Effects of Recombinant SARS-CoV-2 Spike Protein Variants on Platelet Morphology and Activation.

Platelets are central elements of hemostasis and also play a pivotal role in the pathogenesis of thrombosis in coronavirus disease 2019. This study was planned to investigate the effects of different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recombinant spike protein variants on platelet morphology and activation. Citrated whole blood collected from ostensibly healthy subjects was challenged with saline (control sample) and with 2 and 20 ng/mL final concentration of SARS-CoV-2 recombinant spike protein of Ancestral, Alpha, Delta, and Omicron variants. Platelet count was found to be decreased with all SARS-CoV-2 recombinant spike protein variants and concentrations tested, achieving the lowest values with 20 ng/mL Delta recombinant spike protein. The mean platelet volume increased in all samples irrespective of SARS-CoV-2 recombinant spike protein variants and concentrations tested, but especially using Delta and Alpha recombinant spike proteins. The values of both platelet function analyzer-200 collagen-adenosine diphosphate and collagen-epinephrine increased in all samples irrespective of SARS-CoV-2 recombinant spike protein variants and concentrations tested, and thus reflecting platelet exhaustion, and displaying again higher increases with Delta and Alpha recombinant spike proteins. Most samples where SARS-CoV-2 recombinant spike proteins were added were flagged as containing platelet clumps. Morphological analysis revealed the presence of a considerable number of activated platelets, platelet clumps, platelet-monocyte, and platelet-neutrophils aggregates, especially in samples spiked with Alpha and Delta recombinant spike proteins at 20 ng/mL. These results provide support to the evidence that SARS-CoV-2 is capable of activating platelets through its spike protein, though such effect varies depending on different spike protein variants.

Spur cells in liver cirrhosis are predictive of acute-on-chronic liver failure and liver-related mortality regardless of severe anaemia.

Chronic anaemia in advanced liver disease is a frequent finding. The aim was to explore the clinical impact of spur cell anaemia, a rare entity typically associated with end-stage of the disease. One-hundred and nineteen patients (73.9% males) with liver cirrhosis of any etiology were included. Patients with bone marrow diseases, nutrients deficiencies and hepatocellular carcinoma were excluded. In all patients, a blood sample was collected to check for the presence of spur cells on blood smear. A complete blood biochemical panel was recorded together with Child-Pugh (CP) score and Model for End-Stage Liver Disease (MELD) score. For each patients, clinically relevant events, such as acute-on-chronic liver failure (ACLF) and 1 year liver-related mortality, were registered. Patients were then grouped according to the percentage of spur cells at smear (> 5%, 1-5%, < 1%). Severe anaemia was defined as haemoglobin levels lower than 8 g/dL. 9.2% of subjects had > 5% spur cells, only 2 had evidence of haemolysis. In patients with > 5% spur cells, haemoglobin and albumin were lower compared with the other sub-group, while MELD score, CP score, International Normalized Ratio, ferritin, creatinine and unconjugated bilirubin were higher. Patients with more spur cells were more decompensated and developed more frequently ACLF. ACLF and liver-related mortality were significantly and independently associated with the presence of > 5% spur cells but not with baseline severe anaemia. Cirrhotic patients have a fairly high prevalence of spur cells, not always associated with severe haemolytic anaemia. The presence of spur red cells is per se associated with a worse prognosis and, therefore, should be always evaluated to prioritize patients for intensive management and eventually liver transplantation.

Chronic anaemia is a frequent finding in liver cirrhosis and spur cell anaemia has been shown to be an uncommon non-immune haemolytic disease typically related to advanced-liver disease. In our study, spur cell anaemia (spur cells >5%) was found in almost 10% of outpatient cirrhotics and was significantly related to more decompensated disease, higher incidence of ACLF and 1 year liver-related mortality. More importantly, the vast majority of patients with high percentage of spur cells did not have severe anaemia. Therefore, spur cells should be searched for in patients with advanced liver disease by a simple blood smear evaluation, even in the absence of significant anaemia, because of relevant prognostic impact and in order to prioritize patients to intensive management and possibly liver transplantation.

