Crisis response planning rapidly reduces suicidal ideation among U.S. military veterans receiving massed cognitive processing therapy for PTSD

Posttraumatic stress disorder (PTSD) is common among U.S. military veterans and is associated with increased risk of suicidal thoughts and behaviors. Crisis response planning (CRP), a brief safety planning-type intervention, has been shown to rapidly reduce suicidal ideation and suicide attempts in emergency and acute care settings. CRP's effectiveness when combined with trauma-focused therapies remains unknown. In this randomized pragmatic clinical trial with one-year follow-up, 157 U.S. military personnel and veterans were randomly assigned to receive CRP or self-guided safety planning (SP) prior to beginning massed cognitive processing therapy (CPT) for PTSD. Among 51 (32.5 % of sample) participants endorsing suicidal ideation at baseline, reductions in the severity of suicidal ideation were significantly larger and faster in CRP (F(11,672)= 15.8, p < .001). Among 106 participants denying suicidal ideation at baseline, 8.5 % of CRP participants versus 11.9 % of SP participants (OR=0.69, 95 % CI=0.19-2.52) reported new-onset suicidal ideation during any follow-up assessment. PTSD symptoms significantly reduced over time with no differences between groups. Results support the effectiveness of CRP for rapidly reducing suicidal ideation and managing suicide risk during outpatient treatment for PTSD.

Project Safe Guard: Challenges and opportunities of a universal rollout of peer-delivered lethal means safety counseling at a US military installation

INTRODUCTION

The US Department of Defense recommends lethal means safety counseling (LMSC) to promote firearm injury prevention via secure storage of personal firearms. We describe the rollout of a universal, peer-delivered adaptation of Project Safe Guard (PSG)-a brief, single-session LMSC discussion-at a US Space Force installation.

METHOD

Program evaluation data were collected via anonymous, voluntary, and online surveys. Of approximately 862 eligible active-duty service members and embedded civilians, 324 completed the preprogram survey and 68 and 37 completed the 1- and 2-month follow-ups, respectively.

RESULTS

At preprogram, 69.1% agreed that peer-delivered LMSC is appropriate. After rollout, 100% of the 222 firearm locking devices available to service members were requested from the on-base Violence Prevention Integrator. The effectiveness of PSG was indeterminable due to the low survey response rates.

CONCLUSIONS

Despite strong preprogram support for peer-delivered LMSC and behavioral indicators of secure firearm storage (e.g., firearm locking device requests), several challenges limited the uptake and evaluability of the PSG program in this naturalistic environment, including military survey fatigue and competing mission priorities. Additional work is needed to determine the effectiveness of peer-delivered LMSC in a military context. Sustained base support and military-civilian collaborations will be critical.

Military community engagement to prevent firearm-related violence: adaptation of project safe guard for service members

BACKGROUND

Suicide, especially by firearm, remains a leading cause of death in military populations in the USA. Reducing access to firearms, especially during high risk times, may help prevent suicide and other forms of violence. The purpose of this study was to adapt a promising existing lethal means safety intervention (Project Safe Guard, PSG) for cross-cutting violence prevention and peer support in active-duty service communities using community engagement methods.

METHODS

A two-pronged community-engaged research approach was employed, including the Community Translation (CT) process that engaged 15 Service Members from one installation to help adapt PSG successfully. In addition, qualitative data was collected from 40 active-duty service members and military violence prevention specialists through in-depth interviews and focus group discussions.

RESULTS

Qualitative data and CT feedback led to site-specific PSG adaptations. Participants emphasized the importance of peer-to-peer discussions and highlighted resource allocation, leadership support, and stigma on firearm ownership as potential implementation challenges.

CONCLUSIONS

Findings demonstrate the feasibility of community-engaged research to adapt lethal means safety interventions within military populations. PSG implementation should consider resource allocation, leadership support, and addressing stigma. This study has implications for future policies and standards for performing research on sensitive topics, particularly among military populations.

'Whether it's your weapon or not, it's your home': US military spouse perspectives on personal firearm storage

INTRODUCTION

In the USA, an estimated 45% of veterans personally own firearms. Firearm access increases the risk of suicide, so suicide prevention efforts in the US Department of Defense (DoD) focus on lethal means safety, including reducing firearm access. Spouse input may enhance effective messaging and intervention delivery of lethal means safety. This study used qualitative methods to explore the perspectives of military spouses or partners on personal firearm storage, including at-home decisions, on-base storage and existing messaging from the DoD.

MATERIALS AND METHODS

Qualitative data were obtained using 1:1 interviews and focus groups with spouses/partners of US military service members (active duty, Reserve, National Guard, recently separated from the military) and representatives from military support organisations. Sessions focused on personal firearm storage (at home or on military installations) and military messaging around secure firearm storage and firearm suicide prevention. Data were analysed using a team-based, mixed deductive-inductive approach.

RESULTS

Across 56 participants (August 2022-March 2023), the themes were variability in current home firearm storage and spousal participation in decision-making; uncertainty about firearm storage protocols on military installations; mixed awareness of secure firearm storage messaging from the military; and uncertainty about procedures or protocols for removing firearm access for an at-risk person.

CONCLUSION

US military spouses are important messengers for firearm safety and suicide prevention, but they are currently underutilised. Tailored prevention campaigns should consider spousal dynamics and incorporate education about installation procedures.

Group brief cognitive behavioral therapy for suicide prevention compared to dialectal behavior therapy skills group for military service members: a study protocol of a randomized controlled trial

BACKGROUND

Suicide is a pressing matter for the military. Not only does it pose a health risk, but suicide also compromises operational readiness. Despite provision of suicide prevention clinical best practices, the Department of Defense suffers several challenges (e.g., clinician shortages) limiting the agency's ability to effectively respond to service member suicide. Implementation of evidence-based suicide-specific group therapy is a possible solution to service member well-being needs and system challenges. Service members can also gain coping skills useful beyond managing suicidal thoughts and behaviors.

METHODS

This 2-arm non-inferiority randomized controlled trial compares a group therapy format of Brief Cognitive Behavioral Therapy (i.e., G-BCBT) with Dialectical Behavior Therapy (DBT) Skills Group. Both therapies are delivered in-person at a United States Naval Medical Center. Participants (N = 136) are active-duty service members with recent suicidal thoughts or suicidal behavior. Evaluation features electronically delivered questionnaires at baseline, after each treatment session, and at 3- and 6-month follow-up.

DISCUSSION

The primary outcome concerns G-BCBT impacts on suicidal ideation. Secondary outcomes of interest are suicide attempt, psychological distress (e.g., symptoms of depression, anxiety), and self-regulatory skills (e.g., emotion regulation). We also examine self-regulatory skills as treatment moderators. Clinical trial strengths and limitations are reviewed.

TRIAL REGISTRATION

This study was registered at Clinicaltrials.gov (protocol NCT05401838).

Does Suicide Risk Screening Improve the Identification of Primary Care Patients Who Will Attempt Suicide Versus Depression Screening Alone?

OBJECTIVE

The effectiveness of suicide risk screening relative to depression screening alone among primary care patients has not been tested rigorously. This study compared the performance of multiple depression screening methods (Patient Health Questionnaire [PHQ]-2, PHQ-8, and PHQ-9) and multiple suicide risk screening methods (PHQ-9 item 9 and suicide-focused screening of "thoughts of killing yourself" during the entire lifespan, within the past month, and within the past week) in a convenience sample of primary care patients.

METHODS

A total of 2,744 patients (military personnel, family members, and retirees) from six military primary care clinics completed the PHQ-9 and screening for suicidal ideation (SI) during routine clinic visits. Follow-up phone interviews were conducted for one year post-baseline to assess the incidence of suicide attempts, the study's primary outcome. Sensitivity, specificity, accuracy, and F1 statistics were calculated for each screening method for identifying patients who attempted suicide.

RESULTS

More than 65% of patients who screened positive for SI also screened positive for depression on the PHQ-9. Depression screening with the PHQ-9 correctly identified more patients who attempted suicide during follow-up than the PHQ-2, past week SI, and past month SI. The PHQ-9 correctly identified more patients who attempted suicide within 3 months than lifetime SI, but lifetime SI correctly identified more patients who attempted suicide within 6 and 12 months.

CONCLUSION

Depression screening with the PHQ-9 was the most effective strategy for identifying patients who attempted suicide in the near term. Universal suicide risk screening is unlikely to meaningfully improve identification of higher-risk patients beyond PHQ-9 depression screening.

