Effect of Ecklonia kurome extract on thyroid hormone disorder in rats

Purpose: To investigate the effect of Ecklonia kurome extract (EKE) on thyroid hormone concentrations in male mice.Methods: Mice were administered EKE by gastric intubation for 15 days. PTU or L-T4 was set as positive control. Twenty-four hours after the last administration, all animals were sacrificed by cervical dislocation. Blood was collected and serum samples assayed for T3 and T4. Furthermore, the liver was removed for biochemical analysis.Results: T3 and T4 serum levels in mice decreased after the administration of EKE. The relative potency of EKE was calculated in terms of percent increase or decrease in thyroid hormones. Compared with the control value, the decrease in T3  concentration by a high dose of EKE was approximately 64.32 %. Compared with the control group, hepatic LPO decreased (p < 0.01) while superoxide dismutase (SOD, p < 0.01) and catalase (CAT, p < 0.01) activities were significantly increased by the high dose of EKE, thus indicating its anti-peroxidative role.Conclusion: This suggests that EKE may be useful for the treatment of  hyperthyroidism, but further studies are required to ascertain this.Keywords: Ecklonia kurome, Thyroid hormone, Anti-peroxidative, Hyperthyroidis

The stochastic lot-sizing problem with quantity discounts

This paper addresses the stochastic lot-sizing problem with quantity discounts. In particular, we examine the uncapacitated finite-period economic lot-sizing problem in which the parameters in each period are random and discrete. When an order is placed, a fixed cost is incurred and an all-unit quantity discount is awarded based on the quantity ordered. The lead time is zero and the order is delivered immediately. First we study the case with overstocks by which the excess inventory incurs a holding cost. The objective in this case is to minimize the expected total cost including ordering and holding costs. The stochastic dynamics is modeled with a scenario tree. We characterize properties of the optimal policy and propose a polynomial time algorithm with complexity O ( n 3 ) for single discount level, where n is the number of nodes in the scenario tree. We extend the results to cases allowing stockout and multi-discount levels. Numerical experiments are conducted to evaluate the performance of the algorithm and to gain the man- agement insights

Correlation of survivin, p53 and Ki-67 in laryngeal cancer Hep-2 cell proliferation and invasion

AbstractObjectiveTo investigate the mechanism of survivin, p53 and Ki-67 on Hep-2 human laryngeal cancer endothelial cell proliferation and invasion.MethodsLaryngeal squamous cell carcinoma and paracancerous normal tissues were collected, total RNA was extracted from tissues, survivin, p53 and Ki-67 gene mRNA expression levels in laryngeal cancer and the adjacent tissues were detected by Real-time PCR. Human laryngeal cancer Hep-2 epithelial cells were selected, survivin gene was overexpressed, and cell proliferation was detected by MTT. p53 and Ki-67 gene expression changes in overexpressed survivin gene were detected by Western blot. Changes in Hep-2 cell invasive ability were studied when survivin was overexpressed as detected by Transwell invasion assay.ResultsIn the adjacent tissues, survivin, p53 and Ki-67 gene relative expression levels were 1.72 ± 0.9, 13.7 ± 5.7 and 5.7 ± 1.3, respectively; while in cancer tissues, gene relative expression levels were 53.7 ± 8.3, 66.7 ± 5.2 and 61.0 ± 3.1, respectively, which was significantly increased. As detected by MTT, relative cell survival rate within 12 h of survivin overexpression were: load control group (88.5 ± 1.6)%; overexpressed group (90.3 ± 1.9)%. Transwell invasion assay results indicated that overexpressed survivin could significantly increase the relative survival rate of cells.ConclusionsExpressions of p53, Ki67 and survivin are increased in cancer; and there is a positive correlation between survivin, p53 and Ki67 expressions in laryngeal carcinoma

A review of ammonia-oxidizing bacteria and archaea in Chinese soils

Ammonia (NH3) oxidation, the first and rate-limiting step of nitrification, is a key step in the global Nitrogen (N) cycle. Major advances have been made in recent years in our knowledge and understanding of the microbial communities involved ammonia oxidation in a wide range of habitats, including Chinese agricultural soils. In this mini-review, we focus our attention on the distribution and community diversity of ammonia-oxidizing bacteria (AOB) and ammonia oxidizing archaea (AOA) in Chinese soils with variable soil properties and soil management practices. The niche differentiation of AOB and AOA in contrasting soils have been functionally demonstrated using DNA-SIP (stable isotope probing) methods, which have shown that AOA dominate nitrification processes in acidic soils, while AOB dominated in neutral, alkaline and N-rich soils. Finally, we discuss the composition and activity of ammonia oxidizer in paddy soils, as well as the mitigation of the greenhouse gas nitrous oxide (N2O) emissions and nitrate leaching via inhibition of nitrification by both AOB and AOA

Z3-connectivity of 4-edge-connected 2-triangular graphs

AbstractA graph G is k-triangular if each edge of G is in at least k triangles. It is conjectured that every 4-edge-connected 1-triangular graph admits a nowhere-zero Z3-flow. However, it has been proved that not all such graphs are Z3-connected. In this paper, we show that every 4-edge-connected 2-triangular graph is Z3-connected. The result is best possible. This result provides evidence to support the Z3-connectivity conjecture by Jaeger et al that every 5-edge-connected graph is Z3-connected