Review on Approved and Inprogress COVID-19 Vaccines.

The last generation of Coronavirus named COVID-19 is responsible for the recent worldwide outbreak. Concerning the widespread and quick predominance, there is a critical requirement for designing appropriate vaccines to surmount this grave problem. Correspondingly, in this revision, COVID-19 vaccines (which are being developed until March 29th, 2021) are classified into specific and non-specific categories. Specific vaccines comprise genetic-based vaccines (mRNA, DNA), vector-based, protein/recombinant protein vaccines, inactivated viruses, live-attenuated vaccines, and novel strategies including microneedle arrays (MNAs), and nanoparticles vaccines. Moreover, specific vaccines such as BCG, MRR, and a few other vaccines are considered Non-specific. What is more, according to the significance of Bioinformatic sciences in the cutting-edge vaccine design and rapid outbreak of COVID-19, herein, Bioinformatic principles including reverse vaccinology, epitopes prediction/selection and, their further applications in the design of vaccines are discussed. Last but not least, safety, challenges, advantages, and future prospects of COVID-19 vaccines are highlighted.

Intraoperative pathologically-calibrated diagnosis of lymph nodes involved by breast cancer cells based on electrical impedance spectroscopy; a prospective diagnostic human model study.

BACKGROUND: Nodal status evaluation is a crucial step in determining prognostic factors and managing treatment strategies for breast cancer patients. Preoperative (CNB), intraoperative (SLNB), and even postoperative techniques (Formalin-Fixed Paraffin-Embedded sectioning, FFPE) have definite limitations of precision or sometimes are time-consuming for the result declaration. The primary purpose of this prospective study is to provide a precise complementary system for distinguishing lymph nodes (LNs) involved by cancerous cells in breast cancer patients intraoperatively. METHODS: The proposed system, Electrical Lymph Scoring(ELS), is designed based on the dielectric properties of the under-test LNs. The system has a needle-shaped 2-electrode probe entered into SLNs or ALNs dissected from patients through standard surgical guidelines. Impedance magnitude in f = 1 kH (Z1kHz) and Impedance Phase Slope in frequency ranges of 100 kHz-500 kHz (IPS) were then extracted from the impedance spectroscopy data in a cohort study of 77 breast cancer patients(totally 282 dissected LNs) who had been undergone surgery before (n = 55) or after (n = 22) chemical therapies (non-neoadjuvant or neoadjuvant chemotherapy). A new admittance parameter(Yn') also proposed for LN detection in neoadjuvant chemotherapy patients. RESULTS: Considering the permanent pathology result as the gold standard checked by two independent expert pathologists, a significant correlation was observed between the presence of cancerous cells in LNs and individual ranges of the ELS electrical responses. Compared with normal LNs containing fatty ambient and immune cells, LNs involved by cancerous clusters would reduce the Z1kHz and increase the IPS. These changes correlate with fat metabolism by cancer cells due to their Fatty Acid Oxidation (FAO) in LN, which results in different dielectric properties between high and low-fat content of normal and cancerous LNs, respectively. CONCLUSIONS: By finding the best correlation between our defined impedimetric parameters and pathological states of tested LNs, a real-time intraoperative detection approach was developed for highly-sensitive (92%, P<0.001) diagnosis of involved sentinel or axillary LNs. The impact of real-time intraoperative scoring of SLNs would make a pre-estimation about the necessity of excising further LNs to help the surgeon for less invasive surgery, especially in the absence of frozen-section equipment.

Myeloid-derived suppressor cells (MDSCs) in brain cancer: challenges and therapeutic strategies.

The most fatal malignancy of the central nervous system (CNS) is glioblastoma. Brain cancer is a 'cold' tumor because of fewer immunoregulatory cells and more immunosuppressive cells. Due to the cold nature of brain cancers, conventional treatments which are used to manage glioma patients show little effectiveness. Glioma patients even showed resistance to immune checkpoint blockade (ICB) and no significant efficacy. It has been shown that myeloid-derived suppressor cells (MDSCs) account for approximately 30-50% of the tumor mass in glioma. This study aimed to review MDSC function in brain cancer, as well as possible treatments and related challenges. In brain cancer and glioma, several differences in the context of MDSCs have been reported, including disagreements about the MDSC subtype that has the most inhibitory function in the brain, or inhibitory function of regulatory B cells (Bregs). There are also serious challenges in treating glioma patients. In addition to the cold nature of glioma, there are reports of an increase in MDSCs following conventional chemotherapy treatments. As a result, targeting MDSCs in combination with other therapies, such as ICB, is essential, and recent studies with the combination therapy approach have shown promising therapeutic effects in brain cancer.

A label-free graphene-based impedimetric biosensor for real-time tracing of the cytokine storm in blood serum; suitable for screening COVID-19 patients.

