TGF-β signaling links E-cadherin loss to suppression of nucleotide excision repair.

E-cadherin is a cell adhesion molecule best known for its function in suppressing tumor progression and metastasis. Here we show that E-cadherin promotes nucleotide excision repair through positively regulating the expression of xeroderma pigmentosum complementation group C (XPC) and DNA damage-binding protein 1 (DDB1). Loss of E-cadherin activates the E2F4 and p130/107 transcription repressor complexes to suppress the transcription of both XPC and DDB1 through activating the transforming growth factor-β (TGF-β) pathway. Adding XPC or DDB1, or inhibiting the TGF-β pathway, increases the repair of ultraviolet (UV)-induced DNA damage in E-cadherin-inhibited cells. In the mouse skin and skin tumors, UVB radiation downregulates E-cadherin. In sun-associated premalignant and malignant skin neoplasia, E-cadherin is downregulated in association with reduced XPC and DDB1 levels. These findings demonstrate a crucial role of E-cadherin in efficient DNA repair of UV-induced DNA damage, identify a new link between epithelial adhesion and DNA repair and suggest a mechanistic link of early E-cadherin loss in tumor initiation

TYPES OF SUTURING AND THEIR CLINICAL OUTCOME IN OPERATED PATIENTS IN A RURAL TERTIARY CARE SETUP

Introduction: The present study was aimed at different modalities of abdominal skin suturing techniques and their outcome in various abdominal skin incisions. Material and methods: All the patients above the age of 18 years irrespective of gender who were undergoing abdominal surgeries and getting sutured by either Simple, mattress, subcuticular or tension sutures were included in the study. The demography, diagnosis, type of wound & suture and its outcome was followed till day 14. Results: A total of 120 randomly selected cases with different abdominal incisions and different suturing techniques associated with co-morbid factors were selected. Majority of cases i.e, 40 (33.3%) belonged to inguinal hernia, followed by appendicitis, intestinal perforation, intestinal obstruction. Age of 61 to 70 was the most common age group. Most of the cases had clean wound (59) followed by clean contaminated (27) and contaminated wounds (28). The types of sutures observed were simple, mattress, subcuticular and tension, which were done in 30, 24, 30 and 31 patients respectively. Among these the least complications were seen with subcuticular followed by simple type of sutures. The groups of the types of suture used were not comparable due to difference in the type of wound and disease in the patients. Conclusion: Although every type of suture has its own advantages, disadvantage, indications and contraindications, simple and subcuticular sutures have better outcome as compared to other forms of suture. Key words: Abdominal incisions, Clinical outcomes, Suturing techniques

Optimising ply orientation in structural laminated bamboo

Currently, only two forms of laminated bamboo are commercially available as structural materials: unidirectional beams and boards, and cross-laminated boards. As a natural quasi-unidirectional composite, the lamination of bamboo into plies with specific orientations would allow the design and manufacture of a family of multi-axial composite laminates with unique properties. In this study, we test the tensile mechanical properties of single- and two-ply laminated bamboo at various off-axis loading angles and laminate configurations. The data is then compared to micro-mechanical models for predicting modulus and strength of composite laminates. On the basis of our analyses, we believe there is significant scope to extend the current range of laminated bamboo products to include angle-ply laminates. Moreover, we demonstrate that composite laminate theory is applicable to this natural composite and may be used for design of products and structures

The strength of plants: theory and experimental methods to measure the mechanical properties of stems

From the stems of agricultural crops to the structural trunks of trees, studying the mechanical behaviour of plant stems is critical for both commerce and science. Plant scientists are also increasingly relying on mechanical test data for plant phenotyping. Yet there are neither standardized methods nor systematic reviews of current methods for the testing of herbaceous stems. We discuss the architecture of plant stems and highlight important micro- and macrostructural parameters that need to be controlled and accounted for when designing test methodologies, or that need to be understood in order to explain observed mechanical behaviour. Then, we critically evaluate various methods to test structural properties of stems, including flexural bending (two-, three-, and four-point bending) and axial loading (tensile, compressive, and buckling) tests. Recommendations are made on best practices. This review is relevant to fundamental studies exploring plant biomechanics, mechanical phenotyping of plants, and the determinants of mechanical properties in cell walls, as well as to application-focused studies, such as in agro-breeding and forest management projects, aiming to understand deformation processes of stem structures. The methods explored here can also be extended to other elongated, rod-shaped organs (e.g. petioles, midribs, and even roots).This work is part of a project funded by the Leverhulme Trust (Project title: ‘Natural material innovation’). The project forms a collaboration with the Department of Applied Mathematics and Theoretical Physics, Department of Biochemistry, Department of Chemistry, and Department of Plant Sciences at the University of Cambridge

Thermal conductivity of engineered bamboo composites

Here we characterise the thermal properties of engineered bamboo panels produced in Canada, China, and Colombia. Specimens are processed from either Moso or Guadua bamboo into multi-layered panels for use as cladding, flooring or walling. We utilise the transient plane source method to measure their thermal properties and confirm a linear relationship between density and thermal conductivity. Furthermore, we predict the thermal conductivity of a three-phase composite material, as these engineered bamboo products can be described, using micromechanical analysis. This provides important insights on density-thermal conductivity relations in bamboo, and for the first time, enables us to determine the fundamental thermal properties of the bamboo cell wall. Moreover, the density-conductivity relations in bamboo and engineered bamboo products are compared to wood and other engineered wood products. We find that bamboo composites present specific characteristics, for example lower conductivities – particularly at high density – than equivalent timber products. These characteristics are potentially of great interest for low-energy building design. This manuscript fills a gap in existing knowledge on the thermal transport properties of engineered bamboo products, which is critical for both material development and building design.DUS and MCDB thank Mr Robert Cornell (University of Cambridge) for training on thermal conductivity measurement. Special thanks go to Prof Greg Smith and Dr Kate Semple at the University of British Columbia (Department of Wood Science), working on processing of structural bamboo products. This research has been funded by the EPSRC (Grant EP/K023403/1), a Leverhulme Trust Programme Grant, and the Newton Trust.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10853-015-9610-

