Transient hypoxia drives soil microbial community dynamics and biogeochemistry during human decomposition.

Human decomposition in terrestrial ecosystems is a dynamic process creating localized hot spots of soil microbial activity. Longer-term (beyond a few months) impacts on decomposer microbial communities are poorly characterized and do not typically connect microbial communities to biogeochemistry, limiting our understanding of decomposer communities and their functions. We performed separate year-long human decomposition trials, one starting in spring, another in winter, integrating bacterial and fungal community structure and abundances with soil physicochemistry and biogeochemistry to identify key drivers of microbial community change. In both trials, soil acidification, elevated microbial respiration, and reduced soil oxygen concentrations occurred. Changes in soil oxygen concentrations were the primary driver of microbial succession and nitrogen transformation patterns, while fungal community diversity and abundance was related to soil pH. Relative abundance of facultative anaerobic taxa (Firmicutes and Saccharomycetes) increased during the period of reduced soil oxygen. The magnitude and timing of the decomposition responses were amplified during the spring trial relative to the winter, even when corrected for thermal inputs (accumulated degree days). Further, soil chemical parameters, microbial community structure, and fungal gene abundances remained altered at the end of 1 year, suggesting longer-term impacts on soil ecosystems beyond the initial pulse of decomposition products.

A non-canonical CDK, Pho85 regulates the restart of the cell-cycle following stress.

Environmental stress induces an arrest of the cell cycle. Thus, release from this arrest is essential for cell survival. The cell-cycle-arrest occurs via the down regulation of the cyclins that drive the main cyclin dependent kinase, CDK1/Cdc28. However, it was not clear how cells escape this potentially fatal arrest. Here we show that prior to the restoration of CDK1/Cdc28 cyclins, a non-canonical CDK, Pho85, initiates a cascade to restart the cell cycle. We demonstrate that following stress, Pho85 phosphorylates the Sch9 kinase, which in turn directly phosphorylates the transcriptional inhibitor Whi5, the yeast analog of RB1/retinoblastoma, and a CDK1 target. This promotes Whi5 translocation from the nucleus, and the release of the stress-induced arrest at G 1 phase. In addition, we find that in parallel with Pho85, CDK1/Cdc28 also plays a role in the control of Whi5. Together, these findings provide insights into how cells re-enter the cell cycle during recovery from stress and reveal that a non-canonical CDK and cyclin takes on essential roles and acts via a pathway that functions in parallel with CDK1/Cdc28.

Parvalbumin gates chronic pain through the modulation of firing patterns in inhibitory neurons.

Spinal cord dorsal horn inhibition is critical to the processing of sensory inputs, and its impairment leads to mechanical allodynia. How this decreased inhibition occurs and whether its restoration alleviates allodynic pain are poorly understood. Here, we show that a critical step in the loss of inhibitory tone is the change in the firing pattern of inhibitory parvalbumin (PV)-expressing neurons (PVNs). Our results show that PV, a calcium-binding protein, controls the firing activity of PVNs by enabling them to sustain high-frequency tonic firing patterns. Upon nerve injury, PVNs transition to adaptive firing and decrease their PV expression. Interestingly, decreased PV is necessary and sufficient for the development of mechanical allodynia and the transition of PVNs to adaptive firing. This transition of the firing pattern is due to the recruitment of calcium-activated potassium (SK) channels, and blocking them during chronic pain restores normal tonic firing and alleviates chronic pain. Our findings indicate that PV is essential for controlling the firing pattern of PVNs and for preventing allodynia. Developing approaches to manipulate these mechanisms may lead to different strategies for chronic pain relief.

ElecFeX is a user-friendly toolbox for efficient feature extraction from single-cell electrophysiological recordings.

