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Studies on biocompatibility of AISI 316LVM steel indicate the need to eliminate the nickel from the surface and replace it with other elements of improved biocompatibility. Therefore, in the presented work selected physicochemical and mechanical properties of the diffusive nitrocarburized layer formed by plasma potential by means of an active screen made of the Fe-Cr-Ni were studied. In the paper we present results of microstructure and phase composition of the layers, roughness, and surface wettability, potentiodynamic pitting corrosion resistance, penetration of ions into the solution as well as mechanical properties. The studies were conducted for the samples of both mechanically polished and nitrocarburized surfaces, after sterilization, and exposure to the Ringer's solution. Deposition of the nitrocarburized layer increased the contact angle, surface roughness, surface hardness, and corrosion resistance with respect to the polished surfaces. The nitrocarburized layer is a barrier against the ions release into the solution and sterilization and exposure to Ringer solution. The obtained results showed beneficial increase of both mechanical and electrochemical properties of the deposited layer, and thus the applicability of the proposed method of surface treatment of the 316LVM steel for short-term implants after sterylization. [ABSTRACT FROM AUTHOR]

Complex analysis of concentration and form of occurrence such metals as Zn, Pb, Fe and Cu in slags formed during a current zinc production in the Imperial Smelting Process (ISP) is a possible basis for development of optimal recovery technology. For this purpose studies of slags from the current production of the Shaft Furnace Unit and of the Lead Refining of the "Miasteczko Śląskie" Zinc Smelting Plant were carried out. The studies results show that slags includes high concentrations of: Zn from 0,064% to 1,680%, Pb from 10,56% to 50,71%, Fe from 0,015% to 2,576%, Cu from 7,48% to 64,95%, and change in a broad range. This slags show significant heterogeneity, caused by intermetallic phases (Zn - Pb, Cu - Zn, Cu - Pb) formed on the surface thereof. It is so possible that slag can be a potential source of this metals recovery. [ABSTRACT FROM AUTHOR]

Degradation of polyethylene was performed over MCM-41 molecular sieves modified with heteropoly acid H3PW12O40 (HPW) and its caesium salt CsHPW12O40 (CsHPW). High silica zeolite ZSM-5 has also been used as degradation catalyst. The applied catalysts (HPW/MCM-41, CsHPW/MCM-41 and ZSM-5 zeolite) resulted in lowering of temperature of HDPE degradation when compared to the thermal pyrolysis as well as influenced the distribution of the products formed as a result of the cracking process. HPW/ MCM-41 use resulted in low amount of gas products and almost 80 wt.% of liquids while cracking over HZSM- 5 produced gas hydrocarbons with selectivity about 50 wt.%. Liquid product obtained in the presence of HPW/MCM-41 comprised aliphatic hydrocarbons (olefins and paraffins) while cracking carried out over ZSM-5 zeolite resulted mainly in the formation of aromatic compounds. [ABSTRACT FROM AUTHOR]

Background/aim: Cardiovascular diseases (CVD) are the leading cause of death worldwide. In 2019, 523 million people were diagnosed with CVD, with 18.6 million deaths. Improved treatment and diagnostics could reduce CVD's impact. Irisin (Ir) is crucial for heart function and may be a biomarker for heart attack. Ir is a glycoprotein with sugar residues attached to its protein structure. This glycosylation affects Ir stability, solubility, and receptor interactions on target cells. Its secondary structure includes a fibronectin type III domain, essential for its biological functions. Ir helps cardiomyocytes to respond to hypoxia and protects mitochondria. The aim of the study was to determine the FNDC5 gene expression level and the Ir level in HL-1 cardiomyocytes subjected to hypoxia., Materials and Methods: We examined the effect of hypoxia on the expression levels of the FNDC5 gene and those of Ir in mouse cardiomyocytes of the HL-1 cell line. Real-time PCR (RT-PCR) was used to estimate the expression levels of the FNDC5 gene. Western blot and immunofluorescence methods were used to analyze the Ir protein levels., Results: Analyses showed an increased Ir level in HL-1 cardiomyocytes in response to hypoxia. This is the first study to confirm the presence of Ir in HL-1 cells., Conclusion: The observed increase in Ir expression in murine cardiomyocytes is associated with the hypoxic environment and can be potentially used to diagnose hypoxia and CVD., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Solketal, a widely used glycerol-derived solvent, can be efficiently synthesized through heterogeneous catalysis, thus avoiding the significant product losses typically encountered with aqueous work-up in homogeneous catalysis. This study explores the catalytic synthesis of solketal using solid acid catalysts derived from recovered carbon blacks (rCBs), which are obtained through the pyrolysis of end-of-life tires. This was further converted into solid acid catalysts through the introduction of acidic functional groups using concentrated H 2 SO 4 or 4-benzenediazonium sulfonate (BDS) as sulfonating agents. Additionally, post-pyrolytic rCB treated with glucose and subsequently sulfonated with sulfuric acid was also prepared. Comprehensive characterization of the initial and modified rCBs was performed using techniques such as elemental analysis, powder X-ray diffraction, thermogravimetric analysis, a back titration method, and both scanning and transmission electron microscopy, along with X-ray photoelectron spectroscopy. The catalytic performance of these samples was evaluated through the batch mode glycerol acetalization to produce solketal. The modified rCBs exhibited substantial catalytic activity, achieving high glycerol conversions (approximately 90%) and high solketal selectivity (around 95%) within 30 min at 40 °C. This notable activity was attributed to the presence of -SO 3 H groups on the surface of the functionalized rCBs. Reusability tests indicated that only rCBs modified with glucose demonstrated acceptable catalytic stability in subsequent acetalization cycles. The findings underscore the potential of utilizing end-of-life tires to produce effective acid catalysts for glycerol valorization processes.

