Changes of the serum properties and its effect on the endothelial cells restoration in patients with chronic disease treated with sulodexide.

OBJECTIVE: Inflammation and endothelial dysfunction are important venous changes in patients with chronic venous disease (CVD). The use of the venoactive drugs remains an important treatment modality for patients with CVD, reducing the severity of the CVD-related symptoms and swelling but also reducing inflammation and protecting endothelial cells. In this research, the effects of the serum obtained from patients with CVD before and after sulodexide treatment were evaluated for in vivo and in vitro inflammatory markers and endothelial cell function. METHODS: Inflammatory markers (IL-6, matrix metalloproteinase-9 [MMP-9], vascular cell adhesion molecule-1 [VCAM-1], and von Willebrand factor [vWF]) from the incompetent great saphenous veins (GSVs) and from the systemic venous circulation were studied in 10 patients with CVD (C2s) before and after 2 months of sulodexide (2 × 500 LSU/d) therapy. Serum from pretreatment and following sulodexide treated patients was evaluated for in vitro cultured human umbilical vein endothelial cell function. RESULTS: The serum collected from lower leg incompetent GSVs had significantly elevated levels of VCAM-1 (+29%, P < .001) compared with the serum from the systemic circulation. Endothelial cells exposed to the serum from the incompetent lower leg veins of the untreated CVD patients demonstrated higher stimulated synthesis of MMP-9 (+17%, P < .01), as well as increased markers of senescence (prolongation of population doubling time, ß-galactosidase activity, and expression of p21 and p53 genes). CVD serum-induced senescent endothelial cells had a higher expression of genes regulating IL-6, MMP-9, VCAM-1, and vWF synthesis. The overall proinflammatory effect on endothelial cells by the serum collected from the incompetent GSVs was stronger as compared with the serum from the systemic circulation. Serum collected from the veins after sulodexide treatment caused lower levels of endothelial cell inflammatory markers as well as respective gene expression than serum obtained at the beginning of the study (before sulodexide treatment). Sulodexide application also reduced the inflammatory secretory activity of the senescent endothelial cells. Sulodexide treatment resulted in the decrease of the majority of the studied inflammatory parameters in both lower limb incompetent vein and systemic blood. CONCLUSIONS: In patients with CVD, there are significant differences between circulating inflammatory markers analyzed from the lower leg incompetent GSV segments compared with the systemic circulation, indicating a higher inflammatory condition in CVD. Treatment with sulodexide reduces the proinflammatory and endothelial cell activation properties of the serum from patients with CVD. CLINICAL RELEVANCE: The study documented the significant proinflammatory human vascular endothelial cell activation when exposed to the serum collected from the varicose veins as compared with the serum from the systemic circulation in patients with chronic venous disease (CVD). The inflammatory marker expression, endothelial dysfunction, and endothelial cell senescence transformation can be successfully controlled and downregulated by patients' exposure to the glycosaminoglycan (sulodexide) treatment. Further studies are needed to confirm if glycosaminoglycan application can prevent further CVD clinical progression due to potential CVD-related pathological processes' modulation and their downregulation.

Reversed urban-rural gradient in COVID-19 seroprevalence and related factors in a nationally representative survey, Poland, 29 March to 14 May 2021.

BackgroundWe anticipated that people in rural areas and small towns with lower population density, lower connectivity and jobs less dependent on social interaction will be less exposed to COVID-19. Still, other variables correlated with socioeconomic inequalities may have a greater impact on transmission.AimWe investigated how COVID-19 affected rural and urban communities in Poland, focussing on the most exposed groups and disparities in SARS-CoV-2 transmission.MethodsA random digit dial sample of Polish adults stratified by region and age was drawn from 29 March to 14 May 2021. Serum samples were tested for anti-S1 and anti-N IgG antibodies, and positive results in both assays were considered indicative of past infection. Seroprevalence estimates were weighted to account for non-response. Adjusted odds ratios (AORs) were calculated using multivariable logistic regression.ResultsThere was serological evidence of infection in 32.2% (95% CI: 30.2-34.4) of adults in rural areas/small towns (< 50,000 population) and 26.6% (95% CI: 24.9-28.3) in larger cities. Regional SARS-CoV-2 seroprevalence ranged from 23.4% (95% CI: 18.3-29.5) to 41.0% (95% CI: 33.5-49.0) and was moderately positively correlated (R = 0.588; p = 0.017; n = 16) with the proportion of respondents living in rural areas or small cities. Upon multivariable adjustment, both men (AOR = 1.60; 95% CI: 1.09-2.35) and women (AOR = 2.26; 95% CI: 1.58-3.21) from these areas were more likely to be seropositive than residents of larger cities.ConclusionsWe found an inverse urban-rural gradient of SARS-CoV-2 infections during early stages of the COVID-19 pandemic in Poland and suggest that vulnerabilities of populations living in rural areas need to be addressed.

