An extracellular matrix-inspired self-healing composite hydrogel for enhanced platelet-rich plasma-mediated chronic diabetic wound treatment

Diabetes is generally accompanied by difficult-to-heal wounds, which often lead to permanent disability and even death of patients. Because of the abundance of a variety of growth factors, platelet rich plasma (PRP) has been proven to have great clinical potential for diabetic wound treatment. However, how to suppress the explosive release of its active components while realizing adaptability to different wounds remains important for PRP therapy. Here, an injectable, self-healing, and non-specific tissue-adhesive hydrogel formed by oxidized chondroitin sulfate and carboxymethyl chitosan was designed as an encapsulation and delivery platform for PRP. With a dynamic cross-linking structural design, the hydrogel can meet the clinical demands of irregular wounds with controllable gelation and viscoelasticity. Inhibition of PRP enzymolysis as well as sustained release of its growth factors is realized with the hydrogel, enhancing cell proliferation and migration in vitro. Notably, greatly accelerated healing of full thickness wounds of diabetic skins is enabled by promoting the formation of granulation tissues, collagen deposition and angiogenesis as well as reducing inflammation in vivo. This self-healing and extracellular matrix-mimicking hydrogel provides powerful assistance to PRP therapy, enabling its promising applications for the repair and regeneration of diabetic wounds.

A Surface Diffusion Barrier Strategy toward Water-Resistant Photonic Materials for Accurate Detection of Ethanol

Photonic materials that enable visual detection of chemicals have shown great potential for wide applications in chemical, environmental, biotechnological, and food industries, but until now, using hydrophilic photonic materials for tracing water-soluble chemicals remains a major challenge due to the strong water interference. Here, we demonstrate a two-step co-assembly and subsequent surface coating strategy to develop an ethanol-sensitive and anti-water interference photonic crystal film. By using citric acid as a co-assembly phase, high ethanol sensing is realized because of the strong intermolecular affinity. By controlling the thickness of the outer polyvinyl butyral layer, selective ethanol penetration but a water barrier is enabled. Notably, the composite photonic films are free-standing, highly flexible, and controllably structurally colored. We further present using the composite film to quantitatively trace ethanol/water mixtures and potentially track drunk driving as a colorimetric sensor. The heuristic two-step modification strategy proposed in this work not only overcomes the limitation of water interference for hydrophilic colorimetric sensors but also provides references to develop more new photonic materials with water resistance that need to be applied in water/humid environments.

[Synchronous multicentric osteosarcoma: treatment and prognostic factor analysis]

Objective: To identify the clinical outcome and prognostic factors of synchronous multicentric osteosarcoma (SMOS). Methods: The clinical data of 2 602 conventional osteosarcoma patients admitted to Beijing Jishuitan Hospital from January 1995 to June 2018 were retrospectively analyzed. Finally, 56 (2.1%) cases were confirmed as SMOS according to clinical and imaging database, medical record and pathological results.All epidemiological data of SMOS cases,initial diagnosis time, tumor site, number of lesions, chemotherapy, surgical treatment, alkline phosphatase (AKP),lactate dehydrogenase (LDH) and oncological results were collected in our institution. The Survival rate, comparison of various parameters, univariate analysis and multivariate Cox regression were performed with statistical software. Results: There were 41 males and 15 females enrolled in this research, the median and mean ages were 15 and 18 years (range, 8-50 years) respectively. All of them were multi-site involved, whereas the initial complaints of sites distribution were 32 cases of femur, 13 cases of tibia, 4 cases of humerus, 3 cases of fibula, 2 cases of spine, 1 case of sternum and 1 case of calcaneus. Forty-four of 56 cases performed adjuvant chemotherapy and 31 of them underwent surgical treatment. The mean follow-up time was 15.4 (range, 1-186) months. Thirty-five cases died of disease at the end of the follow-up. The 5-year survival rate was 10.4%. According to the number of lesions stratification, the 2-year survival rates in patients with low (<5 sites) and high (≥5 sites) tumor load was 33.6% and 0, respectively (χ(2)=6.697, P=0.010). The 2-year survival rate of chemotherapy and non-chemotherapy patients was 20.8% and 0, respectively (χ(2)=6.998, P=0.008), the value of AKP after chemotherapy(median: 272 IU/L) significantly decreased when compared with that at the initial diagnosis (median: 454 U/L) (Z=-3.274, P=0.001).The 2-year survival rate in patients with and without standard chemotherapy was 55.6% and 0, respectively (χ(2)=8.798, P=0.003). The 2-year survival rate was 25.0% in the surgical group and 0 in the non-surgical group, respectively (χ(2)=7.942, P=0.005). Multivariate cox regression analysis with the forward Wald method indicated that standard chemotherapy was the only variable contributor to survival and prognosis of multifocal osteosarcoma. Conclusions: SMOS has low survival rate and poor prognosis. Chemotherapy and surgery can improve the survival rate, standard chemotherapy is an independent prognostic factor.

Role of glycoconjugates in adherence of Salmonella pullorum to the intestinal epithelium of chicks

1. The distribution of glycoconjugates on the surface of Salmonella pullorum and the ileal epithelium of chicks was demonstrated by lectin cytochemistry. The role of glycoconjugates in adherence of S. pullorum to the ileal epithelium was determined by a sugar inhibition assay using the scanning electron microscope. 2. S. pullorum exhibited binding to Concanavalin A (Con A) and wheat germ agglutinin (WGA) but not to soyabean agglutinin (SBA), Ricinus communis agglutinin (RCA) and Ulex europaeus agglutinin (UEA). 3. The ileal epithelium of chicks bound WGA, Con A and SBA. The binding sites for WGA were on the brush border and cytoplasm of columnar enterocytes as well as on goblet cells. The binding of Con A was confined to the cytoplasm of columnar enterocytes, while SBA bound, in a limited way, to the brush border of columnar enterocytes. 4. After an oral dose of S. pullorum, adherence to the ileal epithelium was inhibited by methyl alpha-D-mannopyranoside.

Characterization of glycoconjugates in the endometrium of the miniature pig during different reproductive periods

Lectin-binding glycoconjugates in the endometrium of miniature pigs were determined for sexually immature, dioestrus, oestrus and early pregnancy periods, using five horseradish peroxidase-labelled lectins. Apparent changes associated with sexual maturity were increases in binding intensity of wheat germ agglutinin (WGA), Glycine max agglutinin (SBA) and Ulex europaeus agglutinin (UEA) and the appearance of Ricinus communis agglutinin (RCA) binding. The binding intensity of WGA, SBA and UEA further increased at oestrus, particularly for UEA which showed a stage-specific binding on the surface of endometrial epithelium. Pregnancy-related changes included an increase in WGA binding and a decrease in UEA and RCA binding. The results indicate that stage-specific alterations in lectin binding glycoconjugates occur in the endometrium of pigs associated with sexual maturity and the reproductive cycle.