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Abstract The rise of antibiotic resistance is a critical public health concern, requiring an understanding of mechanisms that enable bacteria to tolerate antimicrobial agents. Bacteria use diverse strategies, including the amplification of drug-resistance genes. In this paper, we showed that multicopy plasmids, often carrying antibiotic resistance genes in clinical bacteria, can rapidly amplify genes, leading to plasmid-mediated phenotypic noise and transient antibiotic resistance. By combining stochastic simulations of a computational model with high-throughput single-cell measurements of b l a TEM-1 expression in Escherichia coli MG1655, we showed that plasmid copy number variability stably maintains populations composed of cells with both low and high plasmid copy numbers. This diversity in plasmid copy number enhances the probability of bacterial survival in the presence of antibiotics, while also rapidly reducing the burden of carrying multiple plasmids in drug-free environments. Our results further support the tenet that multicopy plasmids not only act as vehicles for the horizontal transfer of genetic information between cells but also as drivers of bacterial adaptation, enabling rapid modulation of gene copy numbers. Understanding the role of multicopy plasmids in antibiotic resistance is critical, and our study provides insights into how bacteria can transiently survive lethal concentrations of antibiotics.

Summary: Background: Community stigma against people with opioid use disorder (OUD) and intervention stigma (e.g., toward naloxone) exacerbate the opioid overdose crisis. We examined the effects of the Communities that HEAL (CTH) intervention on perceived opioid-related community stigma by stakeholders in the HEALing Communities Study (HCS). Methods: We collected three surveys from community coalition members in 66 communities across four states participating in HCS. Communities were randomized into Intervention (Wave 1) or Wait-list Control (Wave 2) arms. We conducted multilevel linear mixed models to compare changes in primary outcomes of community stigma toward people treated for OUD, naloxone, and medication for opioid use disorder (MOUD) by arm from time 1 (before the start of the intervention) to time 3 (end of the intervention period in the Intervention arm). Findings: Intervention stakeholders reported a larger decrease in perceived community stigma toward people treated for OUD (adjusted mean change (AMC) −3.20 [95% C.I. −4.43, −1.98]) and toward MOUD (AMC −0.33 [95% C.I. −0.56, −0.09]) than stakeholders in Wait-list Control communities (AMC −0.18 [95% C.I. −1.38, 1.02], p = 0.0007 and AMC 0.11 [95% C.I. −0.09, 0.31], p = 0.0066). The relationship between intervention status and change in stigma toward MOUD was moderated by rural-urban status (urban AMC −0.59 [95% CI, −0.87, −0.32], rural AMC not sig.) and state. The difference in stigma toward naloxone between Intervention and Wait-list Control stakeholders was not statistically significant (p = 0.18). Interpretation: The CTH intervention decreased stakeholder perceptions of community stigma toward people treated for OUD and stigma toward MOUD. Implementing the CTH intervention in other communities could decrease OUD stigma across diverse settings nationally. Funding: US National Institute on Drug Abuse.

Abstract Antibiotic resistance poses a global health threat, but the within-host drivers of resistance remain poorly understood. Pathogen populations are often assumed to be clonal within hosts, and resistance is thought to emerge due to selection for de novo variants. Here we show that mixed strain populations are common in the opportunistic pathogen P. aeruginosa. Crucially, resistance evolves rapidly in patients colonized by multiple strains through selection for pre-existing resistant strains. In contrast, resistance evolves sporadically in patients colonized by single strains due to selection for novel resistance mutations. However, strong trade-offs between resistance and growth rate occur in mixed strain populations, suggesting that within-host diversity can also drive the loss of resistance in the absence of antibiotic treatment. In summary, we show that the within-host diversity of pathogen populations plays a key role in shaping the emergence of resistance in response to treatment.

