Production Levels Research Articles

A study on the performance of corn grain dryer using hybrid solar drying with liquefied petroleum gas

Corn is a widely produced and consumed agricultural product, used as fuel, staple food, and livestock feed. The high level of corn production can lead to potential post-harvest food losses. Drying methods offer a solution to extend the shelf life of a substance. Hybrid solar drying, which combines solar drying with additional heating, particularly using liquefied petroleum gas (LPG), was introduced in this research to ensure faster and more efficient drying processes. The three drying methods compared in this study consist of open sun drying, natural solar drying, and hybrid solar drying. The research results show an average corn grain moisture content of 13.95% over 10.5 hrs, 13.75% over 6 hrs, 13.65% over 7 hrs, 13.45% over 5 hrs, and 13.65% over 4.5 hrs in open sun drying, natural solar drying, and hybrid solar drying with temperature variables of 40°C, 50°C, and 60°C. The average drying rates were 0.212 g/min, 0.364 g/min, 0.318 g/min, 0.439 g/ min, and 0.477 g/min, respectively. The average drying efficiency values for each variable were 2.968%, 4.719%, 5.358%, 5.271%, and 6.037%. In the proximate test, the corn grain moisture content in the hybrid solar drying variable at 60°C was 13.8%, ash was 1.24%, protein was 7.76%, fat was 4.40%, and carbohydrate was 72.8%. For the corn grain color test, the average values obtained were L = 46.48, a = 4.58, and b = 25.37. Meanwhile, the aflatoxin test for dried corn grains showed values of aflatoxin B1, B2, G1, and G2 <0.5 with a total aflatoxin content <2.00. Therefore, hybrid solar drying is recommended over open sun drying and natural solar drying because of its ability to operate even in unfavorable weather conditions, its temperature control capability, its ability to accelerate the drying process, and its capacity to maintain the quality of the material.

Economic and Governance Dimensions of ESG Performance: A Comparative Study in the Developing and European Countries

ABSTRACT: This research delves into the impact of Environmental, Social, and Governance (ESG) metrics on economic practices, focusing on a comparative analysis between developing countries and Europe from 1960 to 2021. It explores how ESG metrics, once peripheral in economic analyses, have become pivotal in shaping economies and societies globally. The study highlights the emerging importance of ESG in understanding economic resilience, societal well-being, and investment priorities, especially in the context of a globalized landscape. Employing a robust mixed-methods approach, the study integrates quantitative and qualitative analyses to examine ESG metrics’ evolving role. Utilizing World Bank data, it encompasses a comprehensive review of 239 regions and nations over a span of six decades. The quantitative component includes descriptive and time series analyses, alongside correlation and regression techniques. Complementing this, a qualitative cultural and economic synthesis provides deeper insight into the data, positioning ESG criteria at the crossroads of financial imperatives, societal obligations, and cultural dynamics. The study uncovers significant correlations between higher Gross Domestic Product (GDP) levels and advanced ESG practices in Europe, indicative of societal values that emphasize sustainability. It reveals varying ESG performances across Western and Eastern European countries compared to developing nations, influenced by distinct cultural economies. The research highlights how regional geopolitical events, cultural norms, and values have shaped diverse trajectories in ESG metrics’ evolution. These findings offer nuanced insights into the complex influences of ESG metrics across different economic, sociopolitical, and cultural landscapes. The study’s outcomes are vital for policymakers and investors, unveiling the intricate nuances and implications of ESG trends. It underscores the need for nuanced policy strategies that consider the unique cultural and economic backgrounds of regions, particularly in developing countries. The research advocates for a cultural-economic perspective in sustainable development, emphasizing the dynamic interplay between society, culture, and economy. The findings suggest that embracing diverse ESG applications can lead to more effective and culturally sensitive approaches to economic development and governance. Conclusively, this research offers a comprehensive cultural-economic perspective on the role of ESG metrics in shaping sustainable development. It serves as a foundational analysis for future studies and policy formulations, aiming to enhance the understanding and application of ESG criteria in diverse economic and cultural settings.