Stability of refrigerated whole blood samples for osmotic fragility test

ABSTRACT Background: The osmotic fragility test (OFT), conventionally used for assisting the diagnosis of many erythrocyte disorders, is a manual and time-consuming analysis not daily performed in many medical laboratories. This study was aimed at defining the stability of whole blood samples used for assessing erythrocyte osmotic resistance. Methods: Twenty-one consecutive routine whole blood samples collected into 5.4 mg K2EDTA were tested immediately after collection (day 0) and at different time intervals afterward (day 1, 2, 3, 4, 7, 10 and 14) after storage at 4 °C. The OFT was performed with the Osmored Monotest (1.3% glycerol; Eurospital, Trieste, Italy). Results at the different time points were compared with those obtained at day 0 and with the reference change value (i.e., 33%). Results: The median value of both hyperosmolar and hyposmolar resistance increased from baseline, reaching statistical significance at day 7 for hyperosmolar resistance and at day 1 for hyposmolar resistance, respectively. The median relative increase of hemolysis percentage values become greater than the reference change value at day 3 for hyposmolar resistance, while this limit was never overcome for hyperosmolar resistance. A significant inverse association was found between the mean increase in hyperosmolar resistance and the baseline value of hyperosmolar resistance (r = −0.92), mean corpuscular volume (MCV; r = −0.46) or mean corpuscular hemoglobin (MCH; r = −0.44), as well as between the mean increase in hyposmolar resistance and the baseline value of hyposmolar resistance (r = −0.86), or patient age (r = −0.56). Conclusions: The sample stability seems critical for the OFT. Whole blood specimens should not be stored refrigerated at 4 °C for >2 days before testing.

Assessment of haematopoietic progenitor cell counting with the Sysmex® XN-1000 to guide timing of apheresis of peripheral blood stem cells.

BACKGROUND: Successful peripheral blood stem cell (PBSC) collection depends on optimal timing of apheresis, as usually determined by flow cytometry CD34-positive (+) cell count in peripheral blood (PB). Since this method is costly and labour-intensive, we evaluated the use of the Hematopoietic Progenitor Cell count programme on a Sysmex® XN haematologic analyser (XN-HPC) as a rapid and inexpensive alternative for predicting CD34+ cell count in PB samples. MATERIALS AND METHODS: Haematopoietic progenitor cell and CD34+ cell counts were compared using 273 PB samples collected from 78 healthy donors and 72 patients who underwent PBSC transplantation. We assessed the effectiveness of the XN-HPC in safely predicting pre-harvest CD34+ counts. The most efficient cut-off values of XNHPC were identified. We also evaluated the imprecision (coefficient of variation, CV) and functional sensitivity. RESULTS: Imprecision of the XN-HPC count was <6.3% on daily measurement of three levels of quality control material. Functional sensitivity was 8.9×106/L. A cut-off value of ≥62×106/L XN-HPC for multiple myeloma (MM) patients and ≥30×106/L for all other subjects had both 100% specificity and 100% positive predictive value for identifying samples with CD34+ cells ≥20×106/L. An XN-HPC threshold of <13×106/L identified preharvest CD34+ cell count <10×106/L with 100% sensitivity and 100% negative predictive value. DISCUSSION: The XN-HPC is a fast, easy and inexpensive test that can safely improve apheresis workflow thus possibly replacing other more expensive CD34 counts currently performed and promoting optimal timing of PBSC collection.

CUORE project: implementation of the 10-year risk score.

