Longitudinal waning of mRNA vaccine-induced neutralizing antibodies against SARS-CoV-2 detected by an LFIA rapid test

While mRNA vaccines against SARS-CoV-2 were highly efficacious against severe illness and hospitalization, they seem to be less effective in preventing infection months after vaccination, especially with the Delta variant. Breakthrough infections might be due to higher infectivity of the variants, relaxed protective measures by the general public in “COVID-19 fatigue”, and/or waning immunity post-vaccination. Determining the neutralizing antibody levels in a longitudinal manner may address this issue, but technical complexity of classic assays precludes easy detection and quick answers. We developed a lateral flow immunoassay NeutraXpress™ (commercial name of the test kit by Antagen Diagnostics, Inc.), and tested fingertip blood samples of subjects receiving either Moderna or Pfizer vaccines at various time points. With this device, we confirmed the reported clinical findings that mRNA vaccine-induced neutralizing antibodies quickly wane after 3–6 months. Thus, using rapid tests to monitor neutralizing antibody status could help identify individuals at risk, prevent breakthrough infections and guide social behavior to curtail the spread of COVID-19. Statement of Significance. Mounting evidence suggests that mRNA vaccine-induced neutralizing antibody titres against SARS-CoV-2 wane in 3–6 months. Quick identification of fully vaccinated persons with high risk of breakthrough infections is key to control the COVID-19 pandemic. The described LFIA device having a control/sample dual-lane design serves this purpose with successful field-test data.

Improvement of Texture, Nutritional Qualities, and Consumers’ Perceptions of Sorghum-Based Sourdough Bread Made with Pediococcus pentosaceus and Weissella confusa Strains

Enriched gluten-free products are in high demand owing to increasing celiac disease worldwide. Sourdough fermentation can improve the quality of gluten-free cereals, rendering the resulting product beneficial as a functional food. This study produced sorghum bread (SB) using sourdough technology and evaluated the texture, nutrition profile, bioactive components, and sensory attributes of the product. The base formula was composed of sorghum flour and corn starch. Sourdough made with Pediococcus pentosaceus LD7 (PL7), P. pentosaceus SA8 (PS8), or Weissella confusa SD8 (WS8) was added at a 20% substitution level for bread production, while bread without sourdough addition was used as the control sample. The texture profiles of the SB were significantly (p ˂ 0.05) softer than that of the control. The sourdough breads possessed higher crude protein, ash, and dietary fibre contents than the control bread. Tannin and total phenol contents were significantly (p ˂ 0.05) higher in the sourdough breads compared to the control sample. The specific volume of the sample made with PS8 sourdough was the highest at 2.50 cm3/g compared to the other samples (2.17–2.46 cm3/g). The sourdough samples had higher scores for taste, texture, aroma, and overall acceptability than the control, with PL7 SB exhibiting the best overall acceptability (6.56). This study established promising use of sourdough with starters as an ingredient for baked products with improved technological and nutritional attributes as well as consumer acceptability.

Food Products with High Antioxidant and Antimicrobial Activities and Their Sensory Appreciation

(1) Background: The demand for healthy and nutritious food is growing worldwide. Fermented dairy products are highly valued by consumers for their health benefits. Kefir is a fermented dairy product that brings many benefits to the consumer due to its antioxidant, anticancer, antidiabetic, antihypertensive and antimicrobial properties. Extracts from various plants in the form of volatile oils have a beneficial efct on consumer health. their antioxidant and antimicrobial activities were demonstrated. (2) Methods: In the present study, the main purpose was to obtain a fermented dairy product with a high nutritional value; therefore, kefir, enriched with three types of volatile oils, namely, volatile mint oil, volatile fennel oil and volatile lavender oil, was made. The kefir samples obtained were sensory and texturally analyzed. The beneficial effect on health must also be studied in terms of the acceptability of these products by consumers from a sensory point of view. A non-numerical method based on several multi-personal approval criteria was used to interpret the results obtained in the sensory analysis. In the textural analysis, the consistency, cohesiveness and firmness of the kefir samples were analyzed. (3) Results: The samples enriched with volatile oils obtained superior results compared to the control sample in both conducted examinations. Kefir samples with volatile oils retained their sensory and textural characteristics for a longer time during storage. (4) Conclusions: The volatile oils added to kefir positively influenced the sensory and textural characteristics of the finished product.

