Mammary Gland Evaluation in Juvenile Toxicity Studies: Temporal Developmental Patterns in the Male and Female Harlan Sprague-Dawley Rat.

There are currently no reports describing mammary gland development in the Harlan Sprague-Dawley (HSD) rat, the current strain of choice for National Toxicology Program (NTP) testing. Our goals were to empower the NTP, contract labs, and other researchers in understanding and interpreting chemical effects in this rat strain. To delineate similarities/differences between the female and male mammary gland, data were compiled starting on embryonic day 15.5 through postnatal day 70. Mammary gland whole mounts, histology sections, and immunohistochemically stained tissues for estrogen, progesterone, and androgen receptors were evaluated in both sexes; qualitative and quantitative differences are highlighted using a comprehensive visual timeline. Research on endocrine disrupting chemicals in animal models has highlighted chemically induced mammary gland anomalies that may potentially impact human health. In order to investigate these effects within the HSD strain, 2,3,7,8-tetrachlorodibenzo-p-dioxin, diethylstilbestrol, or vehicle control was gavage dosed on gestation day 15 and 18 to demonstrate delayed, accelerated, and control mammary gland growth in offspring, respectively. We provide illustrations of normal and chemically altered mammary gland development in HSD male and female rats to help inform researchers unfamiliar with the tissue and may facilitate enhanced evaluation of both male and female mammary glands in juvenile toxicity studies.

Perinatal environmental exposures affect mammary development, function, and cancer risk in adulthood.

Puberty is an important transition that enables reproduction of mammalian species. Precocious puberty, specifically early thelarche (the appearance of breast "buds"), in girls of multiple ethnic backgrounds is a major health problem in the United States and other countries. The cause for a continued decrease in the age of breast development in girls is unknown, but environmental factors likely play a major role. Laboratory and epidemiological studies have identified several individual environmental factors that affect breast development, but further progress is needed. Current research needs include increased attention to and recording of prenatal and neonatal environmental exposures, testing of marketed chemicals for effects on the mammary gland, and understanding of the mammary gland-specific mechanisms that are altered by chemicals. Such research is required to halt the increasing trend toward puberty at earlier ages.

Exposure to diethylstilbestrol during sensitive life stages: a legacy of heritable health effects.

Diethylstilbestrol (DES) is a potent estrogen mimic that was predominantly used from the 1940s to the 1970s by pregnant women in hopes of preventing miscarriage. Decades later, DES is known to enhance breast cancer risk in exposed women and cause a variety of birth-related adverse outcomes in their daughters such as spontaneous abortion, second trimester pregnancy loss, preterm delivery, stillbirth, and neonatal death. Additionally, children exposed to DES in utero suffer from sub/infertility and cancer of reproductive tissues. DES is a pinnacle compound that demonstrates the fetal basis of adult disease. The mechanisms of cancer and endocrine disruption induced by DES are not fully understood. Future studies should focus on common target tissue pathways affected and the health of the DES grandchildren.

Clinical characteristics and health care resource use of patients at risk for wild-type transthyretin amyloid cardiomyopathy identified by machine learning model.

