Impact of arterial procedures on coagulation and fibrinolysis : a pilot study

Abstract Objective: The main goal of our study was to assess the impact of vascular procedures on the activity of hemostatic and fibrinolytic pathways. Methods: We enrolled 38 patients with ≥ 45 years old undergoing surgery for abdominal aortic aneurysm or peripheral artery disease under general or regional anesthesia and who were hospitalized at least one night after the procedure. Patients undergoing carotid artery surgery and those who had acute bypass graft thrombosis, cancer, renal failure defined as estimated glomerular filtration rate < 30 ml/min/1.73m2, venous thromboembolism three months prior to surgery, or acute infection were excluded from the study. We measured levels of markers of hemostasis (factor VIII, von Willebrand factor:ristocetin cofactor [vWF:CoR], antithrombin), fibrinolysis (D-dimer, tissue plasminogen activator [tPA], plasmin-antiplasmin complexes), and soluble cluster of differentiation 40 ligand (sCD40L) before and 6-12h after vascular procedure. Results: Significant differences between preoperative and postoperative levels of factor VIII (158.0 vs. 103.3, P<0.001), antithrombin (92.1 vs. 74.8, P<0.001), D-dimer (938.0 vs. 2406.0, P=0.005), tPA (10.1 vs. 12.8, P=0.002), and sCD40L (9092.9 vs. 1249.6, P<0.001) were observed. There were no significant differences between pre- and postoperative levels of vWF:CoR (140.6 vs. 162.8, P=0.17) and plasmin-antiplasmin complexes (749.6 vs. 863.7, P=0.21). Conclusion: Vascular surgery leads to significant alterations in hemostatic and fibrinolytic systems. However, the direction of these changes in both pathways remains unclear and seems to be different depending on the type of surgery. A study utilizing dynamic methods of coagulation and fibrinolysis assessment performed on a larger population is warranted

The structure and properties of laser seam stepper system (LSS) welded the low alloy high strength steel DOCOL 1200M with martensitic structure

This paper will present the influence of joining process parameters on the structure and properties of overlapped welded joints of 1.8 mm DOCOL 1200M steel. The obtained welded joints were subjected to micro- and macroscopic metallographic examination and hardness measurement. The visual inspections and non-destructive testing made it possible to develop the field of welding parameters to allow obtaining full penetration joints (depending on requirements) or partial penetration joints. For present welding parameters, i.e. feed rate and weld length, which are constant, the actual length of weld is determined by welding frequency. In each case, the microscopic examinations revealed martensitic structure in the weld area, and with the increase in linear welding energy the size of martensite needles became larger, especially in relation to the base material. In HAZ, the martensitic structure is tempered. It has been shown that with appropriately selected parameters the Laser SEAM Stepper method is suitable for welding the DOCOL 1200M steel. With the increase in welding power, the penetration depth increases

Effects of Shielding Gas Pureness on Quality of Orbital TIG Welded Austenitic Stainless-Steel Joints

Aim of this research was determination of effects of shielding and backing gas pureness on quality of welded joints produced from austenitic stainless-steel grade X5CrNi18-10 (1.4301) pipes Ø 50.8 x 1.5 mm by orbital TIG welding without use of additional material. In the case of stainless steel, it is of importance not only to prepare shielding of the molten metal pool but as well protection of welded joint root from oxygen, which causes formation of colorful oxide layers. Presence of oxidized layer primarily decreases corrosion resistance of stainless-steel. Performed examination included: chemical composition of welded join material, delta ferrite testing, non-destructive joint testing, visual testing with discoloration assessment from face and root side (acc. to Danish Force Technology Institute report 93.34 and American ASME BPE-2012 norm), radiographic testing, destructive welded joint testing. Metallurgical shielding of the welded joint face was produced with Argon 5.0 pure, with a flow rate of 8 dm3/min. Root of welded joint was at first protected with Argon 5.0 pure, then argon-atmospheric air mixtures were used. Backing gas flow rate was set to achieve a relative pressure of 300 Pa. Quantity of residual oxygen in gas mixture was selected based on Danish Force Technology Institute report 93.34

