Application of modified Yamane technique in intrascleral intraocular lens fixation combined with or without iris reconstruction.

AIMS: To explore the application and long-term clinical effects of modified Yamane technique in intrascleral intraocular lens (IOL) fixation combined with or without iris reconstruction. SETTINGS AND DESIGN: The data of patients receiving IOL fixation with modified Yamane technique in an ophthalmology department between December 2021 and August 2023 were analyzed retrospectively. The longest follow-up duration was > 12 months. METHODS AND MATERIAL: The trailing haptic was fixed with the needle before the leading haptic. The silicone haptic stoppers were used to stabilize the IOL when iris reconstruction was combined. Preoperative and postoperative best-corrected visual acuity (BCVA), corneal endothelial cells (CECs), postoperative intraocular pressure (IOP), surgical indications and methods, and postoperative complications were recorded. Anterior segment optical coherence tomography (OCT) was used to evaluate IOL decentration and tilt. The paired sample t-test or Wilcoxon rank sum test were used to compare the results of the same index before and after the operation. RESULTS: Twelve patients (12 eyes) were included in this cohort. There were 1 case of IOL dislocation, eight cases of lens dislocation or subluxation, and three cases of aphakia. Traumatic lens dislocation was the main cause of aphakia. Primary lens extraction was performed in previous surgeries, and all three were combined with pars plana vitrectomy (PPV). Four of 12 patients underwent IOL fixation and iris reconstruction. The mean age of participants was 63 ± 10.61 years. The mean BCVA increased from 0.89 ± 0.72 logMAR to 0.39 ± 0.56 logMAR at the last visit (p < 0.05). The postoperative relative refractive error was - 0.13 ± 0.42 D (-0.60 D to + 0.57 D). The OCT showed that the IOLs were well centered, with a mean decentration of 0.20 ± 0.13 mm and a mean tilt of 2.31°±0.93°. Ten patients did not experience any complications. CONCLUSIONS: The modified Yamane technique in IOL fixation surgery, especially combined with iris reconstruction, reduces operation difficulty, increases operational stability and safety, and improves postoperative visual acuity without serious intra- or postoperative complications. The long-term improvement effect was remarkable.

Mesenchymal Stem Cells Regulate Microglial Polarization via Inhibition of the HMGB1/TLR4 Signaling Pathway in Diabetic Retinopathy.

Diabetic retinopathy (DR) is recognized as the most prevalent retinal degenerative disorder. Inflammatory response usually precedes microvascular alteration and is the primary factor of diabetic retinopathy. Activated microglia express many pro-inflammatory cytokines that exacerbate retina inflammation and disruption. In the present study, we found that MSCs alleviated blood-retina barrier (BRB) breakdown in diabetic rats, as evidenced by reduced retinal edema, decreased vascular leakage, and increased occludin expression. The MSC-treated retinal microglia exhibited reduced expression of M1-phenotype markers in the diabetic rats, including inducible nitric oxide synthase (iNOS), CD16, and pro-inflammatory cytokines. On the other hand, MSCs increased the expression of M2-phenotype markers, such as arginase-1 (Arg-1), CD206, and anti-inflammatory cytokines. HMGB1/TLR4 signaling pathway is activated in DR and inhibited after MSC treatment. Consistent with in vivo evidence, MSCs drove BV2 microglia toward M2 phenotype in vitro. Overexpression of HMGB1 in microglia reversed the effects of MSC treatment, suggesting HMGB1/TLR4 pathway is necessary for MSCs' regulatory effects on microglia polarization. Collectively, MSCs exert beneficial effects on DR by polarizing microglia from M1 toward M2 phenotype via inhibiting the HMGB1/TLR4 signaling pathway.

MSC-Derived Small Extracellular Vesicles Alleviate Diabetic Retinopathy by Delivering miR-22-3p to Inhibit NLRP3 Inflammasome Activation.

PURPOSE: This study aimed to investigate the effect of mesenchymal stem cell (MSC)-derived small extracellular vesicles (sEVs) on diabetic retinopathy (DR) and its underlying mechanism. METHODS: In vivo, MSC-sEVs were injected intravitreally into diabetic rats to determine the therapeutic efficacy. In vitro, MSC-sEVs with/without miR-22-3p inhibition were cocultured with advanced glycation end-products (AGEs)-induced microglia with/without NLRP3 overexpression to explore the molecular mechanism. RESULTS: In vivo, MSC-sEVs inhibited NLRP3 inflammasome activation, suppressed microglial activation, decreased inflammatory cytokines levels in the retina, and alleviated DR as evidenced by improved histological morphology and blood-retinal barrier function. Based on miRNA sequencing of MSC-sEVs, bioinformatic software, and dual-luciferase reporter assay, miR-22-3p stood out as the critical molecule for the role of MSC-sEVs in regulating NLRP3 inflammasome activation. Diabetic rats had lower level of miR-22-3p in their retina than those of control and sEV-treated rats. Confocal microscopy revealed that sEV could be internalized by microglia both in vivo and in vitro. In vitro, compared with sEV, the anti-inflammation effect of sEVmiR-22-3p(-) on AGEs-induced microglia was compromised, as they gave a lower suppression of NLRP3 inflammasome activation and inflammatory cytokines. In addition, NLRP3 overexpression in microglia damped the anti-inflammatory effect of sEV. CONCLUSION: These results indicated that MSC-sEVs alleviated DR via delivering miR-22-3p to inhibit NLRP3 inflammasome activation. Our findings indicate that MSC-sEVs might be a potential therapeutic method for DR.