Optimization of Gamma Aminobutyric Acid Production Using High Pressure Processing (HPP) by Lactobacillus brevis PML1

In the present research, the production potential of gamma aminobutyric acid (GABA) using Lactobacillus brevis PML1 was investigated. In addition, the microorganism viability was examined in MAN, ROGOSA, and SHARPE (MRS) after undergoing high hydrostatic pressure at 100, 200, and 300 MPa for 5, 10, and 15 min. Response surface methodology (RSM) was applied to optimize the production conditions of GABA as well as the bacteria viability. Analysis of variance (ANOVA) indicated that both the independent variables (pressure and time) significantly influenced the dependent ones (GABA and bacteria viability) ( P < 0.05 ). The optimum extraction conditions to maximize the production of GABA included the pressure of 300 MPa and the time of 15 min. The amount of the compound was quantified using thin-layer chromatography (TLC) and spectrophotometry. For the process optimization, a central composite design (CCD) was created using Design Expert with 5 replications at the center point, whereby the highest content of GABA was obtained to be 397.73 ppm which was confirmed by high performance liquid chromatography (HPLC). Moreover, scanning electron microscopy (SEM) was utilized to observe the morphological changes in the microorganism. The results revealed that not only did have Lactobacillus brevis PML1 the potential for the production of GABA under conventional conditions (control sample) but also the content of this bioactive compound could be elevated by optimizing the production parameters.

Effect of the Cyclic Crack Opening-Closure during Epoxy-Curing Period of a CFRP Strengthening System Bonded on Concrete Substrate

This article investigates the potential detrimental effects of cyclic load during the installation of externally bonded (EB) carbon fiber-reinforced polymer (CFRP) on a damaged reinforced concrete (RC) structure. Four RC specimens were tested in three point bending to study the consequences of crack cyclic opening-closure during epoxy-curing period. A first RC specimen (without bonded CFRP) was loaded monotonically up to failure to serve as undamaged control sample. The three other specimens were pre-cracked before being subjected to a fatigue loading procedure to simulate service condition of a damaged RC structure. Two of the three pre-cracked specimens were strengthened by EB CFRP. One specimen was repaired before the fatigue test while the other one was repaired during the fatigue test. Finally, remaining capacities of all three pre-cracked specimens were measured through monotonic bending tests until failure. It was found that, although bonding of CFRP reinforcement during cyclic load can induce some interesting features with regard to serviceability, cyclic crack opening and closing alters the cure process of epoxy located below the initial crack and decreases the effectiveness of the strengthening at ultimate state. Extended experimental studies are then needed to assess reliable safety factor for the design of repairing operations in which the bridge has to be maintained in service during CFRP installation.

Spicy Plant Raw Materials in Choux Dough

Introduction. Semi-finished choux dough has neither vitamins nor minerals. However, its nutritional value can be increased by adding vegetable raw materials. The research objective was to evaluate the possibilities of using spicy vegetable raw materials in the formulation of semi-finished choux dough. Study objects and methods. The study featured fresh parsley (Petroselinum crispum), basil (Ocimum), celery (Apium) leaves and stems, and IR-dried powder of celery stalks. Standard research methods were used to determine the sensory, physico-chemical, and nutritional properties of the resulting choux samples. Results and discussion. Classical semi-finished choux dough with craquelin served as control sample. Fresh spicy vegetable raw materials degraded the sensory characteristics of the product. However, powdered celery stalks did not interfere with the taste of the choux dough. They were added in the amount of 2.5, 5.0, and 7.5% by weight of wheat flour. The celery powder gave the dough a sour-spicy flavor, as well as increased the content of vitamins B (up to 10%) and beta-carotene (up to 70%) in the finished product. Conclusion. The sample with 5% of IR-dried celery powder proved optimal for choux dough. It increased the content of vitamin B2 and beta-carotene, thus improving the nutritional value of the semi-finished product. In future, the powder can be tested as part of bakery filling in combination with ingredients that mask the typical celery taste.

Effect of Berry Extracts on Saccharomyces cerevisiae Yeast

Introduction. Fruit and berry extracts contain biologically active components and acids that can inhibit or activate Saccharomyces cerevisiae. The research objective was to study the effect of berry extracts on the activity of baking yeast S. cerevisiae and the biochemical properties of wheat dough. Study objects and methods. The experiment featured baking yeast Extra and dry berry extracts of raspberries, aronia, sea buckthorn, and rosehip (LLC Wisterra, Altai Region). The study involved standard and industry-specific control methods of raw materials and semi-finished bakery products, as well as som e standard methods of microbiological analysis. Results and discussion. The raspberry extract (3–4%) suppressed the growth and reproduction of the yeast: after 1 h of exposure, the yeast cell count dropped by 1.5–2 times compared to the control sample. The stimulating effect of the sea buckthorn extract increased the growth rate of yeast cells (up to 40% compared to the control). The extracts of aronia and rosehip had practically no effect on the growth rate of yeast cells. However, 2–3% aronia extract increased the fermentation of the dough, as evidenced by a higher dough fermentation property, which was 2 min versus 3 min at the control after 150 min of exposure. Fruit and berry extracts caused a natural increase in the acidity of the dough, which affected the growth rate of yeast cells. Sea buckthorn extracts increased the acidity so much (up to 4.24 pH units) that it could be regarded as acid stress, which increased the growth rate of yeast cells (1.53×106–1.55×106 vs. 1.10×106 in 1 mL of control sample). The lowest growth rate was detected in the samples with the raspberry extract, which is known to have a strong fungistatic effect: the count of yeast cells decreased by 1.5–2 times after an hour of fermentation. Conclusion. Berry extracts can be of practical interest to bakery enterprises as they help to control yeast fermentation and dough maturation time.

