The use of 7-amino actinomycin D in identifying apoptosis: simplicity of use and broad spectrum of application compared with other techniques

The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.     

Autonomic dysfunction in Parkinson's disease: A prospective cohort study

Background : Dysautonomia is a frequent and disabling complication of PD, with an estimated prevalence of 30‐40% and a significant impact on the quality of life. Objectives : To evaluate the rate of progression of dysautonomia and, in particular, orthostatic hypotension, in a cohort of unselected PD patients, and assess the extent to which the progression of dysautonomia affects activities of daily living, health‐related quality of life, and health care utilization in PD. Methods : We recruited 131 consecutive patients into a 12‐month, prospective, observational cohort study. Clinical measures included the International Parkinson and Movement Disorder Society/UPDRS, the Scale for Outcomes in Parkinson Disease‐Autonomic, the Orthostatic Hypotension Symptoms Assessment, and orthostatic blood pressure measurements. Health care utilization was quantified as the number of hospitalizations, emergency room visits, and outpatient clinic evaluations. Results : The overall severity of autonomic symptoms, as measured by the the Orthostatic Hypotension Symptoms Assessment total score, worsened by 20% over 12 months (P < 0.001), with an overall increase in orthostatic hypotension prevalence from 31.1% to 46.7% (P < 0.001). Worsening of autonomic symptoms was independently associated with deterioration in daily living activities (P = 0.021) and health‐related quality of life (P = 0.025) adjusting for disease duration, cognitive impairment, and motor severity. Regardless of symptomatic status, orthostatic hypotension was associated with greater deterioration in daily living activities, health care utilization, and falls (P ≤ 0.009) compared to patients without orthostatic hypotension. Conclusions : The severity of autonomic symptoms progressed by 20% over 1 year and was independently associated with impairments in daily living activities and health‐related quality of life. Symptomatic and asymptomatic orthostatic hypotension were both associated with increased prevalence of falls and health care utilization. © 2017 International Parkinson and Movement Disorder Society     

Evaluation of [18F]-JNJ-64326067-AAA tau PET tracer in humans

The [¹⁸F]-JNJ-64326067-AAA ([¹⁸F]-JNJ-067) tau tracer was evaluated in healthy older controls (HCs), mild cognitive impairment (MCI), Alzheimer’s disease (AD), and progressive supranuclear palsy (PSP) participants. Seventeen subjects (4 HCs, 5 MCIs, 5 ADs, and 3 PSPs) received a [¹¹C]-PIB amyloid PET scan, and a tau [¹⁸F]-JNJ-067 PET scan 0-90 minutes post-injection. Only MCIs and ADs were amyloid positive. The simplified reference tissue model, Logan graphical analysis distribution volume ratio, and SUVR were evaluated for quantification. The [¹⁸F]-JNJ-067 tau signal relative to the reference region continued to increase to 90 min, indicating the tracer had not reached steady state. There was no significant difference in any bilateral ROIs for MCIs or PSPs relative to HCs; AD participants showed elevated tracer relative to controls in most cortical ROIs (P < 0.05). Only AD participants showed elevated retention in the entorhinal cortex. There was off-target signal in the putamen, pallidum, thalamus, midbrain, superior cerebellar gray, and white matter. [¹⁸F]-JNJ-067 significantly correlated (p < 0.05) with Mini-Mental State Exam in entorhinal cortex and temporal meta regions. There is clear binding of [¹⁸F]-JNJ-067 in AD participants. Lack of binding in HCs, MCIs and PSPs suggests [¹⁸F]-JNJ-067 may not bind to low levels of AD-related tau or 4 R tau.