Serological assessment of the durability of vaccine-mediated protection against SARS-CoV-2 infection.

Virus-neutralizing antibodies are often accepted as a correlate of protection against infection, though questions remain about which components of the immune response protect against SARS-CoV-2 infection. In this small observational study, we longitudinally measured spike receptor binding domain (RBD)-specific and nucleocapsid (NP)-specific serum IgG in a human cohort immunized with the Pfizer BNT162b2 vaccine. NP is not encoded in the vaccine, so an NP-specific response is serological evidence of natural infection. A greater than fourfold increase in NP-specific antibodies was used as the serological marker of infection. Using the RBD-specific IgG titers prior to seroconversion for NP, we calculated a protective threshold for RBD-specific IgG. On average, the RBD-specific IgG response wanes below the protective threshold 169 days following vaccination. Many participants without a history of a positive test result for SARS-CoV-2 infection seroconverted for NP-specific IgG. As a group, participants who seroconverted for NP-specific IgG had significantly higher levels of RBD-specific IgG following NP-seroconversion. RBD-specific IgG titers may serve as one correlate of protection against SARS-CoV-2 infection. These titers wane below the proposed protective threshold approximately six months following immunization. Based on serological evidence of infection, the frequency of breakthrough infections and consequently the level of SARS-CoV-2-specific immunity in the population may be higher than what is predicted based on the frequency of documented infections.

The Substance and Circumstances of Race and Immigration Talk in High School Gender and Sexuality Alliances.

Gender & Sexuality Alliances (GSAs) are school-based clubs that support youth of diverse sexual orientations and gender identities. As identity-centered spaces, GSAs could also foster discussions related to race and immigration (i.e., race and immigration talk). We conducted semi-structured interviews from 2016 to 2018 with 38 GSA members (ages 13-20 years old) of diverse racial/ethnic, immigrant-origin (first and second generations in the United States born of immigrant parents), sexual orientation, and gender identities. Race and immigration talk often occurred when discussing current events (e.g., the 2016 US Presidential Election). Students reported that race and immigration talk depended on representation (i.e., GSA demographics), if it was deemed personally relevant to members, and whether students perceived issues of race and immigration as part of the agenda of the GSA. Some students indicated motivation to discuss racism and nativism yet refrained from doing so due to discomfort or fear of misspeaking. Overall, youth primarily viewed the GSA as a space for LGBTQIA+-oriented discussions and support yet expressed potential for fostering productive race and immigration talk in GSAs given the ongoing US sociopolitical climate. Discussions facilitated by advisors focusing on inter-connected oppression (e.g., intersections of racism and heterosexism) and that leverage brave space discussion dynamics may help students develop competencies to engage in race and immigration talk.

Elucidating the Inhibitory Effect of Resveratrol and Its Structural Analogs on Selected Nucleotide-Related Enzymes.

Resveratrol, the most widely studied natural phytochemical, has been shown to interact with different target proteins. Previous studies show that resveratrol binds and inhibits DNA polymerases and some other enzymes; however, the binding and functioning mechanisms remain unknown. The elucidated knowledge of inhibitory mechanisms of resveratrol will assist us in new drug discovery. We utilized molecular docking and molecular dynamics (MD) simulation to reveal how resveratrol and structurally similar compounds bind to various nucleotide-dependent enzymes, specifically, DNA polymerases, HIV-1 reverse transcriptase, and ribonucleotide reductase. The results show that resveratrol and its analogs exert their inhibitory effects by competing with the substrate dNTPs in these enzymes and blocking elongation of chain polymerization. In addition, the results imply that resveratrol binds to a variety of other ATP-/NTP-binding proteins.

The skin microbiome of elasmobranchs follows phylosymbiosis, but in teleost fishes, the microbiomes converge.

