Patterns of Antiseizure Medication Use Following Meningioma Resection: A Single-Institution Experience

OBJECTIVE

To investigate antiseizure medication (ASM) practice behavior for patients who present with seizures before meningioma resection and to review postoperative ASM management.

METHODS

A retrospective study was performed of 112 consecutive patients with meningiomas who underwent resection at a single institution between October 2016 and January 2020. Data were collected through detailed chart review.

RESULTS

Of 112 patients, 35 (31%) had a preoperative seizure, and 43 (38%) were prescribed a preoperative ASM. At discharge, 96 patients (86%) were prescribed an ASM, most often 1000 mg daily of levetiracetam (64%, 61/96) and less often higher doses of levetiracetam or other ASMs. By the 6-month postoperative visit, 55 patients (49%) were taking at least 1 ASM, most commonly levetiracetam monotherapy (65%) at 500 mg twice daily (47%). This number further decreased to 45 (40%) patients by 1-year follow-up and 36 (32%) patients by last-known follow-up. By last follow-up (median 27.3 months; range 5.4-57.4 months), 24 patients (21%) had experienced a postoperative seizure, and 36 patients (32%) were never able to discontinue ASMs. Of patients remaining on levetiracetam monotherapy, only 36% remained on levetiracetam 500 mg twice daily.

CONCLUSIONS

Approximately two thirds (68%) of patients who underwent surgical resection of meningioma were eventually able to completely discontinue their postoperative ASM regimen. However, nearly one third (32%) of patients required long-term ASM management. Levetiracetam monotherapy was the most common ASM prescribed during the postoperative period, and the proportion of patients requiring either higher doses of levetiracetam or alternative ASMs increased over time.

Long-term antiseizure medication use in patients after meningioma resection: identifying predictors for successful weaning and failures

OBJECTIVE

To define risk factors for meningioma-related seizures and predictors of successful weaning of antiseizure medications following meningioma resection.

METHODS

This is a retrospective study of 95 patients who underwent meningioma resection at a single institution. Primary outcome analyzed was ability to achieve seizure freedom without the use of anti-seizure medication at 6-months, 1-year, and last known follow up. Secondary outcome was postoperative seizure freedom.

RESULTS

Preoperative seizures (OR: 11.63, 95% CI [3.64, 37.17], p < 0.0001), non-skull base tumor location (OR: 3.01, 95% CI [1.29, 7.02], p = 0.0128), and modified STAMPE score of 3-5 (OR: 5.42, 95% CI [2.18, 13.52], p = 0.0003) were associated with greater likelihood of remaining on antiseizure medication at 6-month follow up. Preoperative seizures (OR: 4.93, 95% CI: [2.00, 12.16 ], p = 0.0008), intratumoral calcifications (OR: 4.19, 95% CI: [1.61, 14.46], p = 0.0055), modified STAMPE score of 3-5 (OR: 5.42, CI [2.18, 13.52], p = 0.0003), and Ki67 greater than 7% (OR: 5.68, CI [1.61, 20.10], p = 0.0060) were significant risk factors for inability to discontinue ASMs by last follow up. Preoperative seizures (OR: 4.33, 95% CI [1.59, 11.85], p = 0.0050) and modified STAMPE score of 3-5 (OR: 6.09, 95% CI [2.16, 17.20], p = 0.0007) were significant risk factors for postoperative seizures.

CONCLUSIONS

Preoperative seizures, modified STAMPE2 score of 3-5, non-skull base tumor location, intratumoral calcifications, and Ki67 > 7% were significant risk factors for inability to achieve seizure freedom without ASMs. In addition, the modified STAMPE2 score successfully predicted increased seizure risk following meningioma resection for patients with a score of 3 or higher.

Impact of postoperative stereotactic body radiation therapy on survival of patients with spinal metastases in the context of additional systemic adjuvant therapy

BACKGROUND

Stereotactic body radiotherapy (SBRT) has been established as a safe and effective treatment modality for control of long-term pain and tumor growth. However, few studies have investigated the efficacy of postoperative SBRT versus conventional external beam radiation therapy (EBRT) in extending survival within the context of systemic therapy.

METHODS

A retrospective chart review of patients who underwent surgery for spinal metastasis at our institution was conducted. Demographic, treatment and outcome data were collected. SBRT was compared with EBRT and non-SBRT, and analyses were stratified by whether or not patients received systemic therapy. Survival analysis was conducted using propensity score matching.

RESULTS

Bivariate analysis in the non-systemic therapy group revealed longer survival with SBRT compared to EBRT and non-SBRT. Further analysis also showed that primary cancer type and preoperative mRS significantly affected survival. Within patients who received systemic therapy, overall median survival for SBRT patients was 22.7 months (95% CI: 12.1 - 52.3) versus 16.1 months (95% CI: 12.7 - 44.0; p = 0.28) for EBRT patients and 16.1 months (95% CI: 12.2 - 21.9; p = 0.07) for non-SBRT patients. Within patients who did not receive systemic therapy, overall median survival for SBRT patients was 62.1 months (95% CI: 18.1 - unknown) versus 5.3 months (95% CI: 2.8 - unknown; p = 0.08) for EBRT patients and 6.9 months (95% CI: 5.0 - 45.6; p = 0.02) for non-SBRT patients.

CONCLUSION

In patients who do not receive systemic therapy, treatment with postoperative SBRT may increase survival time compared to patients not receiving SBRT.

Meningeal defects and focal cortical dysplasia: an unrecognized relationship? Illustrative case

BACKGROUND

Focal cortical dysplasias (FCDs) are a heterogenous cluster of histopathologic entities classically associated with medically refractory epilepsy. Because there is substantial histopathologic variation among different types of FCD, there are likely multiple pathogenic mechanisms leading to these disorders. The meninges are known to play a role in cortical development, and disruption of meningeal-derived signaling pathways has been shown to impact neurodevelopment. To our knowledge, there has not yet been an investigation into whether genetic pathways regulating meningeal development may be involved in the development of FCD.

OBSERVATIONS

The authors reported a patient with refractory epilepsy and evidence of FCD on imaging who received surgical intervention and was found to have an unusual dural anomaly overlying a region of type Ic FCD. To the authors’ knowledge, this was the first report describing a lesion of this nature in the context of FCD.

LESSONS

The dural anomaly exhibited by the patient presented what could be a potentially novel pathogenic mechanism of FCD. Resection of the cortical tissue underlying the dural anomaly resulted in improvement in seizure control. Although the pathogenesis is unclear, this case highlighted the importance of further investigation into the developmental origins of FCD, which may help elucidate whether a connection between meningeal development and FCD exists.

Characteristics of Scientific Evidence Informing Changed U.S. Preventive Services Task Force Insufficient Evidence Statements

INTRODUCTION

The U.S. Preventive Services Task Force (USPSTF) issues "Insufficient Evidence" (I) statements when scientific evidence is inadequate for making recommendations about clinical preventive services. Insufficient Evidence statements may be changed to definitive recommendations if new research closes evidence gaps. This study examines the characteristics of evidence that informed changes from I statements to definitive recommendations, including NIH's role as a funder.

