Advancing maturity modeling for precision oncology

Introduction

This study aimed to map the maturity of precision oncology as an example of a Learning Health System by understanding the current state of practice, tools and informatics, and barriers and facilitators of maturity.

Methods

We conducted semi-structured interviews with 34 professionals (e.g., clinicians, pathologists, and program managers) involved in Molecular Tumor Boards (MTBs). Interviewees were recruited through outreach at 3 large academic medical centers (AMCs) (n = 16) and a Next Generation Sequencing (NGS) company (n = 18). Interviewees were asked about their roles and relationships with MTBs, processes and tools used, and institutional practices. The interviews were then coded and analyzed to understand the variation in maturity across the evolving field of precision oncology.

Results

The findings provide insight into the present level of maturity in the precision oncology field, including the state of tooling and informatics within the same domain, the effects of the critical environment on overall maturity, and prospective approaches to enhance maturity of the field. We found that maturity is relatively low, but continuing to evolve, across these dimensions due to the resource-intensive and complex sociotechnical infrastructure required to advance maturity of the field and to fully close learning loops.

Conclusion

Our findings advance the field by defining and contextualizing the current state of maturity and potential future strategies for advancing precision oncology, providing a framework to examine how learning health systems mature, and furthering the development of maturity models with new evidence.

Reported Interest in Notification Regarding Use of Health Information and Biospecimens

This study describes reported interest in notification regarding use of personal health information and biospecimens for research and preference-associated factors among a sample of the US population in 2019.

Learning about COVID-19: sources of information, public trust, and contact tracing during the pandemic

Objective

To assess the association between public attitudes, beliefs, and information seeking about the COVID-19 pandemic and willingness to participate in contact tracing in Michigan.

Methods

Using data from the quarterly Michigan State of the State survey conducted in May 2020 (n = 1000), we conducted multiple regression analyses to identify factors associated with willingness to participate in COVID-19 contact tracing efforts.

Results

Perceived threat of the pandemic to personal health (B = 0.59, p = <.00, Ref = No threat) and general trust in the health system (B = 0.17, p < 0.001), were the strongest positive predictors of willingness to participate in contact tracing. Concern about misinformation was also positively associated with willingness to participate in contact tracing (B = 0.30, p < 0.001; Ref = No concern). Trust in information from public health institutions was positively associated with willingness to participate in contact tracing, although these institutions were not necessarily the main sources of information about COVID-19.

Conclusion

Policy makers can enhance willingness to participate in public health efforts such as contact tracing during infectious disease outbreaks by helping the public appreciate the seriousness of the public health threat and communicating trustworthy information through accessible channels.

A survey of computable biomedical knowledge repositories

Introduction

While data repositories are well-established in clinical and research enterprises, knowledge repositories with shareable computable biomedical knowledge (CBK) are relatively new entities to the digital health ecosystem. Trustworthy knowledge repositories are necessary for learning health systems, but the policies, standards, and practices to promote trustworthy CBK artifacts and methods to share, and safely and effectively use them are not well studied.

Methods

We conducted an online survey of 24 organizations in the United States known to be involved in the development or deployment of CBK. The aim of the survey was to assess the current policies and practices governing these repositories and to identify best practices. Descriptive statistics methods were applied to data from 13 responding organizations, to identify common practices and policies instantiating the TRUST principles of Transparency, Responsibility, User Focus, Sustainability, and Technology.

Results

All 13 respondents indicated to different degrees adherence to policies that convey TRUST. Transparency is conveyed by having policies pertaining to provenance, credentialed contributors, and provision of metadata. Repositories provide knowledge in machine-readable formats, include implementation guidelines, and adhere to standards to convey Responsibility. Repositories report having Technology functions that enable end-users to verify, search, and filter for knowledge products. Less common TRUST practices are User Focused procedures that enable consumers to know about user licensing requirements or query the use of knowledge artifacts. Related to Sustainability, less than a majority post describe their sustainability plans. Few organizations publicly describe whether patients play any role in their decision-making.

Conclusion

It is essential that knowledge repositories identify and apply a baseline set of criteria to lay a robust foundation for their trustworthiness leading to optimum uptake, and safe, reliable, and effective use to promote sharing of CBK. Identifying current practices suggests a set of desiderata for the CBK ecosystem in its continued evolution.

