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The efficient use of waste from food processing industry is one of the innovative approaches within sustainable development, because it can be transferred into added value products, which could improve economic, energetic and environmental sectors. In this context, the squid pen waste from seafood industry was used as raw material to obtain nanofibrous β-chitin films. In order to extend functionality of obtained films, elderberry extract obtained from biomass was added at different concentrations. The tensile strength of chitin-elderberry extract films was improved by 52%, elongation at break by 153% and water vapor barrier by 65%. The obtained material showed distinct color change when subjected to acidic or basic solutions. It was proven by CIELab color analysis that all color changes could be easily perceived visually. In addition, the obtained nanofibrous film was successfully used to monitor the freshness of Hake fish. Namely, when the film was introduced in a package that contained fresh fish, its color was efficiently changed within the time during the storage at 4 °C. The obtained results demonstrated that food processing waste could be efficiently valorized, and could give sustainable food package design as a spoilage indicator of high protein food.

In high-grade serous ovarian carcinoma (HGSC), deleterious mutations in DNA repair gene RAD51C are established drivers of defective homologous recombination and are emerging biomarkers of PARP inhibitor (PARPi) sensitivity. RAD51C promoter methylation (meRAD51C) is detected at similar frequencies to mutations, yet its effects on PARPi responses remain unresolved. In this study, three HGSC patient-derived xenograft (PDX) models with methylation at most or all examined CpG sites in the RAD51C promoter show responses to PARPi. Both complete and heterogeneous methylation patterns were associated with RAD51C gene silencing and homologous recombination deficiency (HRD). PDX models lost meRAD51C following treatment with PARPi rucaparib or niraparib, where a single unmethylated copy of RAD51C was sufficient to drive PARPi resistance. Genomic copy number profiling of one of the PDX models using SNP arrays revealed that this resistance was acquired independently in two genetically distinct lineages. In a cohort of 12 patients with RAD51C-methylated HGSC, various patterns of meRAD51C were associated with genomic “scarring,” indicative of HRD history, but exhibited no clear correlations with clinical outcome. Differences in methylation stability under treatment pressure were also observed between patients, where one HGSC was found to maintain meRAD51C after six lines of therapy (four platinum-based), whereas another HGSC sample was found to have heterozygous meRAD51C and elevated RAD51C gene expression (relative to homozygous meRAD51C controls) after only neoadjuvant chemotherapy. As meRAD51C loss in a single gene copy was sufficient to cause PARPi resistance in PDX, methylation zygosity should be carefully assessed in previously treated patients when considering PARPi therapy. Significance: Homozygous RAD51C methylation is a positive predictive biomarker for sensitivity to PARP inhibitors, whereas a single unmethylated gene copy is sufficient to confer resistance.

The ageing process is accompanied by numerous changes in the brain of dogs, such as accumulation of amyloid, fibrosis of blood vessel walls and meninges, accumulation of lipofuscin, and the presence of polyglucosan bodies (PGBs), satellitosis and neuronophagia. In this study, the presence of lipofuscin and PGBs in various parts of the brain in dogs of different sexes and ages was examined. For this purpose, brain samples were stained using haematoxylin eosin, modified Ziehl Neelsen and Periodic acid Schiff (PAS) methods. Lipofuscin was visualised by Ziehl Neelsen and PAS methods of specific staining on the same brain tissue segments. Lipofuscin had accumulated in 93% of old (more than 10 years old) dog brains, mostly in neurons of the medulla oblongata. The percentage of age-related lipofuscin pigment in other examined brain tissue segments was lower than in the medulla oblongata. There was a small difference in the percentage of lipofuscin-positive individuals between the two staining methods. The presence of PGBs was established by the PAS method for the vast majority (about 93%) of the old dogs (more than 10 years old), while PGBs were not detected in the group of young dogs (up to 5 years old). However, PGBs occurred in all examined segments of the dog’s brain tissues (for each of the tissue types, from 90% to 93% of dogs were positive for PGBs). The results obtained the oldest dogs (15 years old) harboured PGBs both extracellularly and intracellularly, while in other dogs, only extracellular PGBs were seen. Lipofuscin was accumulated mostly in large neurons of olivary nuclei of the medulla oblongata. PGBs were confirmed in all examined segments of the brain tissue of dogs more than 10 years old. This is one of the numerous indications that old dogs could be a very good animal model for studying the normal ageing process or neurodegenerative diseases. Proces starenja prate brojne promene u mozgu pasa kao što su nagomilavanje amiloida, fibroza zida krvnih sudova i moždanih ovojnica, nakupljanje lipofuscina i prisustvo poliglukoznih tela (PGB), satelitoza i neuronofagija. U ovom radu ispitivano je prisustvo lipofuscina i PGB u različitim delovima centralnog nervnog sistema kod pasa različitog pola i starosti. Uzorci mozga obojeni su hematoksilin eozinom, modifikovanom Ziehl Neelsen metodom i perjodna kiselina-Schiff (PAS) metodom. Lipofuscin je modifikovanom Ziehl Neelsen i PAS metodom specifično dokazan u istim segmentima moždanog tkiva. Dobijeni rezultati pokazuju da je lipofuscin akumuliran uglavnom u neuronima produžene moždine kod 93% pasa. Zastupljenost pigmenta u ostalim segmentima mozga bio je niži u poređenju sa produženom moždinom. Korišćenjem obe metode bojenja, ustanovljena je mala razlika u procentu pozitivnih jedinki. Prisustvo PGB dokazano je PAS metodom kod velikog broja (oko 93%) pasa eksperimentalne grupe, dok u kontrolnoj grupi njihovo prisustvo nije ustanovljeno. U svim ispitivanim segmentima moždanog tkiva kod pasa iz eksperimentalne grupe, dokazana su PGB i to od 90% do 93%. Dobijeni rezultati ukazuju da su kod najstarijih pasa iz eksperimentalne grupe PGB bila lokalizovana i van ćelije i unutar nje, a kod drugih samo ekstracelularno. Lipofuscin je akumuliran uglavnom u velikim neuronima olivarnih jedara produžene moždine. PGB su dokazana u svim ispitivanim segmentima moždanog tkiva pasa starijih od 10 godina. Ovo je jedan od brojnih dokaza da stari psi predstavljaju dobar animalni model za proučavanje normalnog procesa starenja ili neurodegenerativnih bolesti.

