cPMP rescue of a neonate with severe molybdenum cofactor deficiency after serendipitous early diagnosis, and characterisation of a novel MOCS1 variant.

We report the first, and so far, only index patient with neonatal onset MoCD type A who was diagnosed and treated early enough with cPMP to avoid severe brain injury and disability. The child presented with hypoglycemia at the age of 10 h and was diagnosed because of the incidental finding of severely decreased L-cystine in plasma. Due to a high level of awareness and excellent co-operation between metabolic laboratory and clinical services, cPMP substitution could be initiated before severe encephalopathy set in, and the child subsequently had a normal motor development. The child has been continued on daily substitution with cPMP until today (age 7 years) and has shown a satisfying long-term developmental outcome. Long-term follow-up, however, revealed significant communication difficulties and cognitive abilities in the range of mild to moderate learning disability. The severity of the metabolic disease was confirmed by the extent of biochemical abnormalities and further functional characterisation of the underlying genetic variants. This case provides further evidence that cPMP substitution does significantly alter the disease course when applied early enough. Postnatal treatment in this case was not sufficient to enable an entirely normal cognitive development, despite sustained complete normalization of the biochemical abnormalities.

Reliability of different estimated glomerular filtration rate as measures of renal function in children with sickle cell disease.

BACKGROUND: There is no reliable marker for detecting early renal disease in early children with sickle cell disease (SCD). Estimation of glomerular filtration rate (eGFR) as derived from the height/plasma creatinine formula is dependent on the accuracy of the creatinine analytical method used. The aim of this study was to evaluate different equations for eGFR. METHODS: Children aged 5-16 years recruited. mGFR was obtained using plasma disappearance of Inutest/Iohexol, serum creatinine (SCr) was measured either by standard laboratory method or by tandem mass spectrometry (MSMS). Estimated GFR was then calculated either by "Bedside Schwartz method" or by the full-age spectrum (FAS) equation. FINDINGS: A total of 79 patients (mean age 9.8 ± 4.0 years). A revised eGFR constant was calculated for Schwartz equation from the slope of the plot of height/plasma creatinine versus mGFR. Mean values for mGFR (132.7 ± 32.1 ml/min/1.73m2) and eGFR methods compared: eGFR from standard SCr was significantly higher (144.2 ± 37.3 ml/min/1.73m2, p = 0.008). The MSMS eGFR showed the lowest SD (SD = 27.5), while both FAS eGFR and FAS-height eGFR showed the highest correlation coefficient (r = 0.67). INTERPRETATION: eGFR calculation based on height and SCr determined with MSMS traceable creatinine is more reliable than Schwartz formula using jaffe/enzymatic methods in SCD children.

Validation of a rapid, comprehensive and clinically relevant amino acid profile by underivatised liquid chromatography tandem mass spectrometry.

Background Quantification of plasma amino acids is key to the diagnosis of inherited defects of amino acid synthesis, catabolism and transport, many of which present as clinical emergencies. The utility of this test is limited by the long analysis time and subsequent inability of laboratories to provide results in real-time. Traditionally, analysis has been performed by ion exchange chromatography (IEC) but recently there has been a move towards liquid chromatography tandem mass spectrometry (LC-MS/MS) which provides the potential for faster analysis. However, the necessity to derivatise the sample and/or utilise an ion-pair reagent, combined with lack of commercially available stable isotope internal standards (IS) has prevented laboratories fully exploiting the benefits of this methodology. We describe an underivatised LC-MS/MS method enabling patient results to be reported with an improved turnaround time (<1 h). Methods Methanolic IS was added to plasma (10 µL) to precipitate protein. Following centrifugation amino acids were analysed by LC-MS/MS using selected reaction monitoring (SRM) for each analyte and corresponding IS. Results Patient samples (n = 57) and external quality assessment (EQA) material (n = 11) were analysed and results compared with IEC. Comparable accuracy and precision were obtained with 15-min analysis time. Conclusions This method enables the analysis of a clinically comprehensive amino acid profile without the need for derivatisation/ion-pair reagents and benefitting from improved analytical quantitation through multipoint calibration and use of stable isotope IS. The analysis time is fast in comparison to IEC, improves efficiency of laboratory workflow and enables stat analysis of clinically urgent samples.

