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1.
Colloids Surf B Biointerfaces ; 241: 114042, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38924850

RESUMO

In the field of orthopedics, surgeons have long been facing the challenge of loosening of external fixation screws due to inherent material characteristics. Despite Polyetheretherketone (PEEK) being employed as an orthopedic implant material for many years, its bio-inert nature often hinders bone healing due to the limited bioactivity, which restricts its clinical applications. Herein, a new type of orthopedic implant (Sr-SPK) was developed by introducing strontium (Sr)-doped mesoporous bioactive glass (Sr-MBG) onto the surface of PEEK implants through a simple and feasible method. In vitro experiments revealed that Sr-SPK effectively promotes osteogenic differentiation while concurrently suppressing the formation of osteoclasts. The same results were validated in vivo with Sr-SPK significantly improving bone integration. Upon investigation, it was found that Sr-SPK promotes adhesion among bone marrow mesenchymal stem cells (BMSCs) thereby promoting osteogenesis by activating the regulation of actin cytoskeletal and focal adhesion pathways, as identified via transcriptome analysis. In essence, these findings suggest that the newly constructed Sr-doped biofunctionalized PEEK implant developed in this research can promote osteoblast differentiation and suppress osteoclast activity by enhancing cell adhesion processes. These results underline the immense potential of such an implant for wide-ranging clinical applications in orthopedics.

2.
Eur J Clin Pharmacol ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907884

RESUMO

BACKGROUND: This meta-analysis was dedicated to evaluating the effectiveness and safety of Atezolizumab plus Bevacizumab (Atez/Bev) and Lenvatinib (LEN) as first-line systematic therapy for unresectable hepatocellular carcinoma (u-HCC). METHODS: The prospective protocol for this study was registered with the PROSPERO (Registration number: CRD42022356874). Literature searches were conducted in PubMed, EMBASE database Cochrane Library, and Web Science to determine all clinical controlled studies that reported Atez/Bev and LEN for treating u-HCC. We. evaluated as primary end-point overall survival (OS) and progression-free survival (PFS), as well as other outcomes such as tumor response and adverse events (AEs).Quality assessment and data extraction of studies were conducted independently by three reviewers. Mean difference (MD) and odds ratio (OR) with 95% confidence interval (CI) were calculated using a fixed-effects or random-effects model. The meta-analysis was performed with RevMan 5.3 software. RESULTS: 12 retrospective cohort studies (RCSs) involving a total of 4948 patients were finally included. The results showed that compared with LEN, Atez/Bev can improve the patient's PFS (HR = 0.80, 95% CI: 0.72 ~ 0.88; p < 0.0001) and reduce the rate of overall AEs (OR = 0.46 95% CI: 0.38 ~ 0.55, p < 0.00001) and grade ≥ 3 AEs (OR = 0.43; 95% CI: 0.36 ~ 0.51, p < 0.00001), while there is no difference between OS and treatment responses rate (objective response rate, disease control rate, complete response, partial response, progressive disease, and stable disease) between two groups. In addition, the subgroup analysis shows that Atez/Bev can promote the OS of patients with viral hepatitis. (HR = 0.79, 95% CI: 0.67 ~ 0.95; p = 0.01), while LEN has an advantage in improving OS in patients with Child-Pugh grade B liver function (HR = 1.98, 95% CI: 1.50 ~ 2.63; p < 0.00001). CONCLUSION: Current evidence shows that compared with LEN, Atez/Bev has more advantages in PFS and safety in treating u-HCC and can improve the OS of patients with viral. LEN has advantages in improving the OS of patients with grade B liver function. However, more multicenter randomized controlled experiments are needed in the future to verify our results.

3.
Hortic Res ; 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35147161

RESUMO

Low temperature can affect the growth and development of plants through changes in DNA demethylation patterns. Another known effect of low temperature is the accumulation of anthocyanin pigments. However, it is not known whether the two phenomena are linked, specifically, whether DNA demethylation participates in anthocyanin accumulation in response to low-temperature stress. The ROS1 gene is involved in plant DNA demethylation and influences methylation levels in response to low temperature stress. In this study, using RNA sequencing, we detected that the transcription levels of MdROS1 correlate with the anthocyanin content, as well as with those of anthocyanin biosynthesis-related genes in apple (Malus domestica), at low temperatures. Genomic bisulfite sequencing showed that the methylation levels of the promoters of the anthocyanin related genes MdCHS, MdCHI, MdF3'H, MdANS, MdUFGT, and MdMYB10 decreased in apple leaves after low-temperature treatment. Similar expression and methylation results were also found in apple fruit. Transiently silencing MdROS1 in the leaves and fruit of apple cultivars inhibited the accumulation of anthocyanins and led to decreased expression of anthocyanin biosynthetic genes, and the opposite results were detected in MdROS1-overexpressing leaves and fruit. A promoter binding assay showed that the conserved RRD-DME domains of MdROS1 directly bind to the promoters of MdF3'H and MdUFGT. Taken together, these results suggest that ROS1 affects the anthocyanin biosynthetic pathway by decreasing the methylation level of anthocyanin-related gene promoters, thereby increasing their expression and increasing anthocyanin accumulation.

