Evaluation of extraction-free RT-qPCR methods for SARS-CoV-2 diagnostics

Extraction-based real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) is currently the “gold standard” in SARS-CoV-2 diagnostics. However, some extraction-free RT-qPCR techniques have recently been developed. In this study, we compared the sensitivity of traditional extraction-based, heated extraction-free, and unheated extraction-free RT-qPCR methods for SARS-CoV-2 detection in nasopharyngeal swabs from symptomatic individuals. The unheated extraction-free method showed perfect agreement with the standard extraction-based RT-qPCR. By contrast, the heat-treated technique was associated with an 8.2% false negativity rate. Unheated extraction-free RT-qPCR for the molecular diagnosis of SARS-CoV-2 is a valuable alternative to the traditional extraction-based methods and may accelerate turnaround times by about two hours

Towards a Digital Twin of Coronary Stenting: A Suitable and Validated Image-Based Approach for Mimicking Patient-Specific Coronary Arteries

Considering the field of application involving stent deployment simulations, the exploitation of a digital twin of coronary stenting that can reliably mimic the patient-specific clinical reality could lead to improvements in individual treatments. A starting step to pursue this goal is the development of simple, but at the same time, robust and effective computational methods to obtain a good compromise between the accuracy of the description of physical phenomena and computational costs. Specifically, this work proposes an approach for the development of a patient-specific artery model to be used in stenting simulations. The finite element model was generated through a 3D reconstruction based on the clinical imaging (coronary Optical Coherence Tomography (OCT) and angiography) acquired on the pre-treatment patient. From a mechanical point of view, the coronary wall was described with a suitable phenomenological model, which is consistent with more complex constitutive approaches and accounts for the in vivo pressurization and axial pre-stretch. The effectiveness of this artery modeling method was tested by reproducing in silico the stenting procedures of two clinical cases and comparing the computational results with the in vivo lumen area of the stented vessel

Comparative diagnostic performance of rapid antigen detection tests for COVID-19 in a hospital setting

Background: The availability of accurate and rapid diagnostic tools for COVID-19 is essential for tackling the ongoing pandemic. Our study aimed to quantify the performance of available antigen-detecting rapid diagnostic tests (Ag-RDTs) in a real-world hospital setting. Methods: In this retrospective analysis, the diagnostic performance of 7 Ag-RDTs was compared with real-time reverse transcription quantitative polymerase chain reaction assay in terms of sensitivity, specificity and expected predictive values. Results: A total of 321 matched Ag-RDTreal-time reverse transcription quantitative polymerase chain reaction samples were analyzed retrospectively. The overall sensitivity and specificity of the Ag-RDTs was 78.7% and 100%, respectively. However, a wide range of sensitivity estimates by brand (66.0%–93.8%) and cycle threshold (Ct) cut-off values (Ct <25: 96.2%; Ct 30–35: 31.1%) was observed. The optimal Ct cut-off value that maximized sensitivity was 29. Conclusions: The routine use of Ag-RDTs may be convenient in moderate-to-high intensity settings when high volumes of specimens are tested every day. However, the diagnostic performance of the commercially available tests may differ substantially

Regional analysis with quantitative computed tomography after lung transplantation

Regional analysis with quantitative computed tomography (CT) of graft could be an attractive technique to interpret lung patterns after transplantation. Aim of this study was the definition of lung regional patterns in the early post-transplantation period. We prospectively collected the CT scans at end-expiration (EXP) and full-inspiration (INSP) of patients at 3 months after lung transplantation (LT). Lungs were segmented from both scans. INSP images were registered to EXP by optical flow to obtain maps of density variation (\u394HU) with pixel-by-pixel subtraction. We evaluated a classification of the pixels from maps of \u394HU in low ventilation (LV), consolidation (C), air trapping (AT) and healthy parenchyma (H). Patients who experienced uneventful early postoperative course after bilateral LT were enrolled. The figure shows the resulted composition of the parenchyma in 20 patients: LV=59.6\ub15.4%, C=1.7\ub10.4%, AT=0.06\ub10.05%, H=38.7\ub15.6%. To note that low ventilation pattern still affected the majority of lung tissue while consolidation and air trapping were negligible. Quantitative CT regional analysis may provide a significant advance in the interpretation of ventilation abnormalities after LT

Reliability of computed tomography (CT) quantitative analysis in lung transplantation follow-up

Functional analysis of CT imaging in lung-transplanted patients is an emerging tool for the interpretation of parenchymal (patterns) evolution after lung transplantation (LT). Aim of this study was to determine the trends of pulmonary function (PFT) indices and quantitative CT parameters within 1-year followup. We prospectively collected PFT parameters (FEV1, FVC) and inspiration/expiration CT scans of LT patients at standard time-points (3-6-12 months). Specific gas volume (SV , ml/g) was measured on CT images as previously described (Salito et al, Radiology 2009; Aliverti et al, ERJ 2013). Selected quantitative indexes were lung volume at inspiration (V ) and the difference between inspiration and expiration SV normalized on expiration SV : \u394SV /SV EXP. Patients who experienced uneventful 12 months postoperative course after bilateral LT were included. Fifteen patients completed the trial. As expected, FEV1 and FVC values significantly improved at each time-point until the 12-month check. Correspondingly, V and \u394SV / SV EXP increased in the same fashion with a trend toward healthy values (Fig1, bottom panels). This preliminary trial evidenced the reliability of specific gas volume analysis as an attractive quantitative CT parameter of lung function after LT. Future studies are requested to verify the accuracy of specific gas volume analysis in the evaluation of patients with lung allograft dysfunction

The effect of primary graft dysfunction after lung transplantation on parenchymal remodeling detected by quantitative computed tomography