The Palaeo-Productivity Signals Chronicled from the Buxa Formation, North-East Lesser Himalaya, India

ABSTRACT The Mesoproterozoic era is known for its relatively stable ecological conditions and limited atmospheric oxygen. Despite this understanding, uncertainties remain about how ocean chemistry evolved during this time and its potential impact on the development of complex eukaryotic life forms. In response to these uncertainties; we have undertaken a study to investigate indicators of ancient productivity within the Buxa Formation of the Lesser Himalaya in Sikkim. By analyzing the isotopic values ( δ13 C and δ 18Ο values) as well as Rare Earth Element (REE) composition, a total n = 151 carbonate samples were investigated across three sections of the Buxa Formation: Jorethang to Mangalbare, Legship to Naya Bazar, and Reshi to Mangalbare, Sikkim. The study’s findings show that there was minimal variation in δ13C values, consistently ranging between –0.5 and +2.5 ‰ VPDB. This pattern suggests a relatively steady and moderately high level of productivity during that time. This productivity might have been influenced by a temporary increase in atmospheric oxygen levels. Additionally, we have also reviewed and examined stromatolites as part of the investigation.

Engineering EPS in Halomonas bluephagenesis leads to self-flocculation and filamentation for convenient downstream processing

The halophile Halomonas bluephagenesis has established itself as a cost-effective chassis in industrial bioproduction. However, downstream processing (DSP) expense is a persistent challenge. This study uses genetic knockout of exopolysaccharides (EPS-KO) in six industrially relevant H. bluephagenesis strains, each producing distinct polyhydroxyalkanoate (PHA), to evaluate their impact on reducing DSP costs. Remarkably, EPS-KO cells exhibited an unprecedented filamentous morphology, reaching lengths over 50 times (10–75 μm) that of standard cells. This unexpected behavior initially posed a challenge to industrial applicability due to rapid cell lysis under fermentation agitation. Systematic media supplementation of salt, carbon source, nitrogen, and essential minerals significantly influenced morphology, and tailored nutrient schemes that mitigated filamentation while maintaining production levels were designed. Scaled production in a 5000 L bioreactor demonstrated 85 % PHA and 96 g/L cell dry weight after 40 h fermentation, consistent with non-KO cells. During fermentation, EPS-KO enhanced cell-wall penetrability, reducing the need for high-cost γ-butyrolactone by 40 %. Additionally, a new innovative 5000 L FlipFlow bioreactor design cut rotation speed by 50 % and air input by 25 %. During DSP, centrifugation time decreased tenfold due to rapid cell self-flocculation (15–30 min), and the water and enzyme required for PHA purification was reduced by 30 % and 35 %, respectively. This study highlights the use of EPS-KO cells, a controlled media strategy, and low shear force FlipFlow bioreactor to successfully reduce DSP costs without sacrificing productivity. These novel findings represent a notable advancement in cost-saving strategies while presenting the intriguing discovery of media-controlled filamentous cell behavior.

Impacts of circulating cytokine levels and gene polymorphism predisposition on type 1 diabetes mellitus

