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Food Interactions, Sirtuins, Genes, Homeostasis, and General Discussion
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
The key difference between RNA and DNA structures is that the ribose sugar in RNA has a hydroxyl (-OH) group which is absent in DNA, and the thymine base of DNA is replaced by the uracil base in RNA (107, 111–113). The nucleotides that comprise DNA include adenine (A), guanine (G), cytosine (C), and thymine (T); whereas RNA nucleotides include A, G, C, and uracil (U). Moreover, RNA has only one long strand or chain in almost species, except in some viruses, while DNA has a double strand and looks like a twisted ladder in all species from bacteria and plants to invertebrates and humans (107, 111–113). DNA is defined as a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms. The main role of RNA is to transfer the genetic code needed for the creation of proteins from the nucleus to the ribosome (111). This process prevents the DNA from having to leave the nucleus. This keeps the DNA and genetic code protected from damage. Without RNA, proteins could never be made. RNA molecules are not only involved in protein synthesis, but also sometimes in the transmission of genetic information (111).
An Overview of Molecular Nutrition
Published in Nicole M. Farmer, Andres Victor Ardisson Korat, Cooking for Health and Disease Prevention, 2022
Vincent W. Li, Catherine Ward, Delaney K. Schurr
DNA is the genetic material that determines every aspect of the body. Each strand of DNA is made of nucleotides linked together. The nucleotides are then translated into proteins needed for the body’s structure and function. While DNA itself cannot be changed – i.e., the same DNA at birth is kept throughout the entire lifespan – but how DNA is used, or expressed, can be changed. Lifestyle factors like diet, exercise, sleep, and stress can all affect how DNA is used and translated into the proteins it codes. In general, healthy behaviors equate to a greater number of healthy proteins created and the suppression of unhealthy proteins.
Modifications of Cellular Radiation Damage
Published in Kedar N. Prasad, Handbook of RADIOBIOLOGY, 2020
Cyclic nucleotides, adenosine 3′,5′-cyclic-monophosphate (cAMP), and guanosine 3′,5′-cyclic-monophosphate (cGMP) occur in all mammalian cells, and they are formed by catalyzing adenosine triphosphate (ATP) and guanosine triphosphate (GTP) by adenylate cyclase and guanylate cyclase, respectively. cAMP and cGMP are degraded by cAMP phosphodiesterase and cGMP phosphodiesterase, respectively. Numerous studies have shown9–11 that cyclic nucleotides are involved in the regulation of growth, differentiation, and malignancy of certain cell types. Since the rate of proliferation and the degree of differentiation are important factors in determining the radiosensitivity of mammalian cells, the obvious question was whether cyclic nucleotides would modify the radiation response of normal cells or tumor cells.
Clinical pharmacology of siRNA therapeutics: current status and future prospects
Published in Expert Review of Clinical Pharmacology, 2022
Ahmed Khaled Abosalha, Jacqueline Boyajian, Waqar Ahmad, Paromita Islam, Merry Ghebretatios, Sabrina Schaly, Rahul Thareja, Karan Arora, Satya Prakash
Chemical modification acts as a significant strategy to optimize the delivery of naked siRNAs to overcome some delivery obstacles. The negatively charged phosphodiester skeleton of siRNA represents a powerful barrier to its cellular uptake through the anionic lipid bilayers of the cell membrane. Furthermore, the original structure of siRNA candidates makes them highly susceptible to degradation by endonucleases with a poor pharmacokinetic profile. Also, hazardous off-target side effects such as the unintended block of expression of other genes have been reported besides triggering the host immune response [48]. Consequently, chemically modified siRNA therapeutics can offer a high degree of cellular uptake and resistance against endonucleases in addition to minimizing the harmful off-target effects and antigenicity. Generally, both DNA and RNA are composed of nucleotides as building blocks. Nucleotides compromise a ribose or 2′-deoxyribose sugar moiety with 1′-nucleobase and 3′-phosphate groups. Four sites of chemical modifications to siRNA molecules were previously proposed, including the ribose sugar, nucleobase, phosphate link, and strand terminus [17].
An overview of the preclinical discovery and development of remdesivir for the treatment of coronavirus disease 2019 (COVID-19)
Published in Expert Opinion on Drug Discovery, 2022
Pasquale Pagliano, Carmine Sellitto, Giuliana Scarpati, Tiziana Ascione, Valeria Conti, Gianluigi Franci, Ornella Piazza, Amelia Filippelli
Research on these new antiviral agents that led to the discovery of RDV started with the screening of approximately 1000 small molecules with some activity on RNA viruses through the RdRp. All the molecules were nucleotide analogs; among them, a 1-cyano-substituted adenine C-nucleoside ribose analog (NUC) was found to have potential antiviral activity by inhibiting viral RdRp [31]. NUC analogs acting against RNA viruses need to be converted into an active triphosphate form into the infected cells to interact with the RdRp and consequently inhibit viral RNA synthesis. RDV demonstrated its activity against a broad range of non-segmented negative-sense RNA virus members of families such as Filoviridae, Paramyxoviridae, Pneumoviridae, and Corononaviridae. On the other hand, no in vitro activity of RDV has been reported against other non-segmented negative-sense RNA viruses such as the Lassa virus (Arenaviridae) and the Crimean Congo hemorrhagic fever virus (Bunyaviridae). It is well reported that RDV is active against the Marburg virus and several variants of the EBOV, Nipah virus, and respiratory syncytial virus, as assessed by investigations in primary human macrophages and endothelial cells [32,33]. (Table 2).
Oxysterol concentrations are associated with cholesterol concentrations and anemia in pediatric patients with sickle cell disease
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2019
Ahmet Yalcinkaya, Afshin Samadi, Incilay Lay, Selma Unal, Suna Sabuncuoglu, Yesim Oztas
Sickle cell disease (SCD) identifies a group of hemoglobinopathies in which a single nucleotide mutation in the beta globin gene results in the production of hemoglobin S, a type of hemoglobin that forms polymers in hypoxic conditions which distort the characteristic shape of the erythrocyte [1]. These sickle-shaped erythrocytes are prone to hemolysis which manifests as severe anemia, especially in patients who have inherited two defective beta-globin genes from their parents – a homozygote condition (HbSS) conveniently named as sickle cell anemia (SCA) [2]. Patients who have inherited one copy of the defective gene may also have other beta-globin variants which cause compound hemoglobinopathies such as ß-thalassemia (HbSß), hemoglobin C (HbSC), hemoglobin D disease (HbSD), among others [3]. The most common types of SCD in Turkey are the HbSS and HbSß+ genotypes.