Impact of the COVID-19 Pandemic on Indicators of Psychological Health and Suicidal Ideation Within an Active Duty U.S. Military Population

INTRODUCTION

The COVID-19 pandemic has had a significant impact on the psychological health of individuals. The pandemic has contributed to increased anxiety, elevated rates of depression, and worsening suicidal ideation among civilians. Reported rates of burnout are also elevated as employees and employers adapted to ever-changing work environments, finding it increasingly difficult to maintain a work-life balance. The objective of this study is to determine how the COVID-19 pandemic impacted the psychological health and rates of suicidal ideation of active duty military personnel in the USA.

MATERIALS AND METHODS

A total of 2055 military personnel and military-adjacent employees stationed at a U.S. Air Force base completed a self-report survey that was administered six times from January 2020 to December 2021. Validated scales assessed measures of psychological health and suicidal ideation. General Estimating Equations were used to examine how indicators of time and psychological health predicted suicidal ideation in a military population.

RESULTS

Life satisfaction, happiness, feeling life is worthwhile, depression severity, and suicidal ideation did not statistically change across the six time points. Worry (P < .01) and depression (P < .001) did decrease significantly, while burnout (P = .01) significantly increased across these time points. Feeling life is worthwhile significantly predicted reduced suicidal ideation (B = -.19; SE = 0.05), while depression (B = 0.11; SE = 0.03), depression severity (B = 0.24; SE = 0.05), worry (B = 0.06; SE = 0.02), and burnout (B = 0.15; SE = 0.07) predicted increased suicidal ideation.

CONCLUSIONS

The rates of depression and worry decreased throughout the pandemic for those in the study while rates of suicidal ideation remained constant, demonstrating the potential resilience of military personnel and military-adjacent employees in response to the COVID-19 pandemic. However, burnout increased and significantly predicted elevated rates of suicidal ideation, highlighting the importance of focusing on reducing workplace stressors for military personnel.

Firearm locking device preferences among firearm owners in the USA: a systematic review

BACKGROUND

Preventing firearm-involved injuries is a critical public health priority. Firearm locking devices can prevent firearm injuries, such as suicide and unintentional shootings, as well as theft. Various firearm locking devices exist; however, little is known about firearm owners' preferred locking devices for secure firearm storage. In this systematic review, we examined existing literature on preferred locking devices for secure storage of personal firearms among United States (US) firearm owners with the purpose of understanding practical implications and needs for future research.

METHODS

We searched 8 major databases, as well as the grey literature, for English-language sources published on or before January 24, 2023, that empirically examined firearm locking device preferences. Following PRISMA guidelines, coders independently screened and reviewed 797 sources using pre-determined criteria. Overall, 38 records met inclusion criteria and were included in this review.

RESULTS

The majority of studies measure and report on participant use of various types of locking devices, but few go on to measure preference between device options and the attributes and features that may contribute to an individual's preference. Included studies suggest that a preference for larger devices, such as lockboxes and gun safes, may exist among US firearm owners.

CONCLUSIONS

Review of included studies suggests that current prevention efforts may not be aligned with firearm owners' preferences. Additionally, findings from this systematic review emphasize the need for additional methodological rigorous research to understand firearm locking device preferences. Expanded knowledge in this area will result in actionable data and foundational best practices for programming that encourages behavior change concerning secure storage of personal firearms to prevent injury and death.

Rapid intensification of suicide risk preceding suicidal behavior among primary care patients

BACKGROUND

Approximately half of those who attempt suicide report experiencing suicidal ideation and suicidal planning in advance; others deny these experiences. Some researchers have hypothesized that rapid intensification is due to past suicidal ideation and/or behaviors that are "mentally shelved" but remain available for rapid access later.

METHOD

To evaluate this hypothesis, we examined (a) temporal sequencing of suicidal ideation, suicidal planning, and suicidal behavior, and (b) speed of emergence of suicidal behavior in a prospective cohort study of 2744 primary care patients.

RESULTS

Of 52 patients reporting suicidal behavior during follow-up, 20 (38.5%) reported suicidal ideation and planning prior to their suicidal behavior, 23 (44.2%) reported suicidal ideation but not planning, and nine (17.3%) denied both suicidal ideation and planning. Over half (n = 30, 57.7%) reported the onset of suicidal ideation and/or planning on the same day as or after their suicidal behavior (i.e., rapid intensification). Rapid intensification was not associated with increased likelihood of reporting recent or past suicidal ideation, planning, or behaviors, suggesting rapid intensification does not depend on prior experience with suicidal ideation and/or behaviors.

CONCLUSION

Detecting primary care patients at risk for this form of suicidal behavior may be limited even with universal suicide risk screening.

Assessment of Firearm Storage Practices in the US, 2022

IMPORTANCE

Secure firearm storage may help reduce firearm injury and death. Broad implementation requires more granular assessments of firearm storage practices and greater clarity on circumstances that may prevent or promote the use of locking devices.

OBJECTIVE

To develop a more thorough understanding of firearm storage practices, obstacles to using locking devices, and circumstances in which firearm owners would consider locking unsecured firearms.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional, nationally representative survey of adults residing in 5 US states who owned firearms was administered online between July 28 and August 8, 2022. Participants were recruited via probability-based sampling.

MAIN OUTCOMES AND MEASURES

Firearm storage practices were assessed via a matrix provided to participants in which firearm-locking devices were described both via text and images. Locking mechanisms (key/personal identification number [PIN]/dial vs biometric) were specified for each type of device. Obstacles to the use of locking devices and circumstances in which firearm owners would consider locking unsecured firearms were assessed via self-report items developed by the study team.

RESULTS

The final weighted sample included 2152 adult (aged ≥18 years), English-speaking firearm owners residing in the US; the sample was predominantly male (66.7%). Among the 2152 firearm owners, 58.3% (95% CI, 55.9%-60.6%) reported storing at least 1 firearm unlocked and hidden, with 17.9% (95% CI, 16.2%-19.8%) reporting storing at least 1 firearm unlocked and unhidden. Gun safes were the most frequently used device both among participants who use keyed/PIN/dial locking mechanisms (32.4%; 95% CI, 30.2%-34.7%) and those who use biometric locking mechanisms (15.6%; 95% CI, 13.9%-17.5%). Those who do not store firearms locked most frequently noted a belief that locks are unnecessary (49.3%; 95% CI, 45.5%-53.1%) and a fear that locks would prevent quick access in an emergency (44.8%; 95% CI, 41.1%-48.7%) as obstacles to lock usage. Preventing access by children was the most often reported circumstance in which firearm owners would consider locking unsecured firearms (48.5%; 95% CI, 45.6%-51.4%).

CONCLUSIONS AND RELEVANCE

In this survey study of 2152 firearm owners, consistent with prior research, unsecure firearm storage was common. Firearm owners appeared to prefer gun safes relative to cable locks and trigger locks, indicating that locking device distribution programs may not match firearm owners' preferences. Broad implementation of secure firearm storage may require addressing disproportionate fears of home intruders and increasing awareness of the risks associated with household firearm access. Furthermore, implementation efforts may hinge on broader awareness of the risks of ready firearm access beyond unauthorized access by children.

An empirical investigation of the distinction between passive and active ideation: Understanding the latent structure of suicidal thought content

INTRODUCTION

Although the distinction between passive and active suicidal ideation is well accepted by suicide researchers and clinicians, there has been very little empirical investigation into this distinction. The current study addressed this gap by examining the latent structure of suicidal ideation based on thought content.

METHOD

Participants from two distinct samples of U.S. adults (n1 = 6200; n2 = 10,625) completed a self-report assessment of eight commonly experienced suicidal thoughts using the Self-Injurious Thoughts and Behaviors Interview-Revised. Exploratory structural equation modeling was used to examine the latent structure of suicidal thoughts.

RESULTS

The two-factor model demonstrated significantly better fit than the one-factor solution across both samples. Thoughts typically classified as passive ideation strongly loaded onto one factor, whereas thoughts typically classified as active ideation loaded onto the second factor. The two factors were highly correlated and some suicidal thoughts exhibited meaningful cross-loading.

CONCLUSION

Our results suggest that passive and active ideation are two distinct constructs. Although they often co-occur, passive and active ideation are not nested constructs and should not be viewed as gradients of one underlying construct. Our findings suggest that at a minimum both passive and active ideation should be included in all suicide risk assessments and screenings.

Burnout, Surface Acting, and Suicidal Ideation Among Military Personnel: Results of a Longitudinal Cohort Study

Introduction: Chronic life stressors are positively correlated with suicidal ideation and suicidal behaviors among military personnel. Surface acting, a strategy that involves hiding or faking one's emotional state to match organizational expectations dictating when and how to express emotions, contributes to burnout and increased emotional distress. Because surface acting involves a form of emotional suppression, frequent use of surface acting may also contribute to suicidal ideation. Methods: One thousand seven-hundred fifty-four military personnel stationed at a U.S. military installation completed a self-report survey repeatedly administered 6 times from January 2020 to December 2021. Survey items assessed suicidal ideation, surface acting, burnout, and depression. Results: Burnout and surface acting were significantly correlated with severity of suicidal ideation. When depression was added as a covariate, surface acting but not burnout remained a statistically significant correlate of suicidal ideation. Discussion: Surface acting, a job-specific form of emotional suppression, may increase suicide risk among military personnel. Creating opportunities for military personnel to appropriately express their emotional states could mitigate suicide risk in this population.

