Stimulation of TM3 Leydig cell proliferation via GABA(A )receptors: A new role for testicular GABA

The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABA(A )and GABA(B )receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABA(A )receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABA(A )receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABA(A )receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA) we demonstrated that GABA or the GABA(A )agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABA(A )antagonist bicuculline, implying a role for GABA(A )receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABA(A )receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment

Energy Consumption In Non-Domestic Buildings: A Review of Schools

Abstract: The energy consumption associated with non-domestic buildings represents 11% of the UK's total energy consumption, 11% of Europe and 18% of the USA's. A nnual non-domestic building energy consumption is often presented in the form of average benchmarks, such as 450kWh/m²/year for a large airconditioned building and 200kWh/m²/year for a small naturally ventilated office. Benchmark values give very little insight into how and where a building consumes energy. While some benchmarks provide a breakdown of energy use by energy category (lights, IT, cooling, heating), these data still fails to demonstrate how the energy associated with each category varies throughout the year. To further understand building energy use, a more detailed data breakdown and analysis is required. The electricity demand data for a variety of school buildings (secondary, primary, specialised) in Scotland has been made available for analysis. This consists of half hourly resolution data spanning several years for 50 s chools, allowing key trends and patterns in energy use to be identified. T hese trends can include differences between annual profiles, differences between winter and summer months, and differences in weekday and weekend energy use. Additionally, the effect of other variables such as climate, user behaviour and general building data on the buildings energy consumption can be investigated. A database of half-hourly school energy demand data, with corresponding building details has been set up and a preliminary analysis preformed. Alternative method of pattern recognition in non-domestic energy usage are discussed, and the variables necessary to calibrate this information. This demonstrates the possibility of creating generic energy profiles and hence new benchmarks

Uptake of home-based voluntary HIV testing in sub-Saharan Africa: a systematic review and meta-analysis

Improving access to HIV testing is a key priority in scaling up HIV treatment and prevention services. Home-based voluntary counselling and testing (HBT) as an approach to delivering wide-scale HIV testing is explored here

Coastal restoration success via emergent trait-mimicry is context dependent

Coastal ecosystems provide vital ecosystem functions and services, but have been rapidly degrading due to human impacts. Restoration is increasingly considered key to reversing these losses, but is often unsuccessful. Recent work on seagrasses and salt marsh cordgrasses highlights that restoration yields can be greatly enhanced by temporarily mimicking key emergent traits. These traits are not expressed by individual seedlings or small clones, but emerge in clumped individuals or large clones to locally suppress environmental stress, causing establishment thresholds where such density-dependent self-facilitation is important for persistence. It remains unclear, however, to what extent the efficacy of restoration via emergent trait-based mimicry depends on the intensity of stressors. We test this in a restoration experiment with the temperate seagrass Zostera marina at four sites (Finland, Sweden, UK, USA) with contrasting hydrodynamic regimes, where we simulated dense roots mats or vegetation canopies with biodegradable structural mimics. Results show that by mimicking sediment-stabilizing root mats, seagrass transplant survival, growth and expansion was strongly enhanced in hydrodynamically exposed environments. However, these positive effects decreased and turned negative under benign conditions, while mimics insufficiently mitigated physical stress in extremely exposed environments, illustrating upper and lower limits of the application. Furthermore, we found that aboveground structures, designed to mimic stiff rather than flexible vegetation canopies, underperformed compared to belowground mimics. Our findings emphasize the importance of understanding the conditions at the restoration site, species-specific growth requirements, and self-facilitating traits that organisms may express when applying emergent trait-mimicry as a tool to improve restoration success

Incidence and Reproduction Numbers of Pertussis: Estimates from Serological and Social Contact Data in Five European Countries

Analyses of serological and social contact data from several European countries by Miriam Kretzschmar and colleagues show that vaccination against pertussis has shifted the burden of infection from children to adolescents and adults

New insights into measurement variability in glaucomatous visual fields from computer modelling.

To develop a model to simulate visual fields (VFs) in glaucoma patients, and to characterize variability of the Mean Deviation (MD) VF summary measurement using real VFs and simulations

The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) family

The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) enzymes are secreted, multi-domain matrix-associated zinc metalloendopeptidases that have diverse roles in tissue morphogenesis and patho-physiological remodeling, in inflammation and in vascular biology. The human family includes 19 members that can be sub-grouped on the basis of their known substrates, namely the aggrecanases or proteoglycanases (ADAMTS1, 4, 5, 8, 9, 15 and 20), the procollagen N-propeptidases (ADAMTS2, 3 and 14), the cartilage oligomeric matrix protein-cleaving enzymes (ADAMTS7 and 12), the von-Willebrand Factor proteinase (ADAMTS13) and a group of orphan enzymes (ADAMTS6, 10, 16, 17, 18 and 19). Control of the structure and function of the extracellular matrix (ECM) is a central theme of the biology of the ADAMTS, as exemplified by the actions of the procollagen-N-propeptidases in collagen fibril assembly and of the aggrecanases in the cleavage or modification of ECM proteoglycans. Defects in certain family members give rise to inherited genetic disorders, while the aberrant expression or function of others is associated with arthritis, cancer and cardiovascular disease. In particular, ADAMTS4 and 5 have emerged as therapeutic targets in arthritis. Multiple ADAMTSs from different sub-groupings exert either positive or negative effects on tumorigenesis and metastasis, with both metalloproteinase-dependent and -independent actions known to occur. The basic ADAMTS structure comprises a metalloproteinase catalytic domain and a carboxy-terminal ancillary domain, the latter determining substrate specificity and the localization of the protease and its interaction partners; ancillary domains probably also have independent biological functions. Focusing primarily on the aggrecanases and proteoglycanases, this review provides a perspective on the evolution of the ADAMTS family, their links with developmental and disease mechanisms, and key questions for the future

iSchools and archival studies

Whispers and rumors about the iSchool movement lead some to fear that this represents yet another shift away from the valued traditions of library schools, threatening something far different than what library science pioneers ever envisioned. Predating the iSchool movement, however, were other programmatic shifts such as those that led to the formalization of graduate archival education. This essay argues that such evolution is essential to our future, as iSchools tackle the increasingly complex issues confronting a digital society. We consider the mission and history of iSchools and of archival studies, the basic elements and concepts of archival studies that are critical to iSchools, and the relationship between iSchools and the changing nature of personal and institutional archives. © 2009 Springer Science+Business Media B.V