The Antibiosis Action and Rice-Induced Resistance, Mediated by a Lipopeptide from Bacillus amyloliquefaciens B014, in Controlling Rice Disease Caused by Xanthomonas oryzae pv. oryzae.

In the present study, a lipopeptide (named AXLP14) antagonistic to Xanthomonas oryzae pv. oryzae (Xoo) was obtained from the culture supernatant of Bacillus amyloliquefaciens B014. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis demonstrated that AXLP14 consisted of surfactin homologs. The minimum inhibition concentration and minimum bactericidal concentration of AXLP14 against Xoo were determined to be 1.25 and 2.50 mg/ml, respectively. At a concentration of 0.613 mg/ml, AXLP14 strongly inhibited the formation of Xoo biofilm. AXLP14 also inhibited the motility of Xoo in a concentration-dependent manner. Applying AXLP14 to rice seedlings significantly reduced the incidence and severity of disease caused by Xoo. In Xoo-infected rice seedlings, AXLP14 strongly and continuously up-regulated the expression of both OsNPR1 and OsWRKY45. In addition, AXLP14 effectively inhibited the Xoo-induced up-regulation of the expression of the abscisic acid biosynthesis gene OsNECD3 and the abscisic acid signalingresponsive gene OsLip9, indicating that AXLP14 may protect rice against Xoo-induced disease by enhancing salicylic acid defense and interfering with the abscisic acid response to virulence.

[Use of recombinant human luteinizing hormone for ovulation stimulation in in vitro fertilization-embryo transfer].

OBJECTIVE: To evaluate application of recombinant human luteinizing hormone (r-hLH) used in ovarian stimulation of assisted reproductive technique and impact on outcome of pregnancy. METHODS: From Apr. to Jul. 2009, 123 patients with low LH level (< 1 U/L) at day 3 of menstruation and down-regulation of pituitary function undergoing in vitro fertilization-embryo transfer (IVF-ET) in Reproductive Medical Center, Provincial Hospital Affiliated to Shandong University were enrolled in this study, whom were classified into 66 cases treated by r-hLH in r-hLH group and 57 cases without r-hLH treatment in non-r-hLH group. In the mean time, 145 patients with normal level of serum LH (1 - 2 U/L) not given by r-hLH treatment and undergoing IVF-ET were matched as control group. Total amount of gonadotropin, estradiol levels and LH levels on the administration of human chorionic gonadotropin (hCG), number of oocytes retrieved, number of 2PN zygotes, rate of high quality embryos, the rates of implantation and clinical pregnancy were compared among these three groups. RESULTS: The level of serum LH on the day of hCG administration were (1.59 ± 0.77) U/L in r-hLH group, (0.54 ± 0.25) U/L in non-r-hLH group and (2.39 ± 1.01) U/L in control group, which reached statistical difference between every two groups (P < 0.05). The rates of high quality embryo were 59.36% in r-hLH group, 57.79% in non-r-hLH group, which were significantly lower than 65.94% in control group, respectively (P < 0.05). The rates of 2PN were 67.62% in r-hLH group and 68.32% in control group, which were significantly higher than 62.84% in non-r-hLH group, respectively (P < 0.05). The rates of implantation of 29.77% in r-hLH group were significantly higher than 18.26% in non-r-hLH group (P < 0.05). The total amount of gonadotropin, estradiol level on the day of hCG administration, the number of oocytes retrieved, and clinical pregnancy rate were not significantly different among those three groups (P > 0.05). CONCLUSION: The administration of recombinant human luteinizing hormone in patients who are profoundly suppressed after down-regulation with long protocol can get more quality embryos, the higher rates of 2PN and implantation.