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The global spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) since 2019 has led to a continuous evolution of viral variants, with the latest concern being the Omicron (B.1.1.529) variant. In this study, classical molecular dynamics simulations were conducted to elucidate the biophysical aspects of the Omicron spike protein's receptor-binding domain (RBD) in its interaction with human angiotensin-converting enzyme 2 (hACE2) and a neutralizing antibody, comparing it to the wildtype (WT). To model the Omicron variant, 15 in silico mutations were introduced in the RBD region of WT (retrieved from PDB). The simulations of WT spike-hACE2 and Omicron spike-hACE2 complexes revealed comparable binding stability and dynamics. Notably, the Q493R mutation in the Omicron spike increased interactions with hACE2, particularly with ASP38 and ASP355. Additionally, mutations such as N417K, T478K, and Y505H contributed to enhanced structural stability in the Omicron variant. Conversely, when comparing WT with Omicron in complex with a neutralizing antibody, simulation results demonstrated poorer binding dynamics and stability for the Omicron variant. The E484K mutation significantly decreased binding interactions, resulting in an overall decrease in binding energy (∼-57 kcal/mol) compared to WT (∼-84 kcal/mol). This study provides valuable molecular insights into the heightened infectivity of the Omicron variant, shedding light on the specific mutations influencing its interactions with hACE2 and neutralizing antibodies.

BackgroundThe Pediatric Emergency Medicine (PEM) Point-of-care Ultrasound (POCUS) Network (P2Network) was established in 2014 to provide a platform for international collaboration among experts, including multicenter research. The objective of this study was to use expert consensus to identify and prioritize PEM POCUS topics, to inform future collaborative multicenter research.MethodsOnline surveys were administered in a two-stage, modified Delphi study. A steering committee of 16 PEM POCUS experts was identified within the P2Network, with representation from the United States, Canada, Italy, and Australia. We solicited the participation of international PEM POCUS experts through professional society mailing lists, research networks, social media, and "word of mouth." After each round, responses were refined by the steering committee before being reissued to participants to determine the ranking of all the research questions based on means and to identify the high-level consensus topics. The final stage was a modified Hanlon process of prioritization round (HPP), which emphasized relevance, impact, and feasibility.ResultsFifty-four eligible participants (16.6%) provided 191 items to Survey 1 (Round 1). These were refined and consolidated into 52 research questions by the steering committee. These were issued for rating in Survey 2 (Round 2), which had 45 participants. At the completion of Round 2, all questions were ranked with six research questions reaching high-level consensus. Thirty-one research questions with mean ratings above neutral were selected for the HPP round. Highly ranked topics included clinical applications of POCUS to evaluate and manage children with shock, cardiac arrest, thoracoabdominal trauma, suspected cardiac failure, atraumatic limp, and intussusception.ConclusionsThis consensus study has established a research agenda to inform future international multicenter PEM POCUS trials. This study has highlighted the ongoing need for high-quality evidence for PEM POCUS applications to guide clinical practice.

Abstract Background Point-of-Care-Ultrasound (POCUS) curricula have rapidly expanded in undergraduate medical education (UME). However, the assessments used in UME remain variable without national standards. This scoping review characterizes and categorizes current assessment methods using Miller’s pyramid for skills, performance, and competence of POCUS in UME. A structured protocol was developed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). A literature search of MEDLINE was performed from January 1, 2010, to June 15, 2021. Two independent reviewers screened all titles and abstracts for articles that met inclusion criteria. The authors included all POCUS UME publications in which POCUS-related knowledge, skills, or competence were taught and objectively assessed. Articles were excluded if there were no assessment methods used, if they exclusively used self-assessment of learned skills, were duplicate articles, or were summaries of other literature. Full text analysis and data extraction of included articles were performed by two independent reviewers. A consensus-based approach was used to categorize data and a thematic analysis was performed. Results A total of 643 articles were retrieved and 157 articles met inclusion criteria for full review. Most articles (n = 132; 84%) used technical skill assessments including objective structured clinical examinations (n = 27; 17%), and/or other technical skill-based formats including image acquisition (n = 107; 68%). Retention was assessed in n = 98 (62%) studies. One or more levels of Miller’s pyramid were included in 72 (46%) articles. A total of four articles (2.5%) assessed for students’ integration of the skill into medical decision making and daily practice. Conclusions Our findings demonstrate a lack of clinical assessment in UME POCUS that focus on integration of skills in daily clinical practice of medical students corresponding to the highest level of Miller’s Pyramid. There exists opportunities to develop and integrate assessment that evaluate higher level competencies of POCUS skills of medical students. A mixture of assessment methods that correspond to multiple levels of Miller’s pyramid should be used to best assess POCUS competence in UME.

