Implementation of clopidogrel pharmacogenetic clinical decision support for a preemptive return of results program

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

To describe our experiences implementing and iterating CYP2C19 genotype-guided clopidogrel pharmacogenetic clinical decision support (CDS) tools over time in the setting of a large health system-wide, preemptive pharmacogenomics program.

SUMMARY

Clopidogrel-treated patients who are genetically predicted cytochrome P450 isozyme 2C19 intermediate or poor metabolizers have an increased risk of atherothrombotic events, some of which can be life-threatening. The Clinical Pharmacogenetics Implementation Consortium provides guidance for the use of clopidogrel based on CYP2C19 genotype in patients with cardiovascular and cerebrovascular diseases. Our multidisciplinary team implemented an automated, interruptive alert that fires when clopidogrel is ordered or refilled for biobank participants with structured CYP2C19 intermediate or poor metabolizer genomic indicators in the electronic health record. The implementation began with a narrow cardiovascular indication and setting and was then scaled in 4 primary dimensions: (1) clinical indication; (2) availability across health-system locations; (3) care venue (e.g., inpatient vs outpatient); and (4) provider groups (eg, cardiology and neurology). We iterated our approach over time based on evolving clinical evidence and proactive strategies to optimize CDS maintenance and sustainability. A key facilitator of expansion was socialization of the broader pharmacogenomics initiative among our academic medical center community, accompanied by clinician acceptance of pharmacogenetic alerts in practice.

CONCLUSION

A multidisciplinary collaboration is recommended to facilitate the use of CYP2C19 genotype-guided antiplatelet therapy in patients with cardiovascular and cerebrovascular diseases. Evolving clopidogrel pharmacogenetic evidence necessitates thoughtful iteration of implementation efforts and strategies to optimize long-term maintenance and sustainability.

Patient-Level Exposure to Actionable Pharmacogenomic Medications in a Nationally Representative Insurance Claims Database

BACKGROUND

The prevalence of exposure to pharmacogenomic medications is well established but little is known about how long patients are exposed to these medications.

AIM

Our objective was to describe the amount of exposure to actionable pharmacogenomic medications using patient-level measures among a large nationally representative population using an insurance claims database.

METHODS

Our retrospective cohort study included adults (18+ years) from the IQVIA PharMetrics® Plus for Academics claims database with incident fills of 72 Clinical Pharmacogenetics Implementation Consortium level A, A/B, or B medications from January 2012 through September 2018. Patient-level outcomes included the proportion of days covered (PDC), number of fills, and average days supplied per fill over a 12-month period.

RESULTS

Over 1 million fills of pharmacogenetic medications were identified for 605,355 unique patients. The mean PDC for all medications was 0.21 (SD 0.3), suggesting patients were exposed 21% (77 days) of the year. Medications with the highest PDC (0.55-0.89) included ivacaftor, tamoxifen, clopidogrel, HIV medications, transplant medications, and statins; with the exception of statins, these medications were initiated by fewer patients. Pharmacogenomic medications were filled an average of 2.8 times (SD 3.0, range 1-81) during the year following the medication's initiation, and the average days supplied for each fill was 22.3 days (SD 22.4, range 1-180 days).

CONCLUSION

Patient characteristics associated with more medication exposure were male sex, older age, and comorbid chronic conditions. Prescription fill data provide patient-level exposure metrics that can further our understanding of pharmacogenomic medication utilization and help inform opportunities for pharmacogenomic testing.

Chikungunya Virus Vaccine Candidate Incorporating Synergistic Mutations Is Attenuated and Protects Against Virulent Virus Challenge

BACKGROUND

Chikungunya virus (CHIKV) is an arbovirus that periodically emerges to cause large epidemics of arthritic disease. Although the robust immunity elicited by live-attenuated virus (LAV) vaccine candidates makes them attractive, CHIKV vaccine development has been hampered by a high threshold for acceptable adverse events.

METHODS

We evaluated the vaccine potential of a recently described LAV, skeletal muscle-restricted virus (SKE), that exhibits diminished replication in skeletal muscle due to insertion of target sequences for skeletal muscle-specific miR-206. We also evaluated whether these target sequences could augment safety of an LAV encoding a known attenuating mutation, E2 G82R. Attenuation of viruses containing these mutations was compared with a double mutant, SKE G82R.

RESULTS

SKE was attenuated in both immunodeficient and immunocompetent mice and induced a robust neutralizing antibody response, indicating its vaccine potential. However, only SKE G82R elicited diminished swelling in immunocompetent mice at early time points postinoculation, indicating that these mutations synergistically enhance safety of the vaccine candidate.

CONCLUSIONS

These data suggest that restriction of LAV replication in skeletal muscle enhances tolerability of reactogenic vaccine candidates and may improve the rational design of CHIKV vaccines.

Patients' perspectives of a pharmacist-provided clinical pharmacogenomics service

Aim: To assess the perspectives and experiences of patients who participated in a pharmacist-provided clinical pharmacogenomics (PGx) service. Methods: We conducted individual semistructured interviews with 16 patients who received a pharmacist-provided PGx service. Qualitative data were analyzed to identify pertinent themes. Results: The major themes identified were: heterogeneity of patient PGx experiences and preferences, pharmacists as appropriate providers of PGx services, considerations regarding the use of PGx results in routine healthcare, and perceived applications of PGx testing. Theme-derived considerations included the need to establish appropriate pre-genotyping expectations, individualize patient education, facilitate collaboration with patients' providers and sustainably update patients' PGx information over time. Conclusion: Patient-specific perspectives such as these are important to consider when providing clinical PGx services, with intention of optimizing patient experiences.

Household and climate factors influence Aedes aegypti presence in the arid city of Huaquillas, Ecuador

Arboviruses transmitted by Aedes aegypti (e.g., dengue, chikungunya, Zika) are of major public health concern on the arid coastal border of Ecuador and Peru. This high transit border is a critical disease surveillance site due to human movement-associated risk of transmission. Local level studies are thus integral to capturing the dynamics and distribution of vector populations and social-ecological drivers of risk, to inform targeted public health interventions. Our study examines factors associated with household-level Ae. aegypti presence in Huaquillas, Ecuador, while accounting for spatial and temporal effects. From January to May of 2017, adult mosquitoes were collected from a cohort of households (n = 63) in clusters (n = 10), across the city of Huaquillas, using aspirator backpacks. Household surveys describing housing conditions, demographics, economics, travel, disease prevention, and city services were conducted by local enumerators. This study was conducted during the normal arbovirus transmission season (January—May), but during an exceptionally dry year. Household level Ae. aegypti presence peaked in February, and counts were highest in weeks with high temperatures and a week after increased rainfall. Univariate analyses with proportional odds logistic regression were used to explore household social-ecological variables and female Ae. aegypti presence. We found that homes were more likely to have Ae. aegypti when households had interruptions in piped water service. Ae. aegypti presence was less likely in households with septic systems. Based on our findings, infrastructure access and seasonal climate are important considerations for vector control in this city, and even in dry years, the arid environment of Huaquillas supports Ae. aegypti breeding habitat.