Scores on the suicide cognitions scale-revised (SCS-R) predict future suicide attempts among primary care patients denying suicide ideation and prior attempts

BACKGROUND

Approximately half of patients who attempt or die by suicide screened negative for suicidal ideation during their most recent medical visit. Maladaptive beliefs and schemas can increase cognitive vulnerability to suicidal behavior, even among patients without recent or past suicidal thoughts and behaviors. Assessing these beliefs could improve the detection of patients who will engage in suicidal behavior after screening negative for elevated suicide risk.

METHODS

Primary care patients who completed the Patient Health Questionnaire-9 and the Suicide Cognitions Scale-Revised (SCS-R) during routine clinic visits and denied suicidal ideation at baseline (N = 2417) were included in the study sample. Suicidal behaviors during the 12 months after baseline were assessed. Logistic regression analyses examined the association of baseline SCS-R scores with later suicidal behavior.

RESULTS

In both univariate and multivariate analyses, SCS-R total scores were associated with significantly increased risk of suicidal behavior within 90, 180, and 365 days post-baseline. Results were unchanged when patients who reported prior suicidal behavior were excluded (N = 2178). In item-level analyses, all 16 SCS-R items significantly differentiated patients with and without follow-up suicidal behavior.

LIMITATIONS

Study limitations included missing follow-up data, restriction of sample to U.S. military medical beneficiaries, and inability to assess representativeness of the sample relative to the full primary care population.

CONCLUSIONS

SCS-R scores are elevated among patients who attempt suicide after denying both suicidal ideation and prior suicide attempts, suggesting the scale may reflect enduring suicide risk. The SCS-R could enhance suicide risk screening and assessment.

Suicide Intervention Practices: What Is Being Used by Mental Health Clinicians and Mental Health Allies?

OBJECTIVE

Implementation of evidence-based suicide prevention is critical to prevent death by suicide. Contrary to previously held beliefs, interventions including contracting for safety, no-harm contracts, and no-suicide contracts are not best practices and are considered contraindicated. Little is known about the current use of best practices and contraindicated interventions for suicide prevention in community settings.

METHODS

Data were collected from 771 individuals enrolled in a suicide prevention training. Both mental health clinicians (n = 613) and mental health allies (e.g., teachers, first responders) (n = 158) reported which best practices (i.e., safety plan, crisis response plan) and contraindicated interventions (i.e., contracting for safety, no-harm contract, no-suicide contract) they use with individuals who presents with risk for suicide.

RESULTS

The majority of both mental health clinicians (89.7%) and mental health allies (67.1%) endorsed using at least one evidence-based practice. However, of those who endorsed using evidence-based interventions, ∼40% of both mental health clinicians and allies endorsed using contraindicated interventions as well.

CONCLUSION

Contraindicated interventions are being used at high rates and suicide prevention trainings for evidence-based interventions should include a focus on de-implementation of contraindicated interventions. This study examined only a snapshot of what clinicians and allies endorsed using. Additional in depth information about each intervention and when it is used would provide helpful information and should be considered in future studies. Future research is needed to ensure only evidence-based interventions are being used to help prevent death by suicide.Highlights:The majority of both mental health clinicians and mental health allies use evidence-based practices for suicide prevention. This indicates good implementation rates of evidence-based interventions for suicide prevention.Approximately 40% of both mental health clinicians and mental health allies who endorsed using evidence-based practices for suicide preventions also endorsed using contraindicated interventions.A focus on de-implementation of contraindicated suicide interventions is warranted and should be part of the focus on suicide prevention efforts.

Disentangling subjective symptom complaints and objective cognitive performance in veterans: Impact of posttraumatic stress disorder and lifetime traumatic brain injury burden

Self-reported histories of mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD) symptoms are prevalent among post-9/11 veterans. Both are associated with subjective and often overlapping symptom complaints, but variably with objective neuropsychological test performances. These outcomes are seldom explored in relation to lifetime mTBI burden. This cross-sectional study examined associations of PTSD and lifetime mTBI with subjective (persistent symptoms after concussion and cognitive complaints) and objective (performances across five cognitive domains) measures among 46 veterans. Within this sample, 20 veterans had Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) confirmed PTSD (PTSD+), whereas 26 demographically-similar participants did not meet criteria (PTSD-). The Boston Assessment of Traumatic Brain Injury-Lifetime (BAT-L) yielded total mTBI scores ranging from 0 to 8. Regressions showed PTSD was associated with increased subjective symptoms/cognitive complaints, along with reduced verbal fluency, visuospatial memory, and processing speed performances. Lifetime mTBI burden was associated with subjective symptoms, but not with objective cognitive test performance, after controlling for PTSD. No significant interactions were observed. Exploratory correlations suggested that all PTSD symptom clusters were generally associated with the subjective and objective measures. However, fewer significant associations emerged within the PTSD+/- groups separately, with each group yielding somewhat different patterns of relationships. PTSD and increasing mTBI burden are consistently associated with negative subjective symptoms, including cognitive complaints. Each condition likely explains some degree of unique variance in symptom reporting. PTSD is associated with poorer objective cognition on some tasks, including processing speed, executive functioning, and learning/memory. Implications are explored.

Impact of Treatment Setting and Format on Symptom Severity Following Cognitive Processing Therapy for Posttraumatic Stress Disorder

Preliminary data suggest cognitive processing therapy (CPT) significantly reduces posttraumatic stress disorder (PTSD) symptom severity among military personnel and veterans when delivered over 12 days and combined with daily recreational activities (Bryan et al., 2018). The present study aimed to examine how therapy pace (i.e., daily vs. weekly sessions) and setting (i.e., clinic vs. recreational) impacts change in PTSD symptom severity. Forty-five military personnel and veterans diagnosed with PTSD chose to receive CPT (a) daily at a recreational facility with recreational programming, (b) daily on a university campus without recreational programming, and (c) weekly on a university campus without recreational programming. PTSD symptom severity was assessed with the Clinician Administered PTSD Scale for DSM-5 (CAPS-5) and the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5). Reductions in CAPS-5 and PCL-5 scores were large and statistically significant across all three settings (Cohen's ds > 2.1). As compared to reductions in CAPS-5 and PCL-5 scores in daily therapy at a recreational facility (CAPS-5: d = 1.63-2.40; PCL-5: d = 1.99-2.17), reductions in CAPS-5 and PCL-5 scores were significantly larger in daily therapy on campus, CAPS-5: t(80) = -2.9, p = .005, d = 2.23-2.69; PCL-5: t(78) = 2.6, p = .010, d = 2.54-4.43, but not weekly therapy on campus, CAPS-5: t(80) = 0.2, p = .883, d = 1.04-2.47; PCL-5: t(78) = 1.0, p = .310, d = 1.77-3.44. Participants receiving daily therapy on campus and weekly therapy on campus also had higher rates of clinically significant improvement and good end-state functioning. Results support the effectiveness of CPT across multiple treatment settings and formats and suggest that daily CPT may be less effective when delivered in combination with recreational activities.

Development of the Self-Injury Risk Assessment Protocol for Corrections (SIRAP-C)

OBJECTIVE

We developed the Self-Injury Risk Assessment Protocol for Corrections (SIRAP-C) to meet legal mandates for self-directed violence (SDV) risk assessment standards in correctional settings. We focused on two empirical aims: (1) factor structure and internal consistency and (2) subscale associations with SDV and intervention recommendation outcomes.

HYPOTHESES

We expected a multifactorial SIRAP-C structure with acceptable internal consistency. We further expected SIRAP-C subscales would distinguish history of SDV events while incarcerated, current SDV event category, and treatment recommendation.

METHOD

We drew electronic health record data for adult incarcerated persons (N = 3,929) from state Division of Prisons records from 2016 to 2020. Clinical records included demographic and correctional institutional information, as well as SIRAP-C records. Factor analyses assessed Aim 1. Regression models tested Aim 2.