"If It Needs to be Done, It Needs to be Done": National Survey of Youth Experiences and Perspectives on Caregiving

PURPOSE

The purpose of this study was to explore youth experiences and perspectives on family caregiving to improve programs and policies that impact the well-being of youth.

METHODS

In August 2020, we asked three open-ended questions about current and anticipated caregiving responsibilities, impact, and needs using MyVoice, a national text message poll of youth. Content and thematic analysis was conducted to evaluate qualitative responses.

RESULTS

In our sample (n = 1,076), 35% of respondents reported previously or currently providing care for an adult relative either independently or by helping another relative. Participants believed caregiving had or would hinder their educational or career goals and that specific training would better prepare them to be a caregiver.

CONCLUSIONS

The prevalence of youth caregiving may be higher than previous estimates. Healthcare professionals should evaluate youth for caregiving responsibilities and support them in identifying resources or interventions to reduce potential impacts of caregiving burden on health outcomes.

What Does "Patient-Centered" Mean? Qualitative Perspectives from Older Adults and Family Caregivers

This study aimed to (1) examine what patient-centeredness means for older adults and family caregivers, and (2) assess circumstances underlying their preference for geriatric care. We conducted separate focus groups with older adults and family caregivers of older adults about health care experiences and expectations and conducted a vignette-based experiment to assess preference for geriatric care. Participants expressed a need for greater skill and empathy and integration of caregivers. They preferred geriatric care to usual primary care with increasing social, health, and healthcare complexity. Distinct needs of older adults should be considered in referral practices to geriatric medicine.

Exploring How Personal, Social, and Institutional Characteristics Contribute to Geriatric Medicine Subspecialty Decisions: A Qualitative Study of Trainees' Perceptions

PURPOSE

To explore internal medicine residents' and geriatrics fellows' perceptions of how personal, social, and institutional characteristics contribute to their professional identity and subspecialty decisions related to geriatric medicine.

METHOD

The authors conducted 23 in-depth, semistructured interviews with internal medicine residents, with and without an interest in geriatrics, and geriatrics fellows across 3 academic medical centers in the United States from October 2018 through June 2019. They then used a qualitative narrative approach to analyze the interview data.

RESULTS

Trainees related personal experiences, such as exposure to physicians and experiences with grandparents, to their interest in medicine. Trainees with an interest in geriatrics at 2 institutions did not feel supported, or understood, by peers and mentors in their respective institutions but maintained their interest in the field. The following variations between institutions that are supportive and those that are not were noted: the number of geriatricians, the proximity of the institution to geriatrics clinics, and the ways in which institutional leaders portrayed the prestige of geriatric medicine. Institutional characteristics influenced trainees' understanding of what it meant to be a doctor, what meaning they garnered from work as a physician, and their comfort with different types of complexity, such as those presented when providing care to older adults.

CONCLUSIONS

Institutional characteristics may be particularly important in shaping trainee interest in geriatric medicine. Institutions should encourage leadership training and opportunities for geriatricians so they can serve as role models and as hands-on mentors for trainees beginning in medical school. Increasing the number of geriatricians requires institutions to increase the value they place on geriatrics to generate a positive interest in this field among trainees. Institutions facilitating formation of professional identity and sense of purpose in work may consider engaging geriatricians in leadership and mentoring roles as well as curriculum development.

Do people have an ethical obligation to share their health information? Comparing narratives of altruism and health information sharing in a nationally representative sample

BACKGROUND

With the emergence of new health information technologies, health information can be shared across networks, with or without patients' awareness and/or their consent. It is often argued that there can be an ethical obligation to participate in biomedical research, motivated by altruism, particularly when risks are low. In this study, we explore whether altruism contributes to the belief that there is an ethical obligation to share information about one's health as well as how other health care experiences, perceptions, and concerns might be related to belief in such an obligation.

METHODS

We conducted an online survey using the National Opinion Research Center's (NORC) probability-based, nationally representative sample of U.S. adults. Our final analytic sample included complete responses from 2069 participants. We used multivariable logistic regression to examine how altruism, together with other knowledge, attitudes, and experiences contribute to the belief in an ethical obligation to allow health information to be used for research.

