Lead toxicity is a major public health issue in developed and developing countries. Both acute and chronic lead exposure has the potential to cause many deleterious systematic effects including hypertension, frank anemia, cognitive deficits, infertility, immune imbalances, delayed skeletal and deciduous dental development, vitamin D deficiency, and gastrointestinal effects. The underlying mechanisms for all these systemic effects have not been elucidated completely. However, the most plausible cause is free radical damage. In addition to this, lead being a divalent cation can surrogate for calcium at multiple levels affecting various cell signaling pathways. The molecular basis of lead exposure resulting in various systemic effects is being extensively explored. The reports include single nucleotide polymorphisms, epigenetic modifications in susceptible individuals, and the most recent reports also feature regulatory RNA molecules – miRNAs. However, many genetic targets are identified, but their possible mechanisms are still an area to be explored. Additional studies are needed in different population groups to validate the existing findings, as well as to find newer targets that may help in better understanding the molecular mechanisms contributing to lead toxicity. Furthermore, newer strategies for lead risk assessment becomes necessary as the previously recognized “safe” level of lead is also being found to be associated with negative health outcomes.

Sarita Choudhary, M.D., Karli Sreenivasulu, Ph.D., Prasenjit Mitra, M.D., Sanjeev Misra, M.S., M.Ch., and Praveen Sharma, Ph.D.. Ann Lab Med 2021;41:129-38. https://doi.org/10.3343/alm.2021.41.2.129

The novel Coronavirus Disease 2019 (COVID-19), that began in Wuhan Province, China was labelled as an International Public Health Emergency on January 30, 2020 and later was declared a pandemic by the World Health Organisation (WHO) on March 11, 2020. The causative agent, SARS-CoV-2 was the third coronavirus responsible for causing major disease outbreaks in human population after Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) caused by SARS-CoV and MERS-CoV respectively. The patients of COVID-19 present with a clinical feature resembling mild form of viral pneumonia which in certain cases progress to a severe form characterised by adult respiratory distress syndrome (ARDS) and/or multiorgan failure leading to death. The transition from mild to severe form of COVID-19 is affected by a lot of factors like age, co-morbidities etc. In the absence of an absolute cure, it is essential to explore the molecular pathogenesis of the disease to identify people at risk of developing severity so that alternative treatment modalities may be planned. The aim of this review is to provide an update on the general characteristics of SARS-CoV-2 and highlight the inflammatory changes and immune dysregulation that may help in identification of molecular predictors of disease severity.