Adenovirus Type 40 Host Range in Tissue Culture: A Study of the E1B Region

Growth restriction in tissue culture is a distinct feature of the enteric adenoviruses and they differ in this respect from all other subgroups of human adenoviruses. Ad40 cannot be passaged on Hela cells or primary HEK cells, but will grow in cells expressing the E1 region or only the E1B region of Ad2 or Ad5. The work described here was aimed at understanding the basis for this growth restriction. In coinfection experiments Ad40 complements an Ad5 E1A mutant and is itself complemented by that mutant as well as Ad5 and Adl2 wild type and E1B 19K mutant viruses. Ad5 and Ad12 E1B 55K mutant viruses are complemented to some extent by Ad40, these mutants however do not complement Ad40 growth on Hela cells. In order to study the E1B region of Ad40 a transcription map was determined from RNA produced at late times in infected KBa+b cells, using S1 nuclease, primer extension and PCR-cDNA analysis as well as Northern blotting. E1B transcripts corresponding to Ad2 14S, 22S and 9S mRNAs were identified but no 13S mRNA equivalent was detected, a pattern similar to that seen in the Adl2 transcription map. The coding potential for E1B 19K, 55K, and 15K proteins and for ppIX is retained in the Ad40 transcripts. In addition novel E1A-E1B cotranscript counterparts of the 14S and 22S mRNAs were identified. These contain the first 40 codons of the E1A first exon linked to a site 4-5nt downstream of the E1B cap site, retaining all the coding potential of the E1B mRNAs. No new open reading frames are created by the junction, and the E1A ORF terminates with one codon added after the junction. The E1A-E1B junction is unusual in that it does not conform to splice consensus sequences and thus may not be generated by a conventional splicing mechanism. Sequences around the 5' site of the junction bear a certain resemblance to spliced leader sequences utilized in trans-splicing in trypanosomes and nematodes. A timecourse of E1 transcription and DNA replication confirmed that. E1B transcripts are not detectable at early times in infection, but appear around the onset of DNA replication. The E1A-E1B cotranscripts are first seen at the same time as transcripts from the E1B promoter. Transcription from the Ad40 E1B promoter was analysed in transient transfection assays. Chloramphenicol acetyl transferase (CAT) activity was measured in cell extracts where the CAT gene was expressed under the control of the E1B promoter in the presence or absence of E1A products of Ad5 or Ad40. Expression from the Ad40 E1B promoter was not detectable even in the presence of Ad5 E1A, suggesting that unlike its Ad5 counterpart the Ad40 E1B promoter does not respond to E1A transactivation. This would account for the lack of early E1B gene expression in tissue culture. Moreover, this suggests that in the natural host cells of the virus E1B early gene products may not be needed, or alternatively, that early expression from the Ad40 E1B promoter is dependent on cellular factors present in the natural host cell, but absent in most common tissue culture cell lines. In this study Ad40 was shown to grow in an intestinal cell line, Int407, almost as well as in KB cells expressing the Ad2 E1 region. This provides a system in which to study Ad40 growth in tissue culture in the absence of complementing viral gene products

Comparison of aneroid and oscillometric blood pressure measurements in children.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.Limited data exist on the comparison of blood pressure (BP) measurements using aneroid and oscillometric devices. The purpose of the study was to investigate the difference in BP obtained using oscillometric and aneroid BP monitors in 9- to 10-year-old children. A total of 979 children were divided into group O, which underwent two oscillometric BP readings followed by two aneroid readings, and group A, which had BP measured in the reverse order. No significant difference was found between the mean (±standard deviation) of the two systolic BP readings obtained using the oscillometric and aneroid devices (111.5±8.6 vs 111.3±8.1 mm Hg; P=.39), whereas the mean diastolic BP was lower with the oscillometric monitor (61.5±8.0 vs 64.5±6.8 mm Hg; P<.001). A significant downward trend in BP was observed with each consecutive measurement, and agreement between the two monitors was limited. Multiple BP measurements are, therefore, recommended before the diagnosis of elevated BP or hypertension is made with either method.Landspitali - The National University Hospital of Iceland Research Fun

Paleo-leaf economics reveal a dramatic shift in ecosystem function associated with the end-Triassic mass extinction event

Climate change is likely to have altered the ecological functioning of past ecosystems, and is likely to alter functioning in the future; however, the magnitude and direction of such changes are difficult to predict. Here we use a deep-time case study to evaluate the impact of a well-constrained CO2-induced global warming event on the ecological functioning of dominant plant communities. We use leaf mass per area (LMA), a widely used trait in modern plant ecology, to infer the palaeoecological strategy of fossil plant taxa. We show that palaeo-LMA can be inferred from fossil leaf cuticles based on a tight relationship between LMA and cuticle thickness observed among extant gymnosperms. Application of this new palaeo-LMA proxy to fossil gymnosperms from East Greenland reveals significant shifts in the dominant ecological strategies of vegetation found across the Triassic–Jurassic transition. Late Triassic forests, dominated by low-LMA taxa with inferred high transpiration rates and short leaf lifespans, were replaced in the Early Jurassic by forests dominated by high-LMA taxa that were likely to have slower metabolic rates. We suggest that extreme CO2-induced global warming selected for taxa with high LMA associated with a stress-tolerant strategy and that adaptive plasticity in leaf functional traits such as LMA contributed to post-warming ecological success

