Immunology and controlling of coronaviruses; the current enemy for humanity: A review.

The Severe Acute Respiratory Syndrome-related Coronavirus 2 (COVID-19 or SARS-CoV-2) epidemic is professed as world disaster producing a worrying increasing mortality, particularly amongst vulnerable humans worldwide. Whether COVID-19 has a strong ability for acceptable genetic flexibility that amended for breaking immune responses quickly, it is critical to understand the adaptation mechanism between viruses and hosts that allows individuals to follow viral development. This can contribute to finding the appropriate treatment to combat the epidemic. However, the present information about viral adaptation mechanisms in hosts is still insufficient, and future investigations may reveal the unknown. Mutations and genetic variations are naturally occurring; however, the current knowledge about their mechanism and pathways still has many secrets. The present review also provides insights into the immune system, immunological memory, and the development of the COVID-19 vaccine. Other fighting methods against COVID-19 are also highlighted. The potential of antibodies, natural metabolites, and current suggest vaccines were applied to the face of this new threat.

Chitosan for biomedical applications, promising antidiabetic drug delivery system, and new diabetes mellitus treatment based on stem cell.

Since chitosan's excellent pharmacokinetic and chemical properties, it is an attractive and promising carbohydrate biopolymer in biomedical applications. Chitosan's beneficial function in the defense and propagation of pancreatic ß cells, reducing hyperglycemia, and avoiding diabetes mellitus associated with impaired lipid metabolism has been demonstrated in several studies. Additionally, chitosan has also been used in various nanocarriers to deliver various antidiabetic drugs to reduce glucose levels. Herein, the first to provide the currently available potential benefits of chitosan in diabetes mellitus treatment focuses on chitosan-based nanocarriers for oral administration of various antidiabetic drugs nasal and subcutaneous passages. Moreover, chitosan is used to activate and deliver stem cells and differentiate them into cells similar to pancreatic beta cells as a new type of treatment for type one diabetes mellitus. The results of this review will be helpful in the development of promising treatments and better control of diabetes mellitus.

Synthesis and characterization of novel fluoroterphenyls: self-assembly of low-molecular-weight fluorescent organogel.

Nucleophilic aromatic substitution has been highly para selective on a range of functionalized pentafluorobenzenes. Here, we demonstrate the utility of nucleophilic aromatic substitution chemistry for the preparation of fluorinated fluorescent low-molecular-weight organogels. The molecular design, synthesis and photophysical performance of a new class of thermoreversible and fluorescent low-molecular-weight organogels from para-alkoxy-functionalized fluorinated terphenyls are described. Both CuI-catalyzed decarboxylative cross-coupling and nucleophilic aromatic substitution chemistry were used for the preparation of those highly fluorinated gelators in high yields and excellent purity via simple filtration, from the corresponding potassium fluorobenzoate salts and aryl iodides. Various fluorinated symmetrical and asymmetrical para terphenyls were prepared with various para terminal alkoxy tails. Those fluorinated terphenyls were characterized using X-ray crystallography, differential scanning calorimetry, Fourier-transform infrared spectroscopy, as well as 1 H, 13 C, and 19 F nuclear magnetic resonance. UV-visible light absorbance and emission spectra of those new materials displayed a solvatochromic and solvatofluorochromic behaviour, respectively. Self-assembly of the produced fluorinated terphenyls occurred via cooperative π-π stacking and van der Waals interactions, which resulted in gelating various organic solvents. Scanning electron microscopy displayed the formation of fibre-like nanostructures. The cytotoxicity of some selected fluorinated symmetrical and asymmetrical para terphenyls was explored.