Protective effects of villi mesenchymal stem cells on human umbilical vein endothelial cells by inducing SPOCD1 expression in cases of gestational diabetes mellitus.

BACKGROUND: Gestational diabetes mellitus (GDM) is characterized by a lack of response to insulin in pregnancies, and often accompanied by severe complications. GDM is associated with structural and functional alterations, particularly endothelial dysfunction, in various tissues. This study is aimed to investigate the effect of placental mesenchymal stem cells (MSCs) on the endothelial biological function of human umbilical vein endothelial cells (HUVECs) and their molecular mechanisms. METHODS: Villi mesenchymal stem cells (VMSCs) were co-cultured with HUVECs, and transcriptomic analysis of differential genes was performed in HUVECs under high-glucose induction. Lentiviral transfection was performed to construct HUVECs with stable knockdown or overexpression of SPOCD1. The immunohistochemical assays were used to detect the expression of SPOCD1 in GDM patients. TUNEL fluorescence staining was applied for detection of the HUVEC apoptosis. ß galactosidase staining assay was performed to detect the cell senescence. Electron microscopy was used to detect the cell pyroptosis. qRT-PCR and western blot assays were conducted for identifying the mRNA & protein expressions of genes. RESULTS: VMSCs, when co-cultured with HUVECs, could inhibit the apoptosis, pyroptosis and senescence induced by high-glucose condition in HUVECs. Transcriptomic results showed an upregulation of SPOCD1 expression induced by VMSCs in HUVECs. Overexpression of SPOCD1 inhibited high-level glucose-induced apoptosis, pyroptosis and senescence in HUVECs via the ß-catenin pathway. CONCLUSION: VMSCs induce ß-catenin activation by upregulating the expression of SPOCD1 in HUVECs, which ultimately inhibits high-level glucose-induced apoptosis, pyroptosis and senescence in HUVECs. This observation provides potential therapeutic insight for future GDM treatment.

Regulation of Bacterial Biofilm Formation by Ultrasound: Role of Autoinducer-2 and Finite-Element Analysis of Acoustic Streaming.

OBJECTIVE: The formation of bacterial biofilm regulated by quorum sensing (QS) is a critical factor that contributes to infections of indwelling medical devices. Autoinducer-2 (AI-2), as a signal molecule in QS, plays a crucial role in mediating bacterial signaling and regulating their biological behavior. This study investigated the impact of ultrasonic vibration at varying frequencies on biofilm formation in a mixture of Staphylococcus aureus and Escherichia coli. METHODS: By exciting ultrasound at different frequencies (20, 100 and 200 kHz), a vibration with an amplitude of 100 nm was generated on the material surface located at the bottom of the petri dish containing mixed bacteria. We measured the content of AI-2 and bacteria in the mixed bacterial solution and bioburden on material surfaces at different time points during culture. In addition, the relationships among AI-2 content, bacterial concentration and distribution were assessed through finite-element analysis of acoustic streaming under ultrasonic vibration. RESULTS: The AI-2 gradient is influenced by the diversity of acoustic streaming patterns on the material surface and in the mixed bacterial solution caused by ultrasonic vibration at different frequencies, thereby regulating biofilm formation. The experimental results showed that the optimal inhibition effect on AI-2 and minimal bacterial adhesion degree was achieved when applying an ultrasonic frequency of 100 kHz with a power intensity of 46.1 mW/cm2 under an amplitude of 100 nm. CONCLUSION: Ultrasound can affect the QS system of bacteria, leading to alterations in their biological behavior. Different species of bacteria exhibit varying degrees of chemotaxis toward different frequencies.

Graphite Nanoflake-Modified Mo2C with Ameliorated Interfacial Interaction as an Electrocatalyst for Hydrogen Evolution Reaction.

Molybdenum carbide (Mo2C) is anticipated to be a promising electrocatalyst for electrocatalytic hydrogen production due to its low cost, resourceful property, prominent stability, and Pt-like electrocatalytic activity. The rational design of Mo2C-based electrocatalysts is expected to improve hydrogen evolution reaction (HER) performance, especially by constructing ultrasmall Mo2C particles and appropriate interfaces. Herein, composites of molybdenum carbide (Mo2C) quantum dots anchored on graphite nanoflakes (Mo2C/G) were fabricated, which realized a stable overpotential of 136 mV at 10 mA cm-2 for the HER with a small Tafel slope of 76.81 mV dec-1 in alkaline media, and operated stably over 10 h and 2000 cycles. The superior HER performance can be attributed to the fact that graphite nanoflakes could act as a matrix to disperse Mo2C as quantum dots to expose more active sites and guarantee high electronic conductivity and, more importantly, provide ameliorated interfacial interaction between Mo2C and graphite nanoflakes with appropriate hydrogen binding energy and charge density distribution. To further explore which kind of interfacial interaction is more favorable to improve the HER performance, density functional theory calculations and corresponding contrast experiments were also performed, and it was interesting to prove that Mo2C quantum dots anchored to the basal planes of defective graphite nanoflakes exhibit better electrochemical performance than those anchored on the edges.

