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Type 2 diabetes mellitus (T2DM) remains an important public health problem in both developing and developed countries. In addition, the recent COVID-19 pandemic has revealed furthel risks for diabetes patients in terms of symptoms and disease progression. Higher mortality and morbidity are related to the complexity of the pathology of this chronic underlying disease, which negatively affects the immune response to the SARSCoV-2 virus. The humoral response plays an important role in the eradication of the virus; thus, it was analyzed in vaccinated diabetics who underwent COVID-19, as well as in the control group. The aim of this study was to assess the prevalence and level of IgG antibodies raised against the nucleocapsid protein (NCP), S1 subunit receptor binding domain (RBD) and subunit Spike 2 (S2) subunit of the virus’s S protein using the Microblot Array test. The results demonstrated significantly lower prevalence and titers of anti-SARS antibodies in diabetic patients compared to the control group. In addition, antibody titers were negatively related to the duration of this chronic disease, body mass index (BMI), comorbidities and HbA1c concentration. Further research is needed to develop the best strategy for specific prevention of SARS-CoV-2 infection in diabetic patients.

The modified surface layers of Mg enriched with Al and Si were fabricated by thermochemical treatment. The substrate material in contact with an Al + 20 wt.% Si powder mixture was heated to 445°C for 40 or 60 min. The microstructure of the layers was examined by OM and SEM. The chemical composition of the layer and the distribution of elements were determined by energy dispersive X-ray spectroscopy (EDS). The experimental results show that the thickness of the layer is dependent on the heating time. A much thicker layer (1 mm) was obtained when the heating time was 60 min than when it was 40 min (600 μm). Both layers had a non-homogeneous structure. In the area closest to the Mg substrate, a thin zone of a solid solution of Al in Mg was detected. It was followed by a eutectic with Mg17Al12 and a solid solution of Al in Mg. The next zone was a eutectic with agglomerates of Mg2Si phase particles; this three-phase structure was the thickest. Finally, the area closest to the surface was characterized by dendrites of the Mg17Al12 phase. The microhardness of the modified layer increased to 121-236 HV as compared with 33-35 HV reported for the Mg substrate.

We identified the beetle fauna of springs of a small lowland river and attempted to determine the direction and magnitude of beetle migration between the springs and neighboring water bodies in the river valley, as well as the local environmental factors and landscape parameters that most influence the character of aquatic beetle assemblages in the springs. We studied springs of three limnological types, along the entire length of the river valley, and identified 42 beetle species. All types of springs were dominated by stagnobiontic species, which enter springs from other aquatic environments, mainly via dispersion by air. We also found a small proportion of crenophiles and a substantial proportion of rheophiles and tyrphophiles, which was linked to the close proximity of the river and dystrophic water bodies. The fauna of the springs was affected to a similar degree by local environmental factors and by landscape factors acting on a broader scale. This indicates the need for broader consideration of landscape factors, which are often neglected in ecological studies.

The influence of dredging on the dragonfly assemblages of the small regulated lowland River Krąpiel (north-western Poland) was analyzed a short time after the dredging. Dragonfly assemblages were destroyed, but they began to recover rapidly. Many biocoenotic indices reached high values at just six months after the dredging. The recolonization first occurred as a result of larval drift, and then, via dispersion of adult dragonflies. This process took place in conditions different from the prevailing conditions in the period before dredging, in terms of microhabitat availability and physico-chemical conditions. Compared to the previous assemblage, the emerging assemblage was more typical of assemblages found in small, natural running waters. Therefore, dredging (carried out for economic reasons) could be regarded as a process that unintentionally had a positive influence on odonate assemblages. Currently, when most small watercourses are regulated, dredging that is properly planned and controlled has proven to protect the natural fauna. It is worthwhile to apply lessons learned from examples of active fauna protection to what is currently known as “the rotational model” for dredging.

The goal of the study was to identify the beetle fauna of a small lowland river valley against its spatial arrangement and the directions of beetle migrations between habitats, as well as to determine which environmental factors affect the characteristics of water beetle populations in a river valley's lentic water bodies. The field studies were carried out in various types of water bodies. 112 species of beetles with various ecological characteristics were identified. It was demonstrated that the diversity of water bodies in the valley is conducive to high local species richness. At the same time, the observed high degree of faunistic individualism may be regarded as a sign of poor symmetry in the directions of fauna propagation, particularly that of stagnobionts. The authors argue that high individualism is the consequence of poor hydrological contact between the water bodies due to topography and rare instances of high tide in the river, which, in turn, is the reason for active overflights remaining the main mean of migration between those water bodies. The factors restricting migration of fauna between the water bodies include certain landscape characteristics of the catchment which form topographical obstacles, mainly numerous and dense forest areas. The character of fauna in the respective types of water bodies is affected also by internal environmental factors, particularly the degree to which they are overgrown with macrophytes, type of bottom, type of mineral and organic matter as well as physical parameters of water, such as saturation, pH, temperature and biological oxygen demand.