IntroductionFunctional informaton is introduced as the mechanism to adapt cancer therapies uniquely to individual patients based on changes defined by qualified tumor biomarkers.MethodsTo demonstrate the methodology, a tumor volume biomarker model, characterized by a tumor volume reduction rate coefficient, is used to adapt a tumor cell survival bioresponse radiotherapy model in terms of therapeutic radiation dose. Tumor volume, acquired from imaging data, serves as a surrogate measurement for tumor cell death, but the biomarker model derived from this data cannot be used to calculate the radiation dose absorbed by the target tumor. However, functional information does provide a mathematical connection between the tumor volume biomarker model and the tumor cell survival bioresponse model by quantifying both data sets in the units of information, thus creating an analytic conduit from bioresponse to biomarker.ResultsThe information guided process for individualized dose adaptations using information values acquired from the tumor cell survival bioresponse model and the tumor volume biomarker model are presented in detailed form by flowchart and tabular data. Clinical data are used to generate a presentation that assists investigator application of the information guided methodology to adaptive cancer therapy research.ConclusionsInformation guided adaptation of bioresponse using surrogate data is extensible across multiple research fields because functional information mathematically connects disparate bioresponse and biomarker data sets. Thus, functional information offers adaptive cancer therapy by mathematically connecting immunotherapy, chemotherapy, and radiotherapy cancer treatment processes to implement individualized treatment plans.

In this paper the authors show that the pathogenic bacterium Pseudomonas aeruginosa migrates between the gut and lungs of an ICU patient, and that differential evolutionary responses to antibiotic treatment occur in these organs.

ABSTRACT Integrons are mobile genetic elements that have played an important role in the dissemination of antibiotic resistance. Under stress, the integron can generate combinatorial variation in resistance cassette expression by cassette reshuffling, accelerating the evolution of resistance. However, the flexibility of the integron integrase site recognition motif hints at potential off-target effects of the integrase on the rest of the genome that may have important evolutionary consequences. Here, we test this hypothesis by selecting for increased-piperacillin-resistance populations of Pseudomonas aeruginosa with a mobile integron containing a difficult-to-mobilize β-lactamase cassette to minimize the potential for adaptive cassette reshuffling. We found that integron activity can decrease the overall survival rate but also improve the fitness of the surviving populations. Off-target inversions mediated by the integron accelerated plasmid adaptation by disrupting costly conjugative genes otherwise mutated in control populations lacking a functional integrase. Plasmids containing integron-mediated inversions were associated with lower plasmid costs and higher stability than plasmids carrying mutations albeit at the cost of a reduced conjugative ability. These findings highlight the potential for integrons to create structural variation that can drive bacterial evolution, and they provide an interesting example showing how antibiotic pressure can drive the loss of conjugative genes. IMPORTANCE Tackling the public health challenge created by antibiotic resistance requires understanding the mechanisms driving its evolution. Mobile integrons are widespread genetic platforms heavily involved in the spread of antibiotic resistance. Through the action of the integrase enzyme, integrons allow bacteria to capture, excise, and shuffle antibiotic resistance gene cassettes. This integrase enzyme is characterized by its ability to recognize a wide range of recombination sites, which allows it to easily capture diverse resistance cassettes but which may also lead to off-target reactions with the rest of the genome. Using experimental evolution, we tested the off-target impact of integron activity. We found that integrons increased the fitness of the surviving bacteria through extensive genomic rearrangements of the plasmids carrying the integrons, reducing their ability to spread horizontally. These results show that integrons not only accelerate resistance evolution but also can generate extensive structural variation, driving bacterial evolution beyond antibiotic resistance.

Many plasmids can be transferred between bacterial cells via conjugation; however, the mechanisms underlying the transfer of non-conjugative plasmids are less clear. Here, Humphrey et al. show that staphylococcal phages and a family of pathogenicity islands (PICIs) can mediate intra- and inter-species plasmid transfer via generalised transduction.

Highlights It is now established that men and women respond differently to infection from COVID-19 and that clinical outcomes from this infection are more severe in men. Studies still neglect to include more women in clinical trials despite substantial differences between sexes in these outcomes. Neglecting to include women or enough women in research studies on COVID-19 can lead to recommendations that are not appropriate for women or even recommendations that harm their health. Pandemic research and medical research in general could be transformed by focusing more on sex-specific effects of disease and treatment.

Modular, rather than integrated systems are classically thought to allow functional diversity to evolve rapidly. A study of cichlid fish shows integration between divergent jaw systems at the phylogenetic, population, and genetic scales, suggesting integration can and does facilitate rapid, coordinated trait evolution.

A patient with severe mitral regurgitation and chronic systolic heart failure taking inotropic support at home presents for transcatheter edge-to-edge mitral valve repair, complicated by torrential mitral regurgitation from damaged mitral leaflets requiring escalating mechanical circulatory support and ultimately expedited orthotopic heart transplantation. (Level of Difficulty: Intermediate.)

