Liang Yin

In the realm of regenerative medicine, despite the various techniques available for inducing the differentiation of induced pluripotent stem (iPS) cells into cardiomyocytes, there remains a need to enhance the efficiency of this induction process. This study aimed to improve the differentiation efficiency of iPS-derived cardiomyocytes (iPS-CMs) by incorporating mechanical stretching. Human iPS cells were co-cultured with human gingival fibroblasts (HGF) on a polydimethylsiloxane (PDMS) stretch chamber, where mechanical stretching stimulation was applied during the induction of cardiomyocyte differentiation. The maturation of iPS-CMs was assessed using qRT-PCR, immunofluorescence staining, transmission electron microscopy, and contractility comparisons. Results indicated significantly elevated gene expression levels of cardiomyocyte markers (cTnT) and the mesodermal marker (Nkx2.5) in the stretch group compared to the control group. Fluorescent immunocytochemical staining revealed the presence of cardiac marker proteins (cTnT and HCN4) in both groups, with higher protein expression in the stretch group. Additionally, sarcomere length in the stretch group was notably larger than in the control group. A significant increase in the contractility of iPS-CMs was observed in the stretch group. These findings demonstrate that mechanical stretching stimulation enhances the maturity and differentiation efficiency of iPS-CMs co-cultured with fibroblasts.

To investigate the differences and their clinical significance in the intestinal microbiota in patients with Parkinson's disease (PD) in comparison to those in healthy controls. 20 patients with PD who received treatment in the First Affiliated Hospital of Bengbu Medical College between January 2019 and December 2019 were selected as the research subjects to form the PD group, while 20 age- and gender-matched healthy volunteers were selected as the control group. Fecal samples from the two groups were collected, and the V4 region of 16S-ribosomal ribonucleic acid was selected for high-throughput sequencing analysis to explore any differences, as well as their significance, in the intestinal microbiota abundance at the class, family, and genus levels between the two study groups. The operational taxonomic unit cluster analysis revealed a high degree of overlap between the patients with PD and the controls. Compared with the controls, the relative abundance of Coriobacteriia and Coriobacteriaceae was increased in the PD group (p < 0.01), while the relative abundance of Lachnospiraceae was significantly lower (p < 0.01). The relative abundance of Collinsella, Escherichia, and Fusobacterium in the PD group was significantly higher than in the control group (p < 0.05). Compared with the healthy subjects, the abundance of specific microflora was significantly different in the PD patients at the class, family, and genus level. Intestinal flora may act as a potential biomarker for PD and provide a theoretical basis for microflora transplantation therapy.

Lifestyle changes, such as overeating and underexercising, can increase the risk of prediabetes. Diabetes is one of the leading causes of atherosclerosis, and recently it became clear that the pathophysiology of atherosclerosis progresses even before the onset of diabetic symptoms. In addition to changes in platelets and leukocytes in the hyperglycemic state and damage to vascular endothelial cells, extracellular vesicles and microRNAs were found to be involved in the progression of prediabetes atherosclerosis. This review discusses the cellular and molecular mechanisms of these processes, with an intention to enable a comprehensive understanding of the pathophysiology of prediabetes and atherosclerosis.

A thrombus in a coronary artery causes ischemia, which eventually leads to myocardial infarction (MI) if not removed. However, removal generates reactive oxygen species (ROS), which causes ischemia–reperfusion (I/R) injury that damages the tissue and exacerbates the resulting MI. The mechanism of I/R injury is currently extensively understood. However, supplementation of exogenous antioxidants is ineffective against oxidative stress (OS). Enhancing the ability of endogenous antioxidants may be a more effective way to treat OS, and exosomes may play a role as targeted carriers. Exosomes are nanosized vesicles wrapped in biofilms which contain various complex RNAs and proteins. They are important intermediate carriers of intercellular communication and material exchange. In recent years, diagnosis and treatment with exosomes in cardiovascular diseases have gained considerable attention. Herein, we review the new findings of exosomes in the regulation of OS in coronary heart disease, discuss the possibility of exosomes as carriers for the targeted regulation of endogenous ROS generation, and compare the advantages of exosome therapy with those of stem-cell therapy. Finally, we explore several miRNAs found in exosomes against OS.

