Bacteria hijack a meningeal neuroimmune axis to facilitate brain invasion.

The meninges are densely innervated by nociceptive sensory neurons that mediate pain and headache1,2. Bacterial meningitis causes life-threatening infections of the meninges and central nervous system, affecting more than 2.5 million people a year3-5. How pain and neuroimmune interactions impact meningeal antibacterial host defences are unclear. Here we show that Nav1.8+ nociceptors signal to immune cells in the meninges through the neuropeptide calcitonin gene-related peptide (CGRP) during infection. This neuroimmune axis inhibits host defences and exacerbates bacterial meningitis. Nociceptor neuron ablation reduced meningeal and brain invasion by two bacterial pathogens: Streptococcus pneumoniae and Streptococcus agalactiae. S. pneumoniae activated nociceptors through its pore-forming toxin pneumolysin to release CGRP from nerve terminals. CGRP acted through receptor activity modifying protein 1 (RAMP1) on meningeal macrophages to polarize their transcriptional responses, suppressing macrophage chemokine expression, neutrophil recruitment and dural antimicrobial defences. Macrophage-specific RAMP1 deficiency or pharmacological blockade of RAMP1 enhanced immune responses and bacterial clearance in the meninges and brain. Therefore, bacteria hijack CGRP-RAMP1 signalling in meningeal macrophages to facilitate brain invasion. Targeting this neuroimmune axis in the meninges can enhance host defences and potentially produce treatments for bacterial meningitis.

Bacterial protein domains with a novel Ig-like fold target human CEACAM receptors.

Streptococcus agalactiae, also known as group B Streptococcus (GBS), is the major cause of neonatal sepsis in humans. A critical step to infection is adhesion of bacteria to epithelial surfaces. GBS adhesins have been identified to bind extracellular matrix components and cellular receptors. However, several putative adhesins have no host binding partner characterised. We report here that surface-expressed ß protein of GBS binds to human CEACAM1 and CEACAM5 receptors. A crystal structure of the complex showed that an IgSF domain in ß represents a novel Ig-fold subtype called IgI3, in which unique features allow binding to CEACAM1. Bioinformatic assessment revealed that this newly identified IgI3 fold is not exclusively present in GBS but is predicted to be present in adhesins from other clinically important human pathogens. In agreement with this prediction, we found that CEACAM1 binds to an IgI3 domain found in an adhesin from a different streptococcal species. Overall, our results indicate that the IgI3 fold could provide a broadly applied mechanism for bacteria to target CEACAMs.

Identification of a novel cationic glycolipid in Streptococcus agalactiae that contributes to brain entry and meningitis.

Bacterial membrane lipids are critical for membrane bilayer formation, cell division, protein localization, stress responses, and pathogenesis. Despite their critical roles, membrane lipids have not been fully elucidated for many pathogens. Here, we report the discovery of a novel cationic glycolipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), which is synthesized in high abundance by the bacterium Streptococcus agalactiae (Group B Streptococcus, GBS). To our knowledge, Lys-Glc-DAG is more positively charged than any other known lipids. Lys-Glc-DAG carries 2 positive net charges per molecule, distinct from the widely described lysylated phospholipid lysyl-phosphatidylglycerol (Lys-PG) that carries one positive net charge due to the presence of a negatively charged phosphate moiety. We use normal phase liquid chromatography (NPLC) coupled with electrospray ionization (ESI) high-resolution tandem mass spectrometry (HRMS/MS) and genetic approaches to determine that Lys-Glc-DAG is synthesized by the enzyme MprF in GBS, which covalently modifies the neutral glycolipid Glc-DAG with the cationic amino acid lysine. GBS is a leading cause of neonatal meningitis, which requires traversal of the endothelial blood-brain barrier (BBB). We demonstrate that GBS strains lacking mprF exhibit a significant decrease in the ability to invade BBB endothelial cells. Further, mice challenged with a GBSΔmprF mutant developed bacteremia comparably to wild-type (WT) infected mice yet had less recovered bacteria from brain tissue and a lower incidence of meningitis. Thus, our data suggest that Lys-Glc-DAG may contribute to bacterial uptake into host cells and disease progression. Importantly, our discovery provides a platform for further study of cationic lipids at the host-pathogen interface.

