Mechanical behaviour and rupture of normal and pathological human ascending aortic wall

The mechanical properties of aortic wall, both healthy and pathological, are needed in order to develop and improve diagnostic and interventional criteria, and for the development of mechanical models to assess arterial integrity. This study focuses on the mechanical behaviour and rupture conditions of the human ascending aorta and its relationship with age and pathologies. Fresh ascending aortic specimens harvested from 23 healthy donors, 12 patients with bicuspid aortic valve (BAV) and 14 with aneurysm were tensile-tested in vitro under physiological conditions. Tensile strength, stretch at failure and elbow stress were measured. The obtained results showed that age causes a major reduction in the mechanical parameters of healthy ascending aortic tissue, and that no significant differences are found between the mechanical strength of aneurysmal or BAV aortic specimens and the corresponding age-matched control group. The physiological level of the stress in the circumferential direction was also computed to assess the physiological operation range of healthy and diseased ascending aortas. The mean physiological wall stress acting on pathologic aortas was found to be far from rupture, with factors of safety (defined as the ratio of tensile strength to the mean wall stress) larger than six. In contrast, the physiological operation of pathologic vessels lays in the stiff part of the response curve, losing part of its function of damping the pressure waves from the heart

Gene Expression Signature in Peripheral Blood Detects Thoracic Aortic Aneurysm

BACKGROUND: Thoracic aortic aneurysm (TAA) is usually asymptomatic and associated with high mortality. Adverse clinical outcome of TAA is preventable by elective surgical repair; however, identifying at-risk individuals is difficult. We hypothesized that gene expression patterns in peripheral blood cells may correlate with TAA disease status. Our goal was to identify a distinct gene expression signature in peripheral blood that may identify individuals at risk for TAA. METHODS AND FINDINGS: Whole genome gene expression profiles from 94 peripheral blood samples (collected from 58 individuals with TAA and 36 controls) were analyzed. Significance Analysis of Microarray (SAM) identified potential signature genes characterizing TAA vs. normal, ascending vs. descending TAA, and sporadic vs. familial TAA. Using a training set containing 36 TAA patients and 25 controls, a 41-gene classification model was constructed for detecting TAA status and an overall accuracy of 78+/-6% was achieved. Testing this classifier on an independent validation set containing 22 TAA samples and 11 controls yielded an overall classification accuracy of 78%. These 41 classifier genes were further validated by TaqMan real-time PCR assays. Classification based on the TaqMan data replicated the microarray results and achieved 80% classification accuracy on the testing set. CONCLUSIONS: This study identified informative gene expression signatures in peripheral blood cells that can characterize TAA status and subtypes of TAA. Moreover, a 41-gene classifier based on expression signature can identify TAA patients with high accuracy. The transcriptional programs in peripheral blood leading to the identification of these markers also provide insights into the mechanism of development of aortic aneurysms and highlight potential targets for therapeutic intervention. The classifier genes identified in this study, and validated by TaqMan real-time PCR, define a set of promising potential diagnostic markers, setting the stage for a blood-based gene expression test to facilitate early detection of TAA

CORRELATION BETWEEN IMMUNOHISTOCHEMICAL EXPRESSION OF PROLIFERATING CELL NUCLEAR ANTIGEN AND FLOW-CYTOMETRY PARAMETERS IN COLORECTAL NEOPLASIA

PURPOSE: Proliferating cell nuclear antigen immunohistochemical expression and flow cytometry techniques were used in this study to estimate the proliferation tendency and biologic aggressiveness in benign and malignant epithelial tumors of the colon and rectum. METHODS: Thirty-five adenomas and GO adenocarcinomas were studied immunohistochemically concerning proliferating cell nuclear antigen positivity in tumor cell nuclei. In addition, flow cytometry techniques were used to estimate the DNA content and percentage of tumor cells in the S-phase. RESULTS: The mean proliferating cell nuclear antigen score for adenomas was 38 percent compared with a mean score of 50.4 percent for adenocarcinomas that were studied (P < 0.05). In dysplastic areas of malignantly transformed adenomas (n = 5), the highest proliferating cell nuclear antigen score (80 percent) was focally observed. Taking flow cytometry parameters into account, we found out that proliferating cell nuclear antigen can be used as an indirect indicator of the number of cells in the S-phase (SPE) but not as an independent prognostic factor. Statistical significance was found between Type III (aneuploid carcinomas) and increased proliferating cell nuclear antigen expression (proliferating cell nuclear antigen score greater than or equal to 60 percent). Furthermore, aneuploidy was especially found on cancer located on the left colon (44 percent vs. 14 percent of right colon neoplasms). Considering DNA ploidy of the above neoplasms, the aneuploid adenocarcinomas had a tendency for poorer prognosis especially if they were related to Dukes Stage C female patients. CONCLUSIONS: The comparative assessment of the above parameters might be of considerable importance in the study of the proliferation activity of any form of colorectal neoplasia