Purpose: A wide range of cytokines has been demonstrated to be involved in the etiology of type 1 diabetes mellitus (T1DM). Gene polymorphisms may potentially contribute to a hereditary predisposition toward circulating cytokine levels as (high, intermediate, or low) since they can affect cytokine production or function. The aim of this study was to investigate the roles of cytokine levels and the association of single-nucleotide polymorphisms (SNPs) within cytokine genes with T1DM in Saudi children.Methods: Totals of 91 well-characterized T1DM patients and 91 T1DM-free control subjects were enrolled in this study.Results: The levels of 3 circulating cytokines (transforming growth factor [TGF]-β1, interleukin [IL]-10, and IL-6) and 6 SNPs in 3 cytokine genes (TGF-β1 [rs1800470 and rs1800471], IL-10 [rs1800896, rs1800871, and rs1800872], and IL-6 [rs1800795]) that contribute to genetic susceptibility were measured by enzyme-linked immunosorbent assay and polymerase chain reaction with sequence-specific primers. Our fn dings show that TGF-β1 serum levels were signifcantly lower in the children with T1DM than in the control participants. The TGF-β1 genotypes with a high-production phenotype were signifcantly less frequent and those with a lowproduction phenotype were signifcantly more frequent in the children with T1DM compared to the control participants. respectively. Furthermore, the IL-6 genotype frequency with low level of IL-6 production were signifcantly increased in the T1DM group compared to the control group. Moreover, our data demonstrated no appreciable diferences in circulating serum level or genotype and phenotype of IL- 10 between the patients and controls.Conclusion: This kind of measurement, which considers the prediction of T1DM, may be useful in assessing the severity of T1DM and susceptibility to T1DM among Saudi children.

Brain-penetrant complement inhibition mitigates neurodegeneration in an Alzheimer's disease mouse model.

Complement activation is implicated in driving brain inflammation, self-cell damage and progression of injury in Alzheimer's disease and other neurodegenerative diseases. Here, we investigate the impact of brain delivery of a complement-blocking antibody on neurodegeneration in an Alzheimer's mouse model. We engineered a brain-penetrant recombinant antibody targeting the pro-inflammatory membrane attack complex. Systemic administration of this antibody in APPNL-G-F mice reduced brain levels of complement activation products, demonstrating successful brain entry and target engagement. Prolonged treatment decreased synapse loss, amyloid burden and brain inflammatory cytokine levels, concomitant with cognitive improvement compared to controls. These results underscore the potential of brain-penetrant complement-inhibiting drugs as promising therapeutics, targeting downstream of amyloid plaques in Alzheimer's disease.

Assessment of Lead and Iron Concentration in Cosmetics Traded in the AL-Ajilat City Market

This study examined the concentrations of heavy metals, namely lead (Pb) and iron (Fe), in lipsticks, foundations, and face powders to ensure compliance with international safety standards and assess potential health risks. Using atomic absorption spectroscopy (AAS), samples were analyzed for heavy metal content and compared to WHO, FDA, and Health Canada guidelines. Results included that lead levels in lipsticks ranged from 0.03 to 6.15 ppm, with one sample exceeding the WHO limit of 0.01 ppm, raising safety concerns. Iron levels were alarmingly high, with a maximum of 2,566 ppm, well above the WHO guideline of 0.3 ppm. Baseline samples consistently showed low levels of lead at 0.03 ppm, but iron concentrations reached 5,735 ppm, indicating significant safety deviations. Lead concentrations in the face powders ranged from 0.03 to 2.14 ppm, with some exceeding the WHO limit, while iron levels averaged 2,613 ppm, well above acceptable limits. The study concluded that high iron levels in these cosmetic products pose health risks, stressing the need for stricter regulatory oversight and quality control in the cosmetics industry.

Infection Dynamics of Dengue Virus in Caco-2 Cells Depending on Its Differentiation Status.

Dengue virus (DENV), from the Flaviviridae family, is the causative agent of dengue fever and poses a significant global health challenge. The virus primarily affects the vascular system and liver; however, a growing body of evidence suggests its involvement in the gastrointestinal (GI) tract, contributing to clinical symptoms such as abdominal pain, vomiting, and diarrhea. However, the mechanisms underlying DENV infection in the digestive system remain largely unexplored. Prior research has detected viral RNA in the GI tissue of infected animals; however, whether the dengue virus can directly infect human enterocytes remains unclear. In this study, we examine the infectivity of human intestinal cell lines to the dengue virus and their subsequent response. We report that the Caco-2 cell line, a model of human enterocytes, is susceptible to infection and capable of producing viruses. Notably, differentiated Caco-2 cells exhibited a lower infection rate yet a higher level of virus production than their undifferentiated counterparts. These findings suggest that human intestinal cells are a viable target for the dengue virus, potentially elucidating the GI symptoms observed in dengue fever and offering a new perspective on the pathogenetic mechanisms of the virus.

