Melatonin (5-methoxy N-acetyltryptamine) is a hormone synthesized and released from the pineal gland at night, which acts on specific high affinity G-protein coupled receptors to regulate various aspects of physiology and behaviour, including circadian and seasonal responses, and some retinal, cardiovascular and immunological functions. Melatonin is also made synthetically and available without a prescription as an over-the-counter (OTC) dietary supplement in the U.S. Melatonin supplementation has many uses, however, it has been widely studied for treatment of jet lag and sleep disorders. Parents may consider using melatonin to help their child who has a trouble falling asleep. A medical professional should always evaluate insomnia or other sleeping disorders in children. Additionally, melatonin has been shown to protect against oxidative stress in various, highly divergent experimental systems. There are many reasons for its remarkable protective potential. In mammals, melatonin binds to a number of receptor subtypes including high-affinity (MT1 and MT2) and low-affinity (MT3, nuclear orphan receptors) binding sites, which are distributed throughout the central nervous system and periphery.

Zirconium is a hard, silvery metal that is very resistant to corrosion. Zirconium orthopedic hip replacements have shown superior wear-resistance over other systems; however, risk of catastrophic fracture remains a concern. In dentistry, zirconium has been widely adopted for endosseous implants, implant abutments, and all-ceramic crowns. Because of an increasing demand for esthetically pleasing dental restorations, zirconia-based ceramic restorations have become one of the dominant restorative choices.

Deoxyguanosine is a nucleoside consisting of the base guanine and the sugar deoxyribose. It is like guanosine, but with one oxygen atom removed. It is a nucleoside component of DNA. Deoxyguanosine can be converted to 8-hydroxy-deoxyguanosine (8-OHdG) due to hydroxyl radical attack at the C8 of guanine. 8-OHdG is a sensitive marker of the DNA damage This damage, if left unrepaired, has been proposed to contribute to mutagenicity and cancer promotion. Deoxyguanosine has long been recognized as a potent cytotoxic agent to cultured mammalian cells. This toxicity or inhibition of DNA synthesis by deoxyguanosine appears to be mediated by deoxyguanosine triphosphate-mediated inhibition of the enzyme ribonucleotide reductase. Purine nucleoside phosphorylase deficiency is thought to cause T-lymphocyte depletion by accumulation of deoxyguanosine and deoxyguanosine triphosphate, resulting in feedback inhibition of ribonucleotide reductase and hence DNA synthesis. Deoxyguanosine nucleoside analogs are potent antiviral agents.

2′-Deoxyadenosine, a pair of deoxythymidine (T) in double-stranded DNA, is a substrate of adenosine deaminase. In case of absence of this enzyme, 2′-deoxyadenosine accumulates in T lymphocytes and kills these cells resulting in a genetic disorder known as adenosine deaminase severe combined immunodeficiency disease (ADA-SCID).

Tocotrienols are a group of chemicals that are part of the vitamin E family. Tocotrienol is any of the four forms, alpha, beta, gamma and delta, of a member of the vitamin E family. It has potential hypocholesterolemic, antithrombotic, antioxidant, immunomodulating and antineoplastic activities. Tocotrienol inhibits the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, thereby lowering cholesterol levels. In addition, tocotrienol acts through multiple signal transduction pathways to induce cell cycle arrest and caspase-mediated apoptosis, and to decrease tumor cell proliferation. In addition, this agent may inhibit angiogenesis through the blockage of vascular endothelial growth factor receptor (VEGFR) and the subsequent inhibition of tumor cell-induced vessel formation. Also, this agent prevents free radical formation and inhibits lipid peroxidation, thereby preventing DNA cell damage. Tocotrienols are scare in nature. They are found most abundantly in crude palm oil extracted from palm fruits. Other sources are rice bran, wheat germ, oat and barley. These substances are available in supplement form as capsules or pills.

Thymidine is a water-soluble pyrimidine deoxynucleoside and potent thymidine kinase substrate. Thymidine is known to be converted to dTTP and utilized for DNA synthesis. It is also known that thymidine is converted by catabolic enzymes to several end products. Excess thymidine results in high levels of dTTP, which exerts a regulatory feedback inhibition in the nucleotide biosynthesis pathways leading to DNA synthesis. This property of thymidine is used when it is given in high doses to patients with solid tumors. Thymidine is being tested in Phase II of clinical trials for the treatment of cancer and 5'-Nucleotidase Syndrome.

Butyric acid (butanoic acid) belongs to a group of short-chain fatty acids and is thought to play several beneficial roles in the gastrointestinal tract. The butyric anion is easily absorbed by enteric cells and used as a main source of energy. Moreover, butyric acid is an important regulator of colonocyte proliferation and apoptosis, gastrointestinal tract motility and bacterial microflora composition in addition to its involvement in many other processes including immunoregulation and anti-inflammatory activity. Butyric acid shows a protective effect in inflammatory response secondary to inflammatory bowel diseases. A beneficial effect of butyric acid as one constituent of a multifaceted mechanism modulating gastrointestinal function has also been stressed in patients with the stoma and coexisting constipation. Butyric acid supplementation combined with the use of probiotics should be adopted as one of the basic therapeutic strategies in this patient group, preceding treatment with laxatives. Sodium butyrate in the form of enemas (combined in a mixture with A-300 silicon dioxide) may be a successful method of therapeutic management in patients with radiation proctitis. Sodium butyrate may also prevent diarrhea through an increased passive absorption of water in the colon and its effects on the gut microflora.

Pyridoxal is a pyridinecarbaldehyde and a form of vitamin B 6 which is converted to pyridoxal phosphate. Pyridoxal 5'-phosphate is involved in a wide range of biochemical reactions, including the metabolism of amino acids and glycogen, the synthesis of nucleic acids, hemoglobin, sphingomyelin, and other sphingolipids, and the synthesis of the neurotransmitters serotonin, dopamine, norepinephrine and gamma-aminobutyric acid (GABA). Pyridoxal is one of the natural forms available of vitamin B6, therefore, it is used for nutritional supplementation and for treating dietary shortage or imbalances. Some medically relevant bacteria, such as those in the genera Granulicatella and Abiotrophia, require pyridoxal for growth. This nutritional requirement can lead to the culture phenomenon of satellite growth. In in vitro culture, these pyridoxal-dependent bacteria may only grow in areas surrounding colonies of bacteria from other genera ("satellitism") that are capable of producing pyridoxal.

Beta-alanine is an endogenous agonist of glycine receptor, which is used a supplementation among competitive athletes participating in a range of different sports. Beta-alanine has been shown to enhance muscular endurance and its supplementation appears to be most effective for exercise tasks that rely heavily on ATP synthesis from anaerobic glycolysis.