A real-world study of a calcium alginate dressing for various wound etiologies on clinical performance, usability, and safety.

INTRODUCTION: Complex wounds require a moist wound healing environment and exudate control. Alginate dressings are highly absorbable and available as sheets for superficial wounds and ropes for deeper wounds. OBJECTIVE: This study evaluates the real-world performance of a conformable CAD containing mannuronic acid for various wound types. MATERIALS AND METHODS: The usability and safety of the tested CAD were evaluated in adult patients with various wound types. Further endpoints were clinician satisfaction with dressing application and suitability for wound type and their opinion of the tested CAD compared with other dressings of this type. RESULTS: The study included 83 patients with exuding wounds (42 male [51%]; 41 female [49%]) and a mean age of 74.54 years (SD ± 15.54 years). Thirteen clinicians (76%) (x = 1.24) rated the first CAD application as very easy, 4 (24%) as easy, and 1 (6%) as not easy. The time for dressing application was ranked as very good (x = 1.65) by 8 clinicians (47%), while 7 (41%) rated the time for application as good, and 2 (12%) gave a satisfactory rating. CONCLUSION: The CAD sheet and rope were safe to use and fit for purpose in wounds of various etiologies. In addition, the dressing was easy to handle and remove, formed a gel faster than other alginates, and outperformed other previous products.

Evaluation of the Properties and Microstructure of Thick-Walled Welded Joint of Wear Resistant Materials.

The research was conducted on a thick-walled welded joint between the HTK 900H wear-resistant steel plates and the A6 cast profile. The aim of the experiment was to produce a joint with the relevant performance requirements, i.e., a good abrasion resistance joint in the weld face area while ensuring its proper plasticity. The welded joint was made using the MAG PULSE and the high-performance MAG TANDEM methods under automated conditions using the linear welding energy ranging from 1.2 to 2.2 kJ/mm for the different joint regions. The scope of the research included both non-destructive and destructive testing. The non-destructive visual (VT), magnetic-particle (MT), and ultrasonic (UT) tests revealed a good quality of the welded joint with no significant welding imperfections. The microstructure of the welded joint in the weld zone was characterized by a dominant volume fraction of martensite/bainite. The measurement of hardness near the face of the weld confirmed obtaining similar values for this parameter. The HTK 900H steel was characterized by hardness at the level of 383 HV10, whereas the A6 cast-328 HV10, and the weld-276 HV10. At the same time, the analyzed joint showed high ductility in the range of 86 to 159 J. The tests carried out showed that the linear energy control allowed a welded joint with the required performance characteristics to be obtained.

Implementation of Alternative Mineral Additives in Low-Emission Sustainable Cement Composites.

The influence of four naturally occurring mineral additives (zeolite, diatomite, trass and bentonite) on the hydration and properties of cement pastes and mortars was investigated. The materials change the phase composition, heat of hydration (determined by calorimetry) and mechanical properties of composites. After 28 days, the amount of Ca(OH)2 was reduced by up to 23% and up to 35% more C-S-H was formed, as proved by TG measurements. Differences were observed in the kinetics of heat release, especially for 25% of the addition. In the calorimetric curves, an additional exothermic effect is observed, related to the alteration in the hydration of C3A in cement. From the point of view of beneficial influence on mechanical properties of mortars, the additives could be ranked as follows: bentonite < diatomite, zeolite < trass after 2 days and bentonite < diatomite < trass < zeolite after 28 days of curing. The highest compressive strength (58.5 MPa) was observed for the sample with a 10% addition of zeolite. Zeolite, trass, bentonite and diatomite are all pozzolanic materials; however, their activity varies to an extent due to the differences in their specific surface area and the content of the amorphous phase, responsible for the pozzolanic reaction.

Foundation Piles-A New Feature for Concrete 3D Printers.