RESULTS

Factor analyses supported a seven-factor SIRAP-C structure (27 items) comprising Depressive Symptoms, Reasons for Living, History of Self-Directed Violence, Current Suicidal Thinking, Family History of Self-Directed Violence, Coping Skills, and Social Connectedness. Subscales displayed acceptable internal consistency, with the exception of social connectedness in the confirmatory factor analysis subsample. Lower depressive symptoms and coping skills, as well as higher history of SDV, were associated with increased risk for a prior SDV assessment event while incarcerated. Lower depressive symptoms, current suicidal thinking, and coping skills and higher history of SDV marked worse risk for self-injurious behavior. Higher depressive symptoms and current suicidal thinking, as well as lower reasons for living, demarcated suicidal acts from self-injury. Higher history of SDV and lower coping skills indicated outpatient/residential treatment. Elevated depressive symptoms and history of SDV, as well as lower reasons for living and coping skills, were associated with inpatient hospitalization.

CONCLUSIONS

The SIRAP-C represents a promising clinical approach advancing correctional SDV risk assessment. We offer future research, policy, and implementation recommendations. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Assessment of Latent Subgroups With Suicidal Ideation and Suicidal Behavior Among Gun Owners and Non-Gun Owners in the US

IMPORTANCE

Firearm ownership is associated with increased risk for suicide.

OBJECTIVE

To examine patterns of associations among suicidal thoughts and behaviors among gun owners and non-gun owners in the US.

DESIGN, SETTING, AND PARTICIPANTS

In this survey study, cross-sectional online survey data were collected from March to April 2020 from US adults recruited via Qualtrics Panels. Quota sampling was used to approximate US census demographics.

MAIN OUTCOMES AND MEASURES

The primary outcomes were past-year passive suicidal ideation, active suicidal ideation, suicidal planning, suicidal behaviors, and nonsuicidal self-injury as measured by items from the Self-Injurious Thoughts and Behaviors Interview-Revised (SITBI-R). Simple latent class analysis (LCA) was used to assign participants to separate classes based on posterior probabilities, and multigroup LCA was used to assess whether the same construct was measured in specified groups.

RESULTS

Of 65 079 adults invited to participate, 10 625 (16.3%) completed the survey; 9153 responded "yes" or "no" to the firearm ownership item and were included in the analysis. Of these 9153 respondents (4695 [51.3%] male; mean [SD] age, 46.7 [16.8] years), 2773 (30.3%) reported owning a gun and 6380 (69.7%) reported not owning a gun. Compared with non-gun owners, gun owners were more likely to be male (1779 [64.2%] vs 2916 [45.7%]; χ21, 263.3; P < .001) and White (2090 [75.4%] vs 3945 [61.8%]; χ25, 232.9; P < .001) and to have served in the military (772 [27.8%] vs 609 [9.5%]; χ21, 571.4; P < .001). Five distinct patterns of SITBI-R item endorsement were extracted using simple LCA. Multigroup LCA indicated that the probability of SITBI-R item endorsement differed between gun owners and non-gun owners across subgroups. Among gun owners, the probability of past-month nonfatal suicide attempts was highest in class 4 (ranging from 16.8% for reaching out for help to 27.2% for starting, then changing one's mind). Gun owners in class 4 were characterized by high probabilities of endorsing thoughts about specific ways or methods to attempt suicide (100%) and preparatory behavior (100%). Among non-gun owners, the probability of nonfatal suicide attempts was highest in class 5 (ranging from 14.9% for reaching out for help to 29.7% for starting, then changing one's mind). Non-gun owners in class 5 were characterized by high probabilities of endorsing passive suicidal ideation (84.0%-100%), active suicidal ideation (86.7%-95.0%), and thoughts about specific ways or methods to attempt suicide (97.4%) and a specific place (92.1%) to attempt suicide.

CONCLUSIONS AND RELEVANCE

In this study, in subgroups with lower probabilities of suicide attempt, gun owners and non-gun owners showed similar patterns of suicide risk item endorsement, but when the probability of a suicide attempt increased, gun owners were less likely than non-gun owners to endorse passive and active suicidal ideation. These findings suggest that assessing a broader range of suicide risk indicators may improve risk detection.

Improving Suicide Risk Screening to Identify the Highest Risk Patients: Results From the PRImary Care Screening Methods (PRISM) Study

PURPOSE

Over 95% of patients who screen positive on the Patient Health Questionnaire-9 (PHQ-9) suicide risk item do not attempt or die by suicide, which could lead to unnecessary treatment and/or misallocation of limited resources. The present study seeks to determine if suicide risk screening can be meaningfully improved to identify the highest-risk patients.

METHODS

Patients eligible to receive medical treatment from the US Department of Defense medical system were recruited from 6 military primary care clinics located at 5 military installations around the United States. Patients completed self-report measures including the PHQ-9 and 16 items from the Suicide Cognitions Scale (SCS) during routine primary care clinic visits. Postbaseline suicidal behaviors (suicide attempts, interrupted attempts, and aborted attempts) were assessed by evaluators who were blind to screening results using the Self-Injurious Thoughts and Behaviors Interview.

RESULTS

Among 2,744 patients, 13 (0.5%) engaged in suicidal behavior in the 30 days after screening and 28 (1.0%) displayed suicidal behavior in the 90 days after screening. Multiple SCS items differentiated patients with suicidal behavior less than 30 days after screening positive for suicide risk. Augmenting the PHQ-9 suicide risk item with SCS items improved the identification of patients who were most likely to have suicidal behavior within a month of screening positive without sacrificing sensitivity.

CONCLUSION

Among primary care patients who screen positive for suicide risk on the PHQ-9, SCS items improved screening efficiency by identifying those patients who are most likely to engage in suicidal behavior within the next 30 days.

Depression, suicide risk, and declining to answer firearm-related survey items among military personnel and veterans

OBJECTIVES

To describe the characteristics of military personnel and veterans who decline to answer survey items asking about firearm availability at home, and to determine how these characteristics compare to those of military personnel and veterans who answered these items.

METHODS

Self-report surveys were administered to 2025 military personnel and veterans visiting a primary care clinic located at five military installations across the United States for a routine visit. Multinomial logistic regression was used to identify factors that distinguished participants with firearms at home, participants without firearms at home, and participants who declined answering.

RESULTS

In univariate analyses, participants who selected "refuse to answer" in response to an item asking about firearm access at home did not differ demographically from participants who selected "yes," but were significantly more likely to screen positive for depression and recent thoughts of death or self-harm. These differences were not statistically significant in multivariate analyses, however. Participants who selected "refuse to answer" or "yes" were significantly more likely than participants who selected "no" to be male, white, and previously deployed.

CONCLUSIONS

Military personnel and veterans who decline answering firearm-related survey items are indistinguishable from those who report having a firearm at home. Declining to answer firearm-related items is more common among those who screen positive for depression or recent thoughts of death or self-harm, but this association is statistically accounted for by demographic factors (i.e., male gender, white race).

The Airman's Edge Project: A Peer-Based, Injury Prevention Approach to Preventing Military Suicide

In light of data indicating military personnel are more likely to reach out to peers during times of need, peer-to-peer (P2P) support programs have been implemented for military suicide prevention. Often designed to reduce suicidal thoughts and behaviors by reducing mental health symptom severity, existing data suggest that P2P programs have little to no effect on mental health symptoms. Conceptualizing suicide prevention from an occupational safety and injury prevention perspective to promote positive health-related behavior change at both the group and individual level may enhance the effectiveness of P2P programs and military suicide prevention efforts more broadly. To illustrate these concepts, the present article provides an overview of the Airman’s Edge project, a P2P program design based upon the occupational safety and injury prevention model of suicide prevention, and describes a program evaluation effort designed to test the effectiveness of this approach.

The Marine Suicide Prevention and Intervention REsearch (M-SPIRE) study: A randomized clinical trial investigating potential treatment mechanisms for reducing suicidal behaviors among military personnel

Suicides within the U.S. Armed Forces remain elevated. Brief cognitive behavioral therapy for suicide prevention (BCBT) has demonstrated preliminary efficacy as a psychotherapeutic intervention that reduces suicide attempts among U.S. Army Soldiers. The generalizability of BCBT's effects in other military groups and its underlying mechanisms of action remain unknown, however. The Marine Suicide Prevention and Intervention REsearch (M-SPIRE) study is designed to test the efficacy of BCBT for the prevention of suicide attempts among active duty U.S. Marines with recent suicidal ideation or attempts and to identify potential mechanisms of change contributing to BCBT's effects. In this protocol paper, we describe M-SPIRE's rationale and methods with a particular emphasis on measuring treatment fidelity and BCBT's hypothesized mechanisms of action.

Associations among state-level physical distancing measures and suicidal thoughts and behaviors among U.S. adults during the early COVID-19 pandemic

PURPOSE

The purpose of this study was to identify leading sources of stress, describe rates of mental health outcomes, and examine their associations among U.S. adults during the first months of the COVID-19 pandemic.

METHOD

In a cross-sectional, general population survey conducted from March 18 to April 4, 2020, U.S. adults (n = 10,625) were recruited through Qualtrics Panels using quota sampling methods.