Fermented Milk Beverages Fortified with Soy Protein

Introduction. Fermented milk beverages with various vegetable additives expand the range of functional foods with probiotics, vitamins, and minerals. The research objective was to develop a new technology for fermented milk drinks fortified with soy protein. Study objects and methods. Heat-treated cow’s milk with Direct Vat Set bacterial starter served as the control sample, while the experimental samples featured fermented milk fortified with soy additives. The soy protein ingredient was obtained from powdered sprouted soybean. Soybeans were pre-germinated in a thermostat at 26°C for 24 h and blanched with steam for 15 min. After that, 1–9% of the soy substance was added to pasteurized milk and fermented at 38–40°C for 6–8 h. The resulting sample was tested for quality indicators and physicochemical composition. Results and discussion. The best sensory properties belonged to the sample with 5% mass fraction of the soy additive. As a result, the soy-fortified beverages entitled Bifivit and Immunovit had a better nutritional value: protein – by 1.92 and 1.79 g, fat – by 0.77 and 0.75 g, vitamin E – by 0.16 mg, choline – by 23.82 mg, potassium – by 149 mg, phosphorus – by 19 and 22 mg, calcium – by 25 and 24 mg, magnesium – by 22 and 23 mg, respectively. One portion (100 g) of these drinks contained over 15% of recommended daily intake of protein, vitamin B2, potassium, magnesium, calcium, and phosphorus. The content of lactic acid and bifidobacteria remained above the norm (1×108) both in fresh products and by the end of their shelf life. Conclusion. The article introduces a technology of new functional soy-fortified fermented milk drinks with improved chemical and sensory properties.

Polygenic contribution to the relationship of loneliness and social isolation with schizophrenia

Previous research suggests an association of loneliness and social isolation (LNL-ISO) with schizophrenia. Here, we demonstrate a LNL-ISO polygenic score contribution to schizophrenia risk in an independent case-control sample (N = 3,488). We then subset schizophrenia predisposing variation based on its effect on LNL-ISO. We find that genetic variation with concordant effects in both phenotypes shows significant SNP-based heritability enrichment, higher polygenic contribution in females, and positive covariance with mental disorders such as depression, anxiety, attention-deficit hyperactivity disorder, alcohol dependence, and autism. Conversely, genetic variation with discordant effects only contributes to schizophrenia risk in males and is negatively correlated with those disorders. Mendelian randomization analyses demonstrate a plausible bi-directional causal relationship between LNL-ISO and schizophrenia, with a greater effect of LNL-ISO liability on schizophrenia than vice versa. These results illustrate the genetic footprint of LNL-ISO on schizophrenia.

Two schizophrenia imaging signatures and their associations with cognition, psychopathology, and genetics in the general population

The prevalence and significance of schizophrenia-related phenotypes at the population-level are debated in the literature. Here we assess whether two recently reported neuroanatomical signatures of schizophrenia, signature 1 with widespread reduction of gray matter volume, and signature 2 with increased striatal volume, could be replicated in an independent schizophrenia sample, and investigate whether expression of these signatures can be detected at the population-level and how they relate to cognition, psychosis spectrum symptoms, and schizophrenia genetic risk. This cross-sectional study used an independent schizophrenia-control sample (n=347; age 16-57 years) for replication of imaging signatures, and then examined two independent population-level datasets: Philadelphia Neurodevelopmental Cohort [PNC; n=359 typically developing (TD) and psychosis-spectrum symptoms (PS) youth] and UK Biobank (UKBB; n=836; age 44-50 years) adults. We quantified signature expression using support-vector machine learning, and compared cognition, psychopathology, and polygenic risk between signatures. Two neuroanatomical signatures of schizophrenia were replicated. Signature 1 but not signature 2 was significantly more common in youth with PS than TD youth, whereas signature 2 frequency was similar. In both youth and adults, signature 1 had worse cognitive performance than signature 2. Compared to adults with neither signature, adults expressing signature 1 had elevated schizophrenia polygenic risk scores, but this was not seen for signature 2. We successfully replicate two neuroanatomical signatures of schizophrenia, and describe their prevalence in population-based samples of youth and adults. We further demonstrate distinct relationships of these signatures with psychosis symptoms, cognition, and genetic risk, potentially reflecting underlying neurobiological vulnerability.