Bioprinting and In Vitro Characterization of an Egg White-Based Cardiac Patch for Myocardial Infarction

Myocardial infarction (MI) or heart attack occurs when the bloodstream to the heart is blocked, which may destroy a part of the heart muscle (or myocardium) and form perdurable scarred tissue. The infarcted myocardial muscle nowadays has no revival treatments, and also transplantation is limited as an option. Tissue engineering has the potential to restore myocardial function after an MI by fabricating tailored tissues for treatment. For tissue engineering, three-dimensional (3D) bioprinting is a fabrication method to create 3D constructs with living cells, which would be impossible by other traditional methods. Although various biomaterials, biologically-derived or synthetic, are available, only a few can be used in 3D bioprinting of cardiovascular tissues due to their mechanical weakness of natural biomaterials and/or limited bioactivity (in terms of promoting cell functions) of synthetic ones. The present study aims to develop a novel biomaterial solution for bioprinting (referred to as bioink) and on this basis, to bioprint cell-laden patches and characterize the patches in vitro for potential use in MI treatment. For this, a new bioink was formulated based on chicken egg white (EW) and sodium alginate (Alg). EW, as a rich source of albumin and well-known for its drug delivery applications, has been strategically combined with Alg, a common printable polysaccharide with a non-thrombogenic nature. EW was utilized to improve bioactivity and cell adhesion sites and sodium alginate was considered as an extrudability enhancer to provide good printability. The following research objectives were pursued: I) develop and rheologically characterize the albumin-based bioink by adding minimal amounts of alginate as a printability enhancer biomaterial; II) characterize the mechanical properties of the 3D printed albumin-based patches by compression testing and monitoring the swelling and degradation behavior; and III) characterize the biological properties of the 3D bioprinted cell-laden albumin-based patch by examining the in vitro cell viability. EW-Alg blends with different alginate concentrations were synthesized by mixing the pasteurized egg white with sodium alginate powder. Then the blends were tested in terms of their rheological behavior and showed a non-Newtonian shear-thinning functioning, i.e. the increase of shear strain led to a decline in viscosity. Moreover, the addition of each 0.5 gram alginate in 100 milliliter egg white significantly consolidated the blend's texture and notably changed its viscosity and handling. Hence, the more alginate was used in the solution. Hence, the more alginate was used in the solution, the higher the blend's viscosity and the required extrusion pressure. Compression elastic moduli of the 3D printed patches from the printable EW-Alg blends (2.0, 2.5, and 3.0% Alg in EW) with the range 20-27 kPa showed the similarity of these constructs mostly to human cadaver limb specimens with 10-38 kPa compressive elastic modulus. Furthermore, swelling measurements performed in phosphate-buffered saline (PBS) showed swelling ratios of more than 1800% for all three concentrations of the EW-Alg blend, representing these 3D printed patches' ability to uptaking ionic fluids from a body-like environment. Also, all of the constructs showed signs of biodegradation within a month. The EW-2.0%Alg blend, which had the highest egg white ratio to alginate and the lowest viscosity, was 3D bioprinted as a cell-laden bioink. The loaded human umbilical vein endothelial cells (HUVECs) survival rate was more than 90% in all of the time points within a week, showing high biocompatibility of the EW-Alg bioink. The present study developed an egg white-based bioink for 3D cardiac patch bioprinting. Fabricated patches exhibited suitable mechanical properties and biocompatibility in vitro, to be potentially used for MI treatment

