A new method for chemically altering human urine could be used for producing medical implants and construction materials, scientists claim.
Category: chemistry
Natural compounds and strategies for fighting against drug resistance in cancer: a special focus on phenolic compounds and microRNAs
Bioactive phytochemicals, phenolic compounds, terpenoids, and alkaloids, exert antioxidative, anti-inflammatory, antigenotoxic, and anticancer effects, simultaneously showing minimal or no toxicity on normal, healthy cells. Phytochemicals targeting various signaling pathways and multiple mechanisms underlying intrinsic and acquired multidrug resistance (MDR) in cancer cells make them invaluable tools for the development of novel strategies for fighting against anticancer drug resistance in different types of cancer, which is one of the ultimate goals of modern oncology research. As MDR is described to be a simultaneous development of resistance to multiple drugs with different chemical structures, mechanisms of action, and targets it is not surprising that multiple factors, such as genetic and epigenetic changes, as well as noncoding RNAs, including microRNAs may significantly contribute to the development MDR in cancer cells, and its targeting and modulation of their expression to sensitize cells to treatment. This review implies that some natural compounds, such as curcumin, resveratrol, kaempferol, allicin, and quercetin, have the potential to interact with highly oncogenic and/or proinflammatory miRNAs, such as miR-21/155/663/146a, significantly influencing the response to cancer therapy. This article aims to point out how natural compounds may be used, accompanied by miRNAs mimics or miRNA inhibitors to treat specific types of cancer and its subtypes to overcome multidrug resistance. The main challenge is to determine the proper doses and concentrations of both miRNAs and compounds.
Relationships between electronegativity and genotoxicity
The mean electronegativity of chemicals tested for mutagenicity, genotoxicity, clastogenicity and toxicity was determined. It was found that, as expected, chemicals with ‘structural alerts’ for DNA reactivity, and/or capable of inducing mutations in Salmonella and/or unscheduled DNA synthesis in hepatocytes, as a group, were significantly more electronegative than the molecules lacking these attributes. Molecules capable of inducing somatic mutations and recombinations in Drosophila melanogaster also exhibited this characteristic although it was of borderline statistical significance. Inducers of chromosomal aberrations and sister-chromatid exchanges in cultured CHO cells showed the same trend, however the differences between inducers and non-inducers were not statistically significant. In contrast to the above, inducers of bone marrow micronuclei, as a group, were significantly less electronegative than non-inducers. This is a property they shared with chemicals that exhibited systemic or cellular toxicity or that induced lethality in minnows. These findings suggest that in addition to genotoxicity, cellular and/or systemic toxicity may also contribute to the induction of micronuclei.
Scientists use lightning to make ammonia out of thin air
University of Sydney researchers have harnessed human-made lightning to develop a more efficient method of generating ammonia—one of the world’s most important chemicals. Ammonia is also the main ingredient of fertilizers that account for almost half of all global food production.
The research was published in Angewandte Chemie International edition.
The team have successfully developed a more straightforward method to produce ammonia (NH3) in gas form. Previous efforts by other laboratories produced ammonia in a solution (ammonium, NH4+), which requires more energy and processes to transform it into the final gas product.
Magnetism recharged: A new method for restoring magnetism in thin films
Modern low-power solutions to computer memory rely heavily on the manipulation of the magnetic properties of materials. Understanding the influence of the chemical properties of these materials on their magnetization ability is of key importance in developing the field.
A study published in Applied Physics Letters, led by researchers from SANKEN at The University of Osaka, has revealed a technique for recovering magnetism in a degraded spintronics device. This method can be applied to improve the robustness of next-generation semiconductor memory.
Spintronics exploits the spin (and charge) of electrons to process and store memory, and this is achieved practically by stacking layers of thin material films that behave differently under the influence of a magnetic field.
AI and biophysics unite to forecast high-risk viral variants before outbreaks
When the first reports of a new COVID-19 variant emerge, scientists worldwide scramble to answer a critical question: Will this new strain be more contagious or more severe than its predecessors? By the time answers arrive, it’s frequently too late to inform immediate public policy decisions or adjust vaccine strategies, costing public health officials valuable time, effort, and resources.
In a pair of recent publications in Proceedings of the National Academy of Sciences, a research team in the Department of Chemistry and Chemical Biology combined biophysics with artificial intelligence to identify high-risk viral variants in record time—offering a transformative approach for handling pandemics. Their goal: to get ahead of a virus by forecasting its evolutionary leaps before it threatens public health.
“As a society, we are often very unprepared for the emergence of new viruses and pandemics, so our lab has been working on ways to be more proactive,” said senior author Eugene Shakhnovich, Roy G. Gordon Professor of Chemistry. “We used fundamental principles of physics and chemistry to develop a multiscale model to predict the course of evolution of a particular variant and to predict which variants will become dominant in populations.”
A new quantum dot photoreductant uses 99% less light energy for organic reactions
Chemists at the School of Science of the Hong Kong University of Science and Technology (HKUST) have recently made significant progress in photocatalysis by unveiling a “super” photoreductant, marking a major advancement in organic synthesis.
Quantum dots (QDs) hold great promise as photocatalysts for promoting photoredox chemistry. However, their application in photocatalytic organic transformations has lagged behind that of small molecule photosensitizers due to the limited understanding of their photophysics.
While various studies have explored the generation of hot electrons from QDs as a strategy to enhance photoreduction efficiencies, achieving effective hot-electron generation under mild conditions has posed a significant challenge.
AI helps discover optimal new material for removing radioactive iodine contamination
Managing radioactive waste is one of the core challenges in the use of nuclear energy. In particular, radioactive iodine poses serious environmental and health risks due to its long half-life (15.7 million years in the case of I-129), high mobility, and toxicity to living organisms.
A Korean research team has successfully used artificial intelligence to discover a new material that can remove iodine for nuclear environmental remediation. The team plans to push forward with commercialization through various industry–academia collaborations, from iodine-adsorbing powders to contaminated water treatment filters.
Professor Ho Jin Ryu’s research team from the Department of Nuclear and Quantum Engineering, in collaboration with Dr. Juhwan Noh of the Digital Chemistry Research Center at the Korea Research Institute of Chemical Technology, developed a technique using AI to discover new materials that effectively remove radioactive iodine contaminants. Their research is published in the Journal of Hazardous Materials.
