[Effects of sericine on TGF-beta1/Smad3 signal pathway of diabetic mephropathy rats kidney].

OBJECTIVE: To observe the effects of color silk cocoon extraction-sericine on transforming growth factor-beta1 (TGF-beta1) and Smad3 protein expression in kidney of diabetic nephropathy (DN) rats. METHODS: 60 male SD rats were randomly divided into 5 groups (n = 12): normal control group, DN model group, sericine treatment group, metformin group and sericine prevention group. The rats in model group, sericine treatment group, metformin group and sericine prevention group were all established DN rats model by intraperitoneally injected streptozotocin (STZ). Blood glucose > or = 16.7 mmol/L was taken as standard to judge if the rats model were successfully established. After the rats model were successfully established, the rats in sericine treatment group were lavaged with sericine (2.4 g/(kg x d), 35 d). The rats in metformin group were lavaged with metformin (55.33 mg/(kg x d), 35 d). The rats in sericine prevention group were lavaged with the same dose sericine for 35 d before injecting STZ. The blood glucose and kidney weight/body weight of rats in each group were respectively detected. Immunohistochemical staining was used to observe the expression of TGF-beta1 and Western blot to detect the expression of Smad3 in kidney. RESULTS: Compared with normal control rats: the blood glucose, kidney weight/body weight, TGF-beta1 and Smad3 expression in kidney of rats in model group increased obviously (P < 0.01). The blood glucose, TGF-beta1 and Smad3 expression in kidney of rats in sericin treatment group, sericin prevention group and metformin group were significantly lower than that of model group (P < 0.01). Moreover, there were no obvious differences between sericin treatment group, sericin prevention group and metformin group (P > 0.05). The kidney weight/body weight of rats in sericin treatment group, sericin prevention group and metformin group were significantly lower than that of model group (P < 0.01). Moreover, the kidney weight/body weight of rats in sericin treatment group and sericin prevention group were obviously lower than that of metformin group (P < 0.05). CONCLUSION: Sericin can inhibit activation of TGF-beta1/Smad3 signal pathway in kidney of DN rats, lighten glomerulosclerosis and renal interstitial fibrosis, so has protective and preventive effects on kidney injury of DN rats. Moreover, the therapeutical and preventive effects of sericin on DN are similar with metformin.

[Influence of soil moisture, nitrogen and phosphorus contents on Bauhinia faberi seedlings growth characteristics in arid valley of Minjiang River].

To study the influence of resources thresholds on plant growth is a major theme in restoration ecology. Based on the simulation of the natural thresholds of soil moisture, nitrogen (N), and phosphorus (P) under drought condition in the arid valley of Mingjiang River, a full factorial experiment was designed to study the dynamics of Bauhinia faberi seedlings survival rate, growth, biomass production, and resources use efficiency across one growth season. High soil moisture (40% field water capacity), high soil P (24 mg P x kg(-1)), and low N (100 mg N x kg(-1)) increased the seedlings survival rate, and promoted the seedlings growth, biomass production, and water use efficiency. There was a significant coupling effect between soil N and P, but the interactions between soil moisture and soil N and P were not obvious. High N (240 mg N x kg(-1)) restrained the seedlings growth markedly, while high P mitigated the negative effects of high N via increasing root area, root length, and root mass to promote the seedlings N and P uptake. The N and P use efficiency across one growth season kept steady, and had significant positive correlation with root/shoot mass ratio. The combination of high soil moisture, low N, and high P promoted the seedlings growth effectively, while that of low soil moisture, low P, and high N inhibited the seedlings growth markedly.

[Preparation and evaluation in vivo of Scutellaria thermosensitive gel].

OBJECTIVE: To study scutellaria thermosensitive gel in situ. METHOD: The phase transition temperature of gel with various concentration polymer solutions was studied by using stirring method and the viscosity of gel was monitored under different temperatures. Eye irritation experiments were performed with rabbit. The duration of residence time in rabbit eyes of scutellaria thermosensitive gel was observed with 2% fluorescein. RESULT: 20% poloxmar407 and 10% poloxmar 188 were suitable to scutellaria thermosen-sitive gel in situ. The results suggested that the scutellaria thermosensitive gel in situ based on poloxmar were nonirritant and retention time on the surface of eye was (150 +/- 8) min. CONCLUSION: The scutellaria thermosensitive gel in situ forms gel in eye and has longer release time than that of eye drops.