Differentiation state and culture conditions impact neural stem/progenitor cell-derived extracellular vesicle bioactivity.

Extracellular vesicles (EVs) derived from neural progenitor/stem cells (NPSCs) have shown promising efficacy in a variety of preclinical models. However, NPSCs lack critical neuroregenerative functionality such as myelinating capacity. Further, culture conditions used in NPSC EV production lack standardization, limiting reproducibility challenging and potentially potency of the overall approach lack of optimization.

Optimal flip angle for robust practical quantitative NMR measurement using a fixed pulse length.

NMR quantification has been traditionally performed by using internal standards. Although methods using external reference in NMR quantification have been developed, the major obstacles in using external referencing method are the measurement deviations associated with changing sample conditions and the requirement of pulse width calibration for every sample in order to compensate these errors. The calibration process is time consuming and in some cases impossible.

Incidence of diplopia after division and reattachment of the inferior oblique muscle during orbital fracture repair.

Background: Wide surgical access to the orbital floor and medial wall is often impaired by the course of the inferior oblique muscle. There is no current consensus on the optimal surgical approach for exposure, and techniques involving inferior oblique division are generally shunned for concern of possible complications.

Objective: To determine the safety and outcomes of inferior oblique division and reattachment for surgical access to the orbital floor and medial wall during orbital fracture repair.

Advancing RF pulse design using an open-competition format: Report from the 2015 ISMRM challenge.

Purpose: To advance the best solutions to two important RF pulse design problems with an open head-to-head competition.

Methods: Two sub-challenges were formulated in which contestants competed to design the shortest simultaneous multislice (SMS) refocusing pulses and slice-selective parallel transmission (pTx) excitation pulses, subject to realistic hardware and safety constraints. Short refocusing pulses are needed for spin echo SMS imaging at high multiband factors, and short slice-selective pTx pulses are needed for multislice imaging in ultra-high field MRI.

Descemet membrane detachment during cataract surgery: etiology and management.

Purpose Of Review: The review updates the mechanisms, clinical presentations, diagnoses, and managements of Descemet membrane detachment during cataract surgery.

Recent Findings: The advent of new imaging techniques such as anterior segment optical coherence tomography and better comprehension of the clinical and pathological aspects of detachment have improved the diagnosis and treatment of this complication to the extent that the first algorithms and protocols have been proposed.

Summary: Though infrequent, Descemet membrane detachment is a complication of intraocular surgery, including cataract surgery and phacoemulsification.

Correction: A Novel Role for the TIR Domain in Association with Pathogen-Derived Elicitors.

[This corrects the article DOI: 10.1371/journal.pbio.

Quantum-size-controlled photoelectrochemical fabrication of epitaxial InGaN quantum dots.

We demonstrate a new route to the precision fabrication of epitaxial semiconductor nanostructures in the sub-10 nm size regime: quantum-size-controlled photoelectrochemical (QSC-PEC) etching. We show that quantum dots (QDs) can be QSC-PEC-etched from epitaxial InGaN thin films using narrowband laser photoexcitation, and that the QD sizes (and hence bandgaps and photoluminescence wavelengths) are determined by the photoexcitation wavelength. Low-temperature photoluminescence from ensembles of such QDs have peak wavelengths that can be tunably blue shifted by 35 nm (from 440 to 405 nm) and have line widths that narrow by 3 times (from 19 to 6 nm).

Reduction of voxel bleeding in highly accelerated parallel (1) H MRSI by direct control of the spatial response function.

Purpose: To substantially improve spatial localization in magnetic resonance spectroscopic imaging (MRSI) accelerated by parallel imaging. This is important in order to make MRSI more reliable as a tool for clinical applications.

Methods: The sensitivity encoding acceleration technique with spatial overdiscretization is applied for the reconstruction of parallel MRSI.

MRI temporal acceleration techniques.

In recent years, there has been an explosive growth of magnetic resonance imaging (MRI) techniques that allow faster scan speed by exploiting temporal or spatiotemporal redundancy of the images. These techniques improve the performance of dynamic imaging significantly across multiple clinical applications, including cardiac functional examinations, perfusion imaging, blood flow assessment, contrast-enhanced angiography, functional MRI, and interventional imaging, among others. The scan acceleration permits higher spatial resolution, increased temporal resolution, shorter scan duration, or a combination of these benefits.

Hierarchical IDEAL: fast, robust, and multiresolution separation of multiple chemical species from multiple echo times.

We describe a generalized version of hierarchical IDEAL that can flexibly handle arbitrary chemical species at arbitrary echo times. The proposed work is fast and robust, and it has three key features: (1) multiresolution approach, which allows the method to handle images with disjoint regions, makes it less susceptible to local optima, and reduces the ambiguity of the separation; (2) direct phase estimation, which bypasses the phase wrapping issue, and (3) efficient algebraic formulation, which enables fast calculation and insensitivity to spatially varying phase across the image, from sources such as partial echo acquisition, receiver coils, motion, and flow. Representative results at 1.

Preclinical evaluation of potential nilotinib cardiotoxicity.

In vitro, concentrations ≥ 10 μM of nilotinib were needed to induce markers of cytotoxicity, apoptosis, and endoplasmic reticulum stress in both neonatal rat ventricular myocytes, a putative target tissue, and non-target heart fibroblasts, indicating a lack of cardiomyocyte-specific nilotinib toxicity in vitro. In rats, oral nilotinib treatment at 80 mg/kg for 4 weeks induced increased heart weight; however, this was not associated with relevant histopathological changes or effects on heart function. Thus, nilotinib at and above clinically relevant concentrations (4.

Ultrafast imaging: principles, pitfalls, solutions, and applications.