Concurrent with the pandemic announcement of SARS-CoV-2 infection by the WHO, a variety of reports were published confirming the cytokine storm as the most mortal effect of the virus on the infected patients. Hence, cytokine storm as an evidenced consequence in most of the COVID-19 patients could offer a promising opportunity to use blood as a disease progression marker. Here, we have developed a rapid electrochemical impedance spectroscopy (EIS) sensor for quantifying the overall immune activity of the patients. Since during the cytokine storm many types of cytokines are elevated in the blood, there is no need for specific detection of a single type of cytokine and the collective behavior is just measured without any electrode functionalization. The sensor includes a monolayer graphene on a copper substrate as the working electrode (WE) which is able to distinguish between the early and severe stage of the infected patients. The charge transfer resistance (R CT) in the moderate and severe cases varies about 65% and 138% compared to the normal groups, respectively and a specificity of 77% and sensitivity of 100% based on ELISA results were achieved. The outcomes demonstrate a significant correlation between the total mass of the three main hypercytokinemia associated cytokines including IL-6, TNF-α and IFN-γ in patients and the R CT values. As an extra application, the biosensor's capability for diagnosis of COVID-19 patients was tested and a sensitivity of 92% and specificity of 50% were obtained compared to the RT-PCR results.

Spectroscopic, molecular docking and molecular dynamic simulation studies on the complexes of ß-lactoglobulin, safranal and oleuropein.

Herbal bioactive compounds have captured pronounced attention considering their health-promoting effects as well as their functional properties. In this study, the binding mechanism between milk protein bovine ß-lactoglobulin (ß-LG), oleuropein (OLE) and safranal (SAF) found in olive leaf extract and saffron, respectively via spectroscopic and in silico studies. Fluorescence quenching information exhibited that interactions with both ligands were spontaneous and hydrophobic interactions were dominant. Also, the CD spectroscopy results demonstrated the increase in ß-sheet structure and decrease in the α-helix content for both ligands. Size of ß-LG-OLE complex was higher than ß-LG-SAF due to the conformation and larger molecular size. Molecular docking and simulation studies revealed that SAF and OLE bind in the central calyx of ß-LG and the surface of ß-LG next to hydrophobic residues. Lastly, OLE formed a more stabilized complex compared to SAF based on the molecular dynamic simulation results.

Plasmon-induced transparency based on a triangle cavity coupled with an ellipse-ring resonator.

In this paper, a novel compact plasmonic system is introduced to realize the phenomenon of plasmon-induced transparency. The proposed device consists of a triangle defect coupled with an ellipse-ring resonator based on a metal-insulator-metal platform. By the finite-difference time-domain method, the transmission characteristics are numerically studied in detail. In order to verify the simulation results, the coupled mode theory is utilized. In the following, the effect of geometrical parameters, namely, the major and minor radii of the ellipse-ring and the gap between cavities, are investigated. Moreover, the fundamental factors of transmission spectra including intrinsic Drude loss and refractive index of dielectric region are studied. As a result, the transmission peak is obtained near 70% and the full width at half-maximum is close to 28 nm. The sensitivity and figure of merit of the proposed structure are 860 nm/RIU and 31.6 RIU-1, respectively. The mentioned compact structure has the ability and potential to be used in integrated optical circuits like slow light devices, nanoscale filters and nanosensors.

Analysis and investigation of temperature and hydrostatic pressure effects on optical characteristics of multiple quantum well slow light devices.

This paper represents the influences of temperature and hydrostatic pressure variations on GaAs/AlGaAs multiple quantum well slow light systems based on coherence population oscillations. An analytical model in non-integer dimension space is used to study the considerable effects of these parameters on optical properties of the slow light apparatus. Exciton oscillator strength and fractional dimension constants have special roles on the analytical model in fractional dimension. Hence, the impacts of hydrostatic pressure and temperature on exciton oscillator strength and fractional dimension quantity are investigated theoretically in this paper. Based on the achieved results, temperature and hydrostatic pressure play key roles on optical parameters of the slow light systems, such as the slow down factor and central energy of the device. It is found that the slope and value of the refractive index real part change with alterations of temperature and hydrostatic pressure in the range of 5-40 deg of Kelvin and 1 bar to 2 kbar, respectively. Thus, the peak value of the slow down factor can be adjusted by altering these parameters. Moreover, the central energy of the device shifts when the hydrostatic pressure is applied to the slow light device or temperature is varied. In comparison with previous reported experimental results, our simulations follow them successfully. It is shown that the maximum value of the slow down factor is estimated close to 5.5×104 with a fine adjustment of temperature and hydrostatic pressure. Meanwhile, the central energy shift of the slow light device rises up to 27 meV, which provides an appropriate basis for different optical devices in which multiple quantum well slow light is one of their essential subsections. This multiple quantum well slow light device has potential applications for use as a tunable optical buffer and pressure/temperature sensors.