Biofilm-forming bacteria associated with corals secrete melanin with UV-absorption properties.

Corals are colonized by a plethora of microorganisms, and their diversity plays a significant role in the health and resilience of corals when they face oxidative stress leading to bleaching. In the current study, we examined 238 bacteria isolated from five different coral species (Acropora hyacinthus, Pocillopora damicornis, Podabacea crustacea, Porites lobata, and Pavona venosa) collected from the coral reef ecosystems of Kavaratti, Lakshadweep Islands, India. We found that bacteria such as Psychrobacter sp., Halomonas sp., Kushneria sp., Staphylococcus sp., Bacillus sp., Brachybacterium sp., Citrobacter sp., and Salinicola sp. were commonly present in the corals. On the other hand, Qipengyuania sp., Faucicola sp., Marihabitans sp., Azomonas sp., Atlantibacter sp., Cedecea sp., Krasalinikoviella sp., and Aidingimonas sp. were not previously reported from the corals. Among the bacterial isolates, a significant number showed high levels of biofilm formation (118), UV absorption (119), and melanin production (127). Considering these properties, we have identified a combination of seven bacteria from the genera Halomonas sp., Psychrobacter sp., Krasalinikoviella sp., and Micrococcus sp. as a potential probiotic consortium for protecting corals from oxidative stress. Overall, this study provides valuable insights into the coral microbiome and opens up possibilities for microbiome-based interventions to protect these crucial ecosystems in the face of global environmental challenges.

UAMC-3203 inhibits ferroptosis and promotes functional recovery in rats with spinal cord injury.

Spinal cord injury (SCI) results in irreversible neurological impairment. After SCI, Ferritinophagy-induced free iron released from ferritin can lead to extensive lipid peroxidation and aggravate neurological damage. NRF2/HO-1 pathway is to endow cells with a protective effect against oxidative stress, and it plays an important role in the transcriptional activation of a series of antioxidant and detoxification genes. UAMC-3203 is a ferrostatin-1(Fer-1) analogue with better solubility and stability, which can more effectively inhibit ferroptosis after SCI. A rat SCI model was constructed, and the recovery of motor function was observed after treatment with UAMC-3203. ELISA was employed to assess the impact of UAMC-3203 on inflammation-related factors, while immunofluorescence was utilized to investigate the influence of UAMC-3203 on neuronal count as well as the activation of astrocytes and microglia/macrophages. Malondialdehyde (MDA) were detected to reflect the level of oxidation products. Western blot analysis was used to measure the level of ferroptosis markers and the expression of NRF2/HO-1. Our findings demonstrate that UAMC-3203 inhibits the production of reactive oxygen species (ROS) and lipid peroxides, preventing ferroptosis and reducing neuronal degeneration. Additionally, UAMC-3203 suppresses astrocyte proliferation and microglia/macrophage activation, as well as the release of ferroptosis-related inflammatory factors. These combined effects contribute to the preservation of spinal cord tissue and the facilitation of motor function recovery. UAMC-3203 maybe inhibit ferroptosis after SCI to promote functional recovery.

In-situ stabilized lipase in calcium carbonate microparticles for activation in solvent-free transesterification for biodiesel production.

