Association of Rurality With Risk of Heart Failure

Importance

Rural populations experience an increased burden of heart failure (HF) mortality compared with urban populations. Whether HF incidence is greater among rural individuals is less known. Additionally, the intersection between racial and rural health inequities is understudied.

Objective

To determine whether rurality is associated with increased risk of HF, independent of cardiovascular (CV) disease and socioeconomic status (SES), and whether rurality-associated HF risk varies by race and sex.

Design, Setting, and Participants

This prospective cohort study analyzed data for Black and White participants of the Southern Community Cohort Study (SCCS) without HF at enrollment who receive care via Centers for Medicare & Medicaid Services (CMS). The SCCS is a population-based cohort of low-income, underserved participants from 12 states across the southeastern United States. Participants were enrolled between 2002 and 2009 and followed up until December 31, 2016. Data were analyzed from October 2021 to November 2022.

Exposures

Rurality as defined by Rural-Urban Commuting Area codes at the census-tract level.

Main Outcomes and Measures

Heart failure was defined using diagnosis codes via CMS linkage through 2016. Incidence of HF was calculated by person-years of follow-up and age-standardized. Sequentially adjusted Cox proportional hazards regression models tested the association between rurality and incident HF.

Results

Among 27 115 participants, the median (IQR) age was 54 years (47-65), 18 647 (68.8%) were Black, and 8468 (32.3%) were White; 5556 participants (20%) resided in rural areas. Over a median 13-year follow-up, age-adjusted HF incidence was 29.6 (95% CI, 28.9-30.5) per 1000 person-years for urban participants and 36.5 (95% CI, 34.9-38.3) per 1000 person-years for rural participants (P < .001). After adjustment for demographic information, CV risk factors, health behaviors, and SES, rural participants had a 19% greater risk of incident HF (hazard ratio [HR], 1.19; 95% CI, 1.13-1.26) compared with their urban counterparts. The rurality-associated risk of HF varied across race and sex and was greatest among Black men (HR, 1.34; 95% CI, 1.19-1.51), followed by White women (HR, 1.22; 95% CI, 1.07-1.39) and Black women (HR, 1.18; 95% CI, 1.08-1.28). Among White men, rurality was not associated with greater risk of incident HF (HR, 0.97; 95% CI, 0.81-1.16).

Conclusions and Relevance

Among predominantly low-income individuals in the southeastern United States, rurality was associated with an increased risk of HF among women and Black men, which persisted after adjustment for CV risk factors and SES. This inequity points to a need for additional emphasis on primary prevention of HF among rural populations.

Elucidating the Clinical Implications and Pathophysiology of Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction: A Call to Action: A Science Advisory From the American Heart Association

This science advisory focuses on the need to better understand the epidemiology, pathophysiology, and treatment of pulmonary hypertension in patients with heart failure with preserved ejection fraction. This clinical phenotype is important because it is common, is strongly associated with adverse outcomes, and lacks evidence-based therapies. Our goal is to clarify key knowledge gaps in pulmonary hypertension attributable to heart failure with preserved ejection fraction and to suggest specific, actionable scientific directions for addressing such gaps. Areas in need of additional investigation include refined disease definitions and interpretation of hemodynamics, as well as greater insights into noncardiac contributors to pulmonary hypertension risk, optimized animal models, and further molecular studies in patients with combined precapillary and postcapillary pulmonary hypertension. We highlight translational approaches that may provide important biological insight into pathophysiology and reveal new therapeutic targets. Last, we discuss the current and future landscape of potential therapies for patients with heart failure with preserved ejection fraction and pulmonary vascular dysfunction, including considerations of precision medicine, novel trial design, and device-based therapies, among other considerations. This science advisory provides a synthesis of important knowledge gaps, culminating in a collection of specific research priorities that we argue warrant investment from the scientific community.

A behavioural intervention to increase lay-people's intentions to initiate CPR in the event of Out-of-Hospital Cardiac Arrest: results from BICeP pilot trial

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council

Background

Cardiopulmonary resuscitation (CPR) is the single most important factor determining survival from out of hospital cardiac arrest (OHCA). Even when trained, most lay-people don’t attempt CPR when they encounter OHCA. Working closely with intended users and CPR experts we developed a theory-based text-messaging intervention designed to increase rates of CPR. This pilot study was conducted to evaluate the acceptability of the messages, explore participant responses to them and to trial measures for a full evaluation.

Design

A before-and-after study plus qualitative interviews

Methods

Twenty lay-people from across Scotland agreed to take part and to receive the intervention (35 text-messages over approx. 6 weeks) At baseline and after participants had received intervention (approx. 6 weeks later) we measured how likely people were to perform CPR (intention) in relation to 4 scenarios and self-assessed competence and confidence about performing CPR (self-efficacy) in general. We conducted qualitative interviews with 10 participants to elicit their views of the intervention

Results

Twenty lay-people (6F, 14M; aged 20-84) participated, all providing full baseline data. 19/20 participants received at least 20 messages. 15/20 provided follow-up data and ten were interviewed. Baseline intentions to initiate CPR in CPR scenarios were high (18.1) but still greater after the intervention (19.5). Increases in theory-based predictors of intention, self-efficacy (pre:74.5 post:81.0) and self-assessed competence (pre:19.5 post:20.5) were also observed following the intervention. Qualitative data suggested the intervention was positively received and viewed as helpful in improving confidence by reinforcing and building on messages from training. Interviewees suggested additional options for delivery format and pace would be helpful.

Conclusions

A behaviour-change text-message intervention delivered after CPR training is acceptable, easily scalable and may help improve rates of lay CPR initiation. Full scale evaluation of effectiveness is planned.

Relation of the Dietary Approaches to Stop Hypertension Dietary Pattern to Heart Failure Risk and Socioeconomic Status (from the Southern Community Cohort Study)

The Dietary Approaches to Stop Hypertension (DASH) dietary pattern has been associated with a lower risk of incident heart failure (HF); however, previous studies were conducted in mostly middle-income White populations. The association between DASH and incident HF risk in lower income and Black individuals is less well understood. We analyzed 25,300 White and Black adults without a history of HF at enrollment (2002 to 2009) in the Southern Community Cohort Study receiving Centers for Medicare and Medicaid Services. Alignment with DASH was assessed at enrollment using a validated food frequency questionnaire. Incident HF was ascertained from Centers for Medicare and Medicaid Services claims through 2016. The association between DASH diet alignment and incident HF was examined in multivariable-adjusted Cox proportional hazards regression models, including an interaction term testing effect modification by income. The cohort was predominantly middle-aged (median 54 years), Black (68%), female (63%), and low-income (88% <$25,000/year/household). Socioeconomic factors, including education and annual income, were larger contributors to the variance in DASH score than were cardiovascular co-morbidities. The association between DASH dietary alignment and HF risk was not significant overall (hazard ratio [HR] 1.00; 95% confidence interval [CI] 0.96 to 1.04) or in race-sex groups. However, the association between alignment with the DASH diet and HF risk significantly varied by income (interaction p = 0.030), with neutral and inverse associations in lower (<$25,000/year) and higher ($≥25,000) income participants, respectively. In conclusion, income modified the association between healthier dietary patterns and risk of incident HF. In lower income participants, greater alignment with the DASH diet was not associated with lower HF risk.

