The laminin subunit alpha 2 (LAMA2) gene encodes an alpha 2 chain, which constitutes one of the subunits of laminin 2 (merosin) and laminin 4 (s-merosin). In the current study, we investigated the ...relationship between LAMA2 promoter methylation status and the invasiveness of clinically nonfunctioning pituitary adenomas (PitNETs). Specimens from patients with nonfunctioning PitNET were classified into three groups according to preoperative computed tomography (CT)/magnetic resonance imaging findings: a normal group (n = 6), non-invasive group (n = 11) and invasive group (n = 6). LAMA2 expression was assessed using quantitative real-time polymerase chain reaction (RT-qPCR) and western blotting, and the methylation status of the LAMA2 promoter region was observed using sodium bisulfite sequencing. Furthermore, 5-aza-2-deoxycytidine was used to explore the relationship between decreased LAMA expression and methylation in PitNET cells. According to the RT-qPCR and western blotting results, LAMA2 expression was downregulated in invasive PitNET, while the methylation of the LAMA2 promoter was increased. Methylation of the LAMA2 promoter decreased the expression of LAMA2. Thus, changes in LAMA2 expression due to promoter methylation were inversely correlated with the invasiveness of PitNET and the protein functions as a tumor suppressor. In addition, overexpression and demethylation of LAMA2 suppressed the invasion of PitNET cells, partially by exerting effects on the PTEN-PI3K/AKT signaling pathway and matrix metalloproteinase-9 (MMP-9). Furthermore, a xenograft model was also generated, and LAMA2 overexpression significantly suppressed tumor growth in vivo. Thus, LAMA2 expression and methylation patterns might be used as biomarkers to predict the prognosis of patients with PitNET.
Previous studies indicated that fruit bats carry two betacoronaviruses, BatCoV HKU9 and BatCoV GCCDC1. To investigate the epidemiology and genetic diversity of these coronaviruses, we conducted a ...longitudinal surveillance in fruit bats in Yunnan province, China during 2009–2016. A total of 59 (10.63%) bat samples were positive for the two betacorona-viruses, 46 (8.29%) for HKU9 and 13 (2.34%) for GCCDC1, or closely related viruses. We identified a novel HKU9 strain, tentatively designated as BatCoV HKU9-2202, by sequencing the full-length genome. The BatCoV HKU9-2202 shared 83% nucleotide identity with other BatCoV HKU9 stains based on whole genome sequences. The most divergent region is in the spike protein, which only shares 68% amino acid identity with BatCoV HKU9. Quantitative PCR revealed that the intestine was the primary infection organ of BatCoV HKU9 and GCCDC1, but some HKU9 was also detected in the heart, kidney, and lung tissues of bats. This study highlights the importance of virus surveillance in natural reservoirs and emphasizes the need for preparedness against the potential spill-over of these viruses to local residents living near bat caves.
The acaricidal activity of Adonis coerulea extracts was investigated against Psoroptes cuniculi. The aqueous, methanol, acetic ether and petroleum ether extracts all showed marked acaricidal activity ...in vitro. Especially, the acetic ether extract possessed strong toxicity against mites in vitro with LT50 values 0.743h, 2.730h, 5.919h and 22.536h at concentrations of 500, 250, 125 and 62.5mg/ml, respectively. At the same time, the acetic ether extract showed the best effectiveness topically to infested rabbits in vivo. After three times treatment, at the day 20, rabbits treated with A. coerulea extract were observed only small scabs or secretions in ear canal, but no mites. These findings suggested that as a potential insecticide, A. coerulea should be studied further to develop active components or a new acaricidal drug.
Background:
Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are effective procedures for the treatment of vertebral compression fractures (VCFs). However, recent studies have ...reported that secondary VCFs develop in patients after PVP or PKP treatment. This study aimed to investigate the clinical characteristics and management of secondary fractures after PVP or PKP.
Materials and Methods:
599 cases who had vertebral compression fracture and underwent PVP or PKP between September 2008 and June 2014 were enrolled, including 121 males and 478 females. Secondary fractures were observed in 52 cases, including 3 males and 49 females, who were treated by re-operation with PVP or PKP.
Results:
The ratio of secondary fracture after PVP or PKP was 8.68% in all cases. The age ranged from 59 to 92 years (74.41 ± 6.83 average). A composition of 44.44% of the secondary fracture occurred near the initial fracture vertebrae. After re-operation with PVP or PKP, visual analog scale score significantly decreased to 2.72 ± 0.88 or 2.52 ± 1.12, respectively, anterior height of vertebral bodies increased to 24.69 ± 4.59 or 24.54 ± 5.97 mm, respectively, and middle height of vertebral bodies increased to 20.90 ± 3.72 or 20.36 ± 6.33 mm, respectively.
Conclusions:
There is a high chance of secondary fracture near the initially operated vertebrae after PVP or PKP. Re-operation with PVP or PKP achieves satisfactory outcomes in these patients such as pain relief and the recovery of the vertebrae height.