A meta-analysis of randomized trials comparing bovine pericardium and other patch materials for carotid endarterectomy

Objective: Patch angioplasty during carotid endarterectomy is commonly used to treat symptomatic and asymptomatic carotid artery stenosis. The objective of the present study was to compare the different patch materials that are currently available (synthetic vs venous vs bovine pericardium) in terms of short- and long-term outcomes. Methods: This study was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and eligible randomized control trials were identified through a comprehensive search of PubMed, Scopus, and Cochrane Central published until September 2017. A meta-analysis was conducted with the use of a random effects model. The I2 statistic was used to assess for heterogeneity. The primary study end point was the incidence of long-term restenosis. Secondary study end points were 30-day stroke, transient ischemic attack (TIA), myocardial infarction, neck wound infection, local hematoma, carotid artery thrombosis, cranial nerve injury, long-term stroke incidence, and death. Results: Eighteen studies and 3234 patients were included. The risk of 30-day stroke (relative risk [RR], 1.00; 95% confidence interval [CI], 0.45-2.19; I2 = 0%), TIA (RR, 1.14; 95% CI, 0.41-3.19; I2 = 0%), myocardial infarction (odds ratio, 0.75; 95% CI, 0.14-3.97; I2 = 0%), death (RR, 0.53; 95% CI, 0.21-1.34; I2 = 0%), wound infection (RR, 1.84; 95% CI, 0.43-7.81; I2 = 0%), carotid artery thrombosis (RR, 1.47; 95% CI, 0.44-4.97; I2 = 0%), cranial nerve palsy (RR, 1.21; 95% CI, 0.53-2.77; I2 = 0%), and long-term stroke (RR, 2.33; 95% CI, 0.76-7.10; I2 = 0%), death (RR, 1.09; 95% CI, 0.65-1.83; I2 = 0%) and restenosis of greater than 50% (RR, 0.48; 95% CI, 0.19-1.20; I2 = 0%) were similar between the synthetic vs venous patch groups. Also, no differences in terms of 30-day stroke (RR, 0.31; 95% CI, 0.02-5.16; I2 = 63.1%), TIA (RR, 0.49; 95% CI, 0.14-1.76; I2 = 0%), death (RR, 0.74; 95% CI, 0.05-10.51; I2 = 31.7%), carotid artery thrombosis (RR, 0.13; 95% CI, 0.02-1.07; I2 = 0%), and long-term restenosis of greater than 70% (RR, 0.15; 95% CI, 0.01-2.29; I2 = 70.9%) were detected between the synthetic polytetrafluoroethylene and Dacron patch groups. The comparison between the bovine pericardium vs synthetic patch did not yield any statistically significant results in terms of 30-day stroke (RR, 1.44; 95% CI, 0.19-10.79; I2 = 12.7%), TIA (RR, 1.05; 95% CI, 0.11-10.27; I2 = 0%), local neck hematoma (RR, 4.01; 95% CI, 0.46-34.85; I2 = 0%), and death (RR, 4.01; 95% CI, 0.46-34.85; I2 = 0%). Conclusions: Closure of the carotid arteriotomy with any of the studied patch materials seems to be similar in terms of short- and long-term end points. However, additional randomized trials with adequate follow-up periods are needed to compare bovine pericardium patches with other patch materials. © 2018 Society for Vascular Surger

Do the Kinetics of Antibody Responses Predict Clinical Outcome in Hospitalized Patients With Moderate-to-Severe COVID-19?

Background/Aim: The relationship between the kinetics of antibody responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the severity of Coronavirus Disease 2019 (COVID-19) is poorly understood. The aim of the present study was to investigate whether serum SARS-CoV-2 antibody kinetics serve as an early predictor of clinical deterioration or recovery in hospitalized patients with COVID-19. Patients and Methods: In this prospective observational study, 102 consecutive patients (median age: 60 years, 58% males) with symptomatic COVID-19 infection diagnosed by real-time polymerase chain reaction assay, hospitalized in two tertiary hospitals, were included. Rapid test for qualitative detection of immunoglobulin M (IgM) and immunoglobulin G (IgG) SARS-CoV-2 antibodies was performed at pre-defined time intervals during hospitalization (days: 0, 3, 7, 10, 14, 21 and 28). Results: During a 3-month follow-up period after COVID-19 disease onset, a total of 87 patients were discharged, 12 patients were intubated and entered the Intensive Care Unit, and three patients died. The median time for seroconversion was 10 days for IgM and 12 days for IgG post onset of symptoms. Univariate logistic regression analysis found no associations between IgM or IgG positivity and clinical outcomes or complications during hospitalization for COVID-19 infection. Diabetes and dyslipidemia were the only clinical risk factors predictive of COVID-19-related complications during hospitalization. Conclusion: SARS-CoV-2 antibody responses do not predict clinical outcome in hospitalized patients with moderate-to-severe COVID-19 infection. © 2022 International Institute of Anticancer Research. All rights reserved