PURPOSE: The Italian national prevention plan 2005-2008 included 10-year cardiovascular risk (10-CR) assessment of the general population aged 35-69 years using the CUORE project risk score. General practitioners (GPs) were encouraged to collect data on risk factors and 10-CR and to contribute to the Cardiovascular Risk Observatory (CRO). The aim is to demonstrate feasibility and effectiveness of 10-CR assessment as a first step to implement primary preventive actions at the individual level. METHODS: Data were collected using CUORE.EXE software, easily and freely downloadable by GPs from the CUORE project website (www.cuore.iss.it). CRO provides a web platform to analyse and compare data on 10-CR and risk factors at regional and national levels with the aim of supporting health policy decision processes. RESULTS: From January 2007 to May 2010, 2,858 GPs downloaded cuore.exe; 139,269 CR assessments on 117,345 persons were sent to CRO. CR mean was 3.0% in women, 8.3% in men; 30% of men and 65% of women were at lower risk (CR < 3%), 9.2% of men and 0.4% of women were at high risk (CR ≥ 20%). Among those with at least two risk assessments (n = 5,948), 8% (95% CI 7-9%) shifted to a lower risk class after 1 year. Systolic blood pressure mean levels decreased by 1.6 mmHg (95% CI 1.2-2.1 mmHg), diastolic blood pressure by 0.9 mmHg (95% CI 0.5-1.3 mmHg), total cholesterol by 5.6 mg/dl (95% CI 4.3-6.8 mg/dl), and smokers prevalence by 3.5% (95% CI 2.5-4.6%); high-density lipoprotein cholesterol increased in women by 1 mg/dl (95% CI 0.5-1.4 mg/dl). CONCLUSIONS: Data demonstrate that 10-CR assessment can be the first step to implement preventive actions in primary care.

[Cardiovascular Risk Assessment: preliminary results]. / Osservatorio del Rischio Cardiovascolare: primi risultati.

BACKGROUND: The Italian National Prevention plan includes 10-year cardiovascular risk (CR) assessment of the Italian general population aged 35-69 years using the CUORE Project risk score. A national training program for general practitioners (GPs) was launched by the Ministry of Health in 2003. GPs were encouraged to collect data on risk factors and risk assessment and to contribute to the CUORE Project Cardiovascular Risk Observatory (CRO). The aim of this analysis is to demonstrate the feasibility and effectiveness of risk assessment in primary care. METHODS: The cuore.exe software, free of charge for GPs and easily downloadable from the CUORE Project web site (www.cuore.iss.it), is the frame for the GP data collection. The CRO provides a platform to analyze data collected on risk assessment and risk factors, and compare results at regional and national level in order to support health policy makers in their decision process. RESULTS: From January 2007 to April 2009, 2858 GPs have downloaded the cuore.exe software; 102,113 risk assessments were sent to the CRO based on risk factors profile of 87,556 persons (3617 persons had more than 1 risk assessment). Mean level of CR was 3.1% in women and 8.4% in men; 30% of men and 65% of women were at low risk (CR < 3%), 9% of men and 0.4% of women were found at high risk (CR > or = 20%). Among those with at least 2 risk assessments, 8% shifted to a lower class of risk after 1 year. Mean level of systolic and diastolic blood pressure decreased by about 1% in 1 year; total cholesterol more than 2%, and prevalence of smokers decreased by about 3% in the second risk assessment. CONCLUSIONS: These data demonstrate that risk assessment can be included as a first step of prevention in primary care. The CUORE Project individual score is expected to become an important tool for GPs to assess their patients' CR, to promote primary prevention, and to focus attention to healthy lifestyle adoption.

Italian network for obesity and cardiovascular disease surveillance: a pilot project.