Objectives The present study aimed to investigate whether salidroside can induce differentiation of rat mesenchymal stem cells (rMSCs) towards hepatocytes in vitro and the mechanism of hepatic ...differentiation of rMSCs.
Methods rMSCs were subject to hepatic differentiation. One, two and three weeks later, the expression of alpha fetoprotein (AFP) and albumin (ALB), cytochrome P450 (CYP450)‐dependent activity and inducibility, cellular uptake of low density lipoprotein (LDL) and urea synthesis were assessed and the hepatic differentiation of rMSCs was evaluated. In order to unravel the mechanism of hepatic differentiation of rMSCs in vitro, inhibitors of extracellular regulated kinase1/2 (ERK1/2), phosphatidylinositol 3‐kinase (PI3K) and p38 were applied. When the process of hepatic differentiation was completed, special proteins of hepatic differentiation were detected and blocking of inhibitors was evaluated.
Key findings Salidroside significantly induce differentiation of rMSCs towards hepatocytes. Differentiated rMSCs have typical functional hepatic characteristics. The results also showed that the ERK1/2 and PI3K signalling pathways play important roles in the regulatory effects of salidroside on hepatic differentiation of rMSCs and are involved in cell fate determinations, while the p38 signalling pathway does not.
Conclusions Salidroside can induce differentiation of rMSCs towards hepatocytes in vivo, and the ERK1/2 or PI3K signalling pathway underlie the process of hepatic differentiation.
The effect of surface roughness on the oxidation behavior of a directionally solidified Ni-based superalloy was investigated by surface mapping microscope, scanning electron microscope and X-ray ...diffraction. It was found that specimens with surface roughness of 0.05 µm exhibit the best oxidation resistance, while specimens with surface roughness of 0.14 µm behave worse than specimens with surface roughness of 0.83 µm. The specimens with surface roughness of 0.05 µm have the best oxidation resistance, which is mainly due to the smallest surface area exposed in air and thinnest work-hardening layer. The Al
2
O
3
layer alleviates the oxidation process of the specimens with surface roughness of 0.83 µm, and this is the possible reason for the better oxidation resistance of samples with surface roughness of 0.83 µm than samples with surface roughness of 0.14 µm.
To investigate the oxidation behavior of a nickel-based superalloy with high hafnium content (1.34wt%), this study performed isothermal oxidation tests at 900, 1000, and 1100°C for up to 200 h. X-ray ...diffraction and scanning electron microscopy with energy-dispersive X-ray spectroscopy were applied to study the oxidation behavior. The weight gain of the high Hf nickel-based superalloy exhibited a parabolalike curve, and no spallation of the oxide scale was observed during the oxidation tests. The alloy presented excellent oxidation resistance, and no HfO
2
was observed in the oxide scale at 900°C. With the increase of the oxidation temperature to 1000°C, HfO
2
particles formed in the spinel phases of the scale, and “peg-like” HfO
2
was observed within and beneath the inner layer of Al
2
O
3
after 200 h. As the oxidation temperature rose to 1100°C, “peg-like” HfO
2
was observed at the early stage of the oxidation test (within 25 h). The formation mechanism of HfO
2
and its impact on oxidation resistance were investigated based on the analysis of the oxidation test results at different temperatures.
The purpose of this investigation is to understand flow characteristics in
mini/micro sonic nozzles, in order to precisely measure and control miniscule
flowrates. Experimental and numerical ...simulation methods have been used to
study critical flow Venturi nozzles. The results show that the nozzle?s size
and shape influence gas flow characteristics which leading the boundary layer
thickness to change, and then impact on the discharge coefficient. With the
diameter of sonic nozzle throat decreasing, the discharge coefficient
reduces. The maximum discharge coefficient exits in the condition of the
inlet surface radius being double the throat diameter. The longer the
diffuser section, the smaller the discharge coefficient becomes. Diffuser
angle affects the discharge coefficient slightly.
nema
A direct insulator-quantum Hall (I-QH) transition corresponds to a crossover/transition from the insulating regime to a high Landau level filling factor ν > 2 QH state. Such a transition has been ...attracting a great deal of both experimental and theoretical interests. In this study, we present three different two-dimensional electron systems (2DESs) which are in the vicinity of nanoscaled scatterers. All these three devices exhibit a direct I-QH transition, and the transport properties under different nanaoscaled scatterers are discussed.
The microstructure and stress-rupture property of the large-scale complex single crystal (SX) casting DD10 were investigated in high-rate solidification process. It is found that the primary dendrite ...arm spacing (PDAS) does not increase monotonically with the height increase. When across the platform, the temperature gradient increases due to the effect of platform, and the corresponding PDAS decreases. The distribution of eutectic volume fraction in large-scale complex SX casting is affected by PDAS, solid back diffusion, and the development of high order dendrites. The eutectic volume fraction contained in the sample taken below the platform decreases with the height increase. While the eutectic volume fraction contained in the sample taken upper the platform increases gradually with the height increase. After heat treatment, most of the
γ
/
γ′
eutectics are eliminated and the components are distributed uniformly. The similar stress rupture properties of the samples at different heights in the same direction are obtained.
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