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Stress can induce microspores to change their developmental pathway from the gametophytic to the embryogenic pathway. To explore the molecular mechanisms of microspore embryogenesis, complement DNA-amplified fragment length polymorphism was used to isolate the transcript-derived fragments during microspore embryogenesis of the non-heading Brassica campestris L. ssp. chinensis ‘Wuyueman’. With 256 primer combinations screened, a total of 94 transcript-derived fragments were identified, and 15 were successfully sequenced. Based on a BLAST search in the Brassica database, 12 of the 15 sequenced transcript-derived fragments were homologous to genes with annotations; the remaining three transcript-derived fragments did not match any sequences. Transcript-derived fragments with annotations were involved in cell wall formation, hormones, and resistance. Analysis of cis-elements indicated that there were heat shock-related and stress-related cis-elements in the promoter sequences of 12 transcript-derived fragments. TDF1(Bra040720), TDF6(Bra013664), and TDF15(Bra022587) were selected for validation of complement DNA-amplified fragment length polymorphism expression patterns by real-time quantitative PCR. Results confirmed the altered expression patterns of three genes revealed by the complement DNA-amplified fragment length polymorphism. This study provides novel information on the molecular mechanism of microspore embryogenesis in non-heading Chinese cabbage.

SBP-box (Squamosa-promoter binding protein) genes are a type of plant-specific transcription factor and play important roles in plant growth, signal transduction and stress response. However, little is known about the SBP-box genes in pepper (CaSBP), especially in the process of Phytophthora capsici infection. In this study, a novel gene (CaSBP12) was selected from the CaSBP gene family, which was isolated from the pepper genome database in our previous study. The CaSBP12 gene was located in the nucleus of the cell and its silencing in the pepper plant enhanced the defense response against Phytophthora capsici infection. After inoculation with Phytophthora capsici, the root activity of the CaSBP12-silenced plants is compared to control plants, while malondialdehyde (MDA) content is compared viceversa. Additionally, the expression of defense related genes (CaPO1, CaSAR8.2, CaBPR1, and CaDEF1) in the silenced plants were induced to different degrees and the peak of CaSAR8.2 and CaBPR1 were higher than that of CaDEF1. The CaSBP12 over-expressed Nicotiana benthamiana plants were more susceptible to Phytophthora capsici infection with higher EC (electrical conductivity) and MDA contents as compared to the wild-type. The relative expression of defense related genes (NbDEF, NbNPR1, NbPR1a, and NbPR1b) in transgenic and wild-type Nicotiana benthamiana plants were induced, especially the NbPR1a and NbPR1b. In conclusion, these results indicate that CaSBP12 gene negative regulates the defense response against Phytophthora capsici infection which suggests their potentially significant role in plant defense. To our knowledge, this is the first report on CaSBP gene which negative regulate defense response.

To evaluate the feasibility, clinical effect and safety of vaginal myomectomy.From January 2002 to April 2004, 45 cases treated by vaginal myomectomy were analyzed as the study group, and 45 cases treated by abdominal myomectomy during the same period in our hospital were selected as the control group. Effects of operation and recovery of two groups were compared.There were no significant differences in the mean operating time, blood loss during operation between the study group, (76 +/- 21) minutes, (414 +/- 73) ml and the control group, (72 +/- 26) minutes, (404 +/- 68) ml. In the study group, the mean recovery time of bowel function (18 +/- 9) hours and average postoperative hospital stay (4.8 +/- 0.6) days were shorter than in the control group (31 +/- 8) hours, (7.8 +/- 0.4) days. For two groups menorrhagia were relieved after 6.8 months' follow-up, patients in the study group recovered more rapidly and felt more satisfactory with the effect of operation than patients in the control group.Vaginal myomectomy can be performed in selected patients with minimum operative injury, low complications and good short-time effect compared with abdominal myomectomy.