LB9. Longitudinal antibody dynamics in children infected with SARS-CoV-2 through 6 months post-infection

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection elicits antibodies (Abs) that bind several viral proteins such as the spike entry protein and the abundant nucleocapsid (N) protein. We examined convalescent sera collected through 6 months (~24wks) post-SARS-CoV-2 infection in children to evaluate changes in neutralization potency and N-binding. Methods Outpatient, hospitalized, and community recruited volunteers < 18 years with COVID-19 were enrolled in a longitudinal study at Seattle Children’s Hospital. Analysis includes symptomatic and asymptomatic children with laboratory-confirmed SARS-CoV-2 infection who provided blood samples at approximately 4wks (range: 2-18wks, IQR:4-8wks) and 24 wks (range: 23-35wks, IQR:25-27wks) after diagnosis. We measured neutralizing Ab using an in-house pseudoneutralization assay and anti-N binding Ab using the Abbott Architect assay. Results Of 32 children enrolled between April 2020 and January 2021, 27 had no underlying immunocompromised state and 25 of these 27 children had symptomatic disease. Ten of 27 had a > 2-fold decrease neutralization titers between 4 and 24wks (most were < 10-fold); 12 had < 2-fold change; and 5 had neutralization titers that increased > 2-fold over time (Fig. 1A). All but one of these 27 children had detectable neutralizing activity at 24wks. Anti-N Abs were assessed for 25 children at 4wks and 17 children at 24wks (data pending for 14 samples); all children with paired samples had a > 1.75-fold Abbott index reduction at 24wks, and 5 children had no detectable anti-N Abs by 24wks (Fig. 2A). An additional 5 children with symptomatic disease had complicating immunosuppression or multiple blood transfusions; 2 had decreasing neutralizing titers, 2 increased, and 1 had no change (Fig. 1B). Anti-N Abs were undetectable for one child by 24wks (data pending for 4 samples) (Fig. 2B). No participants received COVID-19 vaccine. Figure 1. Pseusoneutralization titers in children over time. Figure 2. Nucleocapsid-binding antibody titers in children over time. Conclusion We show neutralizing Abs wane to a small degree over 24wks post-SARS-CoV-2 infection and remain detectable in most children. In contrast, anti-N Abs decreased, becoming undetectable in some children by 24wks. These findings add to understanding of the natural history of SARS-CoV-2 immunity in children. * This study was supported by CDC BAA75D301-20-R-67897 Disclosures Jesse Bloom, PhD, Flagship Labs 77 (Consultant)Moderna (Consultant) Janet A. Englund, MD, AstraZeneca (Consultant, Grant/Research Support)GlaxoSmithKline (Research Grant or Support)Meissa Vaccines (Consultant)Pfizer (Research Grant or Support)Sanofi Pasteur (Consultant)Teva Pharmaceuticals (Consultant)

Acidity Reduction of Bio-Oil by Methylic Esterification Reactions

An alternative to fossil fuels is the use of triglyceride biomass for conversion to biofuel by the thermal cracking process, also known as pyrolysis. The liquid phase, called bio-oil, has physicochemical properties like petroleum-derived fuels. One of the undesirable characteristics of bio-oil is the high acidity index, due to the presence of short-chain carboxylic acids in its composition. This feature makes refining and use inviable. The objective of this work was to perform esterification reactions using bio-oil, produced from soybean oil pyrolysis already characterized, in order to reduce its acidity index. Besides that, the esterified bio-oil was submitted to different washing experiments to decrease even more the final acidity. For the esterification reaction 25 g of bio-oil was used at a temperature of 64 °C, using from 0.8 to 2.2% sulfuric acid and 0.5 to 99.5% mass ratio of methyl alcohol and bio-oil. The highest acidity index reduction after 20 min was 81.2%, the esterified bio-oil reduced from 129 to 32.4 mg KOH g-1. Esterification reaction followed by washing and neutralization can decrease even more those values and, the acidity index can reach zero.

Acidity Reduction of Bio-Oil by Methylic Esterification Reactions

An alternative to fossil fuels is the use of triglyceride biomass for conversion to biofuel by the thermal cracking process, also known as pyrolysis. The liquid phase, called bio-oil, has physicochemical properties like petroleum-derived fuels. One of the undesirable characteristics of bio-oil is the high acidity index, due to the presence of short-chain carboxylic acids in its composition. This feature makes refining and use inviable. The objective of this work was to perform esterification reactions using bio-oil, produced from soybean oil pyrolysis already characterized, in order to reduce its acidity index. Besides that, the esterified bio-oil was submitted to different washing experiments to decrease even more the final acidity. For the esterification reaction 25 g of bio-oil was used at a temperature of 64 °C, using from 0.8 to 2.2% sulfuric acid and 0.5 to 99.5% mass ratio of methyl alcohol and bio-oil. The highest acidity index reduction after 20 min was 81.2%, the esterified bio-oil reduced from 129 to 32.4 mg KOH g-1. Esterification reaction followed by washing and neutralization can decrease even more those values and, the acidity index can reach zero.