Background: Point of Care Ultrasound (POCUS) is an important tool in pediatric emergency medicine. In neonatal intensive care medicine ultrasound is often used to evaluate the brains of sick neonates. In theory, POCUS could be used in the ED in young children to evaluate the brain for abnormal pathology. Objectives: To examine the ability of PEM faculty to use brain POCUS to identify clinically significant brain injuries in children with head injuries and/or abnormal neurological exams, and generate sensitivity and specificity of brain POCUS in assessing such findings. Methods: This study used a convenience sample of patients seen in a tertiary care pediatric centre who required a CT head. A team of physicians who were trained at a workshop for brain POCUS were on call to perform the POCUS while being blinded to the results of the CT. Results: 21 children were enrolled in the study. Five (24%) of the patients had a CT that was positive for intracranial bleeds. Of the 5 patients with a positive CT, 3 had a brain POCUS scan that was also positive. The two false negative brain POCUS scans were on patients with small bleeds (no surgical intervention required) on CT, as reported by radiology. The sensitivity of brain POCUS was 60% (CI 15% - 95%) with a specificity of 94% (CI 70%-100%). The diagnostic accuracy of brain POCUS was 86% (CI 64% - 97%). Conclusion: This small proof of concept study shows that brain POCUS is an imaging modality with reasonable sensitivity and specificity in identifying intracranial pathologies that are present on CT. Its use may be most beneficial to expedite definitive imaging and subspeciality involvement.

Simple Summary: Mortalin is a heat shock protein 70 stress chaperone family member with variable subcellular localization in normal and cancer cells. It is an essential protein with multiple functions that support and promote proliferation, endorsed by its enriched expression in various cancers. Due to its prime involvement in stress adaptation and carcinogenesis, regulating Mortalin expression and function is a viable therapeutic avenue. Upregulation of stress chaperone Mortalin has been closely linked to the malignant transformation of cells, tumorigenesis, the progression of tumors to highly aggressive stages, metastasis, drug resistance, and relapse. Various in vitro and in vivo assays have provided evidence of the critical role of Mortalin upregulation in promoting cancer cell characteristics, including proliferation, migration, invasion, and the inhibition of apoptosis, a consistent feature of most cancers. Given its critical role in several steps in oncogenesis and multi-modes of action, Mortalin presents a promising target for cancer therapy. Consequently, Mortalin inhibitors are emerging as potential anti-cancer drugs. In this review, we discuss various inhibitors of Mortalin (peptides, small RNAs, natural and synthetic compounds, and antibodies), elucidating their anti-cancer potentials. [ABSTRACT FROM AUTHOR]

Simple Summary: The inactivation of apoptotic signaling by inhibitors of apoptosis proteins (IAPs) is one of the important hallmarks of cancer cells. Survivin, a 16.5 kDa member of the IAP family, is commonly enriched in many cancers and is a potential therapeutic target. We investigated the Survivin-targeting potential of Withaferin-A (Wi-A) and Withanone (Wi-N), two major withanolides from Withania somnifera (Ashwagandha), using computational assays. The results were validated in various in vitro experimental assays using Wi-A-rich extracts from Ashwagandha leaves, suggesting their use as an important bioresource for cancer drug development. Survivin, a member of the IAP family, functions as a homodimer and inhibits caspases, the key enzymes involved in apoptosis. Several Survivin inhibitors, including YM-155, Debio1143, EM1421, LQZ-7I, and TL32711, have emerged as potential anticancer drugs awaiting validation in clinical trials. Due to the high cost and adverse side effects of synthetic drugs, natural compounds with similar activity have also been in demand. In this study, we conducted molecular docking assays to evaluate the ability of Wi-A and Wi-N to block Survivin dimerization. We found that Wi-A, but not Wi-N, can bind to and prevent the homodimerization of Survivin, similar to YM-155. Therefore, we prepared a Wi-A-rich extract from Ashwagandha leaves (Wi-AREAL). Experimental analyses of human cervical carcinoma cells (HeLa and ME-180) treated with Wi-AREAL (0.05–0.1%) included assessments of viability, apoptosis, cell cycle, migration, invasion, and the expression levels (mRNA and protein) of molecular markers associated with these phenotypes. We found that Wi-AREAL led to growth arrest mediated by the upregulation of p21WAF1 and the downregulation of several proteins (CDK1, Cyclin B, pRb) involved in cell cycle progression. Furthermore, Wi-AREAL treatment activated apoptosis signaling, as evidenced by reduced PARP-1 and Bcl-2 levels, increased procaspase-3, and elevated Cytochrome C. Additionally, treating cells with a nontoxic low concentration (0.01%) of Wi-AREAL inhibited migration and invasion, as well as EMT (epithelial–mesenchymal transition) signaling. By combining computational and experimental approaches, we demonstrate the potential of Wi-A and Wi-AREAL as natural inhibitors of Survivin, which may be helpful in cancer treatment. [ABSTRACT FROM AUTHOR]

