Chronic kidney disease increases cost of care and readmission risk after shoulder arthroplasty

BACKGROUND

Chronic kidney disease (CKD) is associated with adverse outcomes and higher costs after lower extremity arthroplasty from higher rates of infection, aseptic loosening, and transfusion and longer hospital length of stay (LOS). The purpose of this study was to compare health care utilization and 90-day encounter charges after shoulder arthroplasty (SA) in patients with and without renal disease. A secondary aim was to define the characteristics of patients with renal disease.

METHODS

We conducted a retrospective cohort study of all patients who underwent primary SA from January 2015 to December 2019 by a single surgeon at a single institution. Patients without a baseline glomerular filtration rate (GFR) were excluded. We evaluated results for patients with CKD (GFR ≤59 mL/min/1.73 m2) and without CKD (GFR ≥60 mL/min/1.73 m2). Univariate regression was performed to assess the influence of CKD on health care utilization, including LOS, transfusion, and risk for emergency department (ED) revisit or readmission during the 90-day postoperative period. In addition, 90-day encounter charges, revisit charges, and ED charges for patients with CKD were compared with those for patients with normal renal function. Last, multivariable linear regression models were used to assess the effect of estimated GFR on total 90-day encounter charges.

RESULTS

A total of 514 patients met the study inclusion criteria, with 125 having CKD and 389 having normal GFR. Patients with CKD were more likely to require transfusion (odds ratio: 16.2 [confidence interval: 1.9, 139.7], P = .011) despite similar intraoperative estimated blood loss (156.9 ± 132.5 mL vs. 153.8 ± 89.7 mL; P = .768). In addition, patients with CKD had longer LOS (2.8 ± 1.3 days vs. 2.3 ± 1.0 days; P < .001), had higher 90-day readmission rates (P = .001), were more likely to visit the ED within 90 days after SA (P = .018), and had higher total 90-day encounter charges ($37,769 ± $6901 vs. $35,684 ± $5312; P = .001). Each unit increase in eGFR independently reduced total encounter charges by $67 (-$132, -$2; P = .043); dialysis patients incurred higher total 90-day encounter charges compared with patients with less severe renal disease ($42,733 ± $8985 vs. $37,531 ± $6749; P = .002). Also, patients with CKD were older (73.2 ± 8.9 vs. 68.1 ± 9.4 years; P < .001); had a lower preoperative hemoglobin level (12.4 ± 1.5 g/dL vs. 13.4 ± 1.5 g/dL; P < .001), higher American Society of Anesthesiologists score (P < .001), and more preoperative comorbidities (5.9 ± 2.9 vs. 5.0 ± 3.1; P < .001); and were more likely to use opioids preoperatively (P = .043).

CONCLUSION

Patients with CKD have a higher risk for blood transfusion, ED visits, and readmission after SA, with higher total 90-day encounter charges. Identifying and optimizing this patient population before surgery can reduce costs and improve outcomes, which benefits patients, physicians, institutions, and payors.

Anterior Labral Reconstruction With Biceps Autograft for Anterior Shoulder Instability

Shoulder instability is a common problem, with current research focused on understanding the implications of humeral and glenoid bone loss. Soft tissue injury, including damage to the anterior labrum, deformity of the capsule, and disruption of the inferior glenohumeral ligament, also contributes to the pathology of shoulder dislocation with implications for recurrent instability. Anatomic placement of the labral tissue and restoration of capsular tension are essential components of successful arthroscopic Bankart repair (ABR). Patients who meet criteria for ABR with a diminutive, ruptured, or absent anterior labrum at the time of arthroscopic stabilization present a significant challenge to repair. In this Technical Note, we demonstrate a technique using biceps autograft to reconstruct the anterior labrum.

MAP3K1 regulates female reproductive tract development

Mitogen-activated protein 3 kinase 1 (MAP3K1) has a plethora of cell type-specific functions not yet fully understood. Herein, we describe a role for MAP3K1 in female reproductive tract (FRT) development. MAP3K1 kinase domain-deficient female mice exhibited an imperforate vagina, labor failure and infertility. These defects corresponded with shunted Müllerian ducts (MDs), the embryonic precursors of FRT, that manifested as a contorted caudal vagina and abrogated vaginal-urogenital sinus fusion in neonates. The MAP3K1 kinase domain is required for optimal activation of the Jun-N-terminal kinase (JNK) and cell polarity in the MD epithelium, and for upregulation of WNT signaling in the mesenchyme surrounding the caudal MD. The MAP3K1-deficient epithelial cells and MD epithelium had reduced expression of WNT7B ligands. Correspondingly, conditioned media derived from MAP3K1-competent, but not -deficient, epithelial cells activated a TCF/Lef-luciferase reporter in fibroblasts. These observations indicate that MAP3K1 regulates MD caudal elongation and FRT development, in part through the induction of paracrine factors in the epithelium that trans-activate WNT signaling in the mesenchyme.

The Role of MAP3K1 in the Development of the Female Reproductive Tract

Mitogen-Activated Protein 3 Kinase 1 (MAP3K1) is a dynamic signaling molecule with a plethora of cell-type specific functions, most of which are yet to be understood. Here we describe a role for MAP3K1 in the development of female reproductive tract (FRT). MAP3K1 kinase domain-deficient ( Map3k1 ^ΔKD ) females exhibit imperforate vagina, labor failure, and infertility. These defects correspond to a shunted Müllerian duct (MD), the principle precursor of the FRT, in embryos, while they manifest as a contorted caudal vagina with abrogated vaginal-urogenital sinus fusion in neonates. In epithelial cells, MAP3K1 acts through JNK and ERK to activate WNT, yet in vivo MAP3K1 is crucial for WNT activity in mesenchyme associated with the caudal MD. Expression of Wnt7b is high in wild type, but low in Map3k1 knockout MD epithelium and MAP3K1-deficient keratinocytes. Correspondingly, conditioned media derived from MAP3K1-competent epithelial cells activate TCF/Lef-luciferase reporter in fibroblasts, suggesting that MAP3K1-induced factors released from epithelial cells trans-activate WNT signaling in fibroblasts. Our results reveal a temporal-spatial and paracrine MAP3K1-WNT crosstalk contributing to MD caudal elongation and FRT development.

Highlights

MAP3K1 deficient female mice exhibit imperforate vagina and infertilityLoss of MAP3K1 kinase activity impedes Müllerian duct (MD) caudal elongation and fusion with urogenital sinus (UGS) in embryogenesisThe MAP3K1-MAPK pathway up-regulates WNT signaling in epithelial cellsMAP3K1 deficiency down-regulates Wnt7b expression in the MD epithelium and prevents WNT activity in mesenchyme of the caudal MD.

Endometriosis in the Mouse: Challenges and Progress Toward a ‘Best Fit’ Murine Model

Endometriosis is a prevalent gynecologic condition associated with pelvic pain and infertility characterized by the implantation and growth of endometrial tissue displaced into the pelvis via retrograde menstruation. The mouse is a molecularly well-annotated and cost-efficient species for modeling human disease in the therapeutic discovery pipeline. However, as a non-menstrual species with a closed tubo-ovarian junction, the mouse poses inherent challenges as a preclinical model for endometriosis research. Over the past three decades, numerous murine models of endometriosis have been described with varying degrees of fidelity in recapitulating the essential pathophysiologic features of the human disease. We conducted a search of the peer-reviewed literature to identify publications describing preclinical research using a murine model of endometriosis. Each model was reviewed according to a panel of ideal model parameters founded on the current understanding of endometriosis pathophysiology. Evaluated parameters included method of transplantation, cycle phase and type of tissue transplanted, recipient immune/ovarian status, iterative schedule of transplantation, and option for longitudinal lesion assessment. Though challenges remain, more recent models have incorporated innovative technical approaches such as in vivo fluorescence imaging and novel hormonal preparations to overcome the unique challenges posed by murine anatomy and physiology. These models offer significant advantages in lesion development and readout toward a high-fidelity mouse model for translational research in endometriosis.