Heterogeneity of the group B streptococcal type VII secretion system and influence on colonization of the female genital tract.

Type VIIb secretion systems (T7SSb) in Gram-positive bacteria facilitate physiology, interbacterial competition, and/or virulence via EssC ATPase-driven secretion of small ɑ-helical proteins and toxins. Recently, we characterized T7SSb in group B Streptococcus (GBS), a leading cause of infection in newborns and immunocompromised adults. GBS T7SS comprises four subtypes based on variation in the C-terminus of EssC and the repertoire of downstream effectors; however, the intraspecies diversity of GBS T7SS and impact on GBS-host interactions remains unknown. Bioinformatic analysis indicates that GBS T7SS loci encode subtype-specific putative effectors, which have low interspecies and inter-subtype homology but contain similar domains/motifs and therefore may serve similar functions. We further identify orphaned GBS WXG100 proteins. Functionally, we show that GBS T7SS subtype I and III strains secrete EsxA in vitro and that in subtype I strain CJB111, esxA1 appears to be differentially transcribed from the T7SS operon. Furthermore, we observe subtype-specific effects of GBS T7SS on host colonization, as CJB111 subtype I but not CNCTC 10/84 subtype III T7SS promotes GBS vaginal colonization. Finally, we observe that T7SS subtypes I and II are the predominant subtypes in clinical GBS isolates. This study highlights the potential impact of T7SS heterogeneity on host-GBS interactions.

Targeting the BspC-vimentin interaction to develop anti-virulence therapies during Group B streptococcal meningitis.

Bacterial infections are a major cause of morbidity and mortality worldwide and the rise of antibiotic resistance necessitates development of alternative treatments. Pathogen adhesins that bind to host cells initiate disease pathogenesis and represent potential therapeutic targets. We have shown previously that the BspC adhesin in Group B Streptococcus (GBS), the leading cause of bacterial neonatal meningitis, interacts with host vimentin to promote attachment to brain endothelium and disease development. Here we determined that the BspC variable (V-) domain contains the vimentin binding site and promotes GBS adherence to brain endothelium. Site directed mutagenesis identified a binding pocket necessary for GBS host cell interaction and development of meningitis. Using a virtual structure-based drug screen we identified compounds that targeted the V-domain binding pocket, which blocked GBS adherence and entry into the brain in vivo. These data indicate the utility of targeting the pathogen-host interface to develop anti-virulence therapeutics.

Staphylococcus aureus Fibronectin-Binding Proteins Contribute to Colonization of the Female Reproductive Tract.

Methicillin-resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen and frequent colonizer of human skin and mucosal membranes, including the vagina, with vaginal colonization reaching nearly 25% in some pregnant populations. MRSA vaginal colonization can lead to aerobic vaginitis (AV), and during pregnancy, bacterial ascension into the upper reproductive tract can lead to adverse birth outcomes. USA300, the most prominent MRSA lineage to colonize pregnant individuals, is a robust biofilm former and causative agent of invasive infections; however, little is known about how it colonizes and ascends in the female reproductive tract (FRT). Our previous studies showed that a MRSA mutant of seven fibrinogen-binding adhesins was deficient in FRT epithelial attachment and colonization. Using both monolayer and multilayer air-liquid interface cell culture models, we determine that one class of these adhesins, the fibronectin binding proteins (FnBPA and FnBPB), are critical for association with human vaginal epithelial cells (hVECs) and hVEC invasion through interactions with α5ß1 integrin. We observe that both FnBPs are important for biofilm formation as single and double fnbAB mutants exhibit reduced biofilm formation on hVECs. Using heterologous expression of fnbA and fnbB in Staphylococcus carnosus, FnBPs are also found to be sufficient for hVEC cellular association, invasion, and biofilm formation. In addition, we found that an ΔfnbAB mutant displays attenuated ascension in our murine vaginal colonization model. Better understanding of MRSA FRT colonization and ascension can ultimately inform treatment strategies to limit MRSA vaginal burden or prevent ascension, especially during pregnancy and in those prone to AV.

