Electrospinning for Drug Delivery Systems: Drug Incorporation Techniques

Electrospinning is a very versatile techniqueused for many purposes, such as tissue engineering, textiles, air and water treatment filter, solar cells, and drug delivery systems, among others. This method is cheap, easy to handle, reproducible when ambient parameters are controlled, and can be used for many formulations. The objective of this review is to enlist and emphasize the advantages and disadvantages of different methods for incorporating therapeutic drugs in a drug delivery system with electrospinning. The importance of the research to create new and innovative drug carriers is high, because of their efficiency of transporting the bioactive agent to the target zone, avoiding secondary effects in the body. Nanofibers and nanoparticles have become an important strategy in pharmacology due to their physicochemical and biocompatible properties useful for this purpose. Among the techniques compared are blending coaxial, emulsion and surface modification electrospinning, followed by electrospray and coaxial electrospray. The present review concludes that every technique has advantages and disadvantages and, not all drugs can be loaded with any method, the strategy used will depend on the drug’s physicochemical properties, target zone, polymeric characteristics, and required drug release rate. This chapter will serve as a starting point for when to choose one of the drug incorporation techniques mentioned

Novel Drug Carries: Properties and Applications

Conventional drug administration has several issues and challenges such as full doses absorption and efficient targeting, some generate undesirable secondary effects and promote damage to organs and tissues such as the liver and kidneys, and others trigger inflammation and immune responses. Hence, drug carriers help to promote drug absorption, enhance targeting, avoid or decrease secondary effects, possess the ability to camouflage drugs from immune cells and proteins, and permit controlled release to provide prolonged drug delivery to maintain its blood concentration within therapeutic limits. Drug carriers have gained importance thanks to their various properties such as biocompatibility, biodegradability, mechanical properties, and high surface area, among others. Drug carriers are getting crucial to avoid or diminish secondary effects and improve the targeting of the administered drugs incrementing their effectiveness. Hence, this book chapter aims to introduce some drug carriers (electrospun nanofibers, aptamers, micelles, and liposomes), describing the properties and polymers used. It is observed that fast dissolving administration is the most recommended strategy for the use of drug carriers, where more evident therapeutics benefits can be appreciated

Gelatin and Collagen Nanofiber Scaffolds for Tissue Engineering

One of the main complications that can present a person with second and third degree burns is the possibility of being infected by opportunistic bacteria or viruses that are present in the environment. Nowadays, the majority of the burn injuries are treated with conventional gauze, which involves a high probability of infection and pain for the patient being treated with this method. In order to obtain low-cost scaffolds, natural and abundant polymers were used such as gelatin (GEL) and collagen (COL). The GEL functions as a base scaffold, stable and flexible, and also biocompatible because it is a byproduct of the partial hydrolysis of COL, which is an indispensable component for the stability of the cell membrane and it is present in great extent in the human epithelium

Biosensors to diagnose Chagas disease: A review

International audienceChagas disease (CD), which mostly affects underprivileged people, has turned into one 9 of Latin America's main public health problems. Prevention of the disease requires early diagnosis, 10 initiation of therapy, and regular blood monitoring of the infected individual. However, the majority 11 of the infections go undiagnosed because of general mild symptoms and lack of access to medical 12 care. Therefore, more affordable and accessible detection technologies capable of providing early 13 diagnosis and parasite load measurements in settings where CD is prevalent are needed to enable 14 enhanced intervention strategies. This review discusses currently available detection technologies 15 and emerging biosensing technologies for a future application to CD. Even if biosensing 16 technologies still require further research efforts to develop portable systems, we arrive to the 17 conclusion that biosensors could improve diagnosis and the patients' treatment follow-up, in terms 18 of rapidity, small sample volume, high integration, ease of use, real-time and low cost detection 19 compared to current conventional technologies. 2

Gene Copy Number Quantification of SHOX , VAMP7 , and SRY for the Detection of Sex Chromosome Aneuploidies in Neonates