Abstract While anthropogenic disturbances can have damaging effects on biodiversity, they also offer an opportunity to understand how species adapt to new environments and may even provide insights into the earliest stages of evolutionary diversification. With these topics in mind, we explored the morphological changes that have occurred across several cichlid species following the damming of the Tocantins River, Brazil. The Tocantins was once a large (2,450 km), contiguous river system; however, upon closure of the Tucuruí Hydroelectric Dam in 1984, a large (~2,850 km2), permanent reservoir was established. We used geometric morphometrics to evaluate changes in native cichlids, comparing historical museum specimens collected from the Tocantins to contemporary specimens collected from the Tucuruí reservoir. Six species across five genera were included to represent distinct ecomorphs, from large piscivores to relatively small opportunistic omnivores. Notably, statistically significant changes in shape and morphological disparity were observed in all species. Moreover, the documented changes tended to be associated with functionally relevant aspects of anatomy, including head, fin, and body shape. Our data offer insights into the ways cichlids have responded, morphologically, to a novel lake environment and provide a robust foundation for exploring the mechanisms through which these changes have occurred.

Rare earth elements are used in electronics, but increase in demand could lead to low supply. Here the authors conduct experiments on the International Space Station and show microbes can extract rare elements from rocks at low gravity, a finding that could extend mining potential to other planets.

Some bacterial lineages appear to be pre-disposed to evolving antibiotic resistance. Here, the authors show that differential expression of an efflux pump causes widespread variation in evolvability across Staphylococcus aureus isolates, and chemical inhibition of the pump prevents resistance evolution.

Abstract Background Adaptive radiations are characterized by extreme and/or iterative phenotypic divergence; however, such variation does not accumulate evenly across an organism. Instead, it is often partitioned into sub-units, or modules, which can differentially respond to selection. While it is recognized that changing the pattern of modularity or the strength of covariation (integration) can influence the range or rate of morphological evolution, the relationship between shape variation and covariation remains unclear. For example, it is possible that rapid phenotypic change requires concomitant changes to the underlying covariance structure. Alternatively, repeated shifts between phenotypic states may be facilitated by a conserved covariance structure. Distinguishing between these scenarios will contribute to a better understanding of the factors that shape biodiversity. Here, we explore these questions using a diverse Lake Malawi cichlid species complex, Tropheops, that appears to partition habitat by depth. Results We construct a phylogeny of Tropheops populations and use 3D geometric morphometrics to assess the shape of four bones involved in feeding (mandible, pharyngeal jaw, maxilla, pre-maxilla) in populations that inhabit deep versus shallow habitats. We next test numerous modularity hypotheses to understand whether fish at different depths are characterized by conserved or divergent patterns of modularity. We further examine rates of morphological evolution and disparity between habitats and among modules. Finally, we raise a single Tropheops species in environments mimicking deep or shallow habitats to discover whether plasticity can replicate the pattern of morphology, disparity, or modularity observed in natural populations. Conclusions Our data support the hypothesis that conserved patterns of modularity permit the evolution of divergent morphologies and may facilitate the repeated transitions between habitats. In addition, we find the lab-reared populations replicate many trends in the natural populations, which suggests that plasticity may be an important force in initiating depth transitions, priming the feeding apparatus for evolutionary change.

Background Neuronal dysfunction plays an important role in the high prevalence of HIV-associated neurocognitive disorders (HAND) in people with HIV (PWH). Transcranial direct current stimulation (tDCS)—with its capability to improve neuronal function—may have the potential to serve as an alternative therapeutic approach for HAND. Brain imaging and neurobehavioral studies provide converging evidence that injury to the anterior cingulate cortex (ACC) is highly prevalent and contributes to HAND in PWH, suggesting that ACC may serve as a potential neuromodulation target for HAND. Here we conducted a randomized, double-blind, placebo-controlled, partial crossover pilot study to test the safety, tolerability, and potential efficacy of anodal tDCS over cingulate cortex in adults with HIV, with a focus on the dorsal ACC (dACC). Methods Eleven PWH (47–69 years old, 2 females, 100% African Americans, disease duration 16–36 years) participated in the study, which had two phases, Phase 1 and Phase 2. During Phase 1, participants were randomized to receive ten sessions of sham (n = 4) or cingulate tDCS (n = 7) over the course of 2–3 weeks. Treatment assignments were unknown to the participants and the technicians. Neuropsychology and MRI data were collected from four additional study visits to assess treatment effects, including one baseline visit (BL, prior to treatment) and three follow-up visits (FU1, FU2, and FU3, approximately 1 week, 3 weeks, and 3 months after treatment, respectively). Treatment assignment was unblinded after FU3. Participants in the sham group repeated the study with open-label cingulate tDCS during Phase 2. Statistical analysis was limited to data from Phase 1. Results Compared to sham tDCS, cingulate tDCS led to a decrease in Perseverative Errors in Wisconsin Card Sorting Test (WCST), but not Non-Perseverative Errors, as well as a decrease in the ratio score of Trail Making Test—Part B (TMT-B) to TMT—Part A (TMT-A). Seed-to-voxel analysis with resting state functional MRI data revealed an increase in functional connectivity between the bilateral dACC and a cluster in the right dorsal striatum after cingulate tDCS. There were no differences in self-reported discomfort ratings between sham and cingulate tDCS. Conclusions Cingulate tDCS is safe and well-tolerated in PWH, and may have the potential to improve cognitive performance and brain function. A future study with a larger sample is warranted.