Characterizing neurons by their electrophysiological phenotypes is essential for understanding the neural basis of behavioral and cognitive functions. Technological developments have enabled the collection of hundreds of neural recordings; this calls for new tools capable of performing feature extraction efficiently. To address the urgent need for a powerful and accessible tool, we developed ElecFeX, an open-source MATLAB-based toolbox that (1) has an intuitive graphical user interface, (2) provides customizable measurements for a wide range of electrophysiological features, (3) processes large-size datasets effortlessly via batch analysis, and (4) yields formatted output for further analysis. We implemented ElecFeX on a diverse set of neural recordings; demonstrated its functionality, versatility, and efficiency in capturing electrical features; and established its significance in distinguishing neuronal subgroups across brain regions and species. ElecFeX is thus presented as a user-friendly toolbox to benefit the neuroscience community by minimizing the time required for extracting features from their electrophysiological datasets.

The CARING study: Examining biological, behavioral, and genetic mechanisms in the intergenerational transmission of toxic stress.

When children experience extreme or persistent stressors (e.g., maltreatment, housing insecurity, intimate partner violence), prolonged elevation of the stress-response system can lead to disrupted development of multiple physiological systems. This response, known as toxic stress, is associated with poor physical and mental health across the life course. Emerging evidence suggests that the effects of toxic stress may be transmitted through generations, but the biological and behavioral mechanisms that link caregivers' childhood history with the health of the children they care for remain poorly understood. The purpose of this report is to describe the research protocol for The CARING (Childhood Adversity and Resilience In the Next Generation) Study, a cross-sectional study of caregivers with children aged 3-5 years designed to (1) examine the intergenerational transmission of toxic stress and protective factors; (2) explore three hypothesized pathways of transmission: parenting, daily routines, stressors, and supports; and (3) explore the extent to which genotypic variation in candidate genes related to caregiving and stress contribute to caregivers' and children's susceptibility to the effects of early childhood experiences (i.e., gene × environment interactions). We expect that findings from this study will provide critical data needed to identify targets for precision health interventions, reduce health disparities related to toxic stress, and prevent cycles of adversity among families at risk.

Parenting experiences and outcomes among former adolescent mothers: A mixed methods study.

The purpose of this explanatory sequential mixed methods study was to examine parenting outcomes and experiences over time among marginalized adolescent mothers enrolled in randomized clinical trials (RCT) between 2002 and 2016 testing Minding the Baby® (MTB), an early home visiting program. The quantitative phase examined associations between measures of maternal experiences and parenting outcomes from 71 participants 2-8 years since RCT completion. MTB mothers reported less hostile parenting and fewer child behavior problems. The sequential qualitative phase involved interviews with a subsample (n = 31) and revealed six themes about their personal and parenting maturation. Through integration of quantitative and qualitative data, we generated metainferences, revealing a nuanced understanding of participants' experiences. Integrated findings revealed the complex personal and parenting experiences among former adolescent mothers during their developmental phases of emerging and early adulthood. Findings inform clinical and research approaches to promote personal growth and positive parenting outcomes over time among women who began childbearing in adolescence.

Experiences of Stigma and Discrimination Compounded by Intersecting Identities among Individuals Receiving Medication for Opioid Use Disorder.

Stigma and discrimination create barriers to care among people receiving medication for opioid use disorder (MOUD). We report qualitative findings from a mixed methods study guided by three aims: to explore (1) intersecting identities of people receiving MOUD (2) how individuals experience stigma and discrimination and (3) helpful resources in addressing cumulative experiences of multiple forms of disadvantage. We conducted interviews with 25 individuals in three treatment centers in the Northeast United States and identified six themes: (1) Living with multiple socially marginalized identities and addiction; (2) Loss; (3) "It's everywhere": Discrimination and stigma; (4) A "damaged" identity, (5) Positive responses to negative experiences: Facing reality and becoming accountable, and (6) Experiencing treatment and identifying supportive interventions. Findings highlight the complexity of intersecting, marginalized social positions. Future work should look beyond one-size-fits-all approaches to care and recognize individual vulnerabilities and strengths for improving outcomes among those experiencing OUD.

Investigating the role of nicotinic acetylcholine receptors in menthol's effects in mice.

