Global patterns of antigen receptor repertoire disruption across adaptive immune compartments in COVID-19.

Whereas pathogen-specific T and B cells are a primary focus of interest during infectious disease, we have used COVID-19 to ask whether their emergence comes at a cost of broader B cell and T cell repertoire disruption. We applied a genomic DNA-based approach to concurrently study the immunoglobulin-heavy (IGH) and T cell receptor (TCR) ß and δ chain loci of 95 individuals. Our approach detected anticipated repertoire focusing for the IGH repertoire, including expansions of clusters of related sequences temporally aligned with SARS-CoV-2-specific seroconversion, and enrichment of some shared SARS-CoV-2-associated sequences. No significant age-related or disease severity-related deficiencies were noted for the IGH repertoire. By contrast, whereas focusing occurred at the TCRß and TCRδ loci, including some TCRß sequence-sharing, disruptive repertoire narrowing was almost entirely limited to many patients aged older than 50 y. By temporarily reducing T cell diversity and by risking expansions of nonbeneficial T cells, these traits may constitute an age-related risk factor for COVID-19, including a vulnerability to new variants for which T cells may provide key protection.

Dual effects of supplemental oxygen on pulmonary infection, inflammatory lung injury, and neuromodulation in aging and COVID-19.

Clinical studies have shown a significant positive correlation between age and the likelihood of being infected with SARS-CoV-2. This increased susceptibility is positively correlated with chronic inflammation and compromised neurocognitive functions. Postmortem analyses suggest that acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), with systemic and lung hyperinflammation, can cause significant morbidity and mortality in COVID-19 patients. Supraphysiological supplemental oxygen, also known as hyperoxia, is commonly used to treat decreased blood oxygen saturation in COVID-19 patients. However, prolonged exposure to hyperoxia alone can cause oxygen toxicity, due to an excessive increase in the levels of reactive oxygen species (ROS), which can overwhelm the cellular antioxidant capacity. Subsequently, this causes oxidative cellular damage and increased levels of aging biomarkers, such as telomere shortening and inflammaging. The oxidative stress in the lungs and brain can compromise innate immunity, resulting in an increased susceptibility to secondary lung infections, impaired neurocognitive functions, and dysregulated hyperinflammation, which can lead to ALI/ARDS, and even death. Studies indicate that lung inflammation is regulated by the central nervous system, notably, the cholinergic anti-inflammatory pathway (CAIP), which is innervated by the vagus nerve and α7 nicotinic acetylcholine receptors (α7nAChRs) on lung cells, particularly lung macrophages. The activation of α7nAChRs attenuates oxygen toxicity in the lungs and improves clinical outcomes by restoring hyperoxia-compromised innate immunity. Mechanistically, α7nAChR agonist (e.g., GAT 107 and GTS-21) can regulate redox signaling by 1) activating Nrf2, a master regulator of the antioxidant response and a cytoprotective defense system, which can decrease cellular damage caused by ROS and 2) inhibiting the activation of the NF-κB-mediated inflammatory response. Notably, GTS-21 has been shown to be safe and it improves neurocognitive functions in humans. Therefore, targeting the α7nAChR may represent a viable therapeutic approach for attenuating dysregulated hyperinflammation-mediated ARDS and sepsis in COVID-19 patients receiving prolonged oxygen therapy.

PGC-1α overexpression is not sufficient to mitigate cancer cachexia in either male or female mice.

Cancer cachexia (CC) accounts for 20%-40% of cancer-related deaths. Mitochondrial aberrations have been shown to precede muscle atrophy in different atrophy models, including cancer. Therefore, this study investigated potential protection from the cachectic phenotype through overexpression of peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α). First, to establish potential of mitochondria-based approaches we showed that the mitochondrial antioxidant MitoTEMPO (MitoT) attenuates myotube atrophy induced by Lewis lung carcinoma (LLC) cell conditioned media. Next, cachexia was induced in muscle-specific PGC-1α overexpressing (MCK-PCG1α) or wildtype (WT) littermate mice by LLC implantation. MCK-PCG1α did not protect LLC-induced muscle mass loss. In plantaris, Atrogin mRNA content was 6.2-fold and ∼11-fold greater in WT-LLC vs WT-phosphate-buffered saline (PBS) for males and females, respectively (p < 0.05). MitoTimer red:green ratio for male PGC was ∼65% higher than WT groups (p < 0.05), with ∼3-fold more red puncta in LLC than PBS (p < 0.05). Red:green ratio was ∼56% lower in females WT-LLC vs PGC-LLC (p < 0.05). In females, no change in red puncta was noted across conditions. Lc3 mRNA content was ∼73% and 2-fold higher in male and female LLC mice, respectively, vs PBS (p < 0.05). While MitoT could mitigate cancer-induced atrophy in vitro, PGC-1α overexpression was insufficient to protect muscle mass and mitochondrial health in vivo despite mitigation of cachexia-associated signaling pathways.

