Nanoparticles obtained by confined impinging jet mixer: poly(lactide-co-glycolide) vs. Poly-ε-caprolactone

This paper is focused on the production and characterization of polymeric nanoparticles obtained by nanoprecipitation. The method consisted of using a confined impinging jet mixer (CIJM), circumventing high-energy equipment. Differences between the use of poly-ε-caprolactone (PCL) and poly(lactide-co-glycolide) (PLGA) as concerns particle mean size, zeta potential, and broad-spectrum antibiotic florfenicol entrapment were investigated. Other analyzed variables were polymer concentration, solvent, and anti-solvent flow rates, and antibiotic initial concentration. To our knowledge, no data were found related to PLGA and PCL nanoparticles comparison using CIJM. Also, florfenicol encapsulation within PCL or PLGA nanoparticles by nanoprecipitation has not been reported yet. The complexity of the nanoprecipitation phenomena has been confirmed, with many relevant variables involved in particles formation. PLGA resulted in smaller and more stable nanoparticles with higher entrapping of florfenicol than PCL.Fil: Turino, Ludmila Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Stella, Barbara. Università di Torino; ItaliaFil: Dosio, Franco. Università di Torino; ItaliaFil: Luna, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Barresi, Antonello A.. Politecnico di Torino; Itali

Fatal Cardiac Arrhythmia and Long-QT Syndrome in a New Form of Congenital Generalized Lipodystrophy with Muscle Rippling (CGL4) Due to PTRF-CAVIN Mutations

We investigated eight families with a novel subtype of congenital generalized lipodystrophy (CGL4) of whom five members had died from sudden cardiac death during their teenage years. ECG studies revealed features of long-QT syndrome, bradycardia, as well as supraventricular and ventricular tachycardias. Further symptoms comprised myopathy with muscle rippling, skeletal as well as smooth-muscle hypertrophy, leading to impaired gastrointestinal motility and hypertrophic pyloric stenosis in some children. Additionally, we found impaired bone formation with osteopenia, osteoporosis, and atlanto-axial instability. Homozygosity mapping located the gene within 2 Mbp on chromosome 17. Prioritization of 74 candidate genes with GeneDistiller for high expression in muscle and adipocytes suggested PTRF-CAVIN (Polymerase I and transcript release factor/Cavin) as the most probable candidate leading to the detection of homozygous mutations (c.160delG, c.362dupT). PTRF-CAVIN is essential for caveolae biogenesis. These cholesterol-rich plasmalemmal vesicles are involved in signal-transduction and vesicular trafficking and reside primarily on adipocytes, myocytes, and osteoblasts. Absence of PTRF-CAVIN did not influence abundance of its binding partner caveolin-1 and caveolin-3. In patient fibroblasts, however, caveolin-1 failed to localize toward the cell surface and electron microscopy revealed reduction of caveolae to less than 3%. Transfection of full-length PTRF-CAVIN reestablished the presence of caveolae. The loss of caveolae was confirmed by Atomic Force Microscopy (AFM) in combination with fluorescent imaging. PTRF-CAVIN deficiency thus presents the phenotypic spectrum caused by a quintessential lack of functional caveolae

TSPO ligand residence time influences human glioblastoma multiforme cell death/life balance

Abstract Ligands addressed to the mitochondrial Translocator Protein (TSPO) have been suggested as cell death/life and steroidogenesis modulators. Thus, TSPO ligands have been proposed as drug candidates in several diseases; nevertheless, a correlation between their binding affinity and in vitro efficacy has not been demonstrated yet, questioning the specificity of the observed effects. Since drug-target residence time is an emerging parameter able to influence drug pharmacological features, herein, the interaction between TSPO and irDE-MPIGA, a covalent TSPO ligand, was investigated in order to explore TSPO control on death/life processes in a standardized glioblastoma cell setting. After 90 min irDE-MPIGA cell treatment, 25 nM ligand concentration saturated irreversibly all TSPO binding sites; after 24 h, TSPO de-novo synthesis occurred and about 40 % TSPO binding sites resulted covalently bound to irDE-MPIGA. During cell culture treatments, several dynamic events were observed: (a) early apoptotic markers appeared, such as mitochondrial membrane potential collapse (at 3 h) and externalization of phosphatidylserine (at 6 h); (b) cell viability was reduced (at 6 h), without cell cycle arrest. After digitonin-permeabilized cell suspension treatment, a modulation of mitochondrial permeability transition pore was evidenced. Similar effects were elicited by the reversible TSPO ligand PIGA only when applied at micromolar dose. Interestingly, after 6 h, irDE-MPIGA cell exposure restored cell survival parameters. These results highlighted the ligand-target residence time and the cellular setting are crucial parameters that should be taken into account to understand the drug binding affinity and efficacy correlation and, above all, to translate efficiently cellular drug responses from bench to bedside

