Effect of electrode material on the sensitivity of interdigitated electrodes used for Electrical Cell-Substrate Impedance Sensing technology

This study explores the effect of the electrode material on the sensitivity of interdigitated electrodes (IDEs) used in Electrical Cell-Substrate Impedance Sensing (ECIS) technology. This technique is a label-free method to evaluate cellular activity of adherent cells. IDEs of gold (Au), indium tin oxide (ITO) and ITO functionalized with iridium oxide (IrO_x) were characterized with impedance spectroscopy and their interfacial impedances were evaluated in potassium chloride (KCl) solutions. In parallel, ECIS measurements were performed on these three electrode materials during the proliferation of the human breast cancer cell line, MCF-7. The results indicate that the difference in sensitivity to MCF-7 of the three materials might be strongly correlated to their interfacial impedances. We found that ITO electrodes coated with IrO_x show slightly higher sensitivity to MCF-7 breast cancer cells while still offering transparency compared to gold, which is considered the conventional material in ECIS devices.

Diagnostic exome sequencing in children: A survey of parental understanding, experience and psychological impact

Clinical exome sequencing (CES) is increasingly being used as an effective diagnostic tool in the field of pediatric genetics. We sought to evaluate the parental experience, understanding and psychological impact of CES by conducting a survey study of English-speaking parents of children who had diagnostic CES. Parents of 192 unique patients participated. The parent's interpretation of the child's result agreed with the clinician's interpretation in 79% of cases, with more frequent discordance when the clinician's interpretation was uncertain. The majority (79%) reported no regret with the decision to have CES. Most (65%) reported complete satisfaction with the genetic counseling experience, and satisfaction was positively associated with years of genetic counselor (GC) experience. The psychological impact of CES was greatest for parents of children with positive results and for parents with anxiety or depression. The results of this study are important for helping clinicians to prepare families for the possible results and variable psychological impact of CES. The frequency of parental misinterpretation of test results indicates the need for additional clarity in the communication of results. Finally, while the majority of patients were satisfied with their genetic counseling, satisfaction was lower for new GCs, suggesting a need for targeted GC training for genomic testing.

Memory and Brain Amyloid and Tau Effects of a Bioavailable Form of Curcumin in Non-Demented Adults: A Double-Blind, Placebo-Controlled 18-Month Trial

OBJECTIVE

Because curcumin's anti-inflammatory properties may protect the brain from neurodegeneration, we studied its effect on memory in non-demented adults and explored its impact on brain amyloid and tau accumulation using 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile positron emission tomography (FDDNP-PET).

METHODS

Forty subjects (age 51-84 years) were randomized to a bioavailable form of curcumin (Theracurmin® containing 90 mg of curcumin twice daily [N = 21]) or placebo (N = 19) for 18 months. Primary outcomes were verbal (Buschke Selective Reminding Test [SRT]) and visual (Brief Visual Memory Test-Revised [BVMT-R]) memory, and attention (Trail Making A) was a secondary outcome. FDDNP-PET signals (15 curcumin, 15 placebo) were determined in amygdala, hypothalamus, medial and lateral temporal, posterior cingulate, parietal, frontal, and motor (reference) regions. Mixed effects general linear models controlling for age and education, and effect sizes (ES; Cohen's d) were estimated.

RESULTS

SRT Consistent Long-Term Retrieval improved with curcumin (ES = 0.63, p = 0.002) but not with placebo (ES = 0.06, p = 0.8; between-group: ES = 0.68, p = 0.05). Curcumin also improved SRT Total (ES = 0.53, p = 0.002), visual memory (BVMT-R Recall: ES = 0.50, p = 0.01; BVMT-R Delay: ES = 0.51, p = 0.006), and attention (ES = 0.96, p < 0.0001) compared with placebo (ES = 0.28, p = 0.1; between-group: ES = 0.67, p = 0.04). FDDNP binding decreased significantly in the amygdala with curcumin (ES = -0.41, p = 0.04) compared with placebo (ES = 0.08, p = 0.6; between-group: ES = 0.48, p = 0.07). In the hypothalamus, FDDNP binding did not change with curcumin (ES = -0.30, p = 0.2), but increased with placebo (ES = 0.26, p = 0.05; between-group: ES = 0.55, p = 0.02).