Biodiesel serves as a crucial biofuel alternative to petroleum-based diesel fuels, achieved through enzymatic transesterification of oil substrates. This study aims to investigate stabilized lipase (LP) within calcium carbonate (CaCO3) microparticles as a catalyst for solvent-free transesterification in biodiesel synthesis. The specific hydrolysis activity of the in-situ immobilized LP was 66% of that of free LP. However, the specific transesterification activity of immobilized LP in the solvent-free phase for biodiesel production was 2.29 times higher than that of free LP. These results suggest that the interfacial activation of LP molecules is facilitated by the inorganic CaCO3 environment. The immobilized LP demonstrated higher biodiesel production levels with superior stability compared to free LP, particularly regarding methanol molar ratio and temperature. To the best of our knowledge, there are no previous reports on the in-situ immobilization of LP in a CaCO3 carrier without any crosslinker as an interfacial-activated biocatalyst for biodiesel production.

Pathway-Adapted Biosensor for High-Throughput Screening of O-Methyltransferase and its Application in Vanillin Synthesis.

Vanillin is a widely used flavoring compound in the food, pharmaceutical, and cosmetics area. However, the biosynthesis of vanillin from low-cost shikimic acid is significantly hindered by the low activity of the rate-limiting enzyme, caffeate O-methyltransferase (COMT). To screen COMT variants with improved conversion rates, we designed a biosensing system that is adaptable to the COMT-mediated vanillin synthetic pathway. Through the evolution of aldehyde transcriptional factor YqhC, we obtained a dual-responsive variant, MuYqhC, which positively responds to the product and negatively responds to the substrate, with no response to intermediates. Using the MuYqhC-based vanillin biosensor, we successfully identified a COMT variant, Mu176, that displayed a 7-fold increase in the conversion rate compared to the wild-type COMT. This variant produced 2.38 mM vanillin from 3 mM protocatechuic acid, achieving a conversion rate of 79.33%. The enhanced activity of Mu176 was attributed to an enlarged binding pocket and strengthened substrate interaction. Applying Mu176 to Bacillus subtilis increased the level of vanillin production from shikimic acid by 2.39-fold. Further optimization of the production chassis, increasing the S-adenosylmethionine supply and the precursor concentration, elevated the vanillin titer to 1 mM, marking the highest level of vanillin production from shikimic acid in Bacillus. Our work highlights the significance of the MuYqhC-based biosensing system and the Mu176 variant in vanillin production.

Identification of factors affecting fattening efficiency of commercial pig herds and analysis of their impact at different performance levels.

Improving fattening efficiency is an important goal of breeding commercial pigs, especially for the large-scale pig farms. Fattening efficiency index (FEI) can be used to evaluate the fattening efficiency. The aim of this study was to identify the factors affecting the fattening efficiency of commercial pigs in large-scale pig farms and further study the impact of these factors on the production performance of commercial pig batches at different production levels. The data of 9,570 batches was mainly consisted of four parts (farm facilities, general information of piglets, production performance of nursery pigs and finishing pigs). A total of 28 variables were evaluated by the multi-variable linear regression models. The differences in production factors significantly correlated with FEI at piglets-finishing stage were compared among high-performing (HP), moderate-performing (MP), and low-performing (LP) batches of commercial pigs during the nursery and finishing stage. Among the 28 variables, 18 were significantly correlated with fattening efficiency (P < 0.05), including 11 continuous variables and seven discrete variables. The significant differences among the 11 consecutive variables in the HP, MP, and LP batches of commercial pigs mostly persisted from the piglets-nursery stage to the growing-finishing stage, ultimately affecting the FEI at piglets-finishing stage. For the seven significant discrete variables, the HP batches had a lower proportions in owned source of piglets, number of the purchasing piglets in spring and winter, number of batches in the East and North regions and five-way crossbred pigs, while a higher proportions in the use of closed circuit television video (CCTV) and wastes treatment system. The fattening efficiency of commercial pigs in large-scale pig farms was comprehensively affected by farm facilities, piglets, and production performance at nursery and finishing stage. The low fattening efficiency may have started at the end of nursery stage.