BACKGROUND: The vertebrate clade diverged into Chondrichthyes (sharks, rays, and chimeras) and Osteichthyes fishes (bony fishes) approximately 420 mya, with each group accumulating vast anatomical and physiological differences, including skin properties. The skin of Chondrichthyes fishes is covered in dermal denticles, whereas Osteichthyes fishes are covered in scales and are mucous rich. The divergence time among these two fish groups is hypothesized to result in predictable variation among symbionts. Here, using shotgun metagenomics, we test if patterns of diversity in the skin surface microbiome across the two fish clades match predictions made by phylosymbiosis theory. We hypothesize (1) the skin microbiome will be host and clade-specific, (2) evolutionary difference in elasmobranch and teleost will correspond with a concomitant increase in host-microbiome dissimilarity, and (3) the skin structure of the two groups will affect the taxonomic and functional composition of the microbiomes. RESULTS: We show that the taxonomic and functional composition of the microbiomes is host-specific. Teleost fish had lower average microbiome within clade similarity compared to among clade comparison, but their composition is not different among clade in a null based model. Elasmobranch's average similarity within clade was not different than across clade and not different in a null based model of comparison. In the comparison of host distance with microbiome distance, we found that the taxonomic composition of the microbiome was related to host distance for the elasmobranchs, but not the teleost fishes. In comparison, the gene function composition was not related to the host-organism distance for elasmobranchs but was negatively correlated with host distance for teleost fishes. CONCLUSION: Our results show the patterns of phylosymbiosis are not consistent across both fish clades, with the elasmobranchs showing phylosymbiosis, while the teleost fish are not. The discrepancy may be linked to alternative processes underpinning microbiome assemblage, including possible historical host-microbiome evolution of the elasmobranchs and convergent evolution in the teleost which filter specific microbial groups. Our comparison of the microbiomes among fishes represents an investigation into the microbial relationships of the oldest divergence of extant vertebrate hosts and reveals that microbial relationships are not consistent across evolutionary timescales. Video abstract.

Avoiding the fatal misdiagnosis of pregnancy in a noncommunicating rudimentary horn using 3D transvaginal ultrasound.

Rudimentary horn pregnancies are an increasingly recognized complication of Mullerian duct anomalies. They can lead to uterine rupture with severe maternal morbidity and mortality. We present the case of a 28-year-old woman with a prior surgical diagnosis of bicornuate uterus who was diagnosed with a 7-week pregnancy in the left horn of a bicornuate uterus by 2D ultrasound. Further investigation with 3D ultrasound revealed that the pregnancy was within a noncommunicating rudimentary horn of a unicornuate uterus. These findings were confirmed at laparotomy. This case illustrates the importance and benefits of utilizing 3D ultrasound in diagnosing suspected Mullerian anomalies.

Polyaniline-Functionalized Nanofibers for Colorimetric Detection of HCl Vapor.

Hydrogen chloride (HCl) gas is a hazardous byproduct of industrial processes. Colorimetric approaches to facilitate portable and remote detection are especially desirable. We graft polyaniline to the surface of electrospun nylon nanofibers to minimize mass transfer. Using the resulting nanofibers, we demonstrate colorimetric detection of HCl at sub-ppm levels. We investigated the reusability of the fibers and observed a twofold increase in the limit of detection with multiple uses because of dedoping of the PANi indicated by elemental analysis. The limit of detection using visual detection was compared to spectrophotometric analysis. The ΔE from CIE LAB color space analysis via diffuse reflectance spectroscopy enhances the limit of detection by ∼fivefold when compared to visual detection. This analysis is a promising approach for remote detection using simple commercial digital cameras to achieve low limits of detection.

Impact of MRI on changing management of the cervical spine in blunt trauma patients with a 'negative' CT scan.

