Thiosuccinimide enabled S-N bond formation to access N-sulfenylated sulfonamide derivatives with synthetic diversity.

A thiosuccinimide enabled S-N cross-coupling strategy has been established for the intermolecular N-sulfenylation of clinically approved sulfa drugs under additive-free conditions. This approach features simple operation, high chemoselectivity for sulfenylating the phenylamino group of sulfonamides, wide substrate scope, and easy scale production, affording N-sulfenylated products in moderate to excellent yields (up to 90%). In addition, we also found that this transformation can be realized in a one-pot manner by employing readily available thiols as starting materials, and the obtained sulfonamide derivatives are capable of various late-stage functionalizations, including oxidation, arylation, benzylation, and methylation.

Construction of a High-Density Recombination Bin-Based Genetic Map Facilitates High-Resolution Mapping of a Major QTL Underlying Anthocyanin Pigmentation in Eggplant.

High-density genetic maps can significantly improve the resolution of QTL mapping. We constructed a high-density recombination bin-based genetic map of eggplant based on 200 F2 plants from an interspecific cross (Solanum melongena × S. incanum) using the whole genome resequencing strategy. The map was 2022.8 cM long, covering near 99% of the eggplant genome. The map contained 3776 bins, with 3644 (96.5%) being effective (position non-redundant) ones, giving a nominal average distance of 0.54 cM and an effective average distance of 0.56 cM between adjacent bins, respectively. Using this map and 172 F2:3 lines, a major QTL with pleiotropic effects on two anthocyanin pigmentation-related traits, leaf vein color (LVC) and fruit pericarp color (FPC), was steadily detected in a bin interval of 2.28 cM (or 1.68 Mb) on chromosome E10 in two cropping seasons, explaining ~65% and 55% of the phenotypic variation in LVC and FPC, respectively. Genome-wide association analysis in this population validated the QTL and demonstrated the correctness of mapping two bins of chromosome E02 onto E10. Bioinformatics analysis suggested that a WDR protein gene inside the bin interval with reliable effective variation between the two parents could be a possible candidate gene of the QTL.

Determination of absorption dose in chemical mutagenesis in plants.

Chemical mutagenesis is a useful tool for inducing mutations in plants. Seeds are often used as the material for chemical mutagenesis. The biological effect of a chemical mutagen on seeds is determined by absorption dose (the product of mutagen concentration and acting time, which starts after the mutagen is absorbed by the seeds). In practice, however, the concept of exposure dose (the product of mutagen concentration and treating time) is usually used instead because the time for absorbing mutagen is unknown. In this study, we conducted an experiment using ethyl methane sulphonate (EMS) to treat cauliflower seeds, in which five EMS concentrations (0%, 0.5%, 1.0%, 1.5% and 2.0%), three treating time lengths (4 h, 6 h and 8 h) and two pretreatments (non-presoaking and presoaking of seeds for 2 h) were set. We obtained a well-fitted nonlinear regression model for the relationship between seedling survival rate and the EMS treatment, and its marginal models for the two pretreatments. Based on the models, we determined the EMS absorption doses under the two different pretreatments and identified their 50% lethality dose (LD50). We found that presoaking could delay EMS absorption and therefore reduce the injury caused by EMS within a given treating time, but could hardly change the biological effect of EMS after it is absorbed. The conclusions about absorption dose and presoaking effect obtained in this study might be generally applicable to plant chemical mutagenesis in principle.

Clinical experience of the treatment of giant congenital benign tumours of the back.

Congenital giant benign tumours of the back are rarely seen or reported. They pose two challenges to plastic surgeons: copious intraoperative bleeding, and an extensive raw area left after removal of the tumour. We have treated five cases of congenital giant benign tumour of the back. The largest was a neurofibroma in a woman, which weighed 36.29 kg and she had 10,000 ml of blood transfused to replace the blood loss during operation. We achieved total excision of the tumours in all cases and covered the extensive wounds with skin harvested from the tumours themselves in one stage. Among the five cases, four were neurofibromas and one was a giant naevus. All grafted skin took, and there were no recurrences. The tumours were radically excised in one stage and the extensive wounds covered with the skin with good take and no risk of recurrence.

New experiences in treating postburn talipes equinovarus associated with bone and joint pathologic changes.