A type VII secretion system in Group B Streptococcus mediates cytotoxicity and virulence.

Type VII secretion systems (T7SS) have been identified in Actinobacteria and Firmicutes and have been shown to secrete effector proteins with functions in virulence, host toxicity, and/or interbacterial killing in a few genera. Bioinformatic analysis indicates that isolates of Group B Streptococcus (GBS) encode at least four distinct subtypes of T7SS machinery, three of which encode adjacent putative T7SS effectors with WXG and LXG motifs. However, the function of T7SS in GBS pathogenesis is unknown. Here we assessed the role of the most abundant GBS T7SS subtype during GBS pathogenesis. In a murine model of hematogenous meningitis, mice infected with GBS lacking a functional T7SS or lacking the secreted WXG100 effector EsxA exhibited less mortality, lower bacterial burdens in tissues, and decreased inflammation in the brain compared to mice infected with the parental GBS strain. We further showed that this T7SS induces cytotoxicity in brain endothelium and that EsxA contributes to these cytotoxicity phenotypes in a WXG motif-dependent manner. Finally, we determined that EsxA is a pore-forming protein, thus demonstrating the first role for a non-mycobacterial EsxA homolog in pore formation. This work reveals the importance of a T7SS in host-GBS interactions and has implications for T7SS effector function in other Gram-positive bacteria.

An Unconditional Cash Transfer Program for Low-Income New Yorkers Affected by COVID-19.

Early in the pandemic, New York City's public hospital system partnered with multiple philanthropic foundations to offer an unconditional cash transfer program for low-income New Yorkers affected by COVID-19. The $1000 cash transfers were designed to help people meet their most immediate health and social needs and were incorporated into healthcare delivery and contact tracing workflows as a response to the public health emergency. To better understand program recipients' experiences, researchers conducted 150 telephone surveys with randomly sampled cash transfer recipients and 20 in-depth qualitative interviews with purposefully sampled survey participants. Survey participants were predominantly Latinx (87%) and women (65%). The most common reported uses of the $1000 were food and rent. Most participants (79%) reported that without the $1000 cash transfer they would have had difficulty paying for basic expenses or making ends meet, with specific positive effects reported related to food, housing, and ability to work. The majority of survey participants reported that receiving the cash assistance somewhat or greatly improved their physical health (83%) and mental health (89%). Qualitative interview results generally supported the survey findings.

Peer Activate: A Feasibility Trial of a Peer-Delivered Intervention to Decrease Disparities in Substance Use, Depression, and Linkage to Substance Use Treatment.

Although effective evidence-based interventions (EBIs) exist, racial/ethnic minority individuals with lower income are less likely to have access to these interventions and may experience greater stigma in the health care system, resulting in disproportionate rates of morbidity and mortality. Peer recovery specialists (PRSs) may be uniquely suited to address barriers faced by those from impoverished areas; however, peers have not traditionally been trained in implementing EBIs. The current open-label trial (N = 8) was performed to evaluate implementation and preliminary effectiveness of an adapted EBI supporting recovery, linkage to treatment, and reduced depression. Results suggest the intervention was feasible, acceptable, and appropriate for linking individuals from a community setting to substance use treatment and could be delivered with fidelity by a peer interventionist. Participants who completed the intervention demonstrated clinically reliable decreases in substance use and depressive symptoms. Findings provide initial support for PRS dissemination of EBIs to increase linkage to care and support recovery in traditionally underserved populations. [Journal of Psychosocial Nursing and Mental Health Services, 61(11), 23-31.].

Working Memory Training Reduces Cigarette Smoking Among Low-Income Individuals With Elevated Delay Discounting.

