Effects of feed conditioning temperature on pellet quality, growth performance, intestinal development and blood parameters of geese from 1 to 28 d of age.

A 28-d experiment was conducted to investigate the effects of feed-conditioning temperature on the pellet quality, growth performance, intestinal development, and blood parameters of geese. A total of 180 one-day-old White Yuzhou goslings were randomly allotted to 5 treatment groups, with 6 replicates containing 6 birds each. Five diets were conditioned at 65, 70, 75, 80, and 85°C. Body weight and feed intake per pen basis were recorded from the arrival to the end of the trial. Blood and small intestine samples were collected on d 28 for analysis. The results showed that the pellet durability index (PDI), pellet hardness, and gelatinisation degree of starch (GDS) increased with increasing conditioning temperature (P < 0.05). The final body weight (FBW), average daily gain (ADG) and average daily feed intake (ADFI) of goslings significantly increased when conditioning temperature increased from 65 or 70°C to 80 or 85°C (P < 0.05), accompanied by unaffected feed conversion ratio (FCR) (P > 0.05). The villus height to crypt depth ratio (VH/CD) in the duodenum and ileum improved with increasing conditioning temperature (P < 0.05). Additionally, trypsin and amylase activity were enhanced when the conditioning temperature increased from 65 to 85°C (P < 0.05). No significant differences in the carcass traits and blood parameters of goslings were observed among the groups (P > 0.05). Overall, under the present experimental conditions, increasing the steam-conditioning temperature of pelleted feed improved pellet quality, growth performance, intestinal morphology, and digestive enzyme activity in goslings. Based on broken-line regression analysis, the lower critical conditioning temperature for ADG in geese from 1 to 28 d of age was 80.95°C.

Effects of EGCG on proliferation and apoptosis of gastric cancer SGC7901 cells via down-regulation of HIF-1α and VEGF under a hypoxic state.

OBJECTIVE: To investigate the effects of epigallocatechin-3-gallate (EGCG) on proliferation and apoptosis of human gastric cancer SGC7901 cells under a hypoxic state. MATERIALS AND METHODS: Human gastric cancer SGC7901 cells were sub-cultured, and the cobalt chloride (CoCl2) hypoxia model was established. The blank control group (normoxia group), hypoxia control group (hypoxia group) and hypoxia + different concentrations of EGCG subgroups (20, 40, 60, 80, 100 µg/mL EGCG) were set up. Cell viability was detected via methyl thiazolyl tetrazolium (MTT) assay, apoptosis was detected via flow cytometry, and expressions of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were detected via reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. RESULTS: Relatively low concentrations of EGCG (20-80 µg/mL) presented no significant inhibiting effect on SGC7901 cell growth within a short time (24 h) (p>0.05). The increasing concentration of EGCG inhibited cell proliferation under a hypoxia state (p<0.05). EGCG induced apoptosis in a dose-dependent manner under hypoxia (p<0.05). EGCG could significantly impede expressions of HIF-1α and VEGF proteins (p<0.05), and down-regulate the level of VEGF mRNA (p<0.05), but it showed no significant effect on the HIF-1α mRNA expression (p>0.05). CONCLUSIONS: EGCG inhibited cell proliferation under hypoxia via the downregulation of HIF-1α and its downstream target gene VEGF levels, providing a theoretical basis for the early diagnosis and treatment of gastric cancer in clinic.

Biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent placement to reduce fibroblast proliferation in experimental stricture in a canine model.

BACKGROUND AND STUDY AIMS: The aim of the current study was to assess whether placement of the biodegradable rapamycin-eluting nano-fiber membrane-covered metal stent is followed by less fibroblast proliferation and tissue hyperplasia compared with bare stents in experimental stricture in a dog model. METHODS: A total of 80 dog models of stricture were randomly divided into a control group (n = 20, no stent insertion), a bare stent group (BSG, n = 20, 1-week retention), and two drug-eluting stent sub-groups (DESG-1w, n = 20, 1-week retention; DESG-4w, n = 20, 4-week retention). Lower esophageal sphincter (LES) pressure, 5-minute barium height (5-mBH), and cardia diameter were assessed before, immediately after the procedure, and regularly thereafter for 6 months. Five dogs in each group were euthanized for histological examination at each follow-up assessment. RESULTS: Stent insertion was well tolerated, with similar migration rates (0 % in BSG vs. 7.5 % in DESGs; P = 0.5441). At 6 months, LES pressure and 5-mBH improved in DESG-1w (26.70 ± 5.02 mmHg and 6.50 ± 2.98 cm) and DESG-4w (20.16 ± 5.50 mmHg and 1.54 ± 0.98 cm) compared with BSG (39.94 ± 5.22 mmHg and 11.1 ± 5.46 cm) (P < 0.05), with DESG-4w being more stable than DESG-1w (P < 0.05). The cardia maintained greater patency in the DESGs (7.10 ± 3.09 mm in DESG-1w; 9.16 ± 3.77 mm in DESG-4w) than in the BSG (1.86 ± 2.45 mm; P < 0.05). Reduced peak inflammatory reactions and scarring occurred in DESGs compared with the BSG (P < 0.05), with a better outcome in DESG-4w than in DESG-1w (P < 0.05). CONCLUSIONS: In this experimental stricture model, rapamycin-eluting stents were more effective than bare stents for the reduction of fibroblast proliferation and tissue hyperplasia after stent placement. Furthermore, 4-week retention of the drug-eluting stent led to a better outcome than 1-week retention.

Evaluation of biodegradable paclitaxel-eluting nanofibre-covered metal stents for the treatment of benign cardia stricture in an experimental model.

BACKGROUND: Benign strictures at the cardia are troublesome for patients and often require repeated endoscopic treatments. Paclitaxel can reduce fibrosis. This study evaluated a biodegradable paclitaxel-eluting nanofibre-covered metal stent for the treatment of benign cardia stricture in vitro and in vivo. METHODS: Drug release was investigated in vitro at pH 7·4 and 4·0. Eighty dogs were divided randomly into four groups (each n = 20): controls (no stent), bare stent (retained for 1 week), and two drug-eluting stent (DES) groups with retention for either 1 week (DES-1w) or 4 weeks (DES-4w). Lower oesophageal sphincter pressure (LOSP) and 5-min barium height (5-mBH) were assessed before, immediately after stent deployment, at 1 week, and 1, 3 and 6 months later. Five dogs in each group were killed for histological examination at each follow-up point. RESULTS: Stent migration rates were similar (0 bare stent versus 2 DES; P = 0·548). The percentage and amount of paclitaxel released in vitro was higher at pH 4·0 than at pH 7·4. After 6 months, LOSP and 5-mBH were both improved in the DES-1w (P = 0·004 and P = 0·049) and DES-4w (both P < 0·001) groups compared with the bare-stent group, with better relief when the stent was retained for 4 weeks (P = 0·004 and P = 0·007). The DES was associated with a reduced peak inflammatory reaction and less scar formation compared with bare stents, especially when inserted for 4 weeks. CONCLUSION: The DES was more effective for the treatment of benign cardia stricture than bare stents in a canine model. Retention of the DES for 4 weeks led to a better clinical and pathological outcome than 1 week.