BACKGROUND: Also in Mediterranean countries, which are considered a low risk population for cardiovascular disease (CVD), the increase in body mass index (BMI) has become a public health priority. To evaluate the feasibility of a CVD and obesity surveillance network, forty General Practitioners (GPs) were engaged to perform a screening to assess obesity, cardiovascular risk, lifestyle habits and medication use. METHODS: A total of 1,046 women and 1,044 men aged 35-74 years were randomly selected from GPs' lists stratifying by age decade and gender. Anthropometric and blood pressure measurements were performed by GPs using standardized methodologies. BMI was computed and categorized in normal weight (BMI 18.5-24.9 kg/m2), overweight (BMI 25.0-29.9 kg/m2) and obese (BMI > or = 30 kg/m2). Food frequency (per day: fruits and vegetables; per week: meat, cheese, fish, pulses, chocolate, fried food, sweet, wholemeal food, rotisserie food and sugar drink) and physical activity (at work and during leisure time) were investigated through a questionnaire. CVD risk was assessed using the Italian CUORE Project risk function. RESULTS: The percentage of missing values was very low. Prevalence of overweight was 34% in women and 50% in men; prevalence of obesity was 23% in both men and women. Level of physical activity was mostly low or very low. BMI was inversely associated with consumption of pulses, rotisserie food, chocolate, sweets and physical activity during leisure time and directly associated with consumption of meat. Mean value of total cardiovascular risk was 4% in women and 11% in men. One percent of women and 16% of men were at high cardiovascular risk (> or = 20% in 10 years). Normal weight persons were four times more likely to be at low risk than obese persons. CONCLUSION: This study demonstrated the feasibility of a surveillance network of GPs in Italy focusing on obesity and other CVD risk factors. It also provided information on lifestyle habits, such as diet and physical activity.

[Occupational and leisure time physical activity: trend in the Italian population]. / Attività fisica lavorativa e nel tempo libero: come si e modificata nella popolazione italiana?

BACKGROUND: Over the last decades a change in physical activity habits of the Italian population has been observed. The aim of this study was to compare occupational and leisure-time physical activity, to assess the relationship between physical activity and cardiovascular risk factors and the variation in cardiovascular risk profile measured 20 years apart in the Italian population. METHODS: In two populations aged 35-69 years (MATISS 1984-1987: 2041 men, 2424 women; OEC 1998-2002: 4214 men, 4206 women) gender-specific levels of occupational (occupational physical activity [OPA]-light, OPA-moderate, OPA-heavy) and leisure-time (leisure-time physical activity [LTPA]-low, LTPA-moderate, LTPA-high) physical activity were compared. Relationship between physical activity and cardiovascular risk factors was evaluated in the two samples using logistic regression models adjusted for age, heart rate, educational level and other possible confounding variables in men and women separately. The 10-year cardiovascular risk was assessed in the two periods and in different physical activity strata using the Progetto CUORE risk score. RESULTS: Comparing the two studies, prevalence of OPA-low had decreased, whereas the prevalence of LTPA-low had increased. With increasing LTPA blood pressure, heart rate and glycemia decreased, whereas high-density lipoprotein-cholesterol increased with a positive effect on obesity, smoking habit and cardiovascular risk. CONCLUSIONS: Over the last 20 years, physical activity apparently changed: currently men and women dedicate more time to physical activity during leisure-time, and are less active at work. More active people have lower levels of major cardiovascular risk factors. Societal efforts are needed to increase physical activity levels in the population.

[Distribution of the global cardiovascular risk in the Italian population: results from the cardiovascular epidemiologic observatory]. / Distribuzione del rischio cardiovascolare globale nella popolazione italiana: risultati dell'Osservatorio Epidemiologico Cardiovascolare.

BACKGROUND: The aim of this study was to assess the 10-year cardiovascular risk categories using risk chart, recently set up by the National Institute of Health in the population examined by the Cardiovascular Epidemiologic Observatory. METHODS: 3745 men and 3664 women aged 40-69 years were classified into five risk categories (< 5 %; 5-10%; 10-15%; 15-20%; > or = 20%) taking into account age, smoking habit, history of diabetes, systolic blood pressure, serum cholesterol and excluding those already under treatment for hypertension and hypercholesterolaemia or experienced a previous major cardiovascular event (1937 persons: 955 men, 982 women). RESULTS: Proportion of people estimated at risk in 10 years > or = 20% is minimal in the youngest age range, increases in adulthood, duplicates in smokers and is higher in diabetics. In non-diabetic men that proportion varies between 3.4% in non-smokers and 5.6% in smokers. All women at risk are already under specific treatment. CONCLUSIONS: Cardiovascular Epidemiologic Observatory data allowed to assess the expected proportion of individuals at risk in 10 years > or = 20%. Besides attention to high-risk individuals, preventive measures supporting a healthier lifestyle in the general population must be adopted, considering that it will produce the greatest number of events.