Assessment of the laser beam welding of galvanized car body steel with an additional organic protective layer

This study discusses the effect of laser beam welding parameters on the structure, mechanical properties and corrosion resistance of 1.2 mm thick galvanized sheets made of low-carbon steel DC04 provided with a ZE36/36 GardoprotectOC2BU organic coating. The test laser beam butt welded joints were made without the filler metal, using a variable welding rate, where linear welding energy was restricted within the range of 30 J/mm to 90 J/mm. The joints were subjected to non-destructive tests, destructive tests and corrosion resistance tests. The tests revealed the possibility of making joints meeting the criteria specified in the ISO 15614-11 standard. Regardless of the value of linear welding energy applied in the process, all the joints were characterised by high mechanical and plastic properties. It was noticed that an increase in linear welding energy from 30 J/mm to 90 J/mm was accompanied by the widening of the weld and that of the heat-affected zone (HAZ). In addition, an increase in linear welding energy was accompanied by a decrease in the maximum weld hardness to approximately 250 HV0.2. In the HAZ, hardness was restricted within the range of 190 HV0.2 to 230 HV0.2 and decreased along with increasing linear welding energy. In the static tensile test, regardless of the value of linear welding energy, the test specimen ruptured in the base material. In the bend test, regardless of the value of linear welding energy, a bend angle of 180° was obtained without partial tear or scratches; unit elongation was restricted within the range of 29% to 42%. The electrochemical tests and experiments performed in the salt spray chamber revealed the very high effectiveness of the corrosion protections against aggressive chloride ions

A clinical profile and factors associated with severity of the disease among Polish patients hospitalized due to COVID-19 — an observational study

Introduction: The coronavirus disease 2019 (COVID-19) is one of the greatest clinical challenges of the last decades. Clinical factors associated with severity of the disease remain unclear. The aim of the study was to characterize Polish patients hospitalized due to COVID-19 and to evaluate potential prognostic factors of severe course of the disease.Material and methods: An observational study was conducted from March to July 2020 in the Pulmonology and Allergology Department of the University Hospital in Kraków, Poland. Consecutive patients with confirmed SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) infection were enrolled, and data about past medical history, signs and symptoms, laboratory results, imaging studies results, in-hospital management and outcomes was prospectively gathered.Results: The study sample comprised 100 patients at the mean age of 59.2 (SD 16.1) years among whom 63 (63.0%) were male. Among them 10 (10.0%) died, 47 (47%) presented respiratory failure, 15 (15.0%) were transferred to the intensive care unit, 17 (17.0%) developed acute kidney injury, 7 (7.0%) had sepsis and 10 (10.0%) were diagnosed with pulmonary embolism. Multivariable analysis revealed age (OR 1.1; 95% CI 1.01–1.15), body mass index (BMI; OR 1.24; 95% CI 1.01–1.53), modified early warning score (MEWS; OR 3.95; 95% CI 1.48–12), the highest d-dimer value (OR 1.73; 95% CI 1.03–2.9) and lactate dehydrogenase (LDH; OR 1.16; 95% CI 1.03–1.3) to be associated with severe course of COVID-19.Conclusion: This observational study showed that almost half of hospitalized patients with COVID-19 developed respiratory failure in the course of the disease. Increasing age, BMI, MEWS, d-dimer value and LDH concentration were associated with the severity of COVID-19

Time from admission to surgery in Polish patients with hip fractures : temporal trends in the last decade and association with duration of hospitalization and in-hospital mortality