METHODS

A total of 11 USPSTF Insufficient Evidence statements that were changed between 2010 and 2019 were assessed. Study designs, bibliometric influence, and funding sources for scientific articles cited in USPSTF evidence reviews were characterized for each I statement. Data were analyzed in 2019-2020.

RESULTS

Most I statements (82%) changed to a B grade; an average of 8.4 years elapsed between issuing the I statement and releasing the definitive recommendation. An average of 63 (range=19-253) articles were included in each USPSTF evidence review. NIH support was cited in 28.8% of articles, on average. The proportion of NIH-funded articles reporting RCT designs was similar to that of non-NIH-funded articles (64.5% vs 59.5%). A higher proportion of NIH-funded articles were rated good quality for study design (39.0%) than the proportion of non-NIH-funded articles (24.4%). Bibliometric influence measured by relative citation ratios was higher for NIH-funded (mean=14.78) than for non-NIH-funded (mean=5.07) articles.

CONCLUSIONS

Study designs and funding supports varied widely across topics, but overall, NIH was the largest single funder of evidence informing 11 changed USPSTF I statements. Enhanced efforts by NIH and other stakeholders to address I statement evidence gaps are needed.

Association of e-Cigarette Use With Discontinuation of Cigarette Smoking Among Adult Smokers Who Were Initially Never Planning to Quit

IMPORTANCE

Cigarette smokers not planning to quit are often overlooked in population studies evaluating the risk-benefit potential of electronic nicotine delivery products (e-cigarettes).

OBJECTIVE

To evaluate whether e-cigarette use is associated with discontinuing cigarette smoking among smokers who were initially never planning to quit.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used US nationally representative data from the longitudinal Population Assessment of Tobacco and Health Study (waves 2-5 conducted between October 2014 and November 2019), with participants evaluated in 3 pairs of interviews. Adult daily cigarette smokers initially not using e-cigarettes and with no plans to ever quit smoking for good (2489 observations from 1600 individuals) were included.

EXPOSURES

e-Cigarette use (ie, daily use, nondaily use, or no use) at follow-up interview among smokers not using e-cigarettes at baseline interview.

MAIN OUTCOMES AND MEASURES

The main outcomes were discontinuation of cigarette smoking (ie, no cigarette smoking) and discontinuation of daily cigarette smoking (ie, no daily cigarette smoking) at follow-up interview. Generalized estimating equations were used to evaluate the association between the exposure and each outcome, controlling for demographic characteristics and cigarettes smoked per day at baseline interview; all estimates were weighted.

RESULTS

The weighted population of adult daily cigarette smokers who were not using e-cigarettes and had no plans to ever quit smoking, based on data from 1600 participants, was 56.1% male (95% CI, 53.4%-58.7%), 10.1% Hispanic (95% CI, 8.2%-12.3%), 10.1% non-Hispanic Black (95% CI, 8.7%-11.7%), 75.6% non-Hispanic White (95% CI, 72.9%-78.2%), and 4.2% of other non-Hispanic race (95% CI, 3.3%-5.4%); 29.3% were aged 55 to 69 years (95% CI, 26.2%-32.6%), 8.9% were aged 70 years or older (95% CI, 6.8%-11.5%), 36.8% did not graduate from high school (95% CI, 34.1%-39.6%), 55.2% had an annual household income of less than $25 000 (95% CI, 52.3%-58.1%), 37.6% smoked 20 to 29 cigarettes per day (95% CI, 34.7%-40.6%), and 12.7% smoked 30 or more cigarettes per day (95% CI, 10.9%-14.7%). Overall, 6.2% of the population (95% CI, 5.0%-7.5%) discontinued cigarette smoking. Discontinuation rates were higher among those who used e-cigarettes daily (28.0%; 95% CI, 15.2%-45.9%) compared with not at all (5.8%; 95% CI, 4.7%-7.2%; adjusted odds ratio [aOR], 8.11; 95% CI, 3.14-20.97). Furthermore, 10.7% (95% CI, 9.1%-12.5%) discontinued daily cigarette smoking, with higher rates of discontinuation observed among those who used e-cigarettes daily (45.5%; 95% CI, 27.4%-64.9%) compared with not at all (9.9%; 95% CI, 8.2%-11.8%; aOR, 9.67; 95% CI, 4.02-23.25). Nondaily e-cigarette use was not associated with cigarette discontinuation (aOR, 0.53; 95% CI, 0.08-3.35) or daily cigarette discontinuation (aOR, 0.96; 95% CI, 0.44-2.09).

CONCLUSIONS AND RELEVANCE

In this cohort study, daily e-cigarette use was associated with greater odds of cigarette discontinuation among smokers who initially had no plans to ever quit smoking. These findings support the consideration of smokers who are not planning to quit when evaluating the risk-benefit potential of e-cigarettes for smoking cessation in the population.

New NIH Primary and Secondary Prevention Research During 2012-2019

INTRODUCTION

This manuscript characterizes primary and secondary prevention research in humans and related methods research funded by NIH in 2012‒2019.

METHODS

The NIH Office of Disease Prevention updated its prevention research taxonomy in 2019‒2020 and applied it to a sample of 14,523 new extramural projects awarded in 2012-2019. All projects were coded manually for rationale, exposures, outcomes, population focus, study design, and type of prevention research. All results are based on that manual coding.

RESULTS

Taxonomy updates resulted in a slight increase, from an average of 16.7% to 17.6%, in the proportion of prevention research awards for 2012‒2017; there was a further increase to 20.7% in 2019. Most of the leading risk factors for death and disability in the U.S. were observed as an exposure or outcome in <5% of prevention research projects in 2019 (e.g., diet, 3.7%; tobacco, 3.9%; blood pressure, 2.8%; obesity, 4.4%). Analysis of existing data became more common (from 36% to 46.5%), whereas randomized interventions became less common (from 20.5% to 12.3%). Randomized interventions addressing a leading risk factor in a minority health or health disparities population were uncommon.

CONCLUSIONS

The number of new NIH awards classified as prevention research increased to 20.7% in 2019. New projects continued to focus on observational studies and secondary data analysis in 2018 and 2019. Additional research is needed to develop and test new interventions or develop methods for the dissemination of existing interventions, which address the leading risk factors, particularly in minority health and health disparities populations.

Trajectories of Current and Predicted Satisfaction With One's Life Following a Cancer Diagnosis

Background

Poor physical and mental health is common among cancer survivors, but little is known about how cancer influences life satisfaction and expectations about one's future, both of which may subsequently influence health decisions and outcomes.

Purpose

The current study examined how a cancer diagnosis influences current and predicted future life satisfaction in seven domains, including family, finances, work, and health.

Methods

We leveraged data from three waves of the Midlife in the United States study (N = 6,389) and examined the relation between new and past cancer diagnoses on satisfaction using generalized estimating equations. We also compared participants' predicted satisfaction to the actual satisfaction they reported at later waves of data collection, and examined whether concordance between the two differed by cancer history.