Mosquito transmitted infectious diseases are a growing concern around the world. The yellow fever mosquito (Aedes aegypti) has been responsible for recent major outbreaks of disease, including dengue fever and Zika. This mosquito prefers to bite humans and lay its eggs in artificial containers such as water tanks and planters. This makes Ae. aegypti well suited to become established in growing urban areas. Controlling these mosquitoes has been an important way to reduce the risk of disease transmission. Studies that are undertaken to understand local factors that contribute to the continued survival of the mosquito can be used to inform control practices. We conducted a study in the largest Ecuadorian city on the border of Peru where we collected adult mosquitoes from houses and surveyed household members about their behaviors, perceptions, and housing infrastructure associated with the mosquito vector. Mosquitoes were most numerous in weeks with high temperatures and a week after increased rainfall. We found that houses that had unreliable water service were more likely have mosquitoes present, while houses that used septic systems were less likely to have mosquitoes present.

Preoperative diagnosis of intraductal papillary neoplasm of the bile duct with endoscopic ultrasound

Intraductal papillary mucinous neoplasm of the bile duct is a rare tumour only recently classified as a distinct pathological entity. These neoplasms, rarely encountered in clinical practice in the UK, are now considered to be important precursors for the development of cholangiocarcinoma. We present a histologically confirmed case of intraductal papillary neoplasm of the bile duct in a male patient and discuss the main radiographic manifestations of this rare condition across multiple imaging modalities, with an emphasis on the imaging features of endoscopic ultrasonography and its role in establishing the diagnosis.

0475 Reducing Dysfunctional Sleep-Related Cognitions Improves Nighttime Sleep and Daytime Consequences in Older Adults with Insomnia

Introduction

The long-term impact of addressing sleep-related cognitions, which is an important component of cognitive behavioral therapy for insomnia (CBTI), has not been established, particularly in older adults. We examined whether specific changes in sleep-related cognitions predicted long-term changes in sleep and other outcomes following CBTI in older adults.

Methods

We analyzed data from a randomized controlled trial testing CBTI in older veterans with insomnia (N=159, mean age 72 years). Sleep-related cognitions were assessed with the Dysfunctional Beliefs and Attitudes about Sleep scale (DBAS, subscales: Consequences, Worry/Helplessness, Sleep Expectations, Medication). Outcome measures included the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), sleep diary variables, Flinders Fatigue Scale (FFS), and Short Form-12 health-related quality of life (QOL). Analyses completed slope of change in DBAS subscales (baseline to post-treatment: T1) between CBTI and control with respect to slope of change in sleep and other outcomes from post-treatment to 6-months (T2).

Results

Compared to controls, the CBTI group had significantly stronger associations between improvement (T1) in DBAS-Consequences and subsequent (T2) improvement in PSQI (difference in slopes [DIS]=0.9, 95%CI=[.29, 1.43], p=0.004), ISI (DIS=1.1, 95%CI=[.18, 2.0], p=0.019), ESS (DIS=0.6, 95%CI=[.10, 1.18], p=0.020), and FFS (DIS=1.9, 95%CI=[.76, 3.09], p=0.001). The CBTI group also had significantly stronger associations between improvement in DBAS-Worry/Helplessness and subsequent improvements in PSQI, ISI, and FFS; improvement in DBAS-Medication and PSQI and ISI; and improvement in DBAS-Sleep Expectations and improved FFS. Slopes were not different between groups for sleep diary variables or QOL.

Conclusion

Significant improvements in sleep-related cognitions with CBTI across DBAS subscales in older adults predicted improvement in several outcomes of nighttime sleep and daytime consequences. These findings suggest the importance of addressing dysfunctional sleep-related cognitions for sustained improvement with CBTI in older adults

Support

The study was supported by VA Health Services, Research and Development (Alessi, IIR 08-295), National Institute on Aging (K23AG055668, Song), National Heart, Lung, and Blood Institute (K24HL 143055, Martin) of the National Institutes of Health and VA Greater Los Angeles Healthcare System, Geriatric Research, Education and Clinical Center.

0581 Characteristics of US Women Veterans with Sleep Apnea: Results of a National Survey of VA Healthcare Users

Introduction

Sleep apnea (SA) is the most commonly diagnosed sleep disorder among patients in the US Veterans Administration (VA). The dramatic rise in women receiving VA care makes it essential to understand the presentation and treatment of SA in women Veterans. We performed a nationwide survey about sleep among US women Veterans and compared characteristics of respondents with and without a self-reported history of SA diagnosis and treatment.

Methods

A survey was mailed to a random sample of 4000 women VA healthcare users. The survey included demographics, Insomnia Severity Index (ISI), Patient Health Questionnaire-4 (PHQ-4 depression/anxiety), Primary Care-Post-Traumatic Stress Disorder (PC-PTSD), RLS symptom presence, SA symptoms (snore loudly, observed breathing pauses), diagnosis of SA, and use of PAP therapy (APAP, BPAP, CPAP). We compared women with and without SA, and (among those with SA) women who did and did not use PAP, using Chi-square and t-tests.

Results

1,498 completed surveys were returned (mean age 51.6 years, range 18-105 years, 62% non-Hispanic White). 200 respondents (13.4%) reported diagnosed SA. Women with SA were older (p<.001), likely to be employed (p=.013), more likely to snore loudly (p<.001) and to have breathing pauses while asleep (p<.001). They also had higher ISI (p<.001), were more like to report RLS (p<.001) nightmares (p=.027), and had higher PHQ-4 (p<.001) and PC-PTSD (p<.001) scores. Among women with SA, 130 (65%) used PAP. Loud snorers (p<.001) and those with observed breathing pauses were more likely to use PAP (p<.001).

Conclusion

One in 7 women who receive VA care report diagnosed SA. Women with SA had more mental health symptoms and comorbid sleep problems. Most reported using PAP therapy, although the amount of use is unknown. Those with SA symptoms were more likely to use PAP. Future work is needed to understand barriers to diagnosis and treatment of SA among women Veterans.

Support

Funding: VA Quality Enhancement Research Initiative RRP12-189 (Martin); NIH/NHLBI K24 HL143055 (Martin).

0537 Cognitive Functioning Before and After Insomnia Treatment in Women Veterans

Introduction

Women are at higher risk for cognitive impairment and dementia compared to men. Identifying potentially treatable risk factors such as insomnia is an important clinical goal. In a trial comparing two behavioral treatments for insomnia in women veterans, we hypothesized that 1) worse baseline insomnia severity would be associated with poorer cognitive function, and 2) improvement in insomnia severity with treatment would be associated with improvement in cognitive functioning.

Methods

347 women veterans with insomnia disorder [mean age 48.3 (12.9) years] completed baseline testing. Of these, 149 women were randomized to receive cognitive behavioral therapy for insomnia (CBT-I) or acceptance and commitment (ACT) based insomnia treatment (both treatments included sleep restriction, stimulus control, and sleep hygiene). Insomnia Severity Index (ISI) was assessed at baseline, post-treatment, and 3-month follow-up. Cognitive functioning was measured with Symbol Digit Coding (SDC) and Trail Making Test A and B (TMTA and TMTB). Pearson correlations were used to examine associations between insomnia severity and cognitive functioning at baseline and changes in both insomnia severity and cognitive functioning from before to after treatment.

