Sphere-forming cell subpopulations with cancer stem cell properties in human hepatoma cell lines

<p>Abstract</p> <p>Background</p> <p>Cancer stem cells (CSCs) are regarded as the cause of tumor formation and recurrence. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs.</p> <p>Methods</p> <p>Human hepatoma cell lines were plated in stem cell conditioned culture system allowed for sphere forming. To evaluate the stemness characteristics of spheres, the self-renewal, proliferation, chemoresistance, tumorigenicity of the PLC/PRF/5 sphere-forming cells, and the expression levels of stem cell related proteins in the PLC/PRF/5 sphere-forming cells were assessed, comparing with the parental cells. The stem cell RT-PCR array was performed to further explore the biological properties of liver CSCs.</p> <p>Results</p> <p>The PLC/PRF/5, MHCC97H and HepG2 cells could form clonal nonadherent 3-D spheres and be serially passaged. The PLC/PRF/5 sphere-forming cells possessed a key criteria that define CSCs: persistent self-renewal, extensive proliferation, drug resistance, overexpression of liver CSCs related proteins (Oct3/4, OV6, EpCAM, CD133 and CD44). Even 500 sphere-forming cells were able to form tumors in NOD/SCID mice, and the tumor initiating capability was not decreased when spheres were passaged. Besides, downstream proteins DTX1 and Ep300 of the CSL (CBF1 in humans, Suppressor of hairless in Drosophila and LAG1 in C. elegans) -independent Notch signaling pathway were highly expressed in the spheres, and a gamma-secretase inhibitor MRK003 could significantly inhibit the sphere formation ability.</p> <p>Conclusions</p> <p>Nonadherent tumor spheres from hepatoma cell lines cultured in stem cell conditioned medium possess liver CSC properties, and the CSL-independent Notch signaling pathway may play a role in liver CSCs.</p

Valuable predictors of gestational diabetes mellitus in infertile Chinese women with polycystic ovary syndrome: a prospective cohort study

Objective: This study aimed to explore valuable preconception predictors of gestational diabetes mellitus (GDM) in PCOS patients.Methods: A prospective cohort study enrolling infertile Chinese PCOS women treated with ovulation induction was performed. The endocrine, metabolic and physical features of all the patients were collected before pregnancy and then followed up to 6 weeks after delivery. The prevalence of GDM was determined during 24–28 gestational weeks. Logistic regression analysis and receiver operating characteristic (ROC) curves were applied to explore the risk factors and their predictive value for GDM.Results: A total of 94 infertile PCOS women who got singleton pregnancy by ovulation induction were enrolled in the study. Logistic regression analysis showed that the preconception insulin under the curve (IAUC) and sex hormone-binding globulin (SHBG) levels were two most significant risk factors for developing GDM (p = 0.014; p = 0.042, respectively). The area of SHBG and IAUC under the ROC curve were 0.806 (p < 0.001) and 0.775 (p = 0.001), respectively. The optimal cutoff values were failed to be calculated because of the limited group size.Conclusions: Low SHBG level and hyperinsulinism were both strongly associated with the development of GDM and might be two valuable predictors in PCOS patients

Interface Characteristics and Mechanical Properties of 2024 Aluminum Alloy and 304 Stainless Steel Dissimilar Alloys FSLW Joint with Ni Interlayer

The composite structure of aluminum and steel (Al/steel) dissimilar metals has been applied in manufacturing industries for lightweight products, and friction stir lap welding (FSLW) has advantages for the welding of these two metals. To further enhance the strength of the Al/steel FSLW joint, a 0.02 mm thick nickel (Ni) foil was chosen as the interlayer, and slight plunging depth of a tool pin into the lower steel sheet was designed, which can respectively change the intermetallic compounds (IMCs) type and produce small welding heat. Choosing dissimilar 2024 aluminum alloy and 304 stainless steel materials as the research subject, the characteristics of the lap interface and the mechanical properties of the joint were mainly discussed. The results showed that the lap interface between the upper aluminum and lower steel sheets was made up of an AlNi3 IMCs layer, hook structure and mechanical occlusion. The AlNi3 IMCs layer with 2 &mu;m thickness was in a reasonable range positive to the joint strength. When the rotating speed of the stirring tool increased from 800 to 1200 rpm and the welding speed of 75 mm/min was constant, the hook structure and the mechanical occlusion were both enhanced, and the tensile shear strength of the joint was decreased. A maximum joint tensile shear strength of 217 MPa was obtained at 800 rpm, and the strength value was 47.2 percent of that of the 2024 aluminum alloy base material. The Al/steel joint with shear fracture mode presented a brittle&ndash;ductile mixed fracture