Results

A cancer diagnosis was associated with a decline in satisfaction about one's present health and sex life, ps < .05, but satisfaction with all other domains remained steady or improved. In contrast, predictions about the future became and remained less optimistic than the predictions of those without cancer across all life domains except relationships with children, ps < .05. Within-subjects comparisons of predicted and actual satisfaction suggest those without a cancer history were optimistic in their predictions across all life domains except health whereas survivors were more accurate in their predictions.

Conclusions

Given the many ways in which expectations about the future can influence decision making, behavior, and health, survivors' attenuated optimistic outlooks may influence their health and well-being.

Moving beyond categorization to understand affective influences on real world health decisions

This paper provides an overview of affect and health decision-making research, with a focus on identifying gaps, opportunities, and challenges to guide future research. We begin by defining common categorical distinctions of affective processes that influence health decisions: integral (i.e., related to the decision) and incidental (i.e., normatively unrelated to the decision) influences, and current (experienced in the moment) and anticipated ("cognitive representations" of future affect) affect. We then summarize key discoveries within the most common categories of affective influences on health decision making: current integral affect, current incidental affect, and anticipated integral affect. Finally, we highlight research gaps, challenges, and opportunities for future directions for research aimed at translating affective and decision science theory to improve our understanding of, and ability to intervene upon, health decision making.

Knowledge of and beliefs about palliative care in a nationally-representative U.S. sample

Palliative care aims to improve quality of life for people with serious illness and their families. One potential barrier to palliative care uptake is inaccurate knowledge and/or negative beliefs among the general population, which may inhibit early interest in, communication about, and integration of palliative care following subsequent illness diagnosis. We explored knowledge and beliefs about palliative care among the general public using nationally-representative data collected in 2018 as part of the cross-sectional Health Information National Trends Survey. Only individuals who had heard of palliative care (n = 1,162, Mage = 51.8, 64% female) were queried on knowledge and beliefs. We examined whether self-assessed level of awareness of palliative care (i.e., knowing a little vs. enough to explain it) was associated with the relative likelihood of having accurate/positive beliefs, inaccurate/negative beliefs, or responding "don't know" to questions about palliative care. Respondents who indicated knowing a lot about palliative care had more accurate versus inaccurate knowledge than those who knew a little on only two of six items and more positive attitudes on only one of three items. In particular, respondents with greater awareness were equally likely to report that palliative care is the same as hospice and requires stopping other treatments, and equally likely to believe that palliative care means giving up and to associate palliative care with death. Those with higher awareness were less likely than those with lower awareness to respond "don't know," but greater awareness was not necessarily associated with having accurate or positive beliefs about palliative care as opposed to inaccurate or negative beliefs. Thus, even members of the general public who perceived themselves to know a lot about palliative care were often no less likely to report inaccurate knowledge or negative beliefs (versus accurate and positive, respectively). Findings suggest a need to improve awareness and attitudes about palliative care.

Toward a Conceptual Model of Affective Predictions in Palliative Care

CONTEXT

Being diagnosed with cancer often forces patients and families to make difficult medical decisions. How patients think they and others will feel in the future, termed affective predictions, may influence these decisions. These affective predictions are often biased, which may contribute to suboptimal care outcomes by influencing decisions related to palliative care and advance care planning.

OBJECTIVES

This study aimed to translate perspectives from the decision sciences to inform future research about when and how affective predictions may influence decisions about palliative care and advance care planning.

METHODS

A systematic search of two databases to evaluate the extent to which affective predictions have been examined in the palliative care and advance care planning context yielded 35 relevant articles. Over half utilized qualitative methodologies (n = 21). Most studies were conducted in the U.S. (n = 12), Canada (n = 7), or European countries (n = 10). Study contexts included end of life (n = 10), early treatment decisions (n = 10), pain and symptom management (n = 7), and patient-provider communication (n = 6). The affective processes of patients (n = 20), caregivers (n = 16), and/or providers (n = 12) were examined.

RESULTS

Three features of the palliative care and advance care planning context may contribute to biased affective predictions: 1) early treatment decisions are made under heightened emotional states and with insufficient information; 2) palliative care decisions influence life domains beyond physical health; and 3) palliative care decisions involve multiple people.

CONCLUSION

Biases in affective predictions may serve as a barrier to optimal palliative care delivery. Predictions are complicated by intense emotions, inadequate prognostic information, involvement of many individuals, and cancer's effect on non-health life domains. Applying decision science frameworks may generate insights about affective predictions that can be harnessed to solve challenges associated with optimal delivery of palliative care.

Awareness of Palliative Care among a Nationally Representative Sample of U.S. Adults

Background: Palliative care can alleviate symptom burden, reduce psychosocial distress, and improve quality of life for patients suffering from serious or life-threatening illnesses. However, the extent to which U.S. adults are aware of or understand the goals and benefits of palliative care is not well understood. Public awareness of palliative care is necessary to change norms and create demand, and as such, limited awareness may be a significant barrier to palliative care uptake. An assessment of current palliative care awareness in the United States is needed to inform the health care sector's improving palliative care communication and delivery. Objective: To examine the prevalence of palliative care awareness among a nationally-representative sample of U.S. adults and to identify sociodemographic and health-related characteristics associated with palliative care awareness. Design: Weighted data from the Health Information National Trends Survey (HINTS 5, Cycle 2 [2018], N = 3445) were used to produce frequencies of the characteristics, and associations with palliative care awareness were determined through multiple logistic regression. Results: An estimated 71% of U.S. adults reported having never heard of palliative care. Older individuals, those with higher educational attainment, women, and whites (vs. nonwhites) had greater odds of palliative care awareness. Conclusions: These data suggest there is limited awareness of palliative care in the United States, despite its documented benefits. Addressing this awareness gap is a priority to change norms around using palliative care services. Community- and population-based interventions are necessary to raise awareness and inform the public about palliative care.

Direct and indirect associations of cognitive reappraisal and suppression with disease biomarkers

OBJECTIVE

Habitual use of emotion regulation strategies may influence physical health. We examined whether the tendencies to employ cognitive reappraisal and suppression were associated with health biomarkers, and whether stress and sleep quality mediated these associations. Design & main outcome measures: Using data from the Biomarkers substudy (n = 1255) of the national Midlife in the U.S. Study, we tested the hypothesis that there would be indirect, but not direct, associations of cognitive reappraisal and suppression to biomarker indicators of multisystem physiological dysregulation, that is, allostatic load (AL). We computed the proportion of biomarkers in the highest risk quartile within seven biological systems, and summed these scores to compute AL. Associations with the biological systems were also examined separately.

RESULTS

Neither reappraisal nor suppression was directly associated with AL or biomarker function in the seven biological systems. Suppression was indirectly associated with higher AL and greater dysregulation in the inflammatory, metabolic, and hypothalamic-pituitary-adrenal systems via its relations to stress and sleep, p < 0.05. Reappraisal was indirectly associated with lower AL and less metabolic and inflammatory dysregulation, ps<0.05.

CONCLUSIONS

Suppression and reappraisal may have different downstream health effects via stress, sleep, and biomarker expression, suggesting malleable emotion regulation strategies may be an important intervention target.

