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Reducing the size of lasers to microscale dimensions enables new technologies1 that are specifically tailored for operation in confined spaces ranging from ultra-high-speed microprocessors2 to live brain tissue3. However, reduced cavity sizes increase optical losses and require greater input powers to reach lasing thresholds. Multiphoton-pumped lasers4-7 that have been miniaturized using nanomaterials such as lanthanide-doped upconverting nanoparticles (UCNPs)8 as lasing media require high pump intensities to achieve ultraviolet and visible emission and therefore operate under pulsed excitation schemes. Here, we make use of the recently described energy-looping excitation mechanism in Tm3+-doped UCNPs9 to achieve continuous-wave upconverted lasing action in stand-alone microcavities at excitation fluences as low as 14 kW cm-2. Continuous-wave lasing is uninterrupted, maximizing signal and enabling modulation of optical interactions10. By coupling energy-looping nanoparticles to whispering-gallery modes of polystyrene microspheres, we induce stable lasing for more than 5 h at blue and near-infrared wavelengths simultaneously. These microcavities are excited in the biologically transmissive second near-infrared (NIR-II) window and are small enough to be embedded in organisms, tissues or devices. The ability to produce continuous-wave lasing in microcavities immersed in blood serum highlights practical applications of these microscale lasers for sensing and illumination in complex biological environments.

Functionalization of nanocrystals is essential for their practical application, but synthesis on nanocrystal surfaces is limited by incompatibilities with certain key reagents. The copper-catalyzed azide-alkyne cycloaddition is among the most useful methods for ligating molecules to surfaces, but has been largely useless for semiconductor quantum dots (QDs) because Cu+ ions quickly and irreversibly quench QD fluorescence. To discover nonquenching synthetic conditions for Cu-catalyzed click reactions on QD surfaces, we developed a combinatorial fluorescence assay to screen >2000 reaction conditions to maximize cycloaddition efficiency while minimizing QD quenching. We identify conditions for complete coupling without significant quenching, which are compatible with common QD polymer surfaces and various azide/alkyne pairs. Based on insight from the combinatorial screen and mechanistic studies of Cu coordination and quenching, we find that superstoichiometric concentrations of Cu can promote full coupling if accompanied by ligands that selectively compete with the Cu from the QD surface but allow it to remain catalytically active. Applied to the conjugation of a K+ channel-specific peptidyl toxin to CdSe/ZnS QDs, we synthesize unquenched QD conjugates and image their specific and voltage-dependent affinity for K+ channels in live cells.

We report the fabrication of aqueous multimodal imaging nanocomposites based on superparamagnetic nanoparticles (MNPs) and two different sizes of photoluminescent upconverting nanoparticles (UCNPs). The controlled and simultaneous incorporation of both types of nanoparticles (NPs) was obtained by controlling the solvent composition and the addition rate of the destabilizing solvent. The magnetic properties of the MNPs remained unaltered after their encapsulation into the polymeric beads as shown by the T2 relaxivity measurements. The UCNPs maintain photoluminescent properties even when embedded with the MNPs into the polymer bead. Moreover, the light emitted by the magnetic and upconverting nanobeads (MUCNBs) under NIR excitation (λexc = 980 nm) was clearly observed through different thicknesses of agarose gel or through a mouse skin layer. The comparison with magnetic and luminescent nanobeads based on red-emitting quantum dots (QDs) demonstrated that while the QD-based beads show significant autofluorescence background from the skin, the signal obtained by the MUCNBs allows a decrease in this background. In summary, these results indicate that MUCNBs are good magnetic and optical probes for in vivo multimodal imaging sensors.

Semiconductor quantum dots (QDs) have proven to be superior probes for single-molecule imaging compared to organic or genetically encoded fluorophores, but they are limited by difficulties in protein targeting, their larger size, and on-off blinking. Here, we report compact aqueous CdSe/CdS QDs with significantly improved bioconjugation efficiency and superior single-molecule optical properties. We have synthesized covalent protein labeling ligands (i.e., SNAP tags) that are optimized for nanoparticle use, and QDs functionalized with these ligands label SNAP-tagged proteins ∼10-fold more efficiently than existing SNAP ligands. Single-molecule analysis of these QDs shows 99% of time spent in the fluorescent on-state, ∼4-fold higher quantum efficiency than standard CdSe/ZnS QDs, and 350 million photons detected before photobleaching. Bright signals of these QDs enable us to track the stepping movement of a kinesin motor in vitro, and the improved labeling efficiency enables tracking of single kinesins in live cells.

ObjectivesThe common data elements (CDE) project was developed by the National Institute of Neurological Disorders and Stroke (NINDS) to provide clinical researchers with tools to improve data quality and allow for harmonization of data collected in different research studies. CDEs have been created for several neurological diseases; the aim of this project was to develop CDEs specifically curated for mitochondrial disease (Mito) to enhance clinical research.MethodsNine working groups (WGs), composed of international mitochondrial disease experts, provided recommendations for Mito clinical research. They initially reviewed existing NINDS CDEs and instruments, and developed new data elements or instruments when needed. Recommendations were organized, internally reviewed by the Mito WGs, and posted online for external public comment for a period of eight weeks. The final version was again reviewed by all WGs and the NINDS CDE team prior to posting for public use.ResultsThe NINDS Mito CDEs and supporting documents are publicly available on the NINDS CDE website ( https://commondataelements.ninds.nih.gov/ ), organized into domain categories such as Participant/Subject Characteristics, Assessments, and Examinations.ConclusionWe developed a comprehensive set of CDE recommendations, data definitions, case report forms (CRFs), and guidelines for use in Mito clinical research. The widespread use of CDEs is intended to enhance Mito clinical research endeavors, including natural history studies, clinical trial design, and data sharing. Ongoing international collaboration will facilitate regular review, updates and online publication of Mito CDEs, and support improved consistency of data collection and reporting.

