Production Of High Concentrations Research Articles

Electrochemical Approaches to CO2 Conversion on Copper-Based Catalysts

ConspectusAs one of the essential pathways to carbon neutrality or carbon negativity, the electrochemical reduction of CO2 offers tremendous prospects for platform chemicals and fuel production. Copper (Cu) is currently the only metal material that is able to reduce CO2 to multicarbon (C2+) products. Despite the fact that copper-based materials have been investigated for decades, we still confront numerous challenges on the path to the fundamental understanding and large-scale deployment of copper-based electrocatalysts for CO2 reduction. For fundamental investigations, it remains a variety of open questions about the CO2 reduction mechanisms. The convoluted C–C coupling pathways and product bifurcation processes confuse the design of efficient catalysts. The active sites of copper-based catalysts remain ambiguous due to surface reconstruction. As for theoretical calculations, the construction of electrolyte–electrode models and the investigation of solvation effects are premature for obtaining confident conclusions. In addition, simple and easily scalable techniques for catalyst synthesis still need to be continuously developed.For practical applications, the CO2 electrolyzer with copper-based materials must be operated with high current densities, high Faradaic efficiencies, high energetic efficiencies, high single-pass conversion rates (high product concentration), and long stability. Nevertheless, due to the intricate nature of electrochemical systems, a high-performance copper-based electrocatalyst alone is not sufficient to meet all of the above commercialization requirements. Therefore, reactor design involving mass transfer enhancement calls for more research input. Based on the above background and the urgency of the net-zero goal, we initiated our research on CO2 electrolysis using copper-based materials with an emphasis on active site identification and mass transfer enhancement.This Account describes our contribution to the field of C2+ products formation. We first discuss the synthesis of copper-based materials with a controlled atomic arrangement and valence states based on neural network-accelerated computational simulations. Using the synthesized catalyst, the selectivity of the target product is improved and the energy consumption of CO2 electrolysis is reduced. Then, we describe the efforts to investigate the reaction mechanisms, such as using first-principles calculations at the atomic level, in situ surface-enhanced vibrational spectroscopies at the micrometer level, and electrochemical kinetics studies at the apparent performance level. We also overview our efforts in the field of reaction system engineering, consisting of a vapor-fed CO2 three-compartment flow cell and a large-scale CO2 membrane electrode assembly, which can increase the reaction rates and single-pass yield. Furthermore, we put forward the main technical obstacles that currently need to be surmounted and provide insights into the commercial application of CO2 electrolysis technology.

Comparison of the sources and oxidative potential of PM2.5 during winter time in large cities in China and South Korea

Regional air pollution is rising in Northeast Asia due to increasing energy consumption resulting from a growing population and intensifying industrialization. This study analyzes the sources of air pollution using fine particulate matter (PM2.5) sampling from the atmosphere over Korea and China. We then use this analysis to further investigate the relationship between organic compounds (source tracers) and the oxidative potential of PM2.5. The PM2.5 concentration during winter measured at a measurement stations in Korea showed no significant variation year-to-year. The PM2.5 concentrations measured during winter at a site near Beijing, China were 62.45 μg/m3 in 2018 and 33.07 μg/m3 in 2020. The sources, as determined from PMF, were analyzed at a site in Korea, the sources as secondary nitrate (34.10 %), secondary sulfate (20.20 %), coal combustion (4.01 %), vehicle emission (8.55 %), cooking and biomass burning (18.39 %), dust (8.45 %), and SOA (6.29 %) were identified. At a site in China, secondary nitrate (17.54 %), secondary sulfate (12.03 %), coal combustion (15.53 %), vehicle emission (12.43 %), cooking and biomass burning (9.25 %), dust (26.40 %), secondary organic aerosol (6.82 %) were identified. Our results show secondary organic carbon had a positive association with oxidative potential in Korea while primary organic carbon presented higher correlation with oxidative potential in China. Further, the ECMWF Reanalysis v5 (ERA5) wind field during the high PM2.5 events demonstrated airflow from the west coast of China resulting in high polar organic compounds at the Korean monitoring site. The results further support that aged PM2.5, which contains secondary products, leads to increased oxidative potential. The results presented explain the high concentrations of secondary products and the impact on the biological activities of PM2.5, supporting additional actions to address the impacts of long-range transport of PM2.5.