The effect of undissociated acetic acid on the integrity of an iron carbonate (FeCO3) layer formed on platinum and X65 steel substrates is investigated. Experiments were conducted using buffered solutions with 0.8 mM to 5 mM undissociated acetic acid. For the platinum substrates, changes in the FeCO3 layer were monitored via in situ electrochemical quartz crystal microbalance (EQCM) measurements. This investigation was supported by performing electrochemical experiments, under comparable conditions, on the X65 steel specimens, linking the integrity of FeCO3 layer to its corrosion protection effect. The EQCM measurements revealed that the addition of acetic acid, at all concentrations tested here, caused partial dissolution of the FeCO3 layer. The dissolution occurred selectively, with the outer layer dissolving first, leaving behind an inner FeCO3 layer at the end of the immersion experiment. The electrochemical results revealed that introducing the acetic acid caused a sudden increase in the corrosion rate, which over time returned to a lower value similar in magnitude to that seen before addition of the acetic acid. This was attributed to the protection provided by the inner FeCO3 layer, which was only mildly affected by the addition of acetic acid and was able to repair over time. It was proven that the dissolution of the protective FeCO3 layer in the presence of acetic acid was not due to a small pH change but rather due to the formation of ferrous acetate complexes and changes in ionic strength, which decreases the FeCO3 saturation values.

The contamination of animal feed with mycotoxins is a worldwide problem in the animal husbandry, but it also represents a serious threat for the whole food chain. The health of both animals and humans is potentially endangered. From this point of view aflatoxins are a class of mycotoxins especially well known. Therefore, new strategies to combat these natural contaminants are constantly being developed. The most applied method to protect animals against aflatoxicosis is the utilization of feed additives aimed to adsorb aflatoxins. In order to estimate adsorbing potential of feed additive “MycoStop DUPLO”, designed for the prevention and/or alleviation of adverse effects of aflatoxin B1 in animal nutrition, in vitro trial was conducted. As a result of the experiment, conducted at pH 5 during 120 minutes of incubation at 37°C, the optimal formulation of the adsorbent was revealed. This product, in low concentration and in the presence of high amounts of toxin, met the stringent European regulation requirements for minimum 90% aflatoxin binding efficiency (90.1% achieved with 0.02% adsorbent and 4 mg/L toxin concentration). In higher adsorbent (0.2%), and lower toxin (0.2 mg/L) conditions, adsorption was 99.6%. Such outcome indicated the validity of in vitro experimental approach which can serve as a reliable fast tool for triage of adsorbents and preselect them for in vivo tests.

Background Quinoa (Chenopodium quinoa Willd) is an Andean original pseudocereal with high nutritional value. During quinoa processing, large amounts of saponin-rich husks byproducts are obtained. Quinoa saponins, which are biologically active, could be used for various agriculture purposes. Silver nanoparticles have increasingly attracted attention for the management of crop diseases in agriculture. In this work, silver nanoparticles are synthesized by a sustainable and green method, using quinoa husk saponin extract (QE) to evaluate their potential for application in agriculture as biostimulants. Results Quinoa extract was obtained and characterized by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Sixteen saponin congeners were successfully identified and quantified. The QE obtained was used as a reducing agent for silver ions to synthesize silver nanoparticles (QEAgNPs) under mild conditions. The morphology, particle size, and stability of Ag nanoparticles were investigated by transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-visible), energy-dispersive X-ray (EDS), zeta potential, and Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR). Ultraviolet-visible spectroscopy measurements confirmed the formation of silver nanoparticles in the presence of QE, with estimated particle sizes in a range between 5 and 50 nm. According to the zeta potential values, highly stable nanoparticles were formed. The QE and QEAgNPs (200-1000 μg/mL) were also tested in radish seed bioassay to evaluate their phytotoxicity. The seed germination assays revealed that QEAgNPs possessed a phytostimulant effect on radish seeds in a dose-dependent manner, and no phytotoxicity was observed for both QE and QEAgNPs. Conclusion Silver nanoparticles obtained by a so-called 'green' method could be considered as good candidates for application in the agricultural sector for seed treatment, or as foliar sprays and plant-growth-promoters. © 2020 Society of Chemical Industry.

The recent developments in mechanistic understandings of mild steel corrosion in the presence of carboxylic acids, carbon dioxide, and hydrogen sulfide, when place side by side, reveal a simple, universal mechanism despite all the differences conventionally presumed for these corroding systems. These findings are recast into a generic mechanistic view of corrosion in aqueous weak acid solutions herein. In this mechanism, the buffering effect resulting from the chemical dissociation reaction inside the boundary layer, is highlighted as an inherent property of all weak acids. The validity of this mechanism was further examined through mathematical experimentation based on a comprehensive mechanistic model. It is shown that this mechanism is able to account for a wide range of characteristic behavior of cathodic currents, including those previously associated with the direct reduction reactions. The results are ultimately presented as a simple and generic categorization of weak acids based on their pKa values to serve as a basis to assess the detrimental effect of any weak acid on mild steel corrosion in aqueous acidic solutions.

Acquired PARP inhibitor (PARPi) resistance in BRCA1- or BRCA2-mutant ovarian cancer often results from secondary mutations that restore expression of functional protein. RAD51C is a less commonly studied ovarian cancer susceptibility gene whose promoter is sometimes methylated, leading to homologous recombination (HR) deficiency and PARPi sensitivity. For this study, the PARPi-sensitive patient-derived ovarian cancer xenograft PH039, which lacks HR gene mutations but harbors RAD51C promoter methylation, was selected for PARPi resistance by cyclical niraparib treatment in vivo. PH039 acquired PARPi resistance by the third treatment cycle and grew through subsequent treatment with either niraparib or rucaparib. Transcriptional profiling throughout the course of resistance development showed widespread pathway level changes along with a marked increase in RAD51C mRNA, which reflected loss of RAD51C promoter methylation. Analysis of ovarian cancer samples from the ARIEL2 Part 1 clinical trial of rucaparib monotherapy likewise indicated an association between loss of RAD51C methylation prior to on-study biopsy and limited response. Interestingly, the PARPi resistant PH039 model remained platinum sensitive. Collectively, these results not only indicate that PARPi treatment pressure can reverse RAD51C methylation and restore RAD51C expression, but also provide a model for studying the clinical observation that PARPi and platinum sensitivity are sometimes dissociated.

It is estimated that the world’s population will enlarge by 25% by the middle of this century, resulting in the food production increase by at least 60%. Intensifying egg production is one of the most affordable solutions to provide animal protein. Among many other efforts to improve the quality of eggs, special attention is paid to attempts to provide a better endurance and strength of eggshell, due to the fact that the production of eggs with broken, cracked or soft shells incurs significant economic losses. One of the most important factors to achieve this goal is careful adjustment of calcium in the diet of laying hens, but the nutritional role of calcium is closely linked to that of phosphorus and the effect of vitamin D. The aim of the experiment was to determine whether two different nutritional supplements of calcium, applied in drinking water of laying hens for two weeks have any significant influence on the shell egg quality. Statistically very significant difference in egg production was observed in the treatment with the product containing calcium and phosphorus. On the other hand, the product consisting of calcium and vitamin D3 had no beneficial impact on the egg parameters. Based on the obtained results and literature data, it can be concluded that the amount and source of calcium in the diet of laying hens is a very complex and not fully solved issue. Therefore, especially keeping in mind the duration of the experiment, additional research is needed on this subject.