In this paper we introduce a semi-analytic algorithm for 3-dimensional image reconstruction for positron emission tomography (PET). The method consists of the back-projection of the acquired data into the most likely image voxel according to time-of-flight (TOF) information, followed by the filtering step in the image space using an iterative optimization algorithm with a total variation (TV) regularization. TV regularization in image space is more computationally efficient than usual iterative optimization methods for PET reconstruction with full system matrix that use TV regularization. The efficiency comes from the one-time TOF back-projection step that might also be described as a reformatting of the acquired data. An important aspect of our work concerns the evaluation of the filter operator of the linear transform mapping an original radioactive tracer distribution into the TOF back-projected image. We obtain concise, closed-form analytical formula for the filter operator. The proposed method is validated with the Monte Carlo simulations of the NEMA IEC phantom using a one-layer, 50 cm-long cylindrical device called Jagiellonian PET scanner. The results show a better image quality compared with the reference TOF maximum likelihood expectation maximization algorithm., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Background: Glycemic memory of endothelial cells is an effect of long-lasting hyperglycemia and is a cause of various diabetics complications, that arises despite of the treatment targeted towards returning low glucose level in blood system. On the other hand, endothelial dysfunction, which is believed to be a main cause of cardiovascular complications, is exhibited in the changes of mechanical properties of cells. Although formation of the glycemic memory was widely investigated, its impact on the mechanical properties of endothelial cells has not been studied yet., Methods: In this study, nanoindentaion with a tip of an atomic force microscope was used to probe the long-term changes (through 26 passages, c.a. 80 days) in mechanical properties of EA.hy926 endothelial cells cultured in hyperglycemic conditions. As a complementary method, alterations in the structure of actin cytoskeleton were visualized by fluorescent staining of F-actin., Results: We observed a gradual stiffening of the cells up to 20th passage for cells cultured in high glucose (25 mM). Fluorescence imaging has revealed that this behavior resulted from systematic remodeling of the actin cytoskeleton. In further passages, a drop in stiffness had occurred. The most interesting finding was recorded for cells transferred after 14 passages from high glucose to normal glucose conditions (5mM). After the transfer, the initial drop in stiffness was followed by a return of the cell stiffness to the value previously observed for cells cultured constantly in high glucose, Conclusions: Our results indicate that glycemic memory causes irreversible changes in stiffness of endothelial cells. The formation of the observed "stiffness memory" could be important in the context of vascular complications which develop despite the normalization of the glucose level.

The paper is an introduction to the issue of endothelial microparticles, their biology and function. The historical view of microparticle research and actual knowledge about microaprticle formation, structure and molecular composition are presented. The new directions of endothelial microparticle research are discussed with the emphasis of their coagulation aspects.

Disruption of the intercellular interactions between endothelial cells leads to endothelial dysfunction. The role of nanoparticles in plasma membrane stability, actin cytoskeleton organization and intercellular junctions is unclear. Human umbilical vein endothelial cells were treated with zinc oxide NPs in vitro. Cell shape, adhesiveness and plasma membrane integrity were analyzed by means of optical fluorescence microscopy, scanning electron microscopy and flow cytometry methods. Additionally, lactate dehydrogenase activity assay and annexin V staining were performed. The scanning electron microscopy analysis showed changes in morphology and surface topography. The F-actin organization was typical for migrating cells. Cell membrane damage (significant increase in lactate dehydrogenase release and annexin V staining) was observed in the concentration of ZnO nanoparticles above 30 microg/ml. The relationship between ZnO nanoparticles and endothelial dysfunction was clearly established and the importance of cytoskeleton reorganization and loosening of the continuous endothelial monolayer after nanoparticles exposure has been documented.