Factors beyond Lack of Knowledge That Predict "I Don't Know" Responses to Surveys That Assess HPV Knowledge

Accurately assessing the public's knowledge about the human papilloma virus (HPV) and the HPV vaccine remains critical for informing health education interventions aimed at increasing vaccine uptake. Responding "don't know" (DK) to survey questions that assess knowledge is common and DK responders are often systematically different from other responders, resulting in potential for bias. This study aimed to advance our understanding of DK responding to HPV knowledge items. Data from the nationally representative Health Information National Trends Survey Wave 5 Cycle 1 (N = 2,034) were used. Information seeking about cancer, information avoidance, health-related self-efficacy, and several cancer beliefs were examined as predictors of DK responding to six items that assessed HPV knowledge. DKs represented nearly half of responses. Adjusting for demographic factors, lower health-related self-efficacy, and greater information avoidance, cancer-mortality salience, and perceived ambiguity were associated with more DK responding, ps < .05. Even participants with incorrect responses had greater health-related self-efficacy, and less information avoidance, perceived ambiguity, and cancer-mortality salience than those who responded with DK. DK responding to HPV knowledge items is common and reflects factors beyond insufficient knowledge or motivation. Addressing causes of DK responding may reduce bias and improve interventions informed by surveys.

Effects of Emotion on Medical Decisions Involving Tradeoffs

Risk perceptions for a disease can motivate use of medications that reduce disease risk. However, these medications are often accompanied by elevated risks for other adverse health effects, and perceived risk of these side effects may also influence decisions. Emotions experienced at the time of a decision influence risk judgments and decision making, and they may be important to examine in these tradeoff contexts. This study examined the effect of experimentally induced fear and anger on risk perceptions and willingness to use a hypothetical medical treatment that attenuates risk of one condition but increases the risk for another. Participants ( N = 1948) completed an induction of fear, anger, or neutral emotion and then read about a hypothetical medication that reduced risk for one health condition but increased risk for another, and they indicated their willingness to use it. Deliberative, experiential, and affective risk perceptions about both health conditions were measured, conditional on taking and not taking the medication. Fear condition participants were more willing to take the medication than those in the neutral condition (β = 0.14; P = 0.009; 95% confidence interval, 0.036-0.25). Fear also increased deliberative, experiential, and affective risk when conditioned on not using the medication, Ps < 0.05. In contrast, anger did not influence willingness to use the medication ( P = 0.22) and increased deliberative and affective risk of side effects when conditioned on using the medication ( P < 0.05). As one of the first studies to examine how emotion influences tradeoff decision making, these findings extend our understanding of how fear and anger influence such decisions.

Interventions to Engage Affective Forecasting in Health-Related Decision Making: A Meta-Analysis

Background

People often use affective forecasts, or predictions about how a decision will make them feel, to guide medical and health decision making. However, these forecasts are susceptible to biases and inaccuracies that can have consequential effects on decision making and health.

Purpose

A meta-analysis was performed to determine the effectiveness of intervening to address affective forecasting as a means of helping patients make better health-related choices.

Methods

We included between-subjects experimental and intervention studies that targeted variables related to affective forecasting (e.g., anticipated regret, anticipated affect) as a means of changing health behaviors or decisions. We determined the overall effect of these interventions on targeted affective constructs and behavioral outcomes, and whether conceptual and methodological factors moderated these effects.

Results

A total of 133 independent effect sizes were identified from 37 publications (N = 72,020). Overall, affective forecasting interventions changed anticipated regret, d = 0.24, 95% confidence interval (CI) (0.15, 0.32), p < .001, behavior, d = 0.29, 95% CI (0.13, 0.45), p < .001, and behavioral intentions, d = 0.19, 95% CI (0.11, 0.28), p < .001, all measured immediately postintervention. Interventions did not change anticipated positive and negative affect, and effects on intentions and regret did not extend to follow-up time points, ps > .05. Generally, effects were not moderated by conceptual model, intervention intensity, or behavioral context.

Conclusions

Affective forecasting interventions had a small consistent effect on behavioral outcomes regardless of intervention intensity and conceptual framework, suggesting such constructs are promising intervention targets across several health domains.

The interplay between feelings and beliefs about condoms as predictors of their use

OBJECTIVE

Negative feelings about condoms are a key barrier to their use. Using the behavioural affective associations model, we examined the joint effects of affective associations and cognitive beliefs about condoms on condom use.

DESIGN

In Study 1 (N = 97), students completed measures of their affective associations and cognitive beliefs about sex and condoms, sexual activity and condom use. In Study 2 (N = 171), a measure of behavioural intentions and condom selection task were added.

MAIN OUTCOME MEASURES

Condom use measured in Study 1 as (1) current condom use, and (2) willingness to use condoms; in Study 2 as: (1) behavioural intentions, (2) number of condoms selected.

RESULTS

Affective associations with sex and condoms were behaviour-specific, were directly associated with the respective behaviour, and mediated the relations of cognitive beliefs to behaviour, ps < .05. In Study 2, affective associations were associated with behavioural intentions and the number of condoms selected, ps < .05; cognitive beliefs were indirectly associated with these outcomes through affective associations, indirect effects: ps < .05.

CONCLUSIONS

Affective associations are a behaviour-specific and proximal predictor of condom use, mediating the effect of cognitive beliefs, suggesting they may be a particularly viable intervention target.

Designing a randomized controlled trial to evaluate a community-based narrative intervention for improving colorectal cancer screening for African Americans

OBJECTIVE

To describe the methodology of a 2-arm randomized controlled trial that compared the effects of a narrative and didactic version of the Witness CARES (Community Awareness, Reach, & Empowerment for Screening) intervention on colorectal cancer screening behavior among African Americans, as well as the cognitive and affective determinants of screening.

METHODS

Witness CARES targeted cognitive and affective predictors of screening using a culturally competent, community-based, narrative or didactic communication approach. New and existing community partners were recruited in two New York sites. Group randomization allocated programs to the narrative or didactic arm. Five phases of data collection were conducted: baseline, post-intervention, three-month, six-month, and qualitative interviews. The primary outcome was screening behavior; secondary outcomes included cognitive and affective determinants of screening.

RESULTS

A total of 183 programs were conducted for 2655 attendees. Of these attendees, 19.4% (N=516) across 158 programs (50% narrative; 50% didactic) were study-eligible and consented to participate. Half (45.6%) of the programs were delivered to new community partners and 34.8% were delivered at faith-based organizations. Mean age of the total sample was 64.7years and 75.4% were female.

CONCLUSION

The planned number of programs was delivered, but the proportion of study-eligible attendees was lower than predicted. This community-based participatory research approach was largely successful in involving the community served in the development and implementation of the intervention and study.

Perspectives on Palliative Care in Cancer Clinical Trials: Diverse Meanings from Multidisciplinary Cancer Care Providers

BACKGROUND

Palliative care (PC) is often misunderstood as exclusively pertaining to end-of-life care, which may be consequential for its delivery. There is little research on how PC is operationalized and delivered to cancer patients enrolled in clinical trials.

OBJECTIVE

We sought to understand the diverse perspectives of multidisciplinary oncology care providers caring for such patients in a teaching hospital.