Metagenomic insights into the changes in the rhizosphere microbial community caused by the root-knot nematode Meloidogyne incognita in tobacco

Root-knot nematode (RKN) disease is a destructive soil disease that affects crop health and causes huge losses in crop production. To explore the relationships between soil environments, rhizobacterial communities, and plant health, rhizosphere bacterial communities were analyzed using metagenomic sequencing in tobacco samples with different grades of RKN disease. The results showed that the community structure and function of the plant rhizosphere were significantly correlated to the RKN disease. RKN density and urease content were key factors affecting the rhizosphere bacterial community. Urease accelerated the catabolism of urea and led to the production of high concentrations of ammonia, which directly suppressed the development of RKNs or by improving the nutritional and growth status of microorganisms that were antagonistic to RKNs. Further experiments showed that the suppression role of ammonia should be attributed to the direct inhibition of NH3. The bacterial members that were positively correlated with RKN density, contained many plant cell wall degrading enzymes, which might destroy plant cell walls and promote the colonization of RKN in tobacco roots. The analysis of metatranscriptome and metabolism demonstrated the role of these cell wall degrading enzymes. This study offers a comprehensive insight into the relationships between RKNs, bacteria, and soil environmental factors and provides new ideas for the biological control of RKNs.

Microbial Electrosynthesis of Acetate Powered by Intermittent Electricity.

Microbial electrosynthesis (MES) of acetate is a process using electrical energy to reduce CO2 to acetic acid in an integrated bioelectrochemical system. MES powered by excess renewable electricity produces carbon-neutral acetate while benefitting from inexpensive but intermittent energy sources. Interruptions in electricity supply also cause energy limitation and starvation of the microbial cells performing MES. Here, we studied the effect of intermittent electricity supply on the performance of hydrogen-mediated MES of acetate. Thermoanaerobacter kivui produced acetic acid for more than 4 months from intermittent electricity supplied in 12 h on-off cycles in a semicontinuously-fed MES system. After current interruptions, hydrogen utilization and acetate synthesis rates were severely diminished. They did not recover to the steady-state rates of continuous MES within the 12 h current-on period under most conditions. Accumulating high product (acetate) concentration exacerbated this effect and prolonged recovery. However, supply of a low background current of 1-5% of the maximum current during "off-times" reduced the impact of current interruptions on subsequent MES performance. This study presents sustained MES at a rate of up to 2 mM h-1 acetate at an average concentration of 60-90 mM by a pure thermophilic microbial culture powered by intermittent electricity. We identified product inhibition of accumulating acetic acid as a key challenge to improving the efficiency of intermittently powered MES.

Influence of alpha linolenic acid on the motility, viability, antioxidant activity and fertility of frozen-thawed New Zealand white rabbit buck semen