A 27-year-old male with a six-year history of hypereosinophilic syndrome (HES) presented with a native mitral valve thrombus, despite therapeutic oral anticoagulation. The thrombus was removed, the mitral valve replaced, and subsequent oral anticoagulation maintained at a higher level (INR 3.5). The patient developed two recurrences of mitral valve thrombosis requiring urgent reoperations, and died shortly after the second intervention. A scanning electron microscopy analysis of the native mitral valve thrombus removed during the first cardiac surgery revealed tightly packed thin fibrin strands forming fuzzy irregular structures, with areas of an almost solid fibrin clot. The fibrin networks indicated a heightened thrombin generation, and may account for a diminished susceptibility to intrinsic fibrinolysis. In conclusion, the unfavorably altered compact structure of the fibrin-rich thrombus, which formed despite adequate anticoagulation, might in part explain the recurrent valvular thrombosis. It may also represent a novel prothrombotic mechanism that operates in HES.

Little is known about architecture of intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA). We present a 74-year-old woman with AAA and high cardiovascular risk. Scanning electron microscopy of ILT removed during surgery showed that its luminal layer is relatively rich in fibrin fibers forming irregular compact structure with low amounts of erythrocytes and platelets, while abluminal portion is composed of densely packed fibrin with caniculi. The structure of ILT may differ largely among AAA patients contrary to previous findings and may reveal large dense fibrin-rich areas deprived of cells, which impair fibrinolysis and stabilize the thrombus size.

An article is a short review which summarize the utility of high sensitive cardiac troponins measurements after coronary artery bypass grafting surgery and their prognostic value in the short- and the long-term survival.

Introduction: Coronary artery bypass graft (CABG) surgery is associated with systemic response and increased concentrations of numerous cytokines. Vascular endothelial growth factor (VEGF) related pathway also seems to be involved in inflammatory response induced by CABG., Objectives: The aim of this study was to analyze the association between the VEGF gene +405 G>C polymorphism (linked to serum VEGF production), and the short-term clinical outcome during the in-hospital period (30 days) in patients undergoing CABG., Patients and Methods: Genotyping for VEGF gene +405 G>C polymorphism was performed in 64 patients with coronary artery disease at a mean age of 66 years (76.6% males), with a mean EuroSCORE (European System for Cardiac Operative Risk Evaluation) of 2.5 (0-2 points: 50% patients, 3-4: 25%, > or =5 points: 25%), who underwent CABG surgery., Results: Twenty-one (33%) patients were homozygous for the +405 G allele, 40 (63%) were heterozygous, and 3 were homozygous for the +405 C allele. Ten patients died during the 30-day follow-up (7 subjects with +405 GG genotype, and the other 3 carriers of the +405 C allele). Using multivariate logistic regression analysis, the risk of death after CABG was increased in patients with +405 GG genotype (odds ratio [OR] = 6.7; 95% confidence interval [CI] 1.5-29.4) and with EuroSCORE > or =5 points (OR = 4.4; 95% CI 1.1-18.1)., Conclusions: The VEGF gene +405 G>C polymorphism might be a prognostic factor of an adverse postoperative course in patients undergoing CABG surgery. Apart from its proangiogenic action, VEGF may have additional, possibly proinflammatory properties.

Background: A common G to T transition in codon 34 with the subsequent valine with leucine replacement in the factor (F) XIII A-subunit affects fibrin formation and stabilisation in vitro. Data on the effects of Leu34 allele on cardiovascular thromboembolic events in vivo are conflicting., Aim: We investigated whether FXIII Val34Leu polymorphism is potent enough to affect fibrin clot properties in patients with advanced coronary artery disease (CAD)., Methods: We studied 113 patients, aged 62.8 +/- 6.1 years, who were scheduled for elective isolated coronary artery bypass grafting surgery (CABG). Patients were compared with 98 healthy age-matched controls. Ex vivo fibrin clot permeability and lysis time (t5oo/o) were determined in citrated plasma., Results: Patients scheduled for CABG had lower clot permeability (9.14 + 1.64 vs. 10.02 + 1.12 x 10(-9) cm2; p = 0.0002) and longer t50%, (8.45 +/- 1.94 vs. 7.63 +/- 1.24 min; p < 0.0001) than controls. The Leu34 carriers, i.e. 9 (8%) Leu34Leu homozygous and 23 (20%) Val34Leu heterozygous subjects, had lower permeability by 23% in the CAD group compared with 81 (72%) patients with Val34Val genotype. A similar intergroup difference was observed for t50%, which was longer in Leu34 carriers (p < 0.0001). The FXIII Leu34 allele frequency in the control group was similar as well as the impact of Leu34 allele on fibrin properties. The effect of FXIII Leu34 allele on permeability and t50%, was not affected by homocysteine, C-reactive protein and fibrinogen levels in CAD patients and controls., Conclusions: Like in healthy subjects, in patients scheduled for CABG, the FXIII Leu34 allele is associated with decreased fibrin clot permeability and efficiency of lysis.