Voluntary Control of Involuntary Utterances: A Treatment Approach for Severe Aphasia

TB

Glioblastoma multiforme: induction of mitochondria-mediated apoptotic pathway by simultaneous pharmacological activation of TSPO (18KDa) and p53.

The resistance of Glioblastoma Multiforme (GBM) to conventional genotoxic modalities suggests to act on intracellular targets that can bypass DNA repair systems and revert the oncogenic blocks commonly found in GBM. One of the main blocks is explicated through the overexpression of the p53 natural inhibitor MDM2 [1]. The oncoprotein MDM2 binds to p53 and mediates its degradation via proteasome [Chromosomes Cancer 1994;11 91-6.]. In the present work, we chose to induce mitochondria-mediated apoptotic pathway by pharmacological activation of the Traslocator Protein (TSPO, 18KDa), which is a crucial component of the mitochondrial multiprotein complex pore [Curr Med Chem. 2003;10:1563-72.], and p53, which can induce formation of mitochondrial membrane pores following oligomerization of pro-apoptotic members of Bcl2 family [Cell Cycle. 2008;7 1949-55]. To activate simultaneously these two targets we used a single molecule, belonging to the new synthetic compound class EB. Such molecules have an indolyl-glyoxyl scaffold decorated with substituents capable of mimicking the interaction site between p53 and MDM2. Furthermore, EB molecules have the structural requirements to interact with TSPO binding site. Competitive binding assays using the TSPO selective [3H]PK11195 radioligand showed that EB bound to TSPO with nanomolar affinity. In isolated mitochondria, EB, following interaction with TSPO, induced prolonged opening of the mitochondrial pore with consequent collapse of mitochondrial membrane potential (Δψm). EB dissociated the complex p53/MDM2 reconstructed in vitro by the use of recombinant proteins and the native p53/MDM2 complex obtained from the GBM U87MG cells. Treatment of U87MG cells with EB effectively induced Δψm dissipation and activation of the mitochondria-mediated apoptotic pathwa

Deep submucosal invasion is not an independent risk factor for lymph node metastasis in T1 colorectal cancer: a meta-analysis

Background & aims: Deep submucosal invasion (DSI) is considered a key risk factor for lymph node metastasis (LNM) and important criterion to recommend surgery in T1 colorectal cancer (CRC). However, metastatic risk for DSI is shown to be low in absence of other histological risk factors. This meta-analysis determines the independent risk of DSI for LNM. Methods: Suitable studies were included to establish LNM-risk for DSI in univariable analysis. To assess DSI as independent risk factor, studies were eligible if 1) risk factors (DSI, poor differentiation (PD), lymphovascular invasion (LVI) and/or high-grade tumor budding (TB)) were simultaneously included in multivariable analysis or 2) LNM-rate of DSI was described in absence of PD, LVI and TB. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. Results: Sixty-seven studies (21,238 patients) were included. Overall LNM-rate was 11.2% and significantly higher for DSI-positive cancers (OR 2.58;95%CI2.10-3.18). Eight studies (3621 patients) were included in multivariable meta-analysis and did not weigh DSI a significant predictor for LNM (OR 1.73;95%CI0.96-3.12). As opposed to a significant association between LNM and PD (OR 2.14;95%CI 1.39-3.28), TB (OR 2.83;95%CI2.06-3.88) and LVI (OR 3.16;95%CI1.88-5.33). Eight studies (1146 patients) analyzed DSI as solitary risk factor: absolute risk of LNM was 2.6% and pooled incidence rate 2.83 (95%CI1.66-4.78). Conclusions: DSI is not a strong independent predictor for LNM and should be reconsidered as a sole indicator for oncologic surgery. The expanding armamentarium for local excision as first-line treatment prompts serious consideration in amenable cases to tailor T1 CRC management