INTRODUCTION: The competing neurobehavioral decision systems theory conceptualizes addictive behavior, such as cigarette smoking, as arising from the imbalance between stronger impulsive relative to weaker executive decision processes. Working memory trainings may enhance executive decision processes, yet few studies have evaluated its efficacy on substance misuse, with mixed evidence. The current study is the first to evaluate the efficacy of a working memory training on cigarette smoking. We consider the moderating role of delay discounting (DD), or the preference for smaller, immediately available rewards relative to larger, delayed rewards, which has been associated with smoking onset, progression, and resumption. The investigation focuses on individuals living in high-poverty, low-resource environments due high burden of tobacco-related disease they experience. AIMS AND METHODS: The study utilized a subset of data (N = 177 individuals who smoke) generated from a randomized clinical trial that is evaluating the efficacy of working memory training for improving health-related outcomes. Participants were randomized to complete up to 15 sessions of the active, working memory training or a control training. RESULTS: Findings showed that among participants who were randomized to the working memory condition, those with higher rates of baseline DD demonstrated decreases in cigarette smoking (p = .05). Conversely, individuals randomized to the control condition, who had higher rates of baseline DD exhibited increases in cigarette smoking (p = .025). CONCLUSIONS: Results suggest that DD may be an important indicator of working memory training outcomes and a possible approach for effectively targeting treatments in the future. IMPLICATIONS: DD is important indicator of working memory training outcomes on cigarette smoking. The findings suggest the possibility to effectively target treatments considering the impact of DD. Given that rates of DD tend to be higher among individuals from low-resource communities, and that computer-based working memory training programs are relatively low-cost and scalable, these findings suggest this approach may have specific utility for adults at heightened risk for cigarette use.This study was registered with ClinicalTrials.gov (Identifier NCT03501706).

Association of substance use characteristics and future homelessness among emergency department patients with drug use or unhealthy alcohol use: Results from a linked data longitudinal cohort analysis.

Background: Homelessness and substance use are intricately related, and both are prevalent among emergency department (ED) patients. This study examined the longitudinal association of substance use characteristics with future homeless shelter entry among ED patients with any drug use or unhealthy alcohol use. Methods: We present results from a longitudinal cohort study of public hospital ED patients who screened positive for drug use or unhealthy alcohol use and who were not homeless at their baseline (index) ED visit. The primary outcome was homeless shelter entry within 12 months of baseline, ascertained in city homeless shelter administrative data. Primary independent variables of interest were alcohol use severity (AUDIT), drug use severity (DAST-10), and types of drugs used, as reported on baseline survey questionnaires. Results: Analyses included 1,210 ED patients. By 12 months following the baseline ED visit, 114 (9.4%) had entered a homeless shelter. Among patients with the most severe problems related to drug use (DAST-10 score 9-10), 40.9% entered a shelter within 12 months. Past shelter use was the strongest predictor of future shelter entry; once adjusting for historic shelter use the relationship of AUDIT and DAST-10 scores with future shelter entry was no longer statistically significant in multivariable models. Conclusions: ED patients with past year drug use or unhealthy alcohol use had relatively high likelihood of future shelter entry. Risk for homelessness should be addressed in future interventions with this population. Findings illustrate the complexity of relationships between substance use and homelessness.

Social relationships, homelessness, and substance use among emergency department patients.

Background: Emergency department (ED) patients commonly experience both substance use and homelessness, and social relationships impact each in varied ways not fully captured by existing quantitative research. This qualitative study examines how social relationships can precipitate or ameliorate homelessness and the connection (if any) between substance use and social relationships among ED patients experiencing homelessness. Methods: As part of a broader study to develop ED-based homelessness prevention interventions, we conducted in-depth interviews with 25 ED patients who used alcohol or drugs and had recently become homeless. We asked patients about the relationship between their substance use and homelessness. Interviews were recorded, transcribed, and coded line-by-line by investigators. Final codes formed the basis for thematic analysis through consensus discussions. Results: Social relationships emerged as focal points for understanding the four major themes related to the intersection of homelessness and substance use: (1) Substance use can create strain in relationships; (2) Help is there until it's not; (3) Social relationships can create challenges contributing to substance use; and (4) Reciprocal relationship of substance use and isolation. Sub-themes were also identified and described. Conclusions: The association between substance use and homelessness is multifaceted and social relationships are a complex factor linking the two. Social relationships are often critical for homelessness prevention, but they are impacted by and reciprocally affect substance use. ED-based substance use interventions should consider the high prevalence of homelessness and the impact of social relationships on the interaction between homelessness and substance use.

Factors Influencing Long-Term Care Workers' Self-Efficacy for Encouraging Residents to Engage in Physical Activity.