Foundation piles that are made by concrete 3D printers constitute a new alternative way of founding buildings constructed using incremental technology. We are currently observing very rapid development of incremental technology for the construction industry. The systems that are used for 3D printing with the application of construction materials make it possible to form permanent formwork for strip foundations, construct load-bearing walls and partition walls, and prefabricate elements, such as stairs, lintels, and ceilings. 3D printing systems do not offer soil reinforcement by making piles. The paper presents the possibility of making concrete foundation piles in laboratory conditions using a concrete 3D printer. The paper shows the tools and procedure for pile pumping. An experiment for measuring pile bearing capacity is described and an example of a pile deployment model under a foundation is described. The results of the tests and analytical calculations have shown that the displacement piles demonstrate less settlement when compared to the analysed shallow foundation. The authors indicate that it is possible to replace the shallow foundation with a series of piles combined with a printed wall without locally widening it. This type of foundation can be used for the foundation of low-rise buildings, such as detached houses. Estimated calculations have shown that the possibility of making foundation piles by a 3D printer will reduce the cost of making foundations by shortening the time of execution of works and reducing the consumption of construction materials.

Two-Step Synthesis of Heptacyclo[6.6.0.02,6 .03,13 .04,11 .05,9 .010,14 ] tetradecane from Norbornadiene: Mechanism of the Cage Assembly and Post-synthetic Functionalization.

A selective and scalable two-step approach to the dimerization of norbornadiene (NBD) into its thermodynamically most stable dimer, heptacyclo[6.6.0.02,6 .03,13 .04,11 .05,9 .010,14 ] tetradecane, (HCTD) is reported. Calculations indicate that the reaction starts with the Rh-catalyzed stepwise homo Diels-Alder cyclisation of NBD into its exo-cis-endo dimer. Treatment of this compound with acid promotes its evolution to HCTD via a [1,2]-sigmatropic rearrangement. The assemblies of 7,12-disubstituted cages from 7-(alkyl/aryl) NBDs, as well as the selective post-synthetic C-H functionalization of the core HCTD scaffold at position C1, or positions C1 and C4 are described.

Calibration of Steel Rings for the Measurement of Strain and Shrinkage Stress for Cement-Based Composites.

Concrete shrinkage is a phenomenon that results in a decrease of volume in the composite material during the curing period. The method for determining the effects of restrained shrinkage is described in Standard ASTM C 1581/C 1581M-09a. This article shows the calibration of measuring rings with respect to the theory of elasticity and the analysis of the relationship of steel ring deformation to high-performance concrete tensile stress as a function of time. Steel rings equipped with strain gauges are used for measurement of the strain during the compression of the samples. The strain is caused by the shrinkage of the concrete ring specimen that tightens around steel rings. The method allows registering the changes to the shrinkage process in time and evaluating the susceptibility of concrete to cracking. However, the standard does not focus on the details of the mechanical design of the test bench. To acquire accurate measurements, the test bench needs to be calibrated. Measurement errors may be caused by an improper, uneven installation of strain gauges, imprecise geometry of the steel measuring rings, or incorrect equipment settings. The calibration method makes it possible to determine the stress in a concrete sample leading to its cracking at specific deformation of the steel ring.

Effect of Curing Methods on Shrinkage Development in 3D-Printed Concrete.

Technological developments in construction have led to an increase in the use of 3D modelling using CAD environments. The popularity of this approach has increased in tandem with developments in industry branches which use 3D printers to print concrete based printing materials in construction, as these allow freedom in shaping the dimensions of supporting elements. One of the biggest challenges for researchers working on this highly innovative technology is that of cement material shrinkage. This article presents the findings of research on an original method of measuring deformations caused by shrinkage in 3D-printed concrete elements. It also discusses the results of tests on base mixes, as well as comparisons between the influence of internal and external curing methods on the development of deformations and their final outcomes. Furthermore, the article discusses differences between deformations formed after seven days of hardening without curing, with those which occur when two common, traditional concrete curing methods are used: foil insulation and shrinkage reducing admixtures. In addition, the article examines the effects of internal curing on the 1, 7, 14, 21 and 28 day mechanical properties of concrete, in accordance with EN 196-1 and EN 12390-2. Studies have shown that the optimal amount of shrinkage reducing admixtures is 4% (in relation to the mass of cement), resulting in a reduction in total shrinkage of 23%. The use of a shrinkage reducing admixture in 3D-printed concrete does not affect their strength after 28 days, but slows the strength development during the first 7 days.

Automation in the Construction of a 3D-Printed Concrete Wall with the Use of a Lintel Gripper.

