Enhanced cardiac expression of two isoforms of matrix metalloproteinase-2 in experimental diabetes mellitus.

BackgroundDiabetic cardiomyopathy (DM CMP) is defined as cardiomyocyte damage and ventricular dysfunction directly associated with diabetes independent of concomitant coronary artery disease or hypertension. Matrix metalloproteinases (MMPs), especially MMP-2, have been reported to underlie the pathogenesis of DM CMP by increasing extracellular collagen content.PurposeWe hypothesized that two discrete MMP-2 isoforms (full length MMP-2, FL-MMP-2; N-terminal truncated MMP-2, NTT-MMP-2) are induced by high glucose stimulation in vitro and in an experimental diabetic heart model.MethodsRat cardiomyoblasts (H9C2 cells) were examined to determine whether high glucose can induce the expression of the two isoforms of MMP-2. For the in vivo study, we used the streptozotocin-induced DM mouse heart model and age-matched controls. The changes of each MMP-2 isoform expression in the diabetic mice hearts were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemical stains were conducted to identify the location and patterns of MMP-2 isoform expression. Echocardiography was performed to compare and analyze the changes in cardiac function induced by diabetes.ResultsQuantitative RT-PCR and immunofluorescence staining showed that the two MMP-2 isoforms were strongly induced by high glucose stimulation in H9C2 cells. Although no definite histologic features of diabetic cardiomyopathy were observed in diabetic mice hearts, left ventricular systolic dysfunction was determined by echocardiography. Quantitative RT-PCR and IHC staining showed this abnormal cardiac function was accompanied with the increases in the mRNA levels of the two isoforms of MMP-2 and related to intracellular localization.ConclusionTwo isoforms of MMP-2 were induced by high glucose stimulation in vitro and in a Type 1 DM mouse heart model. Further study is required to examine the role of these isoforms in DM CMP

Selective autophagy in the Hepatitis C Virus NS5A degradation

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Interferon-inducible proteoglycan in the regulation of virus infection

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Elasto-inertial microfluidic separation of microspheres with submicron resolution at high-throughput

Abstract Elasto-inertial microfluidic separation offers many advantages including high throughput and separation resolution. Even though the separation efficiency highly depends on precise control of the flow conditions, no concrete guidelines have been reported yet in elasto-inertial microfluidics. Here, we propose a dimensionless analysis for precise estimation of the microsphere behaviors across the interface of Newtonian and viscoelastic fluids. Reynolds number, modified Weissenberg number, and modified elastic number are used to investigate the balance between inertial and elastic lift forces. Based on the findings, we introduce a new dimensionless number defined as the width of the Newtonian fluid stream divided by microsphere diameter. The proposed dimensionless analysis allows us to predict whether the microspheres migrate across the co-flow interface. The theoretical estimation is found to be in good agreement with the experimental results using 2.1- and 3.2-μm-diameter polystyrene microspheres in a co-flow of water and polyethylene oxide solution. Based on the theoretical estimation, we also realize submicron separation of the microspheres with 2.1 and 2.5 μm in diameter at high throughput, high purity (>95%), and high recovery rate (>97%). The applicability of the proposed method was validated by separation of platelets from similar-sized Escherichia coli (E.coli)

The association of maternal serum biomarkers and birth weight in twin pregnancy: a retrospective cohort study

We retrospectively reviewed the medical records of 524 women with twin pregnancies who underwent antenatal care and gave birth in the past 12 years. Birth weight (BW) data were classified into three groups. We analysed the association between maternal serum biomarkers and BW in twin pregnancies using multiple logistic regression analysis. There were significant differences in the MoM values of pregnancy-associated plasma protein-A (PAPP-A), unconjugated oestriol (uE3) and inhibin A between low BW and healthy newborns. The inhibin A value was significantly higher in women with small-for-gestational-age (SGA) foetuses and the PAPP-A, and uE3 values were lower in the SGA group than in the other groups using the generalised linear mixed model (hierarchical modelling considering cluster effects for twins). Maternal serum biomarkers, including PAPP-A, uE3, and inhibin A, may be associated with SGA in twin pregnancy. Our results might provide useful information for SGA prediction during prenatal period in twin pregnancy. IMPACT STATEMENT What is already known on this subject? The SGA is more frequent in twin pregnancies than in singleton, but there is no clearly identification of the aetiology of SGA. Further, most studies have been conducted in singleton pregnancies. What do the results of this study add? The association of each maternal serum marker with SGA was assessed in the current study, and it is demonstrated that the levels of PAPP-A and uE3 in maternal serum of SGA foetuses were significantly lower than those in the other groups. In contrast, the levels of inhibin A were significantly increased in the SGA. What are the implications of these findings for clinical practice and/or further research? The maternal serum biomarker of inhibin A was a more valuable predictive factor for SGA prediction in twins. The results of this study can be used in counselling prenatal screening. Further prospective research is needed to combine with ultrasound growth parameters, which can be generalised for the prediction of SGA in twins

Insights into structural defect formation in individual InP/ZnSe/ZnS quantum dots under UV oxidation

Abstract InP/ZnSe/ZnS quantum dots (QDs) stand as promising candidates for advancing QD-organic light-emitting diodes (QLED), but low emission efficiency due to their susceptibility to oxidation impedes applications. Structural defects play important roles in the emission efficiency degradation of QDs, but the formation mechanism of defects in oxidized QDs has been less investigated. Here, we investigated the impact of diverse structural defects formation on individual QDs and propagation during UV-facilitated oxidation using high-resolution (scanning) transmission electron microscopy. UV-facilitated oxidation of the QDs alters shell morphology by the formation of surface oxides, leaving ZnSe surfaces poorly passivated. Further oxidation leads to the formation of structural defects, such as dislocations, and induces strain at the oxide-QD interfaces, facilitating In diffusion from the QD core. These changes in the QD structures result in emission quenching. This study provides insight into the formation of structural defects through photo-oxidation, and their effects on emission properties of QDs