ABSTRACT Selection plays a key role in the spread of antibiotic resistance, but the evolutionary drivers of clinically important resistant strains remain poorly understood. Here, we use genomic analyses and competition experiments to study Staphylococcus aureus ST239, a prominent MRSA strain that is thought to have been formed by large-scale recombination between ST8 and ST30. Genomic analyses allowed us to refine the hybrid model for the origin of ST239 and to date the origin of ST239 to 1920 to 1945, which predates the clinical introduction of methicillin in 1959. Although purifying selection has dominated the evolution of ST239, parallel evolution has occurred in genes involved in antibiotic resistance and virulence, suggesting that ST239 has evolved toward an increasingly pathogenic lifestyle. Crucially, ST239 isolates have low competitive fitness relative to both ST8 and ST30 isolates, supporting the idea that fitness costs have driven the demise of this once-dominant pathogen strain. IMPORTANCE The rise of antibiotic resistance in most pathogenic bacteria has been driven by the spread of a small number of epidemically successful resistant strains. However, the processes that drive the rise and fall of these “superbugs” remain poorly understood. In our study, we investigated Staphylococcus aureus ST239, an important MRSA strain that has been a leading cause of serious hospital-acquired infections. We show here that ST239 was formed by the exchange of a very large fragment of DNA carrying resistance genes between strains of S. aureus sometime before 1945. The introduction of the antibiotic methicillin in 1959 provided a key advantage for Methicillin-Resistant Staphylococcus aureus (MRSA) strains. Interestingly, we found that ST239 has low competitive ability compared to other strains of S. aureus, and this evolutionary hindrance may explain why the prevalence of ST239 has declined precipitously at a global scale.

As humans explore and settle in space, they will need to mine elements to support industries such as manufacturing and construction. In preparation for the establishment of permanent human settlements across the Solar System, we conducted the ESA BioRock experiment on board the International Space Station to investigate whether biological mining could be accomplished under extraterrestrial gravity conditions. We tested the hypothesis that the gravity (g) level influenced the efficacy with which biomining could be achieved from basalt, an abundant material on the Moon and Mars, by quantifying bioleaching by three different microorganisms under microgravity, simulated Mars and Earth gravitational conditions. One element of interest in mining is vanadium (V), which is added to steel to fabricate high strength, corrosion-resistant structural materials for buildings, transportation, tools and other applications. The results showed that Sphingomonas desiccabilis and Bacillus subtilis enhanced the leaching of vanadium under the three gravity conditions compared to sterile controls by 184.92 to 283.22%, respectively. Gravity did not have a significant effect on mean leaching, thus showing the potential for biomining on Solar System objects with diverse gravitational conditions. Our results demonstrate the potential to use microorganisms to conduct elemental mining and other bioindustrial processes in space locations with non-1 × g gravity. These same principles apply to extraterrestrial bioremediation and elemental recycling beyond Earth.

Summary: Monitoring microbial communities aboard the International Space Station (ISS) is essential to maintaining astronaut health and the integrity of life-support systems. Using assembled genomes of ISS-derived microbial isolates as references, recruiting metagenomic reads from an astronaut's nasal microbiome revealed no recruitment to a Staphylococcus aureus isolate from samples before launch, yet systematic recruitment across the genome when sampled after 3 months aboard the ISS, with a median percent identity of 100%. This suggests that either a highly similar S. aureus population colonized the astronaut's nasal microbiome while the astronaut was aboard the ISS or that it may have been below detection before spaceflight, instead supporting a shift in community composition. This work highlights the value in generating genomic libraries of microbes from built-environments such as the ISS and demonstrates one way such data can be integrated with metagenomics to facilitate the tracking and monitoring of astronaut microbiomes and health.

