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Despite the long-term use and recent development of keratin materials, the mechanism of their solubilization is still not well understood beyond the breakage of disulfide bonds due to the complexit...

Accelerating and regulating collagen formation during wound healing repair is key issues for skin regeneration. Insulin can promote the healing of damaged skin by stimulating cellular migration and angiogenesis. Here, human hair keratin-conjugated insulin was synthesized to enhance full-thickness skin regeneration based on the excellent wound healing and hemostatic effects of keratin and the collagen deposition regulation ability of insulin. The insulin-conjugated keratin (Ins-K) was synthesized through the EDC/NHS reaction, which can supply a sustained release of insulin. The Ins-K hydrogel displayed similar water absorption, porosity and rheology properties to those of the keratin hydrogel. However, the Ins-K hydrogel shows a stronger hemostatic ability than the keratin hydrogel group, with a stronger wound healing effect found for the Ins-K hydrogel in the early regeneration stage (first 2 weeks) than for the keratin hydrogel treatment, resulting in smoother skin tissues at an excision section realized by regulating transforming growth factor β1 (TGF-β1) and hydroxyproline (HYP) expression. The results demonstrate that keratin promotes hemostasis and wound healing after insulin conjugation, which highlights the potential of keratin-based materials in tissue regeneration applications.

The setting principle of the power frequency distance protection is usually used for the setting of the time domain distance protection. However, it may result in operation failure or maloperation. So the setting method of the time domain distance protection based on the R-L model is proposed in this paper. The influencing factors of the measurement impedance calculation results of the time domain distance protection are analyzed. Then the protection action boundary is confirmed according to the directional impedance characteristic circle after considering various influencing factors and the margin. Finally, the setting method of the time domain distance protection is presented. The correctness of the proposed setting method is verified by ATP-EMTP simulation results. With this setting method, the sensitivity and reliability of time domain distance protection can be improved.

The role of surgery for most patients with spontaneous intracerebral haemorrhage (ICH) remains controversial due to the continuous occurrence of postoperative iron overload induced by low clot clearance rate. In this study, human hair keratose hydrogel (KG) loading with minocycline hydrochloride (MH) were prepared to reduce iron overload for the improvement of the postoperative functional recovery after ICH aspiration surgery. Hemoglobin-induced iron accumulation in rat primary neuronal culture was delayed by the adsorptive capacity of blank KG, while MH-loaded KG displayed a stronger and more thorough cytoprotective effect than blank KG due to the combined effect of absorptive action to iron and sustained release of the iron chelator. Moreover, high iron-chelating efficiency in the hematoma region supplied by MH-loaded KG significantly reduced dose strength of iron chelator. In situ injection of KG with different MH loadings (2, 20, and 200μg) into the hematoma region after aspiration surgery showed a stronger effect on the reduction of ICH-induced iron accumulation, edema, and neurological deficits in rats compared to the postoperative intraperitoneal administration of MH (approximately 15mg). These results suggested that the in situ KG not only could effectively reduce the ICH postoperative iron overload and improve the postoperative functional recovery via the iron adsorption and sustained release of MH, but also has great potential to reduce the systemic adverse effects by decreasing the dose strength of iron chelator.

The aims of this study were determining the co-induced effects of dietary Cadmium (Cd) and high intake of Molybdenum (Mo) on renal toxicity in ducks. 240 healthy 11-day-old ducks were randomly divided into 6 groups, which were treated with Mo or/and Cd at different doses added to the basal diet for 120 days. Ducks of control group were fed with basal diet, LMo and HMo groups were fed with 15mg/kg Mo and 100mg/kg Mo respectively; ducks of Cd group were provided with 4mg/kg Cd which was added into basal diet. Two combination groups were treated with 15mg/kg Mo+4mg/kg Cd and 100mg/kg Mo+4mg/kg Cd respectively. On days 30, 60, 90 and 120, the mRNA expression levels of inflammatory cytokines and contents of trace elements were detected. In addition, transmission electron microscopic examination was used for ultrastructural studies. The results indicated that the mRNA expression levels of tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), and cyclooxygenase-2 (COX-2) showed an upward tendency in treatment groups in comparison with control group, and in the later period of the experiment it showed a significant rise in joint groups compared with the Mo and Cd group (P0.01); the contents of copper (Cu) and iron (Fe) decreased in joint groups in the later period (P0.05) while the contents of Mo and Cd significantly increased (P0.01); zinc (Zn) and selenium (Se) concentration had a slight downtrend in treated groups, but showed no significant difference (P0.05). The ultrastructural analysis showed that kidney tissues were severely injured in joint groups on day 120. These results suggested that the combination of Mo and Cd could aggravate damages to the kidney. In addition, dietary of Mo or/and Cd caused the decrease of Cu, Fe, Zn, and Se contents, inflammatory response and pathological lesions whose mechanism is somehow linked with Mo and Cd deposition in kidney.

