Supporting wound healing by mesenchymal stem cells (MSCs) therapy in combination with scaffold, hydrogel, and matrix; State of the art.

Non-healing wounds impose a huge annual cost on the survival of different countries and large populations in the world. Wound healing is a complex and multi-step process, the speed and quality of which can be changed by various factors. To promote wound healing, compounds such as platelet-rich plasma, growth factors, platelet lysate, scaffolds, matrix, hydrogel, and cell therapy, in particular, with mesenchymal stem cells (MSCs) are suggested. Nowadays, the use of MSCs has attracted a lot of attention. These cells can induce their effect by direct effect and secretion of exosomes. On the other hand, scaffolds, matrix, and hydrogels provide suitable conditions for wound healing and the growth, proliferation, differentiation, and secretion of cells. In addition to generating suitable conditions for wound healing, the combination of biomaterials and MSCs increases the function of these cells at the site of injury by favoring their survival, proliferation, differentiation, and paracrine activity. In addition, other compounds such as glycol, sodium alginate/collagen hydrogel, chitosan, peptide, timolol, and poly(vinyl) alcohol can be used along with these treatments to increase the effectiveness of treatments in wound healing. In this review article, we take a glimpse into the merging scaffolds, hydrogels, and matrix application with MSCs therapy to favor wound healing.

Multiobjective optimization of a hybrid electricity generation system based on waste energy of internal combustion engine and solar system for sustainable environment.

In recent years, the interest in generating power through hybrid power generation systems has increased. In this study, a hybrid power generation system including an internal combustion engine (ICE) and a solar system based on flat plate collectors to generate electricity is investigated. To benefit from the thermal energy absorbed by solar collectors, an organic Rankine cycle (ORC) is considered. In addition to the solar energy absorbed by the collectors, the heat source of the ORC is the wasted heat through exhaust gases and the cooling system of the ICE. A two-pressure configuration for ORC is proposed for optimal heat absorption from the three available heat sources. The proposed system is installed to produce power with a capacity of 10 kW. A bi-objective function optimization process is carried out to design this system. The objective of the optimization process is to minimize the total cost rate and maximize the exergy efficiency of the system. The design variables of the present problem include the ICE rated power, the number of solar flat plate collectors (SFPC), the pressure of the high-pressure (HP) and low-pressure (LP) stage of the ORC, the degree of superheating of the HP and LP stage of the ORC, and its condenser pressure. Finally, it is observed among the design variables the most impact on total cost and exergy efficiency is related to the ICE rated power and the number of SFPCs.

Sexual behavior, HPV knowledge, and association with head and neck cancer among a high-risk group.

OBJECTIVES: To understand knowledge of HPV, its association with head and neck cancer (HNC), and source of knowledge in a high-risk population. MATERIALS AND METHODS: A cross-sectional survey was conducted among attendees at a Drag Racing event in East St. Louis in 2013. RESULTS: Only 29.9% knew that HPV definitely increases the risk of developing HNC, 42.4% thought HPV was same as HIV, and only 25.1% received HPV information from a healthcare practitioner. Participants that thought number of sexual partners did not increase risk of developing HPV were more likely to have low knowledge scores (r=.74, p<.001). There were significant associations between HNC knowledge, number of sexual partners, age at initial coitus, and risk perception; and those who did not think having more sexual partner increases the chance of developing HPV infection were 33times more likely to have lower knowledge of the association between HPV and HNC (OR=33.27; 95% CI: 16.34, 67.74). CONCLUSIONS: Knowledge of HPV and its association with head and neck cancer has significant gaps in this population, with a large number of the population accessing HPV information from sources other than a healthcare provider.

HERV-K-specific T cells eliminate diverse HIV-1/2 and SIV primary isolates.

The genetic diversity of HIV-1 represents a major challenge in vaccine development. In this study, we establish a rationale for eliminating HIV-1-infected cells by targeting cellular immune responses against stable human endogenous retroviral (HERV) antigens. HERV DNA sequences in the human genome represent the remnants of ancient infectious retroviruses. We show that the infection of CD4+ T cells with HIV-1 resulted in transcription of the HML-2 lineage of HERV type K [HERV-K(HML-2)] and the expression of Gag and Env proteins. HERV-K(HML-2)-specific CD8+ T cells obtained from HIV-1-infected human subjects responded to HIV-1-infected cells in a Vif-dependent manner in vitro. Consistent with the proposed mode of action, a HERV-K(HML-2)-specific CD8+ T cell clone exhibited comprehensive elimination of cells infected with a panel of globally diverse HIV-1, HIV-2, and SIV isolates in vitro. We identified a second T cell response that exhibited cross-reactivity between homologous HIV-1-Pol and HERV-K(HML-2)-Pol determinants, raising the possibility that homology between HIV-1 and HERVs plays a role in shaping, and perhaps enhancing, the T cell response to HIV-1. This justifies the consideration of HERV-K(HML-2)-specific and cross-reactive T cell responses in the natural control of HIV-1 infection and for exploring HERV-K(HML-2)-targeted HIV-1 vaccines and immunotherapeutics.

Human endogenous retrovirus K(HML-2) Gag- and Env-specific T-cell responses are infrequently detected in HIV-1-infected subjects using standard peptide matrix-based screening.

T-cell responses to human endogenous retrovirus (HERV) K(HML-2) Gag and Env were mapped in HIV-1-infected subjects using 15 mer peptides. Small peptide pools and high concentrations were used to maximize sensitivity. In the 23 subjects studied, only three bona fide HERV-K(HML-2)-specific responses were detected. At these high peptide concentrations, we detected false-positive responses, three of which were mapped to an HIV-1 Gag peptide contaminant. Thus, HERV-K(HML-2) Gag- and Env-specific T-cell responses are infrequently detected by 15 mer peptide mapping.