Microorganisms perform countless tasks on Earth and they are expected to be essential for human space exploration. Despite the interest in the responses of bacteria to space conditions, the findings on the effects of microgravity have been contradictory, while the effects of Martian gravity are nearly unknown. We performed the ESA BioRock experiment on the International Space Station to study microbe-mineral interactions in microgravity, simulated Mars gravity and simulated Earth gravity, as well as in ground gravity controls, with three bacterial species: Sphingomonas desiccabilis, Bacillus subtilis, and Cupriavidus metallidurans. To our knowledge, this was the first experiment to study simulated Martian gravity on bacteria using a space platform. Here, we tested the hypothesis that different gravity regimens can influence the final cell concentrations achieved after a multi-week period in space. Despite the different sedimentation rates predicted, we found no significant differences in final cell counts and optical densities between the three gravity regimens on the ISS. This suggests that possible gravity-related effects on bacterial growth were overcome by the end of the experiment. The results indicate that microbial-supported bioproduction and life support systems can be effectively performed in space (e.g., Mars), as on Earth.

Introduction: Many transgender people take hormone therapy to affirm their gender identity. One potential long-term consequence of gender affirming hormone therapy is increased body mass index (BMI), which may be associated with metabolic syndrome, cardiovascular disease and higher mortality. Only a few published studies explored changes in BMI in transgender people taking gender affirming hormone therapy (GAHT). Objective: To examine the changes in BMI longitudinally in response to GAHT in transgender women and men. Methods: We conducted a retrospective cohort study of transgender individuals who received GAHT from the endocrinology clinic between January 1, 2000 and September 6, 2018. Subjects who sought GAHT were included if they had two separate measurements of BMI and were excluded if they had a BMI greater than 35 kg/m2 or were missing demographic data at entry. We used a linear mixed model to analyze the longitudinal change in BMI. Results: There were a total of 227 subjects included in this cohort. Among subjects already on GAHT, transgender women were receiving GAHT longer than transgender men (6.59 ± 9.35 vs 3.67 ± 3.43 years, p-value = 0.04). Over the period of 7 years, there was a significant increase in BMI in transwomen who newly initiated GAHT (p-value 0.004). There were no changes in BMI in transgender men and women already on GAHT or in transgender men who newly initiated GAHT in the study. Conclusion: We conclude that BMI significantly increases in transwomen but not in transmen after initiation of GAHT in a single center based in the United States. In transwomen and transmen, BMI appears to be stable following 3 to 6 years of GAHT. Future investigations should examine the causes for increased BMI in transgender women including type of GAHT, diet and lifestyle, and association with risk of metabolic syndrome and cardiovascular disease.

The Brazilian HIV/AIDS epidemic is concentrated among men who have sex with men (MSM), however HIV testing rates among MSM are not commensurate with their risk. Strategies to expand early diagnosis may include use of self-conducted home-based testing kits, which are now available for purchase in the US. In April 2011 we conducted a survey with Brazilian MSM using Facebook to assess HIV testing preferences and acceptability of home-based testing. Among 356 previously tested, HIV-negative MSM, 47% reported a preference for home-based testing, 27% preferred clinic-based testing, and 26% had no preference. Less frequent testers and those who had considered testing but failed to test were more likely to prefer home-based testing. Close to 90% reported that they would use self-test kits; 62% and 54% said they would use home-based testing to make choices about unprotected sex with regular and new partners, respectively. Concerns included difficulty to understand the tests (32%) and receiving results alone (23%). Overall, home-based testing may appeal to MSM and result in increased testing frequency. Research on feasibility and utilization of self-tests in practice is needed.