Genetic mutations in p53 are frequently associated with many types of cancers that affect its stability and activity through multiple ways. The Ser46 residue present in the transactivation domain2 (TAD2) domain of p53 undergoes phosphorylation that blocks its degradation by MDM2 and leads to cell cycle arrest/apoptosis/necrosis upon intrinsic or extrinsic stresses. On the other hand, unphosphorylated p53 mutants escape cell arrest or death triggered by these molecular signaling axes and lead to carcinogenesis. Phosphorylation of Ser in the TAD2 domain of p53 mediates its interactions with transcription factor p62, yielding transcriptional activation of downstream pro-apoptotic genes. The p53 phosphorylation causes string-like elongated conformation that increases its binding affinity with the PH domain of p62. On the other hand, lack of phosphorylation causes helix-like motifs and low binding affinity to p62. We undertook molecular simulation analyses to investigate the potential of some natural small molecules (Withanone (Wi-N) & Withaferin-A (Wi-A) from Ashwagandha; Cucurbitacin-B (Cuc-B) from bitter Cucumber; and Caffeic acid phenethyl ester (CAPE) and Artepillin C (ARC) from honeybee propolis) to interact with p62-binding region of p53 and restore its wild-type activity. We found that Wi-N, Wi-A, and Cuc-B have the potential to restore p53-p62 interaction for phosphorylation-deficient p53 mutants. Wi-N, in particular, caused a reversal of the α-helical structure into an elongated string-like conformation similar to the wild-type p53. These data suggested the use of these natural compounds for the treatment of p53Ser46 mutant harbouring cancers. We also compared the efficiency of Wi-N, Wi-A, Cuc-B, CAPE, and ARC to abrogate Mortalin-p53 binding resulting in nuclear translocation and reactivation of p53 function and provide experimental evidence to the computational analysis. Taken together, the use of these small molecules for reactivation of p53 in cancer cells is suggested.

Mortalin, a heat shock family protein enriched in cancer cells, is known to inactivate tumor suppressor protein p53. Abrogation of mortalin-p53 interaction and reactivation of p53 has been shown to trigger growth arrest/apoptosis in cancer cells and hence, suggested to be useful in cancer therapy. In this premise, we earlier screened a chemical library to identify potential disruptors of mortalin-p53 interaction, and reported two novel synthetic small molecules (5-[1-(4-methoxyphenyl) (1,2,3,4-tetraazol-5-yl)]-4-phenylpyrimidine-2-ylamine) and (4-[(1E)-2-(2-phenylindol-3-yl)-1-azavinyl]-1,2,4-triazole) called Mortaparib and MortaparibPlus, respectively. These compounds were shown to possess anticancer activity that was mediated through targeting mortalin and PARP1 proteins, essential for cancer cell survival and proliferation. Here, we report characterization of the third compound, {4-[(4-amino-5-thiophen-2-yl-1,2,4-triazol-3-yl)sulfanylmethyl]-N-(4-methoxyphenyl)-1,3-thiazol-2-amine}, isolated in the same screening. Extensive computational and molecular analyses suggested that the new compound has the capability to interact with mortalin, p53, and PARP1. We provide evidence that this new compound, although required in high concentration as compared to the earlier two compounds (Mortaparib and MortaparibPlus) and hence called MortaparibMild, also downregulates mortalin and PARP1 expression and functions in multiple ways impeding cancer cell proliferation and migration characteristics. MortaparibMild is a novel candidate anticancer compound that warrants further experimental and clinical attention.

This paper discusses the impact of a series of psychological phenomena on the U.S. response to COVID-19, focusing on forecasts of cases and deaths. The specific phenomena comprise unrealistic optimism bias, overconfidence, anchoring and adjustment, representativeness, motivated reasoning, and groupthink.