Identity mediates inequity and flourishing among racially minoritized and international undergraduate college students.

OBJECTIVE: Racially minoritized individuals can simultaneously experience both oppression and flourishing (ie, positive mental health). This study examines identity connection as a mediator of this relationship. PARTICIPANTS: Undergraduates at a large, private university (n = 771), 59.4% racially minoritized American or international (RMA/I). METHODS: Measures included perception of value, perception of fair/equitable treatment, identity centrality (ie, significance of racial/ethnic identity), identity exploration, and flourishing. Structural equation models compared RMA/I vs. white American students. RESULTS: Among RMA/I students, flourishing was predicted by perception of value and identity centrality; identity centrality was positively predicted by perception of value and negatively predicted by perception of fair/equitable treatment. Among white American students, only perception of value predicted flourishing. CONCLUSIONS: Identity centrality mediated the relationship between fair/equitable treatment and flourishing among these minoritized undergraduate students, supporting theory that identity may be formed in response to oppression.

A qualitative examination of the impacts of financial stress on college students' well-being: Insights from a large, private institution.

OBJECTIVE: This qualitative research aims to provide deeper insight into college students' experiences by examining the impact of financial stress on their well-being. METHODS: Four focus groups were conducted at a large, private, urban university in the United States over the course of 1 month, each lasting approximately 1 h. Facilitators used a structured moderator guide to maintain consistency. Four focus groups were conducted and a total of 30 students participated. Students were primarily Asian (66.7%) and White (30.0%), and a majority were female (86.7%). Student participants were 43.3% undergraduate and 56.6% graduate. Transcripts were analyzed in Atlas.ti 8 software using line-by-line open coding guided by the principles of qualitative content analysis. An inductive approach was utilized to code the data. Emergent categories and concepts were then organized hierarchically into themes and subthemes. RESULTS: Two overarching themes emerged from the focus group analysis. In these students' perspectives, financial stress impedes their ability to succeed academically. Another major theme is the impact of finances on students' social lives. Students experiencing financial stress find it challenging to navigate relationships with wealthier peers, often leading to feelings of isolation and embarrassment. CONCLUSION: Given the reported negative impact on students' well-being, further research is needed to determine methods for mitigating financial stress.

Author Correction: A dynamic COVID-19 immune signature includes associations with poor prognosis.

A Correction to this paper has been published: https://doi.org/10.1038/s41591-020-01186-5.

A Cross-Sectional Study Examining the Seroprevalence of Severe Acute Respiratory Syndrome Coronavirus 2 Antibodies in a University Student Population.

PURPOSE: The aim of the study was to determine the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in a university student population. METHODS: This was a cross-sectional survey study based on the World Health Organization population-based seroepidemiological investigational protocol for SARS-CoV-2 conducted between April 29, 2020, and May 8, 2020, examining SARS-CoV-2 antibody prevalence among 790 university students in Los Angeles, CA. Participants completed a questionnaire on potential risk factors before blood sampling. Samples were analyzed using the EUROIMMUN Anti-SARS-CoV-2 ELISA (IgG) for the qualitative detection of IgG class antibodies to SARS-CoV-2 in human serum or plasma. RESULTS: The estimated prevalence of SARS-CoV-2 antibody was 4.0% (3.0%, 5.1%). Factors associated with having a positive test included history of anosmia and/or loss of taste (95% CI: 1.4-9.6). A history of respiratory symptoms, with or without fever, was not associated with a positive antibody test. CONCLUSIONS: Prevalence of SARS-CoV-2 antibodies in the undergraduate and graduate student university population was similar to community prevalence.

Longitudinal observation and decline of neutralizing antibody responses in the three months following SARS-CoV-2 infection in humans.

