Citations

Context: Prediabetes is a heterogeneous disorder classified on the basis of fasting glucose concentrations and 2-hour glucose tolerance. Objective: We sought to determine the relative contributions of insulin secretion and action to the pathogenesis of isolated impaired glucose tolerance (IGT). Design: The study consisted of an oral glucose tolerance test and a euglycemic clamp performed in two cohorts matched for anthropometric characteristics and fasting glucose but discordant for glucose tolerance. Setting: An inpatient clinical research unit at an academic medical center. Patients or Other Participants: Twenty-five subjects who had normal fasting glucose (NFG) and normal glucose tolerance (NGT) and 19 NFG/IGT subjects participated in this study. Intervention(s): Subjects underwent a seven-sample oral glucose tolerance test and a 4-hour euglycemic, hyperinsulinemic clamp on separate occasions. Glucose turnover during the clamp was measured using tracers, and endogenous hormone secretion was inhibited by somatostatin. Main Outcome Measures: We sought to determine whether hepatic glucose metabolism, specifically the contribution of gluconeogenesis to endogenous glucose production, differed between subjects with NFG/NGT and those with NFG/IGT. Results: Endogenous glucose production did not differ between groups before or during the clamp. Insulin-stimulated glucose disappearance was lower in NFG/IGT (24.6 ± 2.2 vs 35.0 ± 3.6 μmol/kg/min; P = .03). The disposition index was decreased in NFG/IGT (681 ± 102 vs 2231 ± 413 × 10−14 dL/kg/min2 per pmol/L; P < .001). Conclusions: We conclude that innate defects in the regulation of glycogenolysis and gluconeogenesis do not contribute to NFG/IGT. However, insulin-stimulated glucose disposal is impaired, exacerbating defects in β-cell function.

BACKGROUNDHydroxyethyl starch (HES) is reportedly associated with an increased risk of renal failure and death when used for fluid resuscitation in critically ill patients. HES can be used during therapeutic leukocytapheresis (TL) procedures to enhance cell separation. The purpose of this study was to evaluate the occurrence of adverse events associated with HES during TL procedures.STUDY DESIGN AND METHODSWe performed a retrospective review of patients who underwent TL with and without HES in the period 2009 to 2013 at six academic medical institutions.RESULTSA difference‐in‐difference regression analysis was used to estimate the mean change before and after TL in selected outcomes in the HES group relative to the average change in the non‐HES group. Selected outcomes included serum creatinine, estimated glomerular filtration rate (eGFR), and white blood cell (WBC) count. A total of 195 patients who underwent 278 TL procedures were studied. We found no significant differences in serum creatinine levels and eGFR on Days 1 and 7 after TL procedure between patients who received and those who did not receive HES. The rate of adverse events and overall and early mortality were similar in both groups. Patients with acute myeloid leukemia who received HES had greater WBC reduction when HES was used. Additionally, patients who received HES had improvement in pulmonary leukostasis symptoms.CONCLUSIONHES, used at low doses during TL procedures, was not associated with adverse events previously ascribed to its use as a volume expander.

This special issue surveys recent work and underscores the challenges of psychiatric brain stimulation research with child and adolescent populations. The field of child and adolescent psychopharmacology is replete with examples of potential pitfalls in the assumption that “children are little adults.” Arguably, younger age portends more neurobiological and descriptive heterogeneity in research pursuits and clinical practice. For existing brain stimulation modalities, there are a paucity of translational models to design studies for youth and no well-studied dosing schemes. The long-term positive and negative effects of neuromodulation interventions in youth are unknown. Inherent pragmatic and ethical limitations often present barriers for participant recruitment and will necessitate innovative approaches to study design and team efforts. These challenges are not insurmountable, and sustained efforts will advance the growing field of pediatric neuromodulation.

Mutagenesis screening is a powerful forward genetic approach that has been successfully applied in lower-model organisms to discover genetic factors for biological processes. This phenotype-based approach has yet to be established in vertebrates for probing major human diseases, largely because of the complexity of colony management. Herein, we report a rapid strategy for identifying genetic modifiers of cardiomyopathy (CM). Based on the application of doxorubicin stress to zebrafish insertional cardiac (ZIC) mutants, we identified 4 candidate CM-modifying genes, of which 3 have been linked previously to CM. The long isoform of DnaJ (Hsp40) homolog, subfamily B, member 6b ( dnajb6b(L) ) was identified as a CM susceptibility gene, supported by identification of rare variants in its human ortholog DNAJB6 from CM patients. Mechanistic studies indicated that the deleterious, loss-of-function modifying effects of dnajb6b(L) can be ameliorated by inhibition of ER stress. In contrast, overexpression of dnajb6(L) exerts cardioprotective effects on both fish and mouse CM models. Together, our findings establish a mutagenesis screening strategy that is scalable for systematic identification of genetic modifiers of CM, feasible to suggest therapeutic targets, and expandable to other major human diseases.