The use of menthol in tobacco products has been linked to an increased likelihood of developing nicotine dependence. The widespread use of menthol can be attributed to its unique sensory characteristics; however, emerging evidence suggests that menthol also alters sensitivity to nicotine through modulation of nicotinic acetylcholine receptors (nAChRs). Nicotinic subunits, such as ß2 and α5, are of interest due to their implications in nicotine reward, reinforcement, intake regulation, and aversion. This study, therefore, examined the in vivo relevance of ß2 and α5 nicotinic subunits on the pharmacological and behavioral effects of menthol. Data suggests that the α5 nicotinic subunit modulates menthol intake in mice. Overall, deletion or a reduction in function of the α5 subunit lessened aversion to menthol. α5 KO mice and mice possessing the humanized α5 SNP, a variant that confers a nicotine dependence phenotype in humans, demonstrated increased menthol intake compared to their WT counterparts and in a sex-related fashion for α5 SNP mice. We further reported that the modulatory effects of the α5 subunit do not extend to other aversive tastants like quinine, suggesting that deficits in α5* nAChR signaling may not abolish general sensitivity to the aversive effects of other noxious chemicals. Further probing into the role of α5 in other pharmacological properties of menthol revealed that the α5 subunit does not modulate the antinociceptive properties of menthol in mice and suggests that the in vivo differences observed are likely not due to the direct effects of menthol on α5-containing nAChRs in vitro.

"It's all connected:" A mixed methods study of insomnia, stigma, and discrimination among individuals on medication for opioid use disorder.

OBJECTIVES: Insomnia is one of the most common sleep disorders among those with opioid use disorder (OUD), including those on medication for OUD. There is a dearth of literature exploring the role of social stressors on sleep outcomes among this group. The purpose of this study was to explore the association between OUD-related stigma and intersectional discrimination with insomnia among individuals on medication for OUD. METHODS: Participants were recruited from treatment clinics in the Northeast United States. Using a convergent mixed-methods research design, we explored associations with stigma (The Brief Opioid Stigma Scale), intersectional discrimination (Intersectional Discrimination Index), and insomnia (Insomnia Severity Index) through quantitative survey data and qualitative data from interviews for participant experiences. Data from the quantitative (n = 120) and qualitative (n = 25) components of the study were integrated for interpretation. RESULTS: Quantitative analysis indicated weak to moderate positive correlations between intersectional discrimination, and exploratory variables including pain, perceived stress, and psychological distress with insomnia severity. The qualitative analysis generated 4 main themes, which highlighted negative emotions and ruminations as factors that participants connected experiences with stigma and discrimination to poor sleep outcomes. Integration of data identified concordant and discordant findings. CONCLUSIONS: Stigma, discrimination, physical symptoms, and psychological distress appear to contribute to poor sleep outcomes among those with OUD. Future research should target maladaptive outcomes of rumination and negative emotions to improve sleep outcomes among those with OUD.

A signaling lipid drives synapse formation.

Phosphatidylinositol 3,5-bisphosphate enables transport of proteins to synaptic sites.

Modulation of SK Channels via Calcium Buffering Tunes Intrinsic Excitability of Parvalbumin Interneurons in Neuropathic Pain: A Computational and Experimental Investigation.

