Experimental study of the bilateral asymmetric single-rivet occluder device for transcatheter patent foramen ovale closure with reserved interatrial septal puncture area.

Purpose: To evaluate a noval bilateral asymmetric single-rivet occluder with reserved interatrial septal puncture area for treating patent foramen ovale (PFO). Materials and methods: The study established a pig model of patent foramen ovale (PFO) by puncturing the oval fossa and then performing high-pressure balloon dilation. A specially designed bilateral asymmetric occluder for the reserved interatrial septal puncture area was then. used to close the PFO through catheter-based intervention. The pigs were kept for 3 months before undergoing a second catheter-based intervention, involving interatrial septal puncture using a newly developed occluder in the reserved interatrial septal puncture area. During 6 months, the experimental pigs underwent assessment using digital subtraction angiography (DSA), echocardiography, and histological evaluation. Results: A patent foramen ovale (PFO) model was successfully established in 6 pigs using the puncture atrial septum high-pressure balloon dilation method. The diameter of the unclosed PFO was measured (3.56 ± 0.25 mm). Using the newly developed occluder device, all 6 pigs with unclosed PFO underwent successful catheter-based closure surgeries, with intraoperative and postoperative transesophageal echocardiography showing excellent device positioning and complete closure without residual shunting. After 3 months of implantation, the catheter-based interatrial septal puncture was performed through the reserved interatrial septal puncture area, and all procedures were successful. Immediately following euthanasia, a histological examination revealed intact and undamaged occluder devices with visible puncture holes in the reserved interatrial septal puncture area. No fracture of the nitinol wire was observed, and the surface of the occluder device showed coverage of endothelial and connective tissues. Utilizing a bilateral asymmetric single-rivet occluder device implanted through the reserved interatrial septal puncture area has proven effective in closing PFO. After implantation, the occluder device allows subsequent interatrial septal puncture procedures through the reserved area. Conclusion: The novel occluder device demonstrated excellent closure performance, biocompatibility, and puncturability in the experiment. This indicates the feasibility of conducting further catheter-based interventions on the interatrial septum.

Protective effects of cordycepin against d-galactose-induced aging in rats: A view from the heart.

AIMS: Aging is a critical contributing factor for cardiovascular diseases. The d-galactose-induced accelerated aging model is comparable to physiological aging from the cellular to the physiological level. The d-galactose treatment induces mitochondrial dysfunction, increased reactive oxygen species (ROS) production, and upregulation of senescence-related genes. Cordycepin, a functional element in Chinese traditional medicine, has multiple beneficial effects as an antioxidant and ROS scavenger, and has been reported to be effective in a number of ischemia models. This paper aims to investigate the cardioprotective effects of cordycepin in the d-galactose accelerated aging model. METHODS: In the current study, we employed the d-galactose accelerated aging model to study the cardioprotective effect of cordycepin. Eight-week-old Sprague-Dawley rats, randomly divided into five groups, were given vehicle, d-galactose (150 mg/kg/day), and cordycepin at 5, 10, and 20 mg/kg per day. At the end of the 8-week treatment, rat cardiac structure and function were assessed with echocardiographic imaging and hemodynamic parameter analysis. RESULTS: Cordycepin upregulated the expression of Klotho in serum and heart tissues. The expressions of senescence markers ß-galactosidase, p21, and oxidative stress marker malondialdehyde (MDA) were downregulated by cordycepin treatment. Reduction of levels and activity of the antioxidant factors superoxide dismutase (SOD) and catalase (CAT) induced by by d-galactose treatment was ameliorated by cordycepin. Furthermore, cordycepin activated AMPK signaling in d-galactose-treated rats. After 8 weeks of treatment, we found that cordycepin improved myocardia contractility and hypertension caused by d-galactose treatment. Mechanistically, reduced expression of the Klotho protein SOD1 caused by d-galactose was recovered in rats co-treated with cordycepin. CONCLUSION: Cordycepin could protect against cardiac dysfunction in a d-galactose-induced aging rat model, suggesting the therapeutic cardioprotective potential of cordycepin in aging. Geriatr Gerontol Int 2022; 22: 433-440.

A robust TALENs system for highly efficient mammalian genome editing.

Recently, transcription activator-like effector nucleases (TALENs) have emerged as a highly effective tool for genomic editing. A pair of TALENs binds to two DNA recognition sites separated by a spacer sequence, and the dimerized FokI nucleases at the C terminal then cleave DNA in the spacer. Because of its modular design and capacity to precisely target almost any desired genomic locus, TALEN is a technology that can revolutionize the entire biomedical research field. Currently, for genomic editing in cultured cells, two plasmids encoding a pair of TALENs are co-transfected, followed by limited dilution to isolate cell colonies with the intended genomic manipulation. However, uncertain transfection efficiency becomes a bottleneck, especially in hard-to-transfect cells, reducing the overall efficiency of genome editing. We have developed a robust TALENs system in which each TALEN plasmid also encodes a fluorescence protein. Thus, cells transfected with both TALEN plasmids, a prerequisite for genomic editing, can be isolated by fluorescence-activated cell sorting. Our improved TALENs system can be applied to all cultured cells to achieve highly efficient genomic editing. Furthermore, an optimized procedure for genomic editing using TALENs is also presented. We expect our system to be widely adopted by the scientific community.

The hOGG1 Ser326Cys polymorphism and breast cancer risk: a meta-analysis.

It was reported that the functional polymorphism Ser326Cys in the human 8-oxoguanine DNA glycosylase gene was associated with breast cancer risk; however, the published studies have inconsistent conclusions. To elucidate the effect of hOGG1 Ser326Cys on the susceptibility to breast cancer, all available studies were collected in this meta-analysis. We extracted the data from 10 case-control studies that were published in the PubMed database from 2003 to 2008 using the search phrases "human 8-oxoguanine DNA glycosylase, hOGG1, OGG1, OGG, polymorphism, genetic variation, and breast cancer." This meta-analysis included 4,963 breast cancer cases and 4,776 control subjects. The results showed that individuals who carrying the hOGG1 326Cys allele in the additive model did not have significantly increased risk of breast cancer compared with those carrying the 326Ser allele (P = 0.47, OR = 1.02; 95% CI = 0.96-1.09); similarly, no significant association between the hOGG1 326Cys allele and breast cancer risk was found either in the recessive genetic model (P = 0.34, OR = 1.06; 95% CI = 0.94-1.18) for Cys/Cys versus Ser/Cys + Ser/Ser, or dominant genetic model (P = 0.78, OR = 1.01; 95% CI = 0.93-1.11) for Cys/Cys + Ser/Cys versus Ser/Ser. In the stratified analysis, the meta-analysis showed the association between hOGG1 326Cys allele in the additive model and breast cancer was significant in European subjects (P = 0.04, OR = 0.71; 95% CI = 0.51-0.98), and dominant genetic model (P = 0.004, OR = 0.44; 95% CI = 0.25-0.77). However, the association was not significant between this polymorphism and different menopausal status (premenopausal and postmenopausal) and the other ethnicities (Asians and Americans). The meta-analysis suggested that the hOGG1 326Cys allele plays a significant protective effect to breast cancer in European women.

[Study on the relationship between the resistance to MTX and the transport protein superfamily of ATP-binding cassette that induces multiple drug resistance].

A major problem, especially the multidrug resistance, in chemotherapy was the resistance to the chemotherapeutic agents. ATP-binding cassette transporter superfamily that mediated the efflux of drugs was involved in multidrug resistance. In order to understand the relationship between the resistance to MTX and the transport protein superfamily of ATP-binding cassette, and to investigate the mechanism of resistance to MTX, the study detected the expressions of mdr1, mrp1, mrp2, mrp3, mrp5, mrp6 and abcg2 that encoded the transport proteins by SuperArray analysis and the expressions of MRP1and MRP5 proteins by Western blot analysis. The results showed that the multidrug resistance proteins were the chief member of ATP-binding cassette transporter superfamily related to resistance to MTX. And the high expression levels of mrp1 and mrp5 were detected. Moreover, it revealed by SuperArray analysis that expression of mrp5 in MTX-resistant cells was significantly higher than that in normal mouse cells. Besides, corresponding excessive expression of MRP5 protein in MTX-resistant cells was also confirmed by Western blot. So, MRP5 could play important roles in the resistance to MTX and would be a new potential drug target.

The molecular mechanism of resistance to methotrexate in mouse methotrexate-resistant cells by cancer drug resistance and metabolism SuperArray.

Drug resistance is often a limiting factor in successful chemotherapy. Understanding of the molecular mechanism of resistance to methotrexate is important for optimal use as well as for the development of new drugs. Using standard cytogenetic techniques, double minutes (DMs) were detected in mouse methotrexate-resistant cell lines inducted in vitro in this study. Moreover, functional SuperArray, determining the regulation of gene expression corresponding to 96 genes involved in the metabolism of and the development of resistance to cancer drugs was used to study in detail the molecular mechanism of resistance to methotrexate. Significant higher expressions of many genes especially dhfr, mrp5, atm and p53 were detected in methotrexate-resistant cells than in normal mouse cells by SuperArray analysis and corresponding excessive expressions of DHFR, MRP5, ATM, and P53 proteins in methotrexate-resistant cells were also confirmed by Western blot analysis. The results in this study indicated that DHFR, MRP5, ATM, and P53 could play important roles in resistance to methotrexate and some of them would be new potential drug targets.

Proteomic analysis for the identification of proteins related to methotrexate resistance.

Methotrexate(MTX) is one of the most important and frequently used drugs in cancer therapy, but the efficacy of this drug is often compromised by the development of resistance in cancer cells. To seek and identify differentially expressed proteins related to MTX resistance and provide clues for the mechanism of MTX resistance, proteins from cell line MTX300 (resistant to 300 micromol/L MTX) and its control cell line 3T3R500 were separated by two-dimensional electrophoresis (2-DE). The colloidal Coomassie brilliant blue-stained 2-DE gels were subjected to image analysis, which revealed several spots with high levels of differential expression between MTX300 and 3T3R500. The protein spot with highest differential expression was submitted for tryptic peptide mass fingerprinting(PMF) for identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). MS analysis and database searches revealed it to be dihydrofolate reductase (DHFR), which was subsequently confirmed by Western blot. The result suggested that DHFR might play an important role in the MTX resistance.