Hässeldala – a key site for Last Termination climate events in northern Europe

The Last Termination (19 000–11 000 a BP) with its rapid and distinct climate shifts provides a perfect laboratory to study the nature and regional impact of climate variability. The sedimentary succession from the ancient lake at Hässeldala Port in southern Sweden with its distinct Lateglacial/early Holocene stratigraphy (&gt;14.1–9.5 cal. ka BP) is one of the few chronologically well‐constrained, multi‐proxy sites in Europe that capture a variety of local and regional climatic and environmental signals. Here we present Hässeldala's multi‐proxy records (lithology, geochemistry, pollen, diatoms, chironomids, biomarkers, hydrogen isotopes) in a refined age model and place the observed changes in lake status, catchment vegetation, summer temperatures and hydroclimate in a wider regional context. Reconstructed mean July temperatures increased between c. 14.1 and c. 13.1 cal. ka BP and subsequently declined. This latter cooling coincided with drier hydroclimatic conditions that were probably associated with a freshening of the Nordic Seas and started a few hundred years before the onset of Greenland Stadial 1 (c. 12.9 cal. ka BP). Our proxies suggest a further shift towards colder and drier conditions as late as c. 12.7 cal. ka BP, which was followed by the establishment of a stadial climate regime (c. 12.5–11.8 cal. ka BP). The onset of warmer and wetter conditions preceded the Holocene warming over Greenland by c. 200 years. Hässeldala's proxies thus highlight the complexity of environmental and hydrological responses across abrupt climate transitions in northern Europe

Key traits of living fossil Ginkgo biloba are highly variable but not influenced by climate – Implications for palaeo-pCO2 reconstructions and climate sensitivity

The Ginkgoales, including the ‘living fossil’ Ginkgo biloba, are an important group for stomata-based palaeo-pCO2 reconstructions, with long evolutionary lineages and an extensive, abundant fossil record. The stomatal proxy for palaeo-pCO2 can improve our understanding of the exact relationship between pCO2 and temperatures – Earth's climate sensitivity: a key measure of global warming by pCO2. However, pCO2 records from future climate analogues in the past, such as the mid-Miocene Climatic Optimum, seemingly underestimate pCO2 – climate models cannot simulate the past temperatures with the only moderately elevated pCO2 reconstructed by proxies. Either climate sensitivity must have been elevated, which has implications for future climate forecasts, or proxies underestimate pCO2 due to additional environmental factors. Here we tested whether climate conditions impact stomatal parameters and thus pCO2 reconstruction on a large global database of G. biloba leaves from all continents except Antarctica, spanning 12 climate zones. We reconstructed ambient pCO2 using three stomatal proxy methods (stomatal ratio, transfer functions, Franks gas exchange model) and one stomata-independent isotope-based proxy for comparison (C3 proxy). We found that the stomatal proxy methods reconstructed ambient pCO2 reasonably well and uniformly, but that the C3 proxy underestimated pCO2. All the investigated stomatal parameters displayed an unexpectedly large variability, but no significant relationship with temperature, precipitation, or seasonality. Based on these results, the stomatal proxy is not influenced by climate and specifically does not systematically underestimate pCO2 under high temperatures. Climate sensitivity was likely instead elevated during past global warming episodes, an urgent consideration in climate forecasts for our rapidly warming Earth

Interrogating Type 2 Diabetes Genome-Wide Association Data Using a Biological Pathway-Based Approach

OBJECTIVE-Recent genome-wide association Studies have resulted in a dramatic increase in our knowledge of the genetic loci involved in type 2 diabetes. In a complementary approach to these single-marker studies, we attempted to identify biological pathways associated with type 2 diabetes. This approach could allow its to identify additional risk loci. RESEARCH DESIGN AND METHODS-We used individual level genotype data generated from the Wellcome Trust Case Control Consortium (WTCCC) type 2 diabetes study, consisting of 393,143 autosomal SNPs, genotyped across 1,924 case subjects and 2,938 control subjects. We sought additional evidence from summary level data available from the Diabetes Genetics Initiative (DGI) and the Finland-United States Investigation of NIDDM Genetics (FUSION) studies. Statistical analysis of pathways was performed using a modification of the Gene Set Enrichment Algorithm (GSEA). A total of 439 pathways were analyzed from the Kyoto Encyclopedia of Genes and Genomes, Gene Ontology, and BioCarta databases. RESULTS-After correcting for the number of pathways tested, we found no strong evidence for any pathway showing association with type 2 diabetes (top P-adj = 0.31). The candidate WNT-signaling pathway ranked top (nominal P = 0.0007, excluding TCF7L2; P = 0.002), containing a number of promising single gene associations. These include CCND2 (rs11833537; P = 0.003), SMAD3 (rs7178347; P = 0.0006), and PRICKLE1 (rs1796390; P = 0.001), all expressed in the pancreas. CONCLUSIONS-Common variants involved in type 2 diabetes risk are likely to occur in or near genes in multiple pathways. Pathway-based approaches to genome-wide association data may be more Successful for some complex traits than others, depending on the nature of the underlying disease physiology. Diabetes 58:1463-1467, 200