Density estimation of SARS-CoV2 spike proteins using super pixels segmentation technique.

The worldwide outbreak of COVID-19 disease was caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2). The existence of spike proteins, which allow these viruses to infect host cells, is one of the distinctive biological traits of various prior viruses. As a result, the process by which these viruses infect people is largely dependent on spike proteins. The density of SARS-CoV-2 spike proteins must be estimated to better understand and develop diagnostics and vaccines against the COVID-19 pandemic. CT scans and X-rays have three issues: frosted glass, consolidation, and strange roadway layouts. Each of these issues can be graded separately or together. Although CT scan is sensitive to COVID-19, it is not very specific. Therefore, patients who obtain these results should have more comprehensive clinical and laboratory tests to rule out other probable reasons. This work collected 586 SARS-CoV 2 transmission electron microscopy (TEM) images from open source for density estimation of virus spike proteins through a segmentation approach based on the superpixel technique. As a result, the spike density means of SARS-CoV2 and SARS-CoV were 21,97 nm and 22,45 nm, respectively. Furthermore, in the future, we aim to include this model in an intelligent system to enhance the accuracy of viral detection and classification. Moreover, we can remotely connect hospitals and public sites to conduct environmental hazard assessments and data collection.

Human Body Performance with COVID-19 Affectation According to Virus Specification Based on Biosensor Techniques.

Life was once normal before the first announcement of COVID-19's first case in Wuhan, China, and what was slowly spreading became an overnight worldwide pandemic. Ever since the virus spread at the end of 2019, it has been morphing and rapidly adapting to human nature changes which cause difficult conundrums in the efforts of fighting it. Thus, researchers were steered to investigate the virus in order to contain the outbreak considering its novelty and there being no known cure. In contribution to that, this paper extensively reviewed, compared, and analyzed two main points; SARS-CoV-2 virus transmission in humans and detection methods of COVID-19 in the human body. SARS-CoV-2 human exchange transmission methods reviewed four modes of transmission which are Respiratory Transmission, Fecal-Oral Transmission, Ocular transmission, and Vertical Transmission. The latter point particularly sheds light on the latest discoveries and advancements in the aim of COVID-19 diagnosis and detection of SARS-CoV-2 virus associated with this disease in the human body. The methods in this review paper were classified into two categories which are RNA-based detection including RT-PCR, LAMP, CRISPR, and NGS and secondly, biosensors detection including, electrochemical biosensors, electronic biosensors, piezoelectric biosensors, and optical biosensors.

Detection of COVID-19 Virus on Surfaces Using Photonics: Challenges and Perspectives.

The propagation of viruses has become a global threat as proven through the coronavirus disease (COVID-19) pandemic. Therefore, the quick detection of viral diseases and infections could be necessary. This study aims to develop a framework for virus diagnoses based on integrating photonics technology with artificial intelligence to enhance healthcare in public areas, marketplaces, hospitals, and airfields due to the distinct spectral signatures from lasers' effectiveness in the classification and monitoring of viruses. However, providing insights into the technical aspect also helps researchers identify the possibilities and difficulties in this field. The contents of this study were collected from six authoritative databases: Web of Science, IEEE Xplore, Science Direct, Scopus, PubMed Central, and Google Scholar. This review includes an analysis and summary of laser techniques to diagnose COVID-19 such as fluorescence methods, surface-enhanced Raman scattering, surface plasmon resonance, and integration of Raman scattering with SPR techniques. Finally, we select the best strategies that could potentially be the most effective methods of reducing epidemic spreading and improving healthcare in the environment.

