Differential expression of DKK-1 binding receptors on stromal cells and myeloma cells results in their distinct response to secreted DKK-1 in myeloma

<p>Abstract</p> <p>Background</p> <p>The canonical Wnt signaling is concurrently important for osteoblast differentiation and myeloma cell proliferation. Its activation in myeloma cells and its inhibition in osteoblasts and their progenitors have been identified in the previous studies. Osteoblast progenitors and myeloma cells from a myeloma patient share the same bone marrow (BM) microenvironment, but respond differently to DKK-1 secreted by myeloma cells. The mechanisms remain unclear.</p> <p>Methods</p> <p>Primary multiple myeloma (MM) cells were isolated from BM mononuclear cells of 12 MM patients. Human bone marrow stromal cells (SCs) were obtained from BM adherent cells of these MM patients and 10 healthy donors. The mRNA expression levels of DKK-1 binding receptor LRP5/6 and Kremen1/2 (Krm1/2) were analyzed by Real-time PCR in human myeloma cell line (HMCL) RPMI-8226, NCI-H929, U266, LP-1, CZ-1, KM-3, Sko-007, primary myeloma cells and SCs from 12 MM patients and SCs from 10 healthy donors. The binding capability of DKK-1 binding receptors to DKK-1 on primary myeloma cells and SCs was detected by flow cytometry assay.</p> <p>Results</p> <p>The mRNA expression levels of DKK-1 binding receptor LRP5/6 and Krm1/2 in SCs from patients with MM were significantly higher than those in myeloma cells and in SCs from healthy donors. The binding capability to DKK-1of DKK-1 binding receptors on SCs from MM patients was obviously higher than those on myeloma cells and SCs from healthy donors by flow cytometry assay. Similar to the effects of coculture with rhDKK1, coculture of SCs from healthy donors with myeloma cells in the presence or absence of a Transwell insert did up-regulate SCs' mRNA levels of LRP5/6 and Krm1/2, and down-regulate their mRNA levels of β-catenin.</p> <p>Conclusion</p> <p>Compared with myeloma cells, the SCs from MM patients overexpress DKK-1 binding receptors LRP5/6 and Krm1/2 in response to DKK-1 secreted by myeloma cells, which results in intracellular Wnt signaling inhibition. Our study provides a novel insight into mechanisms of myeloma associated osteolytic lesions.</p

Research Progress on Reference Genes of Insect for Quantitative Real-time Reverse Transcription PCR (RT-qPCR)

Abstract Quantitative real-time reverse transcription PCR (RT-qPCR) has become the most important method for the quantification of mRNA transcription levels owing to its, specificity, sensitivity, reproducibility, and efficiency. In order to avoid sample-to-sample and run-to-run variations particularly in RNA extraction, RNA quality and cDNA reverse transcription level ,etc. it is necessary to use housekeeping gene which stably expressing as reference gene. Ideally, the housekeeping gene should not be regulated or influenced by the experimental procedure or co-regulated with the target gene. Studies insect models have shown that the expression levels of commonly used reference genes can differ among different tissue, organ types or physiological conditions. However, improper selection of reference genes will result in inaccurate calculation results and consequently obscure actual biological differences among samples, even opposite conclusion. Therefore, reference genes which specific stably expression in each experimental system should be selected in different insects and different experiments. This review aims to provide research achievements of domestic and foreign scholars on insect reference genes, which provide great promise for the future

4-Benz­yloxy-2-bromo-1-meth­oxy­benzene

In the title compound, C14H13BrO2, the phenyl ring is oriented at a dihedral angle of 72.6 (3)° with respect to the bromo­meth­oxy­phenyl ring. The crystal structure is stabilized by weak inter­molecular C—H⋯O inter­actions

Mediastinal Lymph Node Metastases in Thyroid Cancer: Characteristics, Predictive Factors, and Prognosis

Background. Mediastinal lymph node metastases (MLNM) have not been extensively studied. The aim of this study is to investigate the characteristics, predictive factors, and prognosis of MLNM in thyroid cancer. Methods. This is a retrospective study based on the thyroid cancer patients with MLNM at our institution from 2008 to 2015. Results. In total, 73 thyroid cancer patients with positive MLNM were included in this study. It contained sixty patients (82.2%) with papillary thyroid carcinoma (PTC), twelve (16.4%) with medullary thyroid carcinoma, and one (1.4%) with anaplastic thyroid carcinoma. Forty-eight patients had the surgery as initial treatment. Fifty-three (72.6%) patients remained disease-free, and fifteen (20.5%) developed a regional recurrence. Distant metastases occurred in four (5.5%) patients and five (6.8%) patients died. Five-year overall survival rate and disease-free survival (DFS) rate of the PTC patients for initial treatment are 95.4% and 77.2%, respectively. Extrathyroidal extension and multiple lymph nodes involved were associated with DFS in PTC patients. Conclusions. Initial therapeutic control is very important for the thyroid cancer patients. Extrathyroidal extension and multiple mediastinal lymph nodes involved were the influence factors of prognosis in the thyroid cancer patients with MLNM

Electroacupuncture Ameliorates Acute Lung Injury through Promoting Gastrointestinal Motility in Rats with Acute Pancreatitis

Objective. Gastrointestinal disfunction and acute lung injury (ALI) were common in acute pancreatitis (AP). The effect of electro-acupuncture (EA) on gastrointestinal motility and ALI in rats with AP was investigated to verify the theory of “lung and large intestine are interior exteriorly related” in traditional Chinese medicine. Methods. Male Sprague-Dawley rats were randomly divided into the normal group, model group, and EA group. AP model was established by three injections of 20% L-arginine at 1 h intervals. EA were applied to bilateral ST-25 and ST-36 for 30 minutes twice a day after modeling for 3 days. Arterial blood, pancreas, lung, and intestinal tissues were collected for detecting the inflammatory factors and histopathology. Intestinal propulsion rate (IPR) was also measured at 72 h. Results. EA treatment improved IPR and increased CCK-8 level compared with model group (P < 0.05). It lowered the serum levels of TNF-α and IL-6 and increased the level of IL-4 with no effect on IL-10. EA treatment reduced serum vasoactive intestinal peptide (VIP) and myeloperoxidase (MPO) level in the lung and the pathologic scores of pancreas, lung and intestine were decreased (P < 0.05). Conclusion. EA treatment could promote gastrointestinal motility through inhibiting VIP, and promoting CCK expression and regulate pro- and anti-inflammatory mediators to ameliorate ALI in AP

A New Model of Stopping Sight Distance of Curve Braking Based on Vehicle Dynamics

Compared with straight-line braking, cornering brake has longer braking distance and poorer stability. Therefore, drivers are more prone to making mistakes. The braking process and the dynamics of vehicles in emergency situations on curves were analyzed. A biaxial four-wheel vehicle was simplified to a single model. Considering the braking process, dynamics, force distribution, and stability, a stopping sight distance of the curve braking calculation model was built. Then a driver-vehicle-road simulation platform was built using multibody dynamic software. The vehicle test of brake-in-turn was realized in this platform. The comparison of experimental and calculated values verified the reliability of the computational model. Eventually, the experimental values and calculated values were compared with the stopping sight distance recommended by the Highway Route Design Specification (JTGD20-2006); the current specification of stopping sight distance does not apply to cornering brake sight distance requirements. In this paper, the general values and limits of the curve stopping sight distance are presented