In recent years, favorable enhanced wound-healing properties and excellent biocompatibility of keratin derived from human hair have attracted considerable attention. Recombinant keratin proteins can be produced by recombinant DNA technology and have higher purity than extracted keratin. However, the wound-healing properties of recombinant keratin proteins remain unclear. Herein, two recombinant trichocyte keratins including human type I hair keratin 37 and human type II hair keratin 81 were expressed using a bacterial expression system, and recombinant keratin nanoparticles (RKNPs) were prepared via an ultrasonic dispersion method. The molecular weight, purity, and physicochemical properties of the recombinant keratin proteins and nanoparticles were assessed using gel electrophoresis, circular dichroism, mass spectrometry, and scanning electron microscope analyses. The RKNPs significantly enhanced cell proliferation and migration in vitro, and the treatment of dermal wounds in vivo with RKNPs resulted in improved wound healing associated with improved epithelialization, vascularization, and collagen deposition and remodeling. In addition, the in vivo biocompatibility test revealed no systemic toxicity. Overall, this work demonstrates that RKNPs are a promising candidate for enhanced wound healing, and this study opens up new prospects for the development of keratin biomaterials.

The chemical reaction mechanism of Ni/Al composites, referring to the exothermic mechanism and intermetallic-forming mechanism, is investigated by using molecular dynamics simulation. During the exothermic process, the influences of Ni/Al atomic ratios and crystallographic orientations on the exothermic reaction are systematically investigated. The exothermic mechanism can be explained by the atomic diffusion that increases the quantity of Ni–Al chemical bonds. There are two pathways to form the intermetallic phase during the chemical reaction. One is the atomic diffusion that forms the B2 NiAl phase at the interface. The other way is quenching the sample to the room temperature, but the type of intermetallic phases depends on the Ni/Al atomic ratio and ignition temperature.

Keratins derived from human hair possess excellent wound healing qualities. However, their functional contribution to this process is poorly understood. In this study, the regulatory function of human hair keratins in wound healing is investigated using proteomic analysis by dividing keratins into different groups based on their molecular weight distributions: low molecular weight keratins (LMWK, 10-30 kDa), medium molecular weight keratins (MMWK, 30-50 kDa), and high molecular weight keratins (HMWK, >50 kDa). Keratin hydrogels with different molecular weights exhibit various morphologies, rheological properties, degradation rates, and wound healing activities. Using proteomic analysis, LMWK and HMWK hydrogels exhibit a stronger regulatory ability for wound healing at days 1 and 7, respectively. The major functions of LMWK during wound healing are regulation of cells communication and function. In contrast, proteins associated with energy metabolism are significantly expressed after HMWK hydrogel treatment at day 1, and these play an important role in cellular growth and reactive oxygen species scavenging at day 7. These results demonstrate that the wound healing qualities of human hair keratins are influenced by their molecular weight distribution, and the proteomic analysis sheds new light on the regulatory function of human hair keratins during wound healing.

Additional file 1: Figure S1. The schematic diagram of the ultrasonic system for the synthesis of KNPs. Figure S2. The time-dependent changes in the average size of KNPs within 7 days. Figure S3. H&E histological examination of the main organs after oral administration of the KNP-3 for 7 days (original magnification 100 Ă ).

Keratins are highly attractive for wound healing due to their inherent bioactivity, biocompatibility and physical properties. However, nearly all wound healing studies have focused on human hair keratins, and the wound-repair effects and in vivo biocompatibilities of feather keratins are not clear. Feather keratins are derived from chicken feathers, which are considered to be the major waste in the poultry industry, and the quality of feather keratin is easier to control than that of human hair keratin due to human hair perming and colouring-dyeing. Thus, we extracted keratins from chicken feathers, and a feather keratin hydrogel was then prepared and used to test the in vivo wound-healing properties and biocompatibility. The results indicated that feather keratins displayed wound-healing and biodegradation properties similar to those of human hair keratins and were also highly compatible with those of the tissue and devoid of immunogenicity and systematic toxicity. Collectively, these results suggested that feather keratin hydrogel could be used for biomedical applications, particularly effective wound healing.

