Enumeration of islets by nuclei counting and light microscopic analysis

Author Manuscript 2011 May 1.Islet enumeration in impure preparations by conventional dithizone staining and visual counting is inaccurate and operator dependent. We examined nuclei counting for measuring the total number of cells in islet preparations, and we combined it with morphological analysis by light microscopy (LM) for estimating the volume fraction of islets in impure preparations. Cells and islets were disrupted with lysis solution and shear, and accuracy of counting successively diluted nuclei suspensions was verified with (1) visual counting in a hemocytometer after staining with crystal violet, and automatic counting by (2) aperture electrical resistance measurement and (3) flow cytometer measurement after staining with 7-aminoactinomycin-D. DNA content averaged 6.5 and 6.9 pg of DNA per cell for rat and human islets, respectively, in agreement with literature estimates. With pure rat islet preparations, precision improved with increasing counts, and samples with about greater than or equal to 160 islets provided a coefficient of variation of about 6%. Aliquots of human islet preparations were processed for LM analysis by stereological point counting. Total nuclei counts and islet volume fraction from LM analysis were combined to obtain the number of islet equivalents (IEs). Total number of IE by the standard method of dithizone staining/manual counting was overestimated by about 90% compared with LM/nuclei counting for 12 freshly isolated human islet research preparations. Nuclei counting combined with islet volume fraction measurements from LM is a novel method for achieving accurate islet enumeration.National Institutes of Health (U.S.) (Grant NCRR ICR U4Z 16606)National Institutes of Health (U.S.) (Grant R01-DK063108-01A1)National Institutes of Health (U.S.) (Grant NCRR ICR U42 RR0023244-01)Joslin Diabetes and Endocrinology Research Center (Grant DK36836)Diabetes Research & Wellness FoundationJuvenile Diabetes Research Foundation International (Islet Transplantation, Harvard Medical School

Self-control interventions for children under age 10 for improving self-control and delinquency and problem behaviors

Self-control improvement programs are intended to serve many purposes, most notably improving self-control. Yet, interventions such as these often aim to reduce delinquency and problem behaviors. However, there is currently no summary statement available regarding whether or not these programs are effective in improving self-control and reducing delinquency and problem behaviors. The main objective of this review is to assess the available research evidence on the effect of self-control improvement programs on self-control and delinquency and problem behaviors. In addition to investigating the overall effect of early selfcontrol improvement programs, this review will examine, to the extent possible, the context in which these programs may be most successful. The studies included in this systematic review indicate that self-control improvement programs are an effective intervention for improving self-control and reducing delinquency and problem behaviors, and that the effect of these programs appears to be rather robust across various weighting procedures, and across context, outcome source, and based on both published and unpublished data

Tracking dyspnea up to supplemental oxygen prescription among patients with pulmonary fibrosis

Abstract Background Dyspnea is the hallmark symptom of pulmonary fibrosis. Supplemental oxygen (O2) is prescribed to many patients with pulmonary fibrosis in hopes of alleviating dyspnea and improving physical functioning. We used response data from the University of California San Diego Shortness of Breath Questionnaire (UCSD) which was administered monthly in the context of a longitudinal, observational study to plot a rich trajectory for dyspnea over time in patients with pulmonary fibrosis. We used other data from that study to identify clinical predictors of being prescribed O2 and to provide additional information for how UCSD scores could be used for clinical purposes. Methods We used linear mixed-effects models and multivariate Cox proportional hazards to model change in dyspnea scores over time and to identify significant predictors of time-to-O2-prescription among a pool of clinically-meaningful candidate variables. In the longitudinal study, all decisions, including whether or not to prescribe O2, were made by subjects’ treating physicians, not members of the research team. Results One-hundred ninety-four subjects with pulmonary fibrosis completed more than one UCSD or were prescribed O2 at some point during the follow-up period (N = 43). Twenty-eight of the 43 had analyzable, longitudinal data and contribute data to the longitudinal UCSD analyses. All 43 were included in the time-to-O2-prescription analyses. Subjects prescribed O2 had more severe dyspnea at enrollment (38.4 ± 19.6 vs. 22.6 ± 18.7, p < 0.0001) and a steeper increase in UCSD scores over time (slope = 1.18 ± 0.53 vs. 0.24 ± 0.09 points per month, p = 0.02) than subjects not prescribed O2. Controlling for baseline UCSD score and FVC%, subjects with a clinical summary diagnosis of idiopathic pulmonary fibrosis (IPF) were far more likely to be prescribed O2 than subjects with other forms of pulmonary fibrosis (hazard ratio = 4.85, (2.19, 10.74), p < 0.0001). Conclusions Baseline dyspnea and rise in dyspnea over time predict timing of O2 prescription. Accounting for disease severity, patients with IPF are more likely than patients with other forms of pulmonary fibrosis to be prescribed O2. UCSD scores provide clinically useful information; frequent administration could yield timely data on changes in disease status in patients with pulmonary fibrosis. Trial registration The longitudinal study is registered on ClinicalTrials.gov ( NCT01961362 ). Registered October 9, 2013