Electrochemical Sulfonylation/Cyclization of N-Alkenylacrylamides with Sodium Sulfinates or Sulfonyl Hydrazides.

Two general protocols for the regioselective electrochemically enabled sulfonylation cyclization of N-alkenylacrylamides with sodium sulfinates or sulfonyl hydrazides were described. These methods were carried out under mild, chemical oxidant-free, and transition-metal-free conditions with a broad substrate scope and good functional group tolerance to provide sulfonyl-containing 4-pyrrolin-2-ones, which is readily scalable to the gram scale.

[Influence of Wnt-1 recombinant adenovirus on differentiation of human epidermal stem cells].

OBJECTIVE: To observe the influence of Wnt-1 recombinant adenovirus on differentiation tendency of human epidermal stem cells. METHODS: Wnt-1 recombinant adenovirus was transduced into hESCs (E group), while normal hESCs were used as control (C) group. The diameter, proliferation,and labeling molecular expression of hESC were determined. The content of MMP-2 and MMP-7 in supernate were also assayed. RESULTS: There was no obvious difference in diameter of hESC between two groups. The density of hESC in E group was (1.45 +/- 0.09) x 10(5)/mL, which was obviously higher than that in C group [(1.18 +/- 0.10) x 10(5)/mL, P < 0.05]. There were no obvious differences in expression of markers between two groups,including keratin 5 (KS), K6, K7, KS, K14, CD44, carcinoembryonic-like antigen (CEAA), ER, PR (P > 0.05) ,while the expression of K 10 was different among groups [(60 +/- 3)% in E group, 0 in C group], also K18 [(34.3 +/- 2.1)% in E group vs. (13.8 +/- 1.7)% in C group, P < 0.05], and K19 [(17.1 +/- 1.8)% in E group vs. (24.4 +/- 1.5)% in C group, P < 0.05].The contents of MMP-2 and MMP-7 in E group were higher than those in C group (P < 0.01). CONCLUSION: Wnt-1 recombinant adenovirus can induce the differentiation of hESCs to glandular epithelium-like cells.

[Histologic characteristics of in vitro constructed skin basement membrane].

OBJECTIVE: To observe the histological characteristics of constructed basement membrane in tissue-engineered skin. METHODS: Forskins from circumcision in normal children were obtained with informed consent of the parents, and then the epidermal keratinocytes (KC) and dermal fibroblasts (Fb) were isolated with trypsin and collagenase D digestion in sequence. Tissue engineered skin with composite chitosan was maintained in a submerged state for 3 days, and then at the air-liquid interface. The tissue-engineered skins were fixed in neutral formalin and then embedded in paraffin after culture for 7, 10 and 15 days, respectively for immunohistological examination of the basement membrane component,including the condition of collagen type IV (COL-IV), collagen type VII (COL-VII), and laminin (LN). RESULTS: HE staining showed that the keratinocytes formed a fine stratified squamous epithelium with the presence of basal, spinous, granular and corneous cell layers, and there was various amount of cells in flat and fusiform shape in each layer. It was found that a regular red staining strip situated at the dermal epidermal junction. Positive staining of collagen IV, collagen VII as well as LN was observed by immunohistological examination. CONCLUSION: The results suggest that the composite chitosan tissue engineered skin has a good prospect for clinical use because it presents a perfect reconstruction of basement membrane.