Carbon dioxide (CO2) corrosion mitigation is a challenge in the oil and gas industry. In order to decrease the severity of CO2 corrosion of carbon steel pipelines and equipment, different mitigation practices are recommended. One such strategy is the application of surface-active chemical inhibitors. The aim of this research was to evaluate the inhibition effectiveness of decanethiol in a CO2-saturated aqueous electrolyte (1 wt% NaCl). The inhibition properties of decanethiol were evaluated by electrochemical measurements (linear polarization resistance, potentiodynamic sweeps, and electrochemical impedance spectroscopy) and the steel surface was characterized by scanning electron microscopy. The obtained data show that decanethiol can successfully prevent corrosion of carbon steels in a CO2 environment. An inhibition mechanism was also proposed based on adsorption characteristics and inhibitor film formation.

The current study is aimed at proposing a common mechanism of localized corrosion of mild steel in H2S containing aqueous environments, by utilizing experimental findings reported in a number of st...

The objective of the present study was to identify and quantify the key issues that affect the integrity of carbon steel in high-pressure CO2 and CO2/H2S environments and to establish potential cor...

In the context of H2S corrosion of mild steel, the direct electrochemical reduction of H2S is currently believed to be the main contribution of this species to cathodic currents. That is perhaps due to the distinct behavior of the cathodic polarization curves observed in the presence of H2S, as compared to those obtained in strong acids solutions or in the presence of other weak acids such as carboxylic acids and carbonic acid. In the presence of aqueous H2S, the cathodic polarization curves show a “double wave” shape, that is widely considered to be the result of the direct reduction of H2S. In the present study, the mechanism of H2S corrosion of mild steel is theoretically investigated with the focus on the buffering ability of H2S. It is shown that all characteristic behaviors of cathodic currents that were previously associated with the direct reduction of H2S, including the “double wave”, can be fully explained in terms of the H2S dissociation reaction and its buffering effect. In order to further evaluate this mechanistic argument, a comprehensive mathematical model for the H2S system was developed and the calculated cathodic polarization curves were compared with the existing experimental data in the open literature. The results showed that the model, built with H+ reduction as the sole cathodic reaction, is able to reasonably capture all characteristic behavior of cathodic currents, further supporting this mechanistic argument.

Some recent efforts toward studying adsorption, aggregation, and self-assembly of corrosion inhibitor molecules near metal/water interfaces via classical molecular simulations are reported. Two dif...

Paper description: Chronic exposure to glucose-based peritoneal dialysis (PD) solutions causes peritoneal injury as a result of upregulation of vascular endothelial growth factor (VEGF) with proinflammatory and proangiogenetic activities. Few studies have examined the in vivo effects of VEGF on the peritoneal membrane in humans. Observed significant inverse correlations between drained dialysate VEGF concentrations, residual diuresis and residual renal function at chronic PD onset point to the importance of preserved residual renal function in achieving VEGF clearance. The predictive value of drained dialysate VEGF in identifying patients with preserved transport characteristics of peritoneal membrane and efficacious long term PD maintenance is emphasized. Abstract: Vascular endothelial growth factor (VEGF), a powerful angiogenetic agent crucial for microvascular hyperpermeability and neoangiogenesis in the peritoneum, is associated with increased solute transport rates in chronic peritoneal dialysis (PD) patients. We investigated the correlation between serum and drained dialysate (dd) concentrations of VEGF and the transport characteristics of peritoneal membrane and dialysis quality in 20 patients with end-stage renal failure at the beginning and after six months of PD. The serum VEGF (sVEGF) concentration rose significantly (149.33±116.71 pg/mL vs 239.36±102.23 pg/mL; p=0.012) and ddVEGF concentration increased slightly (38.44±50.47 pg/mL vs 43.55±51.10 pg/mL) during the first 6 months of PD. At the beginning of chronic PD, ddVEGF concentrations correlated inversely with the peritoneal equilibrium test (PET) glucose (R=-0.565; p=0.009) and creatinine (R=-0.506; p=0.023) and residual renal function (RRF) (R=-0.691; p=0.001); sVEGF concentrations inversely correlated with PET creatinine (R=-0.457; p=0.043) and residual diuresis (RD) (R=-0.691; p=0.001). After 6 months of treatment, ddVEGF concentrations correlated directly with PET creatinine (R=0.450; p=0.047), and inversely with RRF (R=-0.552; p=0.012) and residual renal weekly Kt/V (R=-0.488; p=0.029). The sVEGF concentration inversely correlated with RD (R=-0.589; p=0.006). High ddVEGF at the beginning of PD is predictive of adverse alterations of the peritoneal membrane, i.e. increased transport rate of glucose and creatinine. ddVEGF values may help to identify patients who will preserve adequate transport characteristics of the peritoneal membrane and maintain successful long-term PD. https://doi.org/10.2298/ABS181120061J Received: November 20, 2018; Revised: December 19, 2018; Accepted: December 22 2018; Published online: December 27, 2018 How to cite this article: Jovanovic NŽ, Žunic SS, Trbojevic-Stankovic JB, Lausevic ŽD, Nesic DM, Stojimirovic BB. The relationship between vascular endothelial growth factor (VRGF) in the serum and drained dialysate with the quality of peritoneal dialysis and peritoneal membrane transport rates. Arch Biol Sci. 2018;71(1):187-94.

The conventionally accepted mechanism of CO2 corrosion considers the direct reduction of carbonic acid as the main process that results in the higher corrosion rates as compared to that observed in strong acid solutions with the same pH. The present study is an attempt to further elucidate the underlying electrochemical mechanisms of CO2 corrosion. In this regard, the mechanism of CO2 corrosion was investigated based on the cathodic and anodic polarization behavior of mild steel in CO2-saturated solutions at elevated pressures. The examination of charge transfer controlled cathodic currents showed that the direct reduction of carbonic acid is insignificant at the condition of the present study. Additionally, the iron dissolution reaction was found to be significantly affected by the presence of CO2, particularly over the transition and pre-passivation ranges. A comprehensive mathematical model based on the presented mechanistic understanding of the system was developed and used for further quantitative examinations. The present mechanistic model was shown to be able to represent the main mechanistic features of polarization curves and predict the corrosion rates with reasonable accuracy.

In the present study, the implementation of a comprehensive mechanistic predictive model for corrosion of mild steel in the oil and gas transmission pipelines is described. The present model simultaneously accounts for all major corrosion scenarios, including CO2 corrosion, H2S corrosion, and corrosion in the presence of organic acid and also incorporates the effect of corrosion product layer formation, including iron carbonate and iron sulfide. With this approach, the present model mechanistically reflects the mainstream understanding of corrosion in such environments and can be readily used to predict the corrosion rates in industrial applications. The model was implemented by using a generalized mathematical and programming approach that has built-in flexibility to add new chemical species and additional reactions in the future. The model was designed to make it easy to extend and cover an even broader range of conditions than it currently does, such as higher temperatures and pressures, nonideal solut...