METHODS

We conducted qualitative semistructured interviews with 19 key informants, including clinical trial principal investigators, oncology fellows, research nurses, inpatient and outpatient nurses, spiritual care providers, and PC fellows. Questions elicited information about the meaning providers assigned to the term "palliative care," as well as their experiences with the delivery of PC in the clinical trial context. Using grounded theory, a team-based coding method was employed to identify major themes.

RESULTS

Four main themes emerged regarding the meaning of PC: (1) the holistic nature of PC, (2) the importance of symptom care, (3) conflict between PC and curative care, and (4) conflation between PC and end-of-life care. Three key themes emerged with regard to the delivery of PC: (1) dynamics among providers, (2) discussing PC with patients and family, and (3) the timing of PC delivery.

CONCLUSION

There was great variability in personal meanings of PC, conflation with hospice/end-of-life care, and appropriateness of PC delivery and timing, particularly within cancer clinical trials. A standard and acceptable model for integrating PC concurrently with treatment in clinical trials is needed.

Sex Differences in the Association of Perceived Ambiguity, Cancer Fatalism, and Health-Related Self-Efficacy with Fruit and Vegetable Consumption

Adequate fruit and vegetable (FV) consumption is promoted as a means of preventing chronic health conditions, such as cardiovascular disease and cancer. This study investigated whether perceived ambiguity about cancer prevention recommendations, fatalistic beliefs about cancer, and health-related self-efficacy were associated with FV consumption and whether sex moderated these associations. Data from the five most recent waves (spanning 2011 to 2017) of the nationally representative Health Information National Trends Survey (N = 16,965) were used. Participants reported levels of perceived ambiguity, cancer fatalism, health-related self-efficacy, and daily FV consumption. Perceived ambiguity and cancer fatalism were negatively associated with FV consumption, ps <.001, whereas health-related self-efficacy was positively associated with FV consumption, b = 0.34, p < .001. Sex moderated these associations, ps <.05. Perceived ambiguity and cancer fatalism were more strongly associated with less FV consumption for men, bs < -0.31, ps <.001, than women, bs < -0.14, ps <.01. In contrast, health-related self-efficacy was more strongly associated with more FV consumption for women, b = 0.43, p < .001, than men, b = 0.26, p < .001. These results suggest that tailoring health messaging to target sex-specific barriers may improve their effectiveness.

Unpacking cancer patients' preferences for information about their care

OBJECTIVE

Patient-centered decision making requires cancer patients be actively involved and feel sufficiently informed about their care, but patients' preferences for information are often unrecognized or unmet by their oncologist, particularly for more distressing topics. This study examined cancer patients' preferences for information about three care-related topics: (1) diagnostic information, (2) treatment costs, and (3) prognosis. We tested whether factors known to influence information preferences (psychological distress, control preferences, and financial distress) were differently associated with information preferences for each topic.

METHODS

Cancer patients (N = 176) receiving ongoing treatment completed a questionnaire that assessed their out-of-pocket treatment costs, psychological distress, preferences for control over their medical decisions, and the amount of information they desired and received from their oncologists about the three topics.

RESULTS

Patients' preferences were less often met for treatment cost information than for the other topics, p < 0.001, with half wanting more cost information than they received. One-third of patients also wanted more prognostic information than they received. Patients' preferences for diagnostic information did not differ as a function of financial burden, distress, or control preferences, ps > 0.05. Preferences for cost information were greater among patients who preferred more control over their medical decisions, p = 0.016. Patients' preferences for prognostic information were greater among those desiring more control and with lower distress, ps < 0.05. Financial burden was not associated with information preferences.

CONCLUSION

Appreciating the variability in information preferences across topics and patients may aid efforts to meet patients' information needs and improve outcomes.

Increasing condom use by changing people's feelings about them: An experimental study

OBJECTIVE

Given the well-documented efficacy of condoms as a means of preventing pregnancy and sexually transmitted infection transmission, the low rates of condom use among young adults necessitates a deeper understanding of the factors that influence condom use decision making. The central purpose of the current study was to examine how experimentally manipulated affective associations with condoms influence subsequent behavior in a condom selection task, thereby providing support for a causal relation of affective associations to behavior in this health domain.

METHOD

Following a baseline assessment of cognitively based beliefs and affective associations, participants' (N = 171) affective associations with condoms were experimentally manipulated with an evaluative conditioning (EC) procedure. Images of condoms were paired repeatedly with positive or neutral affective stimuli. The key outcome measure was a behavioral choice task in which participants selected condoms upon completion of the experiment.

RESULTS

Participants in the positive condition reported more positive affective associations post-EC compared with those in the neutral condition, β = 0.33, p = .025, 95% CI (0.041, 0.63). For participants who regularly used condoms at baseline, those in the positive condition also selected significantly more condoms, RR = 1.39, p = .015, 95% CI (1.07, 1.83). This condition effect on behavior was partially mediated by the change in affective associations. There was no effect of condition on condom selection among participants who rarely used condoms at baseline.

CONCLUSION

The current study extends our theoretical understanding of the affect-behavior relation in the realm of condom use, and provides preliminary support for interventions that target affective associations with condoms.

Relations between negative affect and health behaviors by race/ethnicity: Differential effects for symptoms of depression and anxiety

OBJECTIVE

Health behaviors, including smoking and fruit and vegetable consumption, are both associated with psychological distress and vary by race/ethnicity. The relation of global psychological distress to behavior also varies by race/ethnicity, but the specific negative affective states responsible for this effect are not known. This study examined how the relation of feelings of depression and anxiety to health behaviors differs by race/ethnicity.

METHOD

Secondary data analysis of the HINTS nationally representative population survey was conducted. Survey participants reported their current symptoms of depression and anxiety, as well as smoking status and fruit and vegetable consumption. Survey weighted linear and logistic regression analyses were used to assess whether race/ethnicity moderated the relation of symptoms of depression and anxiety to smoking and fruit and vegetable consumption.

RESULTS

For symptoms of depression, but not anxiety, there was a significant interaction between race/ethnicity and psychological distress in predicting both smoking status and fruit and vegetable consumption. Greater depressive symptoms were related to a greater likelihood of smoking and lower fruit and vegetable consumption for White, but not Black respondents. For Hispanic respondents, depressive symptoms were associated with a greater likelihood of currently smoking, but were not associated with fruit and vegetable consumption.

CONCLUSION

The association between depressive symptoms and both smoking and fruit and vegetable consumption differs as a function of race/ethnicity. These findings have implications for understanding the extent to which negative affective states influence health behaviors across different racial/ethnic groups, and for developing interventions that effectively target smoking and fruit and vegetable consumption among different racial/ethnic subgroups.