Somatic cell reprogramming toward induced pluripotent stem cells (iPSCs) holds great promise in future regenerative medicine. However, the reprogramming process mediated by the traditional defined factors (OSMK) is slow and extremely inefficient. Here, we develop a combination of modified reprogramming factors (OySyNyK) in which the transactivation domain of the Yes-associated protein is fused to defined factors and establish a highly efficient and rapid reprogramming system. We show that the efficiency of OySyNyK-induced iPSCs is up to 100-fold higher than the OSNK and the reprogramming by OySyNyK is very rapid and is initiated in 24 hr. We find that OySyNyK factors significantly increase Tet1 expression at the early stage and interact with Tet1/2 to promote reprogramming. Our studies not only establish a rapid and highly efficient iPSC reprogramming system but also uncover a mechanism by which engineered factors coordinate with TETs to regulate 5hmC-mediated epigenetic control.

ABSTRACT Although it is becoming clear that many microbial primary producers can also play a role as organic consumers, we know very little about the metabolic regulation of photoautotroph organic matter consumption. Cyanobacteria in phototrophic biofilms can reuse extracellular organic carbon, but the metabolic drivers of extracellular processes are surprisingly complex. We investigated the metabolic foundations of organic matter reuse by comparing exoproteome composition and incorporation of 13C-labeled and 15N-labeled cyanobacterial extracellular organic matter (EOM) in a unicyanobacterial biofilm incubated using different light regimes. In the light and the dark, cyanobacterial direct organic C assimilation accounted for 32% and 43%, respectively, of all organic C assimilation in the community. Under photosynthesis conditions, we measured increased excretion of extracellular polymeric substances (EPS) and proteins involved in micronutrient transport, suggesting that requirements for micronutrients may drive EOM assimilation during daylight hours. This interpretation was supported by photosynthesis inhibition experiments, in which cyanobacteria incorporated N-rich EOM-derived material. In contrast, under dark, C-starved conditions, cyanobacteria incorporated C-rich EOM-derived organic matter, decreased excretion of EPS, and showed an increased abundance of degradative exoproteins, demonstrating the use of the extracellular domain for C storage. Sequence-structure modeling of one of these exoproteins predicted a specific hydrolytic activity that was subsequently detected, confirming increased EOM degradation in the dark. Associated heterotrophic bacteria increased in abundance and upregulated transport proteins under dark relative to light conditions. Taken together, our results indicate that biofilm cyanobacteria are successful competitors for organic C and N and that cyanobacterial nutrient and energy requirements control the use of EOM. IMPORTANCE Cyanobacteria are globally distributed primary producers, and the fate of their fixed C influences microbial biogeochemical cycling. This fate is complicated by cyanobacterial degradation and assimilation of organic matter, but because cyanobacteria are assumed to be poor competitors for organic matter consumption, regulation of this process is not well tested. In mats and biofilms, this is especially relevant because cyanobacteria produce an extensive organic extracellular matrix, providing the community with a rich source of nutrients. Light is a well-known regulator of cyanobacterial metabolism, so we characterized the effects of light availability on the incorporation of organic matter. Using stable isotope tracing at the single-cell level, we quantified photoautotroph assimilation under different metabolic conditions and integrated the results with proteomics to elucidate metabolic status. We found that cyanobacteria effectively compete for organic matter in the light and the dark and that nutrient requirements and community interactions contribute to cycling of extracellular organic matter.

Objective. Individuals who seek asylum are frequently fleeing violent persecution and may experience head injury (HI). However, little is known about the prevalence of HI in asylum seekers and refugees (ASR) despite the potential for HI to significantly affect cognitive and emotional functioning and to compromise asylum outcomes. This preliminary study investigates the prevalence of HI in ASR referred to a complex psychological trauma service. Method. Participants were 115 adult ASR referred to a community psychological trauma service with moderate to severe mental health problems associated with psychological trauma. They were screened for a history of HI using a questionnaire developed for the study. Interpreters were used when required. Results. The overall prevalence of HI was 51%. At least 38% of those with HI had a moderate–severe HI that could cause persisting disability. In 53% of those with HI, the cause was torture, human trafficking or domestic violence. Repeat HI can have cumulative effects on function; it was common, and was reported in 68% of those with HI. An injury to the head was not known to mental health clinicians prior to screening in 64% of cases. Conclusion. The emotional and cognitive consequences of HI in ASR may increase the vulnerability of this disadvantaged group, and can be associated with neurobehavioural problems affecting daily life and may compromise asylum outcomes. Routine screening for HI in ASR is needed, as are links to neuropsychology and brain injury services for advice, assessment and intervention.