International audience; β-chitin was isolated from marine waste, giant Humboldt squid Dosidicus gigas, and further converted to nanofibers by use of a collider machine under acidic conditions (pH 3). The FTIR, TGA, and NMR analysis confirmed the efficient extraction of β-chitin. The SEM, TEM, and XRD characterization results verified that β-chitin crystalline structure were maintained after mechanical treatment. The mean particle size of β-chitin nanofibers was in the range between 10 and 15 nm, according to the TEM analysis. In addition, the β-chitin nanofibers were converted into films by the simple solvent-casting and drying process at 60 °C. The obtained films had high lightness, which was evidenced by the CIELAB color test. Moreover, the films showed the medium swelling degree (250–290%) in aqueous solutions of different pH and good mechanical resistance in the range between 4 and 17 MPa, depending on film thickness. The results obtained in this work show that marine waste can be efficiently converted to biomaterial by use of mild extractive conditions and simple mechanical treatment, offering great potential for the future development of sustainable multifunctional materials for various industrial applications such as food packaging, agriculture, and/or wound dressing.

Purpose To conduct a systematic review to evaluate the influence of materials and surfaces used for dental implant abutments on the proliferation of human gingival fibroblasts. Materials and methods The focus question of this review was: Which material/surface characteristics used for dental implant abutments influence/enhance proliferation of human gingival fibroblasts? The Medline/PubMed, Embase, and Cochrane Library databases were searched using "gingiva," "fibroblasts," "proliferation," and "dental implant abutments" as main keywords with AND/OR as Boolean operators. In vitro studies reporting 3 to 4 or 6 to 7 days of cell proliferation, surface hydrophilicity, and roughness were included. A quality assessment of the selected studies was performed using the web-based Science in Risk Assessment and Policy (SciRAP) tool. Results The search identified 1,144 studies, and 44 were eligible for inclusion. The average reporting quality SciRAP score was 82.87 ± 10.68, and the average methodologic quality SciRAP score was 87.35 ± 10.55. Machined, polished, and coated titanium and zirconia surfaces were most commonly investigated. Several studies analyzed aluminum oxide, cobalt-chrome-molybdenum alloy, lithium disilicate, polyether ether ketone, polymer-infiltrated ceramic network, and bioglass. The best cell proliferation was observed on zirconia and on titanium harboring nanotubules or microgrooves. UV treatment, polydopamine, and nitride coatings also improved cell proliferation. Due to the heterogeneity of the data, no correlation could be established between cell profileration and surface hydrophilicity or roughness. However, surface roughness in the range of Ra = 15 to 145 nm and Sa = 19 to 500 nm on titanium and zirconia proved most suitable. Conclusion Titanium surfaces with directional guidance patterning and zirconia surfaces best supported cell proliferation during the first week of cell culture. Lack of standardization in surface definitions (machined or polished), methodology, and reporting prevented analytical comparison and should be imposed in future studies.

Seeking useful biological agents for mycotoxin detoxification has achieved success in the last twenty years thanks to the participation of many multidisciplinary teams. We have recently witnessed discoveries in the fields of bacterial genetics (inclusive of next-generation sequencing), protein encoding, and bioinformatics that have helped to shape the latest perception of how microorganisms/mycotoxins/environmental factors intertwine and interact, so the road is opened for new breakthroughs. Analysis of literature data related to the biological control of mycotoxins indicates the ability of yeast, bacteria, fungi and enzymes to degrade or adsorb mycotoxins, which increases the safety and quality of susceptible crops, animal feed and, ultimately, food of animal origin (milk, meat and eggs) by preventing the presence of residues. Microbial detoxification (transformation and adsorption) is becoming a trustworthy strategy that leaves no or less toxic compounds and contributes to food security. This review summarizes the data and highlights the importance and prospects of these methods.

Acquired PARP inhibitor (PARPi) resistance in BRCA1- or BRCA2-mutant ovarian cancer often results from secondary mutations that restore expression of functional protein. RAD51C is a less commonly studied ovarian cancer susceptibility gene whose promoter is sometimes methylated in the tumor, leading to homologous recombination deficiency and PARPi sensitivity. For this study, the PARPi-sensitive patient-derived xenograft PH039, which lacks demonstrable repair gene mutations but harbors RAD51C promoter methylation, was selected for PARPi resistance by repeated 21-day niraparib treatments in vivo. PH039 acquired PARPi resistance by the third cycle of treatment and demonstrated unimpeded growth during subsequent exposure to either niraparib or rucaparib. Transcriptional profiling throughout the time course of resistance development showed widespread pathway level changes along with a marked increase in RAD51C mRNA, which reflected loss of RAD51C promoter methylation. Analysis of RAD51C methylation in patient tumor samples from the ARIEL2 Part 1 clinical trial of rucaparib monotherapy likewise indicated that loss of RAD51C methylation prior to on-study biopsy was associated with limited response. Interestingly, the PARPi resistant PH039 model remained platinum sensitive. Collectively, these results not only indicate that PARPi treatment pressure can reverse RAD51C methylation and restore RAD51C expression, but also provide an important model for studying the clinical observation that PARPi and platinum sensitivity are sometimes dissociated.

While loss of BRCA1 promoter methylation has been shown to cause PARP inhibitor (PARPi) resistance in high-grade serous ovarian carcinoma (HGSC), the impacts of RAD51C methylation (meRAD51C) remain unresolved. In this study, three PARPi-responsive HGSC patient-derived xenografts (PDX) with RAD51C gene silencing and homologous recombination deficiency were found to have either homogeneous or heterogeneous patterns of meRAD51C. PDX could lose meRAD51C following PARPi treatment (rucaparib/niraparib), where a single unmethylated RAD51C copy was sufficient to drive PARPi-resistance. Genomic profiling revealed this resistance was acquired independently in two distinct PDX lineages. Furthermore, we describe a patient sample where 1/3 RAD51C gene copies lost methylation following neoadjuvant chemotherapy. We show meRAD51C is a positive predictive biomarker for PARPi response and should be screened for routinely in patients. However, methylation loss in a single gene copy is sufficient to cause PARPi resistance and should be carefully assessed in previously treated patients considering PARPi therapy.

The aim of this study was evaluation of the physico-chemical properties and adhesion of microorganisms on poly(lactic acid) (PLA)-based films loaded with grapevine cane extract (5&ndash, 15 wt%). The films were processed in a compression molding machine and characterized by mechanical, thermal, water vapor barrier and microbiological tests. The best physical-chemical properties for PLA film containing 10 wt% of extract were obtained. The addition of 10 wt% of extract into PLA films led to decrease of tensile strength for 52% and increase in elongation at break for 30%. The water vapor barrier of this film formulation was enhanced for 55%. All films showed thermal stability up to 300 &deg, C. The low release of the active compounds from films negatively influenced their antimicrobial and antifungal activity. Botrytis cinerea growth inhibition onto PLA containing extracts (PLA-E) films was in the range between 15 and 35%. On the other side, PLA/extract films exhibited the antiadhesive properties against Pseudomonas aeruginosa, Pectobacterium carotovorum, Saccharomyces pastorianus, and Listeria monocytogenes, which could imply their potential to be used as sustainable food packaging materials for preventing microbial contamination of food.

