Single-cell transcriptome atlas reveals spatiotemporal developmental trajectories in the basal roots of moso bamboo (Phyllostachys edulis).

Roots are essential for plant growth and development. Bamboo is a large Poaceae perennial with 1642 species worldwide. However, little is known about the transcriptional atlas that underpins root cell-type differentiation. Here, we set up a modified protocol for protoplast preparation and report single-cell transcriptomes of 14 279 filtered single cells derived from the basal root tips of moso bamboo. We identified four cell types and defined new cell-type-specific marker genes for the basal root. We reconstructed the developmental trajectories of the root cap, epidermis, and ground tissues and elucidated critical factors regulating cell fate determination. According to in situ hybridization and pseudotime trajectory analysis, the root cap and epidermis originated from a common initial cell lineage, revealing the particularity of bamboo basal root development. We further identified key regulatory factors for the differentiation of these cells and indicated divergent root developmental pathways between moso bamboo and rice. Additionally, PheWOX13a and PheWOX13b ectopically expressed in Arabidopsis inhibited primary root and lateral root growth and regulated the growth and development of the root cap, which was different from WOX13 orthologs in Arabidopsis. Taken together, our results offer an important resource for investigating the mechanism of root cell differentiation and root system architecture in perennial woody species of Bambusoideae.

Plasticity in the Morphology of Growing Bamboo: A Bayesian Analysis of Exogenous Treatment Effects on Plant Height, Internode Length, and Internode Numbers.

Sucrose (Suc) and gibberellin (GA) can promote the elongation of certain internodes in bamboo. However, there is a lack of field studies to support these findings and no evidence concerning how Suc and GA promote the plant height of bamboo by regulating the internode elongation and number. We investigated the plant height, the length of each internode, and the total number of internodes of Moso bamboo (Phyllostachys edulis) under exogenous Suc, GA, and control group (CTRL) treatments in the field and analyzed how Suc and GA affected the height of Moso bamboo by promoting the internode length and number. The lengths of the 10th-50th internodes were significantly increased under the exogenous Suc and GA treatments, and the number of internodes was significantly increased by the exogenous Suc treatment. The increased effect of Suc and GA exogenous treatment on the proportion of longer internodes showed a weakening trend near the plant height of 15-16 m compared with the CTRL, suggesting that these exogenous treatments may be more effective in regions where bamboo growth is suboptimal. This study demonstrated that both the exogenous Suc and GA treatments could promote internode elongation of Moso bamboo in the field. The exogenous GA treatment had a stronger effect on internode elongation, and the exogenous Suc treatment had a stronger effect on increasing the internode numbers. The increase in plant height by the exogenous Suc and GA treatments was promoted by the co-elongation of most internodes or the increase in the proportion of longer internodes.

Etiology, treatment, and reproductive prognosis of women with moderate-to-severe intrauterine adhesions.

OBJECTIVE: To analyze data from the hysteroscopic adhesiolysis of moderate-to-severe intrauterine adhesions (IUAs), and to review the disease etiology, changes in menstruation, uterine recovery, and reproductive prognosis of women after comprehensive therapy. METHODS: In a retrospective descriptive analysis, clinical data were assessed from 683 patients with moderate-to-severe IUAs who were treated by hysteroscopic adhesiolysis at Third Xiangya Hospital, Changsha, China, between January 2007 and December 2011. Patients underwent comprehensive treatment. After hysteroscopic adhesiolysis, a persistent balloon urinary catheter was inserted, together with an intrauterine device (IUD). Intrauterine sodium hyaluronate gel was injected to prevent adhesion reformation, and oral estrogen was administered to promote endometrial regeneration. The outcomes were menstrual changes and uterine recovery under hysteroscopy, and the reproductive prognosis of patients with fertility intentions. RESULTS: At the 3-month follow-up, the postoperative recovery of uterine shape was better than the recovery of menstruation among patients with moderate-to-severe IUAs. Among the 475 patients with fertility intentions, the pregnancy and live birth rates were 66.1% (314/475) and 64.0% (201/314), respectively. CONCLUSION: Comprehensive treatment prevented the recurrence of IUAs to a certain extent, but some severe endometrial injuries were found to be irreparable, reducing the rate of subsequent pregnancy and live birth.

[Recovery of reproductive endocrine function after orthotopic fetal ovarian allotransplantation in rats].

OBJECTIVE: To assess the recovery of the reproductive endocrine function in rats following orthotopic transplantation of fetal ovarian allograft. METHODS: Ninety female SD rats (50-60 days old) were randomized into graft recipient group (n=50), positive control group (n=20), and negative control group (n=20) to receive orthotopic transplantation of fetal (17-19 gestational days) ovaries following bilateral oophorectomy, sham abdominal surgery, and bilateral oophorectomy, respectively. At 45 days after the surgeries, serum estradiol and progesterone levels were measured and the ovaries were removed for evaluation of the ovarian volume and follicle development. RESULTS: On day 45 after the operations, the estradiol or progesterone levels showed no significant difference between the recipient group and positive control group (P>0.05), but both were significantly lowered in the negative control group (P<0.05). The ovarian volume was comparable between the recipient group and positive control group (P>0.05), and optical microscopy showed follicles in different stages of development and formation of corpus luteum in the ovaries in both groups. CONCLUSION: Fetal rat ovary allografts can develop into functional ovaries capable of ovulation to restore the reproductive endocrine function of recipient female rats.