Preparation of aminated fish scale collagen and oxidized sodium alginate hybrid hydrogel for enhanced full-thickness wound healing.

Acute full-thickness wounds require a more extended healing period, thus increasing the risk of infection. Severe infection frequently resulted in wound ulceration, necrosis, and even life-threatening complications. Here, a hybrid hydrogel comprising aminated collagen (AC), oxidized sodium alginate (OSA), and antimicrobial peptides (polymyxin B sulfate and bacitracin) was developed to enhance full-thickness wound healing. The AC with low immunogenicity and high biocompatibility was made from marine fish scales, which are eco-friendly, low-cost, and sustainable. The cross-linked hydrogel was formed by a Schiff base reaction without any catalysts and additional procedures. As expected, the presented hybrid hydrogel can effectively against E. coli and S. aureus, as well as promote cell growth and angiogenesis in vitro. In addition, the hydrogel can promote full-thickness wound healing in a rat model through accelerating reepithelialization, collagen deposition, and angiogenesis. Our work demonstrated that the hybrid hydrogel has promising applications in the field of wound healing, which would prompt the utilization of marine fish resources during food processing.

Preparation and evaluation of a Rubropunctatin-loaded liposome anticancer drug carrier.

Rubropunctatin is a naturally occurring constituent of polyketide compounds that has great potential in the development of cancer-assisted chemotherapy. However, it has certain shortcomings such as water insolubility and photo instability that limit its clinical application. In this study, we constructed a Rubropunctatin-loaded liposome (R-Liposome) anticancer drug carrier for the first time. The results indicate that R-Liposome is water soluble, has spherical morphology, great homogeneity and dispersibility with high encapsulation efficiency (EE%, 90 ± 3.5%) and loading rate (LR%, 5.60 ± 2.5%) values. Moreover, the carrier improves the photostability, storage and pH stabilities of Rubropunctatin. The R-Liposome also prolongs the release of Rubropunctatin, enhances the anticancer activity of Rubropunctatin and encourages the mechanism of Rubropunctatin to promote apoptosis. Therefore, liposomal nanoparticles have great potential as drug delivery vehicles of Rubropunctatin for cancer treatment.

Evaluation of behavioral profiles in mice fed with milk supplemented diets derived from human lactoferrin gene-modified cows.

To date, many safety assessments of genetically modified (GM) food have been done, but there was still considerable skepticism about the safety of genetic modified foods because no study could be designed to discover all of the potential effects. Since behavioral endpoints could provide one of the most sensitive strategies to reveal subtle functional deficits. In the present study, behavioral profiles in mice fed with milk derived from human lactoferrin gene-modified cows were investigated to enrich the toxicological data of GM food. Conventional milk and GM milk were added to diets at a proportion of 7.5%, 15% and 30%(w/w). After the mice consuming different diets for 30 days, a battery of behavioral tests were conducted to evaluate motor, sensory and cognitive functions. No significant differences were observed in spontaneous activity, grip strength and nociception between the treatment groups. And animals of different groups exhibited similar performance in rotarod, dark box, step-down and MORRIS water maze task. The study suggested that mice fed with conventional milk or human lactoferrin gene-modified milk had similar motor, sensory and cognitive functions.

Safety assessment of meat from transgenic cattle by 90-day feeding study in rats.

The study was carried out to evaluate the subchronic toxicity of meat derived from human lactoferrin gene-modified cattle in male and female Wistar rats. Rats were fed 5% or 10% transgenic meat diet, 5% or 10% conventional meat diet, or AIN93G diet for 90 days. During the study, body weight and food consumption were weighed weekly and clinical observations were conducted daily. At the end of the study, urinary examination, hematology and blood biochemistry examination, macroscopic and microscopic examinations were performed. There were no biologically significant differences in these factors between the rat groups fed transgenic meat diet and conventional meat diet. Therefore, the present 90-day rodent feeding study suggests that meat derived from the transgenic cattle is equivalent to meat from conventional cattle in use as dietary supplements.