Assessing the effectiveness of financial incentives on electric vehicle adoption in Europe: Multi-period difference-in-difference approach

Electric vehicles (EVs) are considered a promising alternative to achieve a cleaner transportation sector. In the last decade, European countries have implemented financial incentive policies to boost EV adoption. This paper estimates the impacts of these policies on EV adoption in Europe using data from 30 countries from 2012 to 2021 and a multi-period difference-in-differences approach. Our results reveal that purchase incentive policies are associated with increased registrations of battery electric vehicles and plug-in hybrid vehicles, and that the effect holds over time. However, the magnitude and duration of these effects are more significant for battery electric vehicles. Ownership incentive policies do not contribute to EV registrations for either type. Further, the results suggest that policy impacts vary between countries with different levels of gross domestic product per capita and renewable energy consumption. These results contribute to the literature on evaluating financial incentive policies for EV adoption, enabling improved decision making by policymakers.

Effect of Organic Granules on the Productivity, Quality, and Nutrient Uptake Level of Tomato and the Fertility and Microbial Population of the Soil

Effect of Organic Granules on the Productivity, Quality, and Nutrient Uptake Level of Tomato and the Fertility and Microbial Population of the Soil

Geranylgeraniol: Bio-based platform for teprenone, menaquinone-4, and α-tocotrienol synthesis

By utilizing the conformational selectivity of biosynthesis and the flexibility of chemical synthesis, researchers have formulated metabolic engineering-based semi-synthetic approaches that initiate with the final product’s structure and identify key biosynthesis intermediates. Nonetheless, these tailored semi-synthetic routes focused on end-products, neglecting the possibility of biobased intermediates as a platform for derivatization. To address this challenge, this studyproposed a novel strategy resembling chemosynthesis-style divergent exploration to amplify the significance of biobased intermediates, in the case of geranylgeraniol (GGOH). Using the novel bifunctional terpene synthase PTTC066 and systematic metabolic engineering modifications, the engineered yeast straindemonstrated high GGOH production levels (3.32 g/L, 0.039 g/L/h). This platformenabled the semi-synthesis of various pharmaceuticals, including the anti-ulcer drug teprenone, the osteoporosis treatment drug menaquinone-4, and introduced a novel route for synthesizingα-tocotrienol. This study offers a fresh outlook on semi-synthetic approaches, opening avenues for improvements, substitutions, and innovations in industrial production processes.

EFEKTIVITAS VIDEO KESEHATAN TERHADAP PENGETAHUAN DAN SIKAP IBU TENTANG STUNTING DI WILAYAH KERJA PUSKESMAS BANGEKO KANAN

Stunting is a major threat to human quality, as well as a threat to the nation's competitive ability (Ministry of Health, 2018). Because stunting will result in children's intelligence levels not being optimal, making children more vulnerable to disease and in the future could be at risk of decreasing productivity levels. Efforts to prevent stunting should start from the beginning of pregnancy to reduce the risk of stunting in children. The aim of this research is to determine the effectiveness of health videos on mothers' knowledge and attitudes about stunting in the Bangko Kanan Community Health Center Work Area. This research method uses a quasi experimental design. The population used in this research was pregnant women with a sample size of 82 people. The researchers' results were based on the Wilcoxon test with asymp values. The knowledge sig is 0.00 and the attitude is 0.01 (&lt;0.05), meaning that the health video has an impact on increasing mothers' knowledge and attitudes about stunting in the Bangko Kanan Community Health Center working area. It is hoped that the research can become a reference for health workers in providing health promotion to increase knowledge and attitudes of pregnant women about stunting

The Selection of Lettuce Seedlings for Transplanting in a Plant Factory by a Non-Destructive Estimation of Leaf Area and Fresh Weight