The results of the content determination of the selected trace elements Ti, Sr, Ba, Zn, Pb, Cu, S, P, Cr, Cd, Ni, Zr, Mo, Rb, Sc, Y, and REEs were presented in this article. Studies were carried out to define the purity of limestones. The elements were measured in the carbonate minerals of Middle Triassic limestones of the Opole Silesia in Poland, using ICP-MS and X-ray fluorescence (XRF). Moreover, the contents of Sc and REY were also determined by electron microprobe analysis. These methods are characterized by high accuracy and precision of the measurement. The research results show that the contents of trace elements vary from below 1 ppm up to some hundreds ppm. The highest content was measured for strontium and the lowest for barium, elements characteristic of aragonite. Their occurrence indicates the presence of aragonite in the primary carbonate material. Some trace elements form substitutions in clay or carbonate minerals. Zn, Pb, Cu, Mo, and Ni may be associated with sulfides, and Ti and Cr may be associated with oxides. Sc and REY usually substitute Ca ions in calcite. The contents of measured Ce, Nd, Sm, Dy, Er, and Y vary from below 1 ppm up to 6 ppm, and Sc from 0 ppm to 10 ppm.

Disorders of cardiomyocyte metabolism play a crucial role in many cardiovascular diseases, such as myocardial infarction, heart failure and ischemia-reperfusion injury. In myocardial infarction, cardiomyocyte metabolism is regulated by mitochondrial changes and biogenesis, which allows energy homeostasis. There are many proteins in cells that regulate and control metabolic processes. One of them is irisin (Ir), which is released from the transmembrane protein FNDC5. Initial studies indicated that Ir is a myokine secreted mainly by skeletal muscles. Further studies showed that Ir was also present in various tissues. However, its highest levels were observed in cardiomyocytes. Ir is responsible for many processes, including the conversion of white adipose tissue (WAT) to brown adipose tissue (BAT) by increasing the expression of thermogenin (UCP1). In addition, Ir affects mitochondrial biogenesis. Therefore, the levels of FNDC5/Ir in the blood and myocardium may be important in cardiovascular disease. This review discusses the current knowledge about the role of FNDC5/Ir in cardiovascular disease.

This article presents the mineralogical and chemical characteristics of zinc and lead smelting slags, with particular reference to the slags formed during the simultaneous production of Zn and Pb by the Imperial Smelting Process. These slags, because of the presence of many metals in their composition, mainly in the form of crystalline phases, are a valuable source for their extraction. Slags from Zn-Pb metallurgy are processed on an industrial scale using pyrometallurgical and hydrometallurgical methods, alongside which a number of experiments conducted to recover metals as efficiently as possible, including bioleaching experiments.