Modifiable risk factors increase length of stay and 90-day cost of care after shoulder arthroplasty

BACKGROUND

Baseline health conditions can negatively impact cost of care and risk of complications after joint replacement, necessitating additional care and incurring higher costs. Bundled payments have been used for hip and knee replacement and the Centers for Medicare & Medicaid Services (CMS) is testing bundled payments for upper extremity arthroplasty. The purpose of this study was to determine the impact of predefined modifiable risk factors (MRFs) on total encounter charges, hospital length of stay (LOS), related emergency department (ED) visits and charges, and related hospital readmissions within 90 days after shoulder arthroplasty.

METHODS

We queried the electronic medical record (EPIC) for all shoulder arthroplasty cases under DRG 483 within a regional 7-hospital system between October 2015 and December 2019. Data was used to calculate mean LOS, total 90-day charges, related emergency department (ED) visits and charges, and related hospital readmissions after shoulder arthroplasty. Data for patients who had 1 or more MRFs, defined as anemia (hemoglobin < 10 g/dL), malnutrition (albumin < 3.4 g/dL), obesity (BMI > 40), uncontrolled diabetes (random glucose > 180 mg/dL or glycated hemoglobin > 8.0%), tobacco use (International Classification of Diseases, Tenth Revision, code indicating patient is a smoker), and opioid use (opioid prescription within 90 days of surgery), were evaluated as potential covariates to assess the relationship between MRFs and total encounter charges, LOS, ED visits, ED charges, and hospital readmissions.

RESULTS

A total of 1317 shoulder arthroplasty patients were identified. Multivariable analysis demonstrated that anemia (+$19,847, confidence interval [CI] $15,743, $23,951; P < .001), malnutrition (+$5850, CI $3712, $7988; P < .001), and obesity (+$2762, CI $766, $4758, P = .007) independently contributed to higher charges after shoulder arthroplasty. Mean LOS was higher in patients with anemia (5.0 ± 4.0 days vs. 2.2 ± 1.6 days, P < .001), malnutrition (3.7 ± 2.8 days vs. 2.2 ± 1.5 days, P < .001), and uncontrolled diabetes (2.8 ± 2.8 days vs. 2.3 ± 1.7 days, P = .019). Univariate risk factors associated with a significant increase in total 90-day encounter charges included anemia (+$19,345, n = 37, P < .001), malnutrition (+$6971, n = 116, P < .001), obesity (+$2615, n = 184, P = .011), and uncontrolled diabetes (+$4377, n = 66, P = .011). Univariate risk for readmission within 90 days was higher in patients with malnutrition (odds ratio 3.0, CI 1.8, 4.9; P < .001).

CONCLUSION

Malnutrition, obesity, and anemia contribute to significantly higher costs after shoulder arthroplasty. Medical strategies to optimize patients before shoulder arthroplasty are warranted to reduce total 90-day encounter charges, length of stay, and risk of readmission within 90 days of surgery. Optimizing patient health before shoulder surgery will positively impact outcomes and cost containment for patients, institutions, and payors after shoulder arthroplasty.

Unique Sensitivity of Uterine Tissue and the Immune System for Endometriotic Lesion Formation

Endometriosis is a debilitating disease that affects about 10% of reproductive-aged adolescents and women. The etiology of the disease is unknown; however, a prevailing hypothesis is that endometriosis develops from retrograde menstruation, where endometrial tissue and fluids flow back through the oviducts into the peritoneal cavity. There is no cure for endometriosis, and symptoms are treated palliatively. Despite the advances in knowledge, the complexity of endometriosis etiology is still unknown. Recent work by our group suggests that the initiation of endometriosis is immune-dependent. Using a mouse model of endometriosis, we hypothesized the initiation of endometriosis is immune regulated and uterine endometrium specific. In the absence of a functional immune system non-obese diabetic/severe combined immunodeficiency (NOD/SCID mice), endometriotic lesions did not form. Uterine endometrial tissue forms endometriotic lesions, whereas tissues with differing basal expression levels of estrogen receptor alpha (ESR1) and estrogen receptor beta (ESR2), similar cellular composition to uterus (i.e. bladder, mammary gland, and lung), and treated with estradiol did not form lesions. As MMP7 is known to play a major role in the organization/reorganization of the endometrium during the menstrual cycle, blocking metalloproteinase (MMP) activity significantly decreased the invasive properties of these cells. Together, these findings suggest that endometriosis is immune and uterine specific and that MMP7 likely plays a role in the ability of uterine tissue and the innate immune system to establish and maintain endometriotic lesions.

Celecoxib significantly reduces opioid use after shoulder arthroplasty

BACKGROUND

The opioid crisis has illuminated the risks of opioid use for pain management, with renewed interest in reducing opioid consumption after common orthopedic procedures. Anti-inflammatory medication is an important component of multimodal pain management for patients undergoing orthopedic surgery. The purpose of this study was to evaluate the effect of celecoxib on pain control and opioid use after shoulder surgery.

METHODS

Patients scheduled for either total shoulder replacement (group 1) or rotator cuff repair (group 2) were candidates for the study. The exclusion criteria included allergy to celecoxib, coagulopathy, use of anticoagulants, baseline use of long-acting opioids, and a history of medical conditions such as myocardial infarction or stroke. Consenting patients were randomized by type of procedure using block randomization to receive either placebo or celecoxib 1 hour prior to the procedure and for 3 weeks postoperatively. The primary outcome measure assessed was opioid utilization as measured by morphine-equivalent dose (MED). Secondary outcome measures included pain scores at 3 and 6 weeks postoperatively. Data were analyzed using multiple linear regression.

RESULTS

Of 1081 patients scheduled for either total shoulder replacement or rotator cuff repair from February 2014 to February 2018, 78 were enrolled for arthroplasty (group 1, with 39 receiving celecoxib and 39 receiving placebo) and 79 were enrolled for rotator cuff repair (group 2, with 40 receiving celecoxib and 39 receiving placebo). Compared with the placebo arm, patients prescribed celecoxib took fewer MEDs by -168 (95% confidence interval [CI], -272 to -64; P < .01) at 3 weeks in the total population and by -197.7 (95% CI, -358 to -38; P = .02) in the arthroplasty group. Similarly, at 6 weeks, total MEDs used was -199 (95% CI, -356 to -42; P < .01) in the total population and -270 (95% CI, -524 to -16; P = .04) in the arthroplasty group. No statistically significant differences in opioid consumption were found between study arms in the cuff repair group, at either 3 or 6 weeks. Of note, preoperative opioid use was statistically associated with higher levels of opioid use in the total population and group 1 at 3 and 6 weeks (P < .01 for all) but not in group 2 (P > .05 for both).

CONCLUSIONS

Use of morphine equivalents was statistically significantly less at 3 and 6 weeks in patients who took celecoxib in the total population and in the arthroplasty group. Patients prescribed celecoxib for 3 weeks after shoulder surgery took less opioid medication for pain at 3 and 6 weeks. Multimodal pain control using celecoxib is an effective way to reduce postoperative opioid use in shoulder arthroplasty patients. Preoperative opioid use is associated with higher levels of opioid use after shoulder arthroplasty.