Spider silk inspired damping fibres drawn from a supramolecular hydrogel composite at room temperature - A step closer to sustainable fibre technology

We report the aqueous self-assembly of hierarchical supramolecular polymer-colloidal hydrogels consisting of functionalized polymer-grafted silica nanoparticles, a hydroxyethyl cellulose derivative and cucurbit[8]uril. The resulting material (98 wt% water) can be drawn into uniform (6 μm) ‘supramolecular fibres’ at room temperature. They exhibited better tensile strength and superior stiffness to natural fibres such as viscose, protein-based silks, and human and animal hair, while cyclic loading tests illustrated their remarkable damping capacity (60–70%). These supramolecular hydrogels represent a new class of hybrid supramolecular composites, opening a window into fibre technology through low-energy manufacturing from a broad range of sustainable materials.Leverhulm

Thermal relaxation of laminated bamboo for folded shells

Laminated bamboo is emerging as a novel material in design and construction. As a natural fibre composite, it has unique mechanical properties that allow for innovations that are not possible in other materials. Here, we discuss one new application of those properties: the development of a novel bending technique using high temperature, and we explore its implications for design. We have explored the fundamental properties of laminated bamboo and its thermal relaxation asit passes the glass transition temperatures of its constituent polymers.By mechanically thinning engineered bamboo material, score lines allow precise, controlled and localised heating that promotes limited but essential elasto-plastic behaviour. Concentrated heating above the glass transition temperature induces property evolution and structural morphology changes, which results in thermal relaxation with minimal recovery and full set upon cooling.This original technology is then deployed in the design and construction of a folded plate helical shell composed of thin laminated bamboo sheets.The presented work is supported by a Leverhulme Trust Programme Grant, and EPSRC Grant EP/K023403/1

A case of chronic progressive Lyme encephalitis as a manifestation of late Lyme neuroborreliosis

A 54-year-old female living in Europe presented with gait ataxia, dizziness, and bilateral hearing loss. Magnetic resonance imaging (MRI) revealed non-specific white matter changes. The patient's condition gradually deteriorated over two years without diagnosis. The patient continued to decline cognitively and neurologically with worsening ataxia and upper motor neuron signs. Repeat MRI showed worsening white matter changes. Lumbar puncture, not previously done, showed positive Lyme testing. Treatment with intravenous ceftriaxone resulted in marked neurological improvement. Four years after symptom, the patient has short-term memory deficits and chronic fatigue, but is otherwise neurologically, cognitively, and functionally intact. Follow up MRI findings remain largely unchanged. Because cases of intraparenchymal or encephalopathic neuroborreliosis in America are lacking, so are treatment options. We present a rare case and discuss our experience with antibiotic treatment. This case lends evidence to define optimal treatment of this disease, imperative for hastening neurological recovery

Relationship of structure and stiffness in laminated bamboo composites

Laminated bamboo in structural applications has the potential to change the way buildings are constructed. The fibrous microstructure of bamboo can be modelled as a fibre-reinforced composite. This study compares the results of a fibre volume fraction analysis with previous experimental beam bending results. The link between fibre volume fraction and bending stiffness shows that differences previously attributed to preservation treatment in fact arise due to strip thickness. Composite theory provides a basis for the development of future guidance for laminated bamboo, as validated here. Fibre volume fraction analysis is an effective method for non-destructive evaluation of bamboo beam stiffness

Cell geometry across the ring structure of Sitka spruce.

For wood to be used to its full potential as an engineering material, it is necessary to quantify links between its cell geometry and the properties it exhibits at bulk scale. Doing so will make it possible to predict timber properties crucial to engineering, such as mechanical strength and stiffness, and the resistance to fluid flow, and to inform strategies to improve those properties as required, as well as to measure the effects of interventions such as genetic manipulation and chemical modification. Strength, stiffness and permeability of timber all derive from the geometry of its cells, and yet current practice is to predict them based on properties, such as bulk density, that do not directly describe the cell structure. This work explores links between micro-computed tomography data for structural-size pieces of wood, which show the variation of porosity across the wood's ring structure, and high-resolution tomography showing the geometry of the cells, from which we measure cell length, lumen area, porosity, cell wall thickness and the number density of cells. High-resolution scans, while informative, are time-consuming and expensive to run on a large number of samples at the scale of building components. By scanning the same volume of timber at both low and high resolutions (high-resolution scans over a near-continuous volume of timber of approx. 20 mm3 at 15 μm3 per voxel), we are able to demonstrate correlations between the measurements at the two different resolutions, reveal the physical basis for these correlations, and demonstrate that the data from the low-resolution scan can be used to estimate the variation in (small-scale) cell geometry throughout a structural-size piece of wood.This work was funded in major part by a Leverhulme Trust Programme Grant. The X-ray imaging work was supported by the Advanced Imaging of Materials (AIM) facility (EPSRC Grant No. EP/M028267/1), the European Social Fund (ESF) through the European Union’s Convergence programme administered by the Welsh Government