Worry about skin cancer mediates the relation of perceived cancer risk and sunscreen use

Preventive health behaviors are believed to be motivated in part by a person's perception of risk for a particular health problem. Risk contains a cognitive component, beliefs about the chances of a health problem occurring, and an affective component, fear or worry about the health problem. Although both have been shown to influence behavior, the nature of their interrelation as an influence on behavior has not been examined. Data from the 2005 Health Information National Trends Survey, a US nationally-representative telephone survey was analyzed. Participants reported perceived absolute and comparative risk for skin cancer, feelings of worry about skin cancer, and sunscreen use behavior. Analyses examined main effects models for the relation between perceived risk, worry, and sunscreen use, as well as both moderated and mediated models. For both absolute and comparative risk, the relation between cognitively-based perceived risk for skin cancer and sunscreen use was fully mediated by feelings of worry, as evidenced by significant direct effects of worry (bs > 0.046, ps < 0.01) and indirect effects of risk through worry (bs > 0.19, ps < 0.01). When worry was included in the models, direct effects of risk perceptions were non-significant (bs < 0.11, ps < 0.10). No evidence was found for moderated effects of worry on the relation between risk and behavior. While cognitive risk appraisals do influence decision making and may be addressed by interventions, these findings demonstrate that affectively-based risk components play a key role in behavior regulation. Affectively-based risk might be an effective target for interventions and should be incorporated more fully in decision-making models.

Expression of rat aldehyde reductase AKR7A1: influence of age and sex and tissue-specific inducibility

The regulation of the aldo-keto reductase AKR7A1 was examined in the livers of male and female rats during development by using Western blots, and its contribution to carbonyl metabolism was assessed by using enzyme assays. Hepatic levels of AKR7A1 are low in fetal rats and rise to a peak at around 6 weeks of age in animals of both sexes. Higher levels of the enzyme are found in adult male rat liver than in adult female rat liver. The reductase, therefore, appears to be subject to sex-specific regulation. The effect of growth hormone in mediating this difference in expression was examined by using hypophysectomized animals whose serum growth hormone levels had been feminized by continuous administration. Results demonstrate that such treatment leads to a reduction in AKR7A1 expression. AKR7A1 was found to be constitutively expressed in rat tissues such as liver, kidney, small intestine, and testis, but it was not detected in nasal mucosa, skeletal muscle, heart, adrenal gland, brain, or spleen. However, AKR7A1 was inducible by the synthetic antioxidant ethoxyquin in liver, kidney, and small intestine, but not in the other tissues examined. These results show that levels of this important detoxication enzyme vary considerably according to age and sex and that dietary antioxidants can also influence its level in several tissues.

Three aldo-keto reductases of the yeast Saccharomyces cerevisiae

Saccharomyces cerevisiae is an industrially important yeast, which is also used extensively as a model eukaryote. The S. cerevisiae genome has been sequenced in its entirety and therefore represents an ideal organism in which to carry out functional analysis of genes. We have identified several open reading frames in the S. cerevisiae genome which show significant similarity to members of the aldo-keto reductase superfamily. The physiological roles of these gene products have not been previously determined, but their similarity to other enzymes suggests they may perform roles in carbohydrate metabolism and detoxification pathways. Cloning and expression of three of these enzymes has allowed their substrate specificities to be determined. Expression profiling and gene disruption analysis will allow potential roles for these enzymes within the cell to be examined.

Purification from rat liver of a novel constitutively expressed member of the aldo-keto reductase 7 family that is widely distributed in extrahepatic tissues

Antiserum raised against human aflatoxin B(1) aldehyde reductase 1 (hAFAR1) has been used to identify a previously unrecognized rat aldo-keto reductase (AKR). This novel enzyme is designated rat aflatoxin B(1) aldehyde reductase 2 (rAFAR2) and it characteristically migrates faster during SDS/PAGE than does the archetypal ethoxyquin-inducible rAFAR protein (now called rAFAR1). Significantly, rAFAR2 is essentially unreactive with polyclonal antibodies raised against rAFAR1. Besides its distinct electrophoretic and immunochemical properties, rAFAR2 appears to be regulated differently from rAFAR1 as it is expressed in most rat tissues and does not appear to be induced by ethoxyquin. Multiple forms of rAFAR2 have been identified. Anion-exchange chromatography on Q-Sepharose, followed by adsorption chromatography on columns of Matrex Orange A and Cibacron Blue, have been employed to purify rAFAR2 from rat liver cytosol. The Q-Sepharose chromatography step resulted in the resolution of rAFAR2 into three peaks of AKR activity, two of which were purified and shown to be capable of catalysing the reduction of 2-carboxybenzaldehyde, succinic semialdehyde, 4-nitrobenzaldehyde and 9,10-phenathrenequinone. The two most highly purified rAFAR2-containing preparations eluted from the Cibacron Blue column were 91 and 98% homogeneous. Analysis of these by SDS/PAGE indicated that the least anionic (peak CBA5) comprised a polypeptide of 37.0 kDa, whereas the most anionic (peak CBA6) contained two closely migrating polypeptides of 36.8 and 37.0 kDa; by contrast, in the present study, rAFAR1 was estimated by SDS/PAGE to be composed of 38.0 kDa subunits. Final purification of the 37 kDa polypeptide in CBA5 and CBA6 was accomplished by reversed-phase HPLC. Partial proteolysis of the two preparations of the 37 kDa polypeptide with Staphylococcus aureus V8 protease yielded fragments of identical size, suggesting that they represent the product of a single gene. Furthermore, the peptide maps from CBA5 and CBA6 differed substantially from that yielded by rAFAR1, indicating that they are genetically distinct from the inducible reductase. A peptide generated by CNBr digestion of the 37 kDa polypeptide from CBA6 was shown by Edman degradation to share 88% sequence identity with residues Tyr(168)-Leu(183) of rAFAR1. This provides evidence that the rat protein identified by its cross-reactivity with anti-hAFAR1 serum is an additional member of the AKR7 family.

Chemoprevention of aflatoxin B1 hepatocarcinogenesis by coumarin, a natural benzopyrone that is a potent inducer of aflatoxin B1-aldehyde reductase, the glutathione S-transferase A5 and P1 subunits, and NAD(P)H:quinone oxidoreductase in rat liver