While both field experience and laboratory experiments have shown that the efficiency of adsorbed corrosion inhibitor films improves upon exposure of the aqueous solution to a hydrocarbon phase, a credible explanation of these results is lacking. Using a combination of experiments and molecular simulations, this study examines how exposure to oil molecules affects the nature of adsorbed corrosion inhibitor films on metal surfaces. It is found that oil molecules get coadsorbed in the corrosion inhibitor films, making them more hydrophobic, structurally more ordered, and well packed. Corrosion inhibitor molecules with a bulky polar head adsorb in nonplanar, cylinder-like morphologies. Coadsorption of oil molecules changes the morphology of these films to a planar self-assembled monolayer.

Objective The predisposing factors for pericarditis recurrence in the pediatric population have not yet been established. This study aimed to define the risk factors for the unfavorable prognosis of pediatric acute pericarditis. Methods This was a retrospective study that included all patients with acute pericarditis treated from 2011 to 2019 at a tertiary referent pediatric center. Results The study included 72 children. Recurrence was observed in 22.2% patients. Independent risk factors for recurrence were: erythrocyte sedimentation rate ≥ 50 mm/h (p = 0.003, OR 186.3), absence of myocarditis (p = 0.05, OR 15.2), C-reactive protein ≥ 125 mg/L (p = 0.04, OR 1.5), and non-idiopathic etiology pericarditis (p = 0.003, OR 1.3). Corticosteroid treatment in acute pericarditis was associated with a higher recurrence rate than treatment with non-steroid anti-inflammatory therapy (p = 0.04). Furthermore, patients treated with colchicine in the primary recurrence had lower recurrence rate and median number of repeated infections than those treated without colchicine (p = 0.04; p = 0.007, respectively). Conclusion Independent risk factors for recurrence are absence of myocarditis, non-idiopathic etiology pericarditis, C-reactive protein ≥ 125 mg/L, and erythrocyte sedimentation rate ≥ 50 mm/h. Acute pericarditis should be treated with non-steroid anti-inflammatory therapy. A combination of colchicine and non-steroid anti-inflammatory drugs could be recommended as the treatment of choice in recurrent pericarditis.

In this work, Aspergillus niger and Fusarium culmorum cell wall by-products were chosen as microbial sources for chitin and chitosan production. Both polysaccharides were characterized by FTIR and 13C-CPMAS NMR, but GPC analysis was only performed for chitosan. SEM-EDX analysis was performed to fungal chitosan loaded with metal ions. Chitosan extracted from both fungus had low to medium molecular weight (Mw) and degree of deacetylations (DD) ranging from 65.7-83.3%. Fungal chitosan samples were intended to be used for bioremediation applications. For this purpose, two independent absorption experiments regarding pesticide Dimethoate (DM) and heavy metal ions (Al(III), As(III), Cd(II), Cu(II), Mg(II), Mn(II), Pb(II), Zn(II), Fe(II)) in a complex mixture were carried out. An experimental design considering the solution pH, contact time and chitosan physicochemical properties (DD) were performed. The highest percentage of dimethoate pesticide and selected metal ions absorption was obtained with highest DD chitosan, the contact time of 24 h, pH 6 for metals and pH 4 for pesticide, repectively. Molecular dynamics simulation studies allowed to analyze at the molecular level the chitosan-DM interaction. A higher number of h-bonds were identified as the main interactions that stabilize the affinity of the chitosan-DM complexes. Based on our results, we suggest the use of a multipurpose fungal chitosan system for water bioremediation.

The African trypanosome Trypanosoma brucei spp. is a paradigm for antigenic variation, the orchestrated alteration of cell surface molecules to evade host immunity. The parasite elicits robust antibody-mediated immune responses to its variant surface glycoprotein (VSG) coat, but evades immune clearance by repeatedly accessing a large genetic VSG repertoire and ‘switching’ to antigenically distinct VSGs. This persistent immune evasion has been ascribed exclusively to amino-acid variance on the VSG surface presented by a conserved underlying protein architecture. We establish here that this model does not account for the scope of VSG structural and biochemical diversity. The 1.4-A-resolution crystal structure of the variant VSG3 manifests divergence in the tertiary fold and oligomeric state. The structure also reveals an O-linked carbohydrate on the top surface of VSG3. Mass spectrometric analysis indicates that this O-glycosylation site is heterogeneously occupied in VSG3 by zero to three hexose residues and is also present in other VSGs. We demonstrate that this O-glycosylation increases parasite virulence by impairing the generation of protective immunity. These data alter the paradigm of antigenic variation by the African trypanosome, expanding VSG variability beyond amino-acid sequence to include surface post-translational modifications with immunomodulatory impact. Trypanosoma brucei parasites switch their variant surface glycoprotein (VSG) coats to escape immune recognition. The crystal structure of VSG3 reveals that additional modifications, such as O-glycosylation, further expand antigenic variation and potentiate immune evasion.

The common understanding of aqueous CO2 corrosion mechanism considers carbonic acid as an electroactive species. The direct reduction of carbonic acid on a steel surface is believed to be the cause of the higher corrosion rates of mild steel, as compared to that observed in strong-acid solutions with the same pH. However, in-depth quantitative analyses based on comprehensive mechanistic models, developed in recent years, have challenged this idea. In an attempt to provide explicit experimental evidence for the significance of direct reduction of carbonic acid in CO2 corrosion of mild steel, the charge transfer controlled cathodic currents in CO2 saturated solutions were investigated in the present study. The experiments were conducted on three different surfaces: Type 316L stainless steel, pure iron, and API 5L X65 mild steel, in order to examine the possible effect of alloying impurities on the kinetics and the mechanism of cathodic currents. The experimental polarization curves showed that at a constant pH, the charge transfer controlled cathodic currents did not increase with increasing partial pressure of CO2 from 0 bar to 5 bar. This confirmed that the direct carbonic acid reduction was not significant at the conditions covered in the present study, and its sole effect was to buffer the hydrogen ion concentration.

Recent findings have suggested that iron oxide nanoparticles (IONPs) have some exceptional chemical characteristics which make them useful in both experimental physiology and cell biology research. These nanoparticles might be applied as drug delivery systems for anti-cancer and other medications. Also, IONPs might be a valuable part of many novel bioassays in various fundamental medical fields. In recent years, several studies have indicated that IONPs may have certain cytotoxic and genotoxic potential in living systems. During in vitro conditions, IONPs might induce generation of reactive oxygen species and cause oxidative stress in some cell populations. The toxicity of IONPs is not yet fully understood, and additional research is needed to confirm if IONPs have detrimental effects on human health. This short article focuses on the recent developments and trends in the fields of nanomedicine and nanobiology regarding iron oxide nanomaterials and their application in fundamental medical disciplines such as experimental physiology. We discuss our previously published works on structural effects of IONPs and other metallic nanoparticles on cell nucleus in in vitro conditions. We also describe our recent findings regarding the impact of IONPs on certain biophysical properties of subcellular components.

The aim of this study was to evaluate longitudinal changes in drained dialysate cancer antigen 125 (dCA-125) levels and to assess relationships between dCA-125 and dialysis quality, peritoneal membrane transport rates, dialysate glucose load, peritonitis and use of erythropoiesis stimulating agents (ESA), angiotensin-converting-enzyme inhibitors (ACEi) and statins in patients with end-stage renal failure during the first 6 months of peritoneal dialysis (PD) treatment. This prospective study included 20 patients (11 males and 9 females; mean age 62.90±12.69 years) who were followed-up during the first 6 months of PD using conventional low pH glucose-based dialysis fluids. The concentration of dCA-125 was measured in all patients, and the peritoneal equilibration test (PET), peritoneal dialysis treatment adequacy (Kt/V), normalized protein catabolic rate (nPCR), and total, peritoneal and residual clearances of urea and creatinine were calculated. Information on peritonitis occurrence, the use of ESA, ACEi and statins were collected. Data were analyzed by the Mann-Whitney test, Wilcoxon matched pairs test and Spearman’s rank correlation. The concentration of dCA-125 significantly decreased during the follow-up (p=0.016). After 6 months of PD treatment, the concentration of dCA-125 decreased significantly (p=0.016) in all patients. The decrease was present in all patients, but was statistically significant in patients on ACEi therapy (p=0.006) and in patients not using statins (p=0.005) or ESA (p=0.012). No correlation was found between dCA-125 and glucose load, but a statistically significant negative correlation between dCA-125 and the PET for creatinine was observed (p=0.013). These findings challenge the role of dCA-125 in predicting mesothelial cell integrity in PD patients. https://doi.org/10.2298/ABS170324021J Received: March 24, 2017; Revised: May 7, 2017; Accepted: May 9, 2017; Published onlione: June 12, 2017 How to cite this article: Jovanovic NŽ, Trbojevic-Stankovic JB, Nesic DM, Obrenovic RŽ, Boricic NI, Stojimirovic BB. Cancer antigen 125 concentrations in patients on chronic peritoneal dialysis: Relationship with dialysis quality and membrane transport properties. Arch Biol Sci. 2018;70(1):13-20.

The mechanism and the kinetics of mild steel corrosion in deaerated aqueous acetic acid solutions was investigated. The behavior of the steady state voltammograms, obtained at pH 3 to pH 5 and acetic acid concentrations up to 41.5 mM, showed that the direct reduction of undissociated acetic acid is not significant, in contrast to what is commonly reported in the literature. Nevertheless, acetic acid was shown to influence the corrosion process, first by increasing the cathodic limiting current through buffering the hydrogen ion concentration at the metal surface, and second by inhibiting the rates of both anodic and cathodic charge transfer reactions by chemically adsorbing onto the metal surface. Considering these mechanistic observations, a comprehensive mathematical model was developed and verified, using the experimental results. The counterpoising effect of acetic acid on the limiting current and the rate of electrochemical reactions was shown to be able to justify the inconsistent and sometimes contradictory behavior previously reported in the literature. Additionally, increasing the temperature was shown to have a synergistic effect with acetic acid concentration on the observed corrosion rates. This behavior is a result of shifting corrosion currents towards the mass transfer controlled range at elevated temperatures, where acetic acid has a determinant effect.

The kinetics of the iron dissolution reaction was investigated in CO2-saturated acidic sodium chloride solutions. While the effect of CO2 on the iron dissolution reaction during corrosion process has received little attention in the existing literature, the experimental polarization curves obtained in the present study on X65 mild steel suggest that CO2 and/or its related carbonate species are directly involved in the metal dissolution reaction. The presence of CO2 was found to significantly influence the kinetics and the mechanism of the iron dissolution reaction at partial pressures as low as 1 bar. The higher corrosion rates observed in CO2-saturated brines as compared to strong acid solutions at the same pH could possibly be explained by the effect of CO2 on the kinetics of the anodic reaction.

Four different model compounds were synthesized and utilized in this research to relate inhibitor alkyl tail length to changes in the activation energy of the electrochemical process associated wit...

A sensitive method for the precisely and accurate determining the presents of fipronil and its metabolites in chicken meat was developed and validated using a modified quick, easy, cheap, effective, rugged and safe approach coupled with gas chromatography-mass spectrometry analysis. The solvent acetonitrile was used for the extraction of the samples with the salt phases composed of sodium chloride and magnesium sulphate, and then in the second phase used C18 and anhydrous magnesium sulphate. The linearity of the analytical response across the studied range of concentrations (0.005-0.050 mg kg-1) was excellent, obtaining correlation coefficients higher than 0.99. The average recoveries of the pesticide ranged from 75 to 106% for fortification levels of 0.005, 0.01 and 0.05 mg kg-1. The precision values associated with the analytical method, expressed as RSD values, were less than 11.15%. Matrix-matched solutions were also prepared by serially diluting the intermediate solution with blank chicken meat sample extracts containing none of the tested analytes to perform matrix-matched calibration with the same concentrations as in the solvent. The validated method was used to analyse the target compounds in 30 real samples imported from European countries. The present of fipronil-desulfinyl metabolite was confirmed in four samples.

The high mortality (>80%) seen in high-grade serous ovarian cancer (HGSOC) highlights the unmet clinical need for treatments capable of producing long-term sustained responses. The related cancer, ovarian carcinosarcoma (OCS), has even poorer survival rates, which is due in part to being a rare cancer but also because of its unique phenotype. OCS are composed of both epithelial (carcinoma) and mesenchymal (sarcoma) components and molecular analysis has shown that most OCS are monoclonal and are derived from a common progenitor with sarcomatous transformation occurring by a stable epithelial-to-mesenchymal transition (EMT) process involving reprogramming of gene expression. Paclitaxel is an effective microtubule-stabilizing drug that is used in the treatment of HGSOC and OCS, however, resistance to platinum-taxane treatment usually occurs within 2-3 years and earlier in many OCS. We have been investigating the microtubule inhibitors, vinorelbine and eribulin, which each bind to distinct regions of microtubules and have a different mechanism of inhibition compared to paclitaxel. Eribulin has also been shown to reverse EMT, inducing vasculature remodeling and changes to the tumor-immune microenvironment. This dual activity of eribulin provides greater potential for improved efficacy in the clinic. Focusing on platinum resistant/refractory patient-derived xenografts (PDX) of HGSOC and OCS we assessed response to paclitaxel, vinorelbine and eribulin treatment and observed that around 50% of PDX were sensitive (HGSOC 8/13, 8/13 and 4/8 respectively; OCS 3/6 for all treatments). To deliver higher doses of drug to tumors but also limit toxicity, antibody-drug conjugates (ADCs) are being developed. MORAb-202 is an eribulin-anti-folate receptor alpha (FRα) ADC. It has been reported that 80-90% of HGSOC express FRα and in our HGSOC PDX cohort 14/15 (93%) were positive. However, only 1/5 (20%) OCS model showed any FRα and this was restricted to epithelial glandular structures, Citation Format: Cassandra J. Vandenberg, Gwo-Yaw Ho, Ksenija Nesic, Elizabeth M. Swisher, Sean M. Grimmond, Matthew J. Wakefield, Holly E. Barker, David D. Bowtell, Clare L. Scott. Improving efficacy of microtubule inhibitors in the treatment of high-grade serous ovarian cancer and ovarian carcinosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1074.

