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Yuji Zhang

Bio: Yuji Zhang is an academic researcher from Northern Hospital. The author has contributed to research in topics: Atrial fibrillation & Medicine. The author has an hindex of 4, co-authored 7 publications receiving 119 citations.

Papers
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Journal ArticleDOI
TL;DR: Perioperative DATS treatment effectively ameliorates MI/R injury in type 1 diabetic setting by enhancing cardiac SIRT1 signaling, thus reducing myocardial apoptosis and eventually preserving cardiac function.
Abstract: Diallyl trisulfide (DATS) protects against apoptosis during myocardial ischemia-reperfusion (MI/R) injury in diabetic state, although the underlying mechanisms remain poorly defined. Previously, we and others demonstrated that silent information regulator 1 (SIRT1) activation inhibited oxidative stress and endoplasmic reticulum (ER) stress during MI/R injury. We hypothesize that DATS reduces diabetic MI/R injury by activating SIRT1 signaling. Streptozotocin (STZ)-induced type 1 diabetic rats were subjected to MI/R surgery with or without perioperative administration of DATS (40 mg/kg). We found that DATS treatment markedly improved left ventricular systolic pressure and the first derivative of left ventricular pressure, reduced myocardial infarct size as well as serum creatine kinase and lactate dehydrogenase activities. Furthermore, the myocardial apoptosis was also suppressed by DATS as evidenced by reduced apoptotic index and cleaved caspase-3 expression. However, these effects were abolished by EX527 (the inhibitor of SIRT1 signaling, 5 mg/kg). We further found that DATS effectively upregulated SIRT1 expression and its nuclear distribution. Additionally, PERK/eIF2α/ATF4/CHOP-mediated ER stress-induced apoptosis was suppressed by DATS treatment. Moreover, DATS significantly activated Nrf-2/HO-1 antioxidant signaling pathway, thus reducing Nox-2/4 expressions. However, the ameliorative effects of DATS on oxidative stress and ER stress-mediated myocardial apoptosis were inhibited by EX527 administration. Taken together, these data suggest that perioperative DATS treatment effectively ameliorates MI/R injury in type 1 diabetic setting by enhancing cardiac SIRT1 signaling. SIRT1 activation not only upregulated Nrf-2/HO-1-mediated antioxidant signaling pathway but also suppressed PERK/eIF2α/ATF4/CHOP-mediated ER stress level, thus reducing myocardial apoptosis and eventually preserving cardiac function.

76 citations

Journal ArticleDOI
TL;DR: The data suggest that the aggravation of fibrosis remodeling in women may be an important reason for the low success rate of AF catheter ablation when compared to men, and inhibiting the TGFβ/Smad3 pathway-mediated fibrosis could represent an interesting target for future therapeutic concepts to improve the success rate.
Abstract: The success rate of catheter ablation in atrial fibrillation (AF) is known to be lower in females than in males. However, while the exact mechanism for this phenomenon remains to be elucidated, tissue fibrosis may play an important role in this regard. It has been shown that fibrosis promotes AF and its recurrence, thereby substantially reducing the efficacy of catheter ablation in AF patients. Thus, we hypothesized that fibrosis may contribute to gender differences in the outcomes of AF catheter ablation. Here we systematically assessed pulmonary vein sleeves obtained from 166 patients with and without long-standing persistent-AF (LSP-AF) in order to identify gender-specific mechanistic differences in fibrosis remodeling of AF patients. Histological analysis revealed that the female LSP-AF group, rather than its male counterpart, had a higher degree of fibrosis when compared to the NON-AF group. Further analysis using microarray, immunohistochemistry and Western Blot displayed that gender differences in fibrosis remodeling of LSP-AF were mainly due to the inherent differential expression of fibrosis-related genes (n=32) and proteins (n=6). Especially, those related to the TGFβ/Smad3 pathway appeared to be up-regulated in the female LSP-AF group thus promoting an aggravation of fibrosis remodeling. In summary, our data suggest that the aggravation of fibrosis remodeling in women may be an important reason for the low success rate of AF catheter ablation when compared to men. Therefore, inhibiting the TGFβ/Smad3 pathway-mediated fibrosis could represent an interesting target for future therapeutic concepts to improve the success rate of AF catheter ablation in women.

47 citations

Journal ArticleDOI
TL;DR: Elevated mtDNA copy number in peripheral blood is shown to be a significant independent risk factor for PoAF and its potential role in arrhythmogenesis is explored.
Abstract: Oxidative stress has been considered to be an important factor contributing to postoperative atrial fibrillation (PoAF). Mitochondrial DNA (mtDNA) copy number in peripheral blood has been found to be associated with a patient's oxidative stress. Therefore, we sought to determine whether there was association between mtDNA copy number and the onset of atrial fibrillation. mtDNA copy numbers were measured using the quantitative real-time polymerase chain reaction in peripheral blood from 485 consecutive patients with sinus rhythm undergoing coronary artery bypass grafting. The blood was collected before surgery. In the cohort, the incidence of PoAF was 20.8% (101/485). The mean mtDNA copy number was significantly higher in patents with PoAF than in those with sinus rhythm (36.43 vs 16.63, p r = 0.449, p = 0.01). In conclusion, we showed that elevated mtDNA copy number in peripheral blood is associated with PoAF. Further investigation is needed to validate mtDNA copy number as a predictive biomarker for PoAF and to explore its potential role in arrhythmogenesis.