Background: Regional analysis by computed tomography (CT) is an attractive technique to interpret lung patterns after transplantation (LTx). We evaluated the application of CT functional mask derived parameters to determine whether development of primary graft dysfunction (PGD) is associated with short and/or long-term postoperative evidences of pulmonary function alterations. Methods: A total of 38 patients who underwent bilateral LTx were evaluated at 24, 48 and 72 hours after the end of surgery to establish PGD occurrence and grading. CT scans at 3 and 12 months after LTx were analyzed to measure specific gas volume (SV g ) changes normalized on expiratory SVgEXP of the whole lung (\u394SV g /SV gEXP ) and to obtain functional masks of density variation, namely maps of low ventilation (LV), consolidation (C), air trapping (AT) and healthy parenchyma (H). Results: Our main result was the evidence of a marked decrease in \u394SV g /SV gEXP in all subjects, irrespectively on PGD, at each time point after LTx, indicating a high degree of ventilation defects versus healthy. High percentages of LV were found in all subjects while percentages of AT and C were negligible. Conclusions: We demonstrate that quantification of ventilation defects by CT functional mask offers insights into the correlation between PGD and pulmonary function after LTx at short and mid-term

Anti-tumor activity of selective inhibitors of XPO1/CRM1-mediated nuclear export in diffuse malignant peritoneal mesothelioma : the role of survivin

Survivin, which is highly expressed and promotes cell survival in diffuse malignant peritoneal mesothelioma (DMPM), exclusively relies on exportin 1 (XPO1/ CRM1) to be shuttled into the cytoplasm and perform its anti-apoptotic function. Here, we explored the efficacy of Selective Inhibitors of Nuclear Export (SINE), KPT-251, KPT-276 and the orally available, clinical stage KPT-330 (selinexor), in DMPM preclinical models. Exposure to SINE induced dose-dependent inhibition of cell growth, cell cycle arrest at G1-phase and caspase-dependent apoptosis, which were consequent to a decrease of XPO1/CRM1 protein levels and the concomitant nuclear accumulation of its cargo proteins p53 and CDKN1a. Cell exposure to SINE led to a time-dependent reduction of cytoplasmic survivin levels. In addition, after an initial accumulation, the nuclear protein abundance progressively decreased, as a consequence of an enhanced ubiquitination and proteasome-dependent degradation. SINE and the survivin inhibitor YM155 synergistically cooperated in reducing DMPM cell proliferation. Most importantly, orally administered SINE caused a significant antitumor effect in subcutaneous and orthotopic DMPM xenografts without appreciable toxicity. Overall, we have demonstrated a marked efficacy of SINE in DMPM preclinical models that may relay on the interference with survivin intracellular distribution and function. Our study suggests SINE-mediated XPO1/ CRM1 inhibition as a novel therapeutic option for DMPM

Evaluation of mediators associated with the inflammatory response in prostate cancer patients undergoing radiotherapy

A recent "hot topic" in prostate cancer radiotherapy is the observed association between acute/late rectal toxicity and the presence of abdominal surgery before radiotherapy. The exact mechanism is unclear. Our working hypothesis was that a previous surgery may influence plasma level of inflammatory molecules and this might result in enhanced radiosensitivity. We here present results on the feasibility of monitoring the expression of inflammatory molecules during radiotherapy. Plasma levels of a panel of soluble mediators associated with the inflammatory response were measured in prostate cancer patients undergoing radical radiotherapy. We measured 3 cytokines (IL-1b, IL-6, and TNF alpha), 2 chemokines (CCL2 and CXCL8), and the long pentraxin PTX3. 20 patients were enrolled in this feasibility evaluation. All patients were treated with IMRT at 78 Gy. 3/20 patients reported grade 2 acute rectal toxicity, while 4/20 were scored as grade 2 late toxicity. CCL2 was the most interesting marker showing significant increase during and after radiotherapy. CCL2 levels at radiotherapy end could be modelled using linear regression including basal CCL2, age, surgery, hypertension, and use of anticoagulants. The 4 patients with late toxicity had CCL2 values at radiotherapy end above the median value. This trial is registered with ISRCTN64979094

Survivin expression in ovarian cancer and its correlation with clinico-pathological, surgical and apoptosis-related parameters

We investigated the association of survivin expression with prognosis and other apoptosis-related biological factors in 110 primary ovarian cancer patients admitted to the Division of Gynecologic Oncology, Catholic University of Rome. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections by using polyclonal antibody ab469 for survivin, and mouse monoclonal antibodies (clone 124 and DO-7), for bcl-2 and p53, respectively. Cytoplasmic survivin immunoreaction was observed in 84.5% cases, while nuclear survivin immunostaining was observed in 29.1% cases. We failed to find any relationship between cytoplasmic survivin positivity rate and any of the parameters examined. Serous tumours showed a lower percentage of nuclear survivin positivity with respect to other histotypes (20.5 vs 48.6%, respectively; P-value=0.004). The percentage of nuclear survivin positivity was higher in cases subjected to primary tumour cytoreduction (43.5%), with respect to patients subjected to exploratory laparotomy (20%) (P=0.024). Bcl-2 and p53 were, respectively, expressed in 27.3 and 60.0% of the cases and their expression was not correlated with survivin status. During the follow-up period, progression and death of disease were observed in 68 (61.8%) and 53 (48.2%) cases, respectively. There was no difference in time to progression and overall survival according to survivin status in ovarian cancer patients. In conclusion, in our experience, the immunohistochemical assessment of survivin status does not seem to be helpful in the prognostic characterisation of ovarian cancer. A more in depth investigation of the complex physiology of divergent survivin variants is needed in order to clarify the biological and the clinical role of differentially located survivin isoforms