Developments in the automation of construction processes, observable in recent years, is focused on speeding up the construction of buildings and structures. Additive manufacturing using concrete mixes are among the most promising technologies in this respect. 3D concrete printing allows the building up of structure by extruding a mix layer by layer. However, the mix initially has low capacity to transfer loads, which can be particularly troublesome in cases of external components that need to be placed on top such as precast lintels or floor beams. This article describes the application of additive manufacturing technology in the fabrication of a building wall model, in which the door opening was finished with automatic lintel installation. The research adjusts the wall design and printing process, accounting for the rheological and mechanical properties of the fresh concrete, as well as design requirements of Eurocode. The article demonstrates that the process can be planned precisely and how the growth of stress in fresh concrete can be simulated, against the strength level developed. The conclusions drawn from this research will be of use in designing larger civil structures. Furthermore, the adverse effects of concrete shrinkage on structures is also presented, together with appropriate methods of control.

The Effect of Service on Microstructure and Mechanical Properties of HR3C Heat-Resistant Austenitic Stainless Steel.

The physical metallurgical tests were performed on the test samples made of HR3C steel, taken from a section of a pipeline in the as-received condition and after approximately 26,000 h of service at 550 °C. In the as-received condition, the test material had austenitic microstructure with numerous large primary Z-phase precipitates inside the grains. The service of the test steel mainly contributed to the precipitation processes inside the grains and at the grain boundaries. After service, the following precipitates were identified in the microstructure of the test steel: Z-phase (NbCrN) and M23C6 carbides. The Z-phase precipitates were observed inside the grains, whereas M23C6 carbides - at the boundaries where they formed the so-called continuous grid. The service of the test steel contributed to the growth of the strength properties, determined both at room and elevated temperature (550, 600 °C), compared to the as-received condition. Moreover, the creep properties of HR3C steel after service were higher than those of the material in the as-received condition. The increase in the strength properties and creep resistance was connected with the growth of strengthening of the test steel by the precipitation of Z-phase and M23C6 carbides.

Characterization of acute otitis media otopathogens before the introduction of the pneumococcal conjugated vaccine into the national immunization program in Poland.

BACKGROUND: Bacterial etiologic data for acute otitis media (AOM) otopathogens in Poland are scarce. The aim of this study was to determine the bacterial etiology and antibiotic susceptibility patterns of otopathogens in children prior to the introduction of the pneumococcal conjugated vaccine (PCV) into the national immunization program (NIP) in Poland. METHODS: Demographic and laboratory data of children < 5 years old who underwent tympanocentesis due to AOM in Nieklanska Hospital Warsaw between 2010 and 2016, were collected. All middle ear fluids (MEF) cultures were processed at the hospital according to conventional culture methods. RESULTS: Out of 940 MEF cultures, 407 (43.3%) were positive for 419 isolates. The most common etiologies of positive cultures were: S. pneumonaie, nontypeable H. infuenzae (NTHi), and S. pyogenes. Children aged 12-23 months had significantly more S. pneumoniae and NTHi positive cultures than children <12 months of age. S. pneumoniae isolates non-susceptible to penicillin, erythromycin, and clindamycin, declined over the study period (2010-2016). CONCLUSIONS: This is the largest dataset of MEF isolates from AOM patients in Poland, collected during the pre-PCV period. These data can help determine the appropriate treatment for AOM patients and can serve as a baseline for the period before the introduction of PCV to the NIP in Poland.

Microstructure and Mechanical Properties of Inconel 740H after Long-Term Service.

Inconel 740H is a nickel-based alloy for pressure components of ultra-supercritical boilers. Its chemical composition and strengthened matrix, as well as corrosion resistance, provide the highest creep resistance among the materials recommended for use in high-performance pressure components of power units. This paper investigates the changes in the microstructure and mechanical properties after ageing at 700 and 750 °C for 1000, 10,000, 20,000, and 30,000 h. Observation of the microstructure was performed using scanning and transmission electron microscopy. The identification of existing precipitates was conducted by X-ray phase analysis. The effects of time and ageing at elevated temperatures on the mechanical properties and precipitation process in the test alloy are discussed. The presented results are part of the material characteristics of the new-generation alloys to be used in the design of pressure equipment for steam boilers, as well as in diagnostic work during operation.

Regio- and Stereoselective Chlorocyanation of Alkynes.

A variety of terminal and internal alkynes were converted regio- and stereoselectively into (Z)-3-chloroacrylonitriles by treatment with BCl3 in the presence of stoichiometric amounts of imidazolium thiocyanates. These products could be readily functionalized to provide useful building blocks, thus demonstrating the synthetic value of the method. Preliminary mechanistic studies suggest initial activation of the cationic thiocyanate by the Lewis acid, followed by electrophilic attack of the alkyne. The syn addition of a chloride to the vinyl cation intermediate and final elimination of the thiourea unit afford the desired chloroacrylonitriles.

α-Dicationic Chelating Phosphines: Synthesis and Application to the Hydroarylation of Dienes.