Results

At baseline (N=347), mean ISI was 14.1 (5.3). Worse baseline ISI was associated with worse baseline cognitive functioning on TMTA (r=-.15, p<.01) and SDC (r=-.12, p<.05). In the randomized sample (N=149), ISI scores improved at post-treatment (mean ISI change= -9.0; p<.001) and 3-month follow-up (mean change= -8.0; p<.001) relative to baseline. Improvement in ISI from baseline to post-treatment was significantly associated with improvement in SDC from baseline to post-treatment (r=-.18, p<.05), but not improvement in TMTA and TMTB. Change in ISI was not significantly related to change in cognitive tasks from baseline to 3-month follow-up.

Conclusion

More severe insomnia is associated with worse cognitive functioning in women veterans. The magnitude of improvement in insomnia symptoms may be associated with improvement in cognition.

Support

NIH/NIA K23AG049955 (PI: Dzierzewski); VA/HSR&D IIR-HX002300 (PI: Martin), NIH/NHLBI K24HL143055 (PI: Martin).

0644 An Educational and Behavioral Intervention Failed to Improve PAP Use Among Veterans With Spinal Cord Injuries and Diseases: Results of a Randomized Controlled Trial

Introduction

Sleep disordered breathing (SDB) is common among individuals with spinal cord injuries or diseases (SCI/D), many of whom are military Veterans, and physical limitations make use of positive airway pressure (PAP) therapy challenging. This study sought to test the effects of an educational and behavioral intervention to improve PAP adherence among Veterans with SCI/D over the first 3 months of use.

Methods

63 Veterans (mean age=60.7(10.2) years; 92% male) with SCI/D (33 SCI, 30 SCD; 25 cervical involvement; 38 thoracic and below) and SDB (23 with AHI 5-15; 40 with AHI≥15) who received PAP treatment (CPAP or BPAP) were randomly assigned to receive a comprehensive 3-month intervention (INT) or an equal attention control (EAC). INT and EAC both included 1 face-to-face session (week 1) and 5 additional telephone sessions (weeks 2, 3, 4, 8 and 12). Main outcome measures were PAP use over the first 3 months: nights of use, nights of use ≥4 hours, and mean hours of use per night. Repeated measures ANCOVA models were used to test the differences between INT and EAC over the first 3 months of treatment.

Results

Number of nights with ≥4 hours of use in months 1-3 was 9, 7, and 6 nights in the INT and 8, 5 and 4 nights in the EAC (p’s≥.37), respectively. There were no significant differences between INT and EAC for number of nights with any use (p’s≥.24), or mean hours of use per night (p’s≥.30). All 3 PAP use variables declined over time in both groups.

Conclusion

Sustained use of PAP therapy was difficult to achieve among those with SCI/D, and a 6-session behavioral intervention did not lead to significant improvements in use. Even when relatively high levels of initial use are achieved, this is difficult to sustain over time. Future studies should explore whether SCI/D patients experience significant symptom relief with PAP, and if so, whether home-based interventions or more intensive face-to-face PAP adherence programs will be effective.

Support

VA Rehabilitation Research and Development Service, Merit Review (1RX002116; PI: Badr); NIH/NHLBI K24 HL143055 (Martin).

0467 Benefits of CBT-I for Women Veterans with and without PTSD

Introduction

A quarter of women Veterans (WVs) receiving VA healthcare meet diagnostic criteria for both insomnia disorder and posttraumatic stress disorder (PTSD). Cognitive Behavioral Therapy for Insomnia (CBT-I) is effective at improving sleep among individuals with comorbid psychiatric conditions; however, no studies have examined the impact of CBT-I in women with insomnia plus PTSD. The current analyses examined changes in sleep symptoms, quality of life (QoL), and mental health symptoms from pre- to post-CBT-I in WVs with and without PTSD.

Methods

This was a secondary analysis of 75 WVs with insomnia (32 with probable PTSD), who received CBT-I within a behavioral sleep intervention study (NCT02076165). Measures completed at baseline, posttreatment, and 3-month follow-up included: insomnia severity (Insomnia Severity Index, ISI), sleep quality (Pittsburgh Sleep Quality Index, PSQI), PTSD symptoms (PTSD Checklist-5, PCL-5; probable PTSD=total score ≥33), depressive symptoms (Patient Health Qestionnaire-9, PHQ-9), and mental and physical quality of life (Short Form Health Survey, SF-12). One sample T-tests examined changes in ISI, PSQI, PHQ-9, PCL-5, and SF-12 from baseline to posttreatment and baseline to follow-up. Two samples T-tests compared change scores in ISI, PSQI, PHQ-9, and SF-12 between participants with and without PTSD.

Results

There were significant improvements in ISI (p≤.001), PSQI (p≤.001), PHQ-9 (p≤.001), PCL-5 (p=.001), and SF-12 mental (p≤.001) and physical (p=.03) from baseline to posttreatment and 3-month follow-up (p≤.001-.01). There were no significant change score differences between WVs with and without PTSD from baseline to posttreatment (p=.06-.98) or 3-month follow-up (p=.09-.93).

Conclusion

CBT-I appears to be an effective treatment to improve insomnia symptoms among WVs with and without PTSD, and may reduce psychiatric symptoms as well. These findings suggest WVs with comorbid insomnia and PTSD benefit from CBT-I. The appropriate sequencing of CBT-I and PTSD treatments remains potentially important, but unstudied.

Support

VA/HSR&D IIR-HX002300; NIH/NHLBI K24HL14305; VA Office of Academic Affiliations through the Advanced Fellowship Programs in HSR&D and Women’s Health

0131 Decreased Habitual Sleep Efficiency is Associated with Increased Insulin Resistance in Healthy Adult Men

Introduction

Partial sleep deprivation is associated with increased insulin resistance (IR), a metabolic disease risk marker. Little is known about habitual sleep patterns and IR in the absence of acute sleep restriction. We anticipated greater change in habitual sleep over one month would be associated with increased IR.

Methods

24 males (age=33.6±6.4 years; BMI=25.7±2.5kg/m2) completed baseline (T1) and follow-up (T2; ≥4 weeks post-T1) study procedures: actigraphy (one week) followed by polysomnography (PSG; one 10h sleep opportunity) and a next morning oral glucose tolerance test (OGTT; homeostatic model assessment insulin resistance [HOMA-IR], β-cell function [HOMA-β], and Matsuda Index). Weekly average actigraphy total sleep time (aTST; 291-511min) and sleep efficiency (aSE; 72–93%) were computed at T1 and T2, as well as across the 1, 2, and 3 days prior to PSG/OGTT. Pearson and Spearman correlations assessed the change (T1-T2) in actigraphy (aSEΔ, aTSTΔ, PSGΔ) or PSG sleep (PSG-TSTΔ, PSG-SEΔ, sleep stages) versus change in metabolic risk (HOMA-IRΔ, HOMA-βΔ, MatsudaΔ).

Results

There were significant correlations between HOMA-IRΔ and aSEΔ [r(22)=-0.42, p=0.01; rs=-0.45, p=0.03], PSG TSTΔ [r(22)=0.50, p=0.012; rs=0.41, p=.045], and PSG-SEΔ [r(22)=0.49, p=0.015; rs=0.43, p=.037]. No significant associations emerged between change in metabolic risk versus aTSTΔ one week prior to PSG/OGTT, aSEΔ or aTSTΔ across 1–3 days prior to PSG/OGTT, or PSG sleep stages.