Background: Data on the effects of oral antiplatelet agents on blood coagulation in vivo are conflicting. The platelet glycoprotein (GP) IIIa PlA2 allele has been suggested to modulate antithrombotic actions of clopidogrel., Aim: We investigated whether clopidogrel combined with aspirin affects local thrombin formation and platelet activation triggered by vascular injury., Method: We studied patients with stable coronary artery disease on chronic aspirin therapy randomised to addition of clopidogrel 75 mg/d (n = 30) or continuation of aspirin 100 mg/d (n = 30) for 4 weeks. Markers of thrombin generation [thrombin-antithrombin complexes (TAT) and prothrombin 1.2 fragments (F1.2)] and markers of platelet activation [soluble CD40 ligand (sCD40L) and P-selectin] were determined in the supernatant of blood samples obtained from a microvascular injury site., Results: Total amounts of thrombin markers produced at the site of injury were similar before and after addition of clopidogrel, whereas platelet release of sCD40L and P-selectin was lower during treatment with aspirin + clopidogrel by 33.8% and 27.8% (p < 0.001), respectively. Patients in the highest tertile of reduction in platelet activation had previous myocardial infarction and peripheral arterial disease and released the highest amounts of sCD40L and P-selectin at baseline. TAT and F1.2 generation as well as sCD40L or P-selectin release were not influenced by the presence of the PlA2 allele., Conclusion: Our study shows that clopidogrel combined with aspirin does not reduce thrombin formation following vascular injury, but attenuates platelet sCD40L and P-selectin release.

Objective: The aim of study was to assess whether activation of blood coagulation and platelets is enhanced in aortic stenosis (AS) and if so, to determine factors that might modulate these processes., Patients/methods: Seventy-five patients with AS (48 males, 27 females, aged 65+/-10 years) were enrolled in the study. A control group comprised 75 age- and sex-matched subjects. We determined markers of thrombin generation (thrombin-antithrombin complex [TAT], prothrombin fragment 1+2 [F1+2]), platelet activation (soluble CD40 ligand [sCD40L], beta-thromboglobulin [beta-TG], P-selectin) in peripheral blood plasma. The extent of atherosclerosis in the carotid and coronary arteries was assessed as a potential confounding factor., Results: Mean concentrations of thrombin and platelet markers were higher approximately two-fold in the AS group than in controls (p<0.005 for all comparisons). Maximal gradient was positively associated with TAT (r=0.61, p<0.001), F1+2 (r=0.60, p<0.001), sCD40L (r=0.52, p<0.01) and beta-TG (r=0.70, p<0.001). Aortic valve area (AVA) negatively associated only with one platelet marker, beta-TG (r=-0.30, p<0.05). The presence of concomitant atherosclerotic plaque in the carotid (in 65% of patients) or coronary arteries (in 43% of patients) did not influence thrombin generation and platelet activation in patients with AS., Conclusions: AS predisposes to prothrombotic state. Maximal gradient as an index of turbulent flow associated with activation of coagulation and platelets. In contrast, the small aortic valve area was not closely related to these parameters.

Background and Purpose: We tested the hypothesis that fibrin structure/function is unfavorably altered in patients with cryptogenic ischemic stroke., Methods: Ex vivo plasma fibrin clot permeability, turbidimetry, and efficiency of fibrinolysis were determined in 89 patients with patent foramen ovale (PFO) and a history of first-ever stroke, 58 patients with first-ever stroke and no PFO, and 120 healthy controls., Results: Stroke patients, evaluated 3 to 19 months after the event, and controls did not differ with regard to age, sex, smoking, and fibrinogen. Stroke patients with or without PFO had lower clot permeability (P<0.0001), faster fibrin polymerization (P<0.0001), prolonged clot lysis time (P<0.0001), higher maximum D-dimer levels released from clots (P<0.0001), and maximum rate of D-dimer release (P=0.02) than controls. Time from stroke occurrence showed no association with any clot variables. Scanning electron microscopy of fibrin clots showed increased fiber diameter and density in stroke patients. Clots from stroke patients with PFO were more permeable and showed shorter lysis time compared to those without PFO, and this was related to lower proportion of smokers in the former group., Conclusions: Altered fibrin clot structure and resistance to fibrinolysis are associated with cryptogenic stroke.

