Evaluating hormonal mechanisms of vitamin D receptor agonist therapy in diabetic kidney disease: the VALIDATE-D study

Background: Insufficient vitamin D status and increased renin-angiotensin system (RAS) activity have been associated with renal-vascular disease and nephropathy in diabetes. Accumulating evidence indicates that vitamin D receptor (VDR) activation lowers unfavorable RAS activity; however, more human intervention studies evaluating whether this mechanism could influence diabetic kidney disease are needed. We previously reported that both vitamin D levels and genetic variation at the VDR predict human RAS activity, and that vitamin D therapy can lower RAS activity in non-diabetics. The VALIDATE-D study is a randomized, placebo-controlled, intervention study designed to extend these findings by evaluating whether direct VDR activation in diabetes lowers circulating and local renal-vascular tissue RAS activity (Aims 1 and 2) in a manner similar to the action of ACE inhibitors (Aim 3). Methods/Design Forty subjects with type 2 diabetes, microalbuminuria, and without chronic kidney disease will be recruited to undergo detailed assessment of the RAS before and after randomization to calcitriol 0.75 mcg/day or placebo. Primary analyses will evaluate whether calcitriol therapy reduces circulating and renal-vascular tissue-RAS activity in comparison to placebo. All subjects will thereafter be treated with lisinopril and followed for 3.5 months to evaluate whether combination therapy (calcitriol + lisinopril vs. placebo + lisinopril) additively or synergistically improves renal-vascular function, and lowers proteinuria. Discussion The VALIDATE-D study is the first human intervention study to evaluate whether direct VDR activation can lower the human RAS in diabetes, compared to the effect of an ACE inhibitor, and whether this mechanism can translate to clinically relevant endpoints for diabetic kidney disease. The outcomes of VALIDATE-D will have major implications for the recommendation of vitamin D supplementation for the primary prevention of kidney complications in diabetes. Trial registration ClinicalTrials.gov, NCT0163506

Ischemic Stroke in Children and Young Adults with Sickle Cell Disease (SCD) in the Post-STOP Era