Body Mass Index Reduction and Selected Cardiometabolic Risk Factors in Obstructive Sleep Apnea: Meta-Analysis

Although clinical studies have been carried out on the effects of weight reduction in sleep apnea patients, no direct link has been shown between weight reduction and changes in cardio-metabolic risk factors. We aimed to analyze changes in the apnea–hypopnea index and selected cardio-metabolic parameters (total cholesterol, triglycerides, glucose, insulin, blood pressure) in relation to the reduction in body mass index in obstructive sleep apnea patients. Medline, Web of Science and Cochrane databases were searched to combine results from individual studies in a single meta-analysis. We identified 333 relevant articles, from which 30 papers were assigned for full-text review, and finally 10 (seven randomized controlled trials and three nonrandomized studies) were included for data analysis. One unit of body mass index reduction was found to significantly influence changes in the apnea–hypopnea index (−2.83/h; 95% CI: −4.24, −1.41), total cholesterol (−0.12 mmol/L; 95% CI: −0.22, −0.01), triglycerides (−0.24 mmol/L; 95% CI: −0.46, −0.02), fasting insulin (−7.3 pmol/L; 95% CI: −11.5, −3.1), systolic (−1.86 mmHg; 95% CI: −3.57, −0.15) and diastolic blood pressure (−2.07 mmHg; 95% CI: −3.79, −0.35). Practical application of lifestyle modification resulting in the reduction of one unit of body mass index gives meaningful changes in selected cardio-metabolic risk factors in obstructive sleep apnea patients.

The effect of the addition of limestone from Khor Eit on soil stabilization of Omdurman.

The present investigation considered the damages arising from the expansive clay type in the presence of water in Omdurman –Sudan.Geographic Information System (GIS), and Remote Sensing techniques were used to map the geotechnical parameters and accurately locate the problematic clay zones.Soil samples recovered from the Bore Holes and Trial Pits in Al muhandessen, Elbustan, Alarda, Bit Almal and Almulazmeen, during the field work carried out in August 2018 were studied using standard Geotechnical Laboratory methods. The liquid limit varies between 50% and 65%.The samples locations were determined using the Global Positioning System (GPS). The thematic mapper 2000Tm was used for mapping the soil properties in Digital format using ERDAS Imaging 8.5 integrated with other software such as Arc Map. Modeling of the problematic soil was carried out also.The results of the geotechnical data show that montomorillonite and Illite are the dominant high expansive clay type with thickness ranging from one to three meters.The limestone collected from Khor Eit North of Port Sudan, was studied chemically and Calcined at 900°C and slaked to get lime. (10 - 20%) of the lime was added to the sample soil with compaction, results in enhancement of the soil properties, reduction of the plasticity index, reduction of clay activity and hence stabilization of the soil.

Optimization of processing parameters to control Maillard browning in ready-to-eat processed potatoes

Relationship among pH, aw and Maillard browning was investigated in processed potatoes ready-to-eat during cooking and sterilization in autoclave to prevent their colors changes. Central composite rotational design was used for optimization of color (L*, a* and b*), browning index and intermediate compounds index. Reduction in the L* value and increase in the a*, b* value and browning index, indicators for Maillard browning of the processed potatoes were mitigated at pH 4.0–5.0 and aw 0.96–1.00 and accelerated at pH less than 3.0 or more than 7.0 and aw less than 0.84. Formation of intermediate compounds was intensified at pH 5.0 and aw 0.99 and mitigated at pH 7.0 and aw 0.84. Adjustment of the pH to 5.0 and keeping aw at to 0.99 were the most effective parameters of to control Maillard browning in processed potatoes ready-to-eat.

Addressing the Public Health Epidemic of Childhood Obesity Using Public Schools as Health Education Learning Laboratories

In our society, childhood obesity has become a pressing health issue. Childhood obesity occurs when children are considerably overweight for their age and height. Body mass index (BMI) is used to measure the percentage of body fat; therefore, the higher the BMI, the more body fat an individual has accompanied by the likelihood that the individual is obese. This research aims to address the factors that cause childhood obesity. A total of 116 journal articles were used for the development of this paper; the articles were analyzed and selected based on the occurrence of the following keywords and phrases: (1) childhood obesity, (2) social cognition theory, (3) telemedicine, and (4) nutrition education. The literature review showed a relationship between childhood obesity and body mass index (reduction, the use of telemedicine, and school food gardens). Using telemedicine video conferencing software and adding food gardens to public school curricula may be a strategy educators and policymakers can use to reduce the rate of childhood obesity.