Freezing and thawing processes result in production and accumulation of high concentrations of reactive oxygen species that are detrimental to spermatozoal motility and fertility. Therefore, supplementation of exogenous source of antioxidants to freezing diluent is crucial. The aim of the present study was to investigate for the first time whether supplementation of semen diluent with alpha linolenic acid (ALA) can improve motility, viability, membrane integrity, antioxidant status and fertility of post-thaw rabbit spermatozoa. Semen was collected and pooled from fifteen New Zealand white rabbit bucks. Semen samples were diluted with a tris-citrate-glucose (TCG) extender supplemented with ALA (0, 50, 75 and 100 μmol). Then, extended rabbit semen was cooled at 5°C and cryopreserved in liquid nitrogen. After thawing, spermatozoal quality parameters (individual motility %, viability %, osmotic resistance %, and acrosome integrity %), antioxidant activity (SOD, CAT, and GSH activities), lipid peroxidation (malondialdehyde) and fertility (conception and kindling rates) were evaluated. Results revealed that supplementation of rabbit semen extender with 50 μmol ALA significantly (P<0.05) increased spermatozoal characteristics including motility (56.54%), viability (60.01%), acrosome status (72.66%) and membrane integrity (59.13%). The activity of semen antioxidant enzymes (SOD, CAT, and GSH) showed a significant improvement with a marked decrease in lipid peroxidation. Moreover, the conception (73.30%) and kindling (70.00%) rates were significantly (P<0.05) higher in does inseminated with thawed semen treated with 50 μmol ALA in comparison with other concentrations (0, 75 and 100 μmol). In summary, supplementation of rabbit semen extender with 50 μmol ALA improved motility, viability, membrane integrity, acrosome integrity, antioxidant enzymes activity and fertility of post-thaw rabbit spermatozoa. Our findings suggested that higher concentrations of ALA are detrimental to post-thaw characteristics of New Zealand white rabbit buck spermatozoa. To achieve better results, the semen freezing extender should be supplemented with ALA at lower concentrations, especially 50 μmol.

Evaluating crop models to assess rice yield potential in Argentina

Due to the high concentration of the rice production in Asia, the study and comprehension of rice producing chains outside this continent are key to guarantee the global food security. The objectives of this study were to validate the SimulArroz and ORYZA v3 crop simulation models for rice production in Argentina, estimate the yield potential (Yp) for different sowing dates with both models, and estimate how much Argentina can increase rice production in the current agricultural area by reducing the yield gap. Two contrasting rice models (ORYZA v3 and SimulArroz) were used. Besides both are mechanistic models, Simularroz model requires fewer coefficients than ORYZA v3,. which may increase the systematic error. The coefficient of determination between simulated and measured values was at least 0.74 for grain yield and 0.97 for phenology. RMSEn values for phenology ranged from 5.7% to 9.4%. Both models simulated grain yield accurately at high yield levels (>13 ​Mg ​ha−1) with an RMSE <0.5 ​Mg ha-1. The average irrigated rice Yp for subtropical Argentina estimated by the SimulArroz model ranged from 3.8 to 15.6 ​Mg ​ha−1, and from 7.6 to 14.3 ​Mg ​ha−1 in the ORYZA v3. The differences in the Yp between the models were due to different approaches in the calculation of thermal sum and radiation use efficiency. The increase in the rice production in Argentina if the fields close the exploitable gap (80% of the Yp) would be 42% of the current total rice production or 916,091 ​Mg annually.

Valorizing prickly pear cladodes via methane-arrested anaerobic digestion for carboxylic acid production.

To address climate change, liquid biofuels are an essential alternative to fossil fuels, especially for transportation. The carboxylate platform uses methane-arrested anaerobic digestion (MAAD) to ferment biomass to carboxylic acids, which can be chemically converted to liquid fuels via the carboxylate platform. Most biomass sources require expensive pretreatments to remove lignin; however, prickly pear (Opuntia ficus-indica) cladodes have low lignin content and therefore do not require pretreatment. Furthermore, this sugar-rich feedstock is readily digested to high concentrations of carboxylic acids. At various substrate concentrations, batch MAAD of prickly pear cladodes yielded primarily acetic, butyric, and caproic acids. From these batch data, continuum particle distribution modeling (CPDM) simulated four-stage countercurrent digestion. At a non-acid volatile solid (NAVS) concentration of 100 g/Lliq , CPDM predicts a high total acid concentration of 93 g/L and conversion of 0.93 g NAVSdigested /NAVSfed at a volatile solid loading rate of 6g/(Lliq ·d) and liquid retention time of 35 days. Without chemical pretreatment, co-digestion, or in situ product removal, prickly pear produced high yields, biomass conversion, product concentration, and selectivity compared to previously studied lignocellulosic feedstocks.