Abstract Background: The Stroke Prevention Trial in Sickle Cell Anemia (STOP) and Optimizing Primary Stroke Prevention in Sickle Cell Anemia (STOP 2) established routine transcranial Doppler ultrasound (TCD) screening with indefinite chronic red cell transfusions (CRCT) for children with abnormal TCD as standard of care. To identify children at high-risk of stroke, annual TCD screening is recommended from ages 2 to 16 years, with more frequent monitoring if the result is not normal. A reduction in stroke incidence in children with SCD has been reported in several clinical series and analyses utilizing large hospital databases when comparing rates before and after the publication of the STOP study in 1998. We sought to determine the rate of first ischemic stroke in a multicenter cohort of children who had previously participated in the STOP and/or STOP 2 trials and to determine whether these strokes were screening or treatment failures. Subjects and Methods: Between 1995 and 2005, STOP and STOP 2 (STOP/2) were conducted at 26 sites in the US and Canada. These studies included 3,835 children, ages 2 to 16 y with SCD type SS or S-beta-0-thalassemia. Participation in STOP/2 ranged from a single screening TCD to randomization. STOP 2 also had an observational arm for children on CRCT for abnormal TCD whose TCD had not reverted to normal. The Post-STOP study was designed to follow-up the outcomes of children who participated in one or both trials. 19 of the 26 original study sites participated in Post-STOP, contributing a total of 3,539 (92%) of the STOP/2 subjects. After exit from STOP/2, these children received TCD screening and treatment according to local practices. Data abstractors visited each clinical site and obtained retrospective data from STOP/2 study exit to 2012-2014 (depending on site) including follow-up TCD and brain imaging results, clinical information, and laboratory results. Two vascular neurologists, blinded to STOP/2 status and prior TCD and neuroimaging results, reviewed source records to confirm all ischemic strokes, defined as a symptomatic cerebral infarction; discordant opinions were resolved through discussion. For the first Post-STOP ischemic stroke, prior TCD result and treatment history subsequently were analyzed. Results: Of the 3,539 subjects, follow-up data were available for 2,850 (81%). Twelve children who had a stroke during STOP or STOP2 were excluded from these analyses resulting in data on 2,838 subjects. The mean age at the start of Post-STOP was 10.5 y and mean duration of follow-up after exiting STOP/2 was 9.1 y. A total of 69 first ischemic strokes occurred in the Post-STOP observation period (incidence 0.27 per 100 pt years). The mean age at time of stroke was 14.4±6.2 (median 13.8, range 3.5-28.9) y. Twenty-five of the 69 patients (36%) had documented abnormal TCD (STOP/2 or Post-STOP) prior to the stroke; 15 (60%) were receiving CRCT and 9 (36%) were not (treatment data not available for 1 subject). Among the 44 subjects without documented abnormal TCD, 29 (66%) had not had TCD re-screen in the Post-STOP period prior to the event; 7 of these 29 (24%) were 16 y or older at the start of Post-STOP, which is beyond the recommended screening age. Four of the 44 (9%) patients had inadequate TCD in Post-STOP (1 to 10.7 y prior to event). Six (14%) had normal TCD more than a year before the event (1.2 - 4 y); all but one of these children were younger than 16 y at the time of that TCD. Only 5 (11%) had a documented normal TCD less than 1 year prior to the event. Conclusions: In the Post-STOP era, the rate of first ischemic stroke was substantially lower than that reported in the Cooperative Study of Sickle Cell Disease, prior to implementation of TCD screening. Many (39%) of the Post-STOP ischemic strokes were associated with a failure to re-screen according to current guidelines, while only 11% occurred in children who had had recent low-risk TCD. Among those known to be at high risk prior to stroke, treatment refusal or inadequate treatment may have contributed. While TCD screening and treatment are effective at reducing ischemic stroke in clinical practice, significant gaps in screening and treatment, even at sites experienced in the STOP protocol, remain to be addressed. Closing these gaps should provide yet further reduction of ischemic stroke in SCD. Disclosures No relevant conflicts of interest to declare

Transcranial doppler re-screening of subjects who participated in STOP and STOP II.

In children with Sickle Cell Disease, the combination of risk stratification with Transcranial Doppler Ultrasound (TCD) and selective chronic red cell transfusion (CRCT-the STOP Protocol) is one of the most effective stroke prevention strategies in medicine. How fully it is being implemented is unclear. Nineteen of 26 sites that conducted the two pivotal clinical trials (STOP and STOP II) participated in Post STOP, a comprehensive medical records review assessing protocol implementation in the 10-15 years since the trials ended. Professional abstractors identified medical records in the Post STOP era in 2851 (74%) of the 3,840 children who took part in STOP and/or STOP II, and documented TCD rescreening, maintenance of CRCT in those at risk, and stroke. Among 1,896 children eligible for TCD rescreening (target group), evidence of any rescreening was found in 1,090 (57%). There was wide site variation in TCD rescreening ranging from 18% to 91% of eligible children. Both younger age and having a conditional TCD during STOP/II were associated with a higher likelihood of having a TCD in Post STOP. Sixty eight new abnormal, high risk cases were identified. Despite clear evidence of benefit the STOP protocol is not fully implemented even at experienced sites. Site variation suggests that system improvements might remove barriers to implementation and result in even greater reduction of ischemic stroke in children with SCD. Am. J. Hematol. 91:1191-1194, 2016. © 2016 Wiley Periodicals, Inc