BACKGROUND: Owing to the potential risks associated with missed injury, many blunt trauma patients with suspected cervical spine injury undergo some form of imaging technique which has progressed from primarily using plain radiography to relying on CT. Recently, studies have shown that in certain situations, adding MRI may improve the diagnostic accuracy over solely relying on CT. METHODS: Retrospective study of 3468 adult blunt trauma patients at a level I trauma center of which 94 with an initial negative CT scan underwent subsequent MRI. These 94 patients were classified as reliable or unreliable for examination; coded as either having a positive or negative MRI result; and assessed for a change in management. RESULTS: Of the 94 patients in the study population, 69 (73.4%) were deemed reliable and 25 (26.6%) deemed unreliable for examination. Overall, 65 (69.1%) patients had a positive MRI result-49 (71.0%) reliable and 16 (64.0%) unreliable-with some patients testing positive for more than one finding. There was no significant difference in positive MRI rates between reliable and unreliable patients. None of the 29 patients who had negative MRI had a change in management, while 31 of the 65 (47.7%) patients with positive MRI did have a change in management of either continued cervical collar immobilization or neck surgery. CONCLUSIONS: The use of CT scans should be continued as the primary imaging technique for patients with suspected cervical spine injuries. In cases where obtundation or clinical suspicion exists for a false-negative CT scan, MRI should be considered as a supplement and should not be rejected solely based on the negative result of the CT. LEVEL OF EVIDENCE: Level IV.

Denitrifying and diazotrophic community responses to artificial warming in permafrost and tallgrass prairie soils.

Increasing temperatures have been shown to impact soil biogeochemical processes, although the corresponding changes to the underlying microbial functional communities are not well understood. Alterations in the nitrogen (N) cycling functional component are particularly important as N availability can affect microbial decomposition rates of soil organic matter and influence plant productivity. To assess changes in the microbial component responsible for these changes, the composition of the N-fixing (nifH), and denitrifying (nirS, nirK, nosZ) soil microbial communities was assessed by targeted pyrosequencing of functional genes involved in N cycling in two major biomes where the experimental effect of climate warming is under investigation, a tallgrass prairie in Oklahoma (OK) and the active layer above permafrost in Alaska (AK). Raw reads were processed for quality, translated with frameshift correction, and a total of 313,842 amino acid sequences were clustered and linked to a nearest neighbor using reference datasets. The number of OTUs recovered ranged from 231 (NifH) to 862 (NirK). The N functional microbial communities of the prairie, which had experienced a decade of experimental warming were the most affected with changes in the richness and/or overall structure of NifH, NirS, NirK and NosZ. In contrast, the AK permafrost communities, which had experienced only 1 year of warming, showed decreased richness and a structural change only with the nirK-harboring bacterial community. A highly divergent nirK-harboring bacterial community was identified in the permafrost soils, suggesting much novelty, while other N functional communities exhibited similar relatedness to the reference databases, regardless of site. Prairie and permafrost soils also harbored highly divergent communities due mostly to differing major populations.

Fungal community structure in disease suppressive soils assessed by 28S LSU gene sequencing.

Natural biological suppression of soil-borne diseases is a function of the activity and composition of soil microbial communities. Soil microbe and phytopathogen interactions can occur prior to crop sowing and/or in the rhizosphere, subsequently influencing both plant growth and productivity. Research on suppressive microbial communities has concentrated on bacteria although fungi can also influence soil-borne disease. Fungi were analyzed in co-located soils 'suppressive' or 'non-suppressive' for disease caused by Rhizoctonia solani AG 8 at two sites in South Australia using 454 pyrosequencing targeting the fungal 28S LSU rRNA gene. DNA was extracted from a minimum of 125 g of soil per replicate to reduce the micro-scale community variability, and from soil samples taken at sowing and from the rhizosphere at 7 weeks to cover the peak Rhizoctonia infection period. A total of ∼ 994,000 reads were classified into 917 genera covering 54% of the RDP Fungal Classifier database, a high diversity for an alkaline, low organic matter soil. Statistical analyses and community ordinations revealed significant differences in fungal community composition between suppressive and non-suppressive soil and between soil type/location. The majority of differences associated with suppressive soils were attributed to less than 40 genera including a number of endophytic species with plant pathogen suppression potentials and mycoparasites such as Xylaria spp. Non-suppressive soils were dominated by Alternaria, Gibberella and Penicillum. Pyrosequencing generated a detailed description of fungal community structure and identified candidate taxa that may influence pathogen-plant interactions in stable disease suppression.