[Study on dermal absorption of Imidacloprid in vitro].

OBJECTIVE: The dermal absorption of Imidacloprid was studied to understand the effects of concentrations and skin reservoir on pesticide risk assessment in in vitro absorption studies. METHODS: By using Franz diffusion cell and the transdermal barrier of viable Wistar rat abdomen skin or frozen ones, the imidacloprid content in the receptor fluid and skin was determined by LC/MS/MS method, and the absorption effects were compared between two concentrations of Imidacloprid solutions and two types of skin, respectively. RESULTS: All percentages reported are % of applied dose. In vitro studies using viable skin, the Imidacloprid content in the receptor fluid of high and low concentration was 6.8%, 6.6% respectively; and 10.7%, 1.3% in skin, thus total absorption was 17.5% and 7.9%. And in vitro studies using both viable and frozen skin under the same concentration circumstances, the Imidacloprid content in the receptor fluid of viable and frozen skin was 6.6% and 0.7% respectively, in skin was 1.3% and 10.7%, and total absorption was 7.9% and 11.4%. CONCLUSION: Comparison of these in vitro results showed that either concentrations or skin reservoir had an effect on the dermal absorption. During 6h exposure, the high concentration in viable skin had the maximum dermal absorption value, which was the worst-case exposure estimate, also the best single estimate for pesticide risk assessment.

[Study on sub-chronic toxicity of powered milk containing transgenic human alpha-lactalbumin].

OBJECTIVE: To investigate the potential toxic or adverse effect of transgenic human alpha-lactalbumin powered milk on rats. METHODS: Weanling Wistar rats were randomly divided into seven groups according the weight: three transgenic milk powder (T) groups, three non-transgenic milk powder (N) groups and the control (C) group. The diets of T groups contain 15%, 30% and 60% transgenic human alpha-lactalbumin milk powder. The diets of N groups contain 15%, 30% and 60% non-transgenic human alpha-lactalbumin milk powder for 90 days. The diet of C group contains only basic feed. Haematological and biochemical parameters was measured during the study (at 45th and 90th of the experiment). At the end of the 90th day, organ tissues analysis was performed. RESULTS: There were no transgenic human alpha-lactalbumin related adverse effects on the body weight, food intake, food consumption, hematology,serum biochemistry, as well as histopathology. CONCLUSION: There were no signs of toxic and adverse effects for transgenic human alpha-lactalbumin powdered milk on rats.

[Anaphylactic reactions in WZS minipig orally induced by glycinin].

OBJECTIVE: To explore the suitable dosage and observation period of anaphylactic reactions in WZS minipigs induced by glycinin (11S). METHODS: Twelve 45-day-old WZS minipigs were randomly divided into three groups (control group, 4% 11S group and 8% 11S group, n = 4), which were respectively orally sensitized (0 - 10d) and orally challenged (16 - 18d, 31d) with diets containing 0%, 4% 11S or 8% 11S soybean proteins to induce anaphylactic reactions. Clinical symptoms, skin prick reactions, serum IgG, serum IgE, histamine, mast cell in the small intestine were observed or measured. RESULTS: Diarrhea and positive skin prick reactions at different degrees were observed in 11S groups. Compared with the control group, serum IgG, IgE and histamine levels of 4% 11S group at 19d and 32d were significantly higher (P < 0.05), and reached the peak when 11S groups were orally challenged at 19d. The jejunum histamine level was negatively correlated with the mast cell numbers in the jejunum mucosa and sub-mucosa (P < 0.05). Compared with the control, the mast cell number in the jejunum sub-mucosa of 4% 11S group was decreased (P < 0.05). CONCLUSION: The WZS minipig allergic reaction orally induced by glycinin could be type I hypersensitivity mediated by IgE, reaction induced by 4% dosage glycinin could be more strong than that of 8% dosage, and stimulating phase could be a suitable observation period for anaphylactic reactions which could be related with the activation of mast cells in the small intestine.