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ObjectiveTo compare and contrast the perceived care needs of children with life-limiting conditions (CLLC) from the perspectives of the children, parents and healthcare providers.DesignA qualitative case study method using semistructured interviews was employed with a within-case and across-case analysis. Themes and subthemes emerging from the cases were compared and contrasted in the across-case analysis to explore the similarities and variations in participant perceptions.Setting/participantsThe setting was the paediatric departments of five regional hospitals in Hong Kong. Twenty-five sets of informants (CLLC–parent–healthcare provider) were recruited, with 65 individual interviews conducted.ResultsA total of 3784 units of analysis were identified, resulting in three themes with subthemes. ‘Living with the disease’ (55.8%) occupied the largest proportion, followed by ‘information and understanding about the disease’ (27.4%), and ‘care support and palliative care’ (16.8%). Healthcare provider support mainly focused on physical concerns. Family and social support were present, but carer stress created tension between couples. Doctors were the primary source of medical information, but the parents had to seek further information via the internet and support from patient groups. There was a perceived need for better coordination and collaboration of care. The palliative care approach coordinated by nurses was seen as helpful in addressing the care needs of the CLLC.ConclusionsThis original study identified the importance of palliative care with active engagement of parents which can address the service gap for CLLC.

Mechanical feedback is one of the most common difficulties encountered when fitting hearing aids for toddlers and young children. We described the use of 3D printing to tailor a protective cap for a toddler with bilateral microtia/canal atresia to facilitate bone-anchoring hearing aid use.

In this study, Rajakulendran et al. investigated the role of Wnt/βcatenin signaling in GBM stem cell renewal and fate decisions. They identify new contexts for Wnt modulation for targeting stem cell differentiation and self-renewal in GBM heterogeneity.

Human glioblastomas harbour a subpopulation of glioblastoma stem cells that drive tumorigenesis. However, the origin of intratumoural functional heterogeneity between glioblastoma cells remains poorly understood. Here we study the clonal evolution of barcoded glioblastoma cells in an unbiased way following serial xenotransplantation to define their individual fate behaviours. Independent of an evolving mutational signature, we show that the growth of glioblastoma clones in vivo is consistent with a remarkably neutral process involving a conserved proliferative hierarchy rooted in glioblastoma stem cells. In this model, slow-cycling stem-like cells give rise to a more rapidly cycling progenitor population with extensive self-maintenance capacity, which in turn generates non-proliferative cells. We also identify rare ‘outlier’ clones that deviate from these dynamics, and further show that chemotherapy facilitates the expansion of pre-existing drug-resistant glioblastoma stem cells. Finally, we show that functionally distinct glioblastoma stem cells can be separately targeted using epigenetic compounds, suggesting new avenues for glioblastoma-targeted therapy.

IMPORTANCE Mutations in the GNAL gene have recently been shown to cause primary torsion dystonia. The GNAL-encoded protein (Gαolf) is important for dopamine D1 receptor function and odorant signal transduction. We sequenced all 12 exons of GNAL in 461 patients from Germany, Serbia, and Japan, including 318 patients with dystonia (190 with cervical dystonia), 51 with hyposmia and Parkinson disease, and 92 with tardive dyskinesia or acute dystonic reactions. OBSERVATIONS We identified the following two novel heterozygous putative mutations in GNAL: p.Gly213Ser in a German patient and p.Ala353Thr in a Japanese patient. These variants were predicted to be pathogenic in silico, were absent in ethnically matched control individuals, and impaired Gαolf coupling to D1 receptors in a bioluminescence energy transfer (BRET) assay. Two additional variants appeared to be benign because they behaved like wild-type samples in the BRET assay (p.Ala311Thr) or were detected in ethnically matched controls (p.Thr92Ala). Both patients with likely pathogenic mutations had craniocervical dystonia with onset in the fifth decade of life. No pathogenic mutations were detected in the patients with hyposmia and Parkinson disease, tardive dyskinesias, or acute dystonic reactions. CONCLUSIONS AND RELEVANCE Mutations in GNAL can cause craniocervical dystonia in different ethnicities. The BRET assay may be a useful tool to support the pathogenicity of identified variants in the GNAL gene.

Maltase/glucoamylase from the rat intestinal brush-border membrane was solubilized by homogenization of the intestinal mucosa in buffer containing 0.5% Triton X-100. After removal of the detergent with butan-1-ol, the enzyme was purified by chromatography on Sepharose 4B and DEAE-cellulose. The final specific activity was 70.3 units/mg of protein in six preparations, comparing favourably with the specific activity of 65.0 units/mg of protein of a pure papain-solubilized maltase/glucoamylase previously isolated and characterized by us [Flanagan & Forstner (1978) Biochem. J.173, 553–563]. The two enzymes were compared. Both migrated as single bands with the same mobility on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, were eluted at the same volume from Sepharose 4B, and had the same sedimentation pattern in mannitol gradients. The amino acid composition was similar; content of total apolar residues differed by 1.0mol%. Antibodies prepared against either enzyme gave identical precipitin lines with each. Neither enzyme bound tritiated Triton X-100. The only difference noted was the tendency of the detergent-solubilized enzyme to aggregate on storage, whereas the papain-solubilized enzyme remained unchanged. Both enzymes had two N-termini, glycine and arginine. When the two enzymes were dissociated by boiling in sodium dodecyl sulphate, each exhibited the same five species on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Single N-termini were found in the two smaller species, 1 (glycine) and 2 (arginine), whereas larger species (3–5) had both N-terminal amino acids. Both the Triton- and papain-solubilized enzymes appear to be oligomers of species 1 and 2, indicating that the native enzyme contains two subunit types. Aggregation in aqueous solutions does not depend on a proteolytically susceptible peptide fragment at the N-terminus of either subunit.

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Medulloblastoma (MB) is a neoplasm linked to dysregulated cerebellar development. Previously, we demonstrated that the Sonic Hedgehog (SHH) subgroup grows hierarchically, with Sox2+cells at the apex of tumor progression and relapse. To test whether this mechanism is rooted in a normal developmental process, we studied the role of Sox2 in cerebellar development. We find that the external germinal layer (EGL) is derived from embryonic Sox2+precursors and that the EGL maintains a rare fraction of Sox2+cells during the first postnatal week. Through lineage tracing and single-cell analysis, we demonstrate that these Sox2+cells are within the Atoh1+lineage, contribute extensively to adult granule neurons, and resemble Sox2+tumor cells. Critically, constitutive activation of the SHH pathway leads to their aberrant persistence in the EGL and rapid tumor onset. We propose that failure to eliminate this rare but potent developmental population is the tumor initiation mechanism in SHH-subgroup MB.

Glioblastomas exhibit a hierarchical cellular organization, suggesting that they are driven by neoplastic stem cells that retain partial yet abnormal differentiation potential. Here, we show that a large subset of patient-derived glioblastoma stem cells (GSCs) express high levels of Achaete-scute homolog 1 (ASCL1), a proneural transcription factor involved in normal neurogenesis. ASCL1hiGSCs exhibit a latent capacity for terminal neuronal differentiation in response to inhibition of Notch signaling, whereas ASCL1loGSCs do not. Increasing ASCL1 levels in ASCL1loGSCs restores neuronal lineage potential, promotes terminal differentiation, and attenuates tumorigenicity. ASCL1 mediates these effects by functioning as a pioneer factor at closed chromatin, opening new sites to activate a neurogenic gene expression program. Directing GSCs toward terminal differentiation may provide therapeutic applications for a subset of GBM patients and strongly supports efforts to restore differentiation potential in GBM and other cancers.