Conclusion

Within-subject T1-T2 decrease in habitual sleep quality, but not TST, was associated with increased IR. T1-T2 PSG TST and SE were associated with following day IR. At home sleep 1–3 days beforehand were not correlated with IR. Although preceding night sleep quality and TST are associated with IR, habitual sleep quality, rather than TST, may be a more important determinant of metabolic risk in community dwelling middle-aged men.

Support

This work was supported by NIH/NHLBI R01HL124211, NIH/NHLBI K24HL138632, NIH National Center for Advancing Translational Sciences (NCATS) UCLA CTSI Grant UL1TR001881 (PI: Liu); and NIH/NHLBI K24HL143055 (PI: Martin). Dr. Kelly is supported by the VA Office of Academic Affiliations through the Advanced Fellowship Programs in Geriatrics.

0597 Precision of Sleep-Disordered Breathing Event Classification Using Simulated Home Sleep Apnea Testing in Patients with Spinal Cord Injury, or Disease

Introduction

Sleep-disordered breathing (SDB) is highly prevalent among patients with spinal cord injury or disease (SCI/D). In-laboratory polysomnography (PSG) is difficult for these patients due to functional limitations and the physical construction of most sleep laboratories. Our objective was to evaluate the concordance between simulated HSAT and PSG in identifying SDB severity and subtypes of respiratory events in this patient population.

Methods

Within a larger study, 33 Veterans with SCI/D completed one night of in-laboratory PSG. Limited-channel HSAT was simulated by extracting 5 channels from PSG signals to include nasal pressure, thermistor, thoracic and abdominal belts, and oxygen saturation.

Results

Mean age of patients was 59.8 ± 10.9 years; 87.9% were male, and the average BMI was 28.1 ± 6.3. The mean Apnea-Hypopnea Index (AHI) from PSG was 35.5 ± 22.7. The mean Respiratory Event Index (REI) based on simulated HSAT was 22.5 ± 18.6. Thirty-one patients (93.9%) had SDB defined as AHI ≥5/hour. Simulated limited-channel HSAT accurately identified 32 out of 33 patients (96.96%). When SDB was further classified into mild (AHI 5-15 events/hr), moderate (AHI 15-30 events/hr), and severe (AHI>30/hr), simulated HSAT consistently underestimated the severity of underlying SDB. Spearman correlation between estimating AHI (PSG-HSAT) and subtypes of respiratory events was primarily accounted for by the difference in the number of hypopneas (r=0.72, -0.021 and -0.001 for hypopneas, obstructive and central apneas, respectively).

Conclusion

Our findings support the diagnostic utility of HSAT in SCI/D patients with SDB; however, HSAT underestimation of SDB may lead to difficulties in optimizing therapy. The misclassification of SDB severity is mainly driven by the number of hypopneas. Classification of hypopneas as obstrcutive or central may shed further light on the nature of this difference. Further research on the usability of HSAT devices in this patient population is needed.

Support

VA Rehabilitation Research and Development Service (RX002116; PI Badr and RX002885; PI Sankari) and NIH/NHLBI (K24HL143055; PI: Martin)

Acute psychological stress increases serum circulating cell-free mitochondrial DNA

Intrinsic biological mechanisms transduce psychological stress into physiological adaptation that requires energy, but the role of mitochondria and mitochondrial DNA (mtDNA) in this process has not been defined in humans. Here, we show that similar to physical injury, exposure to psychological stress increases serum circulating cell-free mtDNA (ccf-mtDNA) levels. Healthy midlife adults exposed on two separate occasions to a brief psychological challenge exhibited a 2-3-fold increase in ccf-mtDNA, with no change in ccf-nuclear DNA levels, establishing the magnitude and specificity for ccf-mtDNA reactivity. In cell-based studies, we show that glucocorticoid signaling - a consequence of psychological stress in humans - is sufficient to induce mtDNA extrusion in a time frame consistent with stress-induced ccf-mtDNA increase. Collectively, these findings provide evidence that acute psychological stress induces ccf-mtDNA and implicate neuroendocrine signaling as a potential trigger for ccf-mtDNA release. Further controlled work is needed to confirm that observed increases in ccf-mtDNA result from stress exposure and to determine the functional significance of this effect.

A framework for uncertainty and risk analysis in Total Maximum Daily Load applications

In the United States, the computation of Total Maximum Daily Loads (TMDL) must include a Margin of Safety (MOS) to account for different sources of uncertainty. In practice however, TMDL studies rarely include an explicit uncertainty analysis and the estimation of the MOS is often subjective and even arbitrary. Such approaches are difficult to replicate and preclude the comparison of results between studies. To overcome these limitations, a Bayesian framework to compute TMDLs and MOSs including an explicit evaluation of uncertainty and risk is proposed in this investigation. The proposed framework uses the concept of Predictive Uncertainty to calculate a TMDL from an equation of allowable risk of non-compliance of a target water quality standard. The framework is illustrated in a synthetic example and in a real TMDL study for nutrients in Sawgrass Lake, Florida.

The Common Sense of Counseling Psychology: Introducing the Common-Sense Model of Self-Regulation

The goal of therapy is typically to improve clients' self-management of their problems, not only during the course of therapy but also after therapy ends. Although it seems obvious that therapists are interested in improving client's self-management, the psychotherapy literature has little to say on the topic. This article introduces Leventhal's Common-Sense Model of Self-Regulation, a theoretical model of the self-management of health, and applies the model to the therapeutic process. The Common-Sense Model proposes that people develop illness representations of health threats and these illness representations guide self-management. The model has primarily been used to understand how people self-manage physical health problems, we propose it may also be useful to understand self-management of mental health problems. The Common-Sense Model's strengths-based perspective is a natural fit for the work of counseling psychologists. In particular, the model has important practical implications for addressing how clients understand mental health problems over the course of treatment and self-manage these problems during and after treatment.

Wetlands for Wastewater Treatment

An update on the current research and development of the treatment technologies, which utilize natural processes or passive components in wastewater treatment, is provided in this paper. The main focus is on wetland systems and their applications in wastewater treatment (as an advanced treatment unit or decentralized system), nutrient and pollutant removal (metals, industrial and emerging pollutants including pharmaceutical compounds). A summary of studies involving the effects of vegetation, wetland design and modeling, hybrid and innovative systems, storm water treatment and pathogen removal is also included.

Wetlands for Wastewater Treatment

This paper provides a review of the treatment technologies, which utilize natural processes or passive components in wastewater treatment. In particular, this paper primarily focuses on wetland systems and their applications in wastewater treatment (as an advanced treatment unit or decentralized system), nutrient and pollutant removal (single and multiple pollutants, and metals), and emerging pollutant removal (pharmaceuticals). A summary of studies involving the plant (vegetation) effects, wetland design and modeling, hybrid and innovative systems, storm water treatment and pathogen removal is also included.

