|
|
| |
| Articles
by
H. Jiang |
Total Records (
3 ) for
H. Jiang |
|
 |
| |
|
| |
H. Jiang
,
J. Wang
,
L. Che
,
Y. Lin
,
Z. Fang
and
De Wu
|
| |
The objective of this study was to investigate the effects of different calcium
sources and levels on performance and bioavailability of calcium and phosphorus
in weaning piglets. A total of 90 LY (LandracexYorkshire) weaning piglets were
randomly assigned to 2x8 factorial completely randomized arrangement. The two
calcium sources were calcium carbonate or calcium citrate; Eight dietary calcium
levels were 0.37, 0.50, 0.60, 0.70, 0.80, 0.90, 1.00 and 1.10%. Each treatment
consisted of 3 replicate pens of 2 piglets. Digestibility trial was conducted
from 29 to 32 day of experiment using the total collection method. No significant
difference was observed on average daily gain, average daily feed intake and
feed conversion rate in piglets (p>0.05) from calcium sources or interactions
between calcium sources and calcium levels. There was a quadratic response of
average daily gain to increasing calcium levels (p<0.05), with the optimum
dietary calcium level of 0.6%. Piglets receiving dietary ranging from 0.37 to
0.80 had a higher calcium, phosphorus apparent digestibility than piglets receiving
dietary ranging from 0.90 to 1.10%. Calcium citrate had significantly higher
calcium apparent digestibility than calcium carbonate in piglets (p<0.05).
It is concluded that calcium citrate is a good calcium source with comparable
in bioavailability as calcium carbonate for weaning piglets. The piglets fed
0.6% calcium grew better, regardless of dietary calcium source. |
|
|
| |
|
| |
S Eleswarapu
,
X Ge
,
Y Wang
,
J Yu
and
H. Jiang
|
| |
IGF-I is abundantly expressed in the liver under the stimulation of GH. We showed previously that expression of hepatocyte nuclear factor (HNF)-3, a liver-enriched transcription factor, was strongly stimulated by GH in bovine liver. In this study, we determined whether GH-increased HNF-3 might contribute to GH stimulation of IGF-I gene expression in bovine liver and the underlying mechanism. A sequence analysis of the bovine IGF-I promoter revealed three putative HNF-3 binding sites, which all appear to be conserved in mammals. Chromatin immunoprecipitation assays showed that GH injection increased binding of HNF-3 to the IGF-I promoter in bovine liver. Gel-shift assays indicated that one of the three putative HNF-3 binding sites, HNF-3 binding site 1, bound to the HNF-3 protein from bovine liver with high affinity. Cotransfection analyses demonstrated that this HNF-3 binding site was essential for the transcriptional response of the IGF-I promoter to HNF-3 in CHO cells and to GH in primary mouse hepatocytes. Using similar approaches, we found that GH increased binding of the signal transducer and activator of transcription 5 (STAT5) to the HNF-3 promoter in bovine liver, that this binding occurred at a conserved STAT5 binding site, and that this STAT5 binding site was necessary for the HNF-3 promoter to respond to GH. Taken together, these results suggest that in addition to direct action, GH-activated STAT5 may also indirectly stimulate IGF-I gene transcription in the liver by directly enhancing the expression of the HNF-3 gene. |
|
|
| |
|
| |
H. Jiang
,
W. Q. Zhan
,
X. Liu
and
S. X. Jiang
|
| |
The antioxidant properties of the various extracts and flavonoids prepared from Oxytropis falcate Bunge were investigated by 1,1-diphenyl-2-picryldydrazyl (DPPH) radical-scavenging assay. In the chloroform, ethyl acetate and n-butanol extracts, the ethyl acetate extract exhibited the highest antioxidant activity (IC50 = 2.05 mg mL-1). Furthermore, rhamnocitrin, kaempferol, rhamnetin, 2′,4′-dihydroxychalcone and 2′,4′, β-trihydroxy-dihydrochalcone were purified from chloroform and ethyl acetate extracts. The radical-scavenging activities of the five compounds were also measured and the results showed that kaempferol (IC50 = 0.11 mg mL-1), rhamnetin (IC50 = 0.14 mg mL-1) and rhamnocitrin (IC50 = 0.15 mg mL-1) exhibited considerable antioxidant activities, but the antioxidant activities of the two dihydrochalcones were very weak. Although these flavonoids are known, this is the first report of antioxidant activity in this plant. |
|
|
|
|
| |
|
