In only a few months after initial discovery in Wuhan, China, SARS-CoV-2 and the associated coronavirus disease 2019 (COVID-19) have become a global pandemic causing significant mortality and ...morbidity and implementation of strict isolation measures. In the absence of vaccines and effective therapeutics, reliable serological testing must be a key element of public health policy to control further spread of the disease and gradually remove quarantine measures. Serological diagnostic tests are being increasingly used to provide a broader understanding of COVID-19 incidence and to assess immunity status in the population. However, there are discrepancies between claimed and actual performance data for serological diagnostic tests on the market. In this study, we conducted a review of independent studies evaluating the performance of SARS-CoV-2 serological tests. We found significant variability in the accuracy of marketed tests and highlight several lab-based and point-of-care rapid serological tests with high levels of performance. The findings of this review highlight the need for ongoing independent evaluations of commercialized COVID-19 diagnostic tests.
COVID-19 pandemic will continue to pose a major public health threat until vaccination-mediated herd immunity is achieved. Most projections predict vaccines will reach a large subset of the ...population late in 2021 or early 2022. In the meantime, countries are exploring options to remove strict lockdown measures and allow society and the economy to return to normal function. One possibility is to expand on existing COVID-19 testing strategies by including large-scale rapid point-of-care diagnostic tests (POCTs). Currently, there is significant variability in performance and features of available POCTs, making selection and procurement of an appropriate test for specific use case difficult. In this review, we have used the World Health Organization's (WHO) recently published target product profiles (TPPs) for specific use cases of COVID-19 diagnostic tests to screen for top-performing POCTs on the market. Several POCTs, based on clinical sensitivity/specificity, the limit of detection, and time to results, which meet WHO TPP criteria for direct detection of SARS-CoV-2 (acute infection) or indirect diagnosis of past infection (host antibodies), are highlighted here.
Hallucinations limit widespread therapeutic use of psychedelics as rapidly acting antidepressants. Here we profiled the non-hallucinogenic lysergic acid diethylamide (LSD) analog 2-bromo-LSD ...(2-Br-LSD) at more than 33 aminergic G protein-coupled receptors (GPCRs). 2-Br-LSD shows partial agonism at several aminergic GPCRs, including 5-HT2A, and does not induce the head-twitch response (HTR) in mice, supporting its classification as a non-hallucinogenic 5-HT2A partial agonist. Unlike LSD, 2-Br-LSD lacks 5-HT2B agonism, an effect linked to cardiac valvulopathy. Additionally, 2-Br-LSD produces weak 5-HT2A β-arrestin recruitment and internalization in vitro and does not induce tolerance in vivo after repeated administration. 2-Br-LSD induces dendritogenesis and spinogenesis in cultured rat cortical neurons and increases active coping behavior in mice, an effect blocked by the 5-HT2A-selective antagonist volinanserin (M100907). 2-Br-LSD also reverses the behavioral effects of chronic stress. Overall, 2-Br-LSD has an improved pharmacological profile compared with LSD and may have profound therapeutic value for mood disorders and other indications.
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•2-Br-LSD is a 5-HT2A partial agonist but lacks 5-HT2B agonism•2-Br-LSD lacks head-twitch responses and tolerance; blocks psychedelics•2-Br-LSD treatment promotes neuronal structural plasticity dependent on 5-HT2A•2-Br-LSD produces active coping behavior and reverses chronic stress deficits
Lewis et al. perform an extensive pharmacological characterization of 2-Br-LSD, finding distinct aminergic GPCR polypharmacology, including 5-HT2A partial agonism and lack of psychedelic-like effects in vivo. Further, 2-Br-LSD induces dendritogenesis and spinogenesis in vitro while promoting active coping behavior in vivo, effects dependent on 5-HT2A activation.
Up-regulation of the cytoskeleton linker protein ezrin frequently occurs in aggressive cancer types and is closely linked with metastatic progression. However, the underlying molecular mechanisms ...detailing how ezrin is involved in the invasive and metastatic phenotype remain unclear. Here we report a novel function of ezrin in regulating focal adhesion (FA) and invadopodia dynamics, two key processes required for efficient invasion to occur. We show that depletion of ezrin expression in invasive breast cancer cells impairs both FA and invadopodia turnover. We also demonstrate that ezrin-depleted cells display reduced calpain-mediated cleavage of the FA and invadopodia-associated proteins talin, focal adhesion kinase (FAK), and cortactin and reduced calpain-1-specific membrane localization, suggesting a requirement for ezrin in maintaining proper localization and activity of calpain-1. Furthermore, we show that ezrin is required for cell directionality, early lung seeding, and distant organ colonization but not primary tumor growth. Collectively our results unveil a novel mechanism by which ezrin regulates breast cancer cell invasion and metastasis.
