;km far away from Beijing were seriously polluted, in contrast to a clean situation in Beijing. The southerly winds moving more than ~&#8201;20&#8211;30&#8201;km&#8201;h<sup>&#8722;1</sup> since early morning primarily caused the initiation of haze pollution. The PM<sub>2.5</sub> level increased to 75&#8201;&#956;g&#8201;m<sup>&#8722;3</sup> in several hours at daytime, which was simultaneously affected by the ABL structure. Additionally, the O<sub>3</sub> concentration was quite high at daytime (250&#8201;&#956;g&#8201;m<sup>&#8722;3</sup>), corresponding to a strong atmospheric oxidation capacity. Numerous sulfate and nitrate were formed through active atmospheric chemical processes, with sulfur oxidation ratio (SOR) up to ~&#8201;0.76 and nitrogen oxidation ratio (NOR) increasing from 0.09 to 0.26, which further facilitated the particulate matter (PM) level rising. Even so, the increase in sulfate was mainly linked by southerly transport. At midnight, the PM<sub>2.5</sub> concentration sharply increased from 75&#8201;&#956;g&#8201;m<sup>&#8722;3</sup> to 150&#8201;&#956;g&#8201;m<sup>&#8722;3</sup> in 4 hours and stayed the highest level till the next morning. With the premise of an extremely stable ABL structure, the formation of secondary aerosols dominated by nitrate was quite intense, driving the outbreak of haze pollution. PM levels in the south/southeast of Beijing were significantly lower than that in Beijing over this time, even below air quality standards, thus, the contribution of pollution transport was almost gone. With the formation of nocturnal stable boundary layer of 0&#8211;0.3&#8201;km altitude, the extremely low turbulence kinetic energy (TKE) of 0&#8211;0.05&#8201;m<sup>2</sup>&#8201;s<sup>&#8722;2</sup> inhibited the spread of particles and moisture, ending up with elevated levels of PM<sub>2.5</sub> and relative humidity (~&#8201;90&#8201;%) near the surface. Under quite high humidity and strong ambient oxidization capacity, the NOR rapidly increased from 0.26 to 0.60 and heterogeneous hydrolysis reactions at the moist particle surface were very significant. The nitrate concentration explosively increased from 11.6&#8201;&#956;g&#8201;m<sup>&#8722;3</sup> to 57.8&#8201;&#956;g&#8201;m<sup>&#8722;3</sup>, while the concentrations of sulfate and organics slightly increased by 6.1&#8201;&#956;g&#8201;m<sup>&#8722;3</sup> and 3.1&#8201;&#956;g&#8201;m<sup>&#8722;3</sup>, respectively. With clean & strong winds passing through Beijing, the stable ABL was broken with potential temperature gradient turning to negative and ABL heights increasing to ~&#8201;2.5&#8201;km. The strong turbulence activity with TKE of ~&#8201;3&#8211;5&#8201;m<sup>2</sup>&#8201;s<sup>&#8722;2</sup> notably promoted the pollution diffusion. The self-cleaning capacity of the atmosphere is always responsible for the dispersion of air pollution. Even so, reducing atmospheric oxidization capacity such as strengthening the collaborative control of nitrogen oxide (NO<sub>x</sub>) and volatile organic compounds (VOCs) was urgent, as well as continuously deepening regional joint control of air pollution.</p>
To study the mechanism of self-assembling short-peptide nano-fiber gel scaffolds on the aesthetic repair of burns. RADA16-1 assembled short-peptide nano-fiber gel scaffold was prepared using the ultrasonic method. Twenty female SD rats were randomly divided into two groups. Burn model was established using the electrical machinery method. The wound surface of the rats in the experimental group was coated with RADA16-1 and that of the rats in the control group was coated with NaCl. The degree of wound healing, hair follicle growth, hair growth length, and expression of bFGF and EGF were compared between the two groups. RADA16-1 fibers were broken into short fibers under the ultrasonic environment and then reorganized into gels. The degree of wound healing, hair follicle growth, hair growth length, and expression of bFGF and EGF in the experimental group were better than those in the control group. The assembly of short peptide nano-fiber gel scaffolds can effectively repair burn wounds.
Chromosomal instability (CIN) is closely associated to the early detection of several clinical tumours. In this study, the authors first established a novel prognostic model of melanoma using the hub genes of CIN, based on the datasets of The cancer genome atlas‐skin cutaneous melanoma (TCGA‐SKCM) and GSE65904 cohorts. Based on the risk scores of our model, the disease‐specific survival (DSS) prognosis was worse in the high‐risk group. Combining risk score, stage, age, ulceration, and clark factors, a Nomogram was generated to predict 1, 3, 5‐year survival rates, which indicated a good clinical validity. Our finding also showed a correlation between high/low risk and tumour infiltration levels of ‘activated CD8 T cells’ and ‘effector memory CD8 T cells’. Moreover, the authors first performed a CIN‐based tumour clustering analysis using TCGA‐SKCM cases, and identified two melanoma clusters, which exhibit the distinct DSS prognosis and the tumour‐infiltrating levels of CD8 T cells. Taken together, a promising CIN‐related prognostic signature and clustering for melanoma cases were first established in our study.
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