Background Stroke remains the second commonest cause of death and leading cause of adult disability worldwide. Ischemic events account for nearly 85% of all strokes, and hemorrhages account for nearly 15%. Stroke intervention and recovery have been identified as the important factors in the functional outcome of patients with completed stroke. However, the only FDA approved treatment for ischemic strokes is tissue plasminogen activator, and no effective targeted therapy for hemorrhagic stroke exists yet. Methods The goal of this work is to review the brain drug delivery systems (BDDS) used for stroke intervention and recovery. Results Many novel BDDS have been developed for the use of stroke intervention and recovery, including nanoparticles, hydrogels, fibers, liposomes, and so on, which could improve the permeability of blood-brainbarrier (BBB), short half-life, stability in vivo, and reduce adverse effects of drugs. Conclusion Combined with new drug targets in the treatment of stroke, BDDS will provide more effective therapeutics for stroke intervention and recovery.

To evaluate the effects of dietary Molybdenum (Mo) or/and Cadmium (Cd) on trace elements and the mRNA expression levels of heat shock proteins (Hsps) and inflammatory cytokines in duck livers. 240 healthy 11-day-old ducks were randomly divided into six groups with 40 ducks in each group, which were treated with Mo or/and Cd at different doses on the basal diet for 120 days. On days 30, 60, 90 and 120, 10 birds in each group were randomly selected and euthanized and then the livers were collected to determine the contents of Mo, Cd, copper (Cu), iron (Fe), zine (Zn), Selenium (Se) and the mRNA expression levels of Hsps, inflammatory cytokines. In addition, liver tissues at 120 days were subjected to histopathological analysis with the optical microscope. The results showed that the mRNA expression of Hsp60, Hsp70, Hsp90, tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), and cyclooxygenase-2 (COX-2) were significantly (P

The peptide-based delivery system constitutes a potent approach to overcome the limitations of drug delivery in vitro and in vivo. We recently proposed a novel peptide RDP, which enables brain-targeting delivery of proteins into neuronal cells. Here we investigate the possible internalization mechanism of RDP, and identify the therapeutic effects of functional proteins when linked with RDP in brain disease.The RDP fusion proteins are produced through recombinant DNA technology, and cell culture is used to investigate the uptake mechanism of RDP and its fusion protein. Experimental Parkinson's disease (PD) model is prepared in mice by intra-striatal injection of 6-hydroxydopamine, and is tested by apomorphine- and amphetamine-induced rotation.The results suggest that the possible route for RDP cellular uptake might involve GABA receptor-dependent, clathrin-mediated endocytosis pathway. Additionally, the conjugate of RDP and glial cell-derived neurotrophic factor (GDNF) exhibits the neuroprotective effect in experimental PD animals, including reduction of apomorphine- and amphetamine-induced rotation following toxin administration.RDP may become an effective tool for the targeted delivery of proteins into brain for disease treatment.

It is an efficient approach of nonlinear correction for sensors by fitting curves to data, but it is difficult to fit curve with a single model for the thermocouple vacuum sensor, since its characteristic is very complex. A novel method of curve fitting based on multiple support vector regression (MSVR) is proposed. The sample space are divided into several sub-spaces, nonlinear mapping is established in each sub-space by using support vector regressions (SVR), each SVR may has parameters different from the others to approximate the sensor characteristic in corresponding partial space, combining the outputs of all the SVRs the complete characteristic of the sensor is achieved. The proposed approach was applied to fit the characteristic curve for the thermocouple vacuum sensor, the experiment results demonstrate the effectiveness and practicability of the proposed method.

Contract Net is an important model based on competition mechanism to solve the collaborative problems, but exits many shortages. In this paper a negotiation strategy of multi-Agent based on extended contract net is presented to reduce the communication and negotiation time and improve the efficiency. Agent mind parameters and buffer pool are introduced to support the extended contract net. So the negotiation quality will be improved and the system will be more adaptive and flexible.

A new multi-view model based on UML is proposed in this paper, that is "6 +1" view model. The model describes the architecture of a system from seven perspectives which contains scenario, concept view, framework view, data view, process view, component view and deployment view. And the model is applied to describe the architecture of the steel base management system to verify its feasibility and usability. The practice indicates that the new multi-view model is an efficient and effective method in object-oriented modeling.