Ontogeny of the pollinium in Hoya carnosa provides new insights into microsporogenesis.

The presence of a pollinium is a distinct character in Apocynaceae which is important for phylogenetic analysis. The pollinium of Hoya has an outer sporopollenin wall and a pellucid margin which are adaptive features. However, their ontogeny and related evolutionary implications are not entirely understood. Therefore, a representative species Hoya carnosa was selected to investigate the pollinium development using light and electron microscopy and cytochemical tests. In contrast to the microsporogenesis in most angiosperms, which is associated with callose, the non-callosic intersporal walls in Hoya carnosa, together with the successive cytokinesis and linear form of the tetrad, represent an alternative pattern of microsporogenesis. This pattern has specific implication for the early stages of pollen morphogenesis. The absence of exine and apertures in the pollen grains in the pollinium could result from a combination of factors including the absence of callose in the early stages and the modifications in later developmental pathways, e.g., the sporopollenin accumulation pathway. The pollinium wall is an exine without stratification, its surface lacks sculptures, and it provides structural support and protection. The pollen tubes germinate through the pellucid margin and germinating ridge which are specialized features. The pellucid margin originates from aborted microspores. The germinating ridge that lies on the outer side of the pellucid margin develops in the same way as a classic pollen exine. The pollen grains are aggregated by intine fusion which is favorable for tube germination and growth. Comparing Asclepiadoideae with the other two subfamilies of Apocynaceae that develop a pollinium, the pollinium of Asclepiadoideae has reduced deposition of sporopollenin in the inner walls but an increase in the outer pollinium wall, thus making the inner walls more reduced and simplified, and the outer walls more solid. The adaptive characters of the pollen wall structure and the cohesion mechanism suggest that the pollinium of Hoya carnosa is a derived form of pollen aggregation.

Higher Rate of Postoperative Complications in Delayed Achilles Tendon Repair Compared to Early Achilles Tendon Repair: A Meta-Analysis.

BACKGROUND: Some authors found that delayed repair of Achilles tendon ruptures achieved similar functional outcomes when compared with acute repair of Achilles tendon ruptures. The purpose of our study was to compare functional outcomes and complication rates of acute repair to delayed repair after Achilles tendon ruptures. METHODS: PubMed, Embase (Ovid) and the Cochrane Library were searched. RESULTS: For Achilles tendon rupture score (ATRS), the overall result revealed that there was no significant difference in ATRS between acute repair groups and delayed repair groups (P = 0.59). For Tegner scores, Halasi scores and Achilles tendon resting angle (ATRA), there was no significant difference between the two groups (P = 0.28, P = 0.47 and P = 0.68). There was no significant difference in the subjective assessment between acute repair groups and delayed repair groups (P = 0.84). However, delayed repair groups showed a higher incidence of complications than acute repair groups (P = 0.01). Subgroup analyses showed that the mean time from injury to surgery of delayed repair groups affect the pooled result substantially. For mean time less than 28d, there was no difference in the incidence of complications between acute repair groups and delayed repair groups (P = 0.09). However, for mean time more than 28d, delayed repair groups showed a higher incidence of complications than acute repair groups (P = 0.05). CONCLUSION: Our study showed delayed repair could obtain similar functional outcomes and subjective assessment when compared with acute repair. However, the rate of complications after delayed repair was higher than that of early repair. Further high-quality randomized controlled trials (RCT) are needed to evaluate the difference.

Fracture-Dedicated Prosthesis Promotes the Healing Rate of Greater Tuberosity in Reverse Shoulder Arthroplasty: A Meta-Analysis.

Introduction: Reverse shoulder arthroplasty (RSA) is becoming popular in the treatment of complex proximal humeral fractures (PHFs). Greater tuberosity healing may influence functional outcomes and range of motion (ROM) of shoulder after RSA. In addition, the design of prosthesis may impact the healing rate of greater tuberosity. The purpose of this study is to know: (1) does the healing of greater tuberosity affect the functional outcomes and ROM of shoulder? and (2) does the design of prosthesis affect the healing rate of greater tuberosity? Materials and Methods: PubMed, Ovid/Embase, and the Cochrane Library were searched for studies comparing the clinical outcomes between the healed groups and the non-healed groups after RSA. Results: For functional outcomes, the results showed that the healed group had better Constant scores (CSs) (p < 0.0001). For ROM, the healed group showed better flexion (p < 0.0001), abduction (p = 0.02), and external rotation (p < 0.00001) of shoulder. For the design of prosthesis, the mean healing rate of greater tuberosity (82.7%) in patients with fracture-dedicated prosthesis was higher than those (63.0%) in patients with standard prosthesis. Subgroup analyses showed that the CS (p = 0.12) and abduction (p = 0.96) of patients using fracture-dedicated prostheses were not different between the healed groups and the non-healed groups. Meta-regression showed that there was no significant relationship between the design of prosthesis and CS (p = 0.312), flexion (p = 0.422), or external rotation (p = 0.776). Conclusion: Our meta-analysis showed that the healed groups could obtain better functional outcomes and ROM than the non-healed groups. In addition, fracture-dedicated prostheses promoted the healing rate of greater tuberosity. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020157276, PROSPERO: CRD42020157276.

