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Article tries to visualize the potential for carcinogenic trigger in humans with a preference for oxidative synthetic of hair dyeing formulations, especially which belong to the category of permanent colours. According to the International Agency for Cancer, hair dyes for personal use are not strictly classified as carcinogen to humans. However, some controversy exists that requires clarification. Some epidemiological studies support the association between the risk of cancer development and personal use of hair dyes (pooled relative risk RR = 1.50. 95% CI: 1.30-1.98). The world-wide sale of hair dyeing cosmetics have exceeded 15 billion dollars by the year 2012 and has maintained an annual growth rate of 8-10%. This raises concerns and need to be addressed. The review article briefly discusses about the different hair dye components based on their chemical nature, permanence, interaction of dye components with different parts of the hair shaft, action mechanisms, health risk assessment, associated challenges and possible alternatives. There appears variability towards the pathological changes incurred in the human system upon the use of synthetic hair formulations. This probably appears due to the presence of interindividual genetic variation of enzymes handling these xenobiotics. The redox mechanism of major hair dye components appears to be involved in the carcinogenic trigger. Most of the hair dye constituents pose serious health issues. However, we do have few better alternatives to prevent the toxicity associated with hair dye constituents without compromising the need of today's fashion statement and expectations of the youth.
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Introduction: Many new variants of the coronavirus are infecting the already vaccinated people. There have been reports of deaths also among the already vaccinated subjects. Hence, we conducted a systematic review and meta-analysis of the infection breakthrough after COVID vaccination. Materials and Methods: We piloted a review of the healthcare workers who completed the vaccination for COVID. The data were collected from the online resources for the breakthrough infections after vaccination. We then enumerated those subjects who had a breakthrough infection post-vaccination. The data collected were meta-analyzed for the incidence of the infection among the vaccinated individuals. Results: We observed that among nearly 2.3 lakh subjects, less than 3% were infected with the various new strains of the virus. The ratio of the breakthrough infection was different for the vaccinated (1.2%) and the partially vaccinated (3.2%) individuals with greater infection among the partially infected individuals. Discussion: The breakthrough infections are very low among vaccinated individuals and even lower among fully vaccinated individuals. Hence, vaccination is highly recommended to prevent the loss of life.
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Peroxynitrite is a powerful oxidant, formed from the reaction of nitric oxide and superoxide. It is known to interact and modify different biological molecules such as DNA, lipids and proteins leading to alterations in their structure and functions. These events elicit various cellular responses, including cell signaling, causing oxidative damage and committing cells to apoptosis or necrosis. This review discusses nitrosative stress-induced modification in the DNA molecule that results in the formation of 8-nitroguanine and 8-oxoguanine, and its role in disease conditions. Different approaches of cell death, such as necrosis and apoptosis, are modulated by cellular high-energy species, such as ATP and NAD+. High concentrations of peroxynitrite are known to cause necrosis, whereas low concentrations lead to apoptosis. Any damage to DNA activates cellular DNA repair machinery, like poly(ADP-ribose) polymerase (PARP). PARP-1, an isoform of PARP, is a DNA nick-sensing enzyme that becomes activated upon sensing DNA breakage and triggers the cleavage of NAD+ into nicotinamide and ADP-ribose and polymerizes the latter on nuclear acceptor proteins. Peroxynitrite-induced hyperactivation of PARP causes depletion of NAD+ and ATP culminating cell dysfunction, necrosis or apoptosis. This mechanistic pathway is implicated in the pathogenesis of a variety of diseases, including circulatory shock (which is characterized by cellular hypoxia triggered by systemic altered perfusion and tissue oxygen utilization leading end-organ dysfunction), sepsis and inflammation, injuries of the lung and the intestine. The cytotoxic effects of peroxynitrite centering on the participation of PARP-1 and ADP-ribose in previously stated diseases have also been discussed in this review.