RESULTS

We find in multivariable regression that general altruism is associated with a higher likelihood of belief in an ethical obligation to allow one's health information to be used for research (OR = 1.22, SE = 0.14, p = 0.078). Trust in the health system and in care providers are both associated with a significantly higher likelihood of believing there is an ethical obligation to allow health information to be used (OR = 1.48, SE = 0.76, p<0.001; OR = 1.58, SE = 0.26, p<0.01, respectively).

CONCLUSIONS

Belief that there is an ethical obligation to allow one's health information to be used for research is shaped by altruism and by one's experience with, and perceptions of, health care and by general concerns about the use of personal information. Altruism cannot be assumed and researchers must recognize the ways encounters with the health care system influence (un)willingness to share one's health information.

Patient-Reported Experiences of Discrimination in the US Health Care System

IMPORTANCE

Although considerable evidence exists on the association between negative health outcomes and daily experiences of discrimination, less is known about such experiences in the health care system at the national level. It is critically necessary to measure and address discrimination in the health care system to mitigate harm to patients and as part of the larger ongoing project of responding to health inequities.

OBJECTIVES

To (1) identify the national prevalence of patient-reported experiences of discrimination in the health care system, the frequency with which they occur, and the main types of discrimination experienced and (2) examine differences in the prevalence of discrimination across demographic groups.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional national survey fielded online in May 2019 used a general population sample from the National Opinion Research Center's AmeriSpeak Panel. Surveys were sent to 3253 US adults aged 21 years or older, including oversamples of African American respondents, Hispanic respondents, and respondents with annual household incomes below 200% of the federal poverty level.

MAIN OUTCOMES AND MEASURES

Analyses drew on 3 survey items measuring patient-reported experiences of discrimination, the primary types of discrimination experienced, the frequency with which they occurred, and the demographic and health-related characteristics of the respondents. Weighted bivariable and multivariable logistic regressions were conducted to assess associations between experiences of discrimination and several demographic and health-related characteristics.

RESULTS

Of 2137 US adult respondents who completed the survey (66.3% response rate; unweighted 51.0% female; mean [SD] age, 49.6 [16.3] years), 458 (21.4%) reported that they had experienced discrimination in the health care system. After applying weights to generate population-level estimates, most of those who had experienced discrimination (330 [72.0%]) reported experiencing it more than once. Of 458 reporting experiences of discrimination, racial/ethnic discrimination was the most common type (79 [17.3%]), followed by discrimination based on educational or income level (59 [12.9%]), weight (53 [11.6%]), sex (52 [11.4%]), and age (44 [9.6%]). In multivariable analysis, the odds of experiencing discrimination were higher for respondents who identified as female (odds ratio [OR], 1.88; 95% CI, 1.50-2.36) and lower for older respondents (OR, 0.98; 95% CI, 0.98-0.99), respondents earning at least $50 000 in annual household income (OR, 0.76; 95% CI, 0.60-0.95), and those reporting good (OR, 0.59; 95% CI, 0.46-0.75) or excellent (OR, 0.41; 95% CI, 0.31-0.56) health compared with poor or fair health.

CONCLUSIONS AND RELEVANCE

The results of this study suggest that experiences of discrimination in the health care system appear more common than previously recognized and deserve considerable attention. These findings contribute to understanding of the scale at which interpersonal discrimination occurs in the US health care system and provide crucial evidence for next steps in assessing the risks and consequences of such discrimination. The findings also point to a need for further analysis of how interpersonal discrimination interacts with structural inequities and social determinants of health to build effective responses.

Rethinking ethical oversight in the era of the learning health system

Opportunities to advance science increasingly arise through investigations embedded within routine clinical practice in the form of learning health systems. Such activities challenge conventional approaches to research regulation that have not caught up with those opportunities, often imposing burdens generalized from riskier research. We analyze the rules and conventions in the US, demonstrating how even those rules are compatible with a much more flexible approach to participant risk, institutional oversight, participant consent, and disclosure for low-risk learning activities in all jurisdictions.

Building and maintaining trust in clinical decision support: Recommendations from the Patient-Centered CDS Learning Network

Knowledge artifacts in digital repositories for clinical decision support (CDS) can promote the use of CDS in clinical practice. However, stakeholders will benefit from knowing which they can trust before adopting artifacts from knowledge repositories. We discuss our investigation into trust for knowledge artifacts and repositories by the Patient-Centered CDS Learning Network's Trust Framework Working Group (TFWG). The TFWG identified 12 actors (eg, vendors, clinicians, and policy makers) within a CDS ecosystem who each may play a meaningful role in prioritizing, authoring, implementing, or evaluating CDS and developed 33 recommendations distributed across nine "trust attributes." The trust attributes and recommendations represent a range of considerations such as the "Competency" of knowledge artifact engineers and the "Organizational Capacity" of institutions that develop and implement CDS. The TFWG findings highlight an initial effort to make trust explicit and embedded within CDS knowledge artifacts and repositories and thus more broadly accepted and used.