RESULTS

Life stressors, probable depression, past-month suicide ideation, and past-month suicide attempts were not elevated among participants subject to state-level stay-at-home orders and/or large gathering bans. Multiple life stressors were associated with increased rates of probable depression. Past-month suicide ideation was significantly higher among participants reporting ongoing arguments with a partner and serious legal problems. Past-month suicide attempt was significantly higher among participants reporting concerns about a life-threatening illness or injury, but was significantly lower among participants reporting an unexpected bill or expense.

CONCLUSIONS

Results failed to support the conclusion that physical distancing measures are correlated with worse mental health outcomes. Concerns about life-threatening illness or injury were uniquely associated with increased risk of suicide attempt.

Percutaneous CT-Guided Core Needle Biopsies of Head and Neck Masses: Technique, Histopathologic Yield, and Safety at a Single Academic Institution

BACKGROUND AND PURPOSE

CT-guided head and neck biopsies can be challenging due to the anatomy and adjacent critical structures but can often obviate the need for open biopsy. A few studies and review articles have described approaches to biopsy in the head and neck. This retrospective study evaluated technical considerations, histopathologic yield, and safety in CT-guided head and neck core needle biopsies.

MATERIALS AND METHODS

A retrospective review of head and neck biopsies performed from January 2013 through December 2019 was conducted. Clinical diagnosis and indication, patient demographics, mass location and size, biopsy needle type, technical approach, dose-length product, sedation details, complications, diagnostic histopathologic yield, and the use of iodinated contrast were recorded for each case.

RESULTS

A total of 27 CT-guided head and neck core needle biopsies were performed in 26 patients. The diagnostic sample rate was 100% (27/27). A concordant histopathologic diagnosis was obtained in 93% (25/27) of cases. There was a single complication of core needle biopsy, a small asymptomatic superficial hematoma.

CONCLUSIONS

Percutaneous CT-guided biopsy of deep masses in the head and neck is safe and effective with careful biopsy planning and has a high diagnostic yield that can obviate the need for open biopsy.

The PRImary care Screening Methods (PRISM) study: Rationale and design considerations

BACKGROUND

Primary care is the most frequently visited clinic type immediately prior to suicidal behavior, with nearly half of suicide decedents visiting a primary care provider within a month of their death. Data supporting the efficacy of suicide risk screening in this setting is lacking, however. Improved suicide risk screening in primary care could lead to earlier intervention and treatment.

PURPOSE

The PRImary care Screening Methods (PRISM) study is designed to develop and evaluate the efficacy of an alert algorithm that can be used by military primary care providers to accurately identify high-risk patients, to improve the identification of high-risk patients who deny suicidal thoughts, and to quantify patient subgroups who are more likely to be missed by existing screening methods (i.e., false negatives).

METHODS

The rationale of the PRISM study is discussed, along with ethical and design considerations related to the conduct of suicide prevention research. The PRISM study enrolled 2690 patients from six primary care clinics across the U.S. Patients were enrolled during routine visits to a primary care clinic, and completed a battery of self-report scales in clinic waiting rooms. Follow-up phone interviews are conducted 1, 6, and 12 months after enrollment. The primary outcome is suicide attempt.

CONCLUSIONS

PRISM is the first study to prospectively examine multiple suicide risk screening methods in "real-world" military primary care clinics. Ethical and design issues were considered to ensure that human participants, especially suicidal patients, were adequately protected while minimizing the potential confounding effect of risk management protocols.

Effect of Augmenting Standard Care for Military Personnel With Brief Caring Text Messages for Suicide Prevention: A Randomized Clinical Trial

IMPORTANCE

Accessible and cost-effective interventions for suicidality are needed to address high rates of suicidal behavior among military service members. Caring Contacts are brief periodic messages that express unconditional care and concern and have been previously shown to prevent suicide deaths, attempts, ideation, and hospitalizations.

OBJECTIVE

To test the effectiveness of augmenting standard military health care with Caring Contacts delivered via text message to reduce suicidal thoughts and behaviors over 12 months.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was conducted at 3 military installations in the southern and western United States. Soldiers and Marines identified as being at risk of suicide were recruited between April 2013 and September 2016. The final follow-up was in September 2017.

INTERVENTIONS

Both groups received standard care, and the Caring Contacts group also received consisted of 11 text messages delivered on day 1, at week 1, at months 1, 2, 3, 4, 6, 8, 10, and 12, and on participants' birthdays.

MAIN OUTCOMES AND MEASURES

Primary outcomes were current suicidal ideation and suicide risk incidents (hospitalization or medical evacuation). Secondary outcomes were worst-point suicidal ideation, emergency department visits, and suicide attempts. Suicidal ideation was measured by the Scale for Suicide Ideation, suicide risk incidents, and emergency department visits by the Treatment History Interview; attempted suicide was measured by the Suicide Attempt Self-Injury Count.

RESULTS

Among 658 randomized participants (329 randomizely assigned to each group), data were analyzed for 657 individuals (mean [SD] age, 25.2 [6.1] years; 539 men [82.0%]). All participants reported suicidal ideation at baseline, and 291 (44.3%) had previously attempted suicide. Of the 657 participants, 461 (70.2%) were assessed at 12 months. Primary outcomes were nonsignificant. There was no significant effect on likelihood or severity of current suicidal ideation or likelihood of a suicide risk incident; there was also no effect on emergency department visits. However, participants who received Caring Contacts (172 of 216 participants [79.6%]) had lower odds than those receiving standard care alone (179 of 204 participants [87.7%]) of experiencing any suicidal ideation between baseline and follow-up (odds ratio, 0.56 [95% CI, 0.33-0.95]; P = .03) and fewer had attempted suicide since baseline (21 of 233 [9.0%] in the group receiving Caring Contacts vs 34 of 228 [14.9%] in the standard-care group; odds ratio, 0.52 [95% CI, 0.29-0.92]; P = .03).

CONCLUSIONS AND RELEVANCE

This trial provides inconsistent results on the effectiveness of caring text messages between primary and secondary outcomes, but this inexpensive and scalable intervention offers promise for preventing suicide attempts and ideation in military personnel. Additional research is needed.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01829620.

Global hormone profiling of murine placenta reveals Secretin expression

OBJECTIVE

To elucidate and categorize the murine placental hormones expressed across gestation, including the expression of hormones with previously undescribed roles.

STUDY DESIGN

Expression levels of all genes with known or predicted hormone activity expressed in two separate tissues, the placenta and maternal decidua, were assessed across a timecourse spanning the full lifetime of the placenta. Novel expression patterns were confirmed by in situ hybridization and protein level measurements.

RESULTS

A combination of temporal and spatial information defines five groups that can accurately predict the patterns of uncharacterized hormones. Our analysis identified Secretin, a novel placental hormone that is expressed specifically by the trophoblast at levels many times greater than in any other tissue.

CONCLUSIONS

The characteristics of Secretin fit the paradigm of known placental hormones and suggest that it may play an important role during pregnancy.

Transgenic production of cytokinin suppresses bacterially induced hypersensitive response symptoms and increases antioxidative enzyme levels in Nicotiana spp

Responses of cytokinin overproducing transgenic Nicotiana plants to infections with compatible and incompatible Pseudomonas syringae pathovars were compared. Plants used were transformed with the ipt(isopentenyl transferase) gene that catalyzes the synthesis of cytokinin. In cytokinin overproducing lines that carry the ipt gene fused to the CaMV 35S (Nt+ipt), the wound-inducible proteinase inhibitor II (Ntx+ipt), or the light-inducible Rubisco small subunit protein (Npl+ipt) promoter, development of the hypersensitive response (HR) after infection with incompatible bacteria (P. syringae pv. tomato) was significantly inhibited as compared to the untransformed (Nt) controls. Over a 12 h period following inoculation, P. syrinage pv. tomato populations were slightly reduced in leaves of the cytokinin-overproducing Nt-ipt line compared with the Nt control. When the compatible P. syringae. pv. tabaci was used to infect the ipt transformed lines, slight or no significant differences in necrosis development were observed. Following infection, the titer of P. syringae pv. tabaci increased rapidly in both the transgenic and control lines but was higher in Nt+ipt plants. Leaf superoxide dismutase and catalase enzyme activities were about 60% higher in ipt leaf extracts than in the controls. This augmented antioxidant capacity likely decreased the amount of H(2)O(2) that may be associated with the higher tolerance of plants to pathogen-induced necrosis. In addition, the Nt+ipt lines had a significantly lower molar ratio of free sterols to phospholipids. The more stable membrane lipid composition and the higher antioxidant capacity likely contributed to the suppressed HR symptoms in the cytokinin overproducing Nt+ipt plants. In conclusion, the overproduction of cytokinins in tobacco appears to suppress the HR symptoms induced by incompatible bacteria.