CONCLUSIONS

Daily oral Theracurmin may lead to improved memory and attention in non-demented adults. The FDDNP-PET findings suggest that symptom benefits are associated with decreases in amyloid and tau accumulation in brain regions modulating mood and memory.

FT-IR and NMR structural markers for thiazole-based γ-peptide foldamers

Nuclear magnetic resonance (NMR) spectroscopy has been established as a potent method for the determination of foldamer structures in solution. However, the NMR techniques could be limited by averaging, so additional experimental techniques are often needed to fully endorse the folding properties of a sequence. We have recently demonstrated that oligo-γ-peptides composed of 4-amino(methyl)-1,3-thiazole-5-carboxylic acids (ATCs) adopt an original helical fold stabilized by hydrogen bonds forming C₉ pseudocycles. The main objective of the present work is to reinvestigate the folding of ATC oligomer 1 in order to identify reliable FT-IR and NMR structural markers that are of value for tracking the degree of organization of ATC-based peptides.

FDDNP-PET Tau Brain Protein Binding Patterns in Military Personnel with Suspected Chronic Traumatic Encephalopathy1

BACKGROUND

Our group has shown that in vivo tau brain binding patterns from FDDNP-PET scans in retired professional football players with suspected chronic traumatic encephalopathy differ from those of tau and amyloid aggregate binding observed in Alzheimer's disease (AD) patients and cognitively-intact controls.

OBJECTIVE

To compare these findings with those from military personnel with histories of mild traumatic brain injury(mTBI).

METHODS

FDDNP-PET brain scans were compared among 7 military personnel and 15 retired players with mTBI histories and cognitive and/or mood symptoms, 24 AD patients, and 28 cognitively-intact controls. Nonparametric ANCOVAs with Tukey-Kramer adjusted post-hoc comparisons were used to test for significant differences in regional FDDNP binding among subject groups.

RESULTS

FDDNP brain binding was higher in military personnel compared to controls in the amygdala, midbrain, thalamus, pons, frontal and anterior and posterior cingulate regions (p < 0.01-0.0001). Binding patterns in the military personnel were similar to those of the players except for the amygdala and striatum (binding higher in players; p = 0.02-0.003). Compared with the AD group, the military personnel showed higher binding in the midbrain (p = 0.0008) and pons (p = 0.002) and lower binding in the medial temporal, lateral temporal, and parietal regions (all p = 0.02).

CONCLUSION

This first study of in vivo tau and amyloid brain signals in military personnel with histories of mTBI shows binding patterns similar to those of retired football players and distinct from the binding patterns in AD and normal aging, suggesting the potential value of FDDNP-PET for early detection and treatment monitoring in varied at-risk populations.

In Vivo Brain Plaque and Tangle Burden Mediates the Association Between Diastolic Blood Pressure and Cognitive Functioning in Nondemented Adults

OBJECTIVE

Growing evidence supports an association between increased blood pressure and: (a) poor cognitive performance in older adults, and (b) various biomarkers of increased Alzheimer's disease (AD) neuropathology. The objective of this study was to determine whether systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly associated with cognitive functioning in non-demented adults, and to examine in vivo AD pathology as a possible mediator of this association.

METHODS

Positron emission tomography (PET) scans with 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile (FDDNP) provide in vivo measurements of plaque and tangle burden. A total of 101 non-demented older subjects with blood pressure data and FDDNP-PET scans were drawn from a larger study of predictors of cognitive decline. A neuropsychological test battery was used to compute "global cognitive scores" (averaged across five key domains), which served as an index of general cognitive functioning.

RESULTS

Higher DBP (but not SBP) was significantly associated with lower cognitive scores, controlling for age, sex, antihypertensive medication use, and ApoE genotype (η2 = 0.06). However, this relationship was no longer significant after introducing FDDNP-PET binding as an additional covariate in the statistical models. In vivo plaque and tangle burden accounted for over 30% of the observed association between higher DBP and poorer cognitive performance.

