Camptothecin (CPT) is a natural alkaloid with potent antiproliferative activity, mediated by the inhibition of Topoisomerase I (Topo I), an essential enzyme for deoxyribonucleic acid (DNA) replication. However, its clinical application has been limited by low solubility and the instability of the lactone ring under physiological conditions, both of which decrease its efficacy. Semi-synthetic analogs such as irinotecan (CPT-11) and topotecan (TPT) have been developed and approved for the treatment of various types of cancer; however, challenges related to drug resistance and side effects continue to arise. Therefore, nanomedicine and nanoparticle-based delivery systems, including nanoemulsions, liposomes, and antibody–drug conjugates (ADCs), emerge as promising strategies to improve the stability, bioavailability, and effectiveness of CPT, despite significant challenges such as scalability, pharmacokinetic variability, and regulatory requirements. This review discusses recent advances in CPT, its analogs, and these delivery platforms, highlighting its potential to optimize cancer therapy and reduce toxicity while outlining translational challenges such as scalability, pharmacokinetic variability, and regulatory requirements.
1 January 2008 in Journal of Biomaterials Science, Polymer Edition
Poly(methyl methacrylate) (PMMA) is one of the most commonly plastics used as dental-base material, due to its good biological compatibility and mechanical properties. Chitosan has wide application in chemical, biochemical and biomedical fields of research. In this work, chitosan (CTS) was functionalized with glycidyl methacrylate (GMA), to ease a further reaction with MMA. The resulting co-polymer was finally blended with PMMA and poly(butyl acrylate) PBA which works as a damper, the polymers were cured by UV to obtain the final resin. Characterization of UV-cured resins was carried out by thermal measurements, X-ray diffraction, atomic force microscopy (AFM), micro and nanoindentation, water absorption and elution in water. As a result a higher thermal stability of the final resin compared with the precursor co-polymer ((CTS-GMA)-g-PMMA) was obtained. The resin presented roughness in the nanometer scale and nanoparticles embedded in the acrylic matrix producing a tough material. However, XRD measurements show that all materials are in an amorphous state. Values of hardness and elastic modulus results were very near to those of the dentine. The results of elution in water of the tested resin samples show them as clinically acceptable as a dental base material.
Porcine epidemic diarrhea (PED) is an intestinal disease caused by the porcine epidemic diarrhea virus (PEDV) and affects Mexico’s swine industry. Despite the disease initially being described in Mexico in 2013, there has been no research into the virus’s seroepidemiology carried out in Mexico. Thus, the goal of this study was to develop an indirect ELISA (iELISA) based on a recombinant N-terminal domain truncated spike (S) protein (rNTD-S) of PEDV to evaluate serum obtained from different pig-producing states in Mexico. A total of 1054 sera were collected from pig farms, slaughterhouses, and backyard production in the states of Aguascalientes, Guanajuato, Hidalgo, Jalisco, Morelos, Queretaro, Sinaloa, and Veracruz between 2019 and 2021. The rNTD-S protein was expressed in E. coli BL21 (DE3) cells. Negative and positive serum samples used in the iELISA were previously tested by Western blot. According to our findings, 61.66% of the serum samples (650/1054) were positive, with Jalisco having the highest percentage of positive samples, at a rate of 21.44% (226/1054). This is the first seroepidemiology study of PEDV carried out in Mexico, revealing that the virus is still circulating since the initial outbreak; furthermore, it provides an overview of PEDV’s spread and high level of persistence across the country’s key swine-producing states.
7 April 2020 in IEEE Transactions on Instrumentation and Measurement
Herein we describe a method to measure turbidity in liquids by probing a graphic pattern by optical transmission. Data are collected by a video camera and a mathematical algorithm is used to correlate image loss with turbidity. We report high-resolution turbidity measurements of nanoparticle colloids to assess the proposed methodology. Measurements are differentially performed which helps reduce noise from external sources. Using Nephelometric Turbidity Units (NTU) standards we obtain detectable measurements in a broad range of NTU from 1.95 to 1000. By implementing the proposed methodology, we proposed a video-based inexpensive yet reliable turbidimetry instrument.
30 September 2019 in European Journal of Lipid Science and Technology
The growing demand for innovative solutions to accurately measure variables in dewatering processes has driven the development of advanced technologies. This study focuses on the evaluation of a measurement system in a rotary dryer used to dehydrate carrots at an operating temperature of 70 °C. The system uses the Arduino platform, strain gauges, and LM35 temperature sensors. Experimental tests were designed to evaluate the performance of the dryer, using initial quantities of carrots of 1.5 kg, 1.0 kg, and 0.5 kg. The novelty of this study lies in the application of fuzzy logic for signal conditioning in real time, in order to improve the precision of measurements, designed in MATLAB (version 9.5) and programmed in Arduino. The dryer reduces the water content of the product to a final average of 10%. The research offers a novel solution for the integration of an intelligent measurement system that optimizes dewatering efficiency. The manuscript is organized as follows: in the methodology section, the design of the measurement system is described; subsequently, the experimental results and the analysis of the dryer efficiency are presented, and finally, in the conclusions, the implications of the system and its possible applications in other processes are discussed.