Tc-99m pyrophosphate imaging of poloxamer-treated electroporated skeletal muscle in an in vivo rat model

Objective: This study investigates whether 99mTc pyrophosphate (PYP) imaging provides a quantitative non-invasive assessment of the extent of electroporation injury, and of the effect of poloxamer in vivo on electroporated skeletal muscle. Methods: High-voltage electrical shock was used to produce electroporation injury in an anesthetized rat\u27s hind limb. In each experiment, the injured limb was treated intravenously by either poloxamer-188, dextran, or saline, and subsequently imaged with 99mTc PYP. The radiotracer\u27s temporal behavior among the experimental groups was compared using curve fitting of time-activity curves from the dynamic image data. Results: The washout kinetics of 99mTc PYP changed in proportion to the electric current magnitude that produced electroporation. Also, 99mTc PYP washout from electroporated muscle differed between poloxamer-188 treatment and saline treatment. Finally, 10-kDa dextran treatment of electroporated muscle altered 99mTc PYP washout less than poloxamer-188 treatment. Conclusions: Behavior of 99mTc PYP in electroporated muscle appears to be an indicator of the amount of electroporation injury. Compared to saline, intravenous polaxamer-188 treatment reduced the amount of 99mTc PYP uptake. Coupled to results showing poloxamer-188 seals ruptured cellular membranes, lessens the extent of electroporation injury and improves cell viability, 99mTc PYP imaging appears to be a useful in vivo monitoring tool for the extent of electroporation injury. © 2006 Elsevier Ltd and ISBI

Effects of adjunctive eslicarbazepine acetate on serum lipids in patients with partial-onset seizures: Impact of concomitant statins and enzyme-inducing antiepileptic drugs.

PURPOSE: To evaluate the effects of eslicarbazepine acetate (ESL) on lipid metabolism and to determine whether reduced statin exposure during ESL therapy has clinical consequences. SUBJECTS AND METHODS: We conducted a post-hoc analysis of pooled data for serum lipids (laboratory values) from three phase III, multicenter, randomized, double-blind, placebo-controlled trials of adjunctive ESL therapy (400, 800, or 1200 mg once daily) in patients with treatment-refractory partial-onset seizures. Changes from baseline in serum lipid levels were analyzed according to use of statins and/or enzyme-inducing antiepileptic drugs (EIAEDs) during the baseline period. KEY FINDINGS: In total, 426 and 1021 placebo- and ESL-treated patients, respectively, were included in the analysis. With regard to the changes from baseline in serum concentrations, there were statistically significant differences between the placebo and ESL 1200 mg QD groups, for both total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C), but the effect sizes were small (+4.1 mg/dL and +1.8 mg/dL, respectively). A small but significant difference in low-density lipoprotein cholesterol (LDL-C; -5.0 mg/dL) was observed between the ESL 400 mg QD group and the placebo group. In patients not taking a concomitant EIAED, there were no changes with ESL 400 mg QD, but modest and statistically significant increases in cholesterol fractions (TC, LDL-C and HDL-C) with ESL 800 mg QD (/dL) and ESL 1200 mg QD (/dL). ESL had no consistent effect on lipids in patients taking a concomitant EIAED. In patients taking statins during baseline, there were no clinically relevant changes in serum lipids during use of ESL, although the subgroups were small. SIGNIFICANCE: These results suggest that ESL does not appear to have clinically significant effects on serum lipids, nor does the pharmacokinetic interaction between ESL and statins have an impact on serum lipid concentrations

Two successive calcium-dependent transitions mediate membrane binding and oligomerization of daptomycin and the related antibiotic A54145

The final publication is available at Elsevier via http://doi.org/10.1016/j.bbamem.2016.05.020 © 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Daptomycin and A54145 are homologous lipopeptide antibiotics that permeabilize the cell membranes of Gram-positive bacteria. Membrane permeabilization depends on the presence of both phosphatidylglycerol (PG) and calcium, and it involves the formation of oligomeric transmembrane pores that consist of approximately 6-8 subunits. We here show that each lipopeptide molecule binds two calcium ions in separable, successive steps. The first calcium ion causes the lipopeptide molecule to bind to the target membrane, and likely to form a loosely associated oligomer. Higher calcium concentrations induce binding of a second ion, which produces the more tightly associated and more deeply membrane-inserted final, functional form of the oligomer. Both calcium dependent steps are accompanied by fluorescence signals that indicate transition of specific amino acid residues into less polar environments, suggestive of insertion into the target membrane. Our findings agree with the earlier observation that two of the four acidic amino acid residues in the daptomycin molecule are essential for antibacterial activity. (C) 2016 Elsevier B.V. All rights reserved.This study was supported by operating grants by NSERC to Scott Taylor (155283-2012) and Michael Palmer (250265-2013)