A national initiative to promote public involvement in medicine safety in Scotland: the use of a population survey to identify candidate behaviours for intervention development

Introduction

Medicines are the most commonly used healthcare intervention (1). Every medicine has benefits and harms. One of the five objectives of the WHO Global Patient Safety campaign, Medication Without Harm, is to “empower patients, families and their carers to become actively involved and engaged in treatment or care decisions, ask questions, spot errors and effectively manage their medications” (2). Effective strategies are needed to promote greater public involvement in the safe and effective use of medicines.

Aim

The aim of this study was to explore the prevalence of public behaviour in terms of information-/advice-seeking about medicines in general, newly prescribed medicines, and pain management including their use of oral, over-the-counter (OTC) analgesics. The survey also included exploration of self-reported behaviour regarding their use of pharmacies and OTC analgesics.

Methods

A cross-sectional online survey of 1000 adults (aged &gt;16years) in Scotland was undertaken in collaboration with Ipsos MORI. The content was informed by a multi-stakeholder prioritisation event (held in November 2019) and supplemented with information from earlier studies, including national surveys using Citizen Panels. The following themes were included in the questionnaire:

The data were input online by respondents then cleaned and weighted by Ipsos Mori using random iterative method (RIM) weighting to the known offline population proportions for age, gender, region and working status. All data were analysed and presented using descriptive statistics.

Results

Most respondents (78%, n=777) had used a pharmacy in the previous 12 months to obtain a prescription medicine and slightly fewer (61%, n=610) to obtain an OTC medicine. Low levels of information- and advice-seeking were reported especially on receipt of new prescription medicines.

Few (5%) respondents ‘always’ discussed their new prescription medicine with pharmacy staff and 29% reported ‘never’ engaging in this behaviour. Older people (&gt; 35 years) were less likely to engage in this behaviour. Up to 65% of respondents reported ‘always’ engaging with specific aspects of the appropriate use of OTC analgesics e.g. appropriate dose.

Potentially unsafe behaviours were identified with medicine disposal. Nearly one third (29%) of respondents considered waste bin disposal to be of low or no harm, and 19% considered disposal of medicines via the toilet/sink to be of low/no harm.

Conclusion

Despite the extensive use of pharmacies, low levels of information-/advice-seeking were reported especially on receipt of new prescription medicines. Potentially unsafe behaviours were also identified with medicine use and disposal. The key determinants of these behaviours will be explored in more detail and theory-based interventions will be developed and tested to evaluate their effect.

Respondent opinion (positively or negatively) regarding their perceptions regarding community pharmacies and/or pharmacy personnel could have been influenced by the increased use and/or awareness of community pharmacy services due to the pandemic.

References

(1) National Institute for Health and Care Excellence. Medicines optimisation: the safe and effective use of medicines to enable the best possible outcomes. NICE Guidelines [NG5]. 2015. https://www.nice.org.uk/guidance/ng5 (accessed 13/10/2021).

(2) Medication without harm - Global patient safety challenge on medication safety. Geneva: World Health Organization, 2017. Licence: CCBY-NC-SA3.0IGO.

Cardiovascular magnetic resonance evaluation of soldiers after recovery from symptomatic SARS-CoV-2 infection: a case-control study of cardiovascular post-acute sequelae of SARS-CoV-2 infection (CV PASC)

BACKGROUND

Myocarditis is a potential complication after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and a known cause of sudden cardiac death. Given the athletic demands of soldiers, identification of myocarditis and characterization of post-acute sequelae of SARS-CoV-2 infection with cardiovascular symptoms (CV PASC) may be critical to guide return-to-service. This study sought to evaluate the spectrum of cardiac involvement among soldiers with cardiopulmonary symptoms in the late convalescent phase of recovery from SARS-CoV-2 compared to a healthy soldier control group, and to determine the rate of progression to CV PASC.

METHODS

All soldiers referred for cardiovascular magnetic resonance (CMR) imaging for cardiopulmonary symptoms following COVID-19 were enrolled and matched by age, gender, and athletic phenotype 1:1 to soldiers undergoing CMR in the year prior to the first case of COVID-19 at our institution. Demographic, clinical, laboratory, and imaging parameters were compared between groups. The diagnosis of acute myocarditis was made using modified Lake Louise criteria. Wilcoxon rank sum and chi-squared tests were used for comparison of continuous and categorical variables, respectively.

RESULTS

Fifty soldier cases and 50 healthy soldier controls were included. The median time from SARS-CoV-2 detection to CMR was 71 days. The majority of cases experienced moderate symptoms (N = 43, 86%), while only 10% required hospitalization. The right ventricular (RV) ejection fraction (RVEF) was reduced in soldier cases compared to controls (51.0% vs. 53.2%, p = 0.012). Four cases were diagnosed with myocarditis (8%), 1 (2%) was diagnosed with Takotsubo cardiomyopathy, and 1 (2%) had new biventricular systolic dysfunction of unclear etiology. Isolated inferior RV septal insertion late gadolinium enhancement (LGE) was present in 8 cases and 8 controls (16% vs. 24%, p = 0.09). Seven of the 19 (37%) cases that completed an intermediate-term follow-up survey reported CV PASC at a median of 139 days of follow-up. Two of the 7 soldiers (29%) with CV PASC had a pathological clinical diagnosis (myocarditis) on CMR.

CONCLUSIONS

Cardiovascular pathology was diagnosed in 6 symptomatic soldiers (12%) after recovery from SARS-CoV-2, with myocarditis found in 4 (8%). RVEF was reduced in soldier cases compared to controls. CV PASC occurred in over one-third of soldiers surveyed, but did not occur in any soldiers with asymptomatic acute SARS-CoV-2 infection.

The psychological and behavioural factors associated with laypeople initiating CPR for out-of-hospital cardiac arrest: a systematic review

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Chief Scientist Office, Scottish Government

OnBehalf

BICeP Study Group

Background

Prompt, effective CPR greatly increases the chances of survival in out-of-hospital cardiac arrest. However, it is often not provided, even by people who have previously undertaken training. Psychological and behavioural factors are likely to be important in relation to CPR initiation by lay-people but have not yet been systematically identified.

Objective

To identify the psychological and behavioural factors associated with CPR initiation amongst lay-people. 

Methods  

Data sources

Cochrane Library, MEDLINE, EMBASE, CINAHL, PsycInfo and Google Scholar. 

Study eligibility criteria

Primary studies reporting psychological or behavioural factors and data on CPR initiation involving lay-people published (inception to 15th January 2020).

Study appraisal and synthesis methods

Potential studies were screened and quality assessed independently by two reviewers. Study characteristics, psychological and behavioural factors associated with CPR initiation were extracted from included studies, categorised by study type and synthesised narratively. 