BACKGROUND: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, life-threatening systemic disorder that is an underrecognized cause of heart failure (HF). When the diagnosis of wild-type ATTR-CM (ATTRwt-CM) is delayed, patients often undergo additional assessments, deferring appropriate management as symptoms potentially worsen. Prompt recognition of patients at risk for ATTRwt-CM is essential to facilitate earlier diagnosis and disease-modifying treatment. A previously developed machine learning model performed well in identifying ATTRwt-CM in patients with HF vs controls with nonamyloid HF using medical claims/electronic health records, providing a systematic framework to raise disease suspicion. OBJECTIVE: To further evaluate this model's performance in identifying ATTRwt-CM using a large claims database of older adults with HF and confirmed ATTRwt-CM or nonamyloid HF; and to explore the characteristics and health care resource utilization (HCRU) of patients with confirmed and suspected ATTRwt-CM. METHODS: In this retrospective study, the prior model was applied using Humana administrative claims for patients diagnosed with ATTRwt-CM (cases) and nonamyloid HF (controls [1:1]). Patients were aged 65-89 years, had at least 2 claims for HF diagnosis (2015-2020), and were continuously enrolled in a Medicare Advantage prescription drug plan for at least 12 months before and at least 6 months after HF diagnosis. For the assessment of characteristics and HCRU, the suspected risk level was categorized based on the predicted probability (PP) from model output (high, moderate, and low risk: PP≥0.70; ≥0.50 and < 0.70; and < 0.50, respectively). RESULTS: Of 267,025 eligible patients, 119 (0.04%) had confirmed ATTRwt-CM; of 266,906 patients with nonamyloid HF, 10,997 (4.1%), 68,174 (25.5%), and 187,735 (70.3%) were categorized as high, moderate, and low risk for ATTRwt-CM, respectively. The model demonstrated sensitivity/specificity/accuracy/receiver operating characteristic area under the concentration-time curve of 88%/65%/77%/0.89, respectively, in differentiating ATTRwt-CM from nonamyloid HF. In patients with confirmed ATTRwt-CM, the mean (SD) time between HF and ATTRwt-CM diagnoses was 751 (528) days; 65% and 48% were hospitalized before and after ATTRwt-CM diagnosis, respectively. Atrial fibrillation was more common in patients with confirmed ATTRwt-CM and high risk (39% and 55%) vs low risk (27%). Hospitalization and emergency department visits after HF diagnosis were reported in 57% and 46% of patients with high ATTRwt-CM risk, respectively. CONCLUSIONS: The ATTRwt-CM predictive model performed well in identifying disease risk in the Humana Research Database. Patients at high risk for ATTRwt-CM had high HCRU and may benefit from the earlier suspicion of ATTRwt-CM. The model may be used as a tool to identify patients with a suspected high risk for the disease to facilitate earlier detection and treatment. DISCLOSURES: This study was sponsored by Pfizer. Medical writing support was provided by Donna McGuire of Engage Scientific Solutions and funded by Pfizer. Drs Bruno and Schepart and Mr Casey are currently employees of Pfizer and equity holders in this publicly traded company. Dr Reed was an employee of Pfizer at the time that this analysis was planned and conducted. Mr Sheer and Dr Simmons are currently employees of Humana, which received research funding from Pfizer. Dr Nair was an employee of Humana at the time that this analysis was planned and conducted.

Implementing a Machine-Learning-Adapted Algorithm to Identify Possible Transthyretin Amyloid Cardiomyopathy at an Academic Medical Center.

Background: Wild-type transthyretin amyloid cardiomyopathy (ATTR-CM) is a frequently under-recognized cause of heart failure (HF) in older patients. To improve identification of patients at risk for the disease, we initiated a pilot program in which 9 cardiac/non-cardiac phenotypes and 20 high-performing phenotype combinations predictive of wild-type ATTR-CM were operationalized in electronic health record (EHR) configurations at a large academic medical center. Methods: Inclusion criteria were age >50 years and HF; exclusion criteria were end-stage renal disease and prior amyloidosis diagnoses. The different Epic EHR configurations investigated were a clinical decision support tool (Best Practice Advisory) and operational/analytical reports (Clarity™, Reporting Workbench™, and SlicerDicer); the different data sources employed were problem list, visit diagnosis, medical history, and billing transactions. Results: With Clarity, among 45 051 patients with HF, 4006 patients (8.9%) had ⩾1 phenotype combination associated with increased risk of wild-type ATTR-CM. Across all data sources, 2 phenotypes (cardiomegaly; osteoarthrosis) and 2 combinations (carpal tunnel syndrome + HF; atrial fibrillation + heart block + cardiomegaly + osteoarthrosis) generated the highest proportions of patients for wild-type ATTR-CM screening. Conclusion: All EHR configurations tested were capable of operationalizing phenotypes or phenotype combinations to identify at-risk patients; the Clarity report was the most comprehensive.

