Slow phosphorylation of a tyrosine residue in LAT optimizes T cell ligand discrimination.

Self-non-self discrimination is central to T cell-mediated immunity. The kinetic proofreading model can explain T cell antigen receptor (TCR) ligand discrimination; however, the rate-limiting steps have not been identified. Here, we show that tyrosine phosphorylation of the T cell adapter protein LAT at position Y132 is a critical kinetic bottleneck for ligand discrimination. LAT phosphorylation at Y132, mediated by the kinase ZAP-70, leads to the recruitment and activation of phospholipase C-γ1 (PLC-γ1), an important effector molecule for T cell activation. The slow phosphorylation of Y132, relative to other phosphosites on LAT, is governed by a preceding glycine residue (G131) but can be accelerated by substituting this glycine with aspartate or glutamate. Acceleration of Y132 phosphorylation increases the speed and magnitude of PLC-γ1 activation and enhances T cell sensitivity to weaker stimuli, including weak agonists and self-peptides. These observations suggest that the slow phosphorylation of Y132 acts as a proofreading step to facilitate T cell ligand discrimination.

Near-equilibrium glycolysis supports metabolic homeostasis and energy yield.

Glycolysis plays a central role in producing ATP and biomass. Its control principles, however, remain incompletely understood. Here, we develop a method that combines 2H and 13C tracers to determine glycolytic thermodynamics. Using this method, we show that, in conditions and organisms with relatively slow fluxes, multiple steps in glycolysis are near to equilibrium, reflecting spare enzyme capacity. In Escherichia coli, nitrogen or phosphorus upshift rapidly increases the thermodynamic driving force, deploying the spare enzyme capacity to increase flux. Similarly, respiration inhibition in mammalian cells rapidly increases both glycolytic flux and the thermodynamic driving force. The thermodynamic shift allows flux to increase with only small metabolite concentration changes. Finally, we find that the cellulose-degrading anaerobe Clostridium cellulolyticum exhibits slow, near-equilibrium glycolysis due to the use of pyrophosphate rather than ATP for fructose-bisphosphate production, resulting in enhanced per-glucose ATP yield. Thus, near-equilibrium steps of glycolysis promote both rapid flux adaptation and energy efficiency.

Metabolite concentrations, fluxes and free energies imply efficient enzyme usage.

In metabolism, available free energy is limited and must be divided across pathway steps to maintain a negative ΔG throughout. For each reaction, ΔG is log proportional both to a concentration ratio (reaction quotient to equilibrium constant) and to a flux ratio (backward to forward flux). Here we use isotope labeling to measure absolute metabolite concentrations and fluxes in Escherichia coli, yeast and a mammalian cell line. We then integrate this information to obtain a unified set of concentrations and ΔG for each organism. In glycolysis, we find that free energy is partitioned so as to mitigate unproductive backward fluxes associated with ΔG near zero. Across metabolism, we observe that absolute metabolite concentrations and ΔG are substantially conserved and that most substrate (but not inhibitor) concentrations exceed the associated enzyme binding site dissociation constant (Km or Ki). The observed conservation of metabolite concentrations is consistent with an evolutionary drive to utilize enzymes efficiently given thermodynamic and osmotic constraints.

Complex care and contradictions of choice in the safety net.

This article explores the complicated and often-contradictory notions of choice at play in complex care management (CCM) programmes in the US healthcare safety net. Drawing from longitudinal data collected over two years of ethnographic fieldwork at urban safety-net clinics, our study examines the CCM goal of transforming frequent emergency department (ED) utilisers into 'active' patients who will reduce their service utilisation and thereby contribute to a more rational, cost-effective healthcare system. By considering our data alongside philosopher Annemarie Mol's (2008) conceptualisation of the competing logics of choice and care, we argue that these premises often undermine CCM teams' efforts to support patients and provide the care they need - not only to prevent medical crises, but to overcome socio-economic barriers as well. We assert that while safety-net CCM programmes are held accountable for the degree to which their patients successfully transform into self-managing, cost-effective actors, much of the care CCM staff provide in fact involves attempts to intervene on structural obstacles that impinge on patient choice. CCM programmes thus struggle between an economic imperative to get patients to make better health choices and a moral imperative to provide care in the face of systemic societal neglect. (A virtual abstract of this paper can be viewed at: https://www.youtube.com/channel/UC_979cmCmR9rLrKuD7z0ycA).

Effectiveness of mHealth behavior change communication interventions in developing countries: a systematic review of the literature.