We aimed to assess work-related factors and their association with long-term care workers' self-efficacy for encouraging and engaging residents in physical activity. Baseline data from a worksite wellness study with 98 workers were used. We used a linear regression model, to assess if job satisfaction, work ability, and social support for staff health behaviors from coworkers and supervisors were associated with staffs' self-efficacy for Function-Focused Care (FFC) and Staffs' Outcome Expectations for FFC. Staffs' social support for healthy behaviors from coworkers was the only factor that was significantly associated with Staffs' Outcome Expectations for FFC and staffs' self-efficacy-FFC, respectively explaining 19% and 14% of the variance. Our findings show that staffs' social support from coworkers is associated with higher self-efficacy for encouraging and engaging residents in physical activity suggests future worksite wellness studies with long-term care workers may wish to consider assessing program impacts on residents' physical activity levels.

Factors Associated With the Quality of Staff-Resident Interactions in Assisted Living.

BACKGROUND: Care interactions are verbal or nonverbal interactions between staff and residents during social or physical care activities. The quality of care interactions could be positive, negative, or neutral. PURPOSE: The purpose of this study was to examine the resident- and facility-level factors associated with the care interactions in assisted living (AL). METHODS: Regression analysis was performed using a stepwise method utilizing baseline data of 379 residents from 59 AL facilities recruited in a randomized trial. RESULTS: Accounting for 8.2% of variance, increased resident agitation was associated with negative or neutral quality interactions while for-profit ownership was associated with positive quality interactions. CONCLUSIONS: To promote positive care interactions, findings suggest the need to educate staff about strategies to minimize resident agitation (eg, calm posture and respectful listening) and work toward optimizing care interactions in nonprofit settings. Future research could further explore the influence of staff-level factors on care interactions.

Pilot Testing of the Promoting Positive Care Interactions Intervention in Assisted Living.

The current study aimed to test the feasibility and preliminary efficacy of the Promoting Positive Care Interactions (PPCI) intervention designed to establish positive care interactions between staff and residents in assisted living (AL) using an online approach. PPCI was implemented in one AL community using a single group pre-/posttest design; 17 care staff were recruited from the memory care unit. Delivery, receipt, and enactment of the PPCI were assessed for feasibility. Change in staff outcomes and facility outcomes were examined for preliminary efficacy. The four steps of the PPCI were implemented as intended with 100% staff exposure to education and considerable staff engagement in weekly mentoring sessions. Although there was an improvement in AL environment and policy, no significant changes were observed in staff outcomes. Future testing of the PPCI should include a longer timeline and explore a hybrid model that includes online education and in-person mentoring and coaching of staff to improve care interactions. [Journal of Gerontological Nursing, 48(8), 17-25.].

The Group B Streptococcal surface antigen I/II protein, BspC, interacts with host vimentin to promote adherence to brain endothelium and inflammation during the pathogenesis of meningitis.

Streptococcus agalactiae (Group B Streptococcus, GBS) normally colonizes healthy adults but can cause invasive disease, such as meningitis, in the newborn. To gain access to the central nervous system, GBS must interact with and penetrate brain or meningeal blood vessels; however, the exact mechanisms are still being elucidated. Here, we investigate the contribution of BspC, an antigen I/II family adhesin, to the pathogenesis of GBS meningitis. Disruption of the bspC gene reduced GBS adherence to human cerebral microvascular endothelial cells (hCMEC), while heterologous expression of BspC in non-adherent Lactococcus lactis conferred bacterial attachment. In a murine model of hematogenous meningitis, mice infected with ΔbspC mutants exhibited lower mortality as well as decreased brain bacterial counts and inflammatory infiltrate compared to mice infected with WT GBS strains. Further, BspC was both necessary and sufficient to induce neutrophil chemokine expression. We determined that BspC interacts with the host cytoskeleton component vimentin and confirmed this interaction using a bacterial two-hybrid assay, microscale thermophoresis, immunofluorescent staining, and imaging flow cytometry. Vimentin null mice were protected from WT GBS infection and also exhibited less inflammatory cytokine production in brain tissue. These results suggest that BspC and the vimentin interaction is critical for the pathogenesis of GBS meningitis.

