3,179 research outputs found

    Liposomal delivery of hydrophobic RAMBAs provides good bioavailability and significant enhancement of retinoic acid signalling in neuroblastoma tumour cells

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    Retinoid treatment is employed during residual disease treatment in neuroblastoma, where the aim is to induce neural differentiation or death in tumour cells. However, although therapeutically effective, retinoids have only modest benefits and suffer from poor pharmacokinetic properties. In vivo, retinoids induce CYP26 enzyme production in the liver, enhancing their own rapid metabolic clearance, while retinoid resistance in tumour cells themselves is considered to be due in part to increased CYP26 production. Retinoic acid metabolism blocking agents (RAMBAs), which inhibit CYP26 enzymes, can improve retinoic acid pharmacokinetics in pre-clinical neuroblastoma models. Here we demonstrate that in cultured neuroblastoma tumour cells, RAMBAs enhance retinoic acid action as seen by morphological differentiation, AKT signalling and suppression of MYCN protein. Although active as retinoid enhancers, these RAMBAs are highly hydrophobic and their effective delivery in humans will be very challenging. Here we demonstrate that such RAMBAs can be loaded efficiently into cationic liposomal particles, where the RAMBAs achieve good bioavailability and activity in cultured tumour cells. This demonstrates the efficacy of RAMBAs in enhancing retinoid signaling in neuroblastoma cells and shows for the first time that liposomal delivery of hydrophobic RAMBAs is a viable approach, providing novel opportunities for their delivery and application in humans

    Regenerative medicine therapy: adipose derived extracellular vesicles in viral myocarditis

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    Objective: Myocarditis, inflammation of the heart muscle, is an autoimmune heart disease that can be caused by viruses, bacteria and toxins. Myocarditis can lead to dilated cardiomyopathy (DCM) and heart failure. Currently there are no disease-specific therapies for treating myocarditis or preventing progression to DCM. Adipose Extracellular Vesicles (AEVs) are lipid bilayer nanoparticles that are released into the outside environment of adipocytes and provide promising regenerative potential for inflammatory diseases like myocarditis. Methods: Lipoaspirate was obtained from women and men and AEVs isolated from the lipoaspirate using tangential flow filtration. We injected wild type male BALB/c mice with 250uL AEVs (1×10^10 EV/mL) intraperitoneally or sucrose control on day -1, 0, 1 with viral infection on day 0. Mice were harvested on day 10 post infection at the peak of myocarditis. Results: We found that male mice treated with AEVs from a female patient had a significantly higher body weight (p=0.0003), less calcification in the gut (p=0.001) and less myocardial inflammation (p=0.007) than controls. Mouse hearts analyzed by qRT-PCR revealed that AEV treated mice had significantly lower relative gene expression of cell markers for total immune cells (CD45, p=0.002), macrophages (CD11b, p=0.002, F4/80, p=0.0004); specifically M2 macrophages (Chi313, p=0.003), as well as CD3+ (p=0.007) and CD4+ T cells (p=0.01) than controls. Additionally, we found that mice treated with AEVs from a male patient also had significantly less myocardial inflammation (p=0.01). Conclusion: AEVs could provide an innovative therapy to reduce cardiac inflammation and decrease the risk of developing DCM following myocarditis

    Microwave Imaging for Neoadjuvant Chemotherapy Monitoring: Initial Clinical Experience

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    Introduction: Microwave tomography recovers images of tissue dielectric properties, which appear to be specific for breast cancer, with low-cost technology that does not present an exposure risk, suggesting the modality may be a good candidate for monitoring neoadjuvant chemotherapy. Methods: Eight patients undergoing neoadjuvant chemotherapy for locally advanced breast cancer were imaged longitudinally five to eight times during the course of treatment. At the start of therapy, regions of interest (ROIs) were identified from contrast-enhanced magnetic resonance imaging studies. During subsequent microwave examinations, subjects were positioned with their breasts pendant in a coupling fluid and surrounded by an immersed antenna array. Microwave property values were extracted from the ROIs through an automated procedure and statistical analyses were performed to assess short term (30 days) and longer term (four to six months) dielectric property changes. Results: Two patient cases (one complete and one partial response) are presented in detail and demonstrate changes in microwave properties commensurate with the degree of treatment response observed pathologically. Normalized mean conductivity in ROIs from patients with complete pathological responses was significantly different from that of partial responders (P value = 0.004). In addition, the normalized conductivity measure also correlated well with complete pathological response at 30 days (P value = 0.002). Conclusions: These preliminary findings suggest that both early and late conductivity property changes correlate well with overall treatment response to neoadjuvant therapy in locally advanced breast cancer. This result is consistent with earlier clinical outcomes that lesion conductivity is specific to differentiating breast cancer from benign lesions and normal tissue