Mobile health (mHealth) technologies and telecommunication have rapidly been integrated into the health care delivery system, particularly in developing countries. Resources have been allocated to developing mHealth interventions, including those that use mobile technology for behavior change communication (BCC). Although the majority of mobile phone users worldwide live in the developing world, most research evaluating BCC mHealth interventions has taken place in developed countries. The purpose of this study was to conduct a systematic review of the literature to determine how much evidence currently exists for mHealth BCC interventions. In addition to analyzing available research for methodological rigor and strength of evidence, the authors assessed interventions for quality, applying a set of 9 standards recommended by mHealth experts. The authors reviewed 44 articles; 16 (36%) reported evaluation data from BCC mHealth interventions in a developing country. The majority of BCC mHealth interventions were implemented in Africa (n = 10) and Asia (n = 4). HIV/AIDS (n = 10) and family planning/pregnancy (n = 4) were the health topics most frequently addressed by interventions. Studies did not consistently demonstrate significant effects of exposure to BCC mHealth interventions on the intended audience. The majority of publications (n = 12) described interventions that used two-way communication in their message delivery design. Although most publications described interventions that conducted formative research about the intended audience (n = 10), less than half (n = 6) described targeting or tailoring the content. Although mHealth is viewed as a promising tool with the ability to foster behavior change, more evaluations of current interventions need to be conducted to establish stronger evidence.

Single-cell analyses reveal early thymic progenitors and pre-B cells in zebrafish.

The zebrafish has proven to be a valuable model organism for studying hematopoiesis, but relatively little is known about zebrafish immune cell development and functional diversity. Elucidating key aspects of zebrafish lymphocyte development and exploring the breadth of effector functions would provide valuable insight into the evolution of adaptive immunity. We performed single-cell RNA sequencing on ∼70,000 cells from the zebrafish marrow and thymus to establish a gene expression map of zebrafish immune cell development. We uncovered rich cellular diversity in the juvenile and adult zebrafish thymus, elucidated B- and T-cell developmental trajectories, and transcriptionally characterized subsets of hematopoietic stem and progenitor cells and early thymic progenitors. Our analysis permitted the identification of two dendritic-like cell populations and provided evidence in support of the existence of a pre-B cell state. Our results provide critical insights into the landscape of zebrafish immunology and offer a foundation for cellular and genetic studies.

Ongoing tobacco use in women who experience homelessness and unstable housing: A prospective study to inform tobacco cessation interventions and policies.

BACKGROUND: Tobacco use is common in people who experience homelessness. However, despite biological differences in use by sex and lower quit rates in women, research in homeless and unstably housed (HUH) women is sparse. We identified correlates of use specific to this population, with the goal of informing tobacco cessation programs tailored for HUH women. METHODS: We conducted a prospective study among HUH women recruited from San Francisco homeless shelters, street encampments, free meal programs and low-income hotels. Between June 2016 and January 2019, study participants completed six monthly interviews to examine factors associated with tobacco use, defined as urinary cotinine >10 pg/mL or self-reported prior 30-day use. RESULTS: Among 245 participants, 40% were Black, the median age was 53, 75% currently used tobacco and 89% had ≥one 24-hour quit attempt in the prior year. Tobacco use was more common in women with PTSD (66% vs. 48%) and depression (54% vs. 35%) compared to women without these conditions. Adjusted odds of tobacco use decreased significantly with increasing age (OR/5 yrs: 0.81; 95% CI:0.68, 0.96) and increased with an increasing number of additional substances used (OR: 2.52; 95% CI: 1.88, 3.39). CONCLUSION: Outside of a treatment setting and within a community-recruited sample population composed of HUH women, the number of additional substances used is a primary correlate of ongoing tobacco use. Tailored cessation interventions that prioritize the issue of multiple substance use, and public health policies that allocate funding to address it, may increase tobacco cessation in this population.

Homeless women's perspectives on smoking and smoking cessation programs: A qualitative study.

BACKGROUND: Individuals who are unsheltered or experiencing homelessness are more likely to smoke than those in the general population and have a higher prevalence of tobacco-related illnesses. Those who are unhoused make quit attempts at rates similar to the general population, however rates of successful quitting are much lower. Women bear a higher burden of smoking-related diseases and are less successful in their cessation efforts than men. Despite these increased risks and challenges, cessation programs specifically designed to meet the needs of women experiencing homelessness are extremely rare. METHODS: To examine perceptions of smoking cessation programs among women who are unstably housed, we conducted in-depth, semi-structured interviews with twenty-nine women experiencing homelessness or unstable housing who had histories of tobacco and substance use. Interviews explored the social context of smoking, as well as interest in, barriers to, and facilitators of quitting. We used a grounded theory approach to analyze the transcripts. RESULTS: Participants reported a number of structural barriers to cessation. They reported obstacles to participating in existing cessation programs, including chronic stress related to experiences of being unsheltered and fear of being exposed to neighborhood violence. These conditions were paired with a strong need to self-isolate in order to maintain personal safety, which runs counter to traditional group-based cessation programs. CONCLUSION: A dissonance exists between current smoking cessation programs and the needs of women who are unsheltered or unstably housed. Alternative cessation treatment delivery models that address extremely high levels of chronic stress violence, and avoidance of group settings are needed, as are programs that provide options for safe participation.