Limited understanding of the cancer biology of metastatic sites is a major factor contributing to poor outcomes in cancer patients. The regional lymph nodes are the most common site of metastasis in ...most solid cancers and their involvement is a strong predictor of relapse in breast cancer (BC). We have previously shown that ezrin, a cytoskeletal-membrane linker protein, is associated with lymphovascular invasion and promotes metastatic progression in BC. However, the efficacy of pharmacological inhibition of ezrin in blocking cancer cell migration and metastasis remains unexplored in BC.
We quantified ezrin expression in a BC tissue microarray (n = 347) to assess its correlation with risk of relapse. Next, we developed a quantitative intravital microscopy (qIVM) approach, using a syngeneic lymphatic reporter mouse tumor model, to investigate the effect of systemic ezrin inhibition on cancer cell migration and metastasis.
We show that ezrin is expressed at significantly higher levels in lymph node metastases compared to matched primary tumors, and that a high tumor ezrin level is associated with increased risk of relapse in BC patients with regional disease. Using qIVM, we observe a subset of cancer cells that retain their invasive and migratory phenotype at the tumor-draining lymph node. We further show that systemic inhibition of ezrin, using a small molecule compound (NSC668394), impedes the migration of cancer cells in vivo. Furthermore, systemic ezrin inhibition leads to reductions in metastatic burden at the distal axillary lymph node and lungs.
Our findings demonstrate that the tumor ezrin level act as an independent biomarker in predicting relapse and provide a rationale for therapeutic targeting of ezrin to reduce the metastatic capacity of cancer cells in high-risk BC patients with elevated ezrin expression.
ABSTRACT
The ability to generate or repair injured tissue is essential to the continuity of human life. As in all other organs, wound healing in the skin is a dynamic process involving tissue ...response to different types of insults. This process involves a continuous sequence of signals and responses in which platelets, fibroblasts, epithelial, endothelial, and immune cells come together outside their usual domains to orchestrate a very complex event that results in tissue repair. These signals, which are mainly growth factors and cytokines, orchestrate the initiation, continuation, and termination of wound healing. An imbalance in the synthesis and release of these cytokines and growth factors at the wound site, therefore, may result in either retarded wound healing, as is seen in diabetic patients and the elderly population, or overhealing wounds such as fibroproliferative disorders frequently seen following surgical incision, traumatic wounds, and severe electrical and thermal injury. In general, regardless of the site of injury, in any phase of the dynamic healing process, a fine balance between synthesis of extracellular matrix and degradation by a large family of enzymes, known as matrix metalloproteinases, is required for maintaining the structural integrity of healing tissue. The availability of new models such as organotypic co‐culture systems have allowed us to gain new insight into the cell–cell interactions at both cellular and molecular levels. Recent evidence indicates that mesenchymal–epithelial interactions play a critical role in regulation of skin homeostasis and this cross‐talk is mediated by soluble factors acting as autocrine/paracrine regulators of fibroblast and keratinocyte growth, function, and differentiation. In this review we address the question of how keratinocyte–fibroblast interaction plays a role in controlling the expression of key extracellular matrix molecules such as matrix metalloproteinases, which are critical in the healing process following any types of insults to the skin.
Introduction
The cytoskeletal protein ezrin is upregulated in many cancer types and is strongly associated with poor patient outcome. While the clinical and prognostic value of ezrin has been ...previously evaluated in breast cancer, most studies to date have been conducted in smaller cohorts (less than 500 cases) or have focused on specific disease characteristics. The current study is the largest of its kind to evaluate ezrin both at the protein and mRNA levels in early‐stage breast cancer patients using the Nottingham (n = 1094) and METABRIC (n = 1980) cohorts, respectively.