An Analysis of the Learning Health System in Its First Decade in Practice: Scoping Review

Background

In the past decade, Lynn Etheredge presented a vision for the Learning Health System (LHS) as an opportunity for increasing the value of health care via rapid learning from data and immediate translation to practice and policy. An LHS is defined in the literature as a system that seeks to continuously generate and apply evidence, innovation, quality, and value in health care.

Objective

This review aimed to examine themes in the literature and rhetoric on the LHS in the past decade to understand efforts to realize the LHS in practice and to identify gaps and opportunities to continue to take the LHS forward.

Methods

We conducted a thematic analysis in 2018 to analyze progress and opportunities over time as compared with the initial Knowledge Gaps and Uncertainties proposed in 2007.

Results

We found that the literature on the LHS has increased over the past decade, with most articles focused on theory and implementation; articles have been increasingly concerned with policy.

Conclusions

There is a need for attention to understanding the ethical and social implications of the LHS and for exploring opportunities to ensure that these implications are salient in implementation, practice, and policy efforts.

Trust in provider care teams and health information technology-mediated communication

Teams of healthcare providers use health information technology (HIT) to facilitate communication and collaboration. Effective team-based care requires trust, yet we know relatively little about how physicians build and maintain trust with their fellow providers and, further, how HIT affects trust among provider team members. We describe priority areas for advancing our understanding of trust within healthcare teams, which may inform policies and HIT design in efforts to improve clinical decision making, provider satisfaction, quality of care, and patient health outcomes.

Dynamics of Physicians' Trust in Fellow Health Care Providers and the Role of Health Information Technology

Physicians are expected and incentivized to coordinate patient care with other providers, including nonphysician clinician (NPC) members of care teams, requiring trust. Trust in the context of care teams has not been well-studied; even less is known about how health information technologies (HIT) may modify trust in these relationships. We conducted semistructured interviews with 30 physicians at a Midwestern academic center to examine how physicians determine they can trust NPCs, and how technology modifies these relationships. A majority of physicians base trust in NPCs on cognitive factors such as competence and reliability. Technology enhances trust between physicians and NPCs by supporting evidence-based decision making; it can also erode trust by limiting opportunities for developing familiarity and comfort with fellow providers. Our work has implications for enhancing HIT to promote trust between providers, and for developing more robust measures of trust that can be used in evaluating and improving teamwork within practices.

Public Trust in Health Information Sharing: A Measure of System Trust

OBJECTIVE

To measure public trust in a health information sharing in a broadly defined health system (system trust), inclusive of health care, public health, and research; to identify individual characteristics that predict system trust; and to consider these findings in the context of national health initiatives (e.g., learning health systems and precision medicine) that will expand the scope of data sharing.

DATA SOURCES

Survey data (n = 1,011) were collected in February 2014.

STUDY DESIGN

We constructed a composite index of four dimensions of system trust-competency, fidelity, integrity, and trustworthiness. The index was used in linear regression evaluating demographic and psychosocial predictors of system trust.

DATA COLLECTION

Data were collected by GfK Custom using a nationally representative sample and analyzed in Stata 13.0.

PRINCIPAL FINDINGS

Our findings suggest the public's trust may not meet the needs of health systems as they enter an era of expanded data sharing. We found that a majority of the U.S. public does not trust the organizations that have health information and share it (i.e., the health system) in one or more dimensions. Together, demographic and psychosocial factors accounted for ~18 percent of the observed variability in system trust. Future research should consider additional predictors of system trust such as knowledge, attitudes, and beliefs to inform policies and practices for health data sharing.

'Born in Michigan? You're in the biobank': engaging population biobank participants through Facebook advertisements

BACKGROUND/AIMS

Despite a broad call for biobanks to use social media, data is lacking regarding the capacity of social media tools, especially advertising, to engage large populations on this topic.