Irisin (Ir) is an adipomyokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. Additionally, FNDC5/Ir is suspected of inhibiting the epithelial-mesenchymal transition (EMT) process. This relationship has been poorly studied for breast cancer (BC). The ultrastructural cellular localizations of FNDC5/Ir were examined in BC tissues and BC cell lines. Furthermore, we compared serum levels of Ir with FNDC5/Ir expression in BC tissues. The aim of this study was to examine the levels of EMT markers, such as E-cadherin, N-cadherin, SNAIL, SLUG, and TWIST, and to compare their expression levels with FNDC5/Ir in BC tissues. Tissue microarrays with 541 BC samples were used to perform immunohistochemical reactions. Serum levels of Ir were assessed in 77 BC patients. We investigated FNDC5/Ir expression and ultrastructural localization in MCF-7, MDA-MB-231, and MDA-MB-468 BC cell lines and in the normal breast cell line (Me16c), which was used as the control. FNDC5/Ir was present in BC cell cytoplasm and tumor fibroblasts. FNDC5/Ir expression levels in BC cell lines were higher compared to those in the normal breast cell line. Serum Ir levels did not correlate with FNDC5/Ir expression in BC tissues but were associated with lymph node metastasis (N) and histological grade (G). We found that FNDC5/Ir correlated moderately with E-cadherin and SNAIL. Higher Ir serum level is associated with lymph node metastasis and increased grade of malignancy. FNDC5/Ir expression is associated with E-cadherin expression level.

The rapid growth and division of cancer cells are associated with mitochondrial biogenesis or switching to glycolysis. ERRα, PGC-1α and irisin/FNDC5 are some of the proteins that can influence these processes. The aim of this study was to determine the correlation of these proteins in non-small cell lung cancer (NSCLC) and to investigate their association with clinicopathological parameters. Immunohistochemistry reactions were performed on tissue microarrays (860 NSCLC, 140 non-malignant lung tissue). The normal fibroblast cell line (IMR-90) and lung cancer cell lines (NCI-H1703 and NCI-H522) were used as co-cultures. The mRNA levels of FNDC5 and ESRRA (encoding ERRα) were assessed in IMR-90 cells after co-culture with lung cancer cells. We observed a decreased level of ERRα with an increase in tumor size (T), stages of the disease, and lymph node metastases (N). In the adenocarcinoma (AC) subtype, patients with a higher ERRα expression had significantly longer overall survival. A moderate positive correlation was observed between FNDC5 mRNA and ESRRA mRNA in NSCLCs. The expression of FNDC5 mRNA in IMR-90 cells increased after 24 h, and ESRRA gene expression increased after 48 h of co-culture. The ERRα receptor with PGC-1α participates in the control of FNDC5/irisin expression. Normal fibroblasts revealed an upregulation of the FNDC5 and ESRRA genes under the influence of lung cancer cells.

Irisin is a myokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. FNDC5 and irisin levels have been poorly studied in the tumor tissues of breast cancer (BC). The aim of this study was to determine the levels of irisin expression in BC tissues and compare them to clinicopathological factors and Ki-67 and PGC-1α expression levels. Tissue microarrays (TMAs) with 541 BC tissues and 61 samples of non-malignant breast disease (NMBD; control) were used to perform immunohistochemical reactions. FNDC5 gene expression was measured in 40 BC tissue samples, 40 samples from the cancer margin, and 16 NMBD samples. RT-PCR was performed for the detection of FNDC5 gene expression. Higher irisin expression was found in BC patients compared to normal breast tissue. FNDC5/irisin expression was higher in patients without lymph node metastases. Longer overall survival was observed in patients with higher irisin expression levels. FNDC5/irisin expression was increased in BC tissues and its high level was a good prognostic factor for survival in BC patients.

Pancreatic cancers are among of the most lethal types of neoplasms, and are mostly detected at an advanced stage. Conventional treatment methods such as chemotherapy or radiotherapy often do not bring the desired therapeutic effects. For this reason, natural compounds are increasingly being used as adjuvants in cancer therapy. Polyphenolic compounds, including resveratrol, are of particular interest. The aim of this study is to analyze the antiproliferative and pro-apoptotic mechanisms of resveratrol on human pancreatic cells. The study was carried out on three human pancreatic cancer cell lines: EPP85-181P, EPP85-181RNOV (mitoxantrone-resistant cells) and AsPC-1, as well as the normal pancreatic cell line H6c7. The cytotoxicity of resveratrol in the tested cell lines was assessed by the colorimetric method (MTT) and the flow cytometry method. Three selected concentrations of the compound (25, 50 and 100 µM) were tested in the experiments during a 48-h incubation. TUNEL and Comet assays, flow cytometry, immunocytochemistry, confocal microscopy, real-time PCR and Western Blot analyses were used to evaluate the pleiotropic effect of resveratrol. The results indicate that resveratrol is likely to be anticarcinogenic by inhibiting human pancreatic cancer cell proliferation. In addition, it affects the levels of Bcl-2 pro- and anti-apoptotic proteins. However, it should be emphasized that the activity of resveratrol was specific for each of the tested cell lines, and the most statistically significant changes were observed in the mitoxantrone-resistant cells.