A red tide of Alexandrium fundyense in the Gulf of Maine

In early July 2009, an unusually high concentration of the toxic dinoflagellate Alexandrium fundyense occurred in the western Gulf of Maine, causing surface waters to appear reddish brown to the human eye. The discolored water appeared to be the southern terminus of a large-scale event that caused shellfish toxicity along the entire coast of Maine to the Canadian border. Rapid-response shipboard sampling efforts together with satellite data suggest the water discoloration in the western Gulf of Maine was a highly ephemeral feature of less than two weeks in duration. Flow cytometric analysis of surface samples from the red water indicated the population was undergoing sexual reproduction. Cyst fluxes downstream of the discolored water were the highest ever measured in the Gulf of Maine, and a large deposit of new cysts was observed that fall. Although the mechanisms causing this event remain unknown, its timing coincided with an anomalous period of downwelling-favorable winds that could have played a role in aggregating upward-swimming cells. Regardless of the underlying causes, this event highlights the importance of short-term episodic phenomena on regional population dynamics of A. fundyense.

Abstract P5-07-05: Insulin-like growth factor binding protein-3 is a key component of the breast cancer cell response to DNA-damaging therapy

Introduction. Breast cancer cells frequently develop resistance to DNA-damaging therapies, such as radiation and the cytotoxic drugs doxorubicin and etoposide, and activation of the epidermal growth factor receptor (EGFR) may play an important role in this process. However many estrogen receptor (ER)-negative breast tumors respond poorly to DNA-damaging drugs even when combined with an EGFR inhibitor. EGFR can modulate the repair of DNA double strand breaks (DSB) by non-homologous end-joining (NHEJ), by forming protein complexes that include the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). In previous studies we have shown that the growth-regulatory protein, insulin-like growth factor binding protein-3 (IGFBP-3), can translocate to the nucleus, is a substrate for DNA-PKcs, and can transactivate EGFR. The aim of this study was to delineate the role of IGFBP-3 in the response of breast cancer cells to DSB-inducing chemotherapeutic agents.

Results. In the triple-negative breast cancer cell lines MDA-MB-468 and Hs578T, which express IGFBP-3 highly, nuclear localization of EGFR and IGFBP-3, and of their complex as measured by coimmunoprecipitation (coIP), was enhanced by exposure to etoposide or doxorubicin, peaking 2 h after etoposide treatment. This effect was blocked by the EGFR kinase inhibitor gefitinib. Concomitantly, the co-location of EGFR-IGFBP-3 complexes with lipid rafts, visualized by proximity ligation assay (PLA) and confocal microscopy, decreased in response to drug treatment, consistent with the loss of this complex from the plasma membrane. Similar to the nuclear DNA-PKcs-EGFR complex, the nuclear DNA-PKcs-IGFBP-3 complex (seen by both coIP and PLA) was greatest 4 h after treatment. DNA-PKcs activation at serine-2056, required for the repair of DNA DSB and stimulated by etoposide treatment, was decreased by IGFBP-3 downregulation using two separate siRNAs, and this treatment also attenuated the enhanced DNA-PKcs-EGFR complexes seen in response to etoposide. Collectively these data suggest that IGFBP-3 has an obligatory role in the DNA repair response to DNA-damaging therapy through its interactions with EGFR and DNA-PKcs.

Conclusion. IGFBP-3 co-translocation to the nucleus of breast cancer cells and its complex formation with DNA-PKcs and EGFR in response to DNA damage demonstrate its previously unrecognized involvement in the regulation of DNA DSB repair by NHEJ. These novel findings suggests the possibility of a therapeutic approach for sensitizing ER-negative breast cancers to chemo- or radiotherapy by targeting the DNA repair function of IGFBP-3. Supported by the Australian Research Council.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-07-05.

Physiology and Endocrinology Symposium: Nutritional aspects of developing replacement heifers

Studies in numerous species provide evidence that diet during development can mediate physiological changes necessary for puberty. In cattle, several studies have reported inverse correlations between postweaning growth rate and age at puberty and heifer pregnancy rates. Thus, postweaning growth rate was determined to be an important factor affecting age of puberty, which in turn influences pregnancy rates. This and other research conducted during the late 1960s through the early 1980s indicated puberty occurs at a genetically predetermined size, and only when heifers reach their target BW can increased pregnancy rates be obtained. Guidelines were established indicating replacement heifers should achieve 60 to 65% of their expected mature BW by breeding. Traditional approaches for postweaning development of replacement heifers used during the last several decades have primarily focused on feeding heifers to achieve or exceed an appropriate target BW and thereby maximize heifer pregnancy rates. Intensive heifer development systems may maximize pregnancy rates, but not necessarily optimize profit or sustainability. Since inception of target BW guidelines, subsequent research demonstrated that the growth pattern heifers experience before achieving a critical target BW could be varied. Altering rate and timing of BW gain can result in compensatory growth periods, providing an opportunity to decrease feed costs. Recent research has demonstrated that feeding replacement heifers to traditional target BW increased development costs without improving reproduction or subsequent calf production relative to development systems in which heifers were developed to lighter target BW ranging from 50 to 57% of mature BW.

Nogo-A knockdown inhibits hypoxia/reoxygenation-induced activation of mitochondrial-dependent apoptosis in cardiomyocytes

Programmed cell death of cardiomyocytes following myocardial ischemia increases biomechanical stress on the remaining myocardium, leading to myocardial dysfunction that may result in congestive heart failure or sudden death. Nogo-A is well characterized as a potent inhibitor of axonal regeneration and plasticity in the central nervous system, however, the role of Nogo-A in non-nervous tissues is essentially unknown. In this study, Nogo-A expression was shown to be significantly increased in cardiac tissue from patients with dilated cardiomyopathy and from patients who have experienced an ischemic event. Nogo-A expression was clearly associated with cardiomyocytes in culture and was localized predominantly in the endoplasmic reticulum. In agreement with the findings from human tissue, Nogo-A expression was significantly increased in cultured neonatal rat cardiomyocytes subjected to hypoxia/reoxygenation. Knockdown of Nogo-A in cardiomyocytes markedly attenuated hypoxia/reoxygenation-induced apoptosis, as indicated by the significant reduction of DNA fragmentation, phosphatidylserine translocation, and caspase-3 cleavage, by a mechanism involving the preservation of mitochondrial membrane potential, the inhibition of ROS accumulation, and the improvement of intracellular calcium regulation. Together, these data demonstrate that knockdown of Nogo-A may serve as a novel therapeutic strategy to prevent the loss of cardiomyocytes following ischemic/hypoxic injury.

Surgeon opinion on new technologies in orthopaedic surgery

Technological advances such as computer navigation systems and robotics, including support systems for minimally invasive surgery, have the potential to revolutionise how orthopaedic surgery is carried out. However uptake has so far been limited. Increased awareness of user requirements in adoption decision-making will be useful. In this regard, the opinion of the individual surgeon regarding his or her willingness to engage in a novel technology has rarely been garnished. This paper analyses the opinions of orthopaedic consultants from the UK and USA about technological advances in hip and knee arthroplasty, factors contributing to successful short-term and long-term surgical outcome, and patient preferences. The survey, using a web-based questionnaire, was carried out in 2006-2007 and followed up in 2010. The results of this research give a greater insight into why surgical technologies that have the potential to improve patient outcome are not more speedily adopted in the health service.