Healing rates after rotator cuff repair for patients taking either celecoxib or placebo: a double-blind randomized controlled trial

Background

Use of anti-inflammatory medications (NSAIDs) is an important component of multimodal pain control after orthopedic procedures to avoid opioid overutilization and abuse. However, the deleterious effects of NSAIDs on tendon healing are of particular concern in rotator cuff repair (RCR). The purpose of this study was to evaluate the effect of celecoxib or placebo on healing rates after RCR when administered in the perioperative and immediate postoperative period using MRI evaluation at one year postoperatively. A secondary aim was to determine whether clinical differences existed between patients with intact or non-intact repairs.

Methods

Patients aged ≤65 years with partial- or full-thickness rotator cuff tear (<25x25 mm) were randomized to receive celecoxib 400 mg or placebo 1 hour before the procedure and 200mg bid for 3 weeks postoperatively. All patients were treated as clinically indicated at the time of surgery and followed standard postoperative protocol. Repair integrity was evaluated with MRI using the Sugaya classification for repair integrity. Data were analyzed using multivariable logistic regression by intent to treat.

Results

Seventy-nine patients were enrolled; 21 were lost to follow-up, 6 did not have cuff repair, 5 were revised, and 2 declined follow-up, leaving 45 patients with one-year follow-up. Five of these patients did not complete MRI, leaving 40 patients for review. Eighteen of 20 patients (90%) who received celecoxib completed all doses of study medication as did 15 of 20 patients (75%) who received placebo. The patient groups were similar for demographics, clinical results, and healing rate. After adjusting for tear size, no statistically significant difference in healing rate was found between groups, with 10 of 20 celecoxib patients (50%) having intact repair at 1 year compared with 14 of 20 placebo patients (70%) (OR = 0.53, 95% CI: 0.14, 2.08, P = 0.35).

Conclusion

Half of the patients who received celecoxib had an intact repair compared with 70% intact repair for patients receiving placebo. Although not statistically significant in this small study, larger studies are needed to clarify this important clinical concern. The authors do not recommend use of celecoxib for postoperative pain control after RCR.

Comparability of the small RNA secretome across human biofluids concomitantly collected from healthy adults

Small extracellular vesicles (sEV) are nano-sized (40–150 nm), membrane-encapsulated vesicles that are released by essentially all cells into the extracellular space and function as intercellular signaling vectors through the horizontal transfer of biologic molecules, including microRNA (miRNA) and other small non-coding RNA (ncRNA), that can alter the phenotype of recipient cells. sEV are present in essentially all extracellular biofluids, including serum, urine and saliva, and offer a new avenue for discovery and development of novel biomarkers of various disease states and exposures. The objective of this study was to systematically interrogate similarities and differences between sEV ncRNA derived from saliva, serum and urine, as well as cell-free small ncRNA (cf-ncRNA) from serum. Saliva, urine and serum were concomitantly collected from 4 healthy donors to mitigate potential bias that can stem from interpersonal and temporal variability. sEV were isolated from each respective biofluid, along with cf-RNA from serum. sEV were isolated from the respective biofluids via differential ultracentrifugation with a 30% sucrose cushion to minimize protein contamination. Small RNA-sequencing was performed on each sample, and cluster analysis was performed based on ncRNA profiles. While some similarities existed in terms of sEV ncRNA cargo across biofluids, there are also notable differences in ncRNA class and ncRNA secretion, with sEV in each biofluid bearing a unique ncRNA profile, including major differences in composition by ncRNA class. We conclude that sEV ncRNA cargo varies according to biofluid, so thus should be carefully selected and interpreted when designing or contrasting translational or epidemiological studies.

Rotator Cuff Repair With Knotless Technique Is Quicker and More Cost-Effective Than Knotted Technique

Purpose

To determine the cost-effectiveness of knotted (KT) versus knotless (KL) methods for rotator cuff surgical repair and to assess differences in patients' outcomes.

Methods

We retrospectively identified all patients who underwent arthroscopic rotator cuff repair at 1 institution by 1 surgeon over 2 6-month periods of time (KT technique from August 1, 2013, through January 31, 2014; and KL technique from December 1, 2014, through May 31, 2015) to calculate the direct and indirect costs associated with arthroscopic KT or KL suture bridge rotator cuff repair. Patient demographics, number of anchors used, tendons repaired, procedure time, operative time, and clinical results were also evaluated. We used univariate generalized linear models with a Gaussian distribution for assessment scores and total and implant cost data.

Results

We identified 87 patients for inclusion during the 2 time frames (35 KT, 54 KL). After excluding patients for tear size < 4 cm² (n = 42), ≤ 3 anchors (n = 5), revision surgery (n = 1), and those in whom additional procedures were performed (n = 2), 37 eligible subjects remained (n_KT = 15, n_KL = 22). Median implant costs were statistically significantly higher in the KL group than in the KT group (M_KL = $2,127, M_KT = $1,520, β = 413.7, 95% CI: 242.8, 584.6, P < .01), and more anchors were used in the KL group, with KT requiring a median of 4 anchors (IQR: 4, 5) and KL requiring a median of 5 anchors (IQR: 5, 5, P = .02). Procedure time was cut in half with KL repair (estimated 43.5 minutes) versus KT repair (80 minutes) (β = 0.5, 95% CI: 0.4, 0.6, P < .001). Operating room time also was reduced by approximately 40% (79.5 minutes for KL; 121 minutes for KT [β = 0.6, CI: 0.6, 0.7, P < .001]). Once operating room costs were considered, median costs were found to be significantly lower in the KL group (M_KL = $3788.40, M_KT = $4262.90, β = -492.1, 95% CI: -840.0, -144.1, P < .01). No statistically significant differences were found between groups in mean preoperative, postoperative or postpreoperative differences in the visual analog scale, Simple Shoulder Test, American Shoulder and Elbow Surgeons, or University of California at Los Angeles scores (P > 0.05 for all).

Conclusions

Despite using more anchors and incurring higher implant costs, the KL technique for rotator cuff repair required less surgical procedure time and cost less overall than the KT technique and resulted in equivalent clinical results.

Level of Evidence

Level IV Economic and Decision Analyses.

Elevated serum chemokines are independently associated with both endometriosis and uranium exposure

Endometriosis is a complex disease impacted by the hormonal and immune systems. Cytokines and chemokines are serum biomarkers that maybe useful to develop a noninvasive disease diagnosis. Individuals in the Fernald Community Cohort were exposed to uranium, a heavy metal with radioactive properties and estrogenic potential; therefore, serum samples from women in this cohort with or without uranium and with or without endometriosis were compared for alterations in chemokine, cytokine, and matrix metalloproteinase (MMP) levels. Control women were matched to endometriosis cases by uranium exposure, age, and body mass index. MMP levels were not altered. Five chemokines and one cytokine significantly increased in endometriosis cases versus controls irrespective of uranium exposure. Uranium exposure alone was associated with an increase in inflammatory chemokines. The majority of the elevated chemokines in endometriosis cases play important roles in attracting T helper-2 cells, which may be vital to understanding the immune response in endometriosis.

Use of a Mouse Model of Experimentally Induced Endometriosis to Evaluate and Compare the Effects of Bisphenol A and Bisphenol AF Exposure

BACKGROUND

Endometriosis is a gynecological disease affecting 1 in 10 women of reproductive age. Endometriosis incidence has risen; however, whether this rise is due to disease awareness or environmental contamination is not known.

OBJECTIVE

The objective of this study was to determine if bisphenol A (BPA) or bisphenol AF (BPAF) potentiate the development of endometriosis and if hormonal status alters how toxicant exposure affects disease.