Results

Ninety studies (132,429 participants) comprising various designs, populations and of mostly weak quality were identified. The strongest and most ecologically valid studies identified factors associated with CPR initiation: the overwhelming emotion of the situation, perceptions of capability, uncertainty about when CPR is appropriate, feeling unprepared  and fear of doing harm. Current evidence is limited by a preponderance of atheoretical cross-sectional surveys using unvalidated measures with relatively little formal testing of posited ‘predictors’.

Conclusions

We will present the psychological and behavioural factors that are likely useful foci for future interventions aiming to increase CPR initiation. The literature in this area would benefit from more robust study designs which make greater use of theory.

Developing a behavioural intervention to increase lay-people"s intentions to initiate CPR in the event of Out-of-Hospital Cardiac Arrest (OHCA)

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council

OnBehalf

BICeP Study Group

Background

Prompt, effective bystander cardiopulmonary resuscitation (CPR) is the single most important factor determining survival from out of hospital cardiac arrest (OHCA), increasing survival up to 4-fold. However only 35%-45% of people trained in CPR actually attempt it when required. This study uses psychological theory and behaviour change techniques (BCTs) to increase the proportion of bystanders who attempt CPR in a real emergency.

Design

Intervention development study

Methods

Intervention content was informed by two recent systematic reviews, which identified barriers to bystander CPR and BCTs within existing training programmes (PROSPERO CRD42018117438; CRD42019126745) and a qualitative study exploring participants’ views (n = 12) of draft text messages. A lay bystander user-involvement panel (n = 7) and an expert advisory group (comprising representatives from CPR training organisations) worked with the research team to co-produce the final intervention and agree the schedule for text message delivery.  BCT content was assessed by two independent experts. A framework analysis of interviews was undertaken. 

Results

Recognising and addressing fears, and helping people to better prepare for real-life situations were identified to be important to participants. Short, simple texts from a credible source and with a positive tone were strongly preferred, there was a strong aversion to anything "guilt-inducing". Pictures and personalisation were important, rewards less so. Regarding frequency: participants varied but around 1/week was considered adequate by most. A total of n = 35 text-messages with verified BCT content were co-developed with participants.

Conclusions

A text message intervention incorporating BCTs, which is acceptable to intended users and CPR trained individuals has been produced and will be subject to future evaluation.

Pre-Flight Calibration of the Mars 2020 Rover Mastcam Zoom (Mastcam-Z) Multispectral, Stereoscopic Imager

The NASA Perseverance rover Mast Camera Zoom (Mastcam-Z) system is a pair of zoomable, focusable, multi-spectral, and color charge-coupled device (CCD) cameras mounted on top of a 1.7 m Remote Sensing Mast, along with associated electronics and two calibration targets. The cameras contain identical optical assemblies that can range in focal length from 26 mm ( 25.5 ∘ × 19.1 ∘ FOV ) to 110 mm ( 6.2 ∘ × 4.2 ∘ FOV ) and will acquire data at pixel scales of 148-540 μm at a range of 2 m and 7.4-27 cm at 1 km. The cameras are mounted on the rover's mast with a stereo baseline of 24.3 ± 0.1  cm and a toe-in angle of 1.17 ± 0.03 ∘ (per camera). Each camera uses a Kodak KAI-2020 CCD with 1600 × 1200 active pixels and an 8 position filter wheel that contains an IR-cutoff filter for color imaging through the detectors' Bayer-pattern filters, a neutral density (ND) solar filter for imaging the sun, and 6 narrow-band geology filters (16 total filters). An associated Digital Electronics Assembly provides command data interfaces to the rover, 11-to-8 bit companding, and JPEG compression capabilities. Herein, we describe pre-flight calibration of the Mastcam-Z instrument and characterize its radiometric and geometric behavior. Between April 26 t h and May 9 t h , 2019, ∼45,000 images were acquired during stand-alone calibration at Malin Space Science Systems (MSSS) in San Diego, CA. Additional data were acquired during Assembly Test and Launch Operations (ATLO) at the Jet Propulsion Laboratory and Kennedy Space Center. Results of the radiometric calibration validate a 5% absolute radiometric accuracy when using camera state parameters investigated during testing. When observing using camera state parameters not interrogated during calibration (e.g., non-canonical zoom positions), we conservatively estimate the absolute uncertainty to be < 10 % . Image quality, measured via the amplitude of the Modulation Transfer Function (MTF) at Nyquist sampling (0.35 line pairs per pixel), shows MTF Nyquist = 0.26 - 0.50 across all zoom, focus, and filter positions, exceeding the > 0.2 design requirement. We discuss lessons learned from calibration and suggest tactical strategies that will optimize the quality of science data acquired during operation at Mars. While most results matched expectations, some surprises were discovered, such as a strong wavelength and temperature dependence on the radiometric coefficients and a scene-dependent dynamic component to the zero-exposure bias frames. Calibration results and derived accuracies were validated using a Geoboard target consisting of well-characterized geologic samples.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11214-021-00795-x.

Race and Sex Differences in Modifiable Risk Factors and Incident Heart Failure

OBJECTIVES

The purpose of this study was to examine race- and sex-based variation in the associations between modifiable risk factors and incident heart failure (HF) among the SCCS (Southern Community Cohort Study) participants.

BACKGROUND

Low-income individuals in the southeastern United States have high HF incidence rates, but relative contributions of risk factors to HF are understudied in this population.

METHODS

We studied 27,078 black or white SCCS participants (mean age: 56 years, 69% black, 63% women) enrolled between 2002 and 2009, without prevalent HF, receiving Centers for Medicare and Medicaid Services. The presence of hypertension, diabetes mellitus, physical underactivity, high body mass index, smoking, high cholesterol, and poor diet was assessed at enrollment. Incident HF was ascertained using International Classification of Diseases-9th revision, codes 428.x in Centers for Medicare and Medicaid Services data through December 31, 2010. Individual risk and population attributable risk for HF for each risk factor were quantified using multivariable Cox models.

RESULTS

During a median (25th, 75th percentile) 5.2 (3.1, 6.7) years, 4,341 (16%) participants developed HF. Hypertension and diabetes were associated with greatest HF risk, whereas hypertension contributed the greatest population attributable risk, 31.8% (95% confidence interval: 27.3 to 36.0). In black participants, only hypertension and diabetes associated with HF risk; in white participants, smoking and high body mass index also associated with HF risk. Physical underactivity was a risk factor only in white women.

CONCLUSIONS

In this high-risk, low-income cohort, contributions of risk factors to HF varied, particularly by race. To reduce the population burden of HF, interventions tailored for specific race and sex groups may be warranted.

Patterns of periodontal disease progression based on linear mixed models of clinical attachment loss

AIM

The goal of the present longitudinal cohort study was to examine patterns of periodontal disease progression at progressing sites and subjects defined based on linear mixed models (LMM) of clinical attachment loss (CAL).

MATERIALS AND METHODS

A total of 113 periodontally healthy and 302 periodontitis subjects had their CAL calculated bimonthly for 12 months. LMMs were fitted for each site and the predicted CAL levels used to categorize their progression state. Participants were grouped based on the number of progressing sites into unchanged, transitional and active subjects. Patterns of periodontal disease progression were explored using descriptive statistics.