Comparative Transcriptomic Response of Primary and Immortalized Macrophages to Murine Norovirus Infection.

Murine norovirus (NoV) is genetically similar to human NoV and offers both an efficient in vitro cell culture system and an animal model by which to investigate the molecular basis of replication. In this study, we present a detailed global view of host alterations to cellular pathways that occur during the progression of a NoV infection. This was accomplished for both Mus musculus BALB/c-derived RAW264.7 (RAW) cells, an immortalized cell line widely used in in vitro replication studies, and primary bone marrow-derived macrophages (BMDM), representing a permissive in vivo target cell in the host. Murine NoV replicated in both cell types, although detected genome copies were approximately one log lower in BMDM compared with RAW cells. RAW and BMDM cells shared an IRF3/7-based IFN response that occurred early in infection. In RAW cells, transcriptional upregulation and INF-ß expression were not coupled in that a significant delay in the detection of secreted INF-ß was observed. In contrast, primary BMDM showed an early upregulation of transcripts and immediate release of INF-ß that might account for lower virus yield. Differences in the transcriptional pathway responses included a marked decrease in expression of key genes in the cell cycle and lipid pathways in RAW cells compared with that of BMDM. Our comparative analysis indicates the existence of varying host responses to virus infection in populations of permissive cells. Awareness of these differences at the gene level will be important in the application of a given permissive culture system to the study of NoV immunity, pathogenesis, and drug development.

Serum kidney injury molecule 1 and ß2-microglobulin perform as well as larger biomarker panels for prediction of rapid decline in renal function in type 2 diabetes.

AIMS/HYPOTHESIS: As part of the Surrogate Markers for Micro- and Macrovascular Hard Endpoints for Innovative Diabetes Tools (SUMMIT) programme we previously reported that large panels of biomarkers derived from three analytical platforms maximised prediction of progression of renal decline in type 2 diabetes. Here, we hypothesised that smaller (n ≤ 5), platform-specific combinations of biomarkers selected from these larger panels might achieve similar prediction performance when tested in three additional type 2 diabetes cohorts. METHODS: We used 657 serum samples, held under differing storage conditions, from the Scania Diabetes Registry (SDR) and Genetics of Diabetes Audit and Research Tayside (GoDARTS), and a further 183 nested case-control sample set from the Collaborative Atorvastatin in Diabetes Study (CARDS). We analysed 42 biomarkers measured on the SDR and GoDARTS samples by a variety of methods including standard ELISA, multiplexed ELISA (Luminex) and mass spectrometry. The subset of 21 Luminex biomarkers was also measured on the CARDS samples. We used the event definition of loss of >20% of baseline eGFR during follow-up from a baseline eGFR of 30-75 ml min-1 [1.73 m]-2. A total of 403 individuals experienced an event during a median follow-up of 7 years. We used discrete-time logistic regression models with tenfold cross-validation to assess association of biomarker panels with loss of kidney function. RESULTS: Twelve biomarkers showed significant association with eGFR decline adjusted for covariates in one or more of the sample sets when evaluated singly. Kidney injury molecule 1 (KIM-1) and ß2-microglobulin (B2M) showed the most consistent effects, with standardised odds ratios for progression of at least 1.4 (p < 0.0003) in all cohorts. A combination of B2M and KIM-1 added to clinical covariates, including baseline eGFR and albuminuria, modestly improved prediction, increasing the area under the curve in the SDR, Go-DARTS and CARDS by 0.079, 0.073 and 0.239, respectively. Neither the inclusion of additional Luminex biomarkers on top of B2M and KIM-1 nor a sparse mass spectrometry panel, nor the larger multiplatform panels previously identified, consistently improved prediction further across all validation sets. CONCLUSIONS/INTERPRETATION: Serum KIM-1 and B2M independently improve prediction of renal decline from an eGFR of 30-75 ml min-1 [1.73 m]-2 in type 2 diabetes beyond clinical factors and prior eGFR and are robust to varying sample storage conditions. Larger panels of biomarkers did not improve prediction beyond these two biomarkers.