AbstractBackgroundIn recent years propranolol has become the treatment of choice for infantile hemangiomas (IHs). There is broad variation in the approach to propranolol initiation in clinical practice. This retrospective study explored the effectiveness of routine pre‐treatment ECG in screening infants being considered for systemic treatment with propranolol.MethodsAll patients seen in the outpatient pediatric dermatology clinics at Oregon Health and Sciences University (OHSU) and The Mayo Clinic Rochester (MCR), as well as those seen in multidisciplinary vascular anomalies clinics, who had ECGs obtained prior to planned initiation of propranolol for treatment of IH from 2008 to 2013, were identified. A total of 162 patients were included in the study.ResultsWe found that 43% (69) of routine ECGs were read as abnormal, leading to 28 formal consultation appointments with pediatric cardiologists. After either formal consultation or informal discussion with cardiology, no patients with initially “abnormal” ECGs were ultimately excluded from treatment with propranolol based on routine ECG findings. Additionally no patients in our cohort experienced an adverse effect during treatment that could have been predicted or prevented by ECG prior to initiation of the propranolol.ConclusionOur findings suggest that routine ECG may not be necessary or helpful in the vast majority of patients treated with propranolol for IHs.

Rationale: Alzheimer’s disease has an unknown pathogenesis; however, cardiovascular risk factors are associated with a higher incidence of Alzheimer’s disease. A defining feature of endothelial dysfunction induced by cardiovascular risk factors is reduced bioavailable endothelial nitric oxide (NO). We previously demonstrated that endothelial NO acts as an important signaling molecule in neuronal tissue. Objective: We sought to determine the relationship between the loss of endothelial NO synthase (eNOS) and tau phosphorylation in neuronal tissue. Methods and Results: We used eNOS knockout ( −/− ) mice as well as an Alzheimer’s disease mouse model, amyloid precursor protein (APP)/PSEN1dE9 +/− (PS1) that lacked eNOS (APP/PS1/eNOS −/− ) to examine expression of tau kinases and tau phosphorylation. Brain tissue from eNOS −/− mice had statistically higher ratios of p25/p35, indicative of increased cyclin-dependent kinase 5 activity as compared with wild-type (n=8, P <0.05). However, tau phosphorylation was unchanged in eNOS −/− mice ( P >0.05). Next, we determined the role of NO in tau pathology in APP/PS1/eNOS −/− . These mice had significantly higher levels of p25, a higher p25/p35 ratio (n=12–14; P <0.05), and significantly higher cyclin-dependent kinase 5 activity (n=4; P <0.001). Importantly, APP/PS1/eNOS −/− mice also had significantly increased tau phosphorylation (n=4–6; P <0.05). No other changes in amyloid pathology, antioxidant pathways, or neuroinflammation were observed in APP/PS1/eNOS −/− mice as compared with APP/PS1 mice. Conclusions: Our data suggests that loss of endothelial NO plays an important role in the generation of p25 and resulting tau phosphorylation in neuronal tissue. These findings provide important new insights into the molecular mechanisms linking endothelial dysfunction with the pathogenesis of Alzheimer’s disease.

Purpose To determine the effects of carfilzomib, lenalidomide, and dexamethasone (KRd) versus lenalidomide and dexamethasone (Rd) on health-related quality of life (HR-QoL) in the Carfilzomib, Lenalidomide, and Dexamethasone Versus Lenalidomide and Dexamethasone for the Treatment of Patients With Relapsed Multiple Myeloma (ASPIRE) trial. Methods Patients with relapsed multiple myeloma were randomly assigned to receive KRd or Rd. The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 and myeloma-specific module were administered at baseline; day 1 of cycles 3, 6, 12, and 18; and after treatment. The Global Health Status/Quality of Life (GHS/QoL) scale and seven subscales (fatigue, nausea and vomiting, pain, physical functioning, role functioning, disease symptoms, and adverse effects of treatment) were compared between groups using a mixed model for repeated measures. The percentages of responders with ≥ 5- or 15-point GHS/QoL improvement at each cycle were compared between groups. Results Baseline questionnaire compliance was excellent (94.1% of randomly assigned patients). KRd patients had higher GHS/QoL scores versus Rd patients over 18 treatment cycles (two-sided P < .001). The minimal important difference was met at cycle 12 (5.6 points) and approached at cycle 18 (4.8 points). There was no difference between groups for the other prespecified subscales from ASPIRE. A higher proportion of KRd patients met the GHS/QoL responder definition (≥ 5-point improvement) with statistical differences at cycle 12 (KRd v Rd patients, 25.5% v 17.4%, respectively) and 18 (KRd v Rd patients, 24.2% v 12.9%, respectively). Conclusion KRd improves GHS/QoL without negatively affecting patient-reported symptoms when compared with Rd. These data further support the benefit of KRd in patients with relapsed multiple myeloma.