METHODS

We used Facebook advertising to engage Michigan residents about the BioTrust for Health. We conducted a low-budget (<USD 5,000), 26-day social media campaign targeting Michigan residents aged 18-28. We placed 25 Facebook advertisements and analyzed their performance in terms of reach and cost across 3 engagement types: passive, active and interactive. We compared engagement before, during and after the campaign.

RESULTS

The Facebook page was viewed 1,249 times during the month of the advertising campaign, versus once in the month prior. 779,004 Michigan residents saw ads an average of 25.8 times; 4,275 clicked ads; the average click-through-ratio was 0.021%. Interactions included 516 'likes' and 30 photo contest entries. Cost per outcome ranged from <USD 0.005 per exposure to USD 182 per photo entry. The average cost per click was USD 1.04.

CONCLUSION

A social media strategy to build public awareness about biobanking is not likely to be effective without a promotional 'push' to distribute content. Social media advertisements have the capacity to scale-up engagement on biobanking while keeping costs manageable. Facebook advertisements provide necessary access points for unaware participants, with implications for public trust.

C-fos expression in vivo in human lymphocytes in response to stress

1. Blood samples from which lymphocytes were isolated were obtained from patients immediately prior to cardiac catheterization (stress period) and again four to five hours later (post-stress period). Blood was also taken from a normal non-stressed control subject. 2. Lymphocyte c-fos mRNA was reverse transcribed followed by strand synthesis of DNA template and amplification using PCR with sequence-specific primers. 3. C-fos mRNA was detectable in lymphocytes from the normal control subject and in patient samples obtained immediately prior to cardiac catheterization, but was not detectable in patient samples obtained four to five hours later. 4. Possible mechanisms for these findings include a stress-related decrease in lymphocyte proliferation and differentiation or a negative feedback effect of the c-fos protein on transcription of the c-fos gene. 5. These findings suggest that it may be possible to monitor peripheral early gene expression as a marker for a variety of conditions including stress, psychiatric disorders and the response to psychotropic drugs.

The use of ubiquitin as a marker of thyroxine-induced apoptosis in cultured Rana catesbeiana tail tips

Cultured Rana catesbeiana tadpole tail tips were used in combination with a fluoroimmunoassay to determine the levels of ubiquitin--a protein marker of programmed cell death in other systems--during the tissue regression induced by thyroxine (T4). After a 3-day pretreatment with the hormone, tail tips cultured in T4 showed significant increases in ubiquitin levels by 48 hr. Tail tips taken from tadpoles that had been immersed in T4 for 6 days showed a parallel increase in ubiquitin levels, demonstrating the same change in vivo. Treatment of cultured tail tips with the protein kinase C inhibitor, H-7, blocks both regression and the rise in ubiquitin seen in tips treated with T4 alone. Treatment of cultured tips with T4 and either cycloheximide or actinomycin D inhibits regression compared to T4 alone; however, the rise in ubiquitin is only blocked by cycloheximide, suggesting that ubiquitin is being made from RNA that was synthesized during the pretreatment period or earlier. These results suggest that ubiquitin will serve as a good molecular marker of tissue regression in the T4-treated tadpole tail and that it will be productive to consider tissue regression during amphibian metamorphosis as a specific case of programmed cell death or apoptosis.

Inhibition of protein kinase C antagonizes in vitro tadpole tail fin regression induced by thyroxine

Tail fin regression can be induced in anuran amphibians with L-thyroxine (T4). This regression can be antagonized with prolactin (PRL). Previous work had suggested that protein kinase C (PKC) was involved in PRL action. To address this issue further, the effect of a potent and selective inhibitor of protein kinase C on in vitro tail fin regression was investigated. T4-induced regression of tail fin pieces from Rana pipiens tadpoles could be antagonized by adding PRL or the PKC inhibitor H-7 to the medium. H-7 inhibited fin regression in a dose-dependent manner, with a half-maximal effective concentration of about 10(-5) M. The H-7 analogue, HA-1004 (which is not a selective inhibitor of PKC), was without effect. These results suggest a possible role for PKC in tail fin regression and may be useful in elucidating the antimetamorphic action of PRL.