Structurally diverse compounds can confer resistance to aflatoxin B1 (AFB1) hepatocarcinogenesis in the rat. Treatment with either phytochemicals [benzyl isothiocyanate, coumarin (CMRN), or indole-3-carbinol] or synthetic antioxidants and other drugs (butylated hydroxyanisole, diethyl maleate, ethoxyquin, beta-naphthoflavone, oltipraz, phenobarbital, or trans-stilbene oxide) has been found to increase hepatic aldo-keto reductase activity toward AFB1-dialdehyde and glutathione S-transferase (GST) activity toward AFB1-8,9-epoxide in both male and female rats. Under the conditions used, the natural benzopyrone CMRN was a major inducer of the AFB1 aldehyde reductase (AFAR) and the aflatoxin-conjugating class-alpha GST A5 subunit in rat liver, causing elevations of between 25- and 35-fold in hepatic levels of these proteins. Induction was not limited to AFAR and GSTA5: treatment with CMRN caused similar increases in the amount of the class-pi GST P1 subunit and NAD(P)H: quinone oxidoreductase in rat liver. Immunohistochemistry demonstrated that the overexpression of AFAR, GSTA5, GSTP1, and NAD(P)H:quinone oxidoreductase affected by CMRN is restricted to the centrilobular (periacinar) zone of the lobule, sometimes extending almost as far as the portal tract. This pattern of induction was also observed with ethoxyquin, oltipraz, and trans-stilbene oxide. By contrast, induction of these proteins by beta-naphthoflavone and diethyl maleate was predominantly periportal. Northern blotting showed that induction of these phase II drug-metabolizing enzymes by CMRN was accompanied by similar increases in the levels of their mRNAs. To assess the biological significance of enzyme induction by dietary CMRN, two intervention studies were performed in which the ability of the benzopyrone to inhibit either AFB1-initiated preneoplastic nodules (at 13 weeks) or AFB1-initiated liver tumors (at 50 weeks) was investigated. Animals pretreated with CMRN for 2 weeks prior to administration of AFB1, and with continued treatment during exposure to the carcinogen for a further 11 weeks, were protected completely from development of hepatic preneoplastic lesions by 13 weeks. In the longer-term dietary intervention, treatment with CMRN before and during exposure to AFB1 for a total of 24 weeks was found to significantly inhibit the number and size of tumors that subsequently developed by 50 weeks. These data suggest that consumption of a CMRN-containing diet provides substantial protection against the initiation of AFB1 hepatocarcinogenesis in the rat.

Cellular response to cancer chemopreventive agents: contribution of the antioxidant responsive element to the adaptive response to oxidative and chemical stress

Cancer chemopreventive agents can act by inhibiting either the acquisition of mutations or the neoplastic processes that occur subsequent to mutagenesis. Compounds that reduce the rate at which mutations arise, referred to as blocking agents, exert their effects largely through their ability to induce the expression of antioxidant and detoxification proteins. This is achieved by the transcriptional activation of a small number of genes that are co-regulated through the presence of an antioxidant responsive element (ARE) in their promoters. Blocking agents can cause gene induction by producing oxidative and/or chemical stress within the cell and, as the inducible proteins act to ameliorate the metabolic insult, the process represents a form of adaptive response. The transcription factors which mediate this response through the ARE are members of the basic leucine zipper superfamily. The mechanism whereby cells sense and respond to the chemical signal(s) generated by chemopreventive blocking agents is discussed.

Growth hormone- and testosterone-dependent regulation of glutathione transferase subunit A5 in rat liver

The class Alpha glutathione S-transferase (GST) subunit A5 is expressed in the livers of young male and female rats. After sexual maturation, this protein is no longer detectable in the livers of male rats, but is still expressed in female rats. We have previously demonstrated that the sexually dimorphic secretion of growth hormone regulates the levels of certain class Mu GSTs in rat liver, and this study was designed to investigate the hormonal regulation of GSTA5. Control and hypophysectomized rats of both sexes were used to study the role of growth hormone in the regulation of hepatic GSTA5; and the influence of testosterone on the expression of this same subunit was investigated in intact females and castrated males. Liver cytosols were subjected to SDS/PAGE and immunoblotting using antibodies directed towards rat (r)GSTA5, and to affinity purification on glutathione-Sepharose followed by reverse-phase HPLC in order to quantify the relative levels of rGSTA1, A2, A3, A4, M1 and M2 subunits. These analyses revealed that the expression of rGSTA5 is, indeed, regulated by both growth hormone and testosterone.

Regulation of rat glutathione S-transferase A5 by cancer chemopreventive agents: mechanisms of inducible resistance to aflatoxin B1

The rat can be protected against aflatoxin B1 (AFB1) hepatocarcinogenesis by being fed on a diet containing the synthetic antioxidant ethoxyquin. Evidence suggests that chemoprotection against AFB1 is due to increased detoxification of the mycotoxin by one or more inducible drug-metabolising enzymes. The glutathione S-transferase (GST) isoenzymes in rat liver that contribute to ethoxyquin-induced chemoprotection against AFB1 have been identified by protein purification. This approach resulted in the isolation of several heterodimeric class alpha GST, all of which contained the A5 subunit and possessed at least 50-fold greater activity towards AFB1-8,9-epoxide than previously studied transferases. Molecular cloning and heterologous expression of rat GSTA5-5 has led to the demonstration that it exhibits substantially greater activity for AFB1-8,9-epoxide than other rat transferases. The A5 homodimer can also catalyse the conjugation of glutathione with other epoxides, such as trans-stilbene oxide and 1,2-epoxy-3-(4'-nitrophenoxy)propane, and possesses high catalytic activity for the reactive aldehyde 4-hydroxynonenal. Western blotting has shown that the A5 subunit is not only induced by ethoxyquin but that it is also induced by other cancer chemopreventive agents, such as butylated hydroxyanisole, oltipraz, benzyl isothiocyanate, indole-3-carbinol and coumarin. In addition to GSTA5, we have identified a novel aflatoxin-aldehyde reductase (AFAR) that is similarly induced by ethoxyquin. However, immunoblotting has shown that GSTA5 and AFAR are not always co-ordinately regulated by chemoprotectors. In order to gain a better understanding of the mechanisms responsible for the induction of GSTA5 protein, the GSTA5 gene has been cloned. It was isolated on two overlapping bacteriophage lambda clones and found to be approximately 12 kb in length. The transcriptional start site of GSTA5 has been identified 228 bp upstream from the ATG translational initiation codon. Computer-assisted analysis of the upstream sequence has indicated the presence of a putative antioxidant responsive element (located between -421 and -429 bp) which may be responsible for the induction of GSTA5 by chemopreventive agents.

Protection conferred by selenium deficiency against aflatoxin B1 in the rat is associated with the hepatic expression of an aldo-keto reductase and a glutathione S-transferase subunit that metabolize the mycotoxin

Fischer 344 rats fed on a diet that is deficient in selenium are more resistant to the hepatocarcinogen aflatoxin B1 (AFB1) than those fed on a selenium-sufficient diet. Hepatic cytosol from either selenium-deficient Fischer 344 rats or Hooded Lister rats possesses a marked increase in both reductase activity toward AFB1-dialdehyde and glutathione S-transferase (GST) activity toward AFB(1)-8,9-epoxide than hepatic cytosol from selenium-sufficient rats. The elevation in hepatic AFB1-aldehyde reductase (AFAR) activity in selenium-deficient animals is accompanied by an increase of 11- and 15-fold in the levels of AFAR protein in liver cytosol from Fischer 344 and Hooded Lister rats, respectively. The amount of AFAR protein in selenium-sufficient and -deficient Fischer rats was modulated by treatment with N-acetylcysteine; this antioxidant reduced basal expression of AFAR but did not modulate the relative overexpression of AFAR during selenium deficiency. The enhanced capacity to conjugate glutathione with AFB(1)-8,9-epoxide in selenium-deficient livers from Fischer 344 and Hooded Lister rats is associated with a 5- and 7-fold increase, respectively, in the hepatic levels of the AFB1-metabolizing alpha-class GSTA5 subunit. The elevated levels of AFAR and GSTA5 protein in the selenium-deficient animals coincided with increases in the steady-state levels of their mRNAs. In selenium-deficient Fischer 344 rats, AFAR and GSTA5 were both found to be expressed throughout the centrilobular and midzonal areas of the liver lobule but were essentially absent from periportal hepatocytes. The effect of selenium insufficiency is pleiotropic, and it was also noted that the theta-class GSTT1 is overexpressed 3- and 10-fold in livers of selenium-deficient Hooded Lister and Fischer 344 rats. Inasmuch as GSTT1 is responsible for the metabolic activation of dihaloalkanes, selenium deficiency may increase the susceptibility of rats to mutagens such as dichloromethane.