Dendritic spine alterations in neocortical pyramidal neurons following postnatal neuronal Nogo-A knockdown

The myelin-associated protein Nogo-A is a well-known inhibitor of axonal regeneration and compensatory plasticity, yet functions of neuronal Nogo-A are not as clear. The present study examined the effects of decreased levels of neuronal Nogo-A on dendritic spines of developing neocortical neurons. Decreased Nogo-A levels in these neurons resulted in lowered spine density and an increase in filopodial type protrusions. These results suggest a role for neuronal Nogo-A in maintaining a spine phenotype in neocortical pyramidal cells.

Femtosecond spectroscopy of electron transfer in the reaction center of the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26: Direct electron transfer from the dimeric bacteriochlorophyll primary donor to the bacteriopheophytin acceptor with a time constant of 2.8 +/- 0.2 psec

The primary light-induced charge separation in reaction centers from Rhodopseudomonas sphaeroides R-26 has been investigated after excitation with laser pulses of 150 fsec duration within the longwave absorption band of the primary donor at 850 nm. An excited state of the primary donor, characterized by a broad absorption spectrum extending over the whole spectral range investigated (545-1240 nm), appeared within 100 fsec and gave rise to stimulated emission in the 870- to 1000-nm region with a 2.8-psec lifetime. The photooxidation of the primary donor, as measured at 1240 nm, and the photoreduction of the bacteriopheophytin acceptor, monitored at 545 nm and 675 nm, have been found to proceed simultaneously with a time constant of 2.8 +/- 0.2 psec. Kinetics of absorbance changes at other probe wavelengths gave no indication that an accessory bacteriochlorophyll is involved as a transient electron acceptor.

Femtosecond spectroscopy of excitation energy transfer and initial charge separation in the reaction center of the photosynthetic bacterium Rhodopseudomonas viridis

Reaction centers from the photosynthetic bacterium Rhodopseudomonas viridis have been excited within the near-infrared absorption bands of the dimeric primary donor (P), of the "accessory" bacteriochlorophylls (B), and of the bacteriopheophytins (H) by using laser pulses of 150-fsec duration. The transfer of excitation energy between H, B, and P occurs in slightly less than 100 fsec and leads to the ultrafast formation of an excited state of P. This state is characterized by a broad absorption spectrum and exhibits stimulated emission. It decays in 2.8 +/- 0.2 psec with the simultaneous oxidation of the primary donor and reduction of the bacteriopheophytin acceptor, which have been monitored at 545, 675, 815, 830, and 1310 nm. Although a transient bleaching relaxing in 400 +/- 100 fsec is specifically observed upon excitation and observation in the 830-nm absorption band, we have found no indication that an accessory bacteriochlorophyll is involved as a resolvable intermediary acceptor in the primary electron transfer process.

Effect of dietary crude protein source on hormone and follicle characteristics in beef heifers

Ground, raw soybeans (SB), or dried distillers grain plus solubles (DDGS) were utilized in heifer development diets to determine the effect of dietary fat and protein source on hormone and follicle characteristics and ADG. The experiment was conducted over 2 yr with 100 June-born heifers (199 +/- 2 kg initial BW, n = 50 per yr). The experimental periods were 157 and 207 d in yr 1 and 2, respectively. Heifers were provided a dietary supplement (DM basis) of 1.23 kg of SB and 0.40 kg of corn or 1.65 kg of DDGS between weaning and breeding. Estrus was synchronized with 2 injections of PGF(2alpha) 14 d apart. Dominant follicles were measured and aspirated via transvaginal ultrasonography 60 h after the second PGF(2alpha) injection. Heifers were exposed to bulls beginning 14 d after aspiration for 45 d. Heifer ADG was greater (P = 0.02) for DDGS heifers in yr 1, but was similar (P = 0.47) in yr 2. However, there was no difference (P = 0.35) in final BW in either year. There was no difference (P >or= 0.67) in follicle size, follicle hormone concentrations, or pregnancy rate (88%) between yr 1 and 2. Serum estrogen at 48 or 60 h after PGF(2alpha) injection were similar (P >or= 0.91); however, LH at 60 h in yr 2 tended to be greater (P = 0.07) for DDGS heifers. The percentage of heifers experiencing an LH surge 48 and 60 h after PGF(2alpha) injection was not affected (P >/= 0.40) by treatment. Calf production was not affected (P >or= 0.20) by developmental diet. In summary, DDGS and SB have similar effects on hormone and follicle characteristics at the inclusion rates used in these studies.

Lower predation risk for migratory birds at high latitudes

Quantifying the costs and benefits of migration distance is critical to understanding the evolution of long-distance migration. In migratory birds, life history theory predicts that the potential survival costs of migrating longer distances should be balanced by benefits to lifetime reproductive success, yet quantification of these reproductive benefits in a controlled manner along a large geographical gradient is challenging. We measured a controlled effect of predation risk along a 3350-kilometer south-north gradient in the Arctic and found that nest predation risk declined more than twofold along the latitudinal gradient. These results provide evidence that birds migrating farther north may acquire reproductive benefits in the form of lower nest predation risk.

Mechanisms, chemical structures and drug metabolism

From the studies that have been done by many laboratories over the last 2 decades, it is now clear that the toxicities produced by many drugs are due to their reactive metabolites. It is though that, in many cases, reactive metabolites cause toxicity by binding covalently to tissue proteins. However, until recently it was difficult to identify these protein targets. Due to the development of an immunochemical approach, this problem has been overcome, as is illustrated here by studies that have been conducted on the metabolic basis of the idiosyncratic hepatitis caused by the inhalation anaesthetic halothane. The major problem to solve in the future will be to determine how protein adduct formation leads to toxicity. It is possible that protein adduct formation may alter an important cellular function or may lead to immunopathology, as is thought to occur in the case of halothane hepatitis. If an allergic reaction is suspected, purified protein targets of reactive metabolites can serve as antigens for identifying sensitized individuals. This information can be used to prevent not only an allergic reaction to the drug, but possible cross-reactions to other drugs that are structurally related. Another important application of these studies is the design of safer alternative drugs that will not produce structurally similar toxic reactive metabolites.

Winter grazing system and supplementation during late gestation influence performance of beef cows and steer progeny

A 2 x 2 factorial study evaluated effects of cow wintering system and last trimester CP supplementation on performance of beef cows and steer progeny over a 3-yr period. Pregnant composite cows (Red Angus x Simmental) grazed winter range (WR; n = 4/yr) or corn residue (CR; n = 4/yr) during winter and within grazing treatment received 0.45 kg/d (DM) 28% CP cubes (PS; n = 4/yr) or no supplement (NS; n = 4/yr). Offspring steer calves entered the feedlot 14 d postweaning and were slaughtered 222 d later. Precalving BW was greater (P = 0.02) for PS than NS cows grazing WR, whereas precalving BCS was greater (P < 0.001) for cows grazing CR compared with WR. Calf birth BW was greater (P = 0.02) for CR than WR and tended to be greater (P = 0.11) for PS than NS cows. Prebreeding BW and BCS were greater (P <or= 0.001) for CR than WR cows and PS than NS (P = 0.006) cows. At weaning, CR cows were heavier (P < 0.001) than WR cows but had similar BCS (P = 0.74). Cow weaning BW and BCS were not affected (P > 0.32) by PS. Calf weaning BW was less (P = 0.01) for calves from NS cows grazing WR compared with all other treatments. Pregnancy rate was unaffected by treatment (P > 0.39). Steer ADG, 12th-rib fat, yield grade, and LM area (P > 0.10) were similar among all treatments. However, final BW and HCW (P = 0.02) were greater for steers from PS-WR than NS-WR cows. Compared with steers from NS cows, steers from PS cows had greater marbling scores (P = 0.004) and a greater (P = 0.04) proportion graded USDA Choice or greater. Protein supplementation of dams increased the value of calves at weaning (P = 0.03) and of steers at slaughter regardless of winter grazing treatment (P = 0.005). Calf birth and weaning BW were increased by grazing CR during the winter. Calf weaning BW was increased by PS of the dam if the dam grazed WR. Compared with steers from NS cows, steer progeny from PS cows had a greater quality grade with no (P = 0.26) effect on yield grade. These data support a late gestation dam nutrition effect on calf production via fetal programming.