Evaluating Supervision Models in Functional Family Therapy: Does Adding Observation Enhance Outcomes?

This study examined the effects of observation-based supervision Building Outcomes with Observation-Based Supervision of Therapy (BOOST therapists = 26, families = 105), versus supervision as usual (SAU therapists = 21, families = 59) on (a) youth externalizing behavior problems and (b) the moderating effects of changes in family functioning on youth externalizing behaviors for adolescents receiving Functional Family Therapy (FFT). Exploratory analyses examined the impact of supervision conditions on youth internalizing problems. In 8 community agencies, experienced FFT therapists (M = 1.4 years) received either BOOST or SAU supervision in a quasi-experimental design. Male (59%) or female (41%) adolescents were referred for the treatment of behavior problems (e.g., delinquency, substance use). Clients were Hispanic (62%), African American (19%), Non-Hispanic White (12%), or Other (7%) ethnic/racial origins. Therapists (female, 77%) were Hispanic 45%, African American (19%), White Non-Hispanic (30%), or other (4%) ethnic/racial backgrounds. Analyses controlled for the presence or absence of clinically elevated symptoms on outcome variables. Clinical outcomes were measured at baseline, 5 months, and 12 months after treatment initiation. Clients with externalizing behavior above clinical thresholds had significantly greater reductions in problem behaviors in the BOOST versus the SAU conditions. Clients below thresholds did not respond differentially to conditions. Supervisors in BOOST had more experience with the FFT model; as such, the observed results may be a result of supervisor experience. The BOOST supervision was associated with improved outcomes on problem behaviors that were above clinical thresholds. The findings demonstrate the importance of addressing client case mix in implementation studies in natural environments.

Este estudio examinó los efectos de la supervisión basada en la observación (terapeutas de BOOST = 26, familias = 105) frente a la supervisión habitual (terapeutas de SAU = 21, familias = 59) en (a) la externalización de problemas de conducta en los jóvenes y (b) los efectos moderadores de los cambios en el funcionamiento familiar sobre la externalización de conductas de los jóvenes en el caso de adolescentes que reciben terapia familiar funcional (FFT). Los análisis exploratorios analizaron el efecto de las condiciones de la supervisión en la internalización de problemas de los jóvenes. En 8 agencias comunitarias, terapeutas experimentados en FFT (M = 1,4 años) recibieron supervisión BOOST o SAU en un diseño cuasiexperimental. Se derivó a adolescentes masculinos (59%) o femeninos (41%) para el tratamiento de problemas conductuales (p. ej.: delincuencia, consumo de sustancias). Los pacientes eran hispanos (62%), afroamericanos (19%), blancos no hispanos (12%) o de otros orígenes étnicos o raciales (7%). Los terapeutas (femeninos, 77%) eran hispanos 45%, afroamericanos (19%), blancos no hispanos (30%) o de otros orígenes étnicos o raciales (4%). Los análisis tuvieron en cuenta la presencia o la ausencia de síntomas clínicamente elevados en los criterios de valoración. Se midieron las variables clínicas al inicio, a los 5 meses y 12 meses después del inicio del tratamiento. Resultados: Los pacientes con externalización del comportamiento por encima de los límites clínicos tuvieron reducciones considerablemente mayores de los comportamientos problemáticos en las condiciones de BOOST frente a las de SAU. Los pacientes por debajo de los límites no respondieron de forma diferencial a las condiciones. Los supervisores de BOOST tenían más experiencia con el modelo de FFT; por lo tanto, los resultados observados pueden ser el resultado de la experiencia de los supervisores. La supervisión BOOST estuvo asociada con mejores resultados en los comportamientos problemáticos que estaban por encima de los límites clínicos. Los resultados demuestran la importancia de abordar la variedad de casos de pacientes en la implementación de estudios en ambientes naturales.