CONCLUSIONS

By suggesting a mediation of the relationship between DBP and cognitive functioning by FDDNP-PET binding, this study advances our understanding of some potential predictors of cognitive decline in non-demented adults, and underscores the importance of devising early multimodal interventions to more effectively combat degenerative brain disorders.

Kinase profiling of liposarcomas using RNAi and drug screening assays identified druggable targets

BACKGROUND

Liposarcoma, the most common soft tissue tumor, is understudied cancer, and limited progress has been made in the treatment of metastatic disease. The Achilles heel of cancer often is their kinases that are excellent therapeutic targets. However, very limited knowledge exists of therapeutic critical kinase targets in liposarcoma that could be potentially used in disease management.

METHODS

Large RNAi and small-molecule tyrosine kinase inhibitor screens were performed against the proliferative capacity of liposarcoma cell lines of different subtypes. Each small molecule inhibitor was either FDA approved or in a clinical trial.

RESULTS

Screening assays identified several previously unrecognized targets including PTK2 and KIT in liposarcoma. We also observed that ponatinib, multi-targeted tyrosine kinase inhibitor, was the most effective drug with anti-growth effects against all cell lines. In vitro assays showed that ponatinib inhibited the clonogenic proliferation of liposarcoma, and this anti-growth effect was associated with apoptosis and cell cycle arrest at the G0/G1 phase as well as a decrease in the KIT signaling pathway. In addition, ponatinib inhibited in vivo growth of liposarcoma in a xenograft model.

CONCLUSIONS

Two large-scale kinase screenings identified novel liposarcoma targets and a FDA-approved inhibitor, ponatinib with clear anti-liposarcoma activity highlighting its potential therapy for treatment of this deadly tumor.

Effect of electrode material on the sensitivity of interdigitated electrodes used for Electrical Cell-Substrate Impedance Sensing technology

This study explores the effect of the electrode material on the sensitivity of interdigitated electrodes (IDEs) used in Electrical Cell-Substrate Impedance Sensing (ECIS) technology. This technique is a label-free method to evaluate cellular activity of adherent cells. IDEs of gold (Au), indium tin oxide (ITO) and ITO functionalized with iridium oxide (IrO_x) were characterized with impedance spectroscopy and their interfacial impedances were evaluated in potassium chloride (KCl) solutions. In parallel, ECIS measurements were performed on these three electrode materials during the proliferation of the human breast cancer cell line, MCF-7. The results indicate that the difference in sensitivity to MCF-7 of the three materials might be strongly correlated to their interfacial impedances. We found that ITO electrodes coated with IrO_x show slightly higher sensitivity to MCF-7 breast cancer cells while still offering transparency compared to gold, which is considered the conventional material in ECIS devices.

The Renin-Angiotensin-Aldosterone System in Greyhounds and Non-Greyhound Dogs

Background

The renin‐angiotensin‐aldosterone system (RAAS) regulates blood pressure, electrolyte homeostasis, and renal function. Blood pressure, serum sodium concentrations, and urinary albumin excretion are higher in Greyhounds than other purebred and mixed‐breed dogs.

Hypothesis

Alterations in the RAAS in Greyhounds are associated with hemodynamic and clinicopathologic differences observed in the breed.

Animals

Clinically healthy Greyhound and non‐Greyhound dogs consecutively enrolled as blood donors (n = 20/group).

Methods

Prospective study. Standard chemical analysis was performed on serum and urine. Serum angiotensin‐converting enzyme (ACE) activity was determined by fluorometric assay. All other RAAS hormones were determined by radioimmunoassay. Symmetric dimethylarginine (SDMA) was measured by immunoassay. Measurements were compared to blood pressure and urine albumin concentration. Data are presented as mean ± SD or median, range.

