The present study aimed to prepare a composite dressing composed of collagen, chitosan, and alginate, which may promote wound healing and prevent from seawater immersion. Chitosan-collagen-alginate (CCA) cushion was prepared by paintcoat and freeze-drying, and it was attached to a polyurethane to compose CCA composite dressing. The swelling, porosity, degradation, and mechanical properties of CCA cushion were evaluated. The effects on wound healing and seawater prevention of CCA composite dressing were tested by rat wound model. Preliminary biosecurity was tested by cytotoxicity and hemocompatibility. The results revealed that CCA cushion had good water absorption and mechanical properties. A higher wound healing ratio was observed in CCA composite dressing treated rats than in gauze or chitosan treated ones. On the fifth day, the healing rates of CCA composite dressing, gauze, and chitosan were 48.49%±1.07%, 28.02%±6.4%, and 38.97%±8.53%, respectively. More fibroblast and intact re-epithelialization were observed in histological images of CCA composite dressing treated rats, and the expressions of EGF, bFGF, TGF-β, and CD31 increased significantly. CCA composite dressing showed no significant cytotoxicity, and favorable hemocompatibility. These results suggested that CCA composite dressing could prevent against seawater immersion and promote wound healing while having a good biosecurity.

Objective:To establish a quantitative method for the determination of total flavonoids in water extraction of flowers of Eriobotrya japonica(Thunb.) Lindl.by UV-VIS spectrophotometry and lay a foundation for the new food material.Methods:By use rutin as comparison sample,the effects of concentration and dosage of chromogenic reagent were studied,and NaNO2-Al (NO3) 3-NaOH colour reaction system was used for content determination of total flavonoids in the sample.The content of total flavonoids was determined at 505 nm by UV-VIS spectrophotometry.Results:There was a liner relationship from 16.48 μg/mL to 98.88 μg/mL.The regression equation was y =6.470 2x-0.003 7 (R2 =0.999 4) and the average recovery rate was 95.56％ and RSD was 3.1％.Conclution:The method is simple,rapid and accurate and can be used for the quantitative method of total flavonoids in water extraction of flowers of Eriobotrya japonica (Thunb.) Lindl.

目的 研究鲨鱼皮胶原(Shark Skin Collagen,SSC)海绵的体外抗氧化功效及其体内促伤口愈合作用.方法 采用醋酸溶胀法分离鲨鱼皮胶原,真空冷冻干燥技术制备SSC海绵,化学分光光度法检测其体外抗氧化活性;采用SD大鼠背部创伤模型,检测SSC海绵的促愈合作用,HE染色观察组织病理学变化,免疫组织化学染色法检测愈合过程中CD31,EGF和TGF-β表达变化.结果 20 mg/mL SSC溶液对HO·清除率为(84±2.1)％.术后第3、5天,SSC海绵组愈合率分别为(52.1±5.7)％、(57.1±8.0)％,显著优于纱布(gauze,GZ)组(15.9±8.3)％、(28.4±6.6)％(P＜0.01)和壳聚糖(chitosan,CS)组(22.2±9.5)％、(36.5±3.3)％(P＜0.05).HE染色显示,SSC海绵能在创伤愈合早期显著促进毛细血管、新生肉芽组织和愈合上皮生成,加速创面愈合.免疫组化检测显示,术后第3天,SSC海绵组CD31管状表达数为38±4.73,显著高于CS组27±3.06和GZ组26±3.61(P＜0.05);SSC海绵组TGF-β表达率为(20.1±3.17)％,显著高于GZ组(6.7±0.739)％和CS组(10.7±0.502)％ (P＜0.05);SSC海绵组EGF表达率为(12.1±0.447)％,显著高于GZ组(9.3±1.23)％(P＜0.05).结论 SSC具有显著的清除羟自由基功效,SSC海绵能够显著促进创伤愈合早期CD31、TGF-β和EGF的高表达,进而促进早期新血管生成和肉芽组织的形成,加快伤口愈合过程.