Laboratory- to Pilot-Scale Fractionation of Lignocellulosic Biomass Using an Acetone Organosolv Process

Acetone organosolv fractionation of beech and birch wood at the lab-scale results in high sugar yields from the (hemi)cellulose and the isolation of a high-purity lignin. In this study, the process is scaled up to validate the technology at the pilot scale using industrial-size beech and birch wood chips and low liquid-to-solid ratios as a next step toward commercialization. Translation of the fractionation process to the pilot-scale showed a similar performance as compared to the lab-scale processing with a good conversion of the wood polymeric pentoses to mostly monomeric sugars and a high delignification. Continuous lignin precipitation by solvent evaporation using the LigniSep process resulted in the formation of nonsticky lignin aggregates with a good filterability. The improved lignin yields and advanced process design as compared to the traditional dilutive lignin precipitation approaches are likely to translate to a better process economy. The pulp washing efficiency and the recovery of (nonprecipitable) lignin from the aqueous hemicellulose stream still need to be improved for an efficient process design. However, the fractionation performance and high product concentrations in the spent liquor provide an excellent start position for improved process design at the commercial scale.

Fluidized Bed Reactor Type : Reactor Design for Biodiesel Production from SoyBean Oil Using MgO Catalyst

Biodiesel is one of the solutions to future energy problems. One of the abundant biodiesel raw materials in Indonesia is soybean. This study aims to optimize the yield of biodiesel made from soybean oil by selecting the reactor design. This research method uses literature study and thermodynamic calculations from the transesterification reaction of soybean oil and methanol using a MgO catalyst to determine which type of reactor optimizes biodiesel yield. The type of reactor that can help optimize the yield of MgO biodiesel catalyst is a fluidized bed reactor type with an exothermic reaction and a negative Hf value. There is a higher product concentration than the reaction concentration in the scene because the rate constant is higher than one (K &gt; 1), i.e. 1.312. The results of this study are expected to provide information in optimizing the yield of biodiesel from soybean oil.

Radiosynthesis and validation of [18 F]fluoroestradiol in a Synthra plus research platform for use in routine clinical practice.

In this practitioner protocol, the optimization of the radiochemical synthesis of [18 F]fluoroestradiol (FES) on the Synthra RNplus research automated platform is described in detail and a quality control (QC) summary of three validation productions is presented. In comparison with published synthesis methods developed on other platforms, the yield was considerably improved (40%-45% ndc). The other important improvement is the reduction of the required concentration of H2 SO4 avoiding the production of high concentrations of acidic vapors that can deteriorate the module. Purification was achieved by solid phase extraction, and the required adaptation of an external heating plate to the module to evaporate the ethanol is also described. The product was obtained with high radiochemical purity and fulfilled all the requirements of current Good Manufacturing Practice (cGMP). The final product is formulated as a sterile, pyrogen-free solution suitable for human injection. To the best of our knowledge, this is the first report of FES production using this type of module.

Electrochemical production of extremely high concentrations of hydrogen peroxide in discontinuous processes

This work reports the development and application of a gas diffusion electrode based on Printex L6 carbon for the production of high concentrations of hydrogen peroxide (H2O2) using a flow-by electrochemical reactor in discontinuous operation mode. With the application of current densities ranging between 75 and 200 mA cm−2, the use of Printex L6 carbon-based GDE generated H2O2 concentrations in the range of 4,000–5,000 mg/L, despite the formation of scavengers. The proposed technique also promoted the production of ozone and persulfate species though at low concentrations. The application of the Printex L6 carbon-based GDE led to a roughly 3.4–3.9-fold increase in H2O2 concentrations ​​compared to Vulcan XC-72R carbon-based GDE which was used for comparison purposes (Vulcan XC-72R carbon is currently-one of the most widely employed carbon materials in electrochemical processes). In addition, the Printex L6 carbon-based GDE exhibited high stability with a lifetime of 36 Ah (7,5 days) of uninterrupted use at 200 mA cm−2. The improvements observed in the Printex L6 carbon-based GDE can be attributed to the presence of higher amounts of carboxyl oxygenated functional groups in the material and its greater electrochemically active surface area compared to the Vulcan XC-72R-based GDE.