Results

Serum creatinine (1.5 ± 0.2 vs 1.0 ± 0.1 mg/dL, P < .001), sodium (149, 147–152 vs 148, 146–150 mEq/L, P = .017), and SDMA (16.1 ± 2.9 vs 12.2 ± 1.8 μg/dL, P < .001) were significantly higher in Greyhounds versus non‐Greyhounds, respectively. Plasma renin activity (0.69, 0.10–1.93 vs 0.65, 0.27–2.93 ng/mL/h, P = .60) and ACE activity (4.5, 2.1–8.5 vs 4.6, 2.1–11.4 activity/mL; P = .77) were similar between groups and did not correlate with higher systolic pressures and albuminuria in Greyhounds. Plasma aldosterone concentration was significantly lower in Greyhounds versus non‐Greyhounds (11, 11–52 vs 15, 11–56 pg/mL, respectively, P = .002).

Conclusions and clinical importance

Basal RAAS activation did not differ between healthy Greyhounds and non‐Greyhounds. Lower aldosterone concentration in Greyhounds is an appropriate physiologic response to higher serum sodium concentration and blood pressure, suggesting that angiotensin II effects in the renal tubule predominate over those of aldosterone.

Modular bioink for 3D printing of biocompatible hydrogels: sol–gel polymerization of hybrid peptides and polymers

Inorganic polymerization as a cross-linking method for 3D printing of PEG–peptide hydrogels.

SEOM Clinical Guideline in ovarian cancer (2016)

Despite remarkable advances in the knowledge of molecular biology and treatment, ovarian cancer (OC) is the first cause of death due to gynecological cancer and the fifth cause of death for cancer in women in Spain. The aim of this guideline is to summarize the current evidence and to give evidence-based recommendations for clinical practice.

Wolbachia-mediated protection against viruses in the invasive pest Drosophila suzukii

The maternally inherited bacterium Wolbachia is well known for spreading in natural populations by manipulating the reproduction of its arthropod hosts, but can also have mutualist effects that increase host fitness. In mosquitoes and Drosophila some Wolbachia strains can lead to an increase in survival of virus-infected insects, and in most cases this is associated with reduced accumulation of the virus in host tissues. We investigated if the Wolbachia strain wSuz, which naturally infects Drosophila suzukii, is able to confer protection against Drosophila C virus and Flock House virus in different host genetic backgrounds. We found that this strain can increase host survival upon infection with these two viruses. In some cases this effect was associated with lower viral titres, suggesting that it confers resistance to the viruses rather than allowing the flies to tolerate infection. Our results indicate that, in D. suzukii, the antiviral protection provided by Wolbachia is not correlated to its density as found in other Drosophila species. This study demonstrates a phenotypic effect induced by wSuz on its native host which could explain its maintenance in natural populations of D. suzukii.

FGF2 from Marrow Microenvironment Promotes Resistance to FLT3 Inhibitors in Acute Myeloid Leukemia

Potent FLT3 inhibitors, such as quizartinib (AC220), have shown promise in treating acute myeloid leukemia (AML) containing FLT3 internal tandem duplication (ITD) mutations. However, responses are not durable and resistance develops within months. In this study, we outline a two-step model of resistance whereby extrinsic microenvironmental proteins FLT3 ligand (FL) and fibroblast growth factor 2 (FGF2) protect FLT3-ITD+ MOLM14 cells from AC220, providing time for subsequent accumulation of ligand-independent resistance mechanisms. FL directly attenuated AC220 inhibition of FLT3, consistent with previous reports. Conversely, FGF2 promoted resistance through activation of FGFR1 and downstream MAPK effectors; these resistant cells responded synergistically to combinatorial inhibition of FGFR1 and FLT3. Removing FL or FGF2 from ligand-dependent resistant cultures transiently restored sensitivity to AC220, but accelerated acquisition of secondary resistance via reactivation of FLT3 and RAS/MAPK signaling. FLT3-ITD AML patients treated with AC220 developed increased FGF2 expression in marrow stromal cells, which peaked prior to overt clinical relapse and detection of resistance mutations. Overall, these results support a strategy of early combination therapy to target early survival signals from the bone marrow microenvironment, in particular FGF2, to improve the depth of response in FLT3-ITD AML. Cancer Res; 76(22); 6471-82. ©2016 AACR.