    Association Between Schizophrenia-Related Polygenic Liability and the Occurrence and Level of Mood-Incongruent Psychotic Symptoms in Bipolar Disorder

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    Importance Bipolar disorder (BD) overlaps schizophrenia in its clinical presentation and genetic liability. Alternative approaches to patient stratification beyond current diagnostic categories are needed to understand the underlying disease processes/mechanisms. Objectives To investigate the relationship between common-variant liability for schizophrenia, indexed by polygenic risk scores (PRS) and psychotic presentations of BD, using clinical descriptions which consider both occurrence and level of mood-incongruent psychotic features. Design Case-control design: using multinomial logistic regression, to estimate differential associations of PRS across categories of cases and controls. Settings & Participants 4399 BD cases, 2966 (67%) female, mean age-at-interview 46 [sd 12] years, from the BD Research Network (BDRN) were included in the final analyses. For comparison genotypic data for 4976 schizophrenia cases and 9012 controls from the Type-1 diabetes genetics consortium and Generation Scotland were included. Exposure Standardised PRS, calculated using alleles with an association p-value threshold < 0.05 in the second Psychiatric Genomics Consortium genome-wide association study of schizophrenia, adjusted for the first 10 population principal components and genotyping-platform. Main outcome measure Multinomial logit models estimated PRS associations with BD stratified by (1) Research Diagnostic Criteria (RDC) BD subtypes (2) Lifetime occurrence of psychosis.(3) Lifetime mood-incongruent psychotic features and (4) ordinal logistic regression examined PRS associations across levels of mood-incongruence. Ratings were derived from the Schedule for Clinical Assessment in Neuropsychiatry interview (SCAN) and the Bipolar Affective Disorder Dimension Scale (BADDS). Results Across clinical phenotypes, there was an exposure-response gradient with the strongest PRS association for schizophrenia (RR=1.94, (95% C.I. 1.86, 2.01)), then schizoaffective BD (RR=1.37, (95% C.I. 1.22, 1.54)), BD I (RR= 1.30, (95% C.I. 1.24, 1.36)) and BD II (RR=1.04, (95% C.I. 0.97, 1.11)). Within BD cases, there was an effect gradient, indexed by the nature of psychosis, with prominent mood-incongruent psychotic features having the strongest association (RR=1.46, (95% C.I. 1.36, 1.57)), followed by mood-congruent psychosis (RR= 1.24, (95% C.I. 1.17, 1.33)) and lastly, BD cases with no history of psychosis (RR=1.09, (95% C.I. 1.04, 1.15)). Conclusion We show for the first time a polygenic-risk gradient, across schizophrenia and bipolar disorder, indexed by the occurrence and level of mood-incongruent psychotic symptoms

    Postpartum psychosis in bipolar disorder: no evidence of association with personality traits, cognitive style or affective temperaments

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    Background: Bipolar disorder has been associated with several personality traits, cognitive styles and affective temperaments. Women who have bipolar disorder are at increased risk of experiencing postpartum psychosis, however little research has investigated these traits and temperaments in relation to postpartum psychosis. The aim of this study is to establish whether aspects of personality, cognitive style and affective temperament that have been associated with bipolar disorder also confer vulnerability to postpartum psychosis over and above their known association with bipolar disorder. Methods: Personality traits (neuroticism, extraversion, schizotypy and impulsivity), cognitive styles (low self-esteem and dysfunctional attitudes) and affective temperaments (including cyclothymic and depressive temperaments) were compared between two groups of parous women with DSM-IV bipolar I disorder: i) 284 with a lifetime history of postpartum psychosis within 6 weeks of delivery (PP group), ii) 268 without any history of mood episodes with onset during pregnancy or within 6 months of delivery (no perinatal mood episode, No PME group). Results: After controlling for current mood state, and key demographic, clinical and pregnancy-related variables, there were no statistically significant differences between the PP and No PME groups on any of the personality, cognitive style or affective temperament measures. Conclusions: Personality traits, cognitive styles and affective temperaments previously shown to be associated with bipolar disorder in general were not specifically associated with the occurrence of postpartum psychosis. These factors may not be relevant for predicting risk of postpartum psychosis in women with bipolar disorder

    Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

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    The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
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