RESULTS

Progression occurred primarily at molars (50% of progressing sites) and inter-proximal sites (72%), affected a higher proportion of deep than shallow sites (2.7% versus 0.7%), and pocketing was the main mode of progression (49%). We found a low level of agreement (47%) between the LMM and traditional approaches to determine progression such as change in CAL ≥3 mm. Fourteen per cent of subjects were classified as active and among those 93% had periodontitis. The annual mean rate of progression for the active subjects was 0.35 mm/year.

CONCLUSION

Progressing sites and subjects defined based on LMMs presented patterns of disease progression similar to those previously reported in the literature.

Immunohistochemical Characterization of Sarcomas in Trp53+/- Haploinsufficient Mice

The use of immunohistochemical (IHC) staining in determining and/or confirming the cellular origin of poorly differentiated sarcomas was evaluated in this study. Sarcomatous neoplasms were evaluated in a research study conducted in 2 strains of p53+/- haploinsufficient mice. The most common neoplasms were undifferentiated sarcomas, followed by osteosarcomas and rhabdomyosarcomas (RMSs). The RMSs were poorly differentiated and appeared similar to the pleomorphic, or adult type, RMS of humans. All sarcomas stained positive by IHC for the mesenchymal cell intermediate filament vimentin. The RMSs were identified by positive IHC staining for myogenin, a transcription factor specific to skeletal muscle. Osteosarcomas were easily identifiable on hematoxylin and eosin-stained slides; no generally accepted IHC stain specific for bone is presently available. Some of the undifferentiated sarcomas contained numerous macrophages that stained positive for F4/80, a macrophage marker; the positive-staining cells were considered to be infiltrating macrophages. One-third of the neoplasms observed in this study were associated with subcutaneous implanted electronic microchips used for animal identification. Based upon histopathologic evaluation and IHC staining, it was not possible to distinguish neoplasms associated with subcutaneous microchips from neoplasms not associated with microchips.

RV Contractile Function and its Coupling to Pulmonary Circulation in Heart Failure With Preserved Ejection Fraction: Stratification of Clinical Phenotypes and Outcomes

OBJECTIVES

This study sought to investigate how right ventricular (RV) contractile function and its coupling with pulmonary circulation (PC) stratify clinical phenotypes and outcome in heart failure preserved ejection fraction (HFpEF) patients.

BACKGROUND

Pulmonary hypertension and RV dysfunction are key hemodynamic abnormalities in HFpEF.

METHODS

Three hundred eighty seven HFpEF patients (mean age 64 ± 12 years, 59% females, left ventricular ejection fraction 59 ± 7%) underwent RV and pulmonary hemodynamic evaluation by echocardiography (entire population) and right heart catheterization (219 patients). Patients were investigated by tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) relationship and stratified according to TAPSE/PASP ratio tertiles (1: <0.35; 2: 0.35 to 0.57; 3: >0.57). Specifically, TAPSE/PASP ratio was taken as a noninvasive index of RV to PC coupling based on the correlation with invasively evaluated RV systolic elastance/arterial elastance (r = 0.35; p < 0.0001).

RESULTS

Groups had similar prevalence of comorbidities except for a higher prevalence of atrial fibrillation and kidney dysfunction in tertile 1. Progressively increasing levels of natriuretic peptides, worse systemic and pulmonary hemodynamics, abnormal exercise aerobic capacity and ventilatory inefficiency were observed from the highest to lowest TAPSE/PASP tertile. TASPE/PASP correlated with pulmonary artery compliance (r = 0.69; p < 0.0001). Remarkably, the tertile 1 group distributed along the worse portion of the curve at lower pulmonary artery compliance and higher pulmonary vascular resistances. In addition, the TAPSE/PASP ratio emerged as an independent predictor of worse outcomes.

CONCLUSIONS

A thorough assessment of RV-PC coupling and RV contractile function stratify HFpEF phenotypes at different level of risk. These observations shift the interest toward therapeutic strategies that may benefit the right heart as primary unmet need in the complex pathophysiology of the HFpEF syndrome.

Tumor-Promoting, Initiating, and Hepatotoxic Effects of 3,4,3',4'-Tetrabromobiphenyl (34-TBB) in Rats

Female, 180–200 g Sprague-Dawley rats were used to determine if 3,4,3',4'-tetrabromobi-phenyl (34-TBB) is a promoter or initiator in a two-stage hepatocarcinogenesis assay. To test for promotion, rats were partially hepatectomized (PH) 24 hr before initiation (day 1) with 10 mg of diethylnitrosamine (DEN)/kg body weight given intraperitoneally (IP). Thirty days later, promotion was with 34-TBB (0.1,1 or 5 mg/kg) or phenobarbital (PB) (500 mg/kg) in diets for 180 days. To test for initiation, rats were PH and were initiated on day 1 with 34-TBB (1, 5, or 10 mg/kg) orally or DEN (10 mg/kg) IP. On day 31, promotion was with 500 mg of PB/kg of diet for 180 days. Noninitiated and non-PH rats were used to assess the histological and ultrastructural tissue changes associated with administration of 34-TBB in the diet for 180 days. Tumor promotion-initiation were assessed by counting and measuring hepatic enzyme-altered foci (EAF) with gamma-glutamyl transpeptidase (GGT) activity. Congener 34-TBB acts as a promoter in experimental hepatocarcinogenesis in rats, as evidenced by increased numbers of GGT-positive EAF. Also, 34-TBB may have initiation potential, as suggested by increased numbers of EAF in rats initiated with 34-TBB and promoted by PB. Dietary administration of 34-TBB for 180 days is not severely toxic in rats, as evidenced by mild histological and ultrastructural changes and minimal alterations in organ and body weights. Congener 34-TBB does not accumulate in liver and adipose tissue of rats.

Predicting the Performance of Chemical Blowing Agents Using Thermal Analysis Techniques

This paper demonstrates how the cell morphology of extruded expanded poly-propylene (EPP) may be related to the thermal decomposition behavior of chemical blowing agents (CBAs) used in their production. The thermal analysis techniques used in this study were differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Tests were completed on six of the CBAs now available for use with PP. It was found that agents with a higher decomposition temperature and rate of gas evolution generally produced foam samples with a smaller cell size and higher cell density. This information will be beneficial to producers and users of CBAs.

Prognostic Utility and Clinical Significance of Cardiac Mechanics in Heart Failure With Preserved Ejection Fraction: Importance of Left Atrial Strain

BACKGROUND

Left atrial (LA) enlargement is associated with adverse events in heart failure with preserved ejection fraction (HFpEF). However, the role of LA mechanics (ie, LA strain measures) in HFpEF has not been well studied. We hypothesized that in HFpEF, reduced (worse) LA strain is a key pathophysiologic abnormality and is a stronger correlate of adverse events than left ventricular or right ventricular longitudinal strain.