Measuring Landfill Methane Emissions using Satellite and Ground Data

Landfill methane emissions (LME) vary in short periods depending upon the meteorological and atmospheric conditions. In this paper, coupling the Atmospheric InfraRed Sounder (AIRS) with the tracer dilution method (TDM) is proposed during unmeasured emission days to have a better annual estimation of the LME. Some assumptions were made to develop this proposed model. The atmospheric model Advanced Regional Prediction System (ARPS) was employed to evaluate assumptions made during emission estimation using the proposed technique. Methane emissions of a landfill for 13 days during 2011–2013 were measured by the TDM and filtered to remove unreliable data. Then, the filtered data was employed to train the proposed linear regression model to estimate methane emissions. Daytime methane vertical profile concentrations (DMVPC) and nighttime methane vertical profile concentrations (NMVPC) were utilized to study correlations between ground field and satellite measurements for model training. Because field measurements were carried out around noon times, the DMVPC data showed a stronger correlation. Finally, both the TDM interpolation, which is the (normal approach for annual emission estimation) and a coupled of remote sensing (RS) and the TDM technique were utilized to estimate annual LME. The results revealed that interpolating TDM measurements with wide gaps underestimates the LME by about 13% compared to this new RS- field technique, which produces a higher estimation of LME

Rheumatoid Arthritis Flare-ups Following Immunization with Sinopharm Inactivated Virus-based COVID-19 Vaccine

Introduction: This study aimed to investigate the incidence of rheumatoid arthritis (RA) flare-ups following immunization with the Sinopharm COVID-19 inactivated virus-based vaccine. Methods: We conducted a retrospective observational study at the Rheumatology Clinic of Imam Hossein Hospital, incorporating 200 RA patients in remission undergoing non-biologic Disease-Modifying Antirheumatic Drugs (DMARDs) treatments. A rheumatologist confirmed a flare-up based on patients complain of arthralgia and joint stiffness and complete examination of joints over a three-month period following vaccination. Results: Twelve percent of all included patients experienced symptom recurrence. The average age of patients with flare-ups was significantly higher, but no gender-based differences were observed (p<0.001 and p=0.071, respectively). The second vaccine dose resulted in a higher number of symptom flares compared to the first dose (9.30% vs. 3.0%, p < 0.001). No significant differences were observed between patients experiencing flare-ups after the first dose and the second dose in terms of the number of involved joints (p=0.321) and the time gap from vaccination to symptom recurrence (p=0.526). No patients required hospitalization, and prednisolone dosage adjustments effectively managed symptoms. Conclusion: The occurrence of flare-ups was relatively low after the Sinopharm COVID-19 vaccination in RA patients undergoing treatment with DMARDs during remission. The majority of these flares were mild and no hospitalizations were required

Response of vegetables to cadmium-enriched soil

Environmental and water pollution through heavy metals is a growing concern. The recycling of untreated wastewater, which is often contaminated with heavy metals, for agricultural applications is becoming more popular. However, information on the amount of absorption and accumulation of cadmium (Cd) at variable concentrations by different crops is limited. This study aims to analyze the impact of various Cd concentrations (0, 30, 60 and 120 mg/kg) in the root zone on the quantity of its absorption as well as accumulation in various parts of seven different types of common vegetables. The experiments were carried out under laboratory-like controlled conditions. Four treatments and three replicates were selected. Cadmium accumulation exceeded the permissible limits for human consumption, and its accumulation in different plant parts followed this order: Leaves: broccoli > spinach > basil > garlic > carrot > tarragon > dill. Stems: broccoli > spinach > basil > garlic > tarragon > carrot > dill. Roots: broccoli > garlic > basil > spinach > carrot > dill > tarragon. Therefore, the authors recommend the reuse of treated wastewater, which should be virtually free of contaminants such as heavy metals, to irrigate farm lands in the future

Comparative Study of the Long-Term Impact of the COVID-19 Pandemic on Mental Health and Nutritional Practices Among International Elite and Sub-Elite Athletes: A Sample of 1420 Participants from 14 Countries