Interface Characteristics and Mechanical Properties of 2024 Aluminum Alloy and 304 Stainless Steel Dissimilar Alloys FSLW Joint with Ni Interlayer

The composite structure of aluminum and steel (Al/steel) dissimilar metals has been applied in manufacturing industries for lightweight products, and friction stir lap welding (FSLW) has advantages for the welding of these two metals. To further enhance the strength of the Al/steel FSLW joint, a 0.02 mm thick nickel (Ni) foil was chosen as the interlayer, and slight plunging depth of a tool pin into the lower steel sheet was designed, which can respectively change the intermetallic compounds (IMCs) type and produce small welding heat. Choosing dissimilar 2024 aluminum alloy and 304 stainless steel materials as the research subject, the characteristics of the lap interface and the mechanical properties of the joint were mainly discussed. The results showed that the lap interface between the upper aluminum and lower steel sheets was made up of an AlNi3 IMCs layer, hook structure and mechanical occlusion. The AlNi3 IMCs layer with 2 μm thickness was in a reasonable range positive to the joint strength. When the rotating speed of the stirring tool increased from 800 to 1200 rpm and the welding speed of 75 mm/min was constant, the hook structure and the mechanical occlusion were both enhanced, and the tensile shear strength of the joint was decreased. A maximum joint tensile shear strength of 217 MPa was obtained at 800 rpm, and the strength value was 47.2 percent of that of the 2024 aluminum alloy base material. The Al/steel joint with shear fracture mode presented a brittle–ductile mixed fracture

The Impact of Continuous Cropping on Phenolic Acids in Muskmelon Soil and the Colonization of <i>Trichoderma viride</i>

The obstacle associated with continuous cropping is an important problem in the production of muskmelon (Cucumis melo L.). The allelochemicals from root exudates play an active role in root–microbe communication. The primary objective of this study was to delve into the impact of root exudates and the continuous cultivation of muskmelon on the growth and colonization patterns of Trichoderma viride T23. It was observed that the root exudates of muskmelon significantly promoted mycelial growth and the sporulation of Trichoderma viride T23 at concentrations of 0.05, 0.1 g·mL−1, while at a concentration of 0.05 g·mL−1, the enzyme activities of β-glucosidase, chitinase and cellulase were 12.34, 13.23, and 17.85 U·mL−1, respectively, which were higher than those of the control. With increasing concentrations of root exudates, the hyphal growth, spore germination, and the three enzyme activities of Trichoderma viride T23 were decreased. The findings from the pot experiments revealed that the total phenolic acid content in the soil of replanted muskmelon demonstrated a trend of escalating over the course of the first growth cycle of continuous cropping to the fourth growth cycle of continuous cropping. The population density in the rhizosphere soil of Trichoderma viride T23 in the first growth cycle and the second growth cycle of continuous cropping shows a significant difference compared with other treatments, which led to statistically significant increments of stem diameter, leaf area, fresh weight, dry weight and SPAD index. It is necessary to increase the dose of the beneficial microorganism or degrade the phenolics in the rhizosphere soil to promote effectiveness while increasing the growth cycles of continuous cropping

Chronic Prenatal Hypoxia Down-Regulated BK Channel Β1 Subunits in Mesenteric Artery Smooth Muscle Cells of the Offspring

Background/Aims: Chronic hypoxia in utero could impair vascular functions in the offspring, underlying mechanisms are unclear. This study investigated functional alteration in large-conductance Ca2+-activated K+ (BK) channels in offspring mesenteric arteries following prenatal hypoxia. Methods: Pregnant rats were exposed to normoxic control (21% O2, Con) or hypoxic (10.5% O2, Hy) conditions from gestational day 5 to 21, their 7-month-old adult male offspring were tested for blood pressure, vascular BK channel functions and expression using patch clamp and wire myograh technique, western blotting, and qRT-PCR. Results: Prenatal hypoxia increased pressor responses and vasoconstrictions to phenylephrine in the offspring. Whole-cell currents density of BK channels and amplitude of spontaneous transient outward currents (STOCs), not the frequency, were significantly reduced in Hy vascular myocytes. The sensitivity of BK channels to voltage, Ca2+, and tamoxifen were reduced in Hy myocytes, whereas the number of channels per patch and the single-channel conductance were unchanged. Prenatal hypoxia impaired NS1102- and tamoxifen-mediated relaxation in mesenteric arteries precontracted with phenylephrine in the presence of Nω-nitro-L-arginine methyl ester. The mRNA and protein expression of BK channel β1, not the α-subunit, was decreased in Hy mesenteric arteries. Conclusions: Impaired BK channel β1-subunits in vascular smooth muscle cells contributed to vascular dysfunction in the offspring exposed to prenatal hypoxia