METHODS AND RESULTS

We evaluated baseline LA function in 308 patients with HFpEF who were followed up longitudinally for adverse outcomes. All patients underwent speckle-tracking echocardiography for measurement of left ventricular longitudinal strain, right ventricular free wall strain, and LA booster, conduit, and reservoir strains. The clinical and prognostic significance of left ventricular, right ventricular, and LA strain measures was assessed by regression analyses. The mean age was 65±13 years, 64% were women, 26% had atrial fibrillation, and LA enlargement was present in the majority of patients (67%). Decreased LA reservoir strain was associated with increased pulmonary vascular resistance (P<0.0001) and decreased peak oxygen consumption (P=0.0001). Of the left ventricular, right ventricular, and LA strain measures, LA reservoir strain was the strongest correlate of adverse events and was independently associated with the composite outcome of cardiovascular hospitalization or death (adjusted hazard ratio per 1-SD decrease in LA strain, 1.54; 95% CI, 1.15-2.07; P=0.006).

CONCLUSIONS

Abnormal indices of LA mechanics (particularly LA reservoir strain) are powerful clinical and prognostic factors in HFpEF. Unloading the LA and augmentation of LA function may be important future therapeutic targets in HFpEF.

REGISTRATION INFORMATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01030991.

Pseudomonas aeruginosa Induced Airway Epithelial Injury Drives Fibroblast Activation: A Mechanism in Chronic Lung Allograft Dysfunction

Bacterial infections after lung transplantation cause airway epithelial injury and are associated with an increased risk of developing bronchiolitis obliterans syndrome. The damaged epithelium is a source of alarmins that activate the innate immune system, yet their ability to activate fibroblasts in the development of bronchiolitis obliterans syndrome has not been evaluated. Two epithelial alarmins were measured longitudinally in bronchoalveolar lavages from lung transplant recipients who developed bronchiolitis obliterans syndrome and were compared to stable controls. In addition, conditioned media from human airway epithelial cells infected with Pseudomonas aeruginosa was applied to lung fibroblasts and inflammatory responses were determined. Interleukin-1 alpha (IL-1α) was increased in bronchoalveolar lavage of lung transplant recipients growing P. aeruginosa (11.5 [5.4-21.8] vs. 2.8 [0.9-9.4] pg/mL, p < 0.01) and was significantly elevated within 3 months of developing bronchiolitis obliterans syndrome (8.3 [1.4-25.1] vs. 3.6 [0.6-17.1] pg/mL, p < 0.01), whereas high mobility group protein B1 remained unchanged. IL-1α positively correlated with elevated bronchoalveolar lavage IL-8 levels (r(2)  = 0.6095, p < 0.0001) and neutrophil percentage (r(2)  = 0.25, p = 0.01). Conditioned media from P. aeruginosa infected epithelial cells induced a potent pro-inflammatory phenotype in fibroblasts via an IL-1α/IL-1R-dependent signaling pathway. In conclusion, we propose that IL-1α may be a novel therapeutic target to limit Pseudomonas associated allograft injury after lung transplantation.

Modelling changes in clinical attachment loss to classify periodontal disease progression

AIM

The goal of this study was to identify progressing periodontal sites by applying linear mixed models (LMM) to longitudinal measurements of clinical attachment loss (CAL).

METHODS

Ninety-three periodontally healthy and 236 periodontitis subjects had their CAL measured bi-monthly for 12 months. The proportions of sites demonstrating increases in CAL from baseline above specified thresholds were calculated for each visit. The proportions of sites reversing from the progressing state were also computed. LMM were fitted for each tooth site and the predicted CAL levels used to categorize sites regarding progression or regression. The threshold for progression was established based on the model-estimated error in predictions.

RESULTS

Over 12 months, 21.2%, 2.8% and 0.3% of sites progressed, according to thresholds of 1, 2 and 3 mm of CAL increase. However, on average, 42.0%, 64.4% and 77.7% of progressing sites for the different thresholds reversed in subsequent visits. Conversely, 97.1%, 76.9% and 23.1% of sites classified as progressing using LMM had observed CAL increases above 1, 2 and 3 mm after 12 months, whereas mean rates of reversal were 10.6%, 30.2% and 53.0% respectively.

CONCLUSION

LMM accounted for several sources of error in longitudinal CAL measurement, providing an improved method for classifying progressing sites.

233 ANTI-MÜLLERIAN HORMONE AS A PREDICTIVE ENDOCRINE MARKER FOR SUPEROVULATORY RESPONSE AND EMBRYO PRODUCTION IN BEEF CATTLE

A study investigated the use of anti-Müllerian hormone (AMH) and/or follicle counts as a predictor of subsequent superovulatory response and embryo production in 79 beef cows. Before initiation of superovulation, ultrasonography was used to scan the ovaries of each donor cow to record the number of 3 to 5 mm follicles present, and a blood sample was collected for measure of serum AMH. At the time of embryo collection, the ovaries of donor cows were palpated to estimate the number of corpora lutea (CL) present on each ovary. Recovered embryos were evaluated for stage of development and morphological quality. Across cows, serum AMH ranged from 0.013 to 0.898 ng mL–1, with a mean of 0.293 ng mL–1. The distribution of AMH concentrations was divided into quartiles (AMH Q1 through Q4, with Q1 the lowest and Q4 the highest, ng mL–1) for analysis (ANOVA). Number of donors/collections in AMH Q1 through Q4 was 26, 22, 24, and 24, respectively. Donor cows in AMH Q4 had a greater (P < 0.001) number of 3- to 5-mm follicles at the start of superovulation than did donors in either Q1 or Q2. At embryo collection, cows in AMH Q3 and 4 had more (P < 0.001) palpable CL than cows in AMH Q1. The mean number of embryos recovered from donor cows in AMH Q4 (20.1 ± 1.8) was greater (P < 0.001) than those recovered from cows in either AMH Q1 (9.8 ± 1.8) or 2 (9.4 ± 1.9), but similar to that of AMH Q3 (15.5 ± 1.8). Percentages of recovered embryos classified as transferrable, degenerate, or unfertilized were similar (P ≥ 0.275) across AMH quartiles. Analysis indicated that AMH was positively correlated (P < 0.001) with mean follicles (r = 0.458), CL (r = 0.452), and embryos recovered (r = 0.430). To determine if follicle counts at the start of superovulation are predictive of superovulatory response, the distribution of follicle counts was divided into quartiles (F Q1 through Q4, with Q1 the lowest and Q4 the highest) for analysis. Donor cows with higher follicle counts (F Q3 and 4) at the start of superovulation had more (P < 0.001) palpable CL at embryo collection than donor cows in F Q1 or 2. More (P < 0.001) embryos (20.0 ± 2.2 v. 9.6 ± 1.8 and 11.6 ± 1.6) were recovered from cows with the highest follicle counts (F Q4) compared with cows having lower (F Q1 and 2) follicle counts, respectively. The percentage of transferable embryos and unfertilized ova were similar (P ≥ 0.688) across follicle count quartiles. As was noted for AMH, mean number of follicles at the start of superovulation was positively correlated (P < 0.001) with mean CL (r = 0.556) and mean embryos (r = 0.423) but not percentages of viable or degenerate embryos or unfertilized oocytes (P ≥ 0.153). Results confirm that relative AMH concentration was positively correlated with number of small antral follicles in the ovaries of cows and might be used to either predict superovulatory response or possibly adjust superovulatory regimen to improve superovulatory response. Further study is needed to determine the effectiveness of using either AMH concentration or follicle counts to adjust superovulatory regimens.