A crack in the wall: Chronic pain management in integrative group medical visits.

Amidst a national crisis of opioid overdose, substantial uncertainty remains over how to safely and effectively address chronic pain. In response to this crisis, safety-net primary care clinics are instituting integrative group medical visits (IGMVs) for chronic pain management. Through two qualitative studies of IGMVs, we found that these groups acted as workarounds implemented by clinicians seeking to innovate upon standard pain management protocols. While clinical uncertainty is often framed as a problem to be managed, in this instance, overlapping uncertainties provided an opportunity through which enterprising clinicians could generate reform at the local level. However, these clinician-led changes were incremental, situational, and partial, and occurred outside of broader systemic reform. In the following article, we draw on 46 interviews with clinicians and staff associated with IGMVs and observations of 34 sessions of 22 distinct IGMVs. We begin by describing the structure of the IGMVs we observed. We analyze the multiple uncertainties surrounding chronic pain and its treatment at the time of our data collection, just before the opioid crisis was declared a national public health emergency. We then demonstrate how clinicians tinkered with existing pain management protocols via their involvement with IGMVs. Lastly, we discuss the conditions of possibility that allowed for the existence of IGMVs at our study sites, as well as the conditions of limitation that restricted the expansion of these groups. Our research points to the potential of IGMVs for treating chronic pain, while showing that IGMVs continue as an innovation by individual clinicians, not as a result of broader reforms.

Effective communication in the era of precision medicine: A pilot intervention with low health literacy patients to improve genetic counseling communication.

Effective communication, where all parties share a common understanding, is necessary to realize the promise of Genomic Medicine. It is especially salient given the imperative to increase the participation of diverse populations in genomics research and to expand the reach of clinical genomics. We have previously shown that cancer genetic counseling is suboptimal for patients with limited health literacy. To address this finding, we implemented a pilot study to improve verbal communication between genetic counselors and their patients of limited health literacy that consisted of: i) curriculum development and delivery of a Genetic Counselors (GC) communication workshop; ii) two-month post-workshop interviews with GC participants (n = 9); iii) observations/audio recordings of counseling sessions involving 24 patients and two GC workshop participants; iv) post-counseling interviews with patients (n = 9). The 4.5-h workshop presented evidenced-based principles and strategies for effective communication with limited health literacy patients (e.g. use of plain language and teach-back), and offered specific techniques and exercises to practice adoption of such practices in the genetic counseling context. GCs expressed appreciation for the opportunity to refine their skills; however, they reported that some strategies were challenging given their professional training and communication habits. For example, GCs were concerned that use of plain language could undermine efforts to obtain informed consent and provide scientifically accurate information. Observations and patient interviews after the workshop revealed that GCs were able to employ the communication strategies with positive effects, with patients indicating sufficient understanding of the genetic test and its implications as well as satisfaction with the counselors' communication. While derived from research on communication with those of limited health literacy, the communication approaches taught in the GC workshop could benefit most patients, given the high rates of low health literacy in many countries, and the many factors beyond health literacy that can contribute to reduced comprehension in health care environments.

Like a Fish out of Water: Managing Chronic Pain in the Urban Safety Net.

The subjective nature of pain has always rendered it a point of entry for power and corresponding stratifying processes within biomedicine. The opioid crisis has further exacerbated these challenges by increasing the stakes of prescribing decisions for providers, which in turn has resulted in greater treatment disparities. Using the theoretical frame of cultural health capital (CHC) to account for these disparities in pain management as they unfold at both the macro- and the microlevel, we present findings from an interdisciplinary study of two complex care management programs in urban safety-net hospitals that serve high-utilizing patients. CHC, which considers the ways in which patient-provider interactions reflect and often reinforce broader social inequities, allows for a consideration of power as it circulates through and beyond the patient-provider encounter. Within the current sociopolitical era of pain management, attention must be paid to the stratifying processes that structure how suffering is addressed.

Defining trauma in complex care management: Safety-net providers' perspectives on structural vulnerability and time.

In this paper, we delineate how staff of two complex care management (CCM) programs in urban safety net hospitals in the United States understand trauma. We seek to (1) describe how staff in CCM programs talk about trauma in their patients' lives; (2) discuss how trauma concepts allow staff to understand patients' symptoms, health-related behaviors, and responses to care as results of structural conditions; and (3) delineate the mismatch between long-term needs of patients with histories of trauma and the short-term interventions that CCM programs provide. Observation and interview data gathered between February 2015 and August 2016 indicate that CCM providers define trauma expansively to include individual experiences of violence such as childhood abuse and neglect or recent assault, traumatization in the course of accessing health care and structural violence. Though CCM staff implement elements of trauma-informed care, the short-term design of CCM programs puts pressure on the staff to titrate their efforts, moving patients towards graduation or discharge. Trauma concepts enable clinicians to name structural violence in clinically legitimate language. As such, trauma-informed care and structural competency approaches can complement each other.