Strong variation in frequencies of male and female determiners between neighboring housefly populations.

Sex-determination mechanisms evolve rapidly and vary between species. Occasionally, polymorphic systems are found, like in the housefly. Studying the dynamics and stability of such systems can provide a better understanding of the evolution of sex-determination systems. In the housefly, dominant male-determining loci (M) can lie not only on the Y chromosome (MY ), but also on autosomes (MA ) or the X chromosome (MX ). M enforces male development by inhibiting the female-determining gene transformer (tra). A mutant tra allele, traD , is insensitive to M and is a dominant female determiner. MY prevails at high latitudes and polymorphic M loci together with traD at low latitudes. To get more insight into the stability and frequencies of these sex determiners with mutually exclusive dominance, we investigated 5 regional Spanish populations. We found strong variation among populations. Two populations with hemizygous MIII were found, 2 contained homozygous MX with additional hemizygous MI and MII in 1 population. One population contained homozygous and hemizygous MX with additionally hemizygous MII . All females in populations with homozygous M, had traD , whereas no traD was found in populations without homozygous M. Our results indicate locally stable systems may either harbor a single hemizygous M and no traD , corresponding to a male heterogametic system, or homozygous and/or multiple M and heterozygous traD , reminiscent of a female heterogametic system. They support that M loci can accumulate in the presence of a dominant female determiner. Limited migration between populations may contribute to the stability of these systems.

Expression patterns, mutation detection and RNA interference of Rhopalosiphum padi voltage-gated sodium channel genes.

The voltage-gated sodium channel (VGSC) is the target of sodium-channel-blocking insecticides. Traditionally, animals were thought to have only one VGSC gene comprising a α-subunit with four homologous domains (DI-DIV). The present study showed that Rhopalosiphum padi, an economically important crop pest, owned a unique heterodimeric VGSC (H1 and H2 subunits) encoded by two genes (Rpvgsc1 and Rpvgsc2), which is unusual in insects and other animals. The open reading frame (ORF) of Rpvgsc1 consisted 1150 amino acids, and the ORF of Rpvgsc2 had 957 amino acids. Rpvgsc1 showed 64.1% amino acid identity to DI-DII of Drosophila melanogaster VGSC and Rpvgsc2 showed 64.0% amino acid identity to DIII-DIV of D. melanogaster VGSC. A M918L mutation previously reported in pyrethroids-resistant strains of other insects was found in the IIS4-S6 region of R. padi field sample. The two R. padi VGSC genes were expressed at all developmental stages and showed similar expression patterns after treatment with beta-cypermethrin. Knockdown of Rpvgsc1 or Rpvgsc2 caused significant reduction in mortality rate of R. padi after exposure to beta-cypermethrin. These findings suggest that the two R. padi VGSC genes are both functional genes.

Association between serum leptin and adiponectin levels with risk of insulin resistance and impaired glucose tolerance in non-diabetic women.

Obesity is a well known risk factor for insulin resistance and type 2 diabetes. Recently discovered adipocyte-derived proteins (leptin and adiponectin) might contribute to the pathologic mechanism linking obesity and insulin resistance. A total of 190 non-diabetic women were recruited from the Obesity Clinic of Kaohsiung Municipal Hsiao-Kang Hospital, Taiwan, between February 2003 and February 2004. All participants completed a simple questionnaire. Blood pressure and body mass index were measured; blood samples for fasting glucose, total cholesterol, high-density lipoprotein cholesterol, triglyceride, leptin, adiponectin, and fasting insulin level were collected after an overnight fast. Two-hour glucose level after a 75-g glucose tolerance test was determined. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated as the index of insulin resistance. Multivariate linear regression analyses were used to analyze the relationship between adipocytokines and insulin resistance after adjusting for possible confounding factors. Leptin and adiponectin were found to be independently associated with HOMA-IR and fasting insulin concentration, but in divergent directions, after adjusting for potential confounding factors. Adiponectin, but not leptin, was associated with impaired glucose tolerance after adjusting for potential confounding factors. The results suggest that leptin and adiponectin may be involved in the pathophysiologic link between obesity and insulin resistance independently. Low levels of adiponectin may increase the risks of developing impaired glucose metabolism and type 2 diabetes.