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Hair cells, the mechanosensory receptors of the inner ear, are responsible for hearing and balance. Hair cell death and consequent hearing loss are common results of treatment with ototoxic drugs, including the widely used aminoglycoside antibiotics. Induction of heat shock proteins (HSPs) confers protection against aminoglycoside-induced hair cell death via paracrine signaling that requires extracellular heat shock 70-kDa protein (HSP70). We investigated the mechanisms underlying this non-cell-autonomous protective signaling in the inner ear. In response to heat stress, inner ear tissue releases exosomes that carry HSP70 in addition to canonical exosome markers and other proteins. Isolated exosomes from heat-shocked utricles were sufficient to improve survival of hair cells exposed to the aminoglycoside antibiotic neomycin, whereas inhibition or depletion of exosomes from the extracellular environment abolished the protective effect of heat shock. Hair cell-specific expression of the known HSP70 receptor TLR4 was required for the protective effect of exosomes, and exosomal HSP70 interacted with TLR4 on hair cells. Our results indicate that exosomes are a previously undescribed mechanism of intercellular communication in the inner ear that can mediate nonautonomous hair cell survival. Exosomes may hold potential as nanocarriers for delivery of therapeutics against hearing loss., Introduction Disabling hearing loss affects approximately 6.1% of the global population (1). Most hearing loss is due to death of sensory hair cells of the inner ear. These mechanosensitive receptor [...]

Antisense oligonucleotides (ASOs) targeting pathologic RNAs have shown promising therapeutic corrections for many genetic diseases including myotonic dystrophy (DM1). Thus, ASO strategies for DM1 can abolish the toxic RNA gain-of-function mechanism caused by nucleus-retained mutant DMPK (DM1 protein kinase) transcripts containing CUG expansions (CUGexps). However, systemic use of ASOs for this muscular disease remains challenging due to poor drug distribution to skeletal muscle. To overcome this limitation, we test an arginine-rich Pip6a cell-penetrating peptide and show that Pip6aconjugated morpholino phosphorodiamidate oligomer (PMO) dramatically enhanced ASO delivery into striated muscles of DM1 mice following systemic administration in comparison with unconjugated PMO and other ASO strategies. Thus, low-dose treatment with Pip6a-PMO-CAG targeting pathologic expansions is sufficient to reverse both splicing defects and myotonia in DM1 mice and normalizes the overall disease transcriptome. Moreover, treated DM1 patient-derived muscle cells showed that Pip6a-PMO-CAG specifically targets mutant CUGexp-DMPK transcripts to abrogate the detrimental sequestration of MBNL1 splicing factor by nuclear RNA foci and consequently MBNL1 functional loss, responsible for splicing defects and muscle dysfunction. Our results demonstrate that Pip6a-PMO-CAG induces long- lasting correction with high efficacy of DM1-associated phenotypes at both molecular and functional levels, and strongly support the use of advanced peptide conjugates for systemic corrective therapy in DM1., Introduction Myotonic dystrophy (DM1), one of the most common muscular dystrophies in adults (1), is an RNA-dominant disorder caused by the expression of expanded microsatellite repeats located in the 3' [...]

In this report we summarize the many dark matter searches currently beingpursued through four complementary approaches: direct detection, indirectdetection, collider experiments, and astrophysical probes. The essentialfeatures of broad classes of experiments are described, each with their ownstrengths and weaknesses. The complementarity of the different dark mattersearches is discussed qualitatively and illustrated quantitatively in twosimple theoretical frameworks. Our primary conclusion is that the diversity ofpossible dark matter candidates requires a balanced program drawing from allfour approaches.

The exquisite sensitivity of mitotic cancer cells to ionizing radiation (IR) underlies an important rationale for the widely used fractionated radiation therapy. However, the mechanism for this cell cycle-dependent vulnerability is unknown. Here we show that treatment with IR leads to mitotic chromosome segregation errors in vivo and long-lasting aneuploidy in tumour-derived cell lines. These mitotic errors generate an abundance of micronuclei that predispose chromosomes to subsequent catastrophic pulverization thereby independently amplifying radiation-induced genome damage. Experimentally suppressing whole-chromosome missegregation reduces downstream chromosomal defects and significantly increases the viability of irradiated mitotic cells. Further, orthotopically transplanted human glioblastoma tumours in which chromosome missegregation rates have been reduced are rendered markedly more resistant to IR, exhibiting diminished markers of cell death in response to treatment. This work identifies a novel mitotic pathway for radiation-induced genome damage, which occurs outside of the primary nucleus and augments chromosomal breaks. This relationship between radiation treatment and whole-chromosome missegregation can be exploited to modulate therapeutic response in a clinically relevant manner.

Objective: To examine levator veli palatini muscle composition in patients with nonsyndromic cleft palate and investigate the impact of Veau class. Design: Prospective cohort study. Setting: Tertiary care academic hospital. Patients/Participants: Thirteen patients with nonsyndromic cleft palate were recruited. Interventions: During primary palatoplasty, a sample of levator veli palatini muscle was excised and prepared for histological analysis. Main Outcome Measures: Fat and collagen content were determined utilizing Oil Red and Sirius red stains, respectively, while muscle fiber cross-sectional areas were calculated from H&E-stained samples, with analysis using histomorphometric methods. Immunofluorescent staining of myosin heavy chain isoforms was performed. Results: Patients underwent repair at 10.8 months of age (interquartile range [IQR] 10.2-12.9). Fat content of the levator veli palatini muscle was low in both groups, ranging from 0% to 5.2%. Collagen content ranged from 8.5% to 39.8%; neither fat nor collagen content showed an association with Veau classes. Mean muscle fiber cross-sectional area decreased with increasing Veau class, from 808 µm2 (range 692-995 µm2) in Veau II to 651 µm2 (range 232-750 µm2) in Veau III (P =.02). There was also a nonsignificant decrease in proportion of type I muscle fibers with increasing Veau class (44.3% [range 31.4%-84.4%] in Veau II vs 35.3% [range 17.4%-61.3%] in Veau III). Conclusions: Muscle fiber area in levator veli palatini muscles decreases in Veau III clefts in comparison to Veau II. The impact of these differences in velopharyngeal dysfunction requires further analysis of a larger cohort. [ABSTRACT FROM AUTHOR]

