RNA isolation from fetal and adult human tissues for transcriptional profiling

Investigations involving rare human tissues that are difficult to acquire due to their scarcity are highly challenging. The need to verify microarray analysis data by additional methods such as immunohistochemical staining and quantitative PCR creates an even greater demand for these valuable tissues. Furthermore, since rare human tissues may come from different sources and may have been processed by variable methods, the comparability of these samples must be verified. The aim of this study was to determine and validate a processing method that allows the analysis of human fetal and adult cardiovascular tissues from different sources that were preserved using varying methods. Due to restricted access to fresh human tissues and the need to accumulate these samples over an extended period of time, we used formalin-fixed paraffin-embedded tissues for gene expression analyses. We analyzed RNA levels from four different age groups: fetal first and second trimester, adolescents, and adults. In this study, we present an improved standard processing procedure for tissue sample processing and analysis of rare human cardiovascular tissues.     

Anthropogenically modified habitats favor bigger and bolder lizards

Anthropogenic activities often create distinctive but discontinuously distributed habitat patches with abundant food but high risk of predation. Such sites can be most effectively utilized by individuals with specific behaviors and morphologies. Thus, a widespread species that contains a diversity of sizes and behavioral types may be pre‐adapted to exploiting such hotspots. In eastern Australia, the giant (to >2 m) lizard Varanus varius (lace monitor) utilizes both disturbed (campground) and undisturbed (bushland) habitats. Our surveys of 27 sites show that lizards found in campgrounds tended to be larger and bolder than those in adjacent bushland. This divergence became even more marked after the arrival of a toxic invasive species (the cane toad, Rhinella marina) caused high mortality in larger and bolder lizards. Some of the behavioral divergences between campground and bushland lizards may be secondary consequences of differences in body size, but other habitat‐associated divergences in behavior are due to habituation and/or nonrandom mortality.     

Conserving the endangered woylie (Bettongia penicillata ogilbyi): Establishing a semi‐arid population within a fenced safe haven

Measuring and monitoring population size and growth are critical to assessing the progress and ultimately the success (or failure) of a reintroduction. The Woylie (Bettongia penicillata ogilbyi) is one of Australia's threatened critical weight range mammals. To increase the species' area of occupancy, extent of occurrence, number of sub‐populations and global population size, in addition to creating a source population for future reintroductions, a new population has been re‐established into a safe haven located within the species' former range – Mt Gibson Wildlife Sanctuary. In this paper, we document the first 3 years of the reintroduction programme, over which time 162 individuals were translocated to Mt Gibson. Specifically, we (i) provide information on survivorship, (ii) estimate changes in critical population metrics (density, population size and distribution) and (iii) look for any major habitat preferences. Survivorship of collared animals was complete (i.e. zero mortality). The most recent population estimate was in the order of 750 individuals, reflecting strong growth in population size and density. The woylie has occupied the majority of the safe haven and is well represented in all major vegetation communities. The translocation is on track to meeting the key success criteria: a self‐sustaining population of woylies with a minimum of 300 individuals.     

Using conditional power of network meta‐analysis (NMA) to inform the design of future clinical trials

Clinical trials are typically designed with an aim to reach sufficient power to test a hypothesis about relative effectiveness of two or more interventions. Their role in informing evidence‐based decision‐making demands, however, that they are considered in the context of the existing evidence. Consequently, their planning can be informed by characteristics of relevant systematic reviews and meta‐analyses. In the presence of multiple competing interventions the evidence base has the form of a network of trials, which provides information not only about the required sample size but also about the interventions that should be compared in a future trial. In this paper we present a methodology to evaluate the impact of new studies, their information size, the comparisons involved, and the anticipated heterogeneity on the conditional power (CP) of the updated network meta‐analysis. The methods presented are an extension of the idea of CP initially suggested for a pairwise meta‐analysis and we show how to estimate the required sample size using various combinations of direct and indirect evidence in future trials. We apply the methods to two previously published networks and we show that CP for a treatment comparison is dependent on the magnitude of heterogeneity and the ratio of direct to indirect information in existing and future trials for that comparison. Our methodology can help investigators calculate the required sample size under different assumptions about heterogeneity and make decisions about the number and design of future studies (set of treatments compared).