The Global Changes of N6-methyldeoxyadenosine in Response to Low Temperature in Arabidopsis thaliana and Rice.

N6-methyldeoxyadenosine (6mA) is a recently discovered DNA modification involved in regulating plant adaptation to abiotic stresses. However, the mechanisms and changes of 6mA under cold stress in plants are not yet fully understood. Here, we conducted a genome-wide analysis of 6mA and observed that 6mA peaks were predominantly present within the gene body regions under both normal and cold conditions. In addition, the global level of 6mA increased both in Arabidopsis and rice after the cold treatment. The genes that exhibited an up-methylation showed enrichment in various biological processes, whereas there was no significant enrichment observed among the down-methylated genes. The association analysis revealed a positive correlation between the 6mA level and the gene expression level. Joint analysis of the 6mA methylome and transcriptome of Arabidopsis and rice unraveled that fluctuations in 6mA levels caused by cold exposure were not correlated to changes in transcript levels. Furthermore, we discovered that orthologous genes modified by 6mA showed high expression levels; however, only a minor amount of differentially 6mA-methylated orthologous genes were shared between Arabidopsis and rice under low-temperature conditions. In conclusion, our study provides information on the role of 6mA in response to cold stress and reveals its potential for regulating the expression of stress-related genes.

Microwave ablation induces abscopal effect via enhanced systemic antitumor immunity in colorectal cancer.

Background: Thermal ablation is the primary procedure for the local treatment of lung metastases. It is known that radiotherapy and cryoablation can stimulate an abscopal effect, while the occurrence of abscopal effect induced by microwave ablation is less; the cellular and molecular mechanisms involved in the abscopal effect after microwave ablation should be further elucidated. Methods: CT26 tumor-bearing Balb/c mice were treated with microwave ablation with several combinations of ablation power and time duration. The growth of primary or abscopal tumors and the survival of mice were both monitored; moreover, immune profiles in abscopal tumors, spleens, and lymph nodes were examined by flow cytometry. Results: Microwave ablation suppressed tumor growth in both primary and abscopal tumors. Both local and systemic T-cell responses were induced by microwave ablation. Furthermore, the mice exhibiting significant abscopal effect after microwave ablation markedly elevated Th1 cell proportion both in the abscopal tumors and spleens. Conclusions: Microwave ablation at 3 w-3 min not only suppressed tumor growth in the primary tumors but also stimulated an abscopal effect in the CT26-bearing mice via the improvement of systemic and intratumoral antitumor immunity.

m6A mRNA modification promotes chilling tolerance and modulates gene translation efficiency in Arabidopsis.

N 6-methyladenosine (m6A), the most prevalent mRNA modification in eukaryotes, is an emerging player of gene regulation at transcriptional and translational levels. Here, we explored the role of m6A modification in response to low temperature in Arabidopsis (Arabidopsis thaliana). Knocking down mRNA adenosine methylase A (MTA), a key component of the modification complex, by RNA interference (RNAi) led to drastically reduced growth at low temperature, indicating a critical role of m6A modification in the chilling response. Cold treatment reduced the overall m6A modification level of mRNAs especially at the 3' untranslated region. Joint analysis of the m6A methylome, transcriptome and translatome of the wild type (WT) and the MTA RNAi line revealed that m6A-containing mRNAs generally had higher abundance and translation efficiency than non-m6A-containing mRNAs under normal and low temperatures. In addition, reduction of m6A modification by MTA RNAi only moderately altered the gene expression response to low temperature but led to dysregulation of translation efficiencies of one third of the genes of the genome in response to cold. We tested the function of the m6A-modified cold-responsive gene ACYL-COA:DIACYLGLYCEROL ACYLTRANSFERASE 1 (DGAT1) whose translation efficiency but not transcript level was reduced in the chilling-susceptible MTA RNAi plant. The dgat1 loss-of-function mutant exhibited reduced growth under cold stress. These results reveal a critical role of m6A modification in regulating growth under low temperature and suggest an involvement of translational control in chilling responses in Arabidopsis.