Juvenile Justice Risk Factors and Functional Family Therapy Fidelity on Felony Recidivism.

Families (n = 5,884) received Functional Family Therapy (FFT) provided as part of court-ordered probation services by 11 community sites throughout Florida. Sites provided home-based FFT to families with male (72%) or female (28%) delinquent youth. Juvenile justice courts referred clients to these services in an effort to redirect them away from incarceration. Clients were Hispanic (18%), Black (41%), and White Non-Hispanic (36%), while therapists (female, 79%) were of Hispanic (28%), Black (20%), and White Non-Hispanic (50%) ethnic/racial origins. Analyses of clients' pretreatment recidivism risk and therapist's caseload of risky clients demonstrated that both individual and treatment site case-mix of client criminal risk levels were associated with higher adjudicated felony recidivism. Furthermore, clinical process indicators suggest that therapists with larger rather than smaller caseloads of high-risk clients provided treatment with greater fidelity. Results suggest that experience in working with challenging clients is critical for achieving fidelity with these cases.

Newborn screening for sickle cell disease in Europe: recommendations from a Pan-European Consensus Conference.

Sickle Cell Disease (SCD) is an increasing global health problem and presents significant challenges to European health care systems. Newborn screening (NBS) for SCD enables early initiation of preventive measures and has contributed to a reduction in childhood mortality from SCD. Policies and methodologies for NBS vary in different countries, and this might have consequences for the quality of care and clinical outcomes for SCD across Europe. A two-day Pan-European consensus conference was held in Berlin in April 2017 in order to appraise the current status of NBS for SCD and to develop consensus-based statements on indications and methodology for NBS for SCD in Europe. More than 50 SCD experts from 13 European countries participated in the conference. This paper aims to summarise the discussions and present consensus recommendations which can be used to support the development of NBS programmes in European countries where they do not yet exist, and to review existing programmes.

Continuous Infusion of Low-Dose Iohexol Measures Changing Glomerular Filtration Rate in Critically Ill Patients.

OBJECTIVE: Measurement of changing glomerular filtration rate in acute kidney injury remains problematic. We have previously used a continuous infusion of low-dose Iohexol to measure glomerular filtration rate in stable subjects and postulate that changes greater than 10.3% in critically ill patients indicate acute kidney injury. Our objective is to explore the extent to which continuous infusion of low-dose Iohexol can be a measure of changing glomerular filtration rate during acute kidney injury. DESIGN: Clinical observational exploratory study. SETTING: Adult ICU. PATIENTS: Three patient groups were recruited: nephrectomy group: predictable onset of acute kidney injury and outcome (n = 10); surgery group: predictable onset of acute kidney injury, unpredictable outcome (n = 11); and acute kidney injury group: unpredictable onset of acute kidney injury and outcome (n = 13). INTERVENTIONS: Continuous infusion of low-dose Iohexol was administered for 24-80 hours. Plasma (ClP) and renal (ClR) Iohexol clearances were measured at timed intervals. MEASUREMENTS AND MAIN RESULTS: Kidney Disease: Improved Global Outcomes acute kidney injury criteria were fulfilled in 22 patients (nephrectomy = 5, surgery = 4, and acute kidney injury = 13); continuous infusion of low-dose Iohexol demonstrated acute kidney injury in 29 patients (nephrectomy = 10, surgery = 8, acute kidney injury = 11). Dynamic changes in glomerular filtration rate were tracked in all patients. In the nephrectomy group, ClR decreased by an expected 50% (50.8% ± 11.0%). Agreement between ClP and ClR improved with increasing duration of infusion: bias of ClP versus ClR at 48 hours was -0.1 ± 3.6 mL/min/1.73 m (limits of agreement: -7.2 to 7.1 mL/min/1.73 m). Coefficient of variation of laboratory sample analysis was 2.4%. CONCLUSIONS: Continuous infusion of low-dose Iohexol is accurate and precise when measuring glomerular filtration rate and tracks changes in patients with differing risks of acute kidney injury. Continuous infusion of low-dose Iohexol may provide a useful standard against which to test novel biomarkers for the diagnosis of acute kidney injury.

