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Consuming an unbalanced diet and being overweight represent a global health problem in young people and adults of both sexes, and may lead to metabolic syndrome. The diet-induced obesity (DIO) model in the C57BL/6J mouse substrain that mimics the gradual weight gain in humans consuming a "Western-type" (WD) diet is of great interest. This study aims to characterize this animal model, using high-frequency ultrasound imaging (HFUS) as a complementary tool to longitudinally monitor changes in the liver, heart and kidney. Long-term WD feeding increased mice body weight (BW), liver/BW ratio and body condition score (BCS), transaminases, glucose and insulin, and caused dyslipidemia and insulin resistance. Echocardiography revealed subtle cardiac remodeling in WD-fed mice, highlighting a significant age–diet interaction for some left ventricular morphofunctional parameters. Qualitative and parametric HFUS analyses of the liver in WD-fed mice showed a progressive increase in echogenicity and echotexture heterogeneity, and equal or higher brightness of the renal cortex. Furthermore, renal circulation was impaired in WD-fed female mice. The ultrasound and histopathological findings were concordant. Overall, HFUS can improve the translational value of preclinical DIO models through an integrated approach with conventional methods, enabling a comprehensive identification of early stages of diseases in vivo and non-invasively, according to the 3Rs. [ABSTRACT FROM AUTHOR]

Glioblastoma (GB) is a highly malignant primary brain tumor with limited treatment options and poor prognosis. Despite current treatment approaches, including surgical resection, radiation therapy, and chemotherapy with temozolomide (TMZ), GB remains mostly incurable due to its invasive growth pattern, limited drug penetration beyond the blood-brain barrier (BBB), and resistance to conventional therapies. One of the main challenges in GB treatment is effectively eliminating infiltrating cancer cells that remain in the brain parenchyma after primary tumor resection. We've reviewed the most recent challenges and surveyed the potential strategies aimed at enhancing local treatment outcomes. [ABSTRACT FROM AUTHOR]

Objective The CACNA1A gene encodes the pore-forming subunit of neuronal CaV2.1 Ca2+ channels. In patients, the S218L CACNA1A mutation causes a dramatic hemiplegic migraine syndrome that is associated with ataxia, seizures, and severe, sometimes fatal, brain edema often triggered by only a mild head trauma. Methods We introduced the S218L mutation into the mouse Cacna1a gene and studied the mechanisms for the S218L syndrome by analyzing the phenotypic, molecular, and electrophysiological consequences. Results Cacna1aS218L mice faithfully mimic the associated clinical features of the human S218L syndrome. S218L neurons exhibit a gene dosage-dependent negative shift in voltage dependence of CaV2.1 channel activation, resulting in enhanced neurotransmitter release at the neuromuscular junction. Cacna1aS218L mice also display an exquisite sensitivity to cortical spreading depression (CSD), with a vastly reduced triggering threshold, an increased propagation velocity, and frequently multiple CSD events after a single stimulus. In contrast, mice bearing the R192Q CACNA1A mutation, which in humans causes a milder form of hemiplegic migraine, typically exhibit only a single CSD event after one triggering stimulus. Interpretation The particularly low CSD threshold and the strong tendency to respond with multiple CSD events make the S218L cortex highly vulnerable to weak stimuli and may provide a mechanistic basis for the dramatic phenotype seen in S218L mice and patients. Thus, the S218L mouse model may prove a valuable tool to further elucidate mechanisms underlying migraine, seizures, ataxia, and trauma-triggered cerebral edema. ANN NEUROL 2010;67:85-98 [ABSTRACT FROM AUTHOR]

Previously, we demonstrated the racemic form of the valproate (VPA) analogue, 2-n-pentyl-4-pentynoic acid ([±]pentyl-4-yn-VPA), to be neuritogenic in vitro and to enhance cognition in vivo. To determine the enantioselectivity of these effects, the racemate and purified enantiomers of [±]pentyl-4-yn-VPA (84 mg/kg, i.p.) were administered to rodents 20 min prior to multi-session water maze training. The racemate and R-enantiomer significantly reduced escape latencies during water maze learning and enhanced its recall in a probe trial 3 days later. In contrast, S-pentyl-4-yn-VPA did not influence these behavioural parameters. The enantiomer-specific effects of [±]pentyl-4-yn-VPA were further discriminated in vitro using neuro 2A neuroblastoma and C6 glioma cell lines. In neuro 2A, the S-enantiomer induced profound neurite outgrowth at concentrations up to 0.5 m m, with the R-enantiomer and racemate being less neuritogenic. Immunoblot analysis of cyclin D3 expression in C6 glioma indicated the racemate and S-pentyl-4-yn-VPA to induce dose-dependent up-regulation of this protein, similar to that associated with G1-phase cell cycle arrest mediated by VPA, whereas R-pentyl-4-yn-VPA was without effect. These results indicate that the cognition-enhancing effects of pentyl-4-yn-VPA are due to the actions of the R-enantiomer, and that cyclin D3 up-regulation and associated anti-proliferative and pro-differentiative actions are predominantly associated with the S-enantiomer. [ABSTRACT FROM AUTHOR]