N4-acetyldeoxycytosine DNA modification marks euchromatin regions in Arabidopsis thaliana.

BACKGROUND: Direct analogs of chemically modified bases that carry important epigenetic information, such as 5-methylcytosine (m5C)/5-methyldeoxycytosine (5mC), 5-hydroxymethylcytosine (hm5C)/5-hydroxymethyldeoxycytosine (5hmC), and N6-methyladenosine (m6A)/N6-methyldeoxyadenosine (6mA), are detected in both RNA and DNA, respectively. The modified base N4-acetylcytosine (ac4C) is well studied in RNAs, but its presence and epigenetic roles in cellular DNA have not been explored. RESULTS: Here, we demonstrate the existence of N4-acetyldeoxycytosine (4acC) in genomic DNA of Arabidopsis with multiple detection methods. Genome-wide profiling of 4acC modification reveals that 4acC peaks are mostly distributed in euchromatin regions and present in nearly half of the expressed protein-coding genes in Arabidopsis. 4acC is mainly located around transcription start sites and positively correlates with gene expression levels. Imbalance of 5mC does not directly affect 4acC modification. We also characterize the associations of 4acC with 5mC and histone modifications that cooperatively regulate gene expression. Moreover, 4acC is also detected in genomic DNA of rice, maize, mouse, and human by mass spectrometry. CONCLUSIONS: Our findings reveal 4acC as a hitherto unknown DNA modification in higher eukaryotes. We identify potential interactions of this mark with other epigenetic marks in gene expression regulation.

Transcriptome-Wide Analysis of RNA m6A Methylation and Gene Expression Changes Among Two Arabidopsis Ecotypes and Their Reciprocal Hybrids.

The remodeling of transcriptome, epigenome, proteome, and metabolome in hybrids plays an important role in heterosis. N(6)-methyladenosine (m6A) methylation is the most abundant type of post-transcriptional modification for mRNAs, but the pattern of inheritance from parents to hybrids and potential impact on heterosis are largely unknown. We constructed transcriptome-wide mRNA m6A methylation maps of Arabidopsis thaliana Col-0 and Landsberg erecta (Ler) and their reciprocal F1 hybrids. Generally, the transcriptome-wide pattern of m6A methylation tends to be conserved between accessions. Approximately 74% of m6A methylation peaks are consistent between the parents and hybrids, indicating that a majority of the m6A methylation is maintained after hybridization. We found a significant association between differential expression and differential m6A modification, and between non-additive expression and non-additive methylation on the same gene. The overall RNA m6A level between Col-0 and Ler is clearly different but tended to disappear at the allelic sites in the hybrids. Interestingly, many enriched biological functions of genes with differential m6A modification between parents and hybrids are also conserved, including many heterosis-related genes involved in biosynthetic processes of starch. Collectively, our study revealed the overall pattern of inheritance of mRNA m6A modifications from parents to hybrids and a potential new layer of regulatory mechanisms related to heterosis formation.

Epigenetic map and genetic map basis of complex traits in cassava population.

Cassava (Manihot esculenta Crantz) is an important tropical starchy root crop that is adapted to drought but extremely cold sensitive. A cold-tolerant, high-quality, and robust supply of cassava is urgently needed. Here, we clarify genome-wide distribution and classification of CCGG hemi-methylation and full-methylation, and detected 77 much candidate QTLsepi for cold stress and 103 much candidate QTLsepi for storage root quality and yield in 186 cassava population, generated by crossing two non-inbred lines with female parent KU50 and male parent SC124 (KS population). We developed amplified-fragment single nucleotide polymorphism and methylation (AFSM) genetic map in this population. We also constructed the AFSM QTL map, identified 260 much candidate QTL genes for cold stress and 301 much candidate QTL genes for storage root quality and yield, based on the years greenhouse and field trials. This may accounted for a significant amount of the variation in the key traits controlling cold tolerance and the high quality and yield of cassava.

Promoter regulatory domain identification of cassava starch synthase IIb gene in transgenic tobacco.

Soluble starch synthase is a key enzyme in the starch biosynthesis pathway, and its enzyme activity significantly influences starch components in cassava storage root. However, studies on the regulation mechanism of soluble starch synthase gene are rare. In this study, we cloned the 5' flanking sequence of the MeSSIIb gene and predicted the distribution of cis-elements. The region from -453 to -1 was considered the primary core promoter by the quantitative detection of GUS activity in transgenic tobacco plants containing 5' truncated promoters fused with the GUS gene. Analysis results clarified that the region from -531 to -454 significantly repressed promoter activity. The region from -453 to -388 was a repressive domain of ethylene, and some unknown drought responsive cis-elements were located in the region from -387 to -1. These findings will provide useful information on the functional assay and transcriptional regulation mechanisms of the MeSSIIb gene.