Pharmacokinetic comparison between Tanreqing Capsules Substitute and Tanreqing Capsules in rats by LC-MS/MS / 中国中药杂志

Due to the limited resource of bear bile powder, the major raw material of Tanreqing Capsules(TRQ), cultured bear bile powder is used as a replacement to develop the Tanreqing Capsules Substitute(TRQS). An LC-MS/MS method was established in this study for simultaneous quantitation of 8 compounds from TRQS in rat plasma: tauroursodeoxycholic acid(TUDCA), taurocheno-deoxycholic acid(TCDCA), ursodeoxycholic acid(UDCA), chenodeoxycholic acid(CDCA), ferulic acid, wogonoside, baicalin, and forsythoside A. Thereby, the pharmacokinetic behaviors of TRQ and TRQS were evaluated. Concentration of endogenous compounds TUDCA, TCDCA, UDCA, and CDCA was determined with the stable isotope surrogate analytes: D4-TUDCA, D4-TCDCA, D4-UDCA, and D4-CDCA. Plasma samples were extracted by acetonitrile-induced protein precipitation. The LC conditions are as follows: Waters BEH C_(18) column(2.1 mm×100 mm, 1.7 μm), mobile phase of 10 mmol·L~(-1) ammonium formate aqueous solution(containing 0.01% formic acid) and acetonitrile-methanol mixture(1∶5). MS conditions are as below: multiple reaction monitoring(MRM), ESI~(+/-). Concentration of UDCA, CDCA, TUDCA, and TCDCA was corrected with a response factor, which is the ratio between the responses recorded for the surrogate and the authentic analyte at the equal concentration. Each of the plasma components showed good linearity(r > 0.995 1). Accuracy and precision met the criteria(inter-day RSD<7.0%, RE 89.98%-112.0%; intra-day RSD<12%, RE 90.41%-111.2%). The recovery was 64.83%-119.9% and matrix effect was 87.15%-113.8%. The validated method was applied for pharmacokinetic study of TRQS and TRQ(po, 0.94 g·kg~(-1)). There was no significant difference in C_(max) and AUC_(0-24 h) of baicalin, UDCA, TUDCA, and TCDCA between the two groups, indicating similar pharmacokinetic behaviors between TRQS and TRQ in rats.

An Analysis Review of Detection Coronavirus Disease 2019 (COVID-19) Based on Biosensor Application.

Timely detection and diagnosis are essentially needed to guide outbreak measures and infection control. It is vital to improve healthcare quality in public places, markets, schools and airports and provide useful insights into the technological environment and help researchers acknowledge the choices and gaps available in this field. In this narrative review, the detection of coronavirus disease 2019 (COVID-19) technologies is summarized and discussed with a comparison between them from several aspects to arrive at an accurate decision on the feasibility of applying the best of these techniques in the biosensors that operate using laser detection technology. The collection of data in this analysis was done by using six reliable academic databases, namely, Science Direct, IEEE Xplore, Scopus, Web of Science, Google Scholar and PubMed. This review includes an analysis review of three highlights: evaluating the hazard of pandemic COVID-19 transmission styles and comparing them with Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) to identify the main causes of the virus spreading, a critical analysis to diagnose coronavirus disease 2019 (COVID-19) based on artificial intelligence using CT scans and CXR images and types of biosensors. Finally, we select the best methods that can potentially stop the propagation of the coronavirus pandemic.

Simultaneous determination of fosaprepitant and its metabolite aprepitant in human plasma by liquid chromatography-tandem mass spectrometry / 药学学报

An LC-MS/MS method was developed for the simultaneous determination of fosaprepitant and aprepitant in human plasma, and applied to a pharmacokinetic study of 150 mg fosaprepitant dimeglumine injection to 12 Chinese healthy volunteers. The analytes and internal standards were extracted from plasma by protein precipitation with acetonitrile and separated on a Cortex C18+ (50 mm×2.1 mm, 2.7 μm) column using a gradient elution procedure. Mass spectrometry was performed in negative MRM mode, and parent-to-produce transitions were as follows:m/z 613.1→78.9 for fosaprepitant, m/z 617.0→78.9 for d4-fosaprepitant, m/z 533.2→275.1 for aprepitant and m/z 537.2→279.1 for d4-aprepitant. Plasma sample was basified to stabilize fosaprepitant. The standard curves were demonstrated to be liner in the range of 15.0 to 6 000 ng·mL-1 for fosaprepitant and 10.0 to 4 000 ng·mL-1 for aprepitant. The intra-day precisions and inter-day precisions and accuracy were within the acceptable limits for all concentrations.