A series of new P^P-chelating ligands constituted by a dicationic -[P(H2Im)2]+2 unit (H2Im = 1,3-dimethyl-4,5-dihydroimidazol-2-ylidene) and a -PPh2 group connected through structurally different backbones have been synthesized. Evaluation of their reactivity toward different metal centers provides evidence that the dicationic fragment, otherwise reluctant to coordinate metals, readily participates in the formation of chelates when embedded into such a scaffold. Moreover, it significantly enhances the Lewis acidity of the metals to which it coordinates. This property has been used to develop a Rh catalyst that efficiently triggers the hydroarylation of dienes with electron-rich aromatic molecules. Kinetic studies and deuterium-labeling experiments, as well as density functional theory calculations, were performed in order to rationalize these findings.

Ruthenium Catalysts Supported by Amino-Substituted N-Heterocyclic Carbene Ligands for Olefin Metathesis of Challenging Substrates.

N-Heterocyclic carbene (NHC) ligands IMesNMe2 and IMes(NMe2)2 derived from the well-known IMes ligand by substituting the carbenic heterocycle with one and two dimethylamino groups, respectively, were employed for the synthesis of second-generation Grubbs- and Grubbs-Hoveyda-type ruthenium metathesis precatalysts. Whereas the stability of the complexes was found to depend on the degree of dimethylamino-substitution and on the type of complex, the backbone-substitution was shown to have a positive impact on their catalytic activity in ring-closing metathesis, with a more pronounced effect in the second-generation Grubbs-type series. The new complexes were successfully implemented in a number of challenging olefin metathesis reactions leading to the formation of tetra-substituted C=C double bonds and/or functionalized compounds.

Stable ruthenium indenylidene complexes with a sterically reduced NHC ligand.

Stable and active Ru olefin metathesis catalyst 7 bearing a sterically reduced NHC ligand was synthesized. Upon action of pyridine, 7 forms complex 24, the first example of an Ru­indenylidene catalyst bearing a labile pyridine ligand and a sterically less demanding NHC ligand.

Perioperative treatment with octreotide minimizes technical complications after enteric conversion of bladder-drained pancreas transplants.

We review our experience with enteric conversion of previously bladder-drained pancreas transplants (PTx) using a short perioperative course of octreotide (OCT). Between July 1994 and December 2001, 45 consecutive primary bladder-drained PTx were performed. Immunosuppression consisted of a combination of tacrolimus, mycophenolate mofetil and steroids after induction with monoclonal or polyclonal antibodies. A total of 16 patients underwent enteric conversion at an average of 3 months after the initial transplant. Each patient received OCT perioperatively. We report no technical complications with the exception of one superficial wound infection and good early and late PTx survival rates. Perioperative treatment with octreotide is well tolerated and may reduce technical complications while performing enteric conversion of previously bladder-drained PTx.

Simultaneous pancreas-kidney transplant from living related donor: a single-center experience.

BACKGROUND: Simultaneous pancreas and kidney transplantation (SPK) from cadaveric donors has become a widely accepted therapeutic option for insulin-dependent uremic patients. In 1996 the first SPK from a live donor was performed. This procedure offers the advantage of a better immunologic match, reduced cold ischemia injury, and decreased waiting time. As such, it is an attractive alternative treatment for diabetic patients with end-stage nephropathy with an available living donor. METHODS: We performed six SPKs from living-related donors. There were four men and two women among the recipients; median age was 34 (range, 29-39) years. All donors were recipients' siblings with excellent HLA matching. Donors underwent standardized metabolic workup, anti-insulin and anti-islet antibody assays, and computed tomography of the abdomen. Both donors and recipients were treated with octreotide for 5 days perioperatively. After transplantation, the patients were maintained on tacrolimus-based immunosuppression, with the exception of one recipient of SPK from an identical twin, who received cyclosporine monotherapy. RESULTS: All the donors are doing well and have normal renal function and blood glucose levels. One-year patient, renal, and pancreatic graft survival rates were 100%, 100%, and 83%, respectively. Acute kidney rejection was documented in two patients, and both recovered completely after OKT3 therapy. No rejection of pancreatic graft has been documented. Except for one patient who lost the graft because of hemorrhagic pancreatitis, all recipients maintained serum glucose levels at less than 130 mg/dL without insulin therapy. No major surgical complications such as graft thrombosis, intra-abdominal infection, or abscess were reported. CONCLUSIONS: Living donor SPK can represent a successful alternative to cadaveric donor SPK. The procedure can be performed safely in the donor and with low morbidity in the recipient.