Application of near-infrared spectroscopy during fetal cardiac surgery.

BACKGROUND: Near-infrared spectroscopy (NIRS) has been shown to provide reliable noninvasive monitoring of regional oxygenation in a variety of clinical settings. We set out to test its feasibility as a monitor of fetal and placental oxygenation during fetal cardiac surgery. MATERIALS AND METHODS: Six ovine fetuses from 98-110 ds gestation were placed on fetal bypass for 30 min and followed post-bypass for 2 h. A NIRS probe (MI INVOS 5100B; Somanetics, Troy, MI) was placed on the pregnant uterine horn during and after fetal surgery. NIRS values were compared with blood gas values obtained by direct sampling from umbilical circulation. RESULTS: NIRS values positively correlated with umbilical venous oxygen saturation (R(2)=0.891, P<0.01) and partial oxygen pressure values (R(2)=0.810, P<0.01). NIRS values also correlated to a lesser extent with umbilical venous pH and pCO(2), and fetal arterial pH, pO(2), and oxygen saturation. CONCLUSIONS: This is the first report of application of NIRS in the setting of fetal surgery. NIRS permits noninvasive assessment of placental oxygen saturation and pO(2). This technology is a simple and useful tool for real-time monitoring of oxygen delivery to the fetus during maternal-fetal cardiac interventions and of overall well-being of the fetal-placental unit.

The absence of ER-ß results in altered gene expression in ovarian granulosa cells isolated from in vivo preovulatory follicles.

Determining the spatial and temporal expression of genes involved in the ovulatory pathway is critical for the understanding of the role of each estrogen receptor in the modulation of folliculogenesis and ovulation. Estrogen receptor (ER)-ß is highly expressed in ovarian granulosa cells, and mice lacking ER-ß are subfertile due to inefficient ovulation. Previous work has focused on isolated granulosa cells or cultured follicles and, although informative, provides confounding results due to the heterogeneous cell types present including granulosa and theca cells and oocytes and exposure to in vitro conditions. Herein we isolated preovulatory granulosa cells from wild-type (WT) and ERß-null mice using laser capture microdissection to examine the genomic transcriptional response downstream of pregnant mare serum gonadotropin (mimicking FSH) and pregnant mare serum gonadotropin/human chorionic gonadotropin (mimicking LH) stimulation. This allows for a direct comparison of in vivo granulosa cells at the same stage of development from both WT and ERß-null ovaries. ERß-null granulosa cells showed altered expression of genes known to be regulated by FSH (Akap12 and Runx2) as well as not previously reported (Arnt2 and Pou5f1) in WT granulosa cells. Our analysis also identified 304 genes not previously associated with ERß in granulosa cells. LH-responsive genes including Abcb1b and Fam110c show reduced expression in ERß-null granulosa cells; however, novel genes including Rassf2 and Megf10 were also identified as being downstream of LH signaling in granulosa cells. Collectively, our data suggest that granulosa cells from ERß-null ovaries may not be appropriately differentiated and are unable to respond properly to gonadotropin stimulation.

A single gestational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin disrupts the adult uterine response to estradiol in mice.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) given as a cotreatment with estrogen exhibits antiestrogenic properties on the rodent adult uterus, but less is understood regarding hormonal responsiveness of the adult uterus from animals having been exposed to TCDD during critical periods of development. We characterized the inhibitory effects of TCDD (T) exposure at gestational day 15 (GD15), 4 weeks, and 9 weeks of age (TTT) on the adult uterus following hormone treatment. TTT-exposed mice in response to hormone treatment exhibited a blunted weight increase, had fewer uterine glands, displayed morphological anomalies, and had marked decreases in the hormonal regulation of genes involved in fluid transport (Aqp3 and Aqp5), cytoarchitectural (Dsc2 and Sprr2A), and immune (Lcn2 and Ltf) regulation. To determine if the 9-week exposure was responsible for the blunted uterine response, due to the 7- to 11-day half-life of TCDD in mice, a second set of experiments was performed to examine exposure to TCDD given at GD15, GD15 only (cross-fostered at birth), only during lactation (cross-fostered at birth), or at GD15 and 4 weeks of age. Our studies demonstrate that a single developmental TCDD exposure at GD15 is sufficient to elicit a blunted adult uterine response to estradiol and is due in part to fewer gland numbers and the reduced expression of forkhead box A2 (FoxA2), a gene involved in gland development. Together, these results provide insight regarding the critical nature of in utero exposure and the potential impact on ensuing uterine biology and reproductive health later in life.