Genome-wide expression profiling of placentas in the p57Kip2 model of pre-eclampsia

Pre-eclampsia affects 6-10% of pregnancies and is one of the primary causes of premature birth. It is widely accepted that inappropriate placental development, combined with environmental factors, plays a major role in disease pathogenesis. The p57(Kip2) mouse is the only mouse model of pre-eclampsia that recapitulates the full spectrum of symptoms of the human disease, including placental abnormalities, hypertension, proteinuria and premature labour. In addition, pregnant females expressing wild-type levels of p57(Kip2) develop pre-eclampsia when carrying fetuses that lack p57(Kip2) expression. This demonstrates that either the fetus or the placenta causes the disease. Here, taking advantage of the unique genetics of the p57(Kip2) mouse, we have used full genome expression profiling to define the placental aspect of the p57(Kip2) phenotype at a molecular level and to conduct an unbiased search for factors involved in pre-eclampsia pathogenesis. During this analysis, we found that although mutant embryos demonstrate altered placental architecture and have histological changes indicative of reduced utero-placental blood flow, the p57(Kip2) pregnant females do not demonstrate hypertension or renal pathology. This suggests a model in which placental abnormalities cause pre-eclampsia only given other environmental variables. On the basis of this model, we expect that misregulation of molecular factors, while not able to cause a full spectrum of disease symptoms in this context, still occurs in these p57(Kip2) mutant mice. Our studies suggest a role for environmental factors in the p57(Kip2) pre-eclampsia phenotype and have identified several candidates for pre-eclampsia predisposition in this model, including known regulators of blood pressure, inflammation and apoptosis.

Experimental Inoculation of Pregnant Swine with Type 1 Bovine Viral Diarrhoea Virus

The ability of bovine viral diarrhoea virus type 1 (BVDV-1) to induce transplacental infection in pigs was evaluated. Control pigs (n = 4) were sham-inoculated while infected pigs (n = 4) were intranasally inoculated with BVDV-1 on day 65 of gestation. Blood samples were tested throughout the study for BVDV and antibody to BVDV. On day 110 of gestation, a Caesarean section was performed. Serum was obtained for virus isolation and antibody determination from all piglets, and all experimental animals were killed. Tissues were collected for virus isolation and histopathology. Bovine viral diarrhoea virus was isolated on days 5 and 7 after infection and seroconversion was demonstrated in all infected gilts; however, BVDV was only isolated from one fetus from an infected pig. Viraemia and seroconversion were demonstrated in the pregnant gilts; however, transplacental infection at day 65 of gestation in the pig was not consistently demonstrated.

Distinct regulatory properties of pyruvate dehydrogenase kinase and phosphatase isoforms

The mammalian pyruvate dehydrogenase complex (PDC) plays central and strategic roles in the control of the use of glucose-linked substrates as sources of oxidative energy or as precursors in the biosynthesis of fatty acids. The activity of this mitochondrial complex is regulated by the continuous operation of competing pyruvate dehydrogenase kinase (PDK) and pyruvate dehydrogenase phosphatase (PDP) reactions. The resulting interconversion cycle determines the fraction of active (nonphosphorylated) pyruvate dehydrogenase (E1) component. Tissue-specific and metabolic state-specific control is achieved by the selective expression and distinct regulatory properties of at least four PDK isozymes and two PDP isozymes. The PDK isoforms are members of a family of serine kinases that are not structurally related to cytoplasmic Ser/Thr/Tyr kinases. The catalytic subunits of the PDP isoforms are Mg2+-dependent members of the phosphatase 2C family that has binuclear metal-binding sites within the active site. The dihydrolipoyl acetyltransferase (E2) and the dihydrolipoyl dehydrogenase-binding protein (E3BP) are multidomain proteins that form the oligomeric core of the complex. One or more of their three lipoyl domains (two in E2) selectively bind each PDK and PDP1. These adaptive interactions predominantly influence the catalytic efficiencies and effector control of these regulatory enzymes. When fatty acids are the preferred source of acetyl-CoA and NADH, feedback inactivation of PDC is accomplished by the activity of certain kinase isoforms being stimulated upon preferentially binding a lipoyl domain containing a reductively acetylated lipoyl group. PDC activity is increased in Ca2+-sensitive tissues by elevating PDP1 activity via the Ca2+-dependent binding of PDP1 to a lipoyl domain of E2. During starvation, the irrecoverable loss of glucose carbons is restricted by minimizing PDC activity due to high kinase activity that results from the overexpression of specific kinase isoforms. Overexpression of the same PDK isoforms deleteriously hinders glucose consumption in unregulated diabetes.

Platelet aggregation responses and virus isolation from platelets in calves experimentally infected with type I or type II bovine viral diarrhea virus

Altered platelet function has been reported in calves experimentally infected with type II bovine viral diarrhea virus (BVDV). The purpose of the present study was to further evaluate the ability of BVDV isolates to alter platelet function and to examine for the presence of a virus-platelet interaction during BVDV infection. Colostrum-deprived Holstein calves were obtained immediately after birth, housed in isolation, and assigned to 1 of 4 groups (1 control and 3 treatment groups). Control calves (n = 4) were sham inoculated, while calves in the infected groups (n = 4 for each group) were inoculated by intranasal instillation with 10(7) TCID50 of either BVDV 890 (type II), BVDV 7937 (type II), or BVDV TGAN (type I). Whole blood was collected prior to inoculation (day 0) and on days 4, 6, 8, 10, and 12 after inoculation for platelet function testing by optical aggregometry by using adenosine diphosphate and platelet activating factor. The maximum percentage aggregation and the slope of the aggregation curve decreased over time in BVDV-infected calves; however, statistically significant differences (Freidman repeated measures ANOVA on ranks, P < 0.05) were only observed in calves infected with the type II BVDV isolates. Bovine viral diarrhea virus was not isolated from control calves, but was isolated from all calves infected with both type II BVDV isolates from days 4 through 12 after inoculation. In calves infected with type I BVDV, virus was isolated from 1 of 4 calves on days 4 and 12 after inoculation and from all calves on days 6 and 8 after inoculation. Altered platelet function was observed in calves infected with both type II BVDV isolates, but was not observed in calves infected with type I BVDV. Altered platelet function may be important as a difference in virulence between type I and type II BVDV infection.

Study of cattle persistently infected with bovine viral diarrhea virus that lack detectable virus in serum

OBJECTIVE

To determine whether cattle persistently infected with bovine viral diarrhea virus (BVDV) that lack virus detectable in serum by use of the immunoperoxidase microtiter assay (IPMA) can transmit the virus to susceptible herdmates and determine prevalence of these cattle.

DESIGN

Clinical trial and serologic survey.

SAMPLE POPULATION

2 cattle and 1,952 blood samples.

PROCEDURE

A persistently infected cow in which virus could not be detected in serum was housed with a BVDV-seronegative steer. Blood and nasal swab specimens were tested via virus isolation and serum virus neutralization. Parallel WBC preparations and sera from blood samples of 1,952 adult cows were screened for BVDV by use of IPMA.

RESULTS

The steer seroconverted to BVDV within 4 weeks of contact with the cow. Virus was detected in sera and WBC of 5 adult cows that were verified as persistently infected by retest 3 weeks later. Cattle persistently infected with BVDV in which virus could not be detected in both serum and WBC by use of IPMA were not found.

CONCLUSION AND CLINICAL RELEVANCE

Cattle persistently infected with BVDV in which virus cannot be detected in serum by use of IPMA may serve as virus reservoirs for infecting susceptible cattle. Persistent infection was detected at a prevalence of 0.26%. Screening adult cattle by use of IPMA on serum samples appears to be a reliable means of detecting persistent infection with BVDV. Prevalence of cattle persistently infected with BVDV that have negative results of IPMA on serum is extremely low.

Relationship between degree of viremia and disease manifestation in calves with experimentally induced bovine viral diarrhea virus infection

OBJECTIVE

To compare degree of viremia and disease manifestations in calves with type-I and -II bovine viral diarrhea virus (BVDV) infection.

ANIMALS

16 calves.

PROCEDURE

Colostrum-deprived calves obtained immediately after birth were assigned to 1 control and 3 treatment groups (4 calves/group). Calves in treatment groups were inoculated (day 0) by intranasal instillation of 10(7) median tissue culture infective dose BVDV 890 (type II), BVDV 7937 (type II), or BVDV TGAN (type I). Blood cell counts and virus isolation from serum and leukocytes were performed daily, whereas degree of viremia was determined immediately before and 4, 6, 8, and 12 days after inoculation. Calves were euthanatized on day 12, and pathologic, virologic, and immunohistochemical examinations were performed.