The impact of associated injuries and fracture classifications on the treatment of capitellum and trochlea fractures: A systematic review and meta-analysis.

BACKGROUND: Capitellum and trochlea fractures are truly rare and the treatment is not fully appreciated. So we evaluate the impact of associated injuries and fracture classifications on elbow functional outcomes after open reduction and internal fixation. MATERIALS AND METHODS: PubMed, Embase, Ovid Medline, and the Cochrane Library were searched from January 1, 1974 to January 1, 2017. All English literature with the treatment of capitellum and trochlea fractures by open reduction and internal fixation were included. RESULTS: For associated injuries, the results suggested that the MEPI score of patients without associated injuries was higher than that of patients with associated injuries (P = 0.001). However, there was no significant difference in the arc of motion between the two groups (P = 0.052). For Bryan and Morrey classification, there was no significant difference in the MEPI score (P = 0.622) and in the arc of motion (P = 0.652) between type-I fractures and type-IV fractures. For Dubberley classification, there was significant difference only in the MEPI score between subtype-A fractures and subtype-B fractures (P = 0.005). CONCLUSION: The associated injury of fracture may have a negative impact on the functional outcomes of elbow. And Dubberley classification is more suitable to classify this kind of fracture. Furthermore, high-quality studies are required to attain robust evidence.

Isolation of two populations of sperm cells from the pollen tube of Torenia fournieri.

The two sperm cells of Torenia fournieri are dimorphic. The dimorphic character suggests that they might be preferentially involved in fertilization during in vivo fusion with the egg cell and central cell. To probe the mechanism of preferential fertilization, it is necessary to use the most current molecular techniques. For this purpose, populations of >1000 individuals of the two dimorphic sperm cells, Sua (unassociated with the vegetative nucleus) and Svn (associated with the vegetative nucleus) were isolated from pollen tubes that had grown out of the cut ends of the styles. The two sperm cells released from pollen tubes remained attached to one another. When the two attached sperm cells were transferred into a solution containing 0.01% cellulose, 0.01% pectinase, and 5% mannitol, the connection between the two cells disappeared, and they were easily separated using a micromanipulator. The collection of these two individual populations containing over a thousand cells will permit research on gametic recognition at the molecular level.

[Treatment of knee joint pain with superficial needling].

OBJECTIVE: To compare therapeutic effects of superficial needling and body acupuncture on knee joint pain. METHODS: Ninety-six cases of knee joint pain were randomly divided into a treatment group of 48 cases treated with superficial needling, and a control group of 48 cases treated with body acupuncture. RESULTS: The cured rate was 66.7% in the treatment group and 39.6% in the control group with a significant difference between the two groups (P<0.01). The total effective rate was 100.0% in both the two groups. The needed therapeutic times of superficial needling was significantly less than that of the body acupuncture (P< 0.05). CONCLUSION: Superficial needling has a good therapeutic effect on knee joint pain with a shorter therapeutic course.

[Isolation of egg cells and zygotes from Torenia fournieri].

Torenia fournieri is a special plant with embryo sac partly protruding through the micropyle of ovule, and its egg cell, two synergids and part of the central cell can be clearly observed using light microscope (Plate I-1, 2). The feature of embryo sac of T. fournieri makes it easy to isolate egg cell and zygote, especially for physiologically mature and vigorous egg cell to study its fertilization mechanism. Egg cells of T. fournieri were isolated from embryo sacs 2 d after anthesis using enzymatic digestion or mechanical dissection after mild osmotic shock (Plate I-3, 4). About 5% egg cells (2-3 from 50 ovules) could be mechanically dissected within 2 h. When 0.1% cellulase and 0.1% pectinase were added into the solution, about 18% egg cells (8-10 from 50 ovules) could be isolated within 2 h (Plate I-5). Although egg cells could be isolated by mechanical dissection, they can be used in in vitro fertilization to probe fertilization mechanism without deleterious effect of enzymatic action on the surface of egg cell. But it is easier to isolate egg cells by using enzymatic digestion, and more egg cells can be obtained for the research of molecular biology. Using enzymatic digestion method, the zygote of Torenia fournieri was also isolated from the pollinated ovules (Plate I-7-10). Basing on our successful isolation of mature sperm cells, the isolation of egg cells of T. fournieri will make in vitro fertilization possible for the first time in a dicot plant.