Depression Change Profiles in Adolescents Treated for Comorbid Depression/Substance Abuse and Profile Membership Predictors.

Using data from a randomized trial in which adolescents with depressive and substance use disorders (SUD) received treatments for both disorders in either a sequenced or coordinated manner, we (a) determine the number and nature of depression response profiles through 1-year posttreatment and (b) examine whether 8 previously identified factors predict profile membership. There were 170 adolescents (M age = 16.4 years; 22% female; 28% Hispanic, 61% Non-Hispanic White) with comorbid depressive disorder/SUD randomized to one of three sequences of receiving the Adolescent Coping With Depression Course and Functional Family Therapy for SUD (depression treatment followed by SUD treatment; SUD treatment followed by depression treatment; coordinated treatment). Depression was assessed at 7 points from baseline to 1-year follow-up. A 4-class solution fit the data best, with groups labeled Mildly Depressed Responders (57.1%), Depressed Responders (18.8%), Depressed Non-Responders (12.9%), and Depressed with Recurrence (11.2%). The 4 change profiles differed on indices of all but 1 predictor (age); most differences were driven by lower scores among Mildly Depressed Responders. Profile membership was most strongly predicted by depression severity, cognitive distortions, hopelessness, and global functioning. The strongest predictor of Nonresponse was low family cohesion, whereas Recurrence was associated with hopelessness, suicide attempts, and starting treatment near the end of the school year. Most depressed adolescents experienced a positive response that was maintained. Understanding the most common profiles of depression change during and following treatment and the variables that predict change can help improve treatment outcomes and advance tailoring efforts.

A Conceptual Model and Clinical Framework for Integrating Mindfulness into Family Therapy with Adolescents.

Individual and group-based psychotherapeutic interventions increasingly incorporate mindfulness-based principles and practices. These practices include a versatile set of skills such as labeling and attending to present-moment experiences, acting with awareness, and avoiding automatic reactivity. A primary motivation for integrating mindfulness into these therapies is compelling evidence that it enhances emotion regulation. Research also demonstrates that family relationships have a profound influence on emotion regulation capacities, which are central to family functioning and prosocial behavior more broadly. Despite this evidence, no framework exists to describe how mindfulness might integrate into family therapy. This paper describes the benefits of mindfulness-based interventions, highlighting how and why informal mindfulness practices might enhance emotion regulation when integrated with family therapy. We provide a clinical framework for integrating mindfulness into family therapy, particularly as it applies to families with adolescents. A brief case example details sample methods showing how incorporating mindfulness practices into family therapy may enhance treatment outcomes. A range of assessment modalities from biological to behavioral demonstrates the breadth with which the benefits of a family-based mindfulness intervention might be evaluated.

Kynurenine Pathway Activation in Human African Trypanosomiasis.

Background: The kynurenine pathway of tryptophan oxidation is associated with central nervous system (CNS) inflammatory pathways. Inhibition of this pathway ameliorates CNS inflammation in rodent models of the late (meningoencephalitic) stage of human African trypanosomiasis (HAT). In this study, we evaluate whether the kynurenine pathway is activated in clinical HAT and associated with CNS inflammatory responses. Methods: We measured cerebrospinal fluid (CSF) tryptophan and kynurenine metabolite concentrations in patients infected with Trypanosoma brucei rhodesiense, using liquid chromatography-mass spectrometry. Results: Kynurenine concentration in CSF was increased in both the early and late stages of disease, with a progressive increase in tryptophan oxidation associated with stage progression. Kynurenine pathway activation was associated with increases in neuroinflammatory markers, but there was no clear relationship to neurological symptoms. Conclusions: CNS kynurenine pathway activation occurs during HAT, including cases prior to the current diagnostic cutoff for late-stage infection, providing evidence for early CNS involvement in HAT. Metabolite data demonstrate that the kynurenine-3-monooxygenase and kynurenine aminotransferase branches of the kynurenine pathway are active. The association between tryptophan oxidation and CNS inflammatory responses as measured by CSF interleukin 6 (IL-6) concentration supports a role of kynurenine metabolites in the inflammatory pathogenesis of late-stage HAT.