Ethnic and socioeconomic variation in incidence of congenital heart defects

Introduction: Ethnic differences in the birth prevalence of congenital heart defects (CHDs) have been reported; however, studies of the contemporary UK population are lacking. We investigated ethnic variations in incidence of serious CHDs requiring cardiac intervention before 1 year of age. Methods: All infants who had a cardiac intervention in England and Wales between 1 January 2005 and 31 December 2010 were identified in the national congenital heart disease surgical audit and matched with paediatric intensive care admission records to create linked individual child records. Agreement in reporting of ethnic group by each audit was evaluated. For infants born 1 January 2006 to 31 December 2009, we calculated incidence rate ratios (IRRs) for CHDs by ethnicity and investigated age at intervention, antenatal diagnosis and area deprivation. Results: We identified 5350 infants (2940 (55.0%) boys). Overall CHD incidence was significantly higher in Asian and Black ethnic groups compared with the White reference population (incidence rate ratios (IRR) (95% CIs): Asian 1.5 (1.4 to 1.7); Black 1.4 (1.3 to 1.6)); incidence of specific CHDs varied by ethnicity. No significant differences in age at intervention or antenatal diagnosis rates were identified but affected children from non-White ethnic groups were more likely to be living in deprived areas than White children. Conclusions: Significant ethnic variations exist in the incidence of CHDs, including for specific defects with high infant mortality. It is essential that healthcare provision mitigates ethnic disparity, including through timely identification of CHDs at screening, supporting parental choice and effective interventions. Future research should explore the factors underlying ethnic variation and impact on longer-term outcomes

Cell cycle analysis of MDA-MB-157 and APC knockdown cells

Background and Hypothesis: A majority of sporadic breast cancers include deficits in the expression of Adenomatous Polyposis Coli (APC), a tumor suppressor. Deficits in APC are more common in patients with TNBC (triple negative breast cancer), which is also a cancer prone to chemotherapy resistance. The Prosperi lab previously found that APC knockdown cells (APCKD) were resistant to Paclitaxel (PTX). We hypothesize that APCKD cells are resistant to PTX treatment through avoidance of G2/M arrest. This summer, my goal was to investigate the mechanism by which PTX works to arrest the cell cycle at G2/M.  Experimental Design or Project Methods: Cell Synchronization: To synchronize MDA-MB-157 and APCKD cells, we first tried serum starvation for 24-72 hours. Second, we tried synchronizing the cells using a double thymidine block as described (Bostock, 1971). In either protocol, cells were then stained with Propidium Iodide (PI) and flow cytometry was performed. Paclitaxel (PTX) treatment and cell cycle analysis: MDA-MB-157 and APCKD cells were grown to confluency and then treated with 0.078µM PTX for 12, 24, and 48 hours. Cells were stained with PI and flow cytometry was performed. Results: Cell synchronization: APCKD cells cells have an increased cell population in the G2/M phase than the parental cells after serum starvation. Importantly, APC knockdown cells are not impacted by serum starvation up to 72 hours. Additionally, a double thymidine block is insufficient to synchronize MDA-MB-157 and APCKD cells. A double thymidine block did shorten the S phase and move MDA-MB-157 and APCKD cells closer to G0-G1 arrest, but did not synchronize. Paclitaxel (PTX) treatment and cell cycle analysis: MDA-MB-157 and APCKD cells treated for longer intervals experienced more cell death and were further arrested in G2/M. Conclusion and Potential Impact: We learned that MDA-MB-157 and APCKD cannot be easily synchronized using serum starving or a double thymidine block. Future investigations will require alternative methods of synchronization or will proceed without synchronization. Furthermore, APCKD cells do not avoid G2/M arrest when treated with Paclitaxel, indicating a different mechanism of PTX resistance

Going home after infant cardiac surgery: a UK qualitative study

National Institute for Health Research Health Services and Delivery Research programme (Project No: 10/2002/29)

Interplay between hydrophilic and hydrophobic interactions in the self-assembly of a gemini amphiphilic pseudopeptide: from nano-spheres to hydrogels