Irisin (Ir) is an adipomyokine that is involved in the regulation of metabolic processes. It also influences processes related to inflammation, including cancer. Initially, Ir was considered a hormone secreted by skeletal muscles in response to physical exercise. Further studies showed that Ir is also present in other healthy tissues, organs, and plasma. It influences the change in phenotype of white adipose tissue (WAT) into brown adipose tissue (BAT). It increases mitochondrial biogenesis and affects the expression of thermogenin (UCP1). This adipomyokine has also been found in many tumor tissues and in the serum of cancer patients. Studies are underway to determine the association between Ir and carcinogenesis. It has been confirmed that Ir inhibits in vitro proliferation, migration, and invasion. It is involved in the inhibition of epithelial-mesenchymal transition (EMT). Additionally, Ir affects the expression of the transcription factor Snail, which is involved in EMT, and inhibits transcription of the gene encoding E-cadherin, which is characteristic of epithelial-derived cells. Many studies have been performed to determine the role of Ir in physiological and pathological processes. Further detailed studies should determine more precisely the effect of Ir on the body in health and disease.

In this study, we aimed to determine the effect of long-term exposure to artificial urine on the physical properties of CoCrMo alloy with biodegradable heparin-releasing polymeric coatings. Variants of polymer coatings of poly(L,L-lactide-ɛ-caprolactone) (P(L,L-L/CL)) and poly(D,L-lactide-ɛ-caprolactone) (P(D,L-L/CL)) constituting the base for heparin-releasing (HEP) polyvinyl alcohol (PVA) coatings were analyzed. The coatings were applied by the dip-coating method. Heparin was used to counteract the incrustation process in the artificial urine. The study included tests of wettability, resistance to pitting and crevice corrosion, determination of the mass density of metal ions penetrating into the artificial urine, and the kinetics of heparin release. In addition, microscopic observations of surface roughness and adhesion to the metal substrate were performed. Electrolytically polished CoCrMo samples (as a reference level) and samples with polymer coatings were used for the tests. The tests were conducted on samples in the initial state and after 30, 60, and 90 days of exposure to artificial urine. The analysis of the test results shows that the polymer coatings contribute by improving the resistance of the metal substrate to pitting and crevice corrosion in the initial state and reducing (as compared with the metal substrate) the mass density of metal ion release into the artificial urine. Moreover, the PVA + HEP coating, regardless of the base polymer coatings used, contributes to a reduction in the incrustation process in the first 30 days of exposure to the artificial urine.

The inhibition of the corrosion of metal implants is still a challenge. This study aimed to increase the corrosion resistance of Ti6Al7Nb alloy implants through surface modification, including grinding, sandblasting, and anodic oxidation followed by the deposition of a polymer coating. The aim of the work was to determine the influence of biodegradable polymer coatings on the physico-chemical properties of a Ti6Al7Nb alloy used for short-term implants. Biodegradable coatings prepared from poly(glycolide-caprolactone) (P(GCap)), poly(glycolide ε-caprolactone-lactide) (P(GCapL)), and poly(lactide-glycolide) (PLGA) were applied in the studies. The dip-coating method with three cycles of dipping was applied. Corrosion resistance was assessed on the basis of potentiodynamic studies. The studies were carried out on samples after 30, 60, and 90 days of exposure to Ringer's solution. Surface topography, wettability, and cytotoxicity studies were also carried out. The degradation process of the base material was evaluated on the basis of the mass density of the metal ions released to the solution. The results indicated the influence of the coating type on corrosion resistance. In addition, a beneficial effect of the polymer coating on the reduction of the density of the released metal ions was found, as compared to the samples without polymer coatings. The obtained results provide basic knowledge for the development of polymer coatings enriched with an active substance. The presence of ciprofloxacin in the coating did not reduce the corrosion resistance of the metal substrate. Moreover, the cytotoxicity test using the extract dilution method demonstrated that the implants' coatings are promising for further in vitro and in vivo studies.