Wounded personnel who work at sea often encounter a plethora of difficulties. The most important of these difficulties is seawater immersion. Common medical dressings have little effect when the affected area is immersed in seawater, and only rarely dressings have been reported for the treatment of seawater-immersed wounds. The objective of this study is to develop a new dressing which should be suitable to prevent the wound from seawater immersion and to promote the wound healing. Shark skin collagen (SSC) was purified via ethanol de-sugaring and de-pigmentation and adjusted for pH. A shark skin collagen sponge (SSCS) was prepared by freeze-drying. SSCS was attached to an anti-seawater immersion polyurethane (PU) film (SSCS + PU) to compose a new dressing. The biochemical properties of SSC and physicochemical properties of SSCS were assessed by standard methods. The effects of SSCS and SSCS + PU on the healing of seawater-immersed wounds were studied using a seawater immersion rat model. For the detection of SSCS effects on seawater-immersed wounds, 12 SD rats, with four wounds created in each rat, were divided into four groups: the 3rd day group, 5th day group, 7th day group and 12th day group. In each group, six wounds were treated with SSCS, three wounds treated with chitosan served as the positive control, and three wounds treated with gauze served as the negative control. For the detection of the SSCS + PU effects on seawater-immersed wounds, 36 SD rats were divided into three groups: the gauze (GZ) + PU group, chitosan (CS) + PU group and SSCS + PU group, with 12 rats in each group, and two wounds in each rat. The wound sizes were measured to calculate the healing rate, and histomorphology and the immunohistochemistry of the CD31 and TGF-β expression levels in the wounded tissues were measured by standard methods. The results of Ultraviolet-visible (UV-vis) spectrum, Fourier-transform infrared (FTIR) spectrum, circular dichroism (CD) spectra, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and amino acid composition analyses of SSC demonstrated that SSC is type I collagen. SSCS had a homogeneous porous structure of approximately 200 μm, porosity rate of 83.57% ± 2.64%, water vapor transmission ratio (WVTR) of 4500 g/m2, tensile strength of 1.79 ± 0.41 N/mm, and elongation at break of 4.52% ± 0.01%. SSCS had significant beneficial effects on seawater-immersed wound healing. On the 3rd day, the healing rates in the GZ negative control, CS positive control and SSCS rats were 13.94% ± 5.50%, 29.40% ± 1.10% and 47.24% ± 8.40%, respectively. SSCS also enhanced TGF-β and CD31 expression in the initial stage of the healing period. The SSCS + PU dressing effectively protected wounds from seawater immersion for at least 4 h, and accelerated re-epithelialization, vascularization and granulation formation of seawater-immersed wounds in the earlier stages of wound healing, and as well as significantly promoted wound healing. The SSCS + PU dressing also enhanced expression of TGF-β and CD31. The effects of SSCS and SSCS + PU were superior to those of both the chitosan and gauze dressings. SSCS has significant positive effects on the promotion of seawater-immersed wound healing, and a SSCS + PU dressing effectively prevents seawater immersion, and significantly promotes seawater-immersed wound healing.

目的 建立枇杷花水提液中总酚的含量测定方法,优化总酚测定的最佳条件.方法 以没食子酸为对照品,在760nm处采用Folin-Ciocaheu法测定总酚的含量,考察福林-酚用量、Na2CO3溶液用量、显色时间等对测定的影响,并建立最佳测定条件.结果 Folin-Ciocaheu法测定枇杷花水提液中总酚,最佳福林-酚用量为3ml,最佳10％ Na2CO3溶液用量为6ml,最佳显色时间为50min,多酚质量浓度在0.4～ 3.2μg/ml范围内与吸光度线性关系良好,其回归方程为y=0.1419X+0.1427,R2=0.9974;加样回收率为96.19％,RSD为2.03％,该测定方法精密度、重复性和稳定性良好.结论 该方法简便易行,稳定性好,对提高枇杷花水提液的质量控制标准具有参考意义.