Aims: To explore the feasibility of detecting sex chromosome aneuploidies (SCAs) by means of gene copy number quantification of short stature homeobox (SHOX), vesicle-associated membrane protein 7 (VAMP7), and SRY in newborns. Materials and Methods: Gene doses of SHOX, VAMP7, and SRY were determined by quantitative polymerase chain reaction (qPCR) using DNA obtained from dried blood samples from newborns. Relative quantification values were obtained. An aneuploidy profile was established according to cutoff values. Samples with ≥2 gene doses (out of range) were reanalyzed, and those with aneuploidy profiles were confirmed by karyotyping. Sensitivity, specificity, and positive and negative predictive values were obtained. Results: A total of 10,033 samples were collected (4945 females and 5088 males). Of 244 (2.43%) samples with ≥2 gene doses that were retested, 20 cases were confirmed. The overall incidence of SCAs was 1 in 500 live newborns. There were six cases of Turner syndrome (1/824), 3 cases of XXX (1/1648), 7 cases of Klinefelter syndrome (1/726), and 4 cases of of XYY (1/1272). The sensitivity was 0.952 (95.24%), specificity of 0.975 (97.56%), positive predictive value of 0.909 (90.91%), and negative predictive value of 0.987 (98.77%). Conclusions: Gene copy number analyses of VAMP7, SHOX, and SRY genes by qPCR from blood samples spotted onto filter paper is a highly reliable method for the early detection of male and female SCAs

Effect of mineral aggregates and chemical admixtures as internal curing agents on the mechanical properties and durability of highperformance concrete

In the present work, the effect of mineral aggregates (pumice stone and expanded clay aggregates) and chemical admixtures (superplasticizers and shrinkage reducing additives) as an alternative internal curing technique was investigated, to improve the properties of highperformance concrete. In the fresh and hardened state, concretes with partial replacements of Portland cement (CPC30R and OPC40C) by pulverized fly ash in combination with the addition of mineral aggregates and chemical admixtures were studied. The physical, mechanical, and durability properties in terms of slump, density, porosity, compressive strength, and permeability to chloride ions were respectively determined. The microstructural analysis was carried out by scanning electronic microscopy. The results highlight the effect of the addition of expanded clay aggregate on the internal curing of the concrete, which allowed developing the maximum compressive strength at 28 days (61 MPa). Meanwhile, the replacement of fine aggregate by 20% of pumice stone allowed developing the maximum compressive strength (52 MPa) in an OPC-based oncrete at 180 days. The effectiveness of internal curing to develop higher strength is attributed to control in the porosity and a high water release at a later age. Finally, the lowest permeability value at 90 days (945 C) was found by the substitutions of fine aggregate by 20% of pumice stone saturated with shrinkage reducing admixture into pores and OPC40C by 15% of pulverized fly ash. It might be due to impeded diffusion of chloride ions into cement paste in the vicinity of pulverized fly ash, where the pozzolanic reaction has occurred. The proposed internal curing technology can be considered a real alternative to achieve the expected performance of a high-performance concrete since a concrete with a compressive strength range from 45 to 67 MPa, density range from 2130 to 2310 kg/m3, and exceptional durability (< 2000 C) was effectively developed

Healthcare workers hospitalized due to COVID-19 have no higher risk of death than general population. Data from the Spanish SEMI-COVID-19 Registry

Aim To determine whether healthcare workers (HCW) hospitalized in Spain due to COVID-19 have a worse prognosis than non-healthcare workers (NHCW). Methods Observational cohort study based on the SEMI-COVID-19 Registry, a nationwide registry that collects sociodemographic, clinical, laboratory, and treatment data on patients hospitalised with COVID-19 in Spain. Patients aged 20-65 years were selected. A multivariate logistic regression model was performed to identify factors associated with mortality. Results As of 22 May 2020, 4393 patients were included, of whom 419 (9.5%) were HCW. Median (interquartile range) age of HCW was 52 (15) years and 62.4% were women. Prevalence of comorbidities and severe radiological findings upon admission were less frequent in HCW. There were no difference in need of respiratory support and admission to intensive care unit, but occurrence of sepsis and in-hospital mortality was lower in HCW (1.7% vs. 3.9%; p = 0.024 and 0.7% vs. 4.8%; p<0.001 respectively). Age, male sex and comorbidity, were independently associated with higher in-hospital mortality and healthcare working with lower mortality (OR 0.211, 95%CI 0.067-0.667, p = 0.008). 30-days survival was higher in HCW (0.968 vs. 0.851 p<0.001). Conclusions Hospitalized COVID-19 HCW had fewer comorbidities and a better prognosis than NHCW. Our results suggest that professional exposure to COVID-19 in HCW does not carry more clinical severity nor mortality