V-containing silica SBA-3 mesoporous catalysts were prepared by means of one-pot hydrothermal procedure with NH 4 VO 3 or VOSO 4 as vanadium precursors under various acidic medium of the reaction mixture (pH < 1, 2.2 or 3.1). The combined spectral techniques (DR UV-vis, FTIR, EPR) as well H 2 -TPR allowed to determine the nature of vanadium species in the studied samples. A successful incorporation of vanadium into the structure of silica SBA-3 was attained for the samples with low V content (<1 wt%), whereas the V-rich samples ( i.e. >5 wt%) exhibited the presence of isolated vanadium and also of polynuclear surface species. The resulting V-bearing samples contain the Brønsted and Lewis acidic centres evidenced by FTIR spectra of adsorbed pyridine and by catalytic activity for 2-propanol decomposition and cumene cracking. Ammonia TPD allowed to estimate the number and strength of acid sites in regards to the vanadium content. Propene oxidation with N 2 O revealed noticeable activity of the synthesised V-SBA-3 samples in epoxidation reaction. On the basis of TOF analysis indicating the activity of particular vanadium ions it seems that not all of the introduced V atoms take part in the formation of mild electrophilic oxygen species responsible for propene oxide formation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The aim of the study was to determine the influence of long term exposure to Ringer's solution of biodegradable polymer coatings containing an active substance on the Ti6Al7Nb alloy substrate on the physical and chemical properties of the coatings and the degradation process of the metal substrate. The studies used poly(L-lactide-co-trimethylene carbonate) P(L/TMC), poly(L-lactide-co-trimethylene carbonate-glycolide) P(L/TMC/G) and poly(D,L-lactide-glycolide) (PLGA) coatings applied to the anodically oxidized Ti6Al7Nb alloy by means of dipping method (1, 2 and 3 dips). The polymer coatings contained ciprofloxacin. Roughness and wettability tests were carried out on the substrate and polymer coatings, the pitting corrosion resistance of the substrate and samples with polymer coating was determined, the number of metallic ions released to the solution from the coated and uncoated samples was determined as well as the adhesion of polymer coatings. The research was supplemented by microscopic observations. The results of the research indicate different influence of exposure to Ringer's solution on the physical and chemical properties of biodegradable polymer coatings containing ciprofloxacin and the course of the degradation process of the metal substrate.

NiTi shape memory alloys are characterized by relatively good biocompatibility primarily thanks to their ability to self-passivate. However, before they can be used as medical implants for long term use, they need to undergo treatment aimed at producing layers on their surface that are superior to spontaneously formed oxide layers and that would increase their resistance to corrosion, limit nickel ion release from the surface (metallosis) and have the capability to shape their biological properties depending on the application. Furthermore, cardiac implants require addressing the issue of blood clotting on the surface. Treatment in glow-discharge low temperature plasma makes it possible to produce titanium layers with a structure and properties that are controlled via process parameters. In addition, antithrombogenic properties can be improved by depositing a carbon coating via the RFCVD process. The aim of the study was to investigate the structure, surface topography, adhesive properties, wettability, surface free energy and evaluate metallosis after producing TiO 2 and a-C:N:H + TiO 2 composite layers on NiTi alloy. The capabilities of AFM microscopes in studying the adhesive properties of a surface were also highlighted in the study. The study shows that the produced surface layers are capable of significantly reducing metallosis. Furthermore, in contrast to NiTi in its initial state, layers of nanocrystalline TiO 2 titanium oxide (rutile) with a homogeneous structure demonstrate greater adhesion strength and more developed surface in the microscale, which facilitates the formation of an a-C:N:H coating. Therefore the formation of a coating of a-C:N:H amorphous carbon on NiTi alloy that has previously been oxidised in low-temperature plasma may prove to be a favourable solution in terms of using NiTi alloy to produce cardiac implants., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Human papillomavirus (HPV) belongs to the Papillomaviridae family and infects squamous cells and mucous membranes of humans. Various studies conducted over the last years have shown a correlation between HPV infection and carcinogenesis process. The DNA of the virus is detected in approximately 20% of cancers of the upper respiratory tract. The presence of HPV in cancerous lesion of the larynx varies depending on the procedure applied for sample collection and the viral DNA detection method. The high variance in the frequency of HPV detection is observed even among results obtained with the use of PCR reaction. It varies between 3 and 85%. HPV is also the etiological factor of laryngeal papillomas in both children and adults. However, a considerable amount of research demonstrates that 1-7% of the larynx papillomas in adults undergo transformation into squamous cell carcinoma. The aim of the study was to summarize the current state of knowledge regarding the presence of the HPV virus in the larynx as well as its participation in malignant transformation.