Crystallization and preliminary diffraction analysis of a DsbA homologue from Wolbachia pipientis

alpha-DsbA1 is one of two DsbA homologues encoded by the Gram-negative alpha-proteobacterium Wolbachia pipientis, an endosymbiont that can behave as a reproductive parasite in insects and as a mutualist in medically important filarial nematodes. The alpha-DsbA1 protein is thought to be important for the folding and secretion of Wolbachia proteins involved in the induction of reproductive distortions. Crystals of native and SeMet alpha-DsbA1 were grown by vapour diffusion and belong to the monoclinic space group C2, with unit-cell parameters a = 71.4, b = 49.5, c = 69.3 A, beta = 107.0 degrees and one molecule in the asymmetric unit (44% solvent content). X-ray data were recorded from native crystals to a resolution of 2.01 A using a copper anode and data from SeMet alpha-DsbA1 crystals were recorded to 2.45 A resolution using a chromium anode.

Effect of prebreeding body weight or progestin exposure before breeding on beef heifer performance through the second breeding season

Two experiments evaluated prebreeding target BW or progestin exposure for heifers developed lighter than traditional recommendations. Experiment 1 evaluated the effects of the system on heifer performance through subsequent calving and rebreeding over 3 yr. Heifers (229 kg) were assigned randomly to be developed to 55% of mature BW (299 kg) before a 45-d breeding season (intensive, INT; n = 119) or 50% of mature BW (272 kg) before a 60-d breeding season (relaxed, RLX; n = 142). Prebreeding and pregnancy diagnosis BW were greater (P <or= 0.006) for INT than RLX heifers. Overall pregnancy rate did not differ (88.4%; P = 0.51), but RLX heifers had later calving dates (7 d; P < 0.001) and lighter calf weaning weights (194 +/- 4 vs. 199 +/- 4 kg; P < 0.07) compared with INT heifers. Calf birth weight, calving difficulty, second-calf conception rates, and 2-yr-old retention rate did not differ (P > 0.15) between systems. Cost per pregnant 2-yr-old cow was less for the RLX than the INT heifer development system. Of heifers that failed to become pregnant, a greater proportion (P = 0.07) of heifers in the RLX than in the INT system were prepubertal when the breeding season began. Therefore, a second 2-yr experiment evaluated melengestrol acetate (MGA, 0.5 mg/d) as a means of hastening puberty in heifers developed to 50% of mature BW. Heifers were assigned randomly to the control (n = 103) or MGA (n = 81) treatment for 14 d and were placed with bulls 13 d later for 45 d. Prebreeding and pregnancy diagnosis BW were similar (280 and 380 kg, respectively; P > 0.10) for heifers in the control and MGA treatments. The proportion of heifers pubertal before breeding (74%), pregnancy rate (90%), calving date, calf weaning weight, and second breeding season pregnancy rate (92%) were similar (P > 0.10) between treatments. Developing heifers to 50 or 55% of mature BW resulted in similar overall pregnancy rates, and supplementing the diets of heifers developed to 50% of mature BW with MGA before breeding did not improve reproductive performance.

Expression and crystallization of DsbA from Staphylococcus aureus

Bacterial Dsb proteins catalyse the in vivo formation of disulfide bonds, a critical step in the stability and activity of many proteins. Most studies on Dsb proteins have focused on Gram-negative bacteria and thus the process of oxidative folding in Gram-positive bacteria is poorly understood. To help elucidate this process in Gram-positive bacteria, DsbA from Staphylococcus aureus (SaDsbA) has been focused on. Here, the expression, purification, crystallization and preliminary diffraction analysis of SaDsbA are reported. SaDsbA crystals diffract to a resolution limit of 2.1 A and belong to the hexagonal space group P6(5) or P6(1), with unit-cell parameters a = b = 72.1, c = 92.1 A and one molecule in the asymmetric unit (64% solvent content).

Towards time-resolved diffraction studies with glycogen phosphorylase

Laue diffraction with high intensity, broad-spectrum synchrotron radiation sources allows three-dimensional data sets on protein crystals to be recorded in seconds or milliseconds and opens the way for time-resolved studies on dynamic events in crystals. This chapter briefly reviews the field and describes progress towards time-resolved studies with glycogen phosphorylase. Methods for the synchronization of the start of reaction with the start of data collection have been developed for the phosphorolytic reaction of glycogen phosphorylase. The compound 3,5-dinitrophenylphosphate is photolabile, yielding Pi and the by-product, 3,5-dinitrophenol, which is non-reactive with the enzyme. Spectroscopic studies show that the compound has good quantum yield and that photolysis is rapid (greater than 1000 s-1). Release of the dinitrophenylate anion, following a pulse of light from a xenon flash lamp, has been monitored with a diode array spectrophotometer specially adapted for measurements on crystals. In a laboratory X-ray experiment with crystals of glycogen phosphorylase b, release of Pi and formation of the enzyme-product complex have been demonstrated. The way is now open for Laue diffraction studies on the catalytic reaction in the crystal.

Utilization of dried distillers grains for developing beef heifers1,2,3

A 2-yr study was conducted at 2 locations to determine if supplementing beef heifers with dried distillers grains (DDG) as an energy source affected growth or reproduction. Spring-born crossbred heifers (n = 316) were blocked by age or sire and age and assigned randomly to DDG or control (dried corn gluten feed, whole corn germ, urea) supplement. Heifers received prairie hay in amounts sufficient for ad libitum intake and 0.59% of BW DDG or 0.78% of BW control supplement (DM basis). Supplements were formulated to be isocaloric, but protein degradability differed. Supplemental undegradable intake protein intake from DDG averaged 267 g/animal daily and reached 318 g/animal daily; control supplemental undegradable intake protein intake averaged 90 g/animal daily and peaked at 107 g/animal daily. Initial pubertal status was determined by 2 blood samples collected 10 d apart, and monthly BW were collected from November through January; then biweekly BW and blood samples were collected from February until May yearly. Heifers were synchronized with 2 injections of PGF2alpha 14 d apart; estrus was detected and heifers were artificially inseminated for 5 d and placed with bulls 10 d later. Conception and pregnancy rates were determined via transrectal ultrasonography. Initial age, BW, and BCS did not differ (P > 0.92) for control and DDG heifers. Final BW, ADG, and final BCS also were not affected (P > 0.31) by supplementation. Estimated age and BW at puberty did not differ (P > 0.23) between treatments, and the proportions of pubertal heifers did not differ at the initiation of the experiment (P > 0.82), at the beginning of the 14-d sampling intervals, or before synchronization. Estrus synchronization rate (75.9%), time of estrus, and overall pregnancy rate (89.5%) were not affected (P > 0.14) by treatment. However, a greater proportion (P = 0.008) of DDG than control heifers conceived to AI (75.0 vs. 52.9%), resulting in greater (P = 0.07) AI pregnancy rates for DDG heifers (57.0 vs. 40.1%). Body weight or BCS at pregnancy diagnosis did not differ (P > 0.52) between DDG and control heifers. Supplementing beef heifers with DDG during development did not affect age at puberty but improved AI conception and pregnancy rates compared with an isocaloric control supplement.

