Silkworm Coatomers and Their Role in Tube Expansion of Posterior Silkgland

Background: Coat protein complex I (COPI) vesicles, coated by seven coatomer subunits, are mainly responsible for Golgito-ER transport. Silkworm posterior silkgland (PSG), a highly differentiated secretory tissue, secretes fibroin for silk production, but many physiological processes in the PSG cells await further investigation. Methodology/Principal Findings: Here, to investigate the role of silkworm COPI, we cloned six silkworm COPI subunits (a,b,b9, d, e, and f-COP), determined their peak expression in day 2 in fifth-instar PSG, and visualized the localization of COPI, as a coat complex, with cis-Golgi. By dsRNA injection into silkworm larvae, we suppressed the expression of a-, b9- and c-COP, and demonstrated that COPI subunits were required for PSG tube expansion. Knockdown of a-COP disrupted the integrity of Golgi apparatus and led to a narrower glandular lumen of the PSG, suggesting that silkworm COPI is essential for PSG tube expansion. Conclusions/Significance: The initial characterization reveals the essential roles of silkworm COPI in PSG. Although silkworm COPI resembles the previously characterized coatomers in other organisms, some surprising findings require further investigation. Therefore, our results suggest the silkworm as a model for studying intracellular transport, and woul

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Characterisation of CorGlaes (R) Pure 107 fibres for biomedical applications

A degradable ultraphosphate (55 mol % P2O5) quinternary phosphate glass composition has been characterised in terms of its chemical, mechanical and degradation properties both as a bulk material and after drawing into fibres. This glass formulation displayed a large processing window simplifying fibre drawing. The fibres displayed stiffness and strength of 65.5 ± 20.8 GPa and 426±143 MPa. While amorphous discs of the glass displayed a linear dissolution rate of 0.004 mg cm−2 h−1 at 37 °C, in a static solution with a reduction in media pH. Once drawn into fibres, the dissolution process dropped the pH to <2 in distilled water, phosphate buffer saline and corrected-simulated body fluid, displaying an autocatalytic effect with >90 % mass loss in 4 days, about seven times faster than anticipated for this solution rate. Only cell culture media was able to buffer the pH taking over a week for full fibre dissolution, however, still four times faster dissolution rate than as a bulk material. However, at early times the development of a HCA layer was seen indicating potential bioactivity. Thus, although initial analysis indicated potential orthopaedic implant applications, autocatalysis leads to accelerating degradation in vitro

The feasibility and acceptability of a classroom-based physical activity program for children attending specialist schools: a mixed-methods pilot study.

BACKGROUND: Children with disabilities often engage in less than the recommended amount of daily physical activity (PA). Classroom-based PA breaks are a favourable method of promoting PA for children. However, evaluations of these programs in specialist schools are scarce, with even less research into their feasibility and acceptability. This may hinder effective implementation and program scalability. This pilot study investigated the feasibility and acceptability of implementing a classroom-based PA break program in Australian specialist school classrooms, using the Australian Joy of Moving (AJoM) program. METHODS: Forty primary/junior classes and their teachers across five specialist schools implemented the AJoM program for eight weeks as the intervention group within a pilot cluster randomised controlled trial. A mixed-methods design investigated classroom teachers' (N = 22; 6 males, 16 females) perspectives of the feasibility and acceptability of the program after implementation through semi-structured telephone interviews (n = 7 teachers), qualitative survey responses (n = 18 teachers) and quantitative survey items (n = 19 teachers). Qualitative data were analysed using predominantly deductive thematic analysis. Quantitative data were analysed using descriptive statistics. RESULTS: Classroom-based PA breaks may be feasible for getting children with disabilities more active at school. However, considerable variation exists in teachers' perception of the AJoM experience. While several teachers indicate that the program content could be pertinent for their class, common divergences in perceptions of feasibility and acceptability appear to relate to the age and developmental level or needs of the students in the class. CONCLUSIONS: This study provides preliminary evidence for the feasibility and acceptability of implementing classroom-based PA breaks in specialist schools. However, results demonstrate the importance of (1) allowing a high level of flexibility in the design and implementation of programs to meet the varying needs of class groups and (2) providing a large variety of resources to cater to the heterogeneity of the children. TRIAL REGISTRATION: This trial was prospectively registered with the Australian New Zealand Clinical Trials Registry ( ACTRN12619000193178 ) on 11 February 2019