Simultaneous detection and differentiation between Mycobacterium leprae and Mycobacterium lepromatosis using novel polymerase chain reaction primers

A fluorescent platform integrated with a "one-pot" nicking endonuclease signal amplification and magnetic separation for simultaneous detection of tumor markers

Although Enzyme-linked immunosorbent assay (ELISA) has been widely used for biomedical research, simultaneous sensitive and cost-effective detection of multiple biomarkers is challenging. Herein, we proposed a "one-pot" nicking endonuclease signal amplification (NESA)-based fluorescent aptasensor for simultaneous detection of carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP). Firstly, two aptamers were synchronously immobilized on the surface of magnetic nanoparticles (MNPs) by coupling with two complementary DNA (cDNA). CEA and AFP specifically recognized the aptamers and then the released cDNA (ssDNA) from the double-strands (dsDNA) triggers NESA, further breaking two detection probes which were labeled with the fluorescent dye (FAM and ROX) and its quencher (BHQ1 and BHQ2) at the same time. Then, the fluorescence signal of FAM and ROX were restored separately. The results indicated that the fluorescence intensity at the emission wavelength of 518 nm and 610 nm had a positive correlation with CEA and AFP concentrations, respectively. Under the optimum conditions, wider liner range of 1-500 ng mL-1 to CEA and 5-800 ng mL-1 to AFP of this fluorescent aptasensor were successfully obtained, achieving a detection limit of CEA and AFP were 0.7 ng mL-1 and 2 ng mL-1, respectively. Hence, it turned out that the aptasensor strategy can be a promising candidate for developing a newly fluorescence assay for the simultaneous quantitative detection of multiple tumor markers in matrix samples by changing the corresponding sequences of aptamer and fluorescent signal probe, which has great potential for the screening of early cancer.

Advances in the Diagnosis of Leprosy

Leprosy is a public health issue, and early detection is critical to avert disability. Despite the global attempt to eradicate this disease as a public health problem, it remains an important cause of global neurological disability. India, Brazil and Indonesia share more than 70% of the cases. The reduction of new cases is a priority in the WHO global strategy 2021-2030 which aims to reduce disease transmission in the community by diagnosing cases and identifying subclinical infection. The clinical manifestations of leprosy range from a few to several lesions. The identification remains difficult due to the limited sensitivity of traditional approaches based on bacillary counts of skin smears and histology. To aid in the diagnosis of this disease, molecular biology, and biotechnological technologies have been applied, each with its own set of benefits and downsides despite providing an essential tool to validate the clinical diagnosis of leprosy. Because of this, it is strongly recognized that specific, inexpensive point of care technologies should be developed, particularly to identify asymptomatic M. leprae infections or leprosy nearer to the suspected cases seeking medical attention. Thus, this review will provide an overview of the advancements in leprosy diagnosis over the world. The purpose of this review is to improve our understanding of the outcomes of current tests and technologies used in leprosy diagnosis and to emphasize critical aspects concerning the detection of leprosy bacilli.