Characteristics of antioxidant substances and identification of antioxidant peptides in duck embryo eggs.

1. Oxidative stress in duck embryos undergoes dynamic change during incubation. However, the detailed change characteristics has not been studied yet. Here, we explored the dynamic change characteristics of different antioxidant substances in duck embryo eggs during incubation.2. The following trial assayed antioxidant substances, including vitamins E (VE) and C (VC), glutathione (GSH), reduced glutathione (reduced GSH), oxidative glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-px), and malonic dialdehyde (MDA). Five antioxidant peptides (DY1, DY2, DY3, DY4 and DY5) were screened and their protective effect on HepG2 cells and their mechanism of action determined.3. The results showed that antioxidant substances underwent a dynamic change during incubation through various mechanisms. Moreover, the T-AOC of duck embryos at different incubation times, firstly increased and then decreased, reaching the highest level on d 15 during incubation. The peptide DY2 (TVDGPSGKLWRD) exhibited high antioxidant activity in vitro, and is known to regulate the apoptosis pathway in mitochondria.4. The data indicated that duck embryos can be used for the development of related antioxidant products and purification of new bioactive peptides.

Effects of sorghum distillers dried grains with solubles on the carcass characteristics and muscle quality of China Micro Duck drakes aged from 4 to 8 weeks.

A study was conducted to determine the effects of feeding sorghum distiller's dried grains with solubles (SDDGS) on carcasses characteristics (live weight, whole net carcass rate, breast muscle percentage, thigh muscle percentage), muscle quality (meat color, shear stress, cooking loss rate, cooked meat percentage), and meat composition of China Micro Duck (CMD) drakes aged from 4 to 8 wk. A total of 240 CMD drakes (aged 4 wk and initial weight was 496.7 g) were randomly allotted to one of 4 dietary treatments in randomized complete block design. The 4 treatments were S0(the control group, S5, S10, S15, indicating the dietary content of SDDGS (zero, 5,10 and 15%, respectively). Each treatment with 60 drakes was equally divided into 6 repeated test groups, each group with 10 drakes. The results showed that S5, S10, and S15 could decrease the thigh muscle percentage linearly (P < 0.01); however, there was no significant (p > 0.05) effect on other carcass characteristic and muscle quality indexes of live body weight (BW), whole net carcass yield (WNCY), breast muscle percentage (BMP), breast muscle color (BMC), thigh muscle color (TMC), breast shear strength (BSS), cooking loss (CL), or cooked meat percentage (CMP). For meat composition, the increasing level of SDDGS caused a linear and quadratic decrease (P < 0.01) of crude protein and a linear and quadratic (P < 0.01) increase of crude fat of thigh and breast muscle, while breast muscle ash was not significantly affected (P > 0.05). Overall, this study revealed that in the 3 kinds of diets with SDDGS, S5 had the least negative impact on carcass characteristics, muscle quality, and meat composition.

Correlation of ERCC1 expression in peripheral blood lymphocytes with outcomes of patients with gastric cancer treated with oxaliplatin-based adjuvant chemotherapy.

Excision repair cross-complementing gene-1 (ERCC1) is a key regulatory enzyme whose expression patterns in tumor tissues are associated with survival in gastric cancer. The present study aimed to evaluate the effects of ERCC1 expression in peripheral blood lymphocytes (PBLs) on the outcome of patients with gastric cancer treated with oxaliplatin-based adjuvant chemotherapy. Tumor and PBL samples from 48 patients treated with adjuvant oxaliplatin-based chemotherapy for gastric cancer were analyzed. Immunohistochemistry was used to assess the expression of ERCC1. After a median follow-up of 18.5 months, the median disease-free survival (DFS) and overall survival (OS) were 12 and 20 months, respectively. Expression of ERCC1 was found in 72.9% (35/48), 56.3% (27/48), and 10.0% (2/20) of tumor tissues, PBLs from gastric cancer patients, and PBLs from controls, respectively. A significant positive correlation between ERCC1 expression in PBL and cancer tissue was found (χ(2) = 12.098, P = 0.001, Pearson contingency coefficient = 0.502). Patients with negative expression of ERCC1 in tumor tissues had a significantly longer median DFS and median OS compared to patients with positive expression of ERCC1 (median DFS, 18 vs 10 months, P = 0.006; median OS, 30 vs 17 months, P = 0.012). In PBLs, high expression of ERCC1 was associated with decreased DFS (9 vs 18 months, P = 0.032), but not OS (16 vs 24 months, P = 0.057). Patients with gastric cancer exhibiting negative expression of ERCC1 are more likely to benefit from oxaliplatin-based adjuvant chemotherapy.