Parvalbumin-expressing interneurons (PVINs) play a crucial role within the dorsal horn of the spinal cord by preventing touch inputs from activating pain circuits. In both male and female mice, nerve injury decreases PVINs' output via mechanisms that are not fully understood. In this study, we show that PVINs from nerve-injured male mice change their firing pattern from tonic to adaptive. To examine the ionic mechanisms responsible for this decreased output, we used a reparametrized Hodgkin-Huxley type model of PVINs, which predicted (1) the firing pattern transition is because of an increased contribution of small conductance calcium-activated potassium (SK) channels, enabled by (2) impairment in intracellular calcium buffering systems. Analyzing the dynamics of the Hodgkin-Huxley type model further demonstrated that a generalized Hopf bifurcation differentiates the two types of state transitions observed in the transient firing of PVINs. Importantly, this predicted mechanism holds true when we embed the PVIN model within the neuronal circuit model of the spinal dorsal horn. To experimentally validate this hypothesized mechanism, we used pharmacological modulators of SK channels and demonstrated that (1) tonic firing PVINs from naive male mice become adaptive when exposed to an SK channel activator, and (2) adapting PVINs from nerve-injured male mice return to tonic firing on SK channel blockade. Our work provides important insights into the cellular mechanism underlying the decreased output of PVINs in the spinal dorsal horn after nerve injury and highlights potential pharmacological targets for new and effective treatment approaches to neuropathic pain.SIGNIFICANCE STATEMENT Parvalbumin-expressing interneurons (PVINs) exert crucial inhibitory control over Aß fiber-mediated nociceptive pathways at the spinal dorsal horn. The loss of their inhibitory tone leads to neuropathic symptoms, such as mechanical allodynia, via mechanisms that are not fully understood. This study identifies the reduced intrinsic excitability of PVINs as a potential cause for their decreased inhibitory output in nerve-injured condition. Combining computational and experimental approaches, we predict a calcium-dependent mechanism that modulates PVINs' electrical activity following nerve injury: a depletion of cytosolic calcium buffer allows for the rapid accumulation of intracellular calcium through the active membranes, which in turn potentiates SK channels and impedes spike generation. Our results therefore pinpoint SK channels as potential therapeutic targets for treating neuropathic symptoms.

Early emergence of racial and ethnic differences in sleep health among toddlers living in low-income families.

OBJECTIVES: Emerging evidence suggests racial and ethnic and socioeconomic differences in children's sleep health, yet few have examined these differences among very young children. The purpose of this study is to identify potential racial, ethnic, and sociodeomographic factors associated with multiple dimensions of sleep health in toddlers living in very low-income families. PARTICIPANTS: Sample included 110 racially and ethnically diverse dyads with toddlers aged 12-15 months living in low-income families. METHODS: Actigraph data (9 days and nights), caregiver completed sleep diaries, Brief Infant Sleep Questionnaire-extended, and caregiver-reported socioeconomic characteristics were collected. RESULTS: Toddlers' average sleep duration (10.25 hours; SD = 0.76) was less than the age-based recommendations. There were significant race and ethnic differences in toddler's actigraph-measured bedtime (p < .001) and variability in bedtimes (p = .004). Non-LatinX White toddlers had earlier bedtimes and less variability than Black and LatinX children. These between-group differences remained statistically significant after controlling for measured socioeconomic variables (p's < 0.001). Within racial and ethnic group differences in bedtime and bedtime variability by education, employment, and marital status were identified with medium to large effect sizes. CONCLUSIONS: Racial and ethnic between-group differences in sleep occurred as early as 12 months of age and were not explained by sociodemographic variables (eg, income-to-needs, education, housing). Further research is necessary to determine structural and contextual factors that explain the racial and ethnic differences in sleep health in early childhood. Identifying these factors may inform the development of socially and culturally tailored interventions to reduce sleep health disparities.

Something Has to Give: An Urban Community-Engaged Focus Group Study of Teen Sleep.

Sleep is critical to teen physical and mental health, daily function, and school performance. Yet, sleep deficiency is prevalent among ethnoracially diverse teens. The purpose of this community-engaged focus group study was to explore multilevel influences on teen sleep from teen and community stakeholder perspectives and to use this information to develop a tailored sleep health intervention. We conducted seven focus groups (N = 46) and analyzed data via content analysis. Five themes, each with subthemes, described sleep knowledge/attitudes, sleep habits, the multilevel causes and consequences of decreased nighttime sleep and suggestions for improving teen sleep. Teen health, mood, and school engagement were all impacted by inadequate nighttime sleep. Exhaustion emerged as an overarching theme and coincided with the transition to high school. The data from this study provide insight into important areas of focus for a sleep intervention tailored to the needs of ethnoracially diverse teens living in an urban community.

Virtual interviewing with marginalized young adult mothers: appreciating the New Norm.