METHODS

A mouse model of endometriosis, where minced uterine tissue is injected into the peritoneal cavity of a host mouse, was used to examine the effects of BPA and BPAF on endometriosis lesion development in ovariectomized and hormonally intact mice. BPA and BPAF were delivered through diet to include no-observed-adverse-effect-level (NOAEL) and the low-observed-adverse-effect-level (LOAEL) exposure levels. After six weeks (at necropsy), lesions, ovaries, and blood were collected to examine characteristics, gene expression, and hormonal regulation.

RESULTS

BPA and BPAF treatments affected endometriosis in a manner specific to dose and hormonal status of the host mouse. Estrogen and endometriosis-mediated differences in lesion target gene expression also depended on hormonal status. In intact mice, ovarian steroidogenic pathways were disrupted, progesterone levels were lowered, and atretic oocyte numbers were higher with toxicant exposure. BPAF, more so than BPA, resulted in more endometriosis lesion growth, but both toxicants disrupted normal ovarian signaling.

CONCLUSION

These findings further our understanding of the effects and hormonal impacts of BPA and BPAF on endometriosis perturbation in ovariectomized and hormonally intact mice. BPAF appeared to be similar if not more estrogenic than BPA and may be affecting an environmental contribution of the increased incidence of endometriosis. https://doi.org/10.1289/EHP3802.

Differential in Vitro Biological Action, Coregulator Interactions, and Molecular Dynamic Analysis of Bisphenol A (BPA), BPAF, and BPS Ligand-ERα Complexes

BACKGROUND

Bisphenol A (BPA) is an endocrine-disrupting chemical (EDC) that might be harmful to human health. Recently, there has been widespread usage of bisphenol chemicals (BPs), such as bisphenol AF (BPAF) and bisphenol S (BPS), as replacements for BPA. However, the potential biological actions, toxicity, and the molecular mechanism of these compounds are still poorly understood.

OBJECTIVES

Our objective was to examine the estrogenic effects of BPA, BPAF, and BPS and the molecular mechanisms of action in the estrogen receptor alpha (ERα) complex.

METHODS

In vitro cell models were used to compare the estrogenic effects of BPA, BPAF, and BPS to estrogen. Microarray Assay for Real-Time Coregulator-Nuclear receptor Interaction (MARCoNI) analysis was used to identify coregulators of BPA, BPAF, and BPS, and molecular dynamic (MD) simulations were used to determine the compounds binding in the ERα complex.

RESULTS

We demonstrated that BPA and BPAF have agonistic activity for both ERα and ERβ, but BPS has ERα-selective specificity. We concluded that coregulators were differentially recruited in the presence of BPA, BPAF, or BPS. Interestingly, BPS recruited more corepressors when compared to BPA and BPAF. From a series of MD analysis, we concluded that BPA, BPAF, and BPS can bind to the ER-ligand-binding domain with differing energetics and conformations. In addition, the binding surface of coregulator interactions on ERα was characterized for the BPA, BPAF, and BPS complexes.

CONCLUSION

These findings further our understanding of the molecular mechanisms of EDCs, such as BPs, in ER-mediated transcriptional activation, biological activity, and their effects on physiological functions in human health. https://doi.org/10.1289/EHP2505.

Early Endometriosis in Females Is Directed by Immune-Mediated Estrogen Receptor α and IL-6 Cross-Talk

Endometriosis is a gynecological disease that negatively affects the health of 1 in 10 women. Although more information is known about late stage disease, the early initiation of endometriosis and lesion development is poorly understood. Herein, we use a uterine tissue transfer mouse model of endometriosis to examine early disease development and its dependence on estradiol (E2) and estrogen receptor (ER) α within 72 hours of disease initiation. Using wild-type and ERα knockout mice as hosts or donors, we find substantial infiltration of neutrophils and macrophages into the peritoneal cavity. Examining cell infiltration, lesion gene expression, and peritoneal fluid, we find that E2/ERα plays a minor role in early lesion development. Immune-mediated signaling predominates E2-mediated signaling, but 48 hours after the initiation of disease, a blunted interleukin (IL)-6-mediated response is found in developing lesions lacking ERα. Our data provide evidence that the early initiation of endometriosis is predominantly dependent on the immune system, whereas E2/ERα/IL-6-mediated cross-talk plays a partial role. These findings suggest there are two phases of endometriosis-an immune-dependent phase and a hormone-dependent phase, and that targeting the innate immune system could prevent lesion attachment in this susceptible population of women.

The Montara Oil Spill: A 2009 Well Blowout in the Timor Sea

A well on the Montara platform on the Australian continental shelf blew out in August 2009 and spilled oil into the Timor Sea for 74 days. The oil, estimated at as much as 23.5 million L in total volume, spread over a large area of the shelf and eventually into Indonesian waters. This paper documents, through published literature, reports of both Australian and Indonesian governments and observations of coastal residents and fishermen the spread of the oil and attempts to estimate its impact. The lack of observers on the ocean and baseline, pre-spill data on populations of marine organisms, and delays in deploying scientific surveys after the spill severely limited efforts by the Australian government to determine damage in its territorial waters. Biological survey work was not done in Indonesian waters, but coastal residents attested to relatively severe impacts to algal farms. In addition fish landings declined in one port in southwest Timor Island.

Biliverdin Reductase A Attenuates Hepatic Steatosis by Inhibition of Glycogen Synthase Kinase (GSK) 3β Phosphorylation of Serine 73 of Peroxisome Proliferator-activated Receptor (PPAR) α

Non-alcoholic fatty liver disease is the most rapidly growing form of liver disease and if left untreated can result in non-alcoholic steatohepatitis, ultimately resulting in liver cirrhosis and failure. Biliverdin reductase A (BVRA) is a multifunctioning protein primarily responsible for the reduction of biliverdin to bilirubin. Also, BVRA functions as a kinase and transcription factor, regulating several cellular functions. We report here that liver BVRA protects against hepatic steatosis by inhibiting glycogen synthase kinase 3β (GSK3β) by enhancing serine 9 phosphorylation, which inhibits its activity. We show that GSK3β phosphorylates serine 73 (Ser(P)⁷³) of the peroxisome proliferator-activated receptor α (PPARα), which in turn increased ubiquitination and protein turnover, as well as decreased activity. Interestingly, liver-specific BVRA KO mice had increased GSK3β activity and Ser(P)⁷³ of PPARα, which resulted in decreased PPARα protein and activity. Furthermore, the liver-specific BVRA KO mice exhibited increased plasma glucose and insulin levels and decreased glycogen storage, which may be due to the manifestation of hepatic steatosis observed in the mice. These findings reveal a novel BVRA-GSKβ-PPARα axis that regulates hepatic lipid metabolism and may provide unique targets for the treatment of non-alcoholic fatty liver disease.

Endometriosis: where are we and where are we going?

Endometriosis currently affects ~5.5 million reproductive-aged women in the U.S. with symptoms such as painful periods (dysmenorrhea), chronic pelvic pain, pain with intercourse (dyspareunia), and infertility. It is defined as the presence of endometrial tissue outside the uterine cavity and is found predominately attached to sites within the peritoneal cavity. Diagnosis for endometriosis is solely made through surgery as no consistent biomarkers for disease diagnosis exist. There is no cure for endometriosis and treatments only target symptoms and not the underlying mechanism(s) of disease. The nature of individual predisposing factors or inherent defects in the endometrium, immune system, and/or peritoneal cavity of women with endometriosis remains unclear. The literature over the last 5 years (2010-2015) has advanced our critical knowledge related to hormones, hormone receptors, immune dysregulation, hormonal treatments, and the transformation of endometriosis to ovarian cancer. In this review, we cover the aforementioned topics with the goal of providing the reader an overview and related references for further study to highlight the progress made in endometriosis research, while concluding with critical areas of endometriosis research that are urgently needed.