Ultrafast MRI refers to efficient scan techniques that use a high percentage of the scan time for data acquisition. Often, they are used to achieve short scan duration ranging from sub-second to several seconds. Alternatively, they may form basic components of longer scans that may be more robust or have higher image quality.

Discovery of NVP-LDE225, a Potent and Selective Smoothened Antagonist.

The blockade of aberrant hedgehog (Hh) signaling has shown promise for therapeutic intervention in cancer. A cell-based phenotypic high-throughput screen was performed, and the lead structure (1) was identified as an inhibitor of the Hh pathway via antagonism of the Smoothened receptor (Smo). Structure-activity relationship studies led to the discovery of a potent and specific Smoothened antagonist N-(6-((2S,6R)-2,6-dimethylmorpholino)pyridin-3-yl)-2-methyl-4'-(trifluoromethoxy)biphenyl-3-carboxamide (5m, NVP-LDE225), which is currently in clinical development.

Imatinib does not induce cardiotoxicity at clinically relevant concentrations in preclinical studies.

Cytotoxic concentrations of imatinib mesylate (10-50 microM) were required to trigger markers of apoptosis and endoplasmic reticulum stress response in neonatal rat ventricular myocytes and fibroblasts, with no significant differences observed between c-Abl silenced and nonsilenced cells. In mice, oral or intraperitoneal imatinib treatment did not induce cardiovascular pathology or heart failure. In rats, high doses of oral imatinib did result in some cardiac hypertrophy.

Something old, something new: plant innate immunity and autophagy.

Autophagy performs a variety of established functions during plant growth and development. Recently, autophagy has been further implicated in the regulation of programmed cell death induced during the plant innate immune response. In this chapter we describe specific mechanisms through which autophagy may contribute to a successful defense against pathogen invasion.

Autophagy and plant innate immunity: Defense through degradation.

Autophagy is a process of bulk degradation and nutrient sequestration that occurs in all eukaryotes. In plants, autophagy is activated during development, environmental stress, starvation, and senescence. Recent evidence suggests that autophagy is also necessary for the proper regulation of hypersensitive response programmed cell death (HR-PCD) during the plant innate immune response.

Assessment of left ventricular volumes and mass with fast 3D cine steady-state free precession k-t space broad-use linear acquisition speed-up technique (k-t BLAST).

Purpose: To compare left ventricular (LV) volume and mass assessment using two-dimensional (2D) cine steady-state free precession (SSFP) and k-t space broad-use linear acquisition speed-up technique (k-t BLAST) accelerated 3D magnetic resonance imaging (MRI).

Materials And Methods: On a commercially available 1.5T MR scanner, 2D cine SSFP, six- and eight-fold accelerated 3D k-t BLAST were performed to evaluate LV volumes and mass in 17 volunteers.

Determination of peak velocity in stenotic areas: echocardiography versus k-t SENSE accelerated MR Fourier velocity encoding.

The study was approved by the local ethical committees, and informed consent from each participant was obtained. The purpose of the study was to compare accelerated magnetic resonance (MR) Fourier velocity encoding (FVE), MR phase-contrast velocity mapping, and echocardiography with respect to peak velocity determination in vascular or valvular stenoses. FVE data collection was accelerated by using the k-space and time sensitivity encoding, or k-t SENSE, technique.

Accelerated parallel imaging by transform coding data compression with k-t SENSE.

The theory and implementation of the k-t approach (k-t BLAST and k-t SENSE) are reviewed in the context of transform coding. The k-t approach exploits the information redundancy in typical time series of magnetic resonance images that depict anatomy and/or functional parameters. By utilizing this redundancy, it opens up the opportunity for significant acceleration, which in turn allows for scan time reduction, improvements in spatial or temporal resolution, or extended volume coverage for a given acquisition time.

A novel role for the TIR domain in association with pathogen-derived elicitors.

Plant innate immunity is mediated by Resistance (R) proteins, which bear a striking resemblance to animal molecules of similar function. Tobacco N is a TIR-NB-LRR R gene that confers resistance to Tobacco mosaic virus, specifically the p50 helicase domain. An intriguing question is how plant R proteins recognize the presence of pathogen-derived Avirulence (Avr) elicitor proteins.

Minimum-norm reconstruction for sensitivity-encoded magnetic resonance spectroscopic imaging.

In this work we propose minimum-norm reconstruction as a means to enhance the spatial response behavior in parallel spectroscopic MRI. By directly optimizing the shape of the spatial response function (SRF), the new method accounts for coil sensitivity variation across individual voxels and their side lobes. In this fashion, it mitigates the signal contamination and side-lobe aliasing, to which previous techniques are susceptible at low resolution.

k-t BLAST reconstruction from non-Cartesian k-t space sampling.

Current implementations of k-t Broad-use Linear Acqusition Speed-up Technique (BLAST) require the sampling in k-t space to conform to a lattice. To permit the use of k-t BLAST with non-Cartesian sampling, an iterative reconstruction approach is proposed in this work. This method, which is based on the conjugate gradient (CG) method and gridding reconstruction principles, can efficiently handle data that are sampled along non-Cartesian trajectories in k-t space.

Lattice permutation for reducing motion artifacts in radial and spiral dynamic imaging.

Radial and spiral trajectories exhibit favorable characteristics for dynamic imaging. Nevertheless, changes in image contents during acquisition lead to inconsistencies in the k-space data, which are manifested as streaks or spiral artifacts, respectively. This work proposes the concept of lattice permutation to reorder the data segments for artifact suppression.

Accelerating cine phase-contrast flow measurements using k-t BLAST and k-t SENSE.

Conventional phase-contrast velocity mapping in the ascending aorta was combined with k-t BLAST and k-t SENSE. Up to 5.3-fold net acceleration was achieved, enabling single breath-hold acquisitions.