Sex differences on the acute effects of caffeine on maximal strength and muscular endurance

The aim of this study was to look at the effects of caffeine on strength performance and to examine any differences between sexes. Sixteen moderately active, resistance-trained individuals (10 males and 8 females) performed 2 trials (excluding a familiarisation trial). The effect of 5 mg/kg body mass (BM) caffeine or a placebo on bench press (BP) one repetition maximum (1RM), squat 1RM, the number of BP reps to failure at 40% 1RM (total weight lifted; TWL), pain rating (0-10) were recorded after each final successful lift. BP 1RM was significantly greater (P=0.016), with an increase of 5.91% for males and an increase of 10.69% for females. However, there was no sex difference in squat 1RM with males producing 130.3±27.8 and 134.0±28.9 kg and females producing 66.9±6.2 and 65.3±7.0 kg for placebo and caffeine, respectively. TWL tended to increase with caffeine for males from 1,246.8±704.9 to 1,545.5±920.3 kg; with females having no effect of caffeine (397.8±245.1 to 398.8±182.7kg; P=0.06). Caffeine had no effect on pain perception. This study found that 5 mg/kg BM caffeine improved BP 1RM in resistance-trained males and females. However, for TWL there was a tendency towards improvement in males only, suggesting a sex difference to caffeine ingestion for TWL.

Differential roles of microglia and monocytes in the inflamed central nervous system

Phagocytic monocyte-derived macrophages associate with the nodes of Ranvier and initiate demyelination while microglia clear debris and display a suppressed metabolic gene signature in EAE.

In the human disorder multiple sclerosis (MS) and in the model experimental autoimmune encephalomyelitis (EAE), macrophages predominate in demyelinated areas and their numbers correlate to tissue damage. Macrophages may be derived from infiltrating monocytes or resident microglia, yet are indistinguishable by light microscopy and surface phenotype. It is axiomatic that T cell–mediated macrophage activation is critical for inflammatory demyelination in EAE, yet the precise details by which tissue injury takes place remain poorly understood. In the present study, we addressed the cellular basis of autoimmune demyelination by discriminating microglial versus monocyte origins of effector macrophages. Using serial block-face scanning electron microscopy (SBF-SEM), we show that monocyte-derived macrophages associate with nodes of Ranvier and initiate demyelination, whereas microglia appear to clear debris. Gene expression profiles confirm that monocyte-derived macrophages are highly phagocytic and inflammatory, whereas those arising from microglia demonstrate an unexpected signature of globally suppressed cellular metabolism at disease onset. Distinguishing tissue-resident macrophages from infiltrating monocytes will point toward new strategies to treat disease and promote repair in diverse inflammatory pathologies in varied organs.

Serotonin-norepinephrine reuptake inhibitor therapy in late-life depression is associated with increased marker of bone resorption

Antidepressants are associated with bone loss and fractures in older adults. We treated depressed older adults with an antidepressant and examined its effects on bone turnover by comparing blood samples before and after treatment. Bone resorption increased after antidepressant treatment, which may increase fracture risk.

INTRODUCTION

Antidepressants have been associated with increased bone loss and fractures in older adults in observational studies, but the mechanism is unclear. We examined the effects of a serotonin-norepinephrine reuptake inhibitor, venlafaxine, on biomarkers of bone turnover in a prospective treatment study of late-life depression.

METHODS

Seventy-six individuals aged 60 years and older with current major depressive disorder received a 12-week course of venlafaxine XR 150-300 mg daily. We measured serum C-terminal cross-linking telopeptide of type I collagen (β-CTX) and N-terminal propeptide of type I procollagen (P1NP), measures of bone resorption and formation, respectively, before and after treatment. We then analyzed the change in β-CTX and P1NP within each participant. Venlafaxine levels were measured at the end of the study. We assessed depression severity at baseline and remission status after treatment.

RESULTS

After 12 weeks of venlafaxine, β-CTX increased significantly, whereas P1NP did not significantly change. The increase in β-CTX was significant only in participants whose depression did not remit (increase by 10 % in non-remitters vs. 4 % in remitters). Change in β-CTX was not correlated with serum levels of venlafaxine or norvenlafaxine.

CONCLUSION

Our findings suggest that the primary effect of serotonergic antidepressants is to increase bone resorption. However, such an increase in bone resorption seemed to depend on whether or not participants' depression remitted. Our results are in agreement with prior observational studies reporting increased bone loss in older adults taking serotonergic antidepressants. These negative effects on bone homeostasis could potentially contribute to increased fracture risk in older adults.

Pre-operative expectation predicts 12-month post-operative outcome among patients undergoing primary total hip replacement in European orthopaedic centres

OBJECTIVE

Patients' expectations of surgery may be related to outcomes of joint replacement. The aims of this study were to: (1). Identify patient characteristics associated with pre-operative expectations of total hip replacement (THR); (2). Explore whether pre-operative expectations predict surgical outcomes 12-months post-THR.

METHOD

The European collaborative database of cost and practice patterns of THR (EUROHIP) study consists of 1327 consenting patients coming to primary THR for osteoarthritis (OA) across 20 European orthopaedic centres. Ordered logistic regression modelling was used to look at the association between patients pre-operative expectations and baseline characteristics (age, sex, education, American Society of Anaesthesiologists (ASA) status, Kellgren & Lawrence (K&L) grade, body mass index (BMI), medication use, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) score, EQ5D (EuroQol) score). The Outcome Measures in Rheumatology (OMERACT)/Osteoarthritis Research Society International (OARSI) responder criteria were used to classify patients as improved/not improved 12-months post-THR. Logistic regression modelling was used to explore whether pre-operative expectations predict response to THR.

RESULTS

Greater numbers of pre-operative expectations were associated with younger age, women, increasing BMI, and more education. The more pre-operative expectations a patient had, the more likely they were to improve after surgery. Each individual expectation a patient had, was associated with a 34% increase in improvement [95% confidential interval (CI) 1%-78%]. Analyses within dimensions of the WOMAC suggest the association is strongest for stiffness and function.

CONCLUSION

There is large variation in patients' pre-operative expectations of THR. Greater numbers of pre-operative expectations were associated with improvement following THR. This appears to be driven more by stiffness and function. These findings have implications for informed patient-clinician decision-making.

Social support and regular physical activity: does planning mediate this link?

OBJECTIVES

Social support for physical activity is reliably associated with regular physical activity, however the social cognitive processes, particularly post-intentional processes, that can explain this link have not been well characterized. In this study, we examined the extent to which the relationship between social support for physical activity and subsequent physical activity can be accounted for by planning processes.

DESIGN AND METHOD

The design was prospective observational and the sample consisted of 903 university students. Participants completed standard theory of planned behaviour, planning, and physical activity measures at 2 time points, approximately 7 weeks apart. A gender stratified multiple mediation model was conducted to test the study hypotheses.