23 citations

Journal ArticleDOI
TL;DR: In this paper, the authors proposed that injecting calcium chloride (CaCl2) into the major atrial ganglionated plexi (GPs) during isolated coronary artery bypass grafting (CABG) can reduce the incidence of post-operative atrial fibrillation (POAF) by calcium-induced autonomic neurotoxicity.

21 citations

Journal ArticleDOI
TL;DR: Compared the gene expression of human adult ventricular cardiomyocytes (AC16) under hypothermia is compared to find differences between different temperatures, and elucidate the candidate genes that may play important roles in the response to Hypothermia.

12 citations


Cited by
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TL;DR: This is a paid internship where interns work directly to assist the Director of Marketing and Communications on various tasks relating to upcoming GRA events.
Abstract: OVERVIEW The GRA Marketing Internship Program is offered to students who are interested in gaining valuable work experience through efforts in marketing, membership, sales, and events. Interns work directly to assist the Director of Marketing and Communications on various tasks relating to upcoming GRA events. During this internship, students will work a minimum of 10 hours a week and a maximum of 20 hours a week. Students are encouraged to earn credit for their internship, however this is a paid internship. Students interested in obtaining credit for their internship must consult their academic advisor or the intern coordinator at their academic unit.

1,309 citations

Journal ArticleDOI
TL;DR: The mechanisms underlying the development of diabetic cardiomyopathy and heart failure in type 1 and type 2 diabetes mellitus are discussed, the evidence from preclinical and clinical studies are summarized, and signalling pathways that might be potential therapeutic targets are described.
Abstract: The pathogenesis and clinical features of diabetic cardiomyopathy have been well-studied in the past decade, but effective approaches to prevent and treat this disease are limited. Diabetic cardiomyopathy occurs as a result of the dysregulated glucose and lipid metabolism associated with diabetes mellitus, which leads to increased oxidative stress and the activation of multiple inflammatory pathways that mediate cellular and extracellular injury, pathological cardiac remodelling, and diastolic and systolic dysfunction. Preclinical studies in animal models of diabetes have identified multiple intracellular pathways involved in the pathogenesis of diabetic cardiomyopathy and potential cardioprotective strategies to prevent and treat the disease, including antifibrotic agents, anti-inflammatory agents and antioxidants. Some of these interventions have been tested in clinical trials and have shown favourable initial results. In this Review, we discuss the mechanisms underlying the development of diabetic cardiomyopathy and heart failure in type 1 and type 2 diabetes mellitus, and we summarize the evidence from preclinical and clinical studies that might provide guidance for the development of targeted strategies. We also highlight some of the novel pharmacological therapeutic strategies for the treatment and prevention of diabetic cardiomyopathy.

295 citations

Journal ArticleDOI
TL;DR: All known types of cfNAs which are known to be present in biological fluids and could be involved in further studies to find out the exact biological role of them in normal physiological and pathological conditions are collected.
Abstract: Liquid biopsy is becoming a very popular sample obtaining procedure, replacing the invasive sampling methods for the diagnostic protocols. The advantages of this method include the possibility to isolate cell-free nucleic acids (cfNAs) for diagnostic or screening purposes. A comprehensive review combining all current and perspective applications of cell-free nucleic acids is missing. Published articles are dealing with one type of cfNAs, or discuss them from the perspective of single disorder. We collected here all known types of cfNAs which are known to be present in biological fluids and could be involved in further studies to find out the exact biological role of them in normal physiological and pathological conditions. Beyond doubt, cfNAs will have a tremendous effect in future screening, diagnosis, prognosis, follow-up and treatment of cardiovascular diseases, cancer, diabetes and other diseases.

148 citations

Journal ArticleDOI
TL;DR: Tilianin could attenuate MIRI by improving mitochondrial energy metabolism and reducing oxidative stress via AMPK/SIRT1/PGC-1 alpha signaling pathway, and were respectively abolished by Compound C and EX-527.

118 citations

Journal ArticleDOI
TL;DR: The approach to management of atrial fibrillation differs between women and men, and there are sex differences in response to medical therapy and catheter ablation.
Abstract: Atrial fibrillation is the most common sustained cardiac arrhythmia. The scope and impact of atrial fibrillation are wide; it can affect cardiac function, functional status, and quality of life, and it confers a stroke risk. There are sex differences in atrial fibrillation across the scope of the disease process, from epidemiology and causative mechanisms to management and outcomes. The approach to management of atrial fibrillation differs between women and men, and there are sex differences in response to medical therapy and catheter ablation. There are many gaps in our knowledge of the gender differences in atrial fibrillation, and many opportunities for future research.

113 citations