RESULTS

Type-II BVDV 890 induced the highest degree of viremia, and type-I BVDV TGAN induced the lowest. Virus was isolated more frequently and for a longer duration in calves inoculated with BVDV 890. A parallel relationship between degree of viremia and rectal temperature and an inverse relationship between degree of viremia and blood cell counts was observed. Pathologic and immunohistochemical examinations revealed more pronounced lesions and more extensive distribution of viral antigen in calves inoculated with type-II BVDV.

CONCLUSIONS AND CLINICAL RELEVANCE

Degree of viremia induced during BVDV infection is associated with severity of clinical disease. Isolates of BVDV that induce a high degree of viremia may be more capable of inducing clinical signs of disease. Strategies (eg, vaccination) that reduce viremia may control clinical signs of acute infection with BVDV.

Reaction Mechanism for Mammalian Pyruvate Dehydrogenase Using Natural Lipoyl Domain Substrates

The pyruvate dehydrogenase (E1) component of the pyruvate dehydrogenase complex (PDC) catalyzes a two-step reaction. Recombinant production of substrate amounts of the lipoyl domains of the dihydrolipoyl transacetylase (E2) component of the mammalian PDC allowed kinetic characterization of the rapid physiological reaction catalyzed by E1. Using either the N-terminal (L1) or the internal (L2) lipoyl domain of E2 as a substrate, analyses of steady state kinetic data support a ping pong mechanism. Using standard E1 preparations, Michaelis constants (Km) were 52 +/- 14 microM for L1 and 24.8 +/- 3.8 microM for pyruvate and k(cat) was 26.3 s(-1). With less common, higher activity preparations of E1, the Km values were > or =160 microM for L1 and > or =35 microM for pyruvate and k(cat) was > or =70 s(-1). Similar results were found with the L2 domain. The best synthetic lipoylated-peptide (L2 residues 163-177) was a much poorer substrate (Km > or =15 mM, k(cat) approximately equals 5 s(-1); k(cat)/Km decreased >1,500-fold) than L1 or L2, but a far better substrate in the E1 reaction than free lipoamide (k(cat)/Km increased >500-fold). Each lipoate source was an effective substrate in the dihydrolipoyl dehydrogenase (E3) reaction, but E3 had a lower Km for the L2 domain than for lipoamide or the lipoylated peptides. In contrast to measurements with slow E1 model reactions that use artificial acceptors, we confirmed that the natural E1 reaction, using lipoyl domain acceptors, was completely inhibited (>99%) by phosphorylation of E1 and the phosphorylation strongly inhibited the reverse of the second step catalyzed by E1. The mechanisms by which phosphorylation interferes with E1 activity is interpreted based on accrued results and the location of phosphorylation sites mapped onto the 3-D structure of related alpha-keto acid dehydrogenases.

Caprine mucopolysaccharidosis IIID: a preliminary trial of enzyme replacement therapy

Mucopolysaccharidosis type IIID (MPS IIID) is a lysosomal storage disorder resulting from lack of activity of the lysosomal hydrolase N-acetylglucosamine 6-sulfatase (6S) (EC 3.1.6.14). The syndrome is associated with systemic and central nervous system (CNS) heparan sulfate glycosaminoglycan (HS-GAG) accumulation, secondary storage of lipids, and severe, progressive dementia. In this investigation, caprine MPS IIID, established as a large animal model for the human disease, was used to evaluate the efficacy of enzyme replacement therapy (ERT). Recombinant caprine 6S (rc6S) (1 mg/kg/dose) was administered intravenously to one MPS IIID goat kid at 2, 3, and 4 wks of age. Five days after the last dose, the uronic acid (UA) content and the composition of uncatabolized HS-GAG fractions in the brain of the ERT-treated MPS IIID kid were similar to those from a control, untreated MPS IIID animal. However, hepatic uronic acid levels in the treated MPS IIID kid were approximately 90% lower than those in the untreated MPS IIID control; whereas the composition of the residual hepatic HS-GAG was identical to that in the untreated animal. Marked reduction of lysosomal storage vacuoles in hepatic cells of the treated MPS IIID kid was observed, but ERT had no effect on CNS lesions. No residual 6S activity was detected in brain or liver. This preliminary investigation indicates that other treatment regimens will be necessary to ameliorate MPS III-related CNS lesions.

Development of a standardized methodology for double-blind, placebo-controlled food challenge in patients with brittle asthma and perceived food intolerance

OBJECTIVE

To develop a standardized, double-blind, placebo-controlled, food challenge (DBPCFC) methodology for identifying food intolerance in patients with brittle asthma.

SUBJECTS/SETTING

Patients with brittle asthma and perceived food intolerance were studied in hospital.

DESIGN

Each of 3 protocols began with 5 days of dietary exclusion. Protocol 1 consisted of open food challenges in 29 patients, protocol 2 consisted of 2 daily DBPCFCs in 22 patients, and protocol 3 involved 1 daily DBPCFC in 18 patients. Total immunoglobulin E level was measured and food-specific radioallergosorbent tests and skin prick tests were conducted. A standard panel of hyperallergenic foods were masked in a soup (developed specially for this study) for every food challenge. Peak expiratory flow, forced expiratory volume, and symptoms were assessed as objective measures of response. Open food challenges at home followed each protocol. Each protocol took approximately 14 days in the hospital and 4 to 6 months at home.

RESULTS

For protocols 1, 2 and 3, positive reactions were experienced by 52%, 55%, and 66% of patients, respectively. Radioallergosorbent tests and skin prick tests were shown to have 40% and 71% sensitivity, respectively, and 74% and 77% specificity for predicting a positive food challenge.

APPLICATIONS/CONCLUSIONS

The high prevalence of food intolerance in patients with brittle asthma was confirmed, as was the poor positive predictive value of skin prick tests and radioallergosorbent tests. The food challenge method developed enables standardized identification of food intolerances in patients with brittle asthma and may be useful in other groups.

Serotyping of Mannheimia (Pasteurella) haemolytica isolates from the upper Midwest United States

Mannheimia (Pasteurella) haemolytica biotype A serotype1 (A1) is the primary bacterial agent responsible for the clinical signs and pathophysiologic events in bovine pneumonic pasteurellosis. The goal of this study was to determine the prevalence of other serotypes of M. haemolytica biotype A organisms obtained from the upper Midwest diagnostic laboratories. A total of 147 M. haemolytica isolates were collected from Minnesota, South Dakota, and Michigan. Isolates were tested against M. haemolytica antisera obtained from the National Animal Disease Center, Ames, Iowa. Results indicated that M. haemolytica serotype 1 represented approximately 60%, serotype 6 represented 26%, and serotype 2 represented 7% of the total examined isolates. In addition, 7% of the isolates were serotype 9, 11, or untypable. This finding suggests that M. haemolytica serotypes other than serotype 1 can be isolated from the lung lesions of diseased cattle and seem to be capable of causing the pathologic changes observed in the lung with pneumonic pasteurellosis.

Diet and asthma

The role of food intolerance in asthma is well recognized, and where food avoidance measures are instituted considerable improvement in asthma symptoms and in reduction in drug therapy and hospital admissions can result. These benefits may have a greater impact in those patients with greater symptoms. However, the promise of such benefits should not result in an approach which ignores inhaled drug therapy, or in a dietary regime which is inappropriate in the face of mild symptoms. Whilst sub-optimal intake of dietary nutrients is also a recently recognized potential risk factor for asthma, available data are insufficient to implicate any as casual. A number of studies have sought to establish the role of the antioxidant vitamins, A, C and E and selenium, yet others of the elements sodium and magnesium. Sub-optimal nutrient intake may enhance asthmatic inflammation, consequently contributing to bronchial hyperreactivity. Prospective studies of supplementation therapy are needed to confirm this.

Marked differences between two isoforms of human pyruvate dehydrogenase kinase

Pyruvate dehydrogenase kinase (PDK) isoforms 2 and 3 were produced via co-expression with the chaperonins GroEL and GroES and purified with high specific activities in affinity tag-free forms. By using human components, we have evaluated how binding to the lipoyl domains of the dihydrolipoyl acetyltransferase (E2) produces the predominant changes in the rates of phosphorylation of the pyruvate dehydrogenase (E1) component by PDK2 and PDK3. E2 assembles as a 60-mer via its C-terminal domain and has mobile connections to an E1-binding domain and then two lipoyl domains, L2 and L1 at the N terminus. PDK3 was activated 17-fold by E2; the majority of this activation was facilitated by the free L2 domain (half-maximal activation at 3.3 microm L2). The direct activation of PDK3 by the L2 domain resulted in a 12.8-fold increase in k(cat) along with about a 2-fold decrease in the K(m) of PDK3 for E1. PDK3 was poorly inhibited by pyruvate or dichloroacetate (DCA). PDK3 activity was stimulated upon reductive acetylation of L1 and L2 when full activation of PDK3 by E2 was avoided (e.g. using free lipoyl domains or ADP-inhibited E2-activated PDK3). In marked contrast, PDK2 was not responsive to free lipoyl domains, but the E2-60-mer enhanced PDK2 activity by 10-fold. E2 activation of PDK2 resulted in a greatly enhanced sensitivity to inhibition by pyruvate or DCA; pyruvate was effective at significantly lower levels than DCA. E2-activated PDK2 activity was stimulated >/=3-fold by reductive acetylation of E2; stimulated PDK2 retained high sensitivity to inhibition by ADP and DCA. Thus, PDK3 is directly activated by the L2 domain, and fully activated PDK3 is relatively insensitive to feed-forward (pyruvate) and feed-back (acetylating) effectors. PDK2 was activated only by assembled E2, and this activated state beget high responsiveness to those effectors.