Patient engagement at the margins: Health care providers' assessments of engagement and the structural determinants of health in the safety-net.

Increasing "patient engagement" has become a priority for health care organizations and policy-makers seeking to reduce cost and improve the quality of care. While concepts of patient engagement have proliferated rapidly across health care settings, little is known about how health care providers make use of these concepts in clinical practice. This paper uses 20 months of ethnographic and interview research carried out from 2015 to 2016 to explore how health care providers working at two public, urban, safety-net hospitals in the United States define, discuss, and assess patient engagement. We investigate how health care providers describe engagement for high cost patients-the "super-utilizers" of the health care system-who often face complex challenges related to socioeconomic marginalization including poverty, housing insecurity, exposure to violence and trauma, cognitive and mental health issues, and substance use. The health care providers in our study faced institutional pressure to assess patient engagement and to direct care towards engaged patients. However, providers considered such assessments to be highly challenging and oftentimes inaccurate, particularly because they understood low patient engagement to be the result of difficult socioeconomic conditions. Providers tried to navigate the demand to assess patient engagement in care by looking for explicit positive and negative indicators of engagement, while also being sensitive to more subtle and intuitive signs of engagement for marginalized patients.

Life Expectancy With and Without Pain in the U.S. Elderly Population.

BACKGROUND: This study contributes to dialogue on quality versus quantity of life by examining years older persons can expect to live in various states of pain. METHODS: Data from seven waves of the Health and Retirement Study; N = 26,896; age 55+. Estimations using the Interpolative Markov Chain approach apply probability transitions to multistate life table functions. Two estimates are interpreted: (i) population-based, which provide population averages aggregated across baseline states and (ii) status-based, which provide independent estimates by baseline state. Age- and sex-specific years with no pain, milder nonlimiting, and severe or limiting pain are reported as is percent of life in states of pain. RESULTS: Females have higher life expectancy than males but similar expectations of pain-free life. Total life expectancy varies only slightly by baseline pain states but pain-free life expectancy varies greatly. For example, an 85-year-old female pain-free at baseline expects 7.04 more years, 5.28 being pain-free. An 85-year-old female with severe pain at baseline expects 6.42 years with only 2.66 pain-free. Percent of life with pain decreases by age for those pain-free at baseline and increases for those with pain at baseline. CONCLUSION: Pain is moderately associated with quantity of or total life but substantially and importantly associated with quality of or pain-free life.

Pain and self-assessed health: does the association vary by age?

The association between pain and self-assessed health among adults age 20 and older is examined with data from the 2003-2004 National Health and Nutrition Examination Survey, a cross-sectional nationally representative survey of the civilian, non-institutionalized US population. Models emphasize whether and how the association differs across age cohorts. 5032 respondents age 20 and older were asked about their experience with pain. Responses are used to create two different pain measures: general and site-specific. Self-assessed health is categorized into groups that are ordered from fair/poor to excellent. Bivariate analyses and ordered logistic regressions reveal pain, measured both ways, have robust inverse associations with self-assessed health. Associations remain robust after adjusting for a series of health conditions and indicators plus demographic, socioeconomic and social support characteristics. Models test the effect of age by pain interactions on self-assessed health and confirm substantial variation across cohorts. Those of middle-age, 40-59, display the strongest association while self-assessed health is virtually unassociated among older-old, those 80 and older. Findings suggest that the way pain impacts self-assessed health varies by age cohort. Conclusions discuss the importance of considering pain as a health condition and the implications of the findings for well-being across age cohorts.

Leveraging partnerships among community pharmacists, pharmacies, and health departments to improve pandemic influenza response.

Response to public health emergencies requires coordination across multiple sectors and effective use of existing resources in communities. With the expanded role of community pharmacists in public health during the past decade, their participation in response to emergencies has become increasingly important. Local health departments play a lead role in local public health emergency responses, and their ability to develop and leverage partnerships has become increasingly vital given their funding and personnel shortages. This article offers insight and recommendations on how local health departments can most effectively develop and maintain relationships with community pharmacies and pharmacists that will allow for a more coordinated and resourceful public health response to emergencies, and specifically to pandemic influenza outbreaks. Additionally, state and local health departments should reach out to pharmacies in a synchronized way to incorporate them into their pandemic influenza planning and response efforts. As pharmacists continue to expand their role as part of the public health system, pharmacy staff can be active participants with public health agencies to improve community public health emergency response.