Effects of dam nutrition on growth and reproductive performance of heifer calves1

A 3-yr study was conducted with heifers (n = 170) whose dams were used in a 2 x 2 factorial arrangement of treatments to determine the effects of late gestation (LG) or early lactation (EL) dam nutrition on subsequent heifer growth and reproduction. In LG, cows received 0.45 kg/d of a 42% CP supplement (PS) or no supplement (NS) while grazing dormant Sandhills range. During EL, cows from each late gestational treatment were fed cool-season grass hay or grazed sub-irrigated meadow. Cows were managed as a single herd for the remainder of the year. Birth date and birth weight of heifer calves were not affected (P > 0.10) by dam nutrition. Meadow grazing and PS increased (P = 0.02; P = 0.07) heifer 205-d BW vs. feeding hay and NS, respectively. Weight at prebreeding and pregnancy diagnosis were greater (P < 0.04) for heifers from PS dams but were unaffected by EL nutrition (P > 0.10). There was no effect (P > 0.10) of LG or EL dam nutrition on age at puberty or the percentage of heifers cycling before breeding. There was no difference (P > 0.10) in pregnancy rates due to EL treatment. Pregnancy rates were greater (P = 0.05) for heifers from PS dams, and a greater proportion (P = 0.005) of heifers from PS dams calved in the first 21 d of the heifers' first calving season. Nutrition of the dams did not influence (P < 0.10) heifers' average calving date, calving difficulty, and calf birth weight during the initial calving season. Weight at the beginning of the second breeding season was greater (P = 0.005) for heifers from PS dams but was not affected by maternal nutrition during EL (P > 0.10). Dam nutrition did not affect (P > 0.10) heifer ADG or G:F ratio. Heifers from PS dams had greater DMI (P = 0.09) and residual feed intake (P = 0.07) than heifers from NS cows if their dams were fed hay during EL but not if their dams grazed meadows. Heifers born to PS cows were heavier at weaning, prebreeding, first pregnancy diagnosis, and before their second breeding season. Heifers from cows that grazed meadows during EL were heavier at weaning but not postweaning. Despite similar ages at puberty and similar proportions of heifers cycling before the breeding season, a greater proportion of heifers from PS dams calved in the first 21 d of the heifers' first calving season, and pregnancy rates were greater compared with heifers from NS dams. Collectively, these results provide evidence of a fetal programming effect on heifer postweaning BW and fertility.

Asynchronous administration of xenon and hypothermia significantly reduces brain infarction in the neonatal rat

BACKGROUND

Neonatal asphyxia causes long-term neurological and behavioural impairment in the developing brain. Concurrent administration of xenon and hypothermia synergistically reduces long-term damage in a rat model of neonatal asphyxia. This study sought to investigate whether asynchronous administration of xenon and hypothermia is capable of combining synergistically to provide neuroprotection.

METHODS

Seven-day-old rats were subjected to right common carotid artery occlusion followed by 90 min hypoxia with 8% oxygen. After a 1 h recovery period, rats received asynchronous administration of mild hypothermia (35 degrees C) and xenon (20%) with a 1 or 5 h gap between interventions, xenon (20%) alone, or mild hypothermia (35 degrees C) alone. Infarct volume in the brain was measured 4 days after injury.

RESULTS

Administration of hypothermia or xenon alone, 1 and 6 h after the hypoxic ischaemic insult, respectively, provided no neuroprotection. Asynchronous administration of xenon and hypothermia at a 1 h interval produced a significant reduction in infarct volume [93 (7) vs 74 (8); P < 0.05]. Reduction in infarct volume was also present when hypothermia and xenon were asynchronously administered with an intervening gap of 5 h [97 (5) vs 83 (3); P < 0.05].

CONCLUSIONS

This finding provides a rationale for investigating the combined use of hypothermia and xenon in a progressive manner for the management of neonatal asphyxia. Thus, hypothermia can be administrated at the site of delivery and xenon can be administered later.

Effects of supplementation of whole corn germ on reproductive performance, calf performance, and leptin concentration in primiparous and mature beef cows

A 2-yr study using primiparous and multiparous, spring-calving, crossbred beef cows was conducted to evaluate the effects of supplemental whole corn germ on reproductive performance, calf performance, and serum leptin concentrations. Each year, cows were blocked by age and BCS and assigned randomly to one of three treatments: PRE (n = 115) cows received 1.14 kg/d (DM basis) of whole corn germ for approximately 45 d before calving; POST (n = 109) cows were fed 1.14 kg/d of whole corn germ for approximately 45 d after calving; and control cows (n = 118) were fed similar energy and protein from dry-rolled corn (1.82 kg of DM/d) for 45 d before and after calving. Additionally, PRE cows were grouped with controls after calving, and POST cows were grouped with control cows before calving, so that corn germ-supplemented cows received the control supplement in the alternate feeding period. Cow BW (538 +/- 13 kg) and BCS (5.4 +/- 0.13) did not differ among treatments at any time during the experiment. Calf birth weight (39 +/- 2 kg), weaning weight (225 +/- 7 kg), and age-adjusted weaning weight (234 +/- 8 kg) did not differ because of dam supplementation regimen. Treatment did not affect the proportion of cows exhibiting ovarian luteal activity before the start of the breeding season (67%) or pregnancy rate (91%). The interval from exposure to bulls until subsequent calving did not differ (P = 0.16) among PRE (298 +/- 2.3 d), POST (303 +/- 2.6 d), and control (304 +/- 2.3 d) cows. Leptin concentrations did not differ among treatments and were 2.15 +/- 0.75, 1.88 +/- 0.76, and 1.91 +/- 0.75 ng/mL for control, POST, and PRE cows, respectively. Age and week relative to calving influenced leptin concentration. Primiparous cows had similar leptin concentrations to 3-yr-old and mature cows for wk -7 and -6 relative to calving, but lower (P < 0.10) concentrations than mature cows for wk -5, and lower (P < 0.05) concentrations than either 3-yr-old or mature cows for wk -4 to +7 relative to calving. Serum leptin was correlated with BCS (P < 0.0001; r = 0.35) at initiation of the feeding period and was correlated with BCS (P = 0.02; r = 0.12) and weight (P < 0.01; r = 0.14) at the completion of the supplement period, but it was not correlated with initial BW or interim BCS. Calving interval was not correlated (P > 0.12) with weekly measures of serum leptin concentration. Supplementing beef cows with whole corn germ had no effect on cow performance, calf performance, or serum leptin concentrations of cows.