In this study, a predictive model for the corrosion rate and the polarization response of bare steel in aqueous hydrogen sulfide (H2S) environments based on H2S dissociation and its buffering effect was developed. In this model, the hydrogen ion reduction is the only cathodic reaction. The results confirmed that the increased limiting cathodic current densities and the characteristic “double wave” behavior in the cathodic current of this system could be explained by hydrogen sulfide dissociation in the vicinity of the metal surface. The effect of hydrogen sulfide on the rate of iron dissolution reaction was also taken into account by introducing a reaction sequence involving sulfide intermediates into the calculations, parallel to the acidic iron dissolution reaction. The developed model was shown to be able to reasonably represent the characteristic electrochemical behavior of this system. Furthermore, the predicted corrosion rates are shown to be in good agreement with the available experimental data in the literature over a wide range of conditions.

The failure mechanisms of corrosion inhibitors in highly turbulent flow remain a disputed topic. In the present study, corrosion experiments of X65 pipeline steel were performed with an imidazoline-based corrosion inhibitor using a high-shear turbulent channel flow cell, which included a flow disturbance in the form of a small protrusion. Localized corrosion was observed at the protrusion that could be mitigated with an excess inhibitor concentration. It was found that wall shear stress (up to 5000 Pa) was not the cause of inhibitor failure. The flow acceleration at the leading edge of the protrusion caused a drop in pressure and led to cavitation, with bubble collapse further downstream. This was the main cause of inhibitor failure and localized corrosion. The observed behavior was interpreted in terms of corrosion inhibitor adsorption/desorption kinetics and the associated activation energy analysis.

The objective of this work was to determine the corrosion rate of mild steel and characterize the corrosion products in sour environments at temperatures ranging from 80°C to 200°C. First, a H2S–H2O water chemistry model was developed based on available literature for a closed system at high temperature. Then, H2S corrosion tests were conducted at 80°C, 120°C, 160°C, and 200°C with an exposure time of 4 d. Linear polarization resistance (LPR) and weight loss (WL) methods were used to measure the corrosion rates. X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive x-ray spectroscopy microanalysis (SEM/EDS) were used to characterize the corrosion products and surface morphology. The results show that the initial corrosion rates increased with temperature then decreased as they achieved steady state. The corrosion product was comprised of two distinct layers. The inner corrosion product was always an iron oxide layer (hypothesized to be Fe3O4), while mackinawite, troilite, pyrrhot...

The understanding of sour corrosion mechanisms is an important but still largely elusive target, especially as it pertains to the interaction between corrosion and corrosion product layer formation. The objective of this work was to investigate the effect of high temperature on the corrosion kinetics of carbon steel and the formation of corrosion product layers in sour environments. H2S corrosion experiments were performed at 80°C, 120°C, 160°C, and 200°C with 4 d exposure. Linear polarization resistance was used to determine the corrosion rates. The corrosion products were identified by x-ray diffraction and examined by scanning electron microscopy together with energy dispersive spectroscopy. The results indicate that with the increase of temperature, the initial corrosion rates increased, then reached a steady state over time. Two distinct layers were found in the corrosion products. An inner iron oxide (postulated to be Fe3O4) layer was unexpectedly observed at every studied temperature, while the out...

Localized corrosion has been a challenge for the integrity of mild steel pipelines, specifically at operating conditions where a trace amount of H2S is present alongside CO2 at lower temperatures. The presence of H2S will lead to the formation of a protective iron sulfide layer that will decrease the general corrosion rate; however, a trace amount of H2S may only form a partially protective mackinawite layer that could result in localized corrosion. In the current study, mild steel specimens (API 5L X65) were exposed to a 1 wt% NaCl solution sparged at 0.096 MPa pCO2 and 15 ×10−6 MPa or less pH2S (≤150 ppm H2S/CO2). At pH 5.0 and 30°C the bulk solution was undersaturated with respect to iron sulfide—mackinawite and iron carbonate. At these marginally sour conditions, a H2S/CO2 threshold of approximately 100 ppm was deduced, below which localized corrosion happened. No localized corrosion occurred for the same environmental conditions when H2S/CO2 ratio was above 100 ppm or when there was no H2S present.

A method for directly measuring carbon dioxide (CO2) emissions using a mobile sensor network in cities at fine spatial resolution was developed and tested. First, a compact, mobile system was built using an infrared gas analyzer combined with open-source hardware to control, georeference, and log measurements of CO2 mixing ratios on vehicles (car, bicycles). Second, two measurement campaigns, one in summer and one in winter (heating season) were carried out. Five mobile sensors were deployed within a 1 × 12. 7 km transect across the city of Vancouver, BC, Canada. The sensors were operated for 3.5 h on pre-defined routes to map CO2 mixing ratios at street level, which were then averaged to 100 × 100 m grid cells. The averaged CO2 mixing ratios of all grids in the study area were 417.9 ppm in summer and 442.5 ppm in winter. In both campaigns, mixing ratios were highest in the grid cells of the downtown core and along arterial roads and lowest in parks and well vegetated residential areas. Third, an aerodynamic resistance approach to calculating emissions was used to derive CO2 emissions from the gridded CO2 mixing ratio measurements in conjunction with mixing ratios and fluxes collected from a 28 m tall eddy-covariance tower located within the study area. These measured emissions showed a range of −12 to 226 CO2 ha−1 h−1 in summer and of −14 to 163 kg CO2 ha−1 h−1 in winter, with an average of 35.1 kg CO2 ha−1 h−1 (summer) and 25.9 kg CO2 ha−1 h−1 (winter). Fourth, an independent emissions inventory was developed for the study area using buildings energy simulations from a previous study and routinely available traffic counts. The emissions inventory for the same area averaged to 22.06 kg CO2 ha−1 h−1 (summer) and 28.76 kg CO2 ha−1 h−1 (winter) and was used to compare against the measured emissions from the mobile sensor network. The comparison on a grid-by-grid basis showed linearity between CO2 mixing ratios and the emissions inventory (R2 = 0. 53 in summer and R2 = 0. 47 in winter). Also, 87 % (summer) and 94 % (winter) of measured grid cells show a difference within ±1 order of magnitude, and 49 % (summer) and 69 % (winter) show an error of less than a factor 2. Although associated with considerable errors at the individual grid cell level, the study demonstrates a promising method of using a network of mobile sensors and an aerodynamic resistance approach to rapidly map greenhouse gases at high spatial resolution across cities. The method could be improved by longer measurements and a refined calculation of the aerodynamic resistance.