Antibody responses to SARS-CoV-2 can be detected in most infected individuals 10-15 d after the onset of COVID-19 symptoms. However, due to the recent emergence of SARS-CoV-2 in the human population, it is not known how long antibody responses will be maintained or whether they will provide protection from reinfection. Using sequential serum samples collected up to 94 d post onset of symptoms (POS) from 65 individuals with real-time quantitative PCR-confirmed SARS-CoV-2 infection, we show seroconversion (immunoglobulin (Ig)M, IgA, IgG) in >95% of cases and neutralizing antibody responses when sampled beyond 8 d POS. We show that the kinetics of the neutralizing antibody response is typical of an acute viral infection, with declining neutralizing antibody titres observed after an initial peak, and that the magnitude of this peak is dependent on disease severity. Although some individuals with high peak infective dose (ID50 > 10,000) maintained neutralizing antibody titres >1,000 at >60 d POS, some with lower peak ID50 had neutralizing antibody titres approaching baseline within the follow-up period. A similar decline in neutralizing antibody titres was observed in a cohort of 31 seropositive healthcare workers. The present study has important implications when considering widespread serological testing and antibody protection against reinfection with SARS-CoV-2, and may suggest that vaccine boosters are required to provide long-lasting protection.

Author Correction: A dynamic COVID-19 immune signature includes associations with poor prognosis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A dynamic COVID-19 immune signature includes associations with poor prognosis.

Improved understanding and management of COVID-19, a potentially life-threatening disease, could greatly reduce the threat posed by its etiologic agent, SARS-CoV-2. Toward this end, we have identified a core peripheral blood immune signature across 63 hospital-treated patients with COVID-19 who were otherwise highly heterogeneous. The signature includes discrete changes in B and myelomonocytic cell composition, profoundly altered T cell phenotypes, selective cytokine/chemokine upregulation and SARS-CoV-2-specific antibodies. Some signature traits identify links with other settings of immunoprotection and immunopathology; others, including basophil and plasmacytoid dendritic cell depletion, correlate strongly with disease severity; while a third set of traits, including a triad of IP-10, interleukin-10 and interleukin-6, anticipate subsequent clinical progression. Hence, contingent upon independent validation in other COVID-19 cohorts, individual traits within this signature may collectively and individually guide treatment options; offer insights into COVID-19 pathogenesis; and aid early, risk-based patient stratification that is particularly beneficial in phasic diseases such as COVID-19.

Virtual Sprouts: A Virtual Gardening Pilot Intervention Increases Self-Efficacy to Cook and Eat Fruits and Vegetables in Minority Youth.

OBJECTIVE: To examine the effect of the Virtual Sprouts intervention, an interactive multiplatform mobile gardening game, on dietary intake and psychosocial determinants of dietary behavior in minority youth. MATERIALS AND METHODS: In this quasi-experimental pilot intervention, 180 third-, fourth-, and fifth-grade students in Los Angeles Unified School District participated in a 3-week program that included three Virtual Sprouts gaming sessions, three in-school lessons, and three in-home activities, using a nutrition- and gardening-focused curriculum. Pre- and postintervention questionnaires were used to assess psychosocial determinants of dietary behavior, including knowledge about and self-efficacy to eat fruits and vegetables (FV). Data were collected on FV, whole grains, fiber, total sugar, added sugar, and energy from sugary beverages through the Block Kids Food Screener ("last week" version) for Ages 2-17. Repeated measures analysis of covariance models was used for continuous outcomes, controlling for age, sex, ethnicity, school, and free school lunch. RESULTS: After the intervention, the intervention group (n = 116) compared with the control group (n = 64) had a significantly improved self-efficacy to eat FV score (+1.6% vs. -10.3%, P = 0.01), and an improved self-efficacy to cook FV score (+2.9% vs. -5.0%, P = 0.05). There were no significant differences in dietary intake or self-efficacy to garden scores between intervention and control groups. CONCLUSION: The results from this 3-week pilot study suggest that an interactive mobile game with a nutrition- and gardening-focused curriculum can improve psychosocial determinants of dietary behavior in minority youth.

The Role of Assimilating to the US Culture and the Relationship Between Neighborhood Ethnic Composition and Dietary Intake Among Hispanic Youth.