The effects of isolated and integrated 'core stability' training on athletic performance measures: a systematic review.

BACKGROUND: Core stability training, operationally defined as training focused to improve trunk and hip control, is an integral part of athletic development, yet little is known about its direct relation to athletic performance. OBJECTIVE: This systematic review focuses on identification of the association between core stability and sports-related performance measures. A secondary objective was to identify difficulties encountered when trying to train core stability with the goal of improving athletic performance. DATA SOURCES: A systematic search was employed to capture all articles related to athletic performance and core stability training that were identified using the electronic databases MEDLINE, CINAHL and SPORTDiscus™ (1982-June 2011). STUDY SELECTION: A systematic approach was used to evaluate 179 articles identified for initial review. Studies that performed an intervention targeted toward the core and measured an outcome related to athletic or sport performances were included, while studies with a participant population aged 65 years or older were excluded. Twenty-four in total met the inclusionary criteria for review. STUDY APPRAISAL AND SYNTHESIS METHODS: Studies were evaluated using the Physical Therapy Evidence Database (PEDro) scale. The 24 articles were separated into three groups, general performance (n = 8), lower extremity (n = 10) and upper extremity (n = 6), for ease of discussion. RESULTS: In the majority of studies, core stability training was utilized in conjunction with more comprehensive exercise programmes. As such, many studies saw improvements in skills of general strengths such as maximum squat load and vertical leap. Surprisingly, not all studies reported measurable increases in specific core strength and stability measures following training. Additionally, investigations that targeted the core as the primary goal for improved outcome of training had mixed results. LIMITATIONS: Core stability is rarely the sole component of an athletic development programme, making it difficult to directly isolate its affect on athletic performance. The population biases of some studies of athletic performance also confound the results. CONCLUSIONS: Targeted core stability training provides marginal benefits to athletic performance. Conflicting findings and the lack of a standardization for measurement of outcomes and training focused to improve core strength and stability pose difficulties. Because of this, further research targeted to determine this relationship is necessary to better understand how core strength and stability affect athletic performance.

Histopathologic changes in the uterus, cervix and vagina of immature CD-1 mice exposed to low doses of perfluorooctanoic acid (PFOA) in a uterotrophic assay.

The estrogenic and antiestrogenic potential of perfluorooctanoic acid (PFOA) was assessed using an immature mouse uterotrophic assay and by histologic evaluation of the uterus, cervix and vagina following treatment. Female offspring of CD-1 dams were weaned at 18days old and assigned to groups of equal weight, and received 0, 0.01, 0.1, or 1mg PFOA/kg BW/d by gavage with or without 17-ß estradiol (E(2), 500µg/kg/d) from PND 18-20 (n=8/treatment/block). At 24h after the third dose (PND 21), uteri were removed and weighed. Absolute and relative uterine weights were significantly increased in the 0.01mg/kg PFOA only group. Characteristic estrogenic changes were present in all E(2)-treated mice; however, they were minimally visible in the 0.01 PFOA only mice. These data suggest that at a low dose PFOA produces minimal histopathologic changes in the reproductive tract of immature female mice, and does not antagonize the histopathologic effects of E(2).

Myocardial function after fetal cardiac bypass in an ovine model.