Tissue Engineering and Photodynamic Therapy: A New Frontier of Science for Clinical Application -An Up-To-Date Review.

Tissue engineering (TE) connects principles of life sciences and engineering to develop biomaterials as alternatives to biological systems and substitutes that can improve and restore tissue function. The principle of TE is the incorporation of cells through a 3D matrix support (scaffold) or using scaffold-free organoid cultures to reproduce the 3D structure. In addition, 3D models developed can be used for different purposes, from studies mimicking healthy tissues and organs as well as to simulate and study different pathologies. Photodynamic therapy (PDT) is a non-invasive therapeutic modality when compared to conventional therapies. Therefore, PDT has great acceptance among patients and proves to be quite efficient due to its selectivity, versatility and therapeutic simplicity. The PDT mechanism consists of the use of three components: a molecule with higher molar extinction coefficient at UV-visible spectra denominated photosensitizer (PS), a monochromatic light source (LASER or LED) and molecular oxygen present in the microenvironment. The association of these components leads to a series of photoreactions and production of ultra-reactive singlet oxygen and reactive oxygen species (ROS). These species in contact with the pathogenic cell, leads to its target death based on necrotic and apoptosis ways. The initial objective of PDT is the production of high concentrations of ROS in order to provoke cellular damage by necrosis or apoptosis. However, recent studies have shown that by decreasing the energy density and consequently reducing the production of ROS, it enabled a specific cell response to photostimulation, tissues and/or organs. Thus, in the present review we highlight the main 3D models involved in TE and PS most used in PDT, as well as the applications, future perspectives and limitations that accompany the techniques aimed at clinical use.

Immobilization of Lathyrus cicera Amine Oxidase on Magnetic Microparticles for Biocatalytic Applications.

Amine oxidases are enzymes belonging to the class of oxidoreductases that are widespread, from bacteria to humans. The amine oxidase from Lathyrus cicera has recently appeared in the landscape of biocatalysis, showing good potential in the green synthesis of aldehydes. This enzyme catalyzes the oxidative deamination of a wide range of primary amines into the corresponding aldehydes but its use as a biocatalyst is challenging due to the possible inactivation that might occur at high product concentrations. Here, we show that the enzyme’s performance can be greatly improved by immobilization on solid supports. The best results are achieved using amino-functionalized magnetic microparticles: the immobilized enzyme retains its activity, greatly improves its thermostability (4 h at 75 °C), and can be recycled up to 8 times with a set of aromatic ethylamines. After the last reaction cycle, the overall conversion is about 90% for all tested substrates, with an aldehyde production ranging between 100 and 270 mg depending on the substrate used. As a proof concept, one of the aldehydes thus produced was successfully used for the biomimetic synthesis of a non-natural benzylisoquinoline alkaloid.

DETERMINATION OF THE ECOLOGICAL CONDITION OF THE ATMOSPHERIC AIR IN THE RAKIVKA MICRODISTRICT OF KREMENCHUK

Due to the transformation of the environment under anthropogenic influence, the most acute problem was the monitoring of the ecological state of the environment, the essence of which is the system of observations of changes in the state of the environment and forecasts made on the basis of these observations. Due to the high concentration of population and production, the urban environment is exposed to various environmental impacts that have a negative impact on biotic groups. The impact on living organisms of cities is due to various types of pollution of the atmosphere, water and soil. The degree of air pollution can be determined by various methods, one of which is bioindication. The main advantage of this approach is that the quality of the environment is assessed by the condition of those objects that are directly and permanently in the environment. The aim of the study was to determine the ecological status of the air in the Rakivka district of Kremenchuk by the method of bioindication and to develop ways to improve its quality.

