A Novel Conductive Antibacterial Nanocomposite Hydrogel Dressing for Healing of Severely Infected Wounds.

Wound infections are serious medical complications that can endanger human health. Latest researches show that conductive composite materials may make endogenous/exogenous electrical stimulation more effective, guide/comb cell migration to the wound, and subsequently promote wound healing. To accelerate infected wound healing, a novel medical silver nanoparticle-doped conductive polymer-based hydrogel system (Ag NPs/CPH) dressing with good conductivity, biocompatibility, and mechanical and antibacterial properties was fabricated. For the hydrogel dressing, Ag NPs/CPH, polyvinyl alcohol (PVA), and gelatin were used as the host matrix materials, and phytic acid (PA) was used as the cross-linking agent to introduce conductive polyaniline into the matrix, with antibacterial Ag NPs loaded via impregnation. After a series of analyses, the material containing 5 wt% of PVA by concentration, 1.5 wt% gelatin, 600 µL of AN reactive volume, and 600 µL of PA reactive volume was chosen for Ag NPs/CPH preparation. XPS and FTIR analysis had been further used to characterize the composition of the prepared Ag NPs/CPH. The test on the swelling property showed that the hydrogels had abundant pores with good water absorption (≈140% within 12 h). They can be loaded and continuously release Ag NPs. Thus, the prepared Ag NPs/CPH showed excellent antibacterial property with increasing duration of immersion of Ag NPs. Additionally, to evaluate in vivo safety, CCK-8 experiments of HaCat, LO2 and 293T cells were treated with different concentrations of the Ag NPs/CPH hydrogel soaking solution. The experimental results showed the Ag NPs/CPH had no significant inhibitory effect on any of the cells. Finally, an innovative infection and inflammation model was designed to evaluate the prepared Ag NPs/CPH hydrogel dressing for the treatment of severely infected wounds. The results showed that even when infected with bacteria for long periods of time (more than 20 h), the proposed conductive antibacterial hydrogel could treat severely infected wounds.

Activin A affects feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish (Danio rerio) larvae.

Activin A belongs to the superfamily of transforming growth factor-ß and plays an important role in hormone regulation and tissue development. However, few research studies have been conducted on the effect of activin A on feeding organs in fish. In this study, the zebrafish (Danio rerio) larvae were treated with 1 ng ml-1 activin A for 8 days continuously. The haematoxylin and eosin (H&E) staining section results revealed that the transverse inner diameter of the pharynx and oesophagus significantly increased on the third and eighth days after treatment compared with the control group (P < 0.05). On the eighth day, the cross-sectional area of the pharyngeal muscle increased by 8638 µm2 compared to the control group (P < 0.05). The RNA in situ hybridization results also showed that the expression of skeletal muscle-specific genes (myog and myod) was significantly increased in pharyngeal muscle on the eighth day. Furthermore, the qRT-PCR results showed the expression of gh gene was significantly increased on the eighth day (P < 0.05). At the same time, more larvae in activin A group were able to feed larger brine shrimp (Artemia) than in the control group on the eighth day. In conclusion, activin A could affect feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish larvae. This study is the first to report that the development of the pharynx and oesophagus can directly affect food intake in fish larvae, which provides a theoretical basis for the study of food intake of fish at an early stage.

Growth and Metabolic Response of Chinese Perch to Different Dietary Protein-to-Energy Ratios in Artificial Diets.

The effect of dietary nutrients on novel farm species has always garnered wide research and economic interest. Chinese perch, an economically important carnivorous fish, accepts an artificial diet after taming, so it is essential to evaluate and optimize the nutritional and metabolic demands of this species. However, little is known about the effect of an artificial diet on the growth and metabolism of Chinese perch. Therefore, the present study evaluated the growth and metabolic responses of Chinese perch to experimental diets with different dietary protein/energy (P/E) ratios. Five isoenergetic diets (18 kJ/g) with graded levels of P/E ratios of 30.58, 33.22, 35.90, 38.6, and 41.35 mg/kJ (named A, B, C, D, and E) were formulated. A total of 225 Chinese perch (64.89 ± 0.28 g) were divided into five groups (triplicate tanks for each group), distributed into 15 (350 L) fiberglass tanks, and fed twice a day at 4% of fish wet body weight with the respective P/E ratio diets for 10 weeks. Compared with the other groups, Chinese perch in Group C showed significantly improved growth performance, weight gain (WG), specific growth rate (SGR), viscerosomatic index (VSI), hepatosomatic index (HSI), intraperitoneal fat (IPF), feed utilization, feed intake (FI), feed conversion ratio (FCR), protein efficiency ratio (PER), protein retention efficiency (PRE), energy retention efficiency (ERE), and feed efficiency (FE) as well as whole-body, muscle, and liver composition. Chinese perch in Group A, on the other hand, had the lowest growth performance, feed utilization, and body composition compared with the other groups. The activities of nitrogen metabolism-related enzymes (alanine aminotransferase (ALT), aspartate aminotransferase (AST) glutamate dehydrogenase (GDH), and adenosine 5'-monophosphate deaminase (AMPD)) as well as the mRNA expression of the GDH and AMPD genes were significantly lower than those in the other groups. Similarly, the expression of NPY and AgRp were significantly higher in Group C compared with the other groups. However, the gene expression of CART and POMC was not affected by the dietary P/E ratios. In Group A, the expression of mTOR, S6K, and 4EBP1 was significantly lower and that of AMPK, LKB1, and eEF2 was significantly higher when compared with the other groups. Biochemical analysis of blood showed that ALT, AST, total protein (TP), alkaline phosphatase (ALP), glucose (GLU), blood urea nitrogen (BUN), and triglyceride (TG) levels were also affected by the dietary P/E ratio. From our results, we concluded that Chinese perch growth performance and nutrient metabolism were significantly affected by the P/E ratio of the artificial diet. Second-order polynomial regression analysis revealed that Chinese perch growth performance was optimal at a P/E ratio of 37.98 in the artificial diet.

The correlation between plasma tissue factor and interleukin 18 and their significance in patients with acute coronary syndrome.

Studies suggested that the activation of the coagulation system and inflammation mutually may reinforce each other in some cases. In this study, we test the plasma tissue factor (TF) and interleukin 18 in patients with coronary heart disease (CHD) before and after treatment and aim to determine whether this relationship exists in patients with CHD. The levels of plasma TF and IL-18 from 118 patients with CHD were determined by enzyme-linked immunosorbent assay. One hundred and eighteen patients were divided into acute coronary syndrome (ACS) group (61 cases) and stable angina pectoris group (51 cases). Upon admission, patients with ACS showed significantly higher levels of plasma TF and interleukin 18 compared with those having stable angina (P < 0.01), and the levels decreased after treatment; levels of plasma TF and interleukin 18 of patients with ACS were closely and positively correlated (r = 0.74, P < 0.01); after 7 days of treatment, the correlation decreased (r = 0.53, P > 0.05); and after 1 month of treatment, no significant correlation can be detected between the two (r = 0.18, P > 0.05). The results suggest that levels of plasma TF and interleukin 18 are significantly increased in patients with ACS, and there is significant correlation between the two, indicating an interaction between inflammation and coagulation in patients with ACS and an important role of these two in the occurrence and development of such disease.