Agitation in cognitive disorders: International Psychogeriatric Association provisional consensus clinical and research definition

Background: Agitation is common across neuropsychiatric disorders and contributes to disability, institutionalization, and diminished quality of life for patients and their caregivers. There is no consensus definition of agitation and no widespread agreement on what elements should be included in the syndrome. The International Psychogeriatric Association formed an Agitation Definition Work Group (ADWG) to develop a provisional consensus definition of agitation in patients with cognitive disorders that can be applied in epidemiologic, non-interventional clinical, pharmacologic, non-pharmacologic interventional, and neurobiological studies. A consensus definition will facilitate communication and cross-study comparison and may have regulatory applications in drug development programs. Methods: The ADWG developed a transparent process using a combination of electronic, face-to-face, and survey-based strategies to develop a consensus based on agreement of a majority of participants. Nine-hundred twenty-eight respondents participated in the different phases of the process. Results: Agitation was defined broadly as: (1) occurring in patients with a cognitive impairment or dementia syndrome; (2) exhibiting behavior consistent with emotional distress; (3) manifesting excessive motor activity, verbal aggression, or physical aggression; and (4) evidencing behaviors that cause excess disability and are not solely attributable to another disorder (psychiatric, medical, or substance-related). A majority of the respondents rated all surveyed elements of the definition as strongly agree or somewhat agree (68-88 across elements). A majority of the respondents agreed that the definition is appropriate for clinical and research applications. Conclusions: A provisional consensus definition of agitation has been developed. This definition can be used to advance interventional and non-interventional research of agitation in patients with cognitive impairment. Copyright © International Psychogeriatric Association 2014

Leukocyte surface biomarkers implicate deficits of innate immunity in sporadic Alzheimer\u27s disease

Introduction: Blood-based diagnostics and prognostics in sporadic Alzheimer\u27s disease (AD) are important for identifying at-risk individuals for therapeutic interventions. Methods: In three stages, a total of 34 leukocyte antigens were examined by flow cytometry immunophenotyping. Data were analyzed by logistic regression and receiver operating characteristic (ROC) analyses. Results: We identified leukocyte markers differentially expressed in the patients with AD. Pathway analysis revealed a complex network involving upregulation of complement inhibition and downregulation of cargo receptor activity and Aβ clearance. A proposed panel including four leukocyte markers – CD11c, CD59, CD91, and CD163 – predicts patients’ PET Aβ status with an area under the curve (AUC) of 0.93 (0.88 to 0.97). CD163 was the top performer in preclinical models. These findings have been validated in two independent cohorts. Conclusion: Our finding of changes on peripheral leukocyte surface antigens in AD implicates the deficit in innate immunity. Leukocyte-based biomarkers prove to be both sensitive and practical for AD screening and diagnosis

A Whole Cell Assay to Measure Caspase-6 Activity by Detecting Cleavage of Lamin A/C

Caspase-6 is a cysteinyl protease implicated in neurodegenerative conditions including Alzheimer's and Huntington's disease making it an attractive target for therapeutic intervention. A greater understanding of the role of caspase-6 in disease has been hampered by a lack of suitable cellular assays capable of specifically detecting caspase-6 activity in an intact cell environment. This is mainly due to the use of commercially available peptide substrates and inhibitors which lack the required specificity to facilitate development of this type of assay. We report here a 384-well whole-cell chemiluminescent ELISA assay that monitors the proteolytic degradation of endogenously expressed lamin A/C during the early stages of caspase-dependent apoptosis. The specificity of lamin A/C proteolysis by caspase-6 was demonstrated against recombinant caspase family members and further confirmed in genetic deletion studies. In the assay, plasma membrane integrity remained intact as assessed by release of lactate dehydrogenase from the intracellular environment and the exclusion of cell impermeable peptide inhibitors, despite the induction of an apoptotic state. The method described here is a robust tool to support drug discovery efforts targeting caspase-6 and is the first reported to specifically monitor endogenous caspase-6 activity in a cellular context

Effect of Endoscopic Sphincterotomy for Suspected Sphincter of Oddi Dysfunction on Pain-Related Disability Following Cholecystectomy: The EPISOD Randomized Clinical Trial

Abdominal pain after cholecystectomy is common and may be attributed to sphincter of Oddi dysfunction. Management often involves endoscopic retrograde cholangiopancreatography (ERCP) with manometry and sphincterotomy

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder