Palaeoenvironmental changes recorded in the palynology and palynofacies of a Late Permian Marker Mudstone (Galilee Basin, Australia)

Reconstructing the terrestrial palaeoenvironment during the end-Permian is made challenging by widespread erosion and ecosystem destruction. High-resolution sampling for palynofacies and palynology in sections that preserve the boundary interval allows for detailed examination of the drastic environmental changes that characterize the Permian–Triassic mass extinction. In the Bowen and Galilee basins in eastern Australia, this environmental perturbation is recorded within a Marker Mudstone that occurs above the uppermost Permian coal seams. The Marker Mudstone is used as a stratigraphic reference level at many localities, but has previously only been studied at a single locality in the Bowen Basin. In the present study, borehole Tambo 1-1A drilled in the Galilee Basin was selected to clarify whether this black, organic-rich mudstone marks a marine transgression, and to examine potential indicators of the end-Permian mass extinction. A total of 22 samples were taken from the mudstone unit, and from the over- and underlying strata and processed for palynology, palynofacies, and carbon isotope analysis. Biostratigraphic data indicate that the Marker Mudstone itself covers the uppermost part of unit APP5, with the first index taxa of unit APP6 floras occurring in samples less than 80 cm above this interval. This can be correlated with several other localities in the Bowen and Sydney basins where this shift occurs just above the uppermost Permian coal seam. Palynofacies data agree with previous interpretations of a southwards prograding delta