Controlled degradation of polycaprolactone-based micropillar arrays.

Herein we demonstrate the fabrication of arrays of micropillars, achieved through the combination of direct laser writing and nanoimprint lithography. By combining two diacrylate monomers, polycaprolactone dimethacrylate (PCLDMA) and 1,6-hexanediol diacrylate (HDDA), two copolymer formulations that, owing to the varying ratios of the hydrolysable ester functionalities present in the polycaprolactone moiety, can be degraded in the presence of base in a controllable manner. As such, the degradation of the micropillars can be tuned over several days as a function of PCLDMA concentration within the copolymer formulations, and the topography greatly varied over a short space of time, as visualised using scanning electron microscopy and atomic force microscopy. Crosslinked neat HDDA was used as a control material, demonstrating that the presence of the PCL was responsible for the ability of the microstructures to degrade in the controlled manner. In addition, the mass loss of the crosslinked materials was minimal, demonstrating the degradation of microstructured surfaces without loss of bulk properties was possible. Moreover, the compatibility of these crosslinked materials with mammalian cells was explored. The influence of both indirect and direct contact of the materials with A549 cells was assessed by profiling indices reflective of cytotoxicity such as morphology, adhesion, metabolic activity, oxidative balance, and release of injury markers. No significant changes in the aforementioned profile were observed in the cells cultured under these conditions for up to 72 h, with the cell-material interaction suggesting these materials may have potential in microfabrication contexts towards biomedical application purposes.

Late Diagnosis of Hirschsprung's Disease: Definition and Implication on Core Outcomes.

INTRODUCTION: Late diagnosis of Hirschsprung's disease (LDHD) may carry a poor prognosis. Its definition remains unclear and its implication on HD-related core outcomes has not been fully reported. METHODS: A single-center 20-year series was reviewed to include HD with follow-up of 1 year or more post pull-through (PT) and aged 5 years or older. We investigated six core outcomes derived from NETS1HD study by comparing the groups dichotomized by four time points using age at diagnosis (44-week gestation, 6 months, 1 year, and 3 years). Following establishment of definition of LDHD, the outcomes and complications were compared with timely diagnosis of HD (TDHD). RESULTS: Forty-nine out of eighty-six HD were included. The definition of LDHD was found to be HD diagnosed at 1 year of age or later because 3/6 core outcomes were significantly worse than TDHD. Nine patients (18%) had LDHD-median age at diagnosis 42 months (12-89) and PT performed at 57 months (12-103), mostly Soave (73%); a covering stoma was performed in 7/9, significantly higher than TDHD in 10/40 (p = 0.001). LDHD was associated with increased unplanned surgery (78% vs. 30%, p = 0.019), fecal incontinence (100% vs. 62%, p = 0.01), and permanent stoma (33% vs. 5%, p = 0.037). Major complications (56% vs. 20%, p = 0.043) and redo PT (33% vs. 5%, p = 0.037) were also higher in LDHD. CONCLUSION: LDHD could be defined as HD diagnosis at or over 1 year of age. LDHD was associated with more preoperative stoma, major postoperative complications, unplanned reoperation, and worse HD-related core outcomes.

The UCD nanosafety workshop (03 December 2018): towards developing a consensus on safe handling of nanomaterials within the Irish university labs and beyond - a report.

Careful handling of the nanomaterials (NMs) in research labs is crucial to ensure a safe working environment. As the largest university in Ireland, University College Dublin (UCD) has invested significant resources to update researchers working with NMs. Due to sizes often <100 nm, the NMs including nanoparticles, harbor unprecedented materialistic properties, for example, enhanced reactivity, conductivity, fluorescence, etc. which albeit conferring the NMs an edge over bulk materials regarding the applied aspects; depending on the dose, also render them to be toxic. Thus, a set of regulatory guidelines have emerged regarding safe handling of the NMs within occupational set-ups. Unfortunately, the current regulations based on the toxic chemicals and carcinogens are often confusing, lack clarity, and difficult to apply for the NMs. As a research-intensive university, a diverse range of research activities occur within the UCD labs, and it is difficult, at times impossible, for the UCD Safety, Insurance, Operational Risk & Compliance (SIRC) office to develop a set of common guidelines and cater throughout all its labs conducting research with the NMs. Hence, a necessity for dialog and exchange of ideas was felt across the UCD which encouraged the researchers including early stage researchers (e.g. PhDs, Postdocs) from multiple schools to participate in a workshop held on the 03 December 2018. The workshop tried to follow a pragmatic approach, where apart from discussing both the in vitro and in vivo scenarios, practical cases simulating situations faced frequently in the labs were discussed. This report summarizes the findings made during the workshop by this emerging critical mass in UCD.

Percutaneous endoscopic colostomy of the left colon: a new technique for management of intractable constipation in children.

BACKGROUND: The antegrade colonic enema is accepted as effective for management of intractable constipation in children when conventional bowel management has failed. This study describes experience with a new, minimally invasive technique, the distal antegrade colonic enema, which involves percutaneous endoscopic colostomy of the left colon. METHODS: Fifteen children with refractory constipation and soiling who had radiographic evidence of megarectum and/or distal colonic delay were selected for the procedure. The junction of the descending and the sigmoid colon was identified colonoscopically, and the percutaneous endoscopic colostomy tube, through which antegrade distal colonic enema are administered, was inserted. RESULTS: Fourteen children underwent distal percutaneous endoscopic colostomy insertion. The median time required for the procedure was 30 minutes (20-50 minutes). Excluding one child (technical difficulties with percutaneous endoscopic colostomy placement), median post-procedural hospital stay was 4 days (2-27 days). Thirteen children were no longer soiling, and improvement in quality of life was reported at 2 months' follow-up. At 6 months' follow-up, 90% of children were clean during intervals between enemas. All children evaluated at 12 months' follow-up remained clean. Median duration of follow-up was 12.5 months (2-51 months). CONCLUSIONS: The distal percutaneous endoscopic colostomy is a simple alternative to established methods for delivery of antegrade enemas. It is less invasive and on reversal leaves only minor scarring.