Background Although several studies have shown that the Coronavirus Disease 2019 (COVID-19) lockdown has had negative impacts on mental health and eating behaviors among the general population and athletes, few studies have examined the long-term effects on elite and sub-elite athletes. The present study aimed to investigate the long-term impact of COVID-19 lockdown on mental health and eating behaviors in elite versus sub-elite athletes two years into the pandemic. A cross-sectional comparative study was conducted between March and April 2022, involving athletes from 14 countries, using a convenient non-probabilistic and snowball sampling method. A total of 1420 athletes (24.5 ± 7.9 years old, 569 elites, 35% women, and 851 sub-elites, 45% women) completed an online survey-based questionnaire. The questionnaire included a sociodemographic survey, information about the COVID-19 pandemic, the Depression, Anxiety and Stress Scale—21 Items (DASS-21) for mental health assessment, and the Rapid Eating Assessment for Participants (REAP-S) for assessing eating behavior. Results The results showed that compared to sub-elite athletes, elite athletes had lower scores on the DASS-21 (p = .001) and its subscales of depression (p = .003), anxiety (p = .007), and stress (p < .001), as well as a lower REAP-S score indicating lower diet quality (p = .013). Conclusion In conclusion, two years into the pandemic, elite athletes were likelier to have better mental health profiles than sub-elite athletes but surprisingly had lower diet quality. Key Points Elite athletes had better mental health profiles compared to sub-elite athletes, with lower levels of depression, anxiety, and stress. Elite athletes reported greater psychological support and perceived themselves as more financially secure during the pandemic than sub-elite athletes do. Elite athletes were more likely to have poor eating habits compared to sub-elite athletes

Comparing the export coefficient approach with the soil and water assessment tool to predict phosphorous pollution : the Kan Watershed case study

Water quality protection has become a key concern in water resources development and management. Uncontrolled nutrient input may challenge the quality of some water bodies. This study uses the relatively steep Kan watershed located in the north-west of Tehran (Iran) as an example case study, where an artificial lake is currently under construction for recreational purposes. Two approaches to predict the total annual phosphorous load were assessed: the soil and water assessment tool (SWAT) and the export coefficient approach. River discharge and sediment transport were simulated prior to modeling of the total phosphorous (TP) load in SWAT to make the model more accurate. In addition, an upstream to downstream calibration method was utilized. Findings reveal that the SWAT-simulated phosphorous load had sound Nash–Sutcliffe efficiency (E NS) values (E NS of 75 % for calibration and E NS of 52 % for validation). The relative error in estimating annual TP load was 7 %. The export coefficient approach assigning coefficients of export for each land use is known as an alternative method that can be used for estimating the TP load. Four sets of export coefficients were selected from the literature to examine their suitability in TP load prediction. The results showed significant errors in TP load prediction, which indicates that export coefficients are likely to be watershed-specific. Likewise, the export coefficients were found to vary through four wet months with errors ranging from 9 % to 33 %. This paper demonstrates that the export coefficient method may estimate the pollution load in the Kan watershed with less data than the advance SWAT model. However, it is associated with a higher level of error

Digestive α-amylase of Bacterocera oleae Gmelin (Diptera: Tephritidae): Biochemical characterization and effect of proteinaceous inhibitor

Digestive α-amylase of Bacterocera oleae larvae was characterized and treated by an inhibitor to gain a better understanding of the degradation of nutritional molecules as a potential target for controlling the pest. Presence of α-amylase was confirmed in the gut of olive fruit fly through the use of a negative control in dinitrosalicylic acid procedure. An optimal pH of 5 was found for amylolytic activity in the gut. The enzyme had optimal activity in a broad range of temperatures 20–45 °C. Among used cations and specific inhibitors, Ca2+, phenylmethylsulphonyl fluoride (PMSF) and ethylene glycol-bis (β-aminoethylether) N,N,N′,N′-tetraacetic acid (EGTA) had statistical differences on amylolytic activity indicating the presence of amino acid triad and Ca2+ in active site of the enzyme. A proteinaceous α-amylase inhibitor was extracted from Polygonum persicaria, a medicinal plant, that widely grows in North of Iran. IC50 value of PPAI was 0.062 mg/ml (i.e. 0.062 mg/ml of extracted inhibitor inhibited 50% of amylolytic activity in the gut of B. oleae larvae) and was temperature and pH dependent. The use of enzyme inhibitors from different plant sources may serve as an important pest control strategy via plant breeding programs. Identification of genes responsible for these inhibitor proteins could be a first step to provide a resistant variety of olive