Secondary ion mass spectrometry signatures for verifying declarations of fissile-material production

Direct analysis of uranium enrichment facility components were performed using secondary ion mass spectrometry (SIMS). A standard protocol was developed to enable preparation of SIMS samples from a corroded pipe piece without disturbing the corrosion layer. Unique uranium, oxygen and fluorine containing signatures were discovered in the corrosion layer by performing a mass scan of the region of interest from 230 to 280amu. These signatures identified the source of the corrosion layer as uranium hexafluoride (UF6) or an associated hydrolysis product. Isotopic analysis of the corrosion layer determined enrichment of (235)U to a value of 0.0116±0.0019 for the (235)U/(238)U isotopic ratio as compared to the NIST traceable standard (CRM 112-A) with a natural (235)U/(238)U isotopic ratio of 0.007254±0.000004. SIMS depth analysis revealed that the corrosion layer was isotopically homogenous to a depth of ~23.5µm. Optical profilometry measurements prior to and following SIMS depth analysis were used to determine a sputter rate of 0.48nm/s for 18.5keV O(-) ion bombardment of the corrosion layer. The data presented is conclusive evidence that SIMS depth analysis can be used to identify novel nuclear archeology signatures from uranium enrichment components and perform meaningful isotopic analysis of these signatures.

Endometrial CXCL13 expression is cycle regulated in humans and aberrantly expressed in humans and Rhesus macaques with endometriosis

C-X-C ligand 13 (CXCL13), a regulator of mucosal immunity, is secreted by human endometrial epithelium and may be involved in embryo implantation. However, cyclic expression of human endometrial CXCL13 in health and disease is not well studied. This study examines cycle stage-specific endometrial CXCL13 expression in normal humans when compared to those with biopsy-confirmed, stage 1 to 4 endometriosis using real-time reverse transcriptase, real-time polymerase chain reaction and immunohistochemistry. Eutopic endometrial CXCL13 expression was also compared between normal, control Rhesus macaques, and macaques with advanced endometriosis. In healthy women, CXLC13 messenger RNA expression was minimal in the proliferative phase and maximal in the secretory phase. However, in the presence of endometriosis, proliferative-phase endometrial expression markedly increased in both humans and rhesus subjects (P < .05). The cross-species and cross-stage concordance suggests a pathophysiologic role for CXCL13 in endometriosis and its use as a biomarker for disease.

Research resource: comparison of gene profiles from wild-type ERα and ERα hinge region mutants

We showed previously that the hinge region of estrogen receptor (ER) α is involved in mediating its actions. The hinge 1 (H1) ERα mutant has disrupted nuclear localization and has lost interaction with c-JUN, but retains estrogen response element (ERE)-mediated functions. The hinge 2 + nuclear export sequence (H2NES) ERα mutant does not maintain nuclear translocation with hormone and no longer activates ERE target genes but does retain a nongenomic, nonnuclear, rapid-action response. Herein, we used the human endometrial cancer Ishikawa stable cell lines (Ishikawa/vector, Ishikawa/wild-type [WT] ERα, Ishikawa/H1 ERα, or Ishikawa/H2NES ERα) to characterize the biological activities of these 2 ERα hinge region mutants. We confirmed by confocal microscopy increased cytoplasmic ERα in the H1 ERα cell line and full cytoplasmic ERα localization in the H2NES ERα cell line. Luciferase assays using the 3xERE reporter showed activation of H1 ERα and H2NES ERα by estradiol (E2) treatment, but using the endogenous pS2 reporter, luciferase activity was only seen with the H1 ERα cell line. Examining cell proliferation revealed that only the WT ERα and H1 ERα cell lines increased proliferation after treatment. Using microarrays, we found that WT ERα and H1 ERα cluster together, whereas vector and H2NES ERα are most similar and cluster independently of E2 treatment. These studies revealed that the nongenomic activities of ERα are unable to mediate proliferative changes or the transcriptional profile after treatment and demonstrate the importance of genomic action for ERα/E2-mediated responses with the nongenomic actions of ERα being complementary to elicit the full biological actions of ERα.

Diethylstilbestrol (DES)-stimulated hormonal toxicity is mediated by ERα alteration of target gene methylation patterns and epigenetic modifiers (DNMT3A, MBD2, and HDAC2) in the mouse seminal vesicle

BACKGROUND

Diethylstilbestrol (DES) is a synthetic estrogen associated with adverse effects on reproductive organs. DES-induced toxicity of the mouse seminal vesicle (SV) is mediated by estrogen receptor α (ERα), which alters expression of seminal vesicle secretory protein IV (Svs4) and lactoferrin (Ltf) genes.

OBJECTIVES

We examined a role for nuclear receptor activity in association with DNA methylation and altered gene expression.

METHODS

We used the neonatal DES exposure mouse model to examine DNA methylation patterns via bisulfite conversion sequencing in SVs of wild-type (WT) and ERα-knockout (αERKO) mice.

RESULTS

The DNA methylation status at four specific CpGs (-160, -237, -306, and -367) in the Svs4 gene promoter changed during mouse development from methylated to unmethylated, and DES prevented this change at 10 weeks of age in WT SV. At two specific CpGs (-449 and -459) of the Ltf gene promoter, DES altered the methylation status from methylated to unmethylated. Alterations in DNA methylation of Svs4 and Ltf were not observed in αERKO SVs, suggesting that changes of methylation status at these CpGs are ERα dependent. The methylation status was associated with the level of gene expression. In addition, gene expression of three epigenetic modifiers-DNMT3A, MBD2, and HDAC2-increased in the SV of DES-exposed WT mice.

CONCLUSION

DES-induced hormonal toxicity resulted from altered gene expression of Svs4 and Ltf associated with changes in DNA methylation that were mediated by ERα. Alterations in gene expression of DNMT3A, MBD2, and HDAC2 in DES-exposed male mice may be involved in mediating the changes in methylation status in the SV.

CITATION

Li Y, Hamilton KJ, Lai AY, Burns KA, Li L, Wade PA, Korach KS. 2014. Diethylstilbestrol (DES)-stimulated hormonal toxicity is mediated by ERα alteration of target gene methylation patterns and epigenetic modifiers (DNMT3A, MBD2, and HDAC2) in the mouse seminal vesicle. Environ Health Perspect 122:262-268; http://dx.doi.org/10.1289/ehp.1307351.

The naturally occurring luteinizing hormone surge is diminished in mice lacking estrogen receptor Beta in the ovary

Female ESR2-null mice (betaERKO) display defects in ovarian function and are subfertile. Follicular maturation is impaired and explains smaller litters, but betaERKO also produce fewer litters, which may be partially due to inadequate ovulatory signals. To test this, the amplitude and timing of the naturally occurring luteinizing hormone (LH) surge was measured in individual intact betaERKO and wild-type (WT) mice. Vaginal cytology was evaluated daily, and blood samples were taken from mice in proestrus. The amplitude of the LH surge was severely blunted in betaERKO mice compared to WT, but pituitary LH levels revealed no differences. The betaERKO mice did not produce a preovulatory estradiol surge. To determine if the smaller LH surges and the reduced number of litters in betaERKO were due to the lack of ESR2 in the hypothalamic-pituitary axis or due to the absence of ESR2 in the ovary, ovaries were transplanted from WT into betaERKO mice and vice versa. The size of the LH surge was reduced only in mice lacking ESR2 within the ovary, and these mice had fewer litters. Fertility and size of the LH surge were rescued in betaERKO mice receiving a WT ovary. These data provide the first experimental evidence that the LH surge is impaired in betaERKO females and may contribute to their reduced fertility. ESR2 is not necessary within the pituitary and hypothalamus for the generation of a normal LH surge and for normal fertility, but ESR2 is essential within the ovary to provide proper signals.