The formation of soluble nano-spheres or stable hydrogels through the self-assembling of a simple gemini amphiphilic pseudopeptide can be controlled by the tuning of the hydrophilic/hydrophobic interactions in aqueous medium

NHS cadet schemes: student experience, commitment, job satisfaction and job stress

In the context of various policy initiatives concerning widening access to and strengthening recruitment and retention in the health services, cadet schemes – predominantly in nursing – have proliferated over the last few years. As part of a larger national evaluation of National Health Service (NHS) cadet schemes, this paper reports on a survey of senior cadet students across 62 cadet schemes in England and examines their experience of being a cadet on such a scheme. Cadets forming the most senior cohort from each of the 62 schemes (n=596) were surveyed using a questionnaire. The questionnaire included self-rated measures of job satisfaction, job stress and commitment. A 5% sample of these cadets participated in follow-up telephone interviews. Cadets reported high satisfaction with their courses. One of the most positive aspects of the schemes was the first-hand experience of working in the NHS they provided, whilst also giving cadets the opportunity to gain recognisable skills and qualifications. Cadets scored highly on the job satisfaction scale and, on the job stress scale, showed low stress overall. A significant positive correlation was found between satisfaction and stress, indicating that the cadets who are most satisfied are also more highly stressed. A negative correlation was found between stress and the dimensions of commitment indicating that those cadets who are stressed are less committed to the NHS. A negative correlation was also found between satisfaction and the dimensions of commitment, suggesting that commitment to the NHS is not contingent on high satisfaction. The implications for the findings of the survey are discussed

Efficacy and Safety of Baxdrostat in Uncontrolled and Resistant Hypertension

BACKGROUND: Aldosterone dysregulation plays an important pathogenic role in hard-to-control hypertension. In several studies, baxdrostat, an aldosterone synthase inhibitor, reduced the seated systolic blood pressure of patients with uncontrolled or resistant hypertension. METHODS: In this phase 3, multinational, double-blind, randomized, placebo-controlled trial, we recruited patients with a seated systolic blood pressure of between 140 mm Hg and less than 170 mm Hg despite the receipt of stable treatment with two antihypertensive medications (uncontrolled hypertension) or three or more such medications (resistant hypertension), including a diuretic. After a 2-week placebo run-in period, we randomly assigned patients with a seated systolic blood pressure of 135 mm Hg or more in a 1:1:1 ratio to receive baxdrostat at a dose of 1 mg, baxdrostat at a dose of 2 mg, or placebo once daily for 12 weeks. The primary end point was the change in seated systolic blood pressure from baseline to week 12. RESULTS: A total of 796 patients underwent randomization and 794 received 1-mg baxdrostat (264 patients), 2-mg baxdrostat (266 patients), or placebo (264 patients) in addition to background therapy. At 12 weeks, the change from baseline in the least-squares mean seated systolic blood pressure was -14.5 mm Hg (95% confidence interval [CI], -16.5 to -12.5) with 1-mg baxdrostat, -15.7 mm Hg (95% CI, -17.6 to -13.7) with 2-mg baxdrostat, and -5.8 mm Hg (95% CI, -7.9 to -3.8) with placebo. The estimated difference from placebo (placebo-corrected difference) was -8.7 mm Hg (95% CI, -11.5 to -5.8) with 1-mg baxdrostat and -9.8 mm Hg (95% CI, -12.6 to -7.0) with 2-mg baxdrostat (P<0.001 for both comparisons). A potassium level of more than 6.0 mmol per liter was reported in 6 patients (2.3%) with 1-mg baxdrostat, in 8 patients (3.0%) with 2-mg baxdrostat, and in 1 patient (0.4%) with placebo. CONCLUSIONS: Among patients with uncontrolled or resistant hypertension, the addition of baxdrostat to background therapy resulted in a significantly lower seated systolic blood pressure at 12 weeks than placebo. (Funded by AstraZeneca and others; BaxHTN ClinicalTrials.gov number, NCT06034743.)