This article presents an innovative narrative inquiry study carried out in a primary school in Aotearoa New Zealand with three young people who provide insights into how they perceive, construct, give meaning to, and make sense of their own emotions. The analysis from this primary research draws on Foucauldian scholarship to examine how the narratives that young people construct about their feelings are shaped by dominant psy-discourses on emotions. We argue that through these discourses, certain voices of authority, knowledge, and ways of seeing are privileged in schools—while others are silenced—in order to label young people as emotionally or mentally "unwell" and in need of expert assistance. In doing so, we suggest that critical interdisciplinary work by health, psychology, counselling, and education professionals in schools can create spaces to explore inter-professional dialogue and reflexivity, as well as to challenge orthodox approaches to young people's emotional lives. [ABSTRACT FROM AUTHOR]

An abnormally expanded GGGGCC repeat in C9ORF72 is the most frequent causal mutation associated with amyotrophic lateral sclerosis (ALS)/frontotemporal lobar degeneration (FTLD). Both gain-of-function (gf) and loss-of-function (lf) mechanisms have been involved in C9ORF72 related ALS/FTLD. The gf mechanism of C9ORF72 has been studied in various animal models but not in C. elegans. In the present study, we described mutant C9ORF72 modeling in C. elegans and report the finding of two suppressor genes. We made transgenes containing 9 or 29 repeats of GGGGCC in C9ORF72, driven by either the hsp-16 promoters or the unc-119 promoter. Transgenic worms were made to carry such transgenes. Phenotypic analysis of those animals revealed that Phsp-16::(G4C2)29::GFP transgenic animals (EAB 135) displayed severe paralysis by the second day of adulthood, followed by lethality, which phenotypes were less severe in Phsp-16::(G4C2)9::GFP transgenic animals (EAB242), and absent in control strains expressing empty vectors. Suppressor genes of this locomotor phenotype were pursued by introducing mutations with ethyl methanesulfonate in EAB135, screening mutant strains that moved faster than EAB135 by a food-ring assay, identifying mutations by whole-genome sequencing and testing the underlying mechanism of the suppressor genes either by employing RNA interference studies or C. elegans genetics. Three mutant strains, EAB164, EAB165 and EAB167, were identified. Eight suppressor genes carrying nonsense/canonical splicing site mutations were confirmed, among which a nonsense mutation of F57A10.2/VAMP was found in all three mutant strains, and a nonsense mutation of acp-4/ACP2 was only found in EAB164. Knock down/out of those two genes in EAB135 animals by feeding RNAi/introducing a known acp-4 null allele phenocopied the suppression of the C9ORF72 variant related movement defect in the mutant strains. Translational conformation in a mammalian system is required, but our worm data suggest that altering acp-4/ACP2 encoding lysosomal acid phosphatase may provide a potential therapeutic method of reducing acp-4/ACP2 levels, as opposed or complementary to directly reducing C9ORF72, to relieve C9ORF72-ALS phenotypes. It also suggests that the C9ORF72-ALS/FTLD may share a pathophysiologic mechanism with vesicle-associated membrane protein-associated protein B, a homolog of F57A10.2/VAMP, which is a proven ALS8 gene.

Parkinson's disease (PD) is a neurodegenerativa disorder associated with loss of striatal dopamine, secondary to degeneration of midbrain dopamine (mDA) neurons in the substantia nigra, rendering cell transplantation a promising therapeutic strategy. To establish human induced pluripotent stem cell-based (hiPSC-based) autologous cell therapy, we report a platform of core techniques for the production of mDA progenitors as a safe and effective therapeutic product. First, by combining metabolism-regulating microRNAs with reprogramming factors, we developed a method to more efficiently generate clinical-grade iPSCs, as evidenced by genomic integrity and unbiased pluripotent potential. Second, we established a 'spotting'-based in vitro differentiation methodology to generate functional and healthy mDA cells in a scalable manner. Third, we developed a chemical method that safely eliminates undifferentiated cells from the final product. Dopaminergic cells thus express high levels of characteristic mDA markers, produce and secrete dopamine, and exhibit electrophysiological features typical of mDA cells. Transplantation of these cells into rodent models of PD robustly restores motor function and reinnervates host brain, while showing no evidence of tumor formation or redistribution of the implanted cells. We propose that this platform is suitable for the successful implementation of human personalized autologous cell therapy for PD., Introduction Parkinson's disease (PD), characterized by both motor and nonmotor system pathology, is a common neurodegenerative disorder affecting about 1% of the population over age 60. Its prevalence presents an [...]

Both nonaffective and affective psychoses are associated with deficits in social functioning across the course of the illness. However, it is not clear how social functioning varies among diagnostic groups as a function of age. The current study examined the relationship between social functioning and age in schizophrenia (SZ), schizoaffective disorder (SZA), and psychotic bipolar disorder (PBD). We found that individuals with PBD had the highest functioning, whereas individuals with SZ had the poorest. The functioning of individuals with SZA fell in between those of other groups. We also found that older ages were associated with poorer functioning. Although there was not a significant diagnostic group by age interaction, visual inspection of our data suggests a subtly steeper trajectory of decline in PBD. Overall, these results indicate that early interventions targeting social functioning may benefit individuals with either non-affective or affective psychoses to slow a projected decline.