Thermal characterization of straight and curve edge blade liquid fuel swirl burner

Accurate monitoring and controlling of the temperature in the combustion chamber can raise the burner efficiency, combustion intensity, fuel consumption and reduce pollutant emission. However, except combustion is accurately monitored and controlled, high concentration of pollutant gases and products like carbon monoxide (CO) and soot can form in the combustion chamber. This paper compares the combustion thermal profiles in a liquid fuel swirl burner using developed straight edge and curve edge blade swirlers at (20, 30, 40, 50 and 60)° for 6, 8, 10 and 12 number of blades in order to optimize the temperature of the burner. Measurements were made in straight and curve blades liquid fuel swirl burner in order to study and compare the thermal characteristics of the straight and curve edge blades in optimizing the combustion dynamics. Similarly, measurements were made for burner without swirl generator and the combustion temperature assessed. Thermal profile was measured in the direction of flow via the six axial ports at distance ((d) =150, 350, 550, 750, 950 and 1150 mm) from the burner exit using Chromium-Zinc thermocouple. Results showed that the wavelength and oscillation of temperature decay in the same type of blade followed the same trend and the peak of combustion intensity is nearer the nozzle for curve edge blades than the straight edge blade. Six (6) blades performed best with the highest temperature in all the ports, while 12 blades gave the least performance. Findings further show that curve edge blade swirlers gave better performance than straight edge blade swirlers with highest temperature of (1065 and 1015) °C, respectively. Hence, it is recommended especially where high temperature and stability application is desirable

Enhanced hydrogen production from water hyacinth by a combination of ultrasonic-assisted alkaline pretreatment, dark fermentation, and microbial electrolysis cell

In this study, hydrogen (H2) production from water hyacinth (WH) was enhanced by the integration of the ultrasonic-assisted alkaline (UAA) pretreatment, dark fermentation (DF), and microbial electrolysis cell (MEC). The results showed that UAA pretreatment improved around 350% in H2 production in the DF stage and nearly 400% in the whole process compared to un-pretreated. The H2 yield in the DF stage reached the maximum value of 110.4 mL/g-VS at a WH concentration of 20 g-TS/L. However, high concentrations of co-produced soluble metabolite products (SMPs) and suspended solid in DF effluent adversely affected the efficiency of the MEC stage. Consequently, a WH concentration of 5 g-TS/L was optimal for the UAA-DF-MEC process that achieved the highest H2 yield of 565.8 mL/g-VS. It suggests that other auxiliary processes (e.g., dilution, centrifugation, effective methanogen inhibition, etc.) need to be developed to further improve the H2 production from WH via the UAA-DF-MEC process.

MO714: PARK7—A Novel Therapeutic Target for Peritoneal Dialysis Induced Peritoneal Membrane and Vascular Transformation