RESULTS

A significant interaction between social support and gender was observed. This indicated that lower levels of social support for physical activity were associated with lower levels of physical activity at Time 2, for women only. In multiple mediation analysis, this was partly explained by the indirect effects of social support through perceived behavioural control and coping planning.

CONCLUSION

These findings highlight the importance of interpersonal processes in understanding the post-intentional social cognitive determinants of regular physical activity. It is likely that planning processes relating to physical activity are often influenced by those in the ongoing immediate social environment who support this behaviour. Future development of theory and interventions should take account of the socially interactive nature of planning processes.

Alveolar bone measurement precision for phosphor-plate images

OBJECTIVES

The aim was to demonstrate methods for determining measurement precision and to determine the precision of alveolar bone measurements made with a vacuum-coupled positioning device and phosphor plate images.

STUDY DESIGN

Subjects were rigidly attached to the x-ray tube by means of a vacuum coupling device and custom cross-arch bite plates. Original and repeat radiographs (taken within minutes of each other) were obtained of the mandibular posterior teeth of 51 subjects, and cementoenamel junction-alveolar crest (CEJ-AC) distances were measured on both sets of images. In addition, x-ray transmission (radiodensity) and AC height differences were determined by subtracting one image from the other. Image subtractions and measurements were performed twice. Based on duplicate measurements, the root mean square standard deviation (precision) and least significant change (LSC) were calculated. LSC is the magnitude of change in a measurement needed to indicate that a true biologic change has occurred.

RESULTS

The LSCs were 4% for x-ray transmission, 0.49 mm for CEJ-AC distance, and 0.06 mm for crest height.

CONCLUSION

The LSCs for our CEJ-AC and x-ray transmission measurements were similar to what has been previously reported. The LSC for AC height (determined with image subtraction) was <0.1 mm. Compared with findings from earlier studies, this represents a highly precise measurement of AC height. The methods demonstrated for calculating LSC can be used by investigators to determine how large changes in radiographic measurements need to be before the changes can be considered to be (with 95% confidence) true biologic changes and not noise (i.e., equipment/observer error).

Characterization of uterine granular cell tumors in B6C3F1 mice: a histomorphologic, immunohistochemical, and ultrastructural study

The granular cell tumor is most often a benign neoplasm of uncertain origin. Four uterine granular cell tumors in control and treated female B6C3F1 mice were identified in chronic studies at the National Toxicology Program. Two tumors occurred in untreated control animals and 2 in treated animals receiving different compounds. Tissue sections were evaluated histologically and stained with hematoxylin and eosin, periodic acid-Schiff with diastase resistance, Masson's trichrome, toluidine blue, phosphotungstic acid-hematoxylin, and stained immunohistochemically with a panel of antibodies to muscle (desmin, alpha smooth muscle actin), neural (S-100, neuron specific enolase), epithelial (wide-spectrum cytokeratin), and macrophage (F4/80) markers. The main histomorphologic feature of tumor cells was the presence of abundant cytoplasmic eosinophilic granules that stained positive for periodic acid-Schiff with diastase resistance. Tumors varied in appearance and were comprised of sheets and nests of round to polygonal cells with distinct borders. Nuclei were hyperchromatic, pleomorphic, and centrally to eccentrically located and often contained single nucleoli. Occasional multinucleated giant cells were observed. Tumors were pale pink and homogeneous with trichrome stain and negative with toluidine blue. Three tumors had positive to weakly positive immunoreactivity for desmin, and 1 was positive for alpha smooth muscle actin. Expression of S-100, wide-spectrum cytokeratin, and neuron-specific enolase was negative for all tumors. Ultrastructurally, prominent electron-dense cytoplasmic granules were abundant and contained secondary lysosomes with heterogeneous lysosomal contents. The characteristics of these uterine granular cell tumors were suggestive of a myogenic origin.

A low concentration of genistein induces estrogen receptor-alpha and insulin-like growth factor-I receptor interactions and proliferation in uterine leiomyoma cells

BACKGROUND

Previously, we found that genistein at low concentrations stimulates the growth of human uterine leiomyoma (LM) cells, but not uterine smooth muscle (myometrial) cells (SMC). The aim of this study was to understand the molecular mechanism whereby genistein causes hyperproliferation of LM cells.

METHODS

The effects of genistein at 1 microg/ml on LM cells and SMC were evaluated using estrogen response element gene reporter, real-time RT-PCR, western blot, immunoprecipitation and cell proliferation assays.

RESULTS

Elevated estrogen receptor (ER) transactivation, increased mRNA expression of early estrogen-responsive genes, progesterone receptor and insulin-like growth factor-I (IGF-I), and decreased protein levels of ER-alpha (ER alpha) were found in genistein-treated LM cells, but not SMC. Additionally, extracellular regulated kinase (ERK), Src homology/collagen (Shc) and ER alpha were transiently activated, and interactions between ER alpha and IGF-I receptor (IGF-IR) were rapidly induced by genistein in LM cells. Using ER antagonist ICI 182,780 and MAPK/ERK kinase (MEK) inhibitor PD98059, we found that these early events were inhibited and the proliferative effect of genistein on LM cells was abrogated.

CONCLUSIONS

ER alpha is involved in the transient activation of ERK/mitogen activated protein kinase (MAPK) by genistein via its early association with IGF-IR, leading to hyper-responsiveness of LM cells and confirming that ER signaling is enhanced by activation of ERK/MAPK in LM cells.

Stimulatory and inhibitory effects of genistein on human uterine leiomyoma cell proliferation are influenced by the concentration

BACKGROUND

Due to dietary exposure of women to genistein, a soy-derived phytoestrogen, and the estrogen responsiveness of uterine leiomyomas 'fibroids', we evaluated the effects of genistein (0.001-50 microg/ml) on human uterine leiomyoma (UtLM) cells versus uterine smooth muscle cells (UtSMCs) in vitro.

METHODS

Light microscopy was used to determine the effects of genistein on cell morphology. Proliferation was assessed using a colorimetric assay and proliferating cell nuclear antigen (PCNA) immunocytochemistry. Flow cytometry was used to quantitate cells in the S-phase and those undergoing apoptosis. A fluorometric assay and confocal microscopy were used to detect caspase-3 activity and apoptotic bodies, respectively.

RESULTS

In UtLM cells, low concentrations (< or = 1 microg/ml) of genistein stimulated proliferation, increased PCNA labeling and the percentage of cells in the S-phase, but this did not occur in UtSMCs. Higher concentrations (> or = 10 microg/ml) of genistein adversely affected the morphology, significantly inhibited proliferation, decreased PCNA labeling, increased caspase-3 activity and induced apoptosis in both cell types.

CONCLUSIONS

Genistein's effects are concentration-dependent in both cell lines. Lower concentrations elicit proliferative effects on UtLM cells only; whereas, higher concentrations alter morphology, inhibit proliferation, and increase caspase activity and apoptosis in both cell types, with the latter two effects being more extensive in UtSMCs.