4.
Mitochondrial DNA B Resour ; 6(2): 519-521, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33628911

RESUMO

The complete mitochondrial genome of Syrphus ribesii was determined in this study. The double-stranded circular DNA molecule was 16,530 bp in length, containing 37 typical genes: 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and an A + T-rich region. Thirteen PCGs were 11,196 bp in size, encoding 3720 amino acids in total. All the PCGs started with ATN, except the COI used TTG as its initiation codon. Most PCGs terminated with standard codon TAA, while the COI ended with T and the ND5 ended with TA. The lrRNA and srRNA genes were 1341 bp and 793 bp in length, respectively. The A + T-rich region harbored some typical structures characteristic of the dipterans. The phylogenetic tree showed that Syrphus ribesii was closely related to Eupeodes corollae, and the Syrphidae and Pipunculidae constituted a monophyletic group within the Syrphoidea.

5.
Front Plant Sci ; 9: 704, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29915606

RESUMO

In higher plants, anthocyanins are protective secondary metabolites, which contribute to the color of leaves, stems, flowers, and fruits, and have been found to have an antioxidant role in human health. In this study, we determined the expression of McMYB10 and its specific E3 ubiquitin ligase, McCOP1, in crabapple leaves during the course of a day and in five leaf development stages. Interestingly, the results showed that the transcription level of McCOP1 genes was higher in daylight than at night, and the transcripts of McMYB10 presented a positive correlation with the transcription of McCOP1-1 and McCOP1-2 and anthocyanin accumulation in a crabapple cultivar with red-colored leaves. Several MYB transcription factor (TF) binding sites of the MYBCORE type were found in the McCOP1-1 and McCOP1-2 promoters, and we deduced that there may be a relationship between McMYB10 and McCOP1-1 and McCOP1-2 at the transcriptional level. Yeast one hybrid (Y1H) and electrophoretic mobility shift assays (EMSA) demonstrated that the McMYB10 TF binds specifically to the promoter of McCOP1-1 and McCOP1-2. Furthermore, increased levels of McMYB10 promoted anthocyanin biosynthesis and the expression level of McCOP1-1 and McCOP1-2 in crabapple leaves during continuous light treatments, and overexpression or silencing of McMYB10 in crabapple leaves and apple fruits also result in an increase or decrease, respectively, in the expression of McCOP1-1 and McCOP1-2 and in anthocyanin biosynthesis. Our results reveal a new self-regulation mechanism in where McMYB10 modulates its own expression by activating McCOP1-1 and McCOP1-2 expression to promote ubiquitination of the McMYB10 protein by McCOP1.

6.
Hortic Res ; 4: 17070, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263792

RESUMO

Anthocyanins are secondary metabolites in land plants that contribute to the colors of leaves and flowers, and are nutritionally valuable components of the human diet. The DFR gene plays an important role in the anthocyanin biosynthetic pathway. In this study, we investigated the regulation of DFR expression and in different Malus crabapple cultivars that show distinct patterns of leaf coloration, and how it influences leaf anthocyanin accumulation and coloration. Specifically, we studied the ever-red leaved cultivar 'Royalty', the ever-green leaved cultivar 'Flame' and the spring-red leaved cultivar 'Radiant'. RT-PCR analysis showed that the expression of McDFR1 correlated with the expression of a MYB transcription factor, McMYB10, and with anthocyanin accumulation. We isolated five McDFR1 promoter fragments from the three cultivars and identified four different fragments (F1-4) that were present either in several cultivars, or only in one. Yeast one-hybrid and electrophoretic mobility shift assay analyses showed that McMYB10 could bind to all the McDFR1 promoters, except McDFR1-Ra2. The F1, F2 and F3 fragments did not affect McMYB10 binding to the McDFR1 promoters; however, we found evidence that the F4 fragment suppressed binding, and that the MYBGAHV amino-acid sequence maybe an important cis-element for McMYB10 protein binding. This information has potential value for strategies to modify plant color through genetic transformation.

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