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Blood Transfusion
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
Normally, 400–480 mL blood is taken with 63 mL anticoagulant, which is either citrate–phosphate–dextrose (CPD; sodium citrate 1.66 g, anhydrous dextrose 1.46 g, citric acid monohydrate 206 mg, sodium acid phosphate 158 g and water to 63 mL), CPD–adenine (sodium citrate 1.66 g, anhydrous dextrose 1.82 g, citric acid monohydrate 206 g, sodium acid phosphate 158 mg, adenine 17.3 mg and water to 63 mL) or SAGM (saline, adenine, glucose and mannitol). The addition of adenine prolongs the shelf life to 35 days. The citrate combines with calcium and anticoagulates the blood. The function of mannitol in SAGM is to protect the red cell membrane and reduce haemolysis and enables the refrigerated storage of red blood cells to be extended up to 6 weeks. The acidic additive solutions (pH = 5.6–5.8) are used simply because it is easier to heat sterilize the glucose-containing solutions at an acidic pH. This is because glucose caramelizes at physiological and alkaline pH during heat sterilization.
Micronutrient Supplementation and Ergogenesis — Metabolic Intermediates
Published in Luke Bucci, Nutrients as Ergogenic Aids for Sports and Exercise, 2020
Adenine, however, is well absorbed from the diet and incorporated into nucleotides in vivo.589 Adenine is also commonly used to preserve stored erythrocytes,590 and was named vitamin B4 until its nonessentiality was proven.553 Sublingual and parenteral administration of adenosine and adenosine phosphates by German clinicians have been reported to lower serum cholesterol,591 improve angina and atherosclerotic senility,591 and prevent recurrence of secondary myocardial infarcts.592 However, no reports of oral adenine or adenosine supplementation on athletic performance have been found. In addition, adenine supplementation may lead to renal tubular damage caused by formation of the insoluble metabolite 2,8-dihydroxyadenine, as has been seen in dogs.593 In conclusion, the mechanism of action of purine supplements as ergogenic aids may deserve further study in animals, but potential toxicities may render human testing and use hazardous. At this time, no guidelines for use of inosine or other nucleotides as ergogenic aids are apparent.
Adenine phosphoribosyltransferase (APRT) deficiency
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop
Therapy is aimed at reducing the formation of 2,8-dihydroxyadenine by the use of a low purine diet and allopurinol [3, 15, 50, 53]. A dose of allopurinol of 5–10 mg/kg per day up to 200–300 mg per day in an adult has been reported to eliminate 2, 8-dihydroxyadenine from the urine [15]. Adenine still accumulates. Dosage of 300 mg twice daily has more recently been recommended [44]. In a patient allergic to allopurinol, Febuxostat in a dose of 80 mg daily led to significant reduction of crystalluria [54].
Panax notoginseng saponins alleviate damage to the intestinal barrier and regulate levels of intestinal microbes in a rat model of chronic kidney disease
Published in Renal Failure, 2022
Jing Xie, Xin Ma, Yixuan Zheng, Nan Mao, Sichong Ren, Junming Fan
CKD is caused by the end-stage development of many kidney diseases when the kidneys lose their basic functions, manifested by systemic metabolic dysfunction, abnormal urine and blood indicators, and a poor prognosis [1,23]. Therefore, replication of stable animal models of CKD and selection of positive drugs were key aspects of the search for drugs to combat CKD. Adenine-induced nephropathy is an established model of CKD in rodents. Upon Adenine ingestion, pathological changes are observed in kidney tissues, and renal function is reduced, as indicated by UREA and CREA. These changes are close to the clinical signs of patients with CKD [22,24]. Valsartan was the most commonly applied drug in the treatment of CKD with reduction of urinary protein [25]. In this study, we successfully modeled CKD rats, as evidenced by an increase in 24 h urine volume, a decrease in GFR, and an increase in urinary protein elimination rate. The adenine-induced CKD rat model has been extensively studied in rat models, and the metabolic abnormalities caused by long-term administration of adenine are similar to the clinical and pathological changes in human chronic renal failure [26,27]. We observed that PNS improved renal function and renal histopathological damage in CKD rats in a dose-dependent manner, and at high doses had similar effects to the positive drug valsartan.
Recent developments of RNA-based vaccines in cancer immunotherapy
Published in Expert Opinion on Biological Therapy, 2021
Elnaz Faghfuri, Farhad Pourfarzi, Amir Hossein Faghfouri, Mahdi Abdoli Shadbad, Khalil Hajiasgharzadeh, Behzad Baradaran
Sequence engineering of the ORF and UTRs regions can significantly enhance the mRNA’s expression. For instance, enriching the guanine/cytosine (GC content), or selecting the UTRs of natural enduring mRNAs can manipulate the mRNA’s expression [19]. Moreover, more appealing strategies have been proposed, e.g., the construction of circular-engineered RNAs that are resistant to exonucleases [20]. The co-assembly of mRNA and eIF4E proteins with synthetic polyamines substantially up-regulates the translation efficiency compared to mRNA alone. The underlying reason could be associated with the longer durability and attachment of these complexes to the ribosomes [21]. WO 02/098443 (CureVac GmbH) project has suggested a strategy to optimize mRNAs’ coding sequence. It describes options for substituting adenine and uracil nucleotides in the mRNA structure to enrich its G/C content. This technique can be applied to cancer therapy. In line with it, WO 2007/035355 project has proposed another strategy to increase mRNA translation. It explains how long poly(A) sequences (especially longer than 120 bp) and the combination of at least two 3′ UTRs of the beta-globin gene can increase the mRNA stability and translation capacity [22].
Chromosome aberration in typical biological systems under exposure to low- and high-intensity magnetic fields
Published in Electromagnetic Biology and Medicine, 2020
Emanuele Calabrò, Hit Kishore Goswami, Salvatore Magazù
Chromosomes are molecules composed of the deoxyribonucleic acid (DNA) that represents the genetic material of a living being. In human beings, there are 22 pairs of chromosomes and 2 sex chromosomes for a total of 46. DNA is an organic polymer composed of monomers that are called nucleotides. They consist of a phosphate group and a nitrogenous base linked to deoxyribose by the so-called N-glycoside bond. The nitrogenous bases that can be used in nucleotide formation are adenine, cytosine, guanine and thymine disposed in base pairs of adenine-thymine (A-T) and guanine-cytosine (G-C) that in aqueous solutions are linked one each other by hydrogen bonds forming a double helix structure because of the repulsions between the negative charge of phosphate groups. This double helix structure is bound to proteins (the histones) that have positively charged amino acids in order to bind the DNA which is negatively charged and is wrapped around the core of histone of eight protein subunits forming the nucleosome. About 200 base pairs of DNA are coiled around each histone. This coil is untwisted generating a negative superturn per nucleosome that is the active chromatin.