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.

Endocrine-Disrupting Chemicals (EDCs): In Vitro Mechanism of Estrogenic Activation and Differential Effects on ER Target Genes

BACKGROUND

Endocrine-disrupting chemicals (EDCs) influence the activity of estrogen receptors (ERs) and alter the function of the endocrine system. However, the diversity of EDC effects and mechanisms of action are poorly understood.

OBJECTIVES

We examined the agonistic activity of EDCs through ERα and ERβ. We also investigated the effects of EDCs on ER-mediated target genes.

METHODS

HepG2 and HeLa cells were used to determine the agonistic activity of EDCs on ERα and ERβ via the luciferase reporter assay. Ishikawa cells stably expressing ERα were used to determine changes in endogenous ER target gene expression by EDCs.

RESULTS

Twelve EDCs were categorized into three groups on the basis of product class and similarity of chemical structure. As shown by luciferase reporter analysis, the EDCs act as ER agonists in a cell type- and promoter-specific manner. Bisphenol A, bisphenol AF, and 2-2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (group 1) strongly activated ERα estrogen responsive element (ERE)-mediated responses. Daidzein, genistein, kaempferol, and coumestrol (group 2) activated both ERα and ERβ ERE-mediated activities. Endosulfan and kepone (group 3) weakly activated ERα. Only a few EDCs significantly activated the "tethered" mechanism via ERα or ERβ. Results of real-time polymerase chain reaction indicated that bisphenol A and bisphenol AF consistently activated endogenous ER target genes, but the activities of other EDCs on changes of ER target gene expression were compound specific.

CONCLUSION

Although EDCs with similar chemical structures (in the same group) tended to have comparable ERα and ERβ ERE-mediated activities, similar chemical structure did not correlate with previously reported ligand binding affinities of the EDCs. Using ERα-stable cells, we observed that EDCs differentially induced activity of endogenous ER target genes.

The natural estrogenic compound diarylheptanoid (D3): in vitro mechanisms of action and in vivo uterine responses via estrogen receptor α

BACKGROUND

Diarylheptanoid (D3) isolated from the medicinal plant, Curcuma comosa, has estrogenic activity.

OBJECTIVE

We aimed to elucidate the mechanism(s) of D3 action and compare it with that of 17β-estradiol (E2) using both in vitro and in vivo uterine models.

METHODS

We used human uterine (Ishikawa) cells to determine the estrogenic action of D3 on the activation and nuclear translocation of estrogen receptor α (ERα). In addition, we further characterized the uterine response to D3 treatment in vivo.

RESULTS

D3 activated an estrogen responsive element (ERE) luciferase reporter through ERα, and molecular modeling suggested that D3 could be accommodated in the ERα binding pocket. Using modified ERα to assay ligand-dependent nuclear translocation, we observed D3-dependent ERα interaction and translocation. In mouse uteri, early- and late-phase estrogen-regulated gene responses were increased in D3-treated ovariectomized wild-type animals, in a manner similar to that of E2; no response was seen in ERα knockout animals. We observed a divergence in estrogen responses after D3 treatment: D3 induced robust DNA synthesis in uterine epithelial cells, linked to an increase in cell-cycle-related genes; however, no increase in uterine weight was observed 24 hr after treatment. D3 also affected uterine progesterone receptor expression patterns similar to E2. When D3 and E2 were administered together, we observed no additive or antagonistic effects of D3 on E2. Our findings suggest that D3 is a weak estrogenic agonist compound.

CONCLUSION

D3 is a weakly acting phytoestrogen that mimics the mitogenic responses produced by E2 in an ERα-dependent manner, but it is unable to increase uterine weight or enhance or antagonize the effects of estrogen.

Role of estrogen receptor signaling required for endometriosis-like lesion establishment in a mouse model

Endometriosis results from ectopic invasion of endometrial tissue within the peritoneal cavity. Aberrant levels of the estrogen receptor (ER), ERα and ERβ, and higher incidence of autoimmune disorders are observed in women with endometriosis. An immunocompetent mouse model of endometriosis was used in which minced uterine tissue from a donor was dispersed into the peritoneal cavity of a recipient. Wild-type (WT), ERα-knockout (αERKO), and βERKO mice were donors or recipients to investigate the roles of ERα, ERβ, and estradiol-mediated signaling on endometriosis-like disease. Mice were treated with vehicle or estradiol, and resulting location, number, and size of endometriosis-like lesions were assessed. In comparison with WT lesions in WT hosts, αERKO lesions in WT hosts were smaller and fewer in number. The effect of ER status and estradiol treatment on nuclear receptor status, proliferation, organization, and inflammation within lesions were examined. αERKO lesions in WT hosts did not form distal to the incision site, respond to estradiol, or proliferate but did have increased inflammation. WT lesions in αERKO hosts did respond to estradiol, proliferate, and show decreased inflammation with treatment, but surprisingly, progesterone receptor expression and localization remained unchanged. Only minor differences were observed between WT lesions in βERKO hosts and βERKO lesions in WT hosts, demonstrating the estradiol-mediated signaling responses are predominately through ERα. In sum, these results suggest ER in both endometriosis-like lesions and their environment influence lesion characteristics, and understanding these interactions may play a critical role in elucidating this enigmatic disease.

Differential estrogenic actions of endocrine-disrupting chemicals bisphenol A, bisphenol AF, and zearalenone through estrogen receptor α and β in vitro

BACKGROUND

Endocrine-disrupting chemicals (EDCs) are widely found in the environment. Estrogen-like activity is attributed to EDCs, such as bisphenol A (BPA), bisphenol AF (BPAF), and zearalenone (Zea), but mechanisms of action and diversity of effects are poorly understood.

OBJECTIVES

We used in vitro models to evaluate the mechanistic actions of BPA, BPAF, and Zea on estrogen receptor (ER) α and ERβ.

METHODS

We used three human cell lines (Ishikawa, HeLa, and HepG2) representing three cell types to evaluate the estrogen promoter activity of BPA, BPAF, and Zea on ERα and ERβ. Ishikawa/ERα stable cells were used to determine changes in estrogen response element (ERE)-mediated target gene expression or rapid action-mediated effects.

RESULTS

The three EDCs showed strong estrogenic activity as agonists for ERα in a dose-dependent manner. At lower concentrations, BPA acted as an antagonist for ERα in Ishikawa cells and BPAF acted as an antagonist for ERβ in HeLa cells, whereas Zea was only a partial antagonist for ERα. ERE-mediated activation by BPA and BPAF was via the AF-2 function of ERα, but Zea activated via both the AF-1 and AF-2 functions. Endogenous ERα target genes and rapid signaling via the p44/42 MAPK pathway were activated by BPA, BPAF, and Zea.

CONCLUSION

BPA and BPAF can function as EDCs by acting as cell type-specific agonists (≥ 10 nM) or antagonists (≤ 10 nM) for ERα and ERβ. Zea had strong estrogenic activity and activated both the AF-1 and AF-2 functions of ERα. In addition, all three compounds induced the rapid action-mediated response for ERα.