Background: The rate of cancer cell growth depends on proliferative activity and on the tumor cell death rate. The study objective was to assess the expressions of Ki-67, PCNA and MCM2 in colorectal cancer and to analyze the correlation between the expressions and chosen anatomo-clinical parameters (patient's age, tumor location, lymph node metastases)., Patients and Methods: The study material included primary tumors pT3 G2 obtained from 55 patients with colorectal cancer. Immunohistochemical investigations were performed using monoclonal antibodies (Ki-67- monoclonal mouse (DAKO) Clone MIB1, PCNA-monoclonal mouse (DAKO) Clone PC10, MCM2-polyclonal goat (Santa Cruz Biotechnology) Sc-9839) directed against human protein Ki-67, PCNA and MCM2., Results: The expressions of Ki-67, PCNA and MCM2 were found to correlate with the presence of lymph node metastases, but not with patient age or tumor location. The expressions of these proteins in the main tumor mass correlated with each other in the majority of patients., Conclusion: The findings allow the assumption that positive expressions of Ki-67, PCNA and MCM2 in the main tumor mass in pathological stage pT3 and degree of histological malignancy G2 may indicate lymph node involvement.

Introduction: Haemostatic factors play an important role in atherothrombosis. Thrombin generation is a crucial stage of blood coagulation., Objectives: Comparison of different thrombin generation markers: thrombin-antithrombin complex (TAT) generation and calibrated automated thrombogram method (CAT). Identification of factors influencing thrombin generation in patients with stable angina (SA) enrolled to the coronary artery bypass grafting (CABG) surgery. Analysis of traditional (age, gender, hypertension and diabetes) and novel (fibrinogen and C-reactive protein [CRP]) risk factors and the antiplatelet therapy (aspirin 75-150 mg/d) in relation to coagulation., Patients and Methods: In 135 SA patients with left main coronary artery stenosis (> 50%) or major epicardial artery stenosis (> 70%), plasma TAT levels, maximal thrombin concentration (C(max)) and endogenous thrombin potential (ETP) were determined. A marker of the platelet activation (beta-thromboglobulin) was also measured., Results: No correlations among TAT, C(max), ETP, risk factors and beta-thromboglobulin were observed. Linear regression model showed that independent predictors of TAT levels were age (beta = 0.5; p = < 0.0001), male gender and diabetes (beta = 0.36; p = 0.02). CRP independently predicted TAT and ETP (beta = -0.24 and beta = 0.22; p < 0.05, respectively), while fibrinogen predicted C(max) (beta = 0.21; p < 0.05). Independent predictors of beta-thromboglobulin were a male gender and aspirin use cessation (beta = 0.46; p = 0.01). Aspirin treatment had no effect on thrombin generation., Conclusions: Age, higher fibrinogen, CRP, diabetes and male gender influence thrombin generation and/or coagulation activation in SA patients. Plasma levels of thrombin-antithrombin complexes do not correlate with the parameters obtained using the calibrated automated thrombogram method (C(max), ETP).

Background: The aortic valve has been the subject of many hemodynamic studies but, to our knowledge, posttranslational modification of human valve proteins has not yet been studied. Thus, the aim of this study was to determine whether any age-related changes in the protein composition of normal human aortic valves and their glycosylation pattern could be observed., Methods: Aortic valves harvested from male cadaveric donors free of cardiovascular diseases were divided into four age groups: I, mean age 21 years; II, 30 years; III, 41 years; IV, 51 years. Proteins were separated by SDS-PAGE and transferred to PVDF membranes. Identification of monosaccharide moieties or oligosaccharide units was performed with the use of eight lectins of narrow specificity: Galantus nivalis agglutinin, Sambucus nigra agglutinin, Maackia amurensis agglutinin, Datura stramonium agglutinin, Aleuria aurantia agglutinin, Arachis hypogeae agglutinin, Phaseolus vulgaris agglutinin, and Lycopersicon esculentum agglutinin., Results: Isolated proteins showed no age-related changes in SDS-PAGE protein profile, contrary to their glycosylation. Protein sialylation, number of tri/tetraantennary complex glycans, proteins having terminal galactose and polylactosaminyl units increased with age, whereas protein fucosylation showed the opposite relationship. Moreover, groups III and IV possessed a larger number of proteins bearing high-mannose and/or hybrid-type glycans, and the quantity of these structures seemed to change, in particular proteins, with the age of donors., Conclusions: Our results clearly demonstrate that glycosylation profile in human aortic proteins is associated with the age of the donor.