OBJECTIVE: Fetal cardiac surgery might improve the prognosis of certain complex congenital heart defects that have significant associated mortality and morbidity in utero or after birth. An important step in translating fetal cardiac surgery is identifying potential mechanisms leading to myocardial dysfunction after bypass. The hypothesis was that fetal cardiac bypass results in myocardial dysfunction, possibly because of perturbation of calcium cycling and contractile proteins. METHODS: Midterm sheep fetuses (n = 6) underwent 30 minutes of cardiac bypass and 120 minutes of monitoring after bypass. Sonomicrometric and pressure catheters inserted in the left and right ventricles measured myocardial function. Cardiac contractile and calcium cycling proteins, along with calpain, were analyzed by means of immunoblotting. RESULTS: Preload recruitable stroke work (slope of the regression line) was reduced at 120 minutes after bypass (right ventricle: baseline vs 120 minutes after bypass, 38.6 ± 6.8 vs 20.4 ± 4.8 [P = .01]; left ventricle: 37 ± 7.3 vs 20.6 ± 3.9, respectively [P = .01]). Tau (in milliseconds), a measure of diastolic relaxation, was increased in both ventricles (right ventricle: baseline vs 120 minutes after bypass, 32.7 ± 4.5 vs 67.8 ± 9.4 [P < .01]); left ventricle: 26.1 ± 3.2 vs 63.2 ± 11.2, respectively [P = .01]). Cardiac output was lower and end-diastolic pressures were higher in the right ventricle, but not in the left ventricle, after bypass compared with baseline values. Right ventricular troponin I was degraded by increased calpain activity, and protein levels of sarco(endo)plasmic reticulum calcium ATPase were reduced in both ventricles. CONCLUSIONS: Fetal cardiac bypass was associated with myocardial dysfunction and disruption of calcium cycling and contractile proteins. Minimizing myocardial dysfunction after cardiac bypass is important for successful fetal surgery to repair complex congenital heart defects.

Fetal right ventricular myocardial function is better preserved by fibrillatory arrest during fetal cardiac bypass.

BACKGROUND: Protection and preservation of fetal myocardial function are important for successful fetal intracardiac repair. Our objective was to determine fetal biventricular cardiac performance after two cardiac-arrest techniques. METHODS: Three groups of midterm ovine fetuses underwent 90-minute bypass. A control group (no arrest shams, n = 3), and two groups that included 20 minutes of arrest, using fibrillatory (n = 3) or blood cardioplegia (n = 3), were compared. Blood cardioplegia consisted of 4:1 cold blood to crystalloid solution induction every 10 minutes, followed by a warm shot terminal dose before clamp removal. Myocardial function variables from biventricular intracardiac pressure catheters, and 3-axes cardiac sonomicrometry, fetal hemodynamics, and arterial blood gases were continuously recorded. Fetal myocardium was collected for troponin-I analysis at 90 minutes. Statistical analysis was by two-way analysis of variance for repeated measures. RESULTS: Compared with sham, right ventricular myocardial contractility was reduced with plegia but not fibrillation at 90 minutes after arrest: dP/dt max (511 ± 347 vs 1208 ± 239, p < 0.01) and preload-recruitable stroke work (7.2 ± 8.5 vs 32.3 ± 14.6, p < 0.01). Right ventricular end diastolic pressure-volume relationship (ventricular stiffness) worsened by 90 minutes for plegia vs fibrillation (0.84 ± 0.18 vs 0.25 ± 0.16, p < 0.05). There were no differences in left ventricle performance between groups. Fetal heart rate increased in shams by 30 minutes after arrest compared with both arrest groups (p < 0.05). Right ventricular troponin-I degradation increased with plegia, but not fibrillation, compared with sham (p < 0.05). CONCLUSIONS: In vivo, fetal right ventricular contractile function deteriorates with a common blood-plegia regimen. Fibrillatory arrest better preserves right ventricular function, the dominant ventricle in fetal life, for short arrest periods.