Background: Whether the benefits of early prophylactic anticoagulation by low molecular weight heparin (LMWH) would outweigh its possible harms in patients after minimally invasive cardiac surgery (MICS) remains contentious. The aims of this study were to define the incidence of venous thromboembolism (VTE) and to assess whether early prophylactic anticoagulation by LMWH postoperatively was indeed effective in reducing VTE without increasing risk of complications after MICS. Methods: This investigation was a single-center, retrospective, propensity score-matched analysis study. A total of 473 patients underwent MICS, of whom 257 received prophylactic anticoagulation with LMWH (LMWH group) in the early postoperative period and 216 were not treated with LMWH (Control group). The main outcome measurements included the incidence of embolism events and major bleeding events, the volume of erythrocyte transfusion, the volume of drainage and the duration of drainage after MICS. In addition, the incidence of poor wound healing, the mechanical ventilation time, ICU stay time and postoperative hospitalization time were also documented. Results: There were fewer embolic events (P=1.000) and a higher rate of major bleeding events (P=0.008) in the LMWH group than the Control group, and their magnitude and significance were maintained in the propensity matched analysis. In the matched cohorts, there was no significant difference in the total volume of red blood cell transfusion (P=0.552), assisted mechanical ventilation time (P=0.542), and the ICU stay time (P=0.166) between the two groups; while the volume of drainage (PConclusions: Early prophylactic anticoagulation with LMWH could not reduce the incidence of embolism events after MICS. Instead, it might increase postoperative major bleeding events and prolong drainage tube indwelling time and the length of hospital stay.

A hallmark of type 2 diabetes is impaired insulin receptor (IR) signaling that results in dysregulation of glucose homeostasis. Understanding the molecular origins and progression of diabetes and developing therapeutics depend on experimental models of hyperglycemia, hyperinsulinemia, and insulin resistance. We present a novel monoclonal antibody, IRAB-B, that is a specific, potent IR antagonist that creates rapid and long-lasting insulin resistance. IRAB-B binds to the IR with nanomolar affinity and in the presence of insulin efficiently blocks receptor phosphorylation within minutes and is sustained for at least 3 days in vitro. We further confirm that IRAB-B antagonizes downstream signaling and metabolic function. In mice, a single dose of IRAB-B induces rapid onset of hyperglycemia within 6 h, and severe hyperglycemia persists for 2 weeks. IRAB-B hyperglycemia is normalized in mice treated with exendin-4, suggesting that this model can be effectively treated with a GLP-1 receptor agonist. Finally, a comparison of IRAB-B with the IR antagonist S961 shows distinct antagonism in vitro and in vivo. IRAB-B appears to be a powerful tool to generate both acute and chronic insulin resistance in mammalian models to elucidate diabetic pathogenesis and evaluate therapeutics.

Soft tissue sarcomas (STSs) are a rare and fascinating group of diseases that can be subdivided into specific reciprocal translocations in STSs (SRTSs) and nonspecific reciprocal translocations in STSs (NRTSs). PTEN mutations are rare in STSs, suggesting that PTEN expression may be lost by alternative mechanisms such as methylation. In order to reveal whether aberrant PTEN methylation occurs in STSs, MassARRAY Spectrometry was carried to detect methylation patterns of PTEN in STSs. We evaluated methylation levels in 41 CpG sites from −2,515 to −2,186 bp (amplicon A) and −1,786 to −1,416 bp (amplicon B) relative to the translation initiation site in 110 different cases (46 cases of SRTSs, 40 cases of NRTSs, and 24 cases of normal controls). In addition, immunohistochemistry (IHC) was used to detect the loss of PTEN to determine whether PTEN alterations were responsible for decreased PTEN expression. Our data showed that expression of PTEN was diminished in 49 (57%) STSs, whereas the remaining cases (43%) were classified as high expression. Our previous results found that only 2 of 86 cases (2.3%) had a PTEN mutation suggesting that PTEN may be mainly downregulated in STSs by methylation, but not by mutation of PTEN itself. We observed that amplicon A was hypermethylated in STSs with low PTEN expression, whereas normal controls had low methylation levels (P0.05), nor were there significant differences in the methylation levels in PTEN between SRTS and NRTS cases. The majority of individual CpG units within two amplicons was demonstrated to be hypermethylated. These findings indicate that PTEN hypermethylation is a common event in STSs suggesting that the inactivation of PTEN may be due to hypermethylation in the promoter of PTEN. The aberrant methylation of the CpG sites within PTEN promoter may serve as a potential candidate biomarker for STSs.

Mitochondrion plays the key functions in mammalian cells. It is believed that mitochondrion exerts the common biologic functions in many tissues, but also performs some specific functions correspondent with tissues where it is localized. To identify the tissue-specific mitochondrial proteins, we carried out a systematic survey towards mitochondrial proteins in the tissues of C57BL/6J mouse, such as liver, kidney and heart. The mitochondrial proteins were separated by 2DE and identified by MALDI-TOF/TOF MS. Total of 87 unique proteins were identified as the tissue-specific ones, and some representatives were further verified through ICPL quantification and Western blot. Because these issue-specific proteins are coded from nuclear genes, real-time PCR was employed to examine the mRNA status of six typical genes found in the tissues.With combining of the expression data and the co-localization images obtained from confocal microscope, we came to the conclusion that the tissue-specifically mitochondrial proteins were widely distributed among the mouse tissues. Our investigation, therefore, indeed provides a solid base to further explore the biological significance of the mitochondrial proteins with tissue-orientation.