Vitamin A Deficiency, COVID-19, and Rhino-Orbital Mucormycosis (Black Fungus): An Analytical Perspective.

Mucormycosis is a rare but serious opportunistic fungal disease characterized by rhino-orbito-cerebral and pulmonary involvement. It is mainly seen in people with secondary immunosuppression, isolated vitamin A deficiency, measles, and AIDS patients. It showed a rise during the second wave of the COVID-19 epidemic in the spring of 2021 in India, especially in diabetic COVID-19 patients. Vitamin A deficiency is known to cause nutritional immunodeficiency and hence leading the way to increased opportunistic fungal, bacterial, and viral infections. In the eye, it causes keratitis, night blindness, xerophthalmia, conjunctivitis, Bitot spots, keratomalacia, and retinopathy. It also causes decreased tear secretion and deterioration of the anatomical/physiological defense barrier of the eye. The negative impact of vitamin A deficiency has been previously demonstrated in measles, AIDS, and COVID-19. We think that mucormycosis in COVID-19 might be rendered by vitamin A deficiency and that vitamin A supplementation may have preventive and therapeutic values against mucormycosis and other ocular symptoms associated with COVID-19. However, any vitamin A treatment regimen needs to be based on laboratory and clinical data and supervised by medical professionals.

CRISPR-Cas13 System as a Promising and Versatile Tool for Cancer Diagnosis, Therapy, and Research.

Over the past decades, significant progress has been made in targeted cancer therapy. In precision oncology, molecular profiling of cancer patients enables the use of targeted cancer therapeutics. However, current diagnostic methods for molecular analysis of cancer are costly and require sophisticated equipment. Moreover, targeted cancer therapeutics such as monoclonal antibodies and small-molecule drugs may cause off-target effects and they are available for only a minority of cancer driver proteins. Therefore, there is still a need for versatile, efficient, and precise tools for cancer diagnostics and targeted cancer treatment. In recent years, the CRISPR-based genome and transcriptome engineering toolbox has expanded rapidly. Particularly, the RNA-targeting CRISPR-Cas13 system has unique biochemical properties, making Cas13 a promising tool for cancer diagnosis, therapy, and research. Cas13-based diagnostic methods allow early detection and monitoring of cancer markers from liquid biopsy samples without the need for complex instrumentation. In addition, Cas13 can be used for targeted cancer therapy through degrading and manipulating cancer-associated transcripts with high efficiency and specificity. Moreover, Cas13-mediated programmable RNA manipulation tools offer invaluable opportunities for cancer research, identification of drug-resistance mechanisms, and discovery of novel therapeutic targets. Here, we review and discuss the current use and potential applications of the CRISPR-Cas13 system in cancer diagnosis, therapy, and research. Thus, researchers will gain a deep understanding of CRISPR-Cas13 technologies, which have the potential to be used as next-generation cancer diagnostics and therapeutics.