Naphthenic acids and sulfur compounds present in crude oils may cause corrosion in oil refineries. In some cases, corrosion product scale formed in these oils may provide corrosion protection, but in other cases this may not be true. Current research investigates the nature of protective scales formed on steel corroded by crude oil fractions using microscopic and analytical techniques. This research identifies a thin oxygen-containing layer in-between the steel and a thicker iron sulfide outer layer contributing to the protection against naphthenic acid corrosion. Formation of this oxygen-containing layer is likely due to naphthenic acids in the crude oil.

Localized corrosion in sour fields is a challenge persisting in the oil and gas industry, as it has frequently been seen as a cause for catastrophic failures of upstream pipelines. Hence, ...

Hydrogen sulfide (H2S) corrosion of mild steel is a serious concern in the oil and gas industry. However, H2S corrosion mechanisms, specifically at high partial pressures of H2S (pH2S), have not be...

Different analytical techniques for the detection of mycotoxins have been developed in order to control the levels of mycotoxins in food and feed. Conventional analytical methods for mycotoxin determination are involving techniques such as thinlayer chromatography (TLC), high-performance liquid chromatography (HPLC) and gas chromatography (GC). Also, rapid methods for mycotoxin analysis have become increasingly important. Enzyme-linked immuno-sorbent assay (ELISA) is one of the most common rapid methods for determination of these natural contaminants. The aim of this study was to provide a comparison between two different methods of analysis (HPLC and ELISA) for the detection of different mycotoxins using data that originate from commercial proficiency tests. Based on the statistical evaluation of the results for both methods, in three proficiency tests for various mycotoxins (aflatoxins, ochratoxin and zearalenone), it could be concluded that both techniques can equally be used, although ELISA is considered to be the screening one. У циљу контроле присуства микотоксина и нивоа контаминације хране и хране за животиње развијене су различите аналитичке технике за детекцију ових природних контаминената. Конвенционалне аналитичке методе за утврђивање микотоксина су танкослојна хроматографија (ТЛЦ), течна хроматографија високих перформанси (ХПЛЦ) и гасна хроматографија (ГЦ). Такође, брзе методе за микотоксиколошке анализе постају све важније, међу којима је ЕЛИСА (Enzyme linked immuno-sorbent assay) једна од најприменљивијих. Циљ овог рада био је да се две различите и најчешће коришћене лабораторијске методе за утврђивање различитих микотоксина (ХПЛЦ и ЕЛИСА) упореде анализом података који потичу из комерцијалних тестова оспособљености (proficiency тестова). На основу детаљне статистичке процене резултата добијених применом ових метода за квантификацију афлатоксина, охратоксина и зеараленона, у три комерцијална proficiency теста, може се закључити да обе технике могу равноправно да се користе с великом поузданошћу, иако се често наводи да је ЕЛИСА погодна само за почетну тријажу узорака.

The mechanism of the cathodic reaction in acetic acid corrosion of iron and API X65 mild steel was investigated in mildly acidic sodium chloride electrolytes. The behavior of the charge transfer co...

In the present work, the chemical composition of the Chilean freshwater crab Aegla cholchol exoskeleton was studied for the first time. α-Chitin was isolated from three main body parts (pincers, legs, carapace), and its content ranged from 9.0–10.4% (w/w). Moreover, chitosan was extracted by alkaline treatment at different temperature and time regimes. Aegla cholchol exoskeleton, chitin and chitosans were characterized by FTIR, TGA, and SEM. Chemical structure of chitin and chitosan was confirmed by NMR spectroscopy. Chitosan molecular weight determinations were carried out by GPC. The obtained chitosan samples had a degree of N-acetylation (DA) between 4 and 15% and molecular weight (Mw) in the range of 65–201 kDa. The antifungal activity of the chitosan samples and the chitooligomer were tested toward twenty isolated clinical strains of Candida yeast. Chitosan with lower DA (4%) and higher molecular weight showed the lowest minimum inhibitory concentration (MIC) values, which was evidenced by the highest antifungal activity toward Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis. Results suggest that Aegla cholchol is an excellent natural source for production of bioactive materials with potential applications in the health system, to prevent infections associated with Candida strains.

Background and Objectives: Recurrence of pericarditis (ROP) is an important complication of the acute pericarditis. The aim of this study was to analyse the influence of aetiology, clinical findings and treatment on the outcome of acute pericarditis. Methods: Data were retrospectively collected from medical records of patients treated from 2011 to 2019 at a tertiary referent heart paediatric center. Results: Our investigation included 56 children with idiopathic and viral pericarditis. Relapse was registered in 8/56 patients, 2/29 (7.41%) treated with nonsteroidal anti-inflammatory drugs (NSAID) and 6/27 (28.57%) treated with corticosteroids (CS) and NSAID. Independent risk factors for ROP were viral pericarditis (p = 0.01, OR 31.46), lack of myocardial affection (p = 0.03, OR 29.15), CS use (p = 0.02, OR 29.02) and ESR &ge, 50 mm/h (p = 0.03, OR 25.23). In 4/8 patients the first recurrence was treated with NSAID and colchicine, while treatment of 4/8 patients included CS. Children with ROP treated with CS had higher median number of recurrence (5, IQR: 2&ndash, 15) than those treated with colchicine (0, IQR: 0&ndash, 0.75). Conclusions: Independent risk factors for recurrence are CS treatment, viral aetiology, pericarditis only and ESR &ge, 50 mm/h. Acute pericarditis should be treated with NSAID. Colchicine and NSAID might be recommended in children with the first ROP.

[Image: see text] The integrin αVβ3 receptor has been implicated in several important diseases, but no antagonists are approved for human therapy. One possible limitation of current small-molecule antagonists is their ability to induce a major conformational change in the receptor that induces it to adopt a high-affinity ligand-binding state. In response, we used structural inferences from a pure peptide antagonist to design the small-molecule pure antagonists TDI-4161 and TDI-3761. Both compounds inhibit αVβ3-mediated cell adhesion to αVβ3 ligands, but do not induce the conformational change as judged by antibody binding, electron microscopy, X-ray crystallography, and receptor priming studies. Both compounds demonstrated the favorable property of inhibiting bone resorption in vitro, supporting potential value in treating osteoporosis. Neither, however, had the unfavorable property of the αVβ3 antagonist cilengitide of paradoxically enhancing aortic sprout angiogenesis at concentrations below its IC(50), which correlates with cilengitide’s enhancement of tumor growth in vivo.