BACKGROUND AND OBJECTIVE: Virtual interviewing in qualitative research may promote inclusion, diversify samples, and maximize participation, but there is limited research regarding methodological best practices for marginalized study populations. Emerging adult (ages 18-29) and young adult (through age 40) mothers have ongoing stressors and competing responsibilities that may preclude participation with in-person interviews. The purpose of this article is to describe the processes and experiences of virtual interviewing among young adult mothers living in under-resourced communities, based on their responses to specific interview questions. DESIGN AND SAMPLE: As part of an explanatory sequential mixed methods study, qualitative interviews were conducted with a sample of young adult mothers who had previously participated in randomized controlled trials testing an intensive early home visiting intervention. Thirty-one participants (M = 29.7 years, SD = 2.5) who identified as Black (39%), Hispanic (55%), and White (7%), were interviewed using Zoom. RESULTS: The overarching theme was Zoom: Appreciating the New Norm. Identified categories were Practical Benefits of Virtual Interviewing, Sharing Stories, and Drawbacks of Virtual Interviewing. CONCLUSION: Findings support virtual interviewing as a feasible and potentially ideal method for qualitative studies with emerging/young adults. Further research to examine this approach with other marginalized populations may lead to more inclusive representation in qualitative research.

Soil elemental changes during human decomposition.

Mammalian decomposition provides pulses of organic matter to the local ecosystem creating ephemeral hotspots of nutrient cycling. While changes to soil biogeochemistry in these hotspots have been described for C and N, patterns associated with deposition and cycling of other elements have not received the same attention. The goal of our study was to evaluate temporal changes to a broad suite of dissolved elements in soils impacted by human decomposition on the soil surface including: 1) abundant mineral elements in the human body (K, Na, S, P, Ca, and Mg), 2) trace elements in the human body (Fe, Mn, Se, Zn, Cu, Co, and B), and 3) Al which is transient in the human body but common in soils. We performed a four-month human decomposition trial at the University of Tennessee Anthropology Research Facility and quantified elemental concentrations dissolved in the soil solution, targeting the mobile and bioavailable fraction. We identified three groups of elements based on their temporal patterns. Group 1 elements appeared to be cadaver-derived (Na, K, P, S) and their persistence in soil varied based upon soluble organic forms (P), the dynamics of the soil exchange complex (Na, K), and gradual releases attributable to microbial degradation (S). Group 2 elements (Ca, Mg, Mn, Se, B) included three elements that have greater concentrations in soil than would be expected based on cadaver inputs alone, suggesting that these elements partially originate from the soil exchange (Ca, Mg), or are solubilized as a result of soil acidification (Mn). Group 3 elements (Fe, Cu, Zn, Co, Al) increased late in the decomposition process, suggesting a gradual solubilization from soil minerals under acidic pH conditions. This work presents a detailed longitudinal characterization of changes in dissolved soil elements during human decomposition furthering our understanding of elemental deposition and cycling in these environments.

Participation in an Attachment-Based Home Visiting Program Is Associated with Lower Child Salivary C-Reactive Protein Levels at Follow-Up.

OBJECTIVE: Exposure to early childhood adversity is associated with an increased risk for physiological disruption, including increased inflammation. Early interventions that support the mother-child relationship have been shown to potentially buffer negative psychosocial outcomes related to early adversity, but it is unclear whether these interventions have long-term biological effects. We evaluated whether prior participation in Minding the Baby® (MTB), an attachment-based home visiting intervention for young mother-infant dyads living in underserved communities, is associated with lower child salivary inflammatory biomarkers compared with controls at follow-up. METHODS: Ninety-seven maternal-child dyads (n = 43 intervention and n = 54 controls) enrolled in a follow-up study of the MTB randomized controlled trial, an average of 4.6 years after RCT completion. Children provided salivary specimens. We used adjusted linear regression to examine the relationship between MTB participation and child salivary inflammatory biomarkers (C-reactive protein [CRP], interleukin [IL]-1ß, IL-6, IL-8, and TNF-α). RESULTS: Children were on average 6.6 years old, 48% female, and identified as non-Hispanic/Latino Black/African American (34%) and Hispanic/Latino (63%). Participation in MTB was associated with lower salivary CRP levels (ß = -0.31, SE = 0.28, p = 0.003) compared with controls. Participation in MTB was not associated with salivary cytokine levels. DISCUSSION: Participation in an intensive two-generation home visiting intervention such as MTB may reduce salivary inflammatory biomarkers associated with early childhood adversity. Replication and further research are needed to improve the understanding of the potential for early childhood interventions to buffer the biological embedding of early adversity.