Abstract BACKGROUND AND AIMS Patients with chronic kidney disease (CKD) suffer from increased oxidative stress, which is further aggravated in patients on peritoneal dialysis (PD). Parkinson disease protein 7 (PARK7) has antioxidant and antiapoptotic activity; its role in PD is unknown. METHOD Transcriptome and proteome data sets from microdissected omental arterioles obtained from age-matched non-CKD children, children with CKD5 and children on PD with fluids containing low or high concentrations of glucose degradation products (GDP; n = 6/group) underwent PARK7 related gene set analysis (FDR &amp;lt; 0.05). Respective parietal peritoneal tissues (n = 60) underwent digital histomorphometry analyses. PARK7 western blotting was performed in effluents of eight children on high-GDP PD. Human umbilical endothelial cells (HUVEC) viability (MTT assay) and transepithelial electrical resistance (TER, Transwells) and 4-, 10- and 70-kDa dextran transport were measured (n = 6–12/group). As an extreme phenotype approach of PD toxicity, C57/BL6J mice were treated with chlorhexidine digluconate (CG) and PARK7 activator for 7 days and parietal peritoneal damage was quantitated (n = 6–8/group). RESULTS Arteriolar transcriptome analyses in children on low-GDP PD demonstrated the enrichment of PARK7 related GO terms of oxidant detoxification as compared to CKD5 and in children on high-GDP PD that of reactive oxygen species-, mitochondria- and apoptosis-related processes. On the proteome level the DNA repair/organization, catabolic and mitochondria associated processes were enriched in children on low-GDP PD, and mitochondrial processes in children on high-GDP PD. PARK7 was detected in the parietal peritoneal tissues in mesothelial, endothelial and inflammatory cells, in myocytes and fibroblasts and was present in the PD effluents. Total peritoneal and submesothelial PARK7 abundance was similar in controls, patients with CKD5 and in patients on low-GDP PD, but 2-fold increased in patients on high GDP PD compared to controls and CKD5. Mesothelial PARK7 was 2-fold increased in children on low-GDP PD versus CKD5, endothelial PARK7 abundance was similar in all four groups. In low-GDP PD patients endothelial PARK7 abundance correlated with vessel lumen/vessel diameter ratio (r = 0.53, P = 0.06), i.e. inversely with lumen obliteration. Submesothelial PARK7 correlated with microvessel density (r = 0.55, P = 0.05), with submesothelial hypoxia inducible factor-1 and angiopoietin-1 and -2 (ρ = 0.63, P = 0.023; r = 0.91, P &amp;lt; 0.0001; r = 0.60, P = 0.03) but not with VEGF. Submesothelial and endothelial PARK7 correlated with respective caspase 3 abundances (r = 0.74/0.68, P = 0.009/0.015). In HUVEC methylglyoxal (MG) dose- and time-dependently reduced viability, coincubation with PARK7 activator partially preserved endothelial cell viability. In Transwells, MG treatment decreased TER and increased dextran transport, but none of them was improved by PARK7 activation. In mice treated with CG submesothelial thickness was 2-fold increased, microvessel density was unchanged; PARK7 protein abundance was 5-fold reduced. Co-treatment of CG with PARK7 activator prevented the submesothelial thickening. CONCLUSION PD modifies arteriolar PARK7 related biological processes of oxidant detoxification, mitochondria- and apoptosis-related processes. PARK7 is ubiquitously expressed in the parietal peritoneum and regulated by the GDP content of PD fluids. In patients on low-GDP PD, PARK7 abundance correlated with the degree of arteriolar lumen narrowing, and VEGF-independent angiogenesis. Activation of PARK7 preserves endothelial cell viability in vitro and prevents CG induced peritoneal membrane damage in mice and thus represents a potential novel therapeutic approach.

Characteristics of metabolic disorders in laying hens with dermanyssosis

Dermanyssosis is a common ectoparasitic disease of birds. Some characteristics of metabolic disorders were identified in Hy-Line laying hens with such a disease. The disease caused by Dermanyssus gallinae, a poultry red mite, was detected during a complex parasitological survey in one of two industrial poultry buildings inspected. A high degree of mite infestation was found in the poultry building where the hens of the experimental group were kept. This condition was considered to be a stress factor for the hens, i.e. as a disturbance of their comfortable living conditions. The D. gallinae parasite infestation caused a decrease in erythrocytes and leukocytes, and in hemoglobin concentration in the laying hens. Changes in the content of some stress-associated hormones were analyzed, and they showed an increase in cortisol levels and a decrease in triiodothyronine. Multiple metabolic rate disorders in the organism of the infested hens were revealed. In dermanyssosis stimulation of gluconeogenesis occurred and an increase in the proportion of oxygen-free glycolysis in the hens. These changes were obviously due to the molecular effects of the increase in stress. The hens from the experimental group were found to have high concentrations of lipid peroxidation products as compared to the control. Increased lipid peroxidation was found, together with a decrease in the total antioxidant defense of the experimental laying hens’ organisms. The research results add to our understanding of how a high degree of infestation of a poultry building by D. gallinae impacts the organism of Hy-Line hens.