BACKGROUND: Dietary fiber and sugar intake have been shown to affect metabolic health in overweight Hispanic youth. Evidence on the influence of culture on fiber and sugar intake in Hispanic youth is limited. METHODS: The associations among score for levels of assimilation, neighborhood ethnic characteristics, and daily total and added dietary sugar and dietary fiber intake were assessed using regression analyses. RESULTS: One hundred twenty-four Hispanic youth (age = 13.6 ± 3.0, 106 female) were included. The proportion of Hispanic population in the neighborhood was positively associated with fiber intake (standardized ß = 0.205, p < 0.01) and inversely associated with added (standardized ß = -0.234, p < 0.01) and total sugar intake (standardized ß = -0.229, p < 0.01). Youth's self-identified levels of assimilation inversely moderated (standardized ß = -0.465, p = 0.036) the association between %HP and dietary fiber intake. CONCLUSIONS: Hispanic youth residing in areas of that are predominantly populated with Hispanics may be protected from conforming to unhealthy dietary behaviors. This protective effect is weaker among Hispanic youth with higher level of assimilation.

LA Sprouts: A 12-Week Gardening, Nutrition, and Cooking Randomized Control Trial Improves Determinants of Dietary Behaviors.

OBJECTIVE: To evaluate the effect of an exploratory 12-week nutrition, cooking, and gardening trial (LA Sprouts) on preference for fruit and vegetables (FV); willingness to try FV; identification of FV; self-efficacy to garden, eat, and cook FV; motivation to garden, eat, and cook FV; attitudes toward FV; nutrition and gardening knowledge; and home gardening habits. DESIGN: Randomized controlled trial. SETTING: Four elementary schools. PARTICIPANTS: Three hundred four predominately Hispanic/Latino third- through fifth-grade students were randomized to either the LA Sprouts group (n = 167 students) or control group (n = 137 students). INTERVENTION: Twelve-week after-school nutrition, cooking, and gardening intervention. MAIN OUTCOME MEASURES: Determinants of dietary behavior as measured by questionnaire at baseline and postintervention. ANALYSIS: Analyses of covariance. RESULTS: After the 12-week program, compared with controls, LA Sprouts participants improved scores for identification of vegetables (+11% vs +5%; P = .001) and nutrition and gardening knowledge (+14.5% vs -5.0%; P = .003), and were more likely to garden at home (+7.5% vs -4.4%; P = .003). CONCLUSIONS: The LA Sprouts program positively affected a number of determinants of dietary behaviors that suggest possible mechanisms by which gardening and nutrition education act to improve dietary intake and health outcomes.

Effects of high-sugar and high-fiber meals on physical activity behaviors in Latino and African American adolescents.

OBJECTIVE: This crossover experimental study examined the acute effects of high-sugar/low-fiber (HSLF) vs. low-sugar/high-fiber (LSHF) meals on sedentary behavior (SB) and light-plus activity (L+) in minority adolescents with overweight and obesity. METHODS: 87 Latino and African American adolescents (mean age = 16.3 ± 1.2 years, mean BMI z-score = 2.02 ± 0.52, 56.8% Latino, 51.1% male) underwent two experimental meal conditions during which they consumed HSLF or LSHF meals. Physical activity and SB were measured using accelerometers, and blood glucose and insulin were collected every 30 minutes over 5 hours. Mixed models were used to examine the temporal trends of SB and L+, whether the temporal trends of SB and L+ differed by meal condition, and the influence of blood glucose and insulin on the activity behaviors. RESULTS: SB and L+ fluctuated over time during the HSLF condition but were stable during the LSHF condition. SB and L+ were influenced by the blood glucose response to the HSLF meals. Insulin did not influence SB or L+ in either meal condition. CONCLUSIONS: Sugar and fiber content of meals can have differing acute impacts on activity behaviors in minority adolescents with overweight and obesity, possibly due to differing metabolic responses.

Solitary supratentorial Listeria monocytogenes brain abscess in an immunocompromised patient.

We describe an 81-year-old man receiving azacitidine monotherapy for myelodysplastic syndrome who was improving from Listeria monocytogenes bacteremia after receiving antibiotic therapy during an earlier hospital admission. Shortly after discharge he developed new-onset seizure activity, with brain imaging on subsequent admissions demonstrating a posterior right frontal lobe mass. Specimen cultures after resection of the mass revealed this to be a cerebral abscess related to L. monocytogenes. Brain abscesses related to this organism are rare.

LA sprouts randomized controlled nutrition and gardening program reduces obesity and metabolic risk in Latino youth.