Experiences of new product development in the medical device industry

A survey of medical device professionals has revealed the factors that influence the development time and market success of new products. The vital elements that deliver commercial success are reported here.

Upregulation of estrogen receptor expression in the uterus of ovariectomized B6C3F1 mice and Ishikawa cells treated with bromoethane

In a 2-year NTP bioassay, Bromoethane (BE) was found to induce endometrial neoplasms in the uterus of B6C3F1 mice [; ]. In women, hormonal influences, such as "unopposed" estrogenic stimulus, have been implicated as important etiologic factors in uterine cancer. BE, however, does not affect the serum concentrations of sex hormones in female B6C3F1 mice [] and the mechanism of BE-induced uterine carcinogenesis still remains unclear. In the present study, we examined the estrogenic effects of BE on the uterus of ovariectomized B6C3F1 mice and on Ishikawa cells. Groups of 6 mice were given daily s.c. injections of 0, 100, 500 or 1000 mg BE/kg for 3 consecutive days. Mice treated with 17beta-estradiol served as positive controls. Mice were necropsied 24 h after the final injection, and uteri were weighed and examined histologically and immunohistochemically along with the vagina. Changes observed in the estrogen-treated mice included increased uterine weights, edema and inflammation of the endometrium, increased epithelial layers of the uterine and vaginal lumens and keratinization of the vaginal epithelium. In the BE-treated mice, no such changes occurred; however, immunohistochemical staining of the uterus revealed a significant increase in immunoexpression of the estrogen receptor alpha (ERalpha) in the two higher dose groups. Analysis of mRNA also showed slightly increased uterine ERalpha expression in these groups. Upregulated expression of ERalpha was confirmed in BE-treated Ishikawa cells, in which Western blotting analyses identified an intense signal at approximately 66 kDa, which is consistent with ERalpha. These data suggest that upregulated expression of ERalpha may be important in the induction of endometrial neoplasms in BE-treated mice.

Estrogen-induced changes in IGF-I, Myb family and MAP kinase pathway genes in human uterine leiomyoma and normal uterine smooth muscle cell lines

Many studies have implicated numerous hormones, growth factors, cytokines and other signal transduction molecules in the pathogenesis of uterine leiomyoma. Estrogen and estrogen-related genes are thought to play a key role in the growth of uterine leiomyomas, but the molecular mechanisms are unclear. In an attempt to investigate various pathways that might be involved in estrogen-regulated uterine leiomyoma growth as well as to identify any novel effector genes, microarray studies comparing estrogen-treated uterine leiomyoma cells (UtLM) and normal myometrial cells to untreated cells were performed. Several genes were differentially expressed in estrogen treated UtLM cells, including insulin-like growth factor-I (IGF-I) and others potentially involved in the IGF-I signalling pathway, specifically genes for A-myb, a transcription factor which promotes cell cycle progression and for MKP-1, a dual specificity phosphatase that dephosphorylates mitogen-activated protein kinase. IGF-I and A-myb were up-regulated in estrogen-treated cells while MKP-1 was down-regulated. Two other cell cycle promoting genes, c-fos and myc, were also down-regulated in estrogen treated UtLM cells. These genes are typically up-regulated in response to estrogen in some cells, notably breast epithelial cells, yet consistently have lower expression levels in uterine leiomyoma tissue when compared to autologous myometrium. Our results demonstrate some novel genes that may play a role in the growth of uterine leiomyoma, strengthen the case for involvement of the IGF-I pathway in the response of UtLM to estrogen and corroborate evidence that uterine smooth muscle cells respond to estrogen with a different gene expression pattern than that seen in epithelial cells.

Gender differences in TNF-alpha levels among obese vs nonobese Latino children

OBJECTIVE

To examine the relationships between TNF-alpha, obesity, and insulin resistance among prepubescent children.

DESIGN

Cross-sectional study.

SETTING AND SUBJECTS

Data were collected from 112 nondiabetic Latino schoolchildren from public schools in three South Florida communities. Of the enrolled participants, 43.8% were obese (BMI 95th percentile) and 51.8% presented with a family history of type 2 diabetes mellitus (T2DM). With one exception, all demonstrated normal glucose tolerance.

INTERVENTIONS

Plasma TNF-alpha levels were determined with enzyme-linked immunosorbance assay (ELISA). Homeostasis model assessment (HOMA-IR) was calculated as an index of insulin resistance. Mean levels of TNF-alpha among obese vs nonobese children were compared with a one-way analysis of variance with two groups, and the association between TNF-alpha and HOMA-IR was assessed with a Pearson's correlation.

RESULTS

Higher circulating TNF-alpha levels were revealed among nonobese vs obese children. Nonobese girls demonstrated higher TNF-alpha levels than obese girls, whereas there were no significant differences for boys. There were no significant differences after stratifying for family history of T2DM. There was a modest relationship between increased TNF-alpha levels and decreased insulin resistance.

CONCLUSIONS

The observed elevated circulating TNF-alpha concentrations among leaner participants may reflect an inflammatory process that has been associated with higher levels of physical fitness in both adults and prepubescent children. This effect may remain stronger for prepubescent girls, and the mechanism may be attenuated by the hormonal changes that occur with the onset of puberty.

Interactions of the renin-angiotensin system and alpha-1 adrenoceptors on renal hemodynamics in healthy and acute renal failure rats: the role of nitric oxide

The renin-angiotensin (RAS) and the alpha1 sympathetic nervous system (SNS) interact at different levels in cardiovascular regulation. Concurrent use of angiotensin-converting enzyme (ACE) inhibitors and alpha1 receptor antagonists result in a synergistic antihypertensive action and is of wide utility in cardiovascular therapy. We examined the impact of concurrent inhibition of RAS (captopril or losartan) and the SNS (prazosin) before and after acute nitric oxide (NO) synthase inhibition with L-nitro-L-arginine methyl ester (L-NAME) on renal cortical perfusion (RCF) and blood pressure (MAP) in healthy and acute ischemic renal failure (ARF) rats (n = 6). Captopril or losartan reduced MAP and increased RCF more in healthy (p < 0.001) and ARF rats (p < 0.02). Prazosin alone reduced both MAP and RCF (p < 0.001). The combination of prazosin with captopril or losartan caused an additive fall in MAP, and mitigated the fall in RCF. Captopril + prazosin caused a profound fall in RCF following L-NAME, in healthy but not ARF rats (p < 0.001). Acetylcholine (Ach), a vasodilator which stimulates endogenous NO production caused a profound paradoxical fall in RCF in ARF, but not in healthy rats (p < 0.001 ANOVA). These results indicate a significant interaction between angiotensin II and phenylephrine in renal vasomotion. It establishes that endogenous NO homeostatically opposes angiotensin II-alpha1-mediated renal vasoconstriction, and that the vasodilator role of NO is diminished in ARF. The paradoxical fall in RCF induced by Ach in ARF is speculated to result, at least in part, from the formation of peroxynitrite (ONOO-), which acts as a renal vasoconstrictor, following the combination of ischemia-generated super oxide anion (O-2), with endothelial NO released by Ach.