Estrogen receptors and human disease: an update

A myriad of physiological processes in mammals are influenced by estrogens and the estrogen receptors (ERs), ERα and ERβ. As we reviewed previously, given the widespread role for estrogen in normal human physiology, it is not surprising that estrogen is implicated in the development or progression of a number of diseases. In this review, we are giving a 5-year update of the literature regarding the influence of estrogens on a number of human cancers (breast, ovarian, colorectal, prostate, and endometrial), endometriosis, fibroids, and cardiovascular disease. A large number of sophisticated experimental studies have provided insights into human disease, but for this review, the literature citations were limited to articles published after our previous review (Deroo and Korach in J Clin Invest 116(3):561-570, 2006) and will focus in most cases on human data and clinical trials. We will describe the influence in which estrogen's action, through one of or both of the ERs, mediates the aforementioned human disease states.

Selective mutations in estrogen receptor alpha D-domain alters nuclear translocation and non-estrogen response element gene regulatory mechanisms

The three main mechanisms of ERα action are: 1) nuclear, genomic, direct DNA binding, 2) nuclear, genomic, "tethered"-mediated, protein-protein interactions, and 3) non-nuclear, non-genomic, rapid action responses. Reports suggest the D-domain or hinge region of ERα plays an important role in mechanisms 1 and 2 above. Studies demonstrating the functionality of the ERα hinge region have resected the full D-domain; therefore, site directed mutations were made to attribute precise sequence functionality to this domain. This study focuses on the characterization and properties of three novel site directed ERα- D-domain mutants. The Hinge 1 (H1) ERα mutant has disrupted nuclear localization, can no longer perform tethered mediated responses and has lost interaction with c-Jun, but retains estrogen response element (ERE)-mediated functions as demonstrated by confocal microscopy, reporter assays, endogenous gene expression and co-immunoprecipitation. The H2 ERα mutant is non-nuclear, but translocates to the nucleus with estradiol (E2) treatment and maintains ERE-mediated functionality. The H2+NES ERα mutant does not maintain nuclear translocation with hormone binding, no longer activates ERE-target genes, functions in ERE- or tethered-mediated luciferase assays, but does retain the non-genomic, non-nuclear, rapid action response. These studies reveal the sequence(s) in the ERα hinge region that are involved in tethered-mediated actions as well as nuclear localization and attribute important functionality to this region of the receptor. In addition, the properties of these ERα mutants will allow future studies to further dissect and characterize the three main ERα mechanisms of action and determine the mechanistic role each action has in estrogen hormone regulation.

Insufficient luteinizing hormone-induced intracellular signaling disrupts ovulation in preovulatory follicles lacking estrogen receptor-{beta}

Gonadotropin-stimulated estrogen receptor-beta (ERbeta)-null preovulatory follicles exhibit submaximal estradiol production, insufficient acquisition of LH receptor, and attenuated expression of essential ovulatory genes. These observations lead to low ovulatory rates compared with wild-type (WT) follicles. We hypothesize that insufficient LH receptor results in reduced cAMP production after an ovulatory stimulus. Individual preantral follicles were cultured with FSH for 4 d and then induced to ovulate with a single dose of human chorionic gonadotropin (hCG). cAMP levels 1 h after hCG were 50% lower in ERbeta-null than WT follicles. To determine whether the lack of LH receptor, and resulting lack of cAMP, could be bypassed by direct activation of adenylyl cyclase, WT and ERbeta-null follicles were induced to ovulate with forskolin. Ten micromolar forskolin doubled the ovulatory rate of ERbeta-null follicles compared with treatment with hCG ( approximately 50 vs. 25%, respectively). In WT follicles, 10 microm forskolin reduced the ovulation rate compared with hCG (14 vs. 83%, respectively), indicating that high doses of forskolin inhibited WT ovulation. A 10 microm concentration of forskolin induced cAMP levels in ERbeta-null follicles that were comparable to levels produced in WT follicles after hCG and either partially or completely rescued the attenuated expression of LH-responsive genes. These data indicate that direct activation of adenylyl cyclase, resulting in increased production of cAMP, partially rescues the ovulatory response of ERbeta-null follicles, suggesting that insufficient LH receptor and low cAMP levels contribute to their poor ovulatory rates. We also determined that ERbeta-null ovaries exhibit an alteration in the activation of ERK1/2. Our evaluation of the ERbeta-null ovarian phenotype indicates that ERbeta plays a role in facilitating folliculogenesis. We show that expression of ERbeta in preovulatory follicles is required for adequate cAMP production and propose that an optimal level of cAMP is required for hCG-stimulated ovulation.

Modulation of PPAR activity via phosphorylation

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of transcription factors that respond to specific ligands by altering gene expression in a cell-, developmental- and sex-specific manner. Three subtypes of this receptor have been discovered (PPARalpha, beta and gamma), each apparently evolving to fulfill different biological niches. PPARs control a variety of target genes involved in lipid homeostasis, diabetes and cancer. Similar to other nuclear receptors, the PPARs are phosphoproteins and their transcriptional activity is affected by cross-talk with kinases and phosphatases. Phosphorylation by the mitogen-activated protein kinases (ERK- and p38-MAPK), Protein Kinase A and C (PKA, PKC), AMP Kinase (AMPK) and glycogen synthase kinase-3 (GSK3) affect their activity in a ligand-dependent or -independent manner. The effects of phosphorylation depend on the cellular context, receptor subtype and residue metabolized which can be manifested at several steps in the PPAR activation sequence including ligand affinity, DNA binding, coactivator recruitment and proteasomal degradation. The review will summarize the known PPAR kinases that directly act on these receptors, the sites affected and the result of this modification on receptor activity.

Rotator cuff muscle architecture: implications for glenohumeral stability

We examined the architectural properties of the rotator cuff muscles in 10 cadaveric specimens to understand their functional design. Based on our data and previously published joint angle-muscle excursion data, sarcomere length operating ranges were modeled through all permutations in 75 masculine medial and lateral rotation and 75 masculine abduction at the glenohumeral joint. Based on physiologic cross-sectional area, the subscapularis would have the greatest force-producing capacity, followed by the infraspinatus, supraspinatus, and teres minor. Based on fiber length, the supraspinatus would operate over the widest range of sarcomere lengths. The supraspinatus and infraspinatus had relatively long sarcomere lengths in the anatomic position, and were under relatively high passive tensions at rest, indicating they are responsible for glenohumeral resting stability. However, the subscapularis contributed passive tension at maximum abduction and lateral rotation, indicating it plays a critical role in glenohumeral stability in the position of apprehension. These data illustrate the exquisite coupling of muscle architecture and joint mechanics, which allows the rotator cuff to produce near maximal active tensions in the midrange and produce passive tensions in the various end-range positions. During surgery relatively small changes to rotator cuff muscle length may result in relatively large changes in shoulder function.

Regulation of Peroxisome Proliferator-Activated Receptor α by Protein Kinase C

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a nuclear receptor activated by fatty acids, hypolipidemic drugs, and peroxisome proliferators (PPs). Like other nuclear receptors, PPARalpha is a phosphoprotein whose activity is affected by a variety of growth factor signaling cascades. In this study, the effects of protein kinase C (PKC) on PPARalpha activity were explored. In vivo phosphorylation studies in COS-1 cells transfected with murine PPARalpha showed that the level of phosphorylated PPARalpha is increased by treatment with the PP Wy-14,643 as well as the PKC activator phorbol myristol acetate (PMA). In addition, inhibitors of PKC decreased Wy-14,643-induced PPARalpha activity in a variety of reporter assays. Overexpressing PKCalpha, -beta, -delta, and -zeta affected both basal and Wy-14,643-induced PPARalpha activity. Four consensus PKC phosphorylation sites are contained within the DNA binding (C-domain) and hinge (D-domain) regions of rat PPARalpha (S110, T129, S142, and S179), and their contribution to receptor function was examined. Mutation of T129 or S179 to alanine prevented heterodimerization of PPARalpha with RXRalpha, lowered the level of phosphorylation by PKCalpha and PKCdelta in vitro, and lowered the level of phosphorylation of transfected PPARalpha in transfected cells. In addition, the T129A mutation prevented PPARalpha from binding DNA in an electromobility shift assay. Together, these studies demonstrate a direct role for PKC in the regulation of PPARalpha, and suggest several PKCs can regulate PPARalpha activity through multiple phosphorylation sites.