Opportunities exist to reduce nitrous oxide (N2O) emissions from nitrogen (N) fertilizers using enhanced efficiency fertilizers (EEFs) and managing application timing. This study examined (1) application timing (fall/spring) and (2) fertilizer N source on N2O emissions, yield, and N uptake of Canadian hard red spring wheat (Triticum aestivum L.) in Southern Manitoba. Fertilizer N sources included granular urea and four EEF products: (1) polymer‐coated urea (environmentally smart nitrogen [ESN]); (2) urea plus nitrification inhibitor (eNtrench); (3) urea plus urease inhibitor (Limus); and (4) urea plus nitrification and urease inhibitor (SuperU). Nitrification‐inhibited products most consistently reduced N2O emissions while maintaining productivity. Compared to urea alone, urea + eNtrench was most effective in reducing cumulative N2O emissions by 47%–64% at four of six site‐years. SuperU reduced N2O emissions by 37%–57% at three of six site‐years. ESN and urea + Limus did not affect emissions in most years. Wheat yield, protein, and N uptake were unaffected by N source in five of six site‐years. Compared to spring, fall application gave greater N2O emissions by 33%–67% at three of six site‐years due to spring‐thaw emissions. Fall was inferior to spring application in wetter site years with lower yield, protein, and N uptake. Overall, nitrification‐inhibited products—either alone or with a urease inhibitor—are a promising tool to reduce N2O emissions while maintaining wheat productivity in Manitoba. However, given that there were few consistent increases in yield or protein, the additional cost of the inhibitors will be a barrier to adoption. Core Ideas: EEF products with nitrification and nitrification/urease inhibitors consistently reduced N2O emissions.Controlled release urea and urease‐inhibited urea did not reduce N2O emissions.Fall application of urea increased N2O emissions in three site‐years compared to spring application.The nitrification inhibitors applied with urea in fall or spring were effective to reduce N2O emissions.Overall, fall application decreased yield, grain protein, and N uptake in relatively wet years. [ABSTRACT FROM AUTHOR]

This paper develops and applies the concept of accountability styles for analyzing and comparing accountability practices in different countries. This is relevant as there is considerable scholarship on public sector accountability but only very few comparative studies. Extant studies have shown that national styles of accountability are both marked by convergence as well as the resilience of national differences. The concept of accountability style is adopted to describe and interpret how and why accountability practices differ between administrative systems. It does so by analyzing practices of accountability of public sector agencies in four European democracies with different state traditions: the Netherlands, Norway, Switzerland and the UK. These countries vary with regards to state strength (interventionist propensity) and administrative concentration (high or low centralization). The analysis focuses on the accountability of arms' length agencies which lends itself for comparisons across counties. The paper shows that the national political-administrative context crucially shapes practices of accountability and accountability regimes of agencies. The Norwegian accountability style is characterized as 'centralized and convenient'. The UK-style is equally centralized yet not so convenient as it incurs high accountability-process costs on agencies. Switzerland is marked by limited hierarchical accountability. And the Dutch accountability style is comparatively 'broad and informal'. State strength and administrative concentration explain some of the variance while historical legacies explain additional national variations. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Promoting regeneration after segmental nerve injury repair is a challenge, but improving angiogenesis could be beneficial. Macrophages facilitate regeneration after injury by promoting angiogenesis. Our aim in this study was to evaluate the feasibility and effects of transplanting exogenous macrophages to a segmental nerve injury. Methods: Bone marrow–derived cells were harvested from donor mice and differentiated to macrophages (BMDM), then suspended within fibrin hydrogels to facilitate BMDM transplantation. BMDM survival was characterized in vitro. The effect of this BMDM fibrin hydrogel construct at a nerve injury site was assessed using a mouse sciatic nerve gap injury. Mice were equally distributed to "fibrin+Mφ" (fibrin hydrogels containing culture medium and BMDM) or "fibrin" hydrogel control (fibrin hydrogels containing culture medium alone) groups. Flow cytometry (n = 3/group/endpoint) and immunohistochemical analysis (n = 5/group/endpoint) of the nerve gap region were performed at days 3, 5, and 7 after repair. Results: Incorporating macrophage colony‐stimulating factor (M‐CSF) improved BMDM survival and expansion. Transplanted BMDM survived for at least 7 days in a nerve gap (~40% retained at day 3 and ~15% retained at day 7). From transplantation, macrophage quantities within the nerve gap were elevated when comparing fibrin+Mφ with fibrin control (~25% vs. 3% at day 3 and ~14% vs. 6% at day 7). Endothelial cells increased by about fivefold within the nerve gap, and axonal extension into the nerve gap increased almost twofold for fibrin+Mφ compared with fibrin control. Discussion: BMDM suspended within fibrin hydrogels at a nerve gap do not impair regeneration. [ABSTRACT FROM AUTHOR]