Evolution of Functional Family Therapy as an Evidence-Based Practice for Adolescents with Disruptive Behavior Problems.

This article summarizes the evolution of functional family therapy (FFT) based upon four decades of clinical practice and scientific scrutiny through research evidence. FFT research has evolved from an initial focus upon clinical process research, which examined sequential exchanges between therapists and family members. A key element of this research has been an examination of the way in which clinicians acquire, consolidate, and maintain the skills needed to implement FFT effectively with youth and families. Many randomized efficacy and effectiveness studies have evaluated the impact of FFT across diverse clinical populations. Subsequent research investigated factors that influence the effectiveness of implementation across more than 300 clinical settings in which more than 2,500 trained clinicians have provided service to nearly 400,000 families. Another important set of investigations concerned the cost-effectiveness of the interventions.

Biomarkers of rapid chronic kidney disease progression in type 2 diabetes.

Here we evaluated the performance of a large set of serum biomarkers for the prediction of rapid progression of chronic kidney disease (CKD) in patients with type 2 diabetes. We used a case-control design nested within a prospective cohort of patients with baseline eGFR 30-60 ml/min per 1.73 m(2). Within a 3.5-year period of Go-DARTS study patients, 154 had over a 40% eGFR decline and 153 controls maintained over 95% of baseline eGFR. A total of 207 serum biomarkers were measured and logistic regression was used with forward selection to choose a subset that were maximized on top of clinical variables including age, gender, hemoglobin A1c, eGFR, and albuminuria. Nested cross-validation determined the best number of biomarkers to retain and evaluate for predictive performance. Ultimately, 30 biomarkers showed significant associations with rapid progression and adjusted for clinical characteristics. A panel of 14 biomarkers increased the area under the ROC curve from 0.706 (clinical data alone) to 0.868. Biomarkers selected included fibroblast growth factor-21, the symmetric to asymmetric dimethylarginine ratio, ß2-microglobulin, C16-acylcarnitine, and kidney injury molecule-1. Use of more extensive clinical data including prebaseline eGFR slope improved prediction but to a lesser extent than biomarkers (area under the ROC curve of 0.793). Thus we identified several novel associations of biomarkers with CKD progression and the utility of a small panel of biomarkers to improve prediction.

Validation of a continuous infusion of low dose Iohexol to measure glomerular filtration rate: randomised clinical trial.

INTRODUCTION: There is currently no accurate method of measuring glomerular filtration rate (GFR) during acute kidney injury (AKI). Knowledge of how much GFR varies in stable subjects is necessary before changes in GFR can be attributed to AKI. We have designed a method of continuous measurement of GFR intended as a research tool to time effects of AKI. The aims of this crossover trial were to establish accuracy and precision of a continuous infusion of low dose Iohexol (CILDI) and variation in GFR in stable volunteers over a range of estimated GFR (23-138 mL/min/1.73 m(2)). METHODS: We randomised 17 volunteers to GFR measurement by plasma clearance (PC) and renal clearance (RC) of either a single bolus of Iohexol (SBI; routine method), or of a continuous infusion of low dose Iohexol (CILDI; experimental method) at 0.5 mL/h for 12 h. GFR was measured by the alternative method after a washout period (4-28 days). Iohexol concentration was measured by high performance liquid chromatography/electrospray tandem mass spectrometry and time to steady state concentration (Css) determined. RESULTS: Mean PC was 76.7 ± 28.5 mL/min/1.73 m(2) (SBI), and 78.9 ± 28.6 mL/min/1.73 m(2) (CILDI), p = 0.82. No crossover effects occurred (p = 0.85). Correlation (r) between the methods was 0.98 (p < 0.0001). Bias was 2.2 mL/min/1.73 m(2) (limits of agreement -8.2 to 12.6 mL/min/1.73 m(2)) for CILDI. PC overestimated RC by 7.1 ± 7.3 mL/min/1.73 m(2). Mean intra-individual variation in GFR (CILDI) was 10.3% (p < 0.003). Mean ± SD Css was 172 ± 185 min. CONCLUSION: We hypothesise that changes in GFR >10.3% depict evolving AKI. If this were applicable to AKI, this is less than the 50% change in serum creatinine currently required to define AKI. CILDI is now ready for testing in patients with AKI. TRIAL REGISTRATION: This trial was registered with the European Union Clinical Trials Register ( https://www.clinicaltrialsregister.eu/ ), registration number: 2010-019933-89 .