Abstract: Importance: SARS-CoV-2 infection can result in ongoing, relapsing, or new symptoms or other health effects after the acute phase of infection; termed post-acute sequelae of SARS-CoV-2 infection (PASC), or long COVID. The characteristics, prevalence, trajectory and mechanisms of PASC are ill-defined. The objectives of the Researching COVID to Enhance Recovery (RECOVER) Multi-site Observational Study of PASC in Adults (RECOVER-Adult) are to: (1) characterize PASC prevalence; (2) characterize the symptoms, organ dysfunction, natural history, and distinct phenotypes of PASC; (3) identify demographic, social and clinical risk factors for PASC onset and recovery; and (4) define the biological mechanisms underlying PASC pathogenesis. Methods: RECOVER-Adult is a combined prospective/retrospective cohort currently planned to enroll 14,880 adults aged ≥18 years. Eligible participants either must meet WHO criteria for suspected, probable, or confirmed infection; or must have evidence of no prior infection. Recruitment occurs at 86 sites in 33 U.S. states, Washington, DC and Puerto Rico, via facility– and community-based outreach. Participants complete quarterly questionnaires about symptoms, social determinants, vaccination status, and interim SARS-CoV-2 infections. In addition, participants contribute biospecimens and undergo physical and laboratory examinations at approximately 0, 90 and 180 days from infection or negative test date, and yearly thereafter. Some participants undergo additional testing based on specific criteria or random sampling. Patient representatives provide input on all study processes. The primary study outcome is onset of PASC, measured by signs and symptoms. A paradigm for identifying PASC cases will be defined and updated using supervised and unsupervised learning approaches with cross– validation. Logistic regression and proportional hazards regression will be conducted to investigate associations between risk factors, onset, and resolution of PASC symptoms. Discussion: RECOVER-Adult is the first national, prospective, longitudinal cohort of PASC among US adults. Results of this study are intended to inform public health, spur clinical trials, and expand treatment options.

ABSTRACT Fitness costs play a key role in the evolutionary dynamics of antibiotic resistance in bacteria by generating selection against resistance in the absence of antibiotics. Although the genetic basis of antibiotic resistance is well understood, the precise molecular mechanisms linking the genetic basis of resistance to its fitness cost remain poorly characterized. Here, we examine how the system-wide impacts of mutations in the RNA polymerase (RNAP) gene rpoB shape the fitness cost of rifampin resistance in Pseudomonas aeruginosa. Rifampin resistance mutations reduce transcriptional efficiency, and this explains 76% of the variation in fitness among rpoB mutants. The pleiotropic consequence of rpoB mutations is that mutants show altered relative transcript levels of essential genes. We find no evidence that global transcriptional responses have an impact on the fitness cost of rifampin resistance as revealed by transcriptome sequencing (RNA-Seq). Global changes in the transcriptional profiles of rpoB mutants compared to the transcriptional profile of the rifampin-sensitive ancestral strain are subtle, demonstrating that the transcriptional regulatory network of P. aeruginosa is robust to the decreased transcriptional efficiency associated with rpoB mutations. On a smaller scale, we find that rifampin resistance mutations increase the expression of RNAP due to decreased termination at an attenuator upstream from rpoB, and we argue that this helps to minimize the cost of rifampin resistance by buffering against reduced RNAP activity. In summary, our study shows that it is possible to dissect the molecular mechanisms underpinning variation in the cost of rifampin resistance and highlights the importance of genome-wide buffering of relative transcript levels in providing robustness against resistance mutations. IMPORTANCE Antibiotic resistance mutations carry fitness costs. Relative to the characteristics of their antibiotic-sensitive ancestors, resistant mutants show reduced growth rates and competitive abilities. Fitness cost plays an important role in the evolution of antibiotic resistance in the absence of antibiotics; however, the molecular mechanisms underlying these fitness costs is not well understood. We applied a systems-level approach to dissect the molecular underpinnings of the fitness costs associated with rifampin resistance in P. aeruginosa and showed that most of the variation in fitness cost can be explained by the direct effect of resistance mutations on the enzymatic activity of the mutated gene. Pleiotropic changes in transcriptional profiles are subtle at a genome-wide scale, suggesting that the gene regulatory network of P. aeruginosa is robust in the face of the direct effects of resistance mutations.

M87 is the best source in which to study a jet at high resolution in gravitational units because it has a very high mass black hole and is nearby. The angular size of the black hole is second only to Sgr A*, which does not have a strong jet. The jet structure is edge brightened with a wide opening angle base and a weak counterjet. We have roughly annual observations for 17 years plus intensive monitoring at three week intervals for a year and five day intervals for 2.5 months made with the Very Long Baseline Array (VLBA) at 43 GHz. The inner jet shows very complex dynamics, with apparent motions both along and across the jet. Speeds from zero to over 2c are seen, with acceleration observed over the first 3 milli-arcseconds. The counterjet decreases in brightness much more rapidly than the main jet, as is expected from relativistic beaming in an accelerating jet oriented near the line-of-sight. Details of the structure and dynamics are discussed. The roughly annual observations show side-to-side motion of the whole jet with a characteristic time scale of about 9 years.

M87 is one of the nearest radio galaxies with a central Super-Massive Black Hole (SMBH) and a prominent relativistic jet. Due to its close distance to the observer and the large SMBH mass, the source is one of the best laboratories to obtain strong observational constraints on the theoretical models for the formation and evolution of the AGN jets. In this article, we present preliminary results from our ongoing observational study about the innermost jet of M87 at an ultra-high resolution of ∼50 μ as achieved by the Global Millimeter-Very Long Baseline Interferometry Array (GMVA). The data obtained between 2004 and 2015 clearly show limb-brightened jets at extreme resolution and sensitivity. Our preliminary analysis reveals that the innermost jet expands in an edge-brightened cone structure (parabolic shape) but with the jet expansion profile slightly different from the outer regions of the jet. Brightness temperatures of the Very Long Baseline Interferometry (VLBI) core obtained from cm- to mm-wavelengths show a systematic evolution, which can be interpreted as the evolution as a function of distance from the BH. We also adopt an alternative imaging algorithm, Bi-Spectrum Maximum Entropy Method (BSMEM), to test reliable imaging at higher angular resolution than provided by the standard CLEAN method (i.e., super-resolution). A demonstration with a VLBA 7 mm example data set shows consistent results with a near-in-time 3 mm VLBI image. Application of the method to the 2009 GMVA data yields an image with remarkable fine-scale structures that have been never imaged before. We present a brief interpretation of the complexity in the structure.

BackgroundNeuronal dysfunction plays an important role in the high prevalence of HIV-associated neurocognitive disorders (HAND) in people with HIV (PWH). Transcranial direct current stimulation (tDCS)-with its capability to improve neuronal function-may have the potential to serve as an alternative therapeutic approach for HAND. Brain imaging and neurobehavioral studies provide converging evidence that injury to the anterior cingulate cortex (ACC) is highly prevalent and contributes to HAND in PWH, suggesting that ACC may serve as a potential neuromodulation target for HAND. Here we conducted a randomized, double-blind, placebo-controlled, partial crossover pilot study to test the safety, tolerability, and potential efficacy of anodal tDCS over cingulate cortex in adults with HIV, with a focus on the dorsal ACC (dACC).MethodsEleven PWH (47-69 years old, 2 females, 100% African Americans, disease duration 16-36 years) participated in the study, which had two phases, Phase 1 and Phase 2. During Phase 1, participants were randomized to receive ten sessions of sham (n = 4) or cingulate tDCS (n = 7) over the course of 2-3 weeks. Treatment assignments were unknown to the participants and the technicians. Neuropsychology and MRI data were collected from four additional study visits to assess treatment effects, including one baseline visit (BL, prior to treatment) and three follow-up visits (FU1, FU2, and FU3, approximately 1 week, 3 weeks, and 3 months after treatment, respectively). Treatment assignment was unblinded after FU3. Participants in the sham group repeated the study with open-label cingulate tDCS during Phase 2. Statistical analysis was limited to data from Phase 1.ResultsCompared to sham tDCS, cingulate tDCS led to a decrease in Perseverative Errors in Wisconsin Card Sorting Test (WCST), but not Non-Perseverative Errors, as well as a decrease in the ratio score of Trail Making Test-Part B (TMT-B) to TMT-Part A (TMT-A). Seed-to-voxel analysis with resting state functional MRI data revealed an increase in functional connectivity between the bilateral dACC and a cluster in the right dorsal striatum after cingulate tDCS. There were no differences in self-reported discomfort ratings between sham and cingulate tDCS.ConclusionsCingulate tDCS is safe and well-tolerated in PWH, and may have the potential to improve cognitive performance and brain function. A future study with a larger sample is warranted.