This article aims to solve the problem of postburn talipes equinovarus associated with bone and joint pathologic changes by simplified and modified techniques. In addition to lengthening the shortened Achilles tendon and the contracted scar above it, we performed triple arthrodesis directly on the densely scarred, deformed foot without replacing the scar tissue with normal tissue tube or flap. Only the proximal scar-periosteum wound edge of the curved incision, 2 cm distal to the conventional one, was elevated to expose the bones to be excised. The two excised wedge-shaped bone blocks, one on the dorsum and the other on the lateral side of the deformed foot, were composed of a larger part of the talus and lesser parts of the navicular, cuboid and calcaneus bones. All the patients who could not stand or walk without crutches pre-operatively obtained a good operative result, which enabled them to do so without crutches postoperatively. We conclude that the scar tissue can be elevated without risk of necrosis if it is still attached firmly to the underlying periosteum, and arthrodesis can be done under it. Incision wound healing and bone union is not exclusively a problem.

Expanded scarred or skin-grafted forehead flap for nasal reconstruction in severe postburn facial deformity.

Loss of the nose is one of the sequelae of the severe facial burn and requires total nasal reconstruction. Many traditional techniques were used but the result was not good in terms of skin color and texture match. For those patients who suffered from full face burn associated with nasal defect but retained smooth atrophic scars or grafted skin on the integrate frontalis, the expansion of the scarred forehead was chosen to reconstruct a new nose. Generally, the patients underwent 3 stages of operation. Fifty-two cases of nasal defects were reconstructed successfully with satisfactory results. The reconstructed nose manifested similar color and texture to the postburn face, and the new noses had no sign of shrinkage, flattening, or collapse. Expanded scarred forehead flap for nasal reconstruction could obtain a new nose with similar skin color and texture to its adjacent postburn face.

Use of autologous tissue engineered skin to treat porcine full-thickness skin defects.

OBJECTIVE: To explore a feasible method to repair full-thickness skin defects utilizing tissue engineered techniques. METHODS: The Changfeng hybrid swines were used and the skin specimens were cut from the posterior limb girdle region, from which the keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA, and type II collagenase. The cells were seeded in Petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with trypsin to separate them from the floor of the tissue culture dishes. A biodegradable material, Pluronic F-127, was prefabricated and mixed with these cells, and then the cell-Pluronic compounds were seeded evenly into a polyglycolic acid (PGA). Then the constructs were replanted to the autologous animals to repair the full-thickness skin defects. Histology and immunohistochemistry of the neotissue were observed in 1, 2, 4, and 8 postoperative weeks. RESULTS: The cell-Pluronic F-127-PGA compounds repaired autologous full-thickness skin defects 1 week after implantation. Histologically, the tissue engineered skin was similar to the normal skin with stratified epidermis overlying a moderately thick collageneous dermis. Three of the structural proteins in the epidermal basement membrane zone, type IV collagen, laminin, and type VII collagen were detected using immunohistochemical methods. CONCLUSIONS: By studying the histology and immunohistochemistry of the neotissue, the bioengineered skin graft holds great promise for improving healing of the skin defects.

[Effects of hVEGF cDNA on random skin flap via a replication-deficient adenovirus vector].

OBJECTIVE: The purpose of this study was to determine the effects of local delivery of vascular endothelial growth factor( VEGF) transferred with adenovirus-mediated gene on the survival of ischemic random skin flap in rats. METHODS: The animals were divided into three groups randomly (n = 10) . A 2 cm x 8 cm dorsal skin flap was designed with the pedicle at the level of the iliac crest. In group A (AdCMV-VEGF), each animal received 10(12) PR replication-deficient recombinant adenovirus (AdCMV-VEGF) in the distal two-thirds of the proposed flap by means of the subdermal injection at ten different locations. In group B (AdCMV-GaI), each received 1012 PR AdCMV-Gal. In Group C (Saline), each received 1 ml saline. Three days after the treatment, the flap was elevated as planed way and re-sutured back to its donor site. All the animals were evaluated 7 days after the operation. RESULTS: The mean percentage of surviving flap area was (85.91 +/- 2.54)% in group A, (59.56 +/- l.18)% in group B, and (61.48 +/- l.09)% in group C. There was a significant increase in the percentage of the survival area in the flaps of the group A, compared with the group B and group C (Group B vs. Group A, P < 0.01; Group C vs.Group A, P < 0.01, Group B vs. Group C, P >0.05). Hybridization in the situ, the immunohistochemical stain showed that the VEGF was expressed in the survival tissue of the flap treated with the AdCMV-VEGF, but it was not found in the control groups. Histological analysis demonstrated qualitatively greater amount of granulation tissue and angiogenesis was found in the group treated with the AdCMV-VEGF than the controls. CONCLUSIONS: The results may indicate that Ad vector carrying VEGF cDNA could be useful in enhancing the survival of the skin flap due to the effect of the local delivery of the VEGF.