Introduction: Hip fracture is an important cause of morbidity and mortality among elderly patients worldwide. It poses a particular challenge for healthcare systems with limited financial and human resources. Objectives: The aim of the study was to assess factors associated with the length of hospital stay and in-hospital mortality, focusing on the time from admission to surgery. The secondary goal was to assess temporal trends in the intervals of admission to surgery between 2010 and 2011 and in 2019. Patients and methods: This was a cross-sectional study enrolling patients aged 65 years or older who underwent surgery for hip fracture between January 2010 and October 2011 in 12 Polish hospitals. Demographic and clinical data, dates of hospital admission and surgery as well as information about in-hospital death were gathered. We additionally searched the databases of the same 12 hospitals for patients hospitalized due to hip fracture between January and June 2019 and recorded the dates of admission and surgery. Results: We included 381 patients who underwent surgery in 2010 and 2011 and 761 patients hospitalized in 2019. In a multivariable analysis, including age, sex, and diagnosis of dementia, we observed association between time from admission to surgery and higher in-hospital mortality and longer hospital stay. There was a decrease in proportion of patients undergoing surgery within 2 days from admission (52.8% vs 44.3%; P = 0.007) between 2010 to 2011 and in 2019. Conclusions: In-hospital mortality and length of hospitalization were associated with time from admission to surgery in patients undergoing surgery for hip fracture. We observed an alarming trend towards an increase in the admission–surgery interval

Concentration of meropenem in patients with sepsis and acute kidney injury before and after initiation of continuous renal replacement therapy : a prospective observational trial

Background The effect of renal replacement therapy on drug concentrations in patients with sepsis has not been fully elucidated because the pharmacokinetic properties of many antimicrobials are influenced by both pathophysiological and treatment-related factors. The aim of this study was to determine meropenem concentrations in patients with sepsis before and after the initiation of continuous venovenous hemodialysis with regional citrate anticoagulation (RCA-CVVHD). Methods The study included 15 critically ill patients undergoing RCA-CVVHD due to sepsis-induced acute kidney injury. All participants received 2 g of meropenem every 8 h in a prolonged infusion lasting 3 h. Meropenem concentrations were measured in blood plasma using high-performance liquid chromatography coupled with tandem mass spectrometry. Blood samples were obtained at six-time points prior to and at six-time points after introducing RCA-CVVHD. Results The median APACHE IV and SOFA scores on admission were 118 points (interquartile range [IQR] 97-134 points) and 19.5 points (IQR 18-21 points), respectively. There were no significant differences in the plasma concentrations of meropenem measured directly before RCA-CVVHD and during the first 450 min of the procedure. The drug concentration reached its peak 2 h after initiating the infusion and then steadily declined. Conclusions The concentration of high-dose meropenem (2 g every 8 h) administered in a prolonged infusion was similar before and after the introduction of RCA-CVVHD in patients with sepsis who developed acute kidney injury

Increased activity of the sterol branch of the mevalonate pathway elevates glycosylation of secretory proteins and improves antifungal properties of Trichoderma atroviride.

Some Trichoderma spp. have an ability to inhibit proliferation of fungal plant pathogens in the soil. Numerous compounds with a proven antifungal activity are synthesized via the terpene pathway. Here, we stimulated the activity of the mevalonate pathway in T. atroviride P1 by expressing the Saccharomyces cerevisiae ERG20 gene coding for farnesyl pyrophosphate (FPP) synthase, a key enzyme of this pathway. ERG20-expressing Trichoderma strains showed higher activities of FPP synthase and squalene synthase, the principal recipient of FPP in the mevalonate pathway. We also observed activation of dolichyl phosphate mannose (DPM) synthase, an enzyme in protein glycosylation, and significantly increased O- and N-glycosylation of secreted proteins. The hyper-glycosylation of secretory hydrolases could explain their increased activity observed in the ERG20 transformants. Analysis of the antifungal properties of the new strains revealed that the hydrolases secreted by the transformants inhibited growth of a plant pathogen, Pythium ultimum more efficiently compared to the control strain. Consequently, the biocontrol activity of the transgenic strains, determined as their ability to protect bean seeds and seedlings against harmful action of P. ultimum, was also improved substantially