OBJECTIVE: To assess the effects of a 12-week gardening, nutrition, and cooking intervention ("LA Sprouts") on dietary intake, obesity parameters, and metabolic disease risk among low-income, primarily Hispanic/Latino youth in Los Angeles. METHODS: The randomized controlled trial involved four elementary schools [two schools randomized to intervention (172 third-through fifth-grade students); two schools randomized to control (147 third-through fifth-grade students)]. Classes were taught in 90-minute sessions once a week to each grade level for 12 weeks. Data collected at pre- and postintervention included dietary intake via food frequency questionnaire (FFQ), anthropometric measures [BMI, waist circumference (WC)], body fat, and fasting blood samples. RESULTS: LA Sprouts participants had significantly greater reductions in BMI z-scores (0.1-vs. 0.04-point decrease, respectively; P = 0.01) and WC (-1.2 cm vs. no change; P < 0.001). Fewer LA Sprouts participants had the metabolic syndrome (MetSyn) after the intervention than before, while the number of controls with MetSyn increased. LA Sprouts participants had improvements in dietary fiber intake (+3.5% vs. -15.5%; P = 0.04) and less decreases in vegetable intake (-3.6% vs. -26.4%; P = 0.04). Change in fruit intake before and after the intervention did not significantly differ between LA Sprouts and control subjects. CONCLUSIONS: LA Sprouts was effective in reducing obesity and metabolic risk.

Design and methodology of the LA Sprouts nutrition, cooking and gardening program for Latino youth: A randomized controlled intervention.

OBJECTIVE: The LA Sprouts 12-week nutrition, cooking and gardening intervention targets obesity reduction in Latino children. While other gardening and nutrition programs are shown to improve dietary intake, LA Sprouts is unique in that it utilized a curriculum demonstrated to decrease obesity. This methodology paper outlines the design and processes of the LA Sprouts study, and discusses key strategies employed to foster successful implementation of the program. SETTING: After-school program in four Los Angeles elementary schools. SUBJECTS: 3rd-5th grade students. DESIGN: Randomized controlled trial. Gardens were built on two of four school campuses, and the 90-minute weekly lessons focused on strategies to increase fruit and vegetable consumption, gardening at school and home, and cooking healthy meals/snacks. Data collection was conducted pre- and post-intervention and included basic clinical and anthropometric measures, dietary intake and psychosocial constructs measured by questionnaire, and an optional fasting blood draw. RESULTS: Baseline data was collected from 364 children, and 320 (88%) completed follow-up. No participants withdrew from the program (data were missing for other reasons). Intervention students attended 9.7 ± 2.3 lessons. Fasting blood samples were collected on 169 children at baseline, and 113 (67%) at follow-up. Questionnaire scales had good internal consistency (IC) and intra-rater reliability (IRR; in child scales: 88% items with IC > 0.7 and 70% items with IRR > 0.50; in parent scales: 75% items with IC > 0.7). CONCLUSIONS: The intervention was successfully implemented in the schools and scales appear appropriate to evaluate psychosocial constructs relevant to a gardening intervention.

Effects of varying reinforcement probability on pavlovian approach behavior and ultrasonic vocalizations in rats.

Long Evans rats (n=32) were trained for 2 weeks to respond to an auditory conditioned stimulus (CS) which signaled the delivery of a 20% sucrose unconditioned stimulus (US) with varying probabilities. Animals were randomly assigned to 1 of 4 groups. In the control groups, the CS signaled sucrose delivery with equal probabilities across two weeks, at 100% (Group 100-100) and 25% (Group 25-25) respectively. In the experimental groups (Group 100-25) and (Group 25-100), sucrose probabilities were switched between weeks 1 and 2. Three behavioral measures were recorded: latency to enter the sucrose port upon CS presentation, head entries throughout the session and ultrasonic vocalizations. The results suggest that all groups formed associations between the CS and US, as evidenced by a decrease in latency to respond to the CS across days. The experimental groups were also able to detect when sucrose probability changed, as evidenced by Group 25-100's increase in head entries, to the level of Group 100-100 in week 2, and Group 100-25's decrease in head entries, to the level of Group 25-25 in week 2. Group 100-25 also produced an increase in "22 kHz" ultrasonic vocalizations following the downshift on the first day of week 2. The increase in this ultrasonic frequency range, which is associated with negative affect in rats, preceded both the decrease in head entries and the increase in missed trials, consistent with a multistage model of behaviors resulting from US probability reduction.