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Bustamante, M., & Lefranc, G. (2011). Degradation Model Of Breast Imaging By Dispersed Radiation. Proc. Rom. Acad. Ser. A-Math. Phys., 12(4), 347–352.
Abstract: This paper presents a model of interaction of radiation on breast, based on Bosso's filter. This model is used to improve mammographic images for early cancer diagnosis, to be more accurate and to detect cluster of microcalcifications. The model is based on degradation of breast image produced by dispersed radiation using the Bosso's filter, developed earlier.
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Bustamante, M., Rienzo, A., Osorio, R., Lefranc, E., Duarte, M., Herrera, E., et al. (2018). Algorithm for Processing Mammography: Detection of Microcalcifications. IEEE Latin Am. Trans., 16(9), 2460–2466.
Abstract: A new algorithm based in Creme Filter, is proposed for breast cancer detection. The images obtained show micro calcifications with better contrast, allowing a better prognosis. The algorithm has only one parameter free, that permitting to observe texture when parameter is changed.
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Karthikeyan, C., Sisubalan, N., Varaprasad, K., Aepuru, R., Yallapu, M. M., Mangalaraja, R. V., et al. (2022). Hybrid nanoparticles from chitosan and nickel for enhanced biocidal activities. New J. Chem., 46(27), 13240–13248.
Abstract: Chitosan (Cs) is highly useful for its 'tunable' function, hence allowing numerous optimizable applications in various fields, including the pharmaceutical industry. This has piqued the medicinal chemist's interest in developing innovative synthetic methodologies to produce a biologically optimistic pharmacophore. In order to design a highly environment-friendly artificial process for the production of Cs/Ni/NiO, hybrid nanoparticles (HNPs) were prepared by an inexpensive chemical synthesis method. The synthesized HNPs were characterized by XRD, DLS, and ATR-FTIR analyses. The morphology and elemental analyses of Cs/Ni/NiO HNPs were investigated using FESEM, TEM, and EDX procedures. Cs/Ni/NiO HNPs bactericidal activity was significant for inhibiting pathogenic bacterial strains, namely, S. aureus and E. coli. Furthermore, Cs/Ni/NiO HNPs exhibited potent cytotoxicity against MCF-7. The findings of the study on the biocompatibility of Cs/Ni/NiO HNPs on the L929 cell lines showed a non-cytotoxic tendency toward normal cells. As a result, the report demonstrated that the chemically engineered Cs/Ni/NiO HNPs have biological properties that are effective against MDR pathogenic bacteria and carcinoma cells. More research is, however, needed to ascertain whether improving the morphology of these Cs/Ni/NiO HNPs will enhance their antibacterial and anticancer properties.
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Kong, Q. X., Mondschein, S., & Pereira, A. (2018). Effectiveness of breast cancer screening policies in countries with medium-low incidence rates. Rev. Saude Publica, 52, 9 pp.
Abstract: Chile has lower breast cancer incidence rates compared to those in developed countries. Our public health system aims to perform 10 biennial screening mammograms in the age group of 50 to 69 years by 2020. Using a dynamic programming model, we have found the optimal ages to perform 10 screening mammograms that lead to the lowest lifetime death rate and we have evaluated a set of fixed inter-screening interval policies. The optimal ages for the 10 mammograms are 43, 47, 51, 54, 57, 61, 65, 68, 72, and 76 years, and the most effective fixed inter-screening is every four years after the 40 years. Both policies respectively reduce lifetime death rate in 6.4% and 5.7% and the cost of saving one life in 17% and 9.3% compared to the 2020 Chilean policy. Our findings show that two-year inter-screening interval policies are less effective in countries with lower breast cancer incidence; thus we recommend screening policies with a wider age range and larger inter-screening intervals for Chile.
