Hydrogels for neuroprotection and functional rewiring: a new era for brain engineering

The neurological devastation of neurodegenerative and cerebrovascular diseases reinforces our perseverance to find advanced treatments to deal with these fatal pathologies.High-performance preclinical results have failed at clinical level,as it has been the case for a wide variety of neuroprotective agents and cell-based therapies employed to treat high prevalent brain pathologies such as stroke,Alzheimer’s and Parkinson’s diseases.An unquestionable reality is the current absence of effective therapies to neuroprotect the brain,to arrest neurodegeneration and rewire the impaired brain circuits.Part of the problem might arise from the lack of adequate in vitro and in vivo models and that most of the underlying pathophysiological mechanisms are not yet clarified.Another contributing factor is the lack of efficient systems to sustain drug release at therapeutic concentrations and enhance the survival and function of grafted cells in transplantation procedures.For medical applications the use of biomaterials of different compositions and formats has experienced a boom in the last decades.Although the greater complexity of central nervous system has probably conditioned their extensive use with respect to other organs,the number of biomaterials-based applications to treat the injured brain or in the process of being damaged has grown exponentially.Hydrogel-based biomaterials have constituted a turning point in the treatment of cerebral disorders using a new form of advanced therapy.Hydrogels show mechanical properties in the range of cerebral tissue resulting very suitable for local implantation of drugs and cells.It is also possible to fabricate three-dimensional hydrogel constructs with adaptable mesh size to facilitate axonal guidance and elongation.Along this article,we review the current trends in this area highlighting the positive impact of hydrogel-based biomaterials over the exhaustive control of drug delivery,cell engraftment and axonal reinnervation in brain pathologies.

Providing a Therapeutic Scheduling for HIV Infected Individuals with Genetic Algorithms Using a Cellular Automata Model of HIV Infection in the Peripheral Blood Stream

The aim of this study is to develop two-dimensional cellular automata model of HIV infection that depicts the dynamics involved in the interactions between acquired immune system and HIV infection in the peripheral blood stream. The appropriate biological rules of cellular automata model have been extracted from expert knowledge and the model has been simulated with determined initial conditions. Obtained results have been validated through comparing with the accepted AIDS reference curve. The new rules and states were added to the proposed model to show the effects of applying combined antiretroviral therapy. Our results showed that by applying RTI and PI drugs with maximum drug effectiveness, comparing with cases in which no treatment was applied, the steady state concentrations of healthy (infected) CD4+T cells were increased (decreased) 53% (41%). Also, the use of cART with maximum drug effectiveness led to a 69% reduction in the steady state level of viral load. At this time, obtained results have been validated through comparing with available clinical data. Our results showed good agreement with both reference curve and the clinical data. In the second phase of this study, by applying genetic algorithms, a therapeutic schedule has been provided that its use, while maintaining the quality of the treatment, leads to a 47% reduction in both drug dosage and the side effects of antiretroviral drugs.

WavEnhancer: Unifying Wavelet and Transformer for Image Enhancement

Image enhancement is a widely used technique in digital image processing that aims to improve image aesthetics and visual quality. However, traditional methods of enhancement based on pixel-level or global-level modifications have limited effectiveness. Recently, as learning-based techniques gain popularity, various studies are now focusing on utilizing networks for image enhancement. However, these techniques often fail to optimize image frequency domains. This study addresses this gap by introducing a transformer-based model for improving images in the wavelet domain. The proposed model refines various frequency bands of an image and prioritizes local details and high-level features. Consequently, the proposed technique produces superior enhancement results. The proposed model’s performance was assessed through comprehensive benchmark evaluations, and the results suggest it outperforms the state-of-the-art techniques.

Percutaneous assist devices in acute myocardial infarction with cardiogenic shock: Review, meta-analysis

AIM: To assess the impact of percutaneous cardiac support in cardiogenic shock(CS) complicating acute myocardial infarction(AMI), treated with percutaneous coronary intervention. METHODS: We selected all of the studies published from January 1st, 1997 to May 15 st, 2015 that compared the following percutaneous mechanical support in patients with CS due to AMI undergoing myocardial revascularization:(1) intra-aortic balloon pump(IABP) vs Medical therapy;(2) percutaneous left ventricular assist devices(PLVADs) vs IABP;(3) complete extracorporeal life support with extracorporeal membrane oxygenation(ECMO) plus IABP vs IABP alone; and(4) ECMO plus IABP vs ECMO alone, in patients with AMI and CS undergoing myocardial revascularization. We evaluated the impact of the support devices on primary and secondary endpoints. Primary endpoint was the inhospital mortality due to any cause during the same hospital stay and secondary endpoint late mortality at 6-12 moof follow-up. RESULTS: One thousand two hundred and seventytwo studies met the initial screening criteria. After detailed review, only 30 were selected. There were 6 eligible randomized controlled trials and 24 eligible observational studies totaling 15799 patients. We found that the inhospital mortality was:(1) significantly higher with IABP support vs medical therapy(RR = +15%, P = 0.0002);(2) was higher, although not significantly, with PLVADs compared to IABP(RR = +14%, P = 0.21); and(3) significantly lower in patients treated with ECMO plus IABP vs IABP(RR =-44%, P = 0.0008) or ECMO(RR =-20%, P = 0.006) alone. In addition, Trial Sequential Analysis showed that in the comparison of IABP vs medical therapy, the sample size was adequate to demonstrate a significant increase in risk due to IABP. CONCLUSION: Inhospital mortality was significantly higher with IABP vs medical therapy. PLVADs did not reduce early mortality. ECMO plus IABP significantly reduced inhospital mortality compared to IABP.