Reduced calcium and inhibition of protein kinase C mimic the enhancement of ornithine decarboxylase activity of prolactin in Ambystoma tigrinum tissues

We previously reported that prolactin (PRL) could increase the activity of ornithine decarboxylase (ODC) in liver slices taken from larval tiger salamanders (Ambystoma tigrinum). This action of the hormone was inhibited by oxytocin (OT), the calcium ionophore A23187, and diacyglycerol (DG) and was duplicated by 10 microM verapamil (VML), a calcium channel blocker. Here, we expand these results to show that 1) a higher dose of VML (50 microM) produces an additive effect with PRL; 2) addition of small amounts of calcium (0.1 mM) to the liver culture medium blocks PRL action; 3) neither nifedipine (NIF), a different type of calcium channel blocker, nor EDTA alter PRL action; and 4) gossypol, a reported inhibitor of protein kinase C, mimics PRL action. Additionally, we show that PRL increases ODC activity in tiger salamander tail skin in vitro, a tissue previously demonstrated to be a PRL target tissue in this species. The same set of treatments which we have shown to modify PRL effects on ODC in liver slices affects PRL action in the tail skin in a parallel manner. Thus, the mechanism whereby PRL enhances ODC activity appears to be the same in both these tissues. These results are discussed in conjunction with the findings from similar studies using mammalian tissues in an attempt to assess the current picture of the mechanism of PRL action and the possible role of inositol phospholipid turnover, calcium, and protein kinase C in the action of this hormone.

Enhancement of ornithine decarboxylase activity in Ambystoma liver slices by ovine prolactin: an evaluation of possible mediators

Prolactin has been shown to increase the activity of ornithine decarboxylase in a variety of mammalian tissues and in the pigeon crop sac. This study demonstrates a similar effect of ovine prolactin on ornithine decarboxylase activity in liver slices taken from larval tiger salamanders (Ambystoma tigrinum). An evaluation of potential mediators of prolactin action in liver slices revealed that the effect of the hormone on enzyme activity was not blocked by ouabain, an inhibitor of the sodium pump reported to block other actions of prolactin. Oxytocin, which inhibits prolactin actions in A. tigrinum, blocked the increase in ornithine decarboxylase activity induced by prolactin. Since previous results had implicated inositol phospholipid turnover in oxytocin action, the effects of the calcium ionophore, A 23187, and of synthetic diacylglycerol were examined. Both agents blocked the increase in enzyme activity when they were combined with prolactin treatment. Verapamil, a calcium channel blocker, had a prolactin-like effect on the activity of ornithine decarboxylase, and the combination of prolactin and verapamil produced a stimulation of the enzyme that was no greater than that observed with either the drug or prolactin alone, suggesting that both agents might be acting via a common cellular pathway. The tentative hypothesis that prolactin acts via a mechanism which lowers intracellular calcium is suggested.

Effects of prenatal exposure to neuroleptic drugs on children's growth

The effect of prenatal exposure to neuroleptic drugs on height and weight from birth to 7 years was examined in children of psychiatrically normal parents and of parents with a history of psychiatric treatment, using data from the Collaborative Perinatal Project of the National Institute of Neurological Diseases, Communicative Disorders, and Stroke. Analysis of covariance was used to control for potential confounding factors. We found that prenatal exposure to dopamine receptor-blocking neuroleptic drugs was associated with increased height in one or more of our groups at 4 months, 1 year, and 7 years and less consistently with increased weight. Seven-year-old children who had been exposed to these drugs for more than 2 months during gestation were approximately 3 cm taller than unexposed controls (p less than 0.05). Prenatal exposure to dopamine-depleting agents was associated with decreased height at 4 months but not later. Possible mechanisms for these effects, including a permanent decrease in the number of brain dopamine receptors and effects on various hormones, are discussed.

Effect of repeated restraint stress, desmethylimipramine or adrenocorticotropin on the alpha and beta adrenergic components of the cyclic AMP response to norepinephrine in rat brain slices

The cyclic AMP response to catecholamines in rat cortical slices is mediated by a beta adrenergic receptor which is coupled to adenylate cyclase and an alpha adrenergic receptor which potentiates the response to beta receptor stimulation. The present studies examined the effects of repeated restraint stress, adrenocorticotropin or desmethylimipramine administration on the beta and alpha adrenergic components of this response. Restraint was found to produce a small nonsignificant decrease of the beta receptor response accompanied by a significant reduction of the alpha receptor-induced potentiation of the beta response. Desmethylimipramine was found to lower the cyclic AMP response to beta receptor stimulation but not to alter the alpha-induced potentiation of the beta response. Adrenocorticotropin, like restraint stress, was found to reduce only the alpha-induced potentiation of the beta response. Experiments with adenosine and histamine showed that restraint stress lowered the alpha-induced potentiation of cyclic AMP responses to these neurohormones also. It is concluded that restraint stress acts primarily to reduce the response to stimulation of central alpha adrenergic receptors whereas desmethylimipramine acts primarily to reduce the response to stimulation of beta adrenergic receptors. Adrenocorticotropin has the same effect as restraint stress suggesting that pituitary adrenal hormones mediate the stress effect.

