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Notes on Genetic and Radiation Control of Senescence
Published in Nate F. Cardarelli, The Thymus in Health and Senescence, 2019
Metal interactions with DNA are fairly well known. For instance, DNA will bind magnesium.170–175 The enzymatic incorporation of ribonucleotides into RNA requires the presence of divalent ions, magnesium and manganese being stimulatory at low concentrations and inhibitory at higher ones.173 An enzyme fraction from calf thymus nuclei catalyzed incorporation of deoxyribonucleotides into the terminal regions of DNA.174 This material required the presence of Mg++ for such activity to occur. Mg++ also induces ribosome subunit association, which is critical for mRNA translation.176 Watanabe and Iso noted that magnesium ion induces conformational changes in DNA.177 They also found that histone H1 inhibits Mg++ binding to chromatin.
Mitochondrial Pathologies and Their Neuromuscular Manifestations
Published in Shamim I. Ahmad, Handbook of Mitochondrial Dysfunction, 2019
Carlos Ortez, Andrés Nascimento
TK2 deficiency is a MiDs that may be under diagnosed due to its diverse spectrum of clinical presentations. Recently, molecular bypass treatment with deoxypyrimidine monophosphates has been demonstrated to prolong the life span and to ameliorate clinical, molecular and biochemical defects in the Tk2 H126N knockin mouse model37. The increasing cellular availability of the deficient deoxyribonucleoside triphosphates precursor by direct administration of the deoxyribonucleosides or inhibition of its catabolism is a potential treatment for mtDNA depletion syndrome caused by defects in dNTP metabolism38.
Genetics
Published in Frank J. Dye, Human Life Before Birth, 2019
Our consideration of DNA replication has used a simple example—having to do with scale, among other things. When two deoxyribonucleotides are hydrogen-bonded together in the DNA molecule (e.g., A-T), they are referred to as a base pair. The DNA in the nucleus of a single human cell contains 3 billion base pairs. Indeed, it was the goal of the multibillion-dollar international scientific effort called the Human Genome Project to determine the sequence of all 3 billion base pairs. Why? Because the sequence is information, and one use of information is improved medical care. Note that each diploid (having two sets of chromosomes) human cell has 46 chromosomes, and each chromosome contains a single DNA molecule, and therefore each chromosome has, on average, millions of base pairs (our example of DNA replication above, with 12 base pairs, was obviously a simplification of scale).
Identification and quantification of isoguanosine in humans and mice
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2019
Allan Weimann, George McLeod, Trine Henriksen, Vanja Cejvanovic, Henrik E. Poulsen
To determine whether the 2′-deoxyribonucleoside analogous could be found in DNA, DNA was isolated and hydrolyzed from mouse livers and analyzed for the presence of 2′-deoxy-isoguanosine. Urine was also tested for the presence of 2′-deoxy-isoguanosine. The detection limit for 2′-deoxy-isoguanosine was similar to that of isoguanosine in these experiments (this was judged from that the sensitivities for the two analytes were similar upon tuning and when urine was spiked to 10 nM with 2′-deoxy-isoguanosine a huge signal of same magnitude as a pure 10 nM standard was observed), but a signal for 2′-deoxy-isoguanosine could not be detected. This is consistent with previously reported results for human cells and Escherichia coli [22]; therefore, we consider it to be established that 2′-deoxy-isoguanosine is either not present in mouse liver DNA and urine or is only present in very low and currently undetectable concentrations. The deoxyribonucleoside was also undetectable in CSF.
Transcriptome analysis identifies key regulators and networks in Acute myeloid leukemia
Published in Hematology, 2019
Jiaxin Ye, Daliang Luo, Jianhong Yu, Sibo Zhu
Next, we observed that the target genes of hub miRNAs were related to cell growth, proliferation, death, and survival. Pathway analysis demonstrated that the ATP enzyme was significantly affected by miRNA regulation. The ATP was involved in biosynthesis pathways which were significantly enriched. Salvage Pathways of Pyrimidine Deoxyribonucleotides was a pathway related to the biosynthesis of deoxyribonucleotides. ATP played a very important role in this biological procedure [19–23]. Deoxyribonucleotides were essential to DNA synthesis/repair. The previous study demonstrated that the biosynthesis of deoxyribonucleotides was an important target for anticancer therapy [24,25].
The efficacy and safety of BM-PHA for the correction of nasolabial folds: a multicenter, randomized, double-blind, split-face clinical trial
Published in Journal of Dermatological Treatment, 2021
Seung Hwan Paik, Myoung Eun Choi, Woo Jin Lee, Sung Eun Chang, Mi Woo Lee, Jee Ho Choi, Beom Joon Kim, Chong Hyun Won
Purified PNs derived from the germ cells of salmon and other fish have been used as an innovative material for skin rejuvenation (15,16). Products containing PNs have been used not only to fill soft tissue defects, but also to improve tissue regeneration (16). A randomized, double-blind, matched-pairs, active-controlled clinical trial to compare the efficacy of PN fillers and HA demonstrated that the PN fillers could stimulate fibroblast growth for skin rejuvenation as well as exerting a volumizing effect, making them more suitable for skin regeneration (15). The use of long-chain PNs for skin rejuvenation is primarily based on their wound-healing and antiinflammatory effects (16). It has been proven that PNs promote reparation on ultraviolet B (UBV)-exposed dermal fibroblasts (23). They exert their effects via activation of adenosine A2A receptors that regulate the cytokine network by inhibiting the secretion of inflammatory cytokines (24). It is likely that they are cleaved to provide a source for deoxyribonucleotides and deoxyribonucleosides, which enhances the proliferation and activity of cells of different tissues, making them repair-stimulating agents (7,25). Furthermore, PNs contribute to the regeneration of several key autologous skin components that help to maintain physiological functions, including glycosaminoglycans, proteins, glycoproteins, and fibrils (26). BM-PHA contains PNs with cross-linked HA hydrogel, which should maximize the effects of skin rejuvenation in addition to correcting the nasolabial folds. However, this study focused mainly on BM-PHA’s volumizing effect in the correction of nasolabial folds; further studies are needed to demonstrate the effects of skin rejuvenation when BM-PHA is applied to fine wrinkles.