Effect of adenovirus-mediated gene transfection of vascular endothelial growth factor on survival of random flaps in rats.

OBJECTIVE: To evaluate the effect of local application of vascular endothelial growth factor (VEGF) via adenovirus-mediated gene transfer on survival of full thickness flaps selected randomly in rats. METHODS: Thirty Sprague-Dawley rats weighing 480-520 g were used in this study. A dorsal flap (8 cm x 2 cm) in full thickness with the pedicle located at the level of the iliac crest was designed. Then the rats received 1,012 pfu replication-deficient recombinant adenovirus carrying VEGF (AdCMV-VEGF group, n=10), 1,012 pfu recombinant beta-galactosidase adenovirus (AdCMV-Gal group, n=10) and 1 ml saline (saline group, n=10), respectively, in the distal two thirds of the proposed flap by means of subdermal injection at 8 different locations. Three days after treatment, the flaps were elevated as originally designed and sutured back in situ. The survival rate of the flaps was evaluated on day 7 after operation. RESULTS: The survival rate of the flaps in the AdCMV-VEGF group increased significantly as compared with those of the AdCMV-Gal group (P<0.01) and the saline group (P<0.01). Immunohistochemical staining showed that VEGF was expressed in the survival flaps injected with AdCMV-VEGF. Histological analysis showed that more granulation tissues and angiogenesis were observed in the AdCMV-VEGF group than those in the AdCMV-Gal and the saline groups. CONCLUSIONS: Local application of adenovirus-mediated VEGF165 cDNA may efficiently improve the survival of ischemic skin flaps.

[Repair of porcine full-thickness skin defects with autologous tissue engineered skin].

OBJECTIVE: To explore a feasible method to repair full-thickness skin defects with tissue engineered techniques. METHODS: The skin specimens were cut from the Changfeng hybrid swines' abdomen, then keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA and type II collagenase. The cells were seeded in petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with dispase II (keratinocytes) or trypsin (fibroblasts) to separate them from the floor of the tissue culture dishes. A biodegradable material-pluronic F-127 was prefabricated and mixed with these cells, and then the cells-pluronic compounds were seeded evenly into polyglycolic acid (PGA). Tinally the constructs were replanted to autologous animals to repair full-thickness skin defects. Histological changes were observed in 1, 2, 4 and 8 weeks postsurgery. RESULTS: The cells-pluronic F-127-PGA compounds could repair autologous full-thickness skin defects. Histologically, the tissue engineered skin was similar to normal skin with stratified epidermis overlying a moderately thick collageneous dermis. CONCLUSION: Tissue engineered skin can repair autologous full-thickness skin defects with primary-cultured keratinocytes and fibroblasts as seed cells and PGA as a cell carrier.

[Intra-uterine model of cleft lip and scarless wound healing of fetal rats].

OBJECTIVE: To properly evaluate the benefits of in utero repair of cleft lip, an animal model of cleft lip was developed and the fetal scarless wound healing was observed in SD rat fetus. METHODS: Through a maternal celiotomy and hysterotomy, twenty excisional cleft was created in the upper lip of rat fetus. Another group of 20 rat fetus were given full-thickness incisional wounds in the upper lips. The fetus with cleft lip were returned into utero for further development till birth.Wound specimens from the incisional wounds in the other group were removed successively 12, 24, 48, 72h postwounding for histological examination. RESULTS: The fetus with excisional wound demonstrated a complete cleft lip after birth. In contrast, the wound in the fetus with incisional wounds regenerated with normal architecture histologically, indistinguishable from the surrounding normal skin. CONCLUSION: The results of this preliminary study indicates that the fetal rat cleft lip is technically feasible with an excellent survival rate. Healing occurs without scar formation. This model will be used to document facial growth following in utero repair of a cleft lip.