[Expression of long non-coding RNA linc00467 in childhood acute myeloid leukemia and its role in drug resistance].

OBJECTIVE: To study the expression and function of long non-coding RNA linc00467 in childhood acute myeloid leukemia (AML). METHODS: Bone marrow samples were collected from 5 children with AML who were diagnosed from May 2016 to June 2018. Normal bone marrow samples based on bone marrow examination were collected from 3 children as controls. Quantitative real-time PCR was used to measure the expression of linc00467 in the two groups. A lentivirus system was used to achieve overexpression of linc00467 in AML cells (HL-60) (linc00467 overexpression group), and empty vector expressing green fluorescent protein (GFP) was transfected into AML cells to establish a GFP control group. A lentivirus system was used to insert an interfering sequence into AML cells (sh-linc00467 interfering group), and a random sequence was inserted to establish an sh-NC control group. Cell proliferation and resistance to doxorubicin were observed for all groups. RESULTS: Compared with the normal control group, the children with AML had a significant increase in linc00467 (P=0.018). Overexpression and interference with linc00467 expression had no significant effect on cell proliferation. Compared with the GFP control group, the linc00467 overexpression group had a significant increase in the viability of HL-60 cells at the adriamycin concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 µg/mL (P<0.05). Compared with the sh-NC control group, the sh-linc00467 interfering group had a significant reduction in the viability of HL-60 cells at the adriamycin concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 µg/mL (P<0.05). Compared with the untreated group, the adriamycin treatment group had a significant increase in the expression of linc00467 in HL-60 cells (P<0.05). CONCLUSIONS: This study reveals the biological function of linc00467 to promote the resistance to adriamycin in AML, which provides a basis for developing new therapeutic drugs for AML.

[Current status of vitamin A deficiency in preschool children in Dongguan, China and the effect of vitamin A on serum ferritin and red blood cell parameters].

OBJECTIVE: To investigate the current status of vitamin A deficiency in preschool children in Dongguan, China, as well as the effect of vitamin A on serum ferritin, red blood cell, and reticulocyte parameters. METHODS: Cluster sampling was performed from April 2015 to December 2016 to select 2 085 preschool children (3-6 years old) without any disease in Dongguan. Routine blood test, reticulocyte count, serum ferritin measurement, hemoglobin electrophoresis, and vitamin A measurement were performed for all children. The associations of age and sex with vitamin A and serum ferritin concentrations were analyzed. The effect of vitamin A concentration on serum ferritin, red blood cell, and reticulocyte parameters and the effect of reduced iron storage caused by vitamin A deficiency on red blood cell parameters were evaluated. RESULTS: Of the 2 085 children, 140 (6.71%) had reduced iron storage, and 678 (32.52%) had vitamin A deficiency. Among the 678 children with vitamin A deficiency, 647 (95.4%) had subclinical deficiency and 31 (4.6%) had clinical deficiency. There was no significant difference in vitamin A concentration between boys and girls, however girls had a significantly higher serum ferritin concentration than boys (P<0.05). The clinical vitamin A deficiency group had a significantly higher serum ferritin concentration than the subclinical vitamin A deficiency group and the normal group (P<0.05). In cases of vitamin A deficiency, the reduced iron storage group had significant reductions in mean corpuscular volume and mean corpuscular hemoglobin than the normal iron storage group (P<0.05). Compared with the normal vitamin A group, the vitamin A deficiency group had significantly lower hemoglobin concentration, mean corpuscular hemoglobin, red blood cell count, hematocrit, absolute reticulocyte count, reticulocyte percentage, and reticulocyte hemoglobin content, as well as a significantly higher mean corpuscular volume (P<0.05). CONCLUSIONS: Vitamin A deficiency is prevalent in preschool children in Dongguan, China, and it may adversely affect serum ferritin, red blood cell, and reticulocyte parameters.

Residue depletion of nifuroxazide in broiler chicken.

BACKGROUND: Several nitrofuran drugs have been prohibited for use in food producing animals due to their carcinogenic and mutagenic effects. However, one of the nitrofurans, nifuroxazide, is still used as a veterinary drug in some countries. This study was conducted to investigate the residue depletion of nifuroxazide in broiler chicken. Chickens were fed with dietary feeds containing 50 mg kg⁻¹ of nifuroxazide for seven consecutive days. Liver, kidney, muscle and plasma samples were collected at different withdrawal periods, and the residues of parent nifuroxazide and its acid-hydrolysable side chain, 4-hydroxybenzhydrazide (HBH), in these samples were determined. RESULTS: Nifuroxazide was metabolised in vivo and its metabolite HBH was formed. Parent nifuroxazide was not detectable in these samples after 14 days of cessation. HBH was detectable in these samples even after 28 days of cessation and the total HBH residues were higher than 1.0 ng g⁻¹. Furthermore, the residue level of tissue bound HBH was much higher than that of free HBH. CONCLUSION: The tissue-bound HBH could be used as a marker to monitor the residue of nifuroxazide in chicken and the best target tissue should be liver. This is the first paper reporting the residue depletion of nifuroxazide in chicken.

The functional changes of the perivascular adipose tissue in spontaneously hypertensive rats and the effects of atorvastatin therapy.

The aim of this study was to examine the function of perivascular adiposa tissue (PVAT) on vascular relaxation response in spontaneously hypertensive rats (SHR) and the modulatory effects of the atorvastatin therapy on the PVAT functions. We investigated the mechanisms of the perivascular adipocyte-derived relaxation factor (PVRF) by using isolated rat's aortic rings and isometric contraction measurements. We found that contraction of the thoracic aorta induced by phenylephrine was significantly attenuated in the presence of PVAT from normotensive Wistar-Kyoto rats (WKY group) or the spontaneously hypertensive rats treated with atorvastatin (SHR-A group, atorvastatin 50mg/kg/day), whereas this effect was not observed in the thoracic aortic rings from the control SHR (SHR group). Transferring the solution incubated with PVAT-intact thoracic aorta to PVAT-free thoracic aorta, it induced a remarkable relaxation response in the WKY but not in the control SHR. Tetraethylammoniumchloride (TEA) could block the above relaxation. It was also shown that the PVRF function was likely, depending on the extracellular [Ca(2+)]; the anti-contractile effect of PVAT could be reduced by the inhibitor of the adenosine triphosphate (ATP)-dependent potassium channels, glibenclamide, and could be reduced by the inhibitor of cyclooxygenase by indomethacin. We thus infer that the PVAT function was distorted in hypertension rats, and the lipid-lowering treatment with atorvastatin could restore the PVAT function. The function of the PVRF may involve the Ca(2+)-activated potassium channels, the ATP-dependent potassium channels in vascular smooth muscle cell (SMC), and the release of PVRF from PVAT may involve prostaglandins (PGs) and the calcium metabolism. These results provide an insight into the pathological mechanisms of hypertension development, and indicate that the PVAT may be a potential new target for the hypertensive therapy.