Abstract: Nanoparticles have an enormous potential for the development of applications in biomedicine such as gene or drug delivery. We developed and characterized NH2 functionalized CdSe/ZnS quantum dot (QD)-doped SiO2 nanoparticles (NPs) with both imaging and gene carrier capabilities. We show that QD-doped SiO2 NPs are internalized by primary cortical neural cells without inducing cell death in vitro and in vivo. Moreover, the ability to bind, transport and release DNA into the cell allows GFP-plasmid transfection of NIH-3T3 and human neuroblastoma SH-SY5Y cell lines. QD-doped SiO2 NPs properties make them a valuable tool for future nanomedicine application. [Copyright &y& Elsevier]

Superparamagnetic iron oxide nanoparticles (SPIONs) have received increasing interest as contrast media in biomedical imaging and innovative therapeutic tools, in particular for loco-regional ablative treatments and drug delivery. The future of therapeutic applications would strongly benefit from improving the capability of the nanostructured constructs to reach the selected target, in particular beyond the intravascular space. Besides the decoration of SPIONs surface with ad hoc bioactive molecules, external magnetic fields are in principle able to remotely influence SPIONs' physiological biodistribution and concentrate them to a specific anatomical region or portion of a tissue. The reduction of SPIONs administered to the body and the need for defining the effective SPIONs local concentration suggest that PET/CT may be a method to quantitatively detect the nanoparticles accumulation in vivo at low concentration and assess their tridimensional distribution in response to an external magnetic field and in relation to the local anatomy highlighted by CT imaging. Here, we report on the possibility to assess the spatial distribution of magnetically-driven radiolabelled SPIONs in a peripheral tissue (mouse thigh) with microPET/CT imaging. To this aim we labelled SPIONs using 18 F-2-fluoro-2-deoxyglucose as a synthon, by chemoselective oxime formation between its open-chain tautomer and nanoparticle amino-groups, and employed microPET/CT imaging to measure the radiolabelled construct biodistribution in a small animal model, following intravenous administration, with and without the application of a permanent magnet onto the skin. The in vivo and ex vivo results showed that micro-PET/CT was able to demonstrate the localizing action of the magnet on SPIONs and provide information, in a multimodal 3D data set, about SPIONs biodistribution taking into account the local anatomy. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

Ultrasound of 2 MHz frequency and 1.2 W/cm(2) acoustic intensity was applied to examine the effect of sonication on recombinant tissue-type plasminogen activator (rt-PA)-induced thrombolysis as well as on the distribution of plasminogen and t-PA within whole blood clots in vitro. Thrombolysis was evaluated quantitatively by measuring clot weight reduction and the level of fibrin degradation product D-dimer (FDP-DD) in the supernatant. Weight reduction in the group of clots treated both with ultrasound and rt-PA was 35.2% +/-6.9% which is significantly higher (p<0.0001) than in the group of clots treated with rt-PA only (19.9% +/-4.3%). FDP-DD level in the supernatants of the group treated with ultrasound and rt-PA increased sevenfold compared to the group treated with rt-PA alone, (14895 +/-2513 ng/ml vs. 2364 +/-725 ng/ml). Localization of fibrinolytic components within the clots was accomplished by using gel-entrapping technique and immunohistochemistry. Spatial distributions of t-PA and plasminogen showed clearly that ultrasound promoted the penetration of rt-PA into thrombi significantly (p<0.0001), and broadened the zone of lysis from 8.9 +/-2.6 microm to 21.2 +/-7.2 microm. We speculate that ultrasound enhances thrombolysis by affecting the distribution of rt-PA within the clot.