Webbased rapid and contactless management of ambulatory sufferers for SARSCoV2testing

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Intestinal microflora are known to metabolize urea to ammonia and scavenge nitrogen (N) for the synthesis of amino acids. Studies feeding 15N-ammonium chloride or 15N-urea to animals and to humans, demonstrate the appearance of 15N-lysine in gut microbial lysine and in host lysine. However, the amount of 15N-lysine transferred to the host is difficult to assess directly using current methods. It is important to understand the role of the gut microflora in human lysine metabolism, especially in conditions where dietary lysine intake may be limited, but better methods need to be devised.
Despite the widespread use of l-lysine in dietary supplements, the safety information pertinent to excessive l-lysine ingestion is limited and, to the best of our knowledge, there is no published systematic review of safety.
The objective of this study was to assess the clinical safety of l-lysine supplementation of a regular diet.
We searched PubMed, Cochrane Library, Ichushi Web, and EBSCOhost using the relevant keywords, "l-lysine" and "clinical trial." To investigate all adverse events observed during intervention trials, we included all intervention studies with orally ingested l-lysine without restricting background factors, environment, study designs, and sample sizes.
We identified 71 articles, which included 3357 study subjects. The l-lysine doses ranged from 16.8 to 17.5g/d, and the dosing period ranged from 1 to 1095 d. The observed adverse events were mainly subjective gastrointestinal tract symptoms; however, the risk analysis for incidence of gastrointestinal symptoms was not statistically significant (risk ratio of 1.02).
The provisional no-observed-adverse-effect level in healthy human subjects was based on gastrointestinal symptoms and identified at 6.0g/d. The review protocol was registered at umin.ac.jp as UMIN000028914 before the beginning of the study.
The provisional no-observed-adverse-effect level in healthy human subjects was based on gastrointestinal symptoms and identified at 6.0 g/d. The review protocol was registered at umin.ac.jp as UMIN000028914 before the beginning of the study.Atopic dermatitis (AD) is an incurable, inflammatory skin condition that is prevalent (∼20%) in young children. There is an unmet clinical need, particularly in children, for safe interventions that target the etiology of the disease. check details Deficiencies in the skin barrier protein, filaggrin (FLG) have been identified as major predisposing factors in AD. In mammals, l-histidine is rapidly incorporated into epidermal FLG and subsequent FLG proteolysis releases l-histidine as an important natural moisturizing factor (NMF). It has therefore been hypothesized that l-histidine supplementation would be a safe approach to augment both FLG and the NMF, enhance skin barrier function, and reduce AD severity. In a clinical pilot study, adult subjects (n = 24) with AD took either a placebo or 4 g oral l-histidine daily for 8 wk. Unlike the placebo, l-histidine reduced AD (34% reduction in SCORing Atopic Dermatitis scores; P less then 0.003) after 4 wk. Nine and 8 adverse events (AEs), and 1 and 0 severe AEs were recorded in the l-histidine or placebo groups, respectively, with no AE being causally related to l-histidine ingestion. A survey of adults (n = 98) taking 4 g l-histidine daily reiterated a lack of causal AEs and also reported a 33% reduction in topical corticosteroid use. A placebo-controlled, clinical pilot study conducted in young children with AD (n = 49; mean age 3.5 y) taking 0.8 g l-histidine daily, showed that eczema area and severity index scores were reduced by 49% (P less then 0.02) at 12 wk, whereas a placebo had no effect. The children taking l-histidine had 50 minor AEs (compared with 39 on placebo), with 78% considered as "not," 18% "unlikely," and 4% "possibly" related to l-histidine ingestion. These studies indicate that at the levels reported, oral l-histidine supplementation is well tolerated and has potential as a safe intervention for long-term use in the management of AD in all age groups.Methionine is a nutritionally indispensable amino acid, and is unique among indispensable amino acids due to its sulfur atom. Methionine is involved in cysteine synthesis via the transsulfuration pathway, which is rate limiting for the key antioxidant molecule, glutathione. Methionine is also the primary methyl donor in the body through S-adenosylmethionine via the transmethylation pathway, which is involved in the synthesis of several key metabolites including creatine and phosphatidylcholine. Methionine can also be remethylated from homocysteine, in the presence of betaine via choline and/or folate. Thus methionine demands from a dietary perspective are regulated not only by the presence of cysteine in the body, but also by the demands in vivo for the various metabolites formed from it, and also by the presence of these compounds in foods. Indeed, methionine, cysteine, and the various methyl donors/acceptors vary in human foods, and thus regulate methionine availability, especially under conditions of growth and development. Much of our understanding of methionine nutrition and metabolism arises from experiments in animal models. This is because most animal feed formulations are plant-based and plant sources are relatively low in methionine and cysteine amounts. Thus, this brief review will touch on some broad aspects of human methionine nutrition, including requirements in different life stages, disease, and bioavailability, with some examples from the insights/lessons learned from experiments initially conducted in animals.We examined international regulatory developments related to the use of proteinogenic amino acids in human nutrition and concluded that the current risk-assessment practices tend to focus exclusively on setting maximum daily limits. In this brief review we argue that controlling the standards of purity and ingredient quality are the key safety issues that should be considered during risk assessment. Moreover, if maximum intake limits on amino acids are implemented, they should be defined using a well-established rationale for the health risks associated with high intakes. This would avoid setting limits that are so low that they render the dietary supplements ineffective and which, therefore, could mislead the consumer. We further suggest that there should be greater regional concordance in how the use of amino acids as ingredients is regulated and use the capacity of industry to oversee pre-competitive issues, such as standards of purity and scientific research on the safety of generic ingredients. Our arguments are based on clinical safety scientific research and oversights of amino acid purity standards conducted in the last decade by the not-for-profit international association, the International Council on Amino Acid Science.