The extremophilic pharmacy:drug discovery at the limits of life

[No abstract

The extremophilic pharmacy:drug discovery at the limits of life

[No abstract

Direct evidence of the molecular basis for biological silicon transport

Diatoms are an important group of eukaryotic algae with a curious evolutionary innovation: they sheath themselves in a cell wall made largely of silica. The cellular machinery responsible for silicification includes a family of membrane permeases that recognize and actively transport the soluble precursor of biosilica, silicic acid. However, the molecular basis of silicic acid transport remains obscure. Here, we identify experimentally tractable diatom silicic acid transporter (SIT) homologues and study their structure and function in vitro, enabled by the development of a new fluorescence method for studying substrate transport kinetics. We show that recombinant SITs are Na(+)/silicic acid symporters with a 1:1 protein: substrate stoichiometry and K(M) for silicic acid of 20 μM. Protein mutagenesis supports the long-standing hypothesis that four conserved GXQ amino acid motifs are important in SIT function. This marks a step towards a detailed understanding of silicon transport with implications for biogeochemistry and bioinspired materials

Validation of a fornix depth measurer: a putative tool for the assessment of progressive cicatrising conjunctivitis

Background/aims Documentation of conjunctival forniceal foreshortening in cases of progressive cicatrising conjunctivitis (PCC) is important in ascertaining disease stage and progression. Lower fornix shortening is often documented subjectively or semi-objectively, whereas upper forniceal obliteration is seldom quantified. Although tools such as fornix depth measurers (FDMs) have been described, their designs limit upper fornix measurement. The purpose of this study was to custom-design a FDM to evaluate the upper fornix and to assess variability in gauging fornix depth. \ud \ud Methods A polymethylmethacrylate FDM was constructed using industry-standard jewellery computer software and machinery. Two observers undertook a prospective independent evaluation of central lower fornix depth in a heterogeneous cohort of patients with clinically normal and abnormal conjunctival fornices both subjectively and by using the FDM (in mm). Upper central fornix depth was also measured. Agreement was assessed using Bland–Altman plots. \ud \ud Results Fifty-one eyes were evaluated. There was 100% intraobserver agreement to within 1 mm for each observer for lower fornix measurement. The mean difference in fornix depth loss using the FDM between observer 1 and 2 was 1.19%, with 95% confidence of agreement (±2SD) of −15% to +20%. In total, 86% (44/51) of measurements taken by the two observers agreed to within 10% of total lower fornix depth (ie, ±1 mm) versus only 63% (32/51) of the subjective measurements. Mean upper fornix difference was 0.57 mm, with 95% confidence of agreement of between −2 and + 3 mm. \ud \ud Conclusions This custom-designed FDM is well tolerated by patients and shows low intraobserver and interobserver variability. This enables repeatable and reproducible measurement of upper and lower fornix depths, facilitating improved rates of detection and better monitoring of progression of conjunctival scarring

Building nature’s safety net 2011 : the state of protected areas for Australia’s ecosystems and wildlife.

This report is the third in a series with the two previous reports published in 2006 and 2008. This report details major conservation initiatives that have occurred in Australia since the last report, in which data was current to 2006, and highlights emerging issues. A major enhancement on previous reports is the inclusion of ecosystem and threatened species gap analyses, and the reporting on Australia\u27s protected area systems on both land and sea. We define a minimum standard for an adequate, representative, and comprehensive reserve system by sampling ecosystem and species level diversity. Using the latest protected area and national species and ecosystem spatial data, we quantify the gaps: those areas needing to move from the current reserve system to one which meets the minimum standard. We also use data provided by various parks agencies, from responses to a questionnaire or as published by the agencies, to detail financial investments in protected areas, and estimate the investment levels needed to fill the documented gaps. We also identify critical policy changes needed to more effectively fill the identified gaps