Antagonistic effects of prolactin and oxytocin on tail fin regression and acid phosphatase activity in metamorphosing Ambystoma tigrinum

We have found that the inhibition of thyroxine-induced tail fin regression by prolactin in larval tiger salamanders is antagonized by oxytocin. Other workers have shown that prolactin blocks the rise in activity of several hydrolytic enzymes that occurs in regressing tissue during metamorphosis. Here, we examine the effects of prolactin and oxytocin--given alone and in combination--on tail fin regression and acid phosphatase specific activity in this tissue. Both long-term (12-day) and short-term (48-hr) treatment paradigms using prolactin and oxytocin are investigated. The results show that long-term prolactin treatment of metamorphosing larvae blocks fin regression and the rise in acid phosphatase specific activity seen in metamorphosing controls; short-term prolactin treatment of metamorphosing larvae inhibits fin regression within 48 hr, but does not block the rise in acid phosphatase activity seen in controls; oxytocin antagonizes the effects of prolactin on tail fin regression; and oxytocin treatment (long-term or short-term) of metamorphosing larvae causes an elevation of acid phosphatase activity above that seen in metamorphosing controls. With long-term treatment, this effect of oxytocin is slightly antagonized by prolactin; with short-term treatment, no antagonism is observed even though an effect of prolactin on fin height is still evident. We have interpreted these results as suggesting that the effect of prolactin on hydrolase activity is not a prerequisite for its inhibitory effect on fin regression to occur.

Reduction of the cyclic adenosine 3',5'-monophosphate response to catecholamines in rat brain slices after repeated restraint stress

Restraint stress reduces the cyclic AMP (cAMP) response to norepinephrine (NE) in slices of the rat cerebral cortex and hypothalamus. This effect is found after repeated but not single exposure to stress and persists for at least 24 hr poststress. The magnitude of the reduction is dose-dependent in that greater decreases are found after higher frequencies and longer durations of restraint as well as after more disturbance during the stress. Analysis of the NE-cAMP dose-response curve indicates that the stress reduces the maximum cAMP response to NE but does not increase the EC50 value of NE. The cAMP response to isoproterenol is only slightly affected by the stress. No effect is observed on specific [3H]dihydroalprenolol binding in either brain region at 24 hr poststress. These results suggest that repeated restraint stress produces a selective persistent reduction of the function of brain non-beta adrenergic receptors. This effect may be mediated by an increased release of adrenocorticotropic hormone as chronic infusion of the latter hormone mimics the action of stress on cAMP responses to catecholamines. An increased release of brain NE may also be involved as repeated administration of the NE-reuptake inhibiting antidepressant, desmethylimipamine, reduces the function of non-beta as well as beta adrenergic receptors as evidenced by reductions of both the NE- and isoproterenol-cAMP responses.

Cognitive effects of lithium carbonate and haloperidol in treatment-resistant aggressive children

The effects of lithium carbonate and haloperidol on cognition were examined in a placebo-controlled, double-blind study of 61 treatment-resistant, hospitalized school-aged children. They all had a DSM-III diagnosis of conduct disorder-- undersocialized , aggressive, with a profile of highly explosive and aggressive behavior. Children were assessed at the end of a two-week placebo-baseline period and again after four weeks of treatment. Drug effects on cognition were mild. Haloperidol (mean dose, 2.95 mg/day) caused significant decreases in Porteus Maze test quotient scores and a slowing of reaction time (RT) on a simple RT task. Lithium carbonate (mean dose, 1,166 mg/day) adversely affected qualitative scores on the Porteus Maze test. No significant treatment effects were found for the Matching Familiar Figures Test, short-term recognition memory and concept attainment tasks, or the Stroop Test.