Selecting uniform and healthy seedlings is important to ensure that a certain level of production can be reliably achieved in a plant factory. The objectives of this study were to investigate the potential of non-destructive image analysis for predicting the leaf area and shoot fresh weight of lettuce and to determine the feasibility of using a simple image analysis to select robust seedlings that can produce a uniform and dependable yield of lettuce in a plant factory. To vary the range of the leaf area and shoot fresh weight of lettuce seedlings, we applied two- and three-day irrigation intervals during the period of seedling production and calculated the projected canopy size (PCS) from the top-view images of the lettuce seedlings, although there were no significant growth differences between the irrigation regimes. A high correlation was identified between the PCS and shoot fresh weight for the lettuce seedlings during the period of seedling production, with a coefficient of determination exceeding 0.8. Therefore, the lettuce seedlings were classified into four grades (A–D) based on their PCS values calculated at transplanting. In the early stages of cultivation after transplanting, there were differences in the lettuce growth among the four grades; however, at the harvest (28 days after transplanting), there was no significant difference in the lettuce yield between grades A–C, with the exception of grade D. The lettuce seedlings in grades A–C exhibited the anticipated yield (150 g/plant) at the harvest time. In the correlation between the PCS and leaf area or the shoot fresh weight of lettuce during the cultivation period after transplanting and the entire cultivation period, the R2 values were higher than 0.9, confirming that PCS can be used to predict lettuce growth with greater accuracy. In conclusion, we demonstrated that the PCS calculation from the top-view images, a straightforward image analysis technique, can be employed to non-destructively and accurately predict lettuce leaf area and shoot fresh weight, and the seedlings with the potential to yield above a certain level after transplanting can be objectively and accurately selected based on PCS.

Fallopian tube rheology regulates epithelial cell differentiation and function to enhance cilia formation and coordination.

The rheological properties of the extracellular fluid in the female reproductive tract vary spatiotemporally, however, the effect on the behaviour of epithelial cells that line the tract is unexplored. Here, we reveal that epithelial cells respond to the elevated viscosity of culture media by modulating their development and functionality to enhance cilia formation and coordination. Specifically, ciliation increases by 4-fold and cilia beating frequency decreases by 30% when cells are cultured at 100 mPa·s. Further, cilia manifest a coordinated beating pattern that can facilitate the formation of metachronal waves. At the cellular level, viscous loading activates the TRPV4 channel in the epithelial cells to increase intracellular Ca2+, subsequently decreasing the mitochondrial membrane potential level for ATP production to maintain cell viability and function. Our findings provide additional insights into the role of elevated tubal fluid viscosity in promoting ciliation and coordinating their beating-a potential mechanism to facilitate the transport of egg and embryo, suggesting possible therapeutic opportunities for infertility treatment.

Persistent Post COVID-19 Endothelial Dysfunction and Oxidative Stress in Women

The assessment of endothelial dysfunction and free radical homeostasis parameters were performed in 92 women, aged 45 to 69 years, divided into the following groups: women without COVID-19 (unvaccinated, no antibodies, control); women with acute phase of COVID-19 infection (main group, COVID-19+); 12 months post COVID-19+; women with anti-SARS-CoV-2 IgG with no symptoms of COVID-19 in the last 12 months (asymptomatic COVID-19). Compared to the control, patients of the main group had lower glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities, decreased advanced glycation end products (AGEs) level, higher glutathione reductase (GR) activity, and higher glutathione S transferases pi (GSTpi), thiobarbituric acid reactants (TBARs), endothelin (END)-1, and END-2 concentrations (all p ≤ 0.05). The group with asymptomatic COVID-19 had lower 8-OHdG and oxidized glutathione (GSSG) levels, decreased total antioxidant status (TAS), and higher reduced glutathione (GSH) and GSH/GSSG levels (all p ≤ 0.05). In the group COVID-19+, as compared to the group without clinical symptoms, we detected lower GPx and SOD activities, decreased AGEs concentration, a higher TAS, and greater GR activity and GSTpi and TBARs concentrations (all p ≤ 0.05). The high content of lipid peroxidation products 12 months post COVID-19+, despite decrease in ENDs, indicates long-term changes in free radical homeostasis. These data indicate increased levels of lipid peroxidation production contribute, in part, to the development of free radical related pathologies including long-term post COVID syndrome.