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Valle, H., Palao-Suay, R., Aguilar, M. R., Lerma, T. A., Palencia, M., Mangalaraja, R. V., et al. (2023). Nanocarrier of α-Tocopheryl Succinate Based on a Copolymer Derivative of (4,7-dichloroquinolin-2-yl)methanol and Its Cytotoxicity against a Breast Cancer Cell Line. Polymers, 15(22), 4342.
Abstract: In order to improve the water solubility and, therefore, bioavailability and therapeutic activity of anticancer hydrophobic drug alpha-tocopherol succinate (alpha-TOS), in this work, copolymers were synthesized via free radicals from QMES (1-[4,7-dichloroquinolin-2-ylmethyl]-4-methacryloyloxyethyl succinate) and VP (N-vinyl-2-pirrolidone) using different molar ratios, and were used to nanoencapsulate and deliver alpha-TOS into cancer cells MCF-7. QMES monomer was chosen because the QMES pendant group in the polymer tends to hydrolyze to form free 4,7-dichloro-2-quinolinemethanol (QOH), which also, like alpha-TOS, exhibit anti-proliferative effects on cancerous cells. From the QMES-VP 30:70 (QMES-30) and 40:60 (QMES-40) copolymers obtained, it was possible to prepare aqueous suspensions of empty nanoparticles (NPs) loaded with alpha-TOS by nanoprecipitation. The diameter and encapsulation efficiency (%EE) of the QMES-30 NPs loaded with alpha-TOS were 128.6 nm and 52%; while for the QMES-40 NPs loaded with alpha-TOS, they were 148.8 nm and 65%. The results of the AlamarBlue assay at 72 h of treatment show that empty QMES-30 NPs (without alpha-TOS) produced a marked cytotoxic effect on MCF-7 breast cancer cells, corresponding to an IC50 value of 0.043 mg mL-1, and importantly, they did not exhibit cytotoxicity against healthy HUVEC cells. Furthermore, NP-QMES-40 loaded with alpha-TOS were cytotoxic with an IC50 value of 0.076 mg mL-1, demonstrating a progressive release of alpha-TOS; however, the latter nanoparticles were also cytotoxic to healthy cells in the range of the assayed concentrations. These results contribute to the search for a new polymeric nanocarrier of QOH, alpha-TOS or other hydrophobic drugs for the treatment of cancer or others diseases treatable with these drugs.
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Vicuna, L., Fernandez, M. I., Vial, C., Valdebenito, P., Chaparro, E., Espinoza, K., et al. (2019). Adaptation to Extreme Environments in an Admixed Human Population from the Atacama Desert. Genome Biol. Evol., 11(9), 2468–2479.
Abstract: Inorganic arsenic (As) is a toxic xenobiotic and carcinogen associated with severe health conditions. The urban population from the Atacama Desert in northern Chile was exposed to extremely high As levels (up to 600 μmg/l) in drinking water between 1958 and 1971, leading to increased incidence of urinary bladder cancer (BC), skin cancer, kidney cancer, and coronary thrombosis decades later. Besides, the Andean Native-American ancestors of the Atacama population were previously exposed for millennia to elevated As levels in water (similar to 120 μg/l) for at least 5,000 years, suggesting adaptation to this selective pressure. Here, we performed two genome-wide selection tests-PBSn1 and an ancestry-enrichment test-in an admixed population from Atacama, to identify adaptation signatures to As exposure acquired before and after admixture with Europeans, respectively. The top second variant selected by PBSn1 was associated with LCE4A-C1orf68, a gene that may be involved in the immune barrier of the epithelium during BC. We performed association tests between the top PBSn1 hits and BC occurrence in our population. The strongest association (P = 0.012) was achieved by the LCE4A-C1orf68 variant. The ancestry-enrichment test detected highly significant signals (P = 1.3 x 10(-9)) mapping MAK16, a gene with important roles in ribosome biogenesis during the G1 phase of the cell cycle. Our results contribute to a better understanding of the genetic factors involved in adaptation to the pathophysiological consequences of As exposure.
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