Assessment of iron metabolism disorders and adequate treatment of anemic syndrome in patients with breast cancer on the background of adjuvant chemotherapy

Early and adequate correction of the anemic syndrome (AS) of cancer patients can prevent deterioration in the quality of life and be considered as a reserve for increasing the effectiveness of treatment for breast cancer (BC). The aim of the study was to assess the status of iron using modern methods of ferrokinetics in breast cancer patients on the background of adjuvant chemotherapy for early diagnosis and adequate treatment of AS. The object of the study included 21 breast cancer patients with a relatively favorable prognosis, with luminal types A and B (Her 2 / neu positive or negative), three times negative type. The examination was carried out in the postoperative period, against the background of adjuvant chemotherapy. The main metabolites of ferrokinetics were studied: hepcidin 25 (GP25); ferritin (FR); soluble transferrin receptors (rRTP); transferin (TRF); iron (Fe); erythropoietin (EPO); CRP and IL-6 indicators. AC correction was performed (ferinject, epotin-alpha, B12). 10 (47.6%) patients with breast cancer had AS. Most of them were diagnosed with IDA with microcytic, hypochromic characteristics of erythrocytes, low concentration of FR, Fe, GP25, IL-6, CRP, and high levels of TRP and rRTP. Functional iron deficiency (FDF) was established in some patients. In contrast to patients with IDA, they had a high concentration of FR, CRP and significant production of GP25, IL-6. The EPO level was not optimal for the majority of patients with AS. In isolated cases, during treatment with recombinant erythropoietins, a deficiency of vitamin B12 (cyanocobalamin) was revealed. The rational use of iron preparations, vitamins, and recombinant forms of EPO made it possible to restore Fe metabolism, stabilize the hemoglobin level, and also improve the condition of most breast cancer patients. The obtained data on IL-6, GP25, CRP indicate a certain relationship between them in the development of anemia with VDF in breast cancer patients and the need for further study of the characteristics of iron metabolism in cancer patients.

Kinetic Studies of the Activation of Bordetella pertussis Adenylate Cyclase by Calmodulin.

Adenylate cyclase toxin (ACT) is a virulence factor secreted by Bordetella pertussis and plays a causative role in whooping cough. After ACT attaches to lung phagocytes, the adenylate cyclase (AC) domain of the toxin is transported into the cytoplasm where it is activated by calmodulin (CaM) to cyclize ATP into 3',5'-cyclic adenosine monophosphate (cAMP). Production of high concentrations of cAMP disrupts immune functions of phagocytes. To better understand the mechanism of activation of AC by CaM, the studies reported herein were conducted. Major observations are as follows: (1) dependence of steady-state velocities on CaM and ATP concentrations suggests that CaM and ATP bind to AC in a random fashion. (2) A pre-steady-state lag phase is observed when AC is added to solutions of CaM and ATP, reflecting the association of AC and CaM. Analysis of pre-steady-state data indicates that CaM binds to AC and AC:ATP with second-order rate constants of 30 and 60 μM-1 s-1, respectively, and that CaM dissociates from the resultant complexes with a first-order rate constant of 0.002 s-1. (3) A biphasic dependence of steady-state velocities on CaM concentration is observed: the first phase extending from 0.01 to 1 nM CaM (Kd,obs ∼ 0.06 nM) and the second phase from 1 to 2000 nM CaM (Kd,obs ∼ 60 nM). These results suggest that AC exists in at least two conformations, with each conformation exhibiting distinct binding affinity for CaM and distinct potential for activation.