Coronavirus (SARS‐CoV‐2) as a global pandemic has attracted the attention of many scientific centers to find the right treatment. We expressed and purified the recombinant receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike (S) protein, and specific RBD aptamers were designed using SELEX method. RNAi targeting nucleocapsid phosphoprotein was synthesized and human lung cells were inoculated with aptamer‐functionalized lipid nanoparticles (LNPs) containing RNAi. The results demonstrated that RBD aptamer having K
D
values of 0.290 n
m
possessed good affinity. Based on molecular docking and efficacy prediction analysis, siRNA molecule was showed the best action. LNPs were appropriately functionalized by aptamer and contained RNAi molecules. Antiviral assay using q‐PCR and ELISA demonstrated that LNP functionalized with 35 µ
m
Apt and containing 30 n
m
RNAi/ml of cell culture had the best antiviral activity compared to other concentrations. Applied aptamer in the nanocarrier has two important functions. First, it can deliver the drug (RNAi) to the surface of epithelial cells. Second, by binding to the SARS‐CoV‐2 spike protein, it inhibits the virus entrance into cells. Our data reveal an interaction between the aptamer and the virus, and RNAi targeted the virus RNA. CT scan and the clinical laboratory tests in a clinical case study, a 36‐year old man who presented with severe SARS‐CoV‐2, demonstrated that inhalation of 10 mg Apt‐LNPs‐RNAi nebulized/day for six days resulted in an improvement in consolidation and ground‐glass opacity in lungs on the sixth day of treatment. Our findings suggest the treatment of SARS‐CoV‐2 infection through inhalation of Aptamer‐LNPs‐RNAi.
Developmental deficiency of somatic embryos and regeneration to plantlets, especially in the case of transformation, are major problems of somatic embryo regeneration in alfalfa. One of the ways to overcome these problems is the use of natural plant regulators and nutrients in the culture medium of somatic embryos. For investigating the influence of Cuscuta campestris extract on the efficiency of plant regeneration and transformation, chimeric tissue type plasminogen activator was transferred to explants using Agrobacterium tumefaciens, and transgenic plants were recovered using medium supplemented with different concentration of the extract. Transgenic plants were analyzed by PCR and RT-PCR. Somatic embryos of Medicago sativa L. developed into plantlets at high frequency level (52 %) in the maturation medium supplemented with 50 mg 1 -1 C. campestris extract as compared to the medium without extract (26 %). Transformation efficiency was 29.3 and 15.2 % for medium supplemented with dodder extract and without the extract, respectively. HPLC and GC/MS analysis of the extract indicated high level of ABA and some compounds such as Phytol, which can affect the somatic embryo maturation. The antibacterial assay showed that the extract was effective against some strains of A. tumefaciens. These results have provided a scientific basis for using of C. campestris extract as a good natural source of antimicrobial agents and plant growth regulator as well, that can be used in tissue culture of transgenic plants.
Vinblastine (VLB) is prescribed for a wide variety of cancers. Therefore, development of sensitive methods for early diagnosis is urgently required. In this work, a highly sensitive and label-free impedimetric biosensor was fabricated for the electrochemical detection of VLB. First, the gold nanoparticles (AuNPs) were electrodeposited on the surface of a glassy carbon electrode (GCE). 3-Mercaptopropionic acid (MPA) was self-assembled over the AuNPs. Then, tubulin (TUB), as a receptor, was covalently immobilized at the AuNPs/GCE surface via carbodiimide coupling reaction using N-(3 dimethylaminopropyl)-N'-ethyl carbodiimide (EDC) and N-hydroxy succinimide (NHS). The step-by-step modification process was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in the presence of a redox probe [Fe(CN)]. The VLB concentration was measured through the increase of impedance values in the corresponding specific binding of VLB and TUB. The increased electron-transfer resistance (R ) values were proportional to the value of VLB concentrations in the range of 0.4 to 65.0 nmol L with a detection limit of 8.4 × 10 nmol L (SN = 3). The practical analytical performance of the proposed method was demonstrated by determination of VLB in plant extracts and human serum samples with satisfactory recoveries.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.