Results
High expression of ezrin was significantly associated with larger tumour size (p = 0.027), higher tumour grade (p < 0.001), worse Nottingham Prognostic Index prognostic group (p = 0.011) and HER2‐positive status (p = 0.001). High ezrin expression was significantly associated with adverse survival of breast cancer patients (p < 0.001) and remained associated with survival in multivariate Cox‐regression analysis (p = 0.018, hazard ratio (HR) = 1.343, 95% confidence interval (CI) = 1.051–1.716) when potentially confounding factors were included. High ezrin expression was significantly associated with adverse survival of patients whose tumours were categorised as receptor (oestrogen receptor (ER), progesterone receptor (PgR) or HER2) positive (p < 0.001) in comparison to those categorised as triple‐negative breast cancer (p = 0.889). High expression of ezrin mRNA (VIL2) in the METABRIC cohort was also significantly associated with adverse survival of breast cancer patients (p < 0.001).
Conclusion
Retrospective analyses show that ezrin is an independent prognostic marker, with higher expression associated with shortened survival in receptor‐positive (ER, PgR or HER2) patients. Ezrin expression is associated with more aggressive disease and may have clinical utility as a biomarker of patient prognosis in early‐stage breast cancer.
Ezrin expression is associated with clinical outcome of breast cancer patients.
ABSTRACT
Bacterial burden significantly interferes with the healing process in chronic ulcers. Nitric oxide (NO) plays a key role in regulating skin's response to infection and wound healing. In ...previous studies, we demonstrated that exogenous NO gas (gNO) at 200 parts per million (ppm) exhibits potent antimicrobial effects against a representative range of pathogens. The aim of the present study is to explore the antimicrobial properties of gNO in vivo and to determine skin cells' sensitivity to the cytotoxic effects of gNO. To test gNO's antimicrobial effects, full‐thickness wounds were infected with Staphylococcus aureus on the dorsal skin surface of New Zealand White rabbit and treated with 200 ppm gNO for 8 hours/day for 3 consecutive days. Significant reduction in wound bacterial content was observed in the presence of gNO. In a separate experiment, primary cultures of human fibroblasts, keratinocytes, and endothelial cells were established to test gNO's cytotoxicity in the skin. Methyl thiazolyl tetrazolium proliferation assays demonstrated that human skin cells, unlike bacterial cells, exhibited significant resistance toward gNO cytotoxicity. In vitro migration studies on keratinocytes and endothelial cells revealed that gNO treatment does not seem to interfere with reepithelialization and angiogenesis during the process of wound healing. Following 24 hours of gNO treatment, fibroblasts expressed significantly higher levels of procollagen and, to a lesser degree, a decrease in matrix metalloproteinase ‐1 mRNA. In conclusion, the present study provides evidence for the potential application of high doses of gNO as an antimicrobial agent for the treatment of infection in chronic nonhealing ulcers or burn patients, without compromising the viability, and function of skin cells.
Previously, we have shown that gaseous Nitric oxide (gNO) has great potential as an effective topical anti-infective agent for non-healing wounds due to its non-specific antimicrobial properties. ...These same antimicrobial attributes may be useful for pulmonary infections. However, gNO would have limited usefulness as an inhaled antimicrobial agent as continuous exposure to the concentration required for a bactericidal effect (160–200
ppm) leads to methemoglobinemia. To overcome this problem, we investigated whether a thirty minute exposure of 160 ppm every four hours would retain the same antimicrobial effect as continuous delivery.
In vitro, exposure of clinical multi-drug resistant
Staphylococcus aureus and
Escherichia coli strains isolated from the lungs of nosocomial pneumonia patients and a lethal antibiotic-resistant strain of
Pseudomonas aeruginosa, isolated from a deceased cystic fibrosis patient resulted in over a 5 log
10 reduction in bacterial load after multiple thirty minute treatments (4 cycles) every four hours to 160
ppm gNO. The intermittent regimen required 320 (SD
=
0)
ppm
h for 100% lethality whereas the continuous exposure required 800 (SD
=
160)
ppm
h. We have also shown that selection for a gNO resistant phenotype did not lead to decrease sensitivity to gNO therapy (
p
>
0.05). In addition, no host cellular toxicity was observed in human THP-1 monocytes and macrophages following intermittent delivery of a high concentration of gNO, and the proliferation and migration of pulmonary epithelial cells was not adversely affected by the administration of intermittent high-dose gNO. These results justify further studies that should focus on whether intermittent delivery of 160
ppm of gNO every four hours can technically be administered while keeping inhaled NO
2 levels less than 2
ppm and methemoglobin saturation less than 2.5 percent.
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