Comprehensive analysis of gene expression in rat and human hepatoma cells exposed to the peroxisome proliferator WY14,643

Peroxisome proliferators (PPs) are an important class of chemicals that act as hepatic tumor promoters in laboratory rodents. The key target for PPs is the nuclear receptor peroxisome proliferator-activated receptor-alpha (PPARalpha) and these chemicals cause cancer by altering the expression of a subset of genes involved in cell growth regulation. The purpose of the present study was to utilize high-density gene expression arrays to examine the genes regulated by the potent PP Wy14,643 (50 microM, 6 h) in both rat (FaO) and human (HepG2) hepatoma cells. Treatment of FaO cells, but not HepG2, revealed the expected fatty acid catabolism genes. However, a larger than expected number of protein kinases, phosphatases, and signaling molecules were also affected exclusively in the FaO cells, including MAPK-phosphatase 1 (MKP-1), Janus-activated kinases 1 and 2 (JAK1 and 2), and glycogen synthetase kinase alpha and beta (GSKalpha and beta). The mRNA accumulation of these genes as well as the protein level for GSK3alpha, JAK1, and JAK2 and MKP-1 activity was corroborated. Due to the importance of MKP-1 in cell signaling, this induction was examined further and was found to be controlled, at least in part, at the level of the gene's promoter. Interestingly, overexpression of MKP-1 in turn affected the constitutive activity of PPARalpha. Taken together, the gene expression arrays revealed an important subset of PP-regulated genes to be kinases and phosphatases. These enzymes not only would affect growth factor signaling and cell cycle control but also could represent feedback control mechanisms and modulate the activity of PPARalpha.

Coxa vara: another option for fixation

Coxa vara is a progressive childhood deformity that is best remedied by a valgus intertrochanteric osteotomy. By restoring the femoral neck and its physis to a more anatomic position, hip mechanics are normalized, with consequent beneficial effects upon hip motion, limb lengths and acetabular development. In the pediatric age group, there is no implant specifically designed for this purpose. Therefore, in addition to the challenge of obtaining adequate correction, inadequate fixation may contribute to recurrent varus deformity, a problem that, according to the literature, has a 30% to 70% prevalence. We are presenting a new technique using a modified veterinary plate for osteosynthesis in children in the 5-year-old to 11-year-old age group. The rationale, implant design, surgical technique and results in a group of nine patients (12 hips) are described.

The early relationship of drug abusing mothers and their infants: an assessment at eight to twelve months of age

Ten mother-infant dyads in which the mother abused drugs during pregnancy were compared to 10 matched drug-free dyads using a short form of the Parent-Child Early Relational Assessment to analyze videotaped mother-infant interactions. Interactions consisted of two five-minute segments: structured and unstructured play. Infants were 8-12 months of age. There was a consistent tendency for the drug abusing group mean scores to separate from the controls. Drug abusing dyads had significantly more (r = .71, Fisher's Exact Probability) ratings below 3.0 in the unstructured play situation for items that measured enthusiasm, responsivity to infant cues, and infant happiness. These categories provide preliminary evidence for those characteristics which may be most problematic in the relationship between drug abusing mothers and their infants, especially in situations in which mother is responsible for providing structure.

Sodium- and chloride-conductive pathways in cultured mouse tracheal epithelium

The utility of a transgenic murine model of cystic fibrosis (CF) lung disease will likely depend on whether the mouse's proximal airway epithelium is characterized by Na(+)- and Cl(-)-conductive pathways comparable to those found in human airways. Therefore, the electrophysiological properties of primary cultures of mouse tracheal epithelium (MTE) were investigated using double-barreled, Cl(-)-selective microelectrodes. Epithelial cells isolated from freshly excised mouse tracheae formed confluent polarized monolayers on permeable collagen supports and developed significant transepithelial potential differences (approximately -10 mV) within 5-6 days postseeding. Under basal conditions, the MTE monolayers had an equivalent short-circuit current (Ieq) of -21.1 +/- 2.1 microA/cm2 and a transepithelial resistance of 424 +/- 49 omega.cm2. Intracellular measurements indicated that the apical (Va) and basolateral (Vb) membrane potential differences were -16.9 +/- 1.5 and -25.4 +/- 1.5 mV, respectively; apical membrane fractional resistance was 0.36 +/- 0.03; and intracellular Cl- activity was 56.1 +/- 2.3 mM. The presence of an apical Na+ conductance was demonstrated by luminal amiloride application (10(-4)M), which decreased Ieq, hyperpolarized Va, and increased the fractional resistance of the apical membrane. The presence of an apical Cl- conductance was demonstrated by substitution of Cl- with gluconate in the luminal bath, which decreased intracellular Cl- activity and increased the fractional resistance of the apical membrane. Luminal application of ATP (10(-4) M was also found to increase the rate of Cl- secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Temporal patterns of cocaine use in pregnancy. Perinatal outcome

Seventy-five cocaine-using women enrolled in a comprehensive perinatal care program were divided into two groups: those who used cocaine in only the first trimester of pregnancy (group 1 [N = 23]) and those who used cocaine throughout pregnancy (group 2 [N = 52]). Perinatal outcomes of these pregnancies were compared with perinatal outcomes of a matched group of obstetric patients with no history or evidence of substance abuse (group 3 [N = 40]). Group 2 women had an increased rate of preterm delivery and low-birth-weight infants as well as an increased rate of intrauterine growth retardation. Group 1 women had rates of these complications similar to the drug-free group. Mean birth weight, length, and head circumference for term infants were reduced in only the group 2 infants. However, both groups of cocaine-exposed infants demonstrated significant impairment of orientation, motor, and state regulation behaviors on the Neonatal Behavioral Assessment Scale.

Ultrasonic imaging of normal fetal response to external vibratory acoustic stimulation

Fetal facial reactions and response decrement patterns to external noise stimulation were studied to characterize normal fetal neurobehavior in the third trimester. Response decrement, or habituation, is thought to reflect higher central nervous system function. Two hundred women with uncomplicated pregnancies, who were subsequently delivered of healthy infants at term, were studied between 26 and 41 weeks' gestation. After ultrasound views of the fetal face were obtained, a vibratory acoustic stimulus was applied repetitively to the maternal abdomen near the fetal head. Response decrement was defined as cessation of all components of the facial reaction, except eye blinking, over two sequential stimuli. Three response patterns were scored: (1) no startle, (2) startle without response decrement, and (3) response decrement by 12 stimuli. Whereas only 53% of fetuses between 26 and 27 weeks displayed startle reaction, all fetuses displayed startle responses by 28 weeks. As gestational age advances, an increasing number of fetuses exhibit response decrement, from no decrement at 26 to 27 weeks to 100% decrement at 40 to 41 weeks. A maturation of neurobehavioral response patterns takes place in normal third-trimester pregnancies. Response decrement testing may be a useful tool for in utero neurologic evaluation.