Relationship of FGF23 to indexed left ventricular mass in children with non-dialysis stages of chronic kidney disease.

BACKGROUND: The aim of this study was to evaluate the association of serum intact fibroblast growth factor 23 (FGF23) concentrations with indexed left ventricular mass in children with non-dialysis stages 3-5 of chronic kidney disease (CKD). METHODS: The study cohort comprised 83 children (51 boys; mean age 12.1 ± 3.2 years) with a mean estimated glomerular filtration rate (eGFR) of 32.3 ± 14.6 ml/min/1.73 m(2) who underwent clinic and ambulatory blood pressure measurement (ABPM), echocardiography and evaluation of biochemical markers of CKD-associated mineral bone disease. RESULTS: The mean left ventricular mass index (LVMI) was 35.9 ± 8.5 g/m(2.7) (± standard deviation), with 30 (36.1 %) children showing left ventricular hypertrophy (LVH), all eccentric, as defined using age-specific criteria. For all subjects, the mean FGF23 concentration was 142.2 ± 204.4 ng/l and the normalised distribution following log transformation was 1.94 ± 0.39. There was significant univariate correlation of LVMI with GFR, body mass index (BMI) z-score and calcium intake, but not with 24-h systolic ABPM z-score, log intact parathyroid hormone or log FGF23. On multivariate analysis following adjustment for confounders, only elemental calcium content (g/kg/day) estimated from prescribed calcium-based phosphate binder dose (ß = 154.9, p < 0.001) and BMI z-score (ß = 2.397, p = 0.003) maintained a significant positive relationship with LVMI (model r (2) = 0.225). CONCLUSIONS: We observed no significant relationship of FGF23 with LVMI. Larger studies in children are needed to clarify the roles of calcium-containing phosphate binders and FGF23 with LV mass and their roles in the evolution of the development of adverse cardiovascular outcomes.

Estrogen receptor-ß regulates mechanical signaling in primary osteoblasts.

Mechanical loading is an important regulator in skeletal growth, maintenance, and aging. Estrogen receptors have a regulatory role in mechanically induced bone adaptation. Estrogen receptor-α (ERα) is known to enhance load-induced bone formation, whereas ERß negatively regulates this process. We hypothesized that ERß regulates mechanical signaling in osteoblasts. We tested this hypothesis by subjecting primary calvarial cells isolated from wild-type and ERß-knockout mice (BERKO) to oscillatory fluid flow in the absence or presence of estradiol (E2). We found that the known responses to fluid shear stress, i.e., phosphorylation of the mitogen-activated protein kinase ERK and upregulation of COX-2 expression, were inhibited in BERKO cells in the absence of E2. Flow-induced increase in prostaglandin E2 (PGE2) release was not altered in BERKO cells in the absence of E2, but was increased when E2 was present. Additionally, immunofluorescence analysis and estrogen response element luciferase assays revealed increased ERα expression and flow- and ligand-induced nuclear translocation as well as transcriptional activity in BERKO cells in both the presence and absence of E2. Taken together, these data suggest that ERß plays both ligand-dependent and ligand-independent roles in mechanical signaling in osteoblasts. Furthermore, our data suggest that one mechanism by which ERß regulates mechanotransduction in osteoblasts may result from its inhibitory effect on ERα expression and function. Targeting estrogen receptors (e.g., inhibiting ERß) may represent an effective approach for prevention and treatment of age-related bone loss.