Regression of poloxamer 407-induced atherosclerotic lesions in C57BL/6 mice using atorvastatin

HMG-CoA reductase inhibitor drugs or 'statins' have been shown to effectively reduce plasma total cholesterol (CHOL), CHOL associated with low-density-lipoprotein (LDL), and triglycerides (TG). In addition, slight elevations in HDL-CHOL are also typically observed. Poloxamer 407 (P-407), a nonionic surfactant, effectively elevates both plasma CHOL and especially TG in a dose-controlled fashion and results in formation of atherosclerotic lesions in the aortas of C57BL/6 mice without the requirement of dietary cholic acid [1,2]. The purpose of the present study was to assess whether a typical statin, namely atorvastatin (Lipitor(R)) would significantly reduce P-407-induced hypercholesterolemia and hypertriglyceridemia as well as cause regression of atherosclerotic lesions resulting from administration of P-407 to C57BL/6 mice. C57BL/6 mice in the present study were treated with either normal saline (C, controls), 0.5 g/kg of P-407 (P), or a high-fat, high-cholesterol, cholate-containing diet (HF) for 120 days. Mice in all groups were then equally and randomly divided and treated with either atorvastatin or saline for an additional 120 days. Beginning at Day 121 and using mice in groups P and HF as an example, one-fourth of the mice in each group received 20 mg/kg per day of atorvastatin with either concomitant HF feeding or P-407 administration ('progression' treatment groups), one-fourth received 20 mg/kg per day of atorvastatin following cessation of HF feeding or P-407 administration, one-fourth received saline (placebo) with either simultaneous HF feeding or P-407 administration ('progression' placebo groups), and one-fourth received saline (placebo) following cessation of HF feeding or P-407 administration. Total plasma CHOL was significantly (P<0.01) lower for mice in groups P and HF when administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to total plasma CHOL of C mice. With discontinuation of either P-407 administration or HF feeding, total plasma CHOL declined rapidly in both P and HF mice with atorvastatin-treated mice generally demonstrating lower plasma CHOL concentrations relative to saline-treated mice. Total plasma TG was significantly (P<0.01) lower for mice in group P administered atorvastatin relative to saline, but remained significantly (P<0.05) elevated compared to plasma TG of C mice. With discontinuation of P-407 administration, total plasma TG declined rapidly in P mice with atorvastatin-treated mice typically demonstrating lower plasma TG concentrations relative to saline-treated P mice. Aortas of mice treated with 20 mg/kg per day of atorvastatin in both groups P and HF, whether maintained on the HF-diet or treated with P-407 from Day 120 to 240 or whether each treatment was terminated at Day 120, revealed no presence of atherosclerotic lesions relative to saline-treated mice and were indistinguishable from aortas retrieved from C mice. Atorvastatin at a dose of 20 mg/kg per day not only significantly reduced the plasma CHOL and TG concentrations, but also resulted in regression of atherosclerotic lesions induced in C57BL/6 mice by administration of P-407 or ingestion of a HF-diet containing cholic acid.

Potential downregulation of HMG-CoA reductase after prolonged administration of P-407 in C57BL/6 mice

This study investigated the potential alteration in the amount of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase messenger RNA (mRNA) and lipoprotein lipase (LPL) mRNA in the livers of C57BL/6 mice after long-term (200 days) treatment with the nonionic surfactant called poloxamer 407 (P-407). Previously, P-407 has been used to produce a dose-controlled hyperlipidemic state in C57BL/6 mice with subsequent formation of atherosclerotic lesions. Five groups of mice were studied; controls (C); mice fed a standard chow diet enriched with only cholic acid (CH); mice fed the high-cholesterol, high-fat Paigen diet (HF); mice treated with 0.5 g/kg P-407 every third day (P); and mice administered 0.5 g/kg P-407 every third day while consuming a diet identical to that of mice in group CH (PC). Neither a significant (p < 0.05) weight loss nor alteration in liver enzymes (AST and ALT) were observed for any group throughout the study when compared with the control mice. Total plasma cholesterol (CHOL) was significantly elevated compared with controls for mice in groups HF, P, and PC, whereas total plasma triglycerides (TG) were significantly increased for mice in only groups P and PC. Long-term ingestion of a high-fat diet or a diet enriched in cholic acid resulted in a significant (p < 0.05) reduction in HDL-CHOL when compared with controls. Plasma samples assayed at 200 days for mice in groups HF and P showed a shift in the lipoprotein fraction distribution primarily to VLDL-CHOL as compared with mice in group C in which, as expected, most of the CHOL was contained in the HDL fraction. The biologic activity of HMG-CoA reductase assayed in hepatic microsomal homogenates was significantly reduced for mice in groups CH (p < 0.01), HF (p < 0.01), and PC (p < 0.05), but not for mice in group P, when compared with control. A statistical analysis of the data demonstrated significant (p < 0.05) reductions in the HMG-CoA reductase mRNA levels in hepatic tissue for all treatment groups relative to mRNA levels determined for mice in group C. In contrast, no treatment group demonstrated a significant difference in hepatic LPL mRNA levels when compared with mRNA levels determined for control animals. These data demonstrate that P-407 administration to C57BL/6 mice significantly decreased the amount of HMG-CoA reductase mRNA detected in liver.

Wnt signaling in Xenopus embryos inhibits bmp4 expression and activates neural development

We report a new role for Wnt signaling in the vertebrate embryo: the induction of neural tissue from ectoderm. Early expression of mouse wnt8, Xwnt8, beta-catenin, or dominant-negative GSK3 induces the expression of neural-specific markers and inhibits the expression of Bmp4 in Xenopus ectoderm. We show that Wnt8, but not the BMP antagonist Noggin, can inhibit Bmp4 expression at early gastrula stages. Furthermore, inhibition of beta-catenin activity in the neural ectoderm of whole embryos by a truncated TCF results in a decrease in neural development. Therefore, we suggest that a cleavage-stage Wnt signal normally contributes to an early repression of Bmp4 on the dorsal side of the embryo and sensitizes the ectoderm to respond to neural inducing signals from the organizer. The Wnt targets Xnr3 and siamois have been shown previously to have neuralizing activity when overexpressed. However, antagonists of Wnt signaling, dnXwnt8 and Nxfrz8, inhibit Wnt-mediated Xnr3 and siamois induction, but not neural induction, suggesting an alternative mechanism for Bmp repression and neuralization. Conversely, dnTCF blocks both Wnt-mediated Xnr3 and neural induction, suggesting that both pathways require this transcription factor.

Experimental model of type II bovine viral diarrhea virus-induced thrombocytopenia in neonatal calves

Thrombocytopenia has been associated with type II bovine viral diarrhea virus (BVDV) infection in immunocompetent cattle, but the mechanism is unknown. The purpose of the present study was to develop and characterize a model of type II BVDV-induced thrombocytopenia. Colostrum-deprived Holstein calves were obtained immediately after birth, given a BVDV-negative and BVDV antibody-negative plasma transfusion, housed in an isolation facility, and randomly assigned to either control (n = 4) or infected (n = 5) groups. Infected calves were inoculated by intranasal instillation on day 3 of age with 10(7) TCID50 of the prototype type II isolate, BVDV 890, whereas control calves were sham inoculated. Blood counts and virus isolations from serum, white blood cells, and platelets were performed daily until day 12 after infection, at which time all experimental calves were euthanatized, and pathologic, virologic, and immunohistochemical examinations were performed. On physical examination, the control calves remained normal, but the infected calves developed pyrexia and diarrhea characteristic of type II BVDV infection. The platelet count decreased in all infected calves, and a statistically significant difference in the platelet count between control and infected calves was observed on days 7-12 after infection. In addition, the mean platelet volume and white blood cell counts also decreased. Examination of the bone marrow from the infected calves revealed immunohistochemical staining for BVDV antigen in megakaryocytes and evidence of concurrent megakaryocyte necrosis and hyperplasia.