Regulation of carbonyl-reducing enzymes in rat liver by chemoprotectors

Feeding rats on diets containing the synthetic antioxidants ethoxyquin, butylated hydroxyanisole, and oltipraz results in 15-, 9-, and 6-fold increases, respectively, in the hepatic levels of aflatoxin B1-dialdehyde reductase (AFAR) protein. By contrast, treatment of rats with either of the inducing agents phenobarbital or 3-methylcholanthrene results in an approximate increase of only 1.4-fold in the amount of AFAR in rat liver. Northern blotting has shown that these increases in levels of hepatic AFAR protein are accompanied by corresponding increases in AFAR mRNA. Immunodepletion of AFAR from rat liver extracts has revealed that AFAR makes a considerable contribution to carbonyl metabolism in livers from animals treated with synthetic antioxidants and that it is the major reductase that can utilize aflatoxin B1-dialdehyde as a substrate. The immunodepletion experiments also revealed the presence of at least one other inducible carbonyl-reducing enzyme that, like AFAR, can metabolize 9,10-phenanthraquinone. Carbonyl-reducing activity from rat liver has been resolved into six enzyme-containing peaks by anion-exchange chromatography on Q-Sepharose. This method has been used to show that, in addition to AFAR, two other rat liver carbonyl-reducing enzymes are induced by ethoxyquin, and that these are distinct from NAD(P)H: quinone oxidoreductase. Collectively, these data show that synthetic antioxidants can influence substantially the capacity of rat liver to metabolize reactive carbonyl-containing compounds.

Substrate specificity of an aflatoxin-metabolizing aldehyde reductase

The enzyme from rat liver that reduces aflatoxin B1-dialdehyde exhibits a unique catalytic specificity distinct from that of other aldo-keto reductases. This enzyme, designated AFAR, displays high activity towards dicarbonyl-containing compounds with ketone groups on adjacent carbon atoms; 9,10-phenanthrenequinone, acenaphthenequinone and camphorquinone were found to be good substrates. Although AFAR can also reduce aromatic and aliphatic aldehydes such as succinic semialdehyde, it is inactive with glucose, galactose and xylose. The enzyme also exhibits low activity towards alpha,beta-unsaturated carbonyl-containing compounds. Determination of the apparent Km reveals that AFAR has highest affinity for 9,10-phenanthrenequinone and succinic semialdehyde, and low affinity for glyoxal and DL-glyceraldehyde.

An ethoxyquin-inducible aldehyde reductase from rat liver that metabolizes aflatoxin B1 defines a subfamily of aldo-keto reductases

Protection of liver against the toxic and carcinogenic effects of aflatoxin B1 (AFB1) can be achieved through the induction of detoxification enzymes by chemoprotectors such as the phenolic antioxidant ethoxyquin. We have cloned and sequenced a cDNA encoding an aldehyde reductase (AFB1-AR), which is expressed in rat liver in response to dietary ethoxyquin. Expression of the cDNA in Escherichia coli and purification of the recombinant enzyme reveals that the protein exhibits aldehyde reductase activity and is capable of converting the protein-binding dialdehyde form of AFB1-dihydrodiol to the nonbinding dialcohol metabolite. We show that the mRNA encoding this enzyme is markedly elevated in the liver of rats fed an ethoxyquin-containing diet, correlating with acquisition of resistance to AFB1. AFB1-AR represents the only carcinogen-metabolizing aldehyde reductase identified to date that is induced by a chemoprotector. Alignment of the amino acid sequence of AFB1-AR with other known and putative aldehyde reductases shows that it defines a subfamily within the aldo-keto reductase superfamily.

The Saccharomyces cerevisiae MTS1 gene encodes a putative RNA-binding protein involved in mitochondrial protein targeting

Most proteins present in the mitochondrion are nuclear encoded, and are directed to the organelle by virtue of a targeting sequence at the N terminus of the precursor protein. Mitochondrial (mt) protein targeting appears to require several accessory proteins that recognise mt precursors both in the cytoplasm and at the mt surface. We describe here the use of yeast genetics to identify a protein that is required for mt protein targeting. Two yeast mutants (mts1 and mts2) were isolated as extragenic suppressors of a known targeting defect in the presequence of the beta-subunit of ATP synthase. We have cloned and sequenced the wild-type allele of one of these genes (MTS1) and shown that it encodes a member of a family of RNA-binding proteins that is essential for growth.

Watchers in the night: an anthropological look at sleep disorders

An anthropological point of view is introduced to explain the origin of sleep disorders. Four groups of sufferers are discussed: (1) Those that fail to maintain primary relationships; (2) those that feel increased vulnerability during the night; (3) those who have failed to separate or individuate; and (4) those who show a higher arousability than sound sleepers. A case example is offered for each group. A description of sleeping arrangements of the Kung San people of the Kalahari desert; speculations of the need for arousability in primitive society to prevent predators from attacking serve to bolster the view point. A theory that suggests that sleep disorders in children are caused by Western sleeping arrangements, encouraging mother and child to sleep apart, is challenged.

Adult agoraphobia and childhood separation anxiety: using children's literature to understand the link

Separation-anxiety stories are frequent in children's literature and have eight characteristic elements. Peter Rabbit is used as an early and very simple example. A case study follows which illustrates the fear of separating from the family in an adult agoraphobic. The Wizard of Oz is presented as a more expanded version of a separation-anxiety story. A case study follows which illustrates a woman's difficulty with maturity and separation. A review of the literature is made in which studies are cited which indicate a history of childhood-separation problems in adult agoraphobics. Studies also show that panic disorder in these patients is often precipitated by losses and separations. Studies also show that agoraphobics may have poor problem-solving skills. Children's stories may serve as a guide to children toward mastery of separation fear. A case study follows of a man who developed a panic disorder while watching E.T. E.T. is presented as a separation-anxiety story for the late 1900s. The paper concludes with a brief review of children's separation-anxiety stories and how they reflect broad cultural changes.

OmpR and EnvZ are pleiotropic regulatory proteins: positive regulation of the tripeptide permease (tppB) of Salmonella typhimurium

The tppB locus of Salmonella typhimurium encodes the anaerobically-induced tripeptide permease. We have demonstrated that expression of tppB requires the function of the ompR and envZ gene products, originally identified as positive regulatory proteins required for the osmotic regulation of porin expression. Significantly, tppB expression is not osmotically regulated. We have also identified three additional genes whose expression depends on OmpR. Thus OmpR and EnvZ serve a more general regulatory role than has previously been supposed. This study provides the first detailed genetic analysis of the ompB locus of S. typhimurium.