"Here I Don't Feel Like a Stranger": Adolescents' Perspectives on School-Based Health Centers.

This study explored adolescent perspectives on school-based health center (SBHC) services and how services differed from school nurses and community agencies. Six focus groups were conducted with adolescents, 13-19 years old, as part of a larger mixed-methods study. Data were analyzed for themes using content analysis. Adolescents (N = 30) described the accessibility, positive attitude of staff, competence of the nurse practitioner, confidentiality/privacy, and trusted relationships with staff as important aspects of SBHC care. SBHC services allowed adolescents to stay in school, provided confidentiality/privacy, were comfortable and convenient, fostered their independence, and adolescents felt SBHC staff knew them and they did not feel like strangers. SBHCs are adolescent-friendly resources that maximize school time and an important source for contraception, sexually transmitted infection testing, and mental health care. Additionally, SBHC services help support adolescents' transition from pediatric to adolescent-focused care and foster their growing self-awareness and empowerment related to their engagement in health care services.

Recruitment of the SNX17-Retriever recycling pathway regulates synaptic function and plasticity.

Trafficking of cell-surface proteins from endosomes to the plasma membrane is a key mechanism to regulate synaptic function. In non-neuronal cells, proteins recycle to the plasma membrane either via the SNX27-Retromer-WASH pathway or via the recently discovered SNX17-Retriever-CCC-WASH pathway. While SNX27 is responsible for the recycling of key neuronal receptors, the roles of SNX17 in neurons are less understood. Here, using cultured hippocampal neurons, we demonstrate that the SNX17 pathway regulates synaptic function and plasticity. Disruption of this pathway results in a loss of excitatory synapses and prevents structural plasticity during chemical long-term potentiation (cLTP). cLTP drives SNX17 recruitment to synapses, where its roles are in part mediated by regulating the surface expression of ß1-integrin. SNX17 recruitment relies on NMDAR activation, CaMKII signaling, and requires binding to the Retriever and PI(3)P. Together, these findings provide molecular insights into the regulation of SNX17 at synapses and define key roles for SNX17 in synaptic maintenance and in regulating enduring forms of synaptic plasticity.

Upregulation of the ESCRT pathway and multivesicular bodies accelerates degradation of proteins associated with neurodegeneration.

Many neurodegenerative diseases, including Huntington's disease (HD) and Alzheimer's disease (AD), occur due to an accumulation of aggregation-prone proteins, which results in neuronal death. Studies in animal and cell models show that reducing the levels of these proteins mitigates disease phenotypes. We previously reported a small molecule, NCT-504, which reduces cellular levels of mutant huntingtin (mHTT) in patient fibroblasts as well as mouse striatal and cortical neurons from an HdhQ111 mutant mouse. Here, we show that NCT-504 has a broader potential, and in addition reduces levels of Tau, a protein associated with Alzheimer's disease, as well as other tauopathies. We find that in untreated cells, Tau and mHTT are degraded via autophagy. Notably, treatment with NCT-504 diverts these proteins to multivesicular bodies (MVB) and the ESCRT pathway. Specifically, NCT-504 causes a proliferation of endolysosomal organelles including MVB, and an enhanced association of mHTT and Tau with endosomes and MVB. Importantly, depletion of proteins that act late in the ESCRT pathway blocked NCT-504 dependent degradation of Tau. Moreover, NCT-504-mediated degradation of Tau occurred in cells where Atg7 is depleted, which indicates that this pathway is independent of canonical autophagy. Together, these studies reveal that upregulation of traffic through an ESCRT-dependent MVB pathway may provide a therapeutic approach for neurodegenerative diseases.