Reduction of the cAMP response to norepinephrine in rat cerebral cortex following repeated restraint stress

The present studies examined the effect of restraint stress on the sensitivity of the catecholamine-cAMP generating system in the rat cerebral cortex. Restraint was found to cause a persistent reduction in the magnitude of the cAMP response to catecholamines. This effect occurred after repeated but not acute stress and was more marked with twice-daily as compared to once-daily treatment. The reduction in response was more marked with norepinephrine than with isoproterenol, indicating a selective action of stress on the non-beta component of the noradrenergic response. The findings suggest that subsensitivity of the cAMP response to norepinephrine is a general response to chronic stressful stimuli and may be related to the action of certain antidepressant agents.

The effect of acute and chronic administration of desmethylimipramine on responses to stress in rats

Rats were given single or repeated injection of desmethylimipramine (DMI) and subjected to a single session of restraint or footshock stress. The degree of anorexia and plasma corticosterone elevation in response to the stress was measured. Repeated but not single injection of DMI was found to reduce the anorectic response to restraint and footshock but not to affect the corticosterone response to restraint. It is concluded that repeated DMI treatment has differential effects on responses to acute stress.

Chronic restraint stress elicits a positive antidepressant response on the forced swim test

The present study investigated behavioral parallels between adaptation to stress and antidepressant treatment using the forced swim test. Restraint stress given repeatedly for 11 days significantly reduced immobility on this test. A single application of stress had no effect. The reduction in immobility produced by repeated restraint was quantitatively similar to that produced by repeated administration of desmethylimipramine. These results confirm previous findings of similarities in the behavioral and neurochemical response to chronic stress and chronic antidepressant treatment.

Brain adrenergic receptors and resistance to stress

The relationship between brain beta-adrenergic receptors and adaptation to stress was studied in rats subjected to repeated restraint stress. The stress was found to produce a reduction in the density of these receptors in the hypothalamus, cerebral cortex and brain stem. This change first appeared after 4-7 days and persisted for the duration of the two-week stress. Adaptation, as judged by resistance to the anorexic and gastric lesion-inducing effects of the stress, occurred progressively over the full two-week period. The loss of beta-receptors was found to correlate positively with the degree of adaptation. The relationship was strongest for the hypothalamus but was also apparent in the cortex and brain stem. These findings support the hypothesis that a reduction in the number of brain adrenergic receptors is one of the biochemical factors underlying adaptation to stress.

Effects of lithium carbonate and haloperidol on cognition in aggressive hospitalized school-age children

A comparison of the effects of lithium, haloperidol, and placebo on cognition is reported for a sample of hospitalized school-age children with a behavioral profile of aggressiveness and explosiveness. In this double-blind study, patients were randomly assigned to one of three treatment conditions. The cognitive battery was administered at the end of a 2-week placebo baseline period and again after 4 weeks of treatment. It included a simple reaction time (RT) task with preparatory intervals of 1, 4, and 8 seconds, the Porteus Mazes, and the Matching Familiar Figures Test. Drug effects on cognition, when found, were mild. Slower and more variable RTs were found on the RT task in the haloperidol group (mean dose, 3.1 mg/day), particularly at the 4- and 8-second preparatory intervals in comparison to placebo. This appeared to reflect decreased ability to hold a preparatory set. No other effects of haloperidol on cognitive performance were found. Lithium carbonate (mean dose, 1150 mg/day) caused a deterioration in qualitative performance on the Porteus Maze Test when compared with haloperidol but had no effect on test quotient scores or on the other cognitive measures. Results are discussed in terms of dose effects and the influences of task demands. This is part of a study critically assessing the effects of lithium and haloperidol on behavioral symptoms and other parameters.

Mast cell histamine and ovarian follicular growth in the lizard Anolis carolinensis

The hypothesis is proposed that histamine released from mast cells in the theca of ovarian follicles increases thecal hyperemia and vessel permeability, and thus plays a role in follicular growth in Anolis carolinensis. Mast cells are present in the stroma and theca, and the number of thecal mast cells increases as follicles grow. The levels of histamine in follicular walls varies with follicular size. Histamine causes vasodilatation of thecal vessels. Antihistamine blocks the effects of histamine and, when given alone, stimulates vasoconstriction. Antihistamine also blocks estradiol-induced growth of large follicles. These findings are consistent with the above hypothesis.