Health-Related Social Needs Among Emergency Department Patients with HIV.

Little research has examined the health-related social needs of emergency department (ED) patients who have HIV. We surveyed a random sample of public hospital ED patients and compared the social needs of patients with and without HIV. Social needs were high among all ED patients, but patients with HIV reported significantly higher levels of food insecurity (65.0% vs. 50.3%, p = 0.01) and homelessness or living doubled up (33.8% vs. 21.0%, p < 0.01) than other patients. Our findings suggest the importance of assessing social needs in ED-based interventions for patients with HIV.

RESUMEN: Pocas investigaciones han examinado las necesidades sociales relacionadas con la salud de los pacientes del departamento de emergencias que tienen VIH. Encuestamos una muestra aleatoria de pacientes del departamento de emergencias de un hospital público y comparamos las necesidades sociales de los pacientes con y sin VIH. Las necesidades sociales eran altas entre todos los pacientes, pero los pacientes con VIH informaron niveles significativamente más altos de inseguridad alimentaria (65.0% vs. 50.3%, p = 0.01) y estado sin hogar o compartir una habitación (33.8% vs. 21.0%, p < 0.01) que otros pacientes. Nuestros resultados sugieren la importancia de evaluar las necesidades sociales en las intervenciones en departamentos de emergencias para pacientes con VIH.

Determinants of intergenerational sexual relationships and HIV risk among South African women outpatients in Gauteng.

Age-discrepant sexual relationships may place women at risk for HIV infection in South Africa. Results are based on medical records and case-control interview data of 889 sexually experienced women outpatients aged 15-29 in a Gauteng township. Women with partners at least ten years older (intergenerational) show an elevated chance of having an early sexual debut, concurrent and transactional partners, and intimate partner violence. Hardship during childhood including parental loss, food insecurity and abuse are related to age asymmetric relationships. HIV is two times more likely (aOR=1.96) with an intergenerational partner. Transactional sex increases the odds of HIV independently (aOR=1.76) as does intimate partner violence (aOR=1.6). To the extent that transactional and intergenerational sex overlap the chance of contracting HIV increases more than two-fold (uOR=4.57). Girls (15-19) with intergenerational partners face the highest chance of HIV (uOR=8.55) compared to other age groups. They are also five times more likely than controls to have lived with a cross-age partner. Our findings indicate there are multiple pathways emanating from childhood leading to women's choice of intergenerational partners, and the link to HIV is strongest among the youngest women.

The Joint Effect of Childhood Abuse and Homelessness on Substance Use in Adulthood.

BACKGROUND: Childhood abuse and homelessness are independently associated with substance use. Though childhood abuse and homelessness are strongly correlated, research on the joint effect of exposure to both traumatic life events on substance use is limited. Objective: To estimate independent and joint effects of childhood abuse and homelessness on substance use risk during emerging adulthood and adulthood. Methods: Using the National Longitudinal Study of Adolescent to Adult Health (N = 12,288), we measured associations between exposure to physical or sexual abuse in childhood, homelessness in childhood or emerging adulthood, or exposure to both traumas and outcomes of binge drinking, marijuana use, cocaine use, methamphetamine use, and prescription opioid misuse during emerging adulthood (Wave III, ages 18-26 years) and adulthood (Wave IV, ages 24-32 years). Results: In adjusted analyses, exposure to childhood abuse alone, homelessness alone, and both childhood abuse and homelessness were significant correlates of most substance use indicators in emerging adulthood. Those jointly exposed to childhood abuse and homelessness had disproportionate risk of substance use, particularly use of cocaine (adjusted odds ratio (AOR)=4.25, 95% confidence interval (CI): 2.70, 6.71) and methamphetamine (AOR = 6.59, 95% CI: 3.87, 11.21). The independent and combined effects of abuse and homelessness generally persisted into adulthood though associations tended to weaken. Conclusions/Importance: Those with exposure to abuse, homelessness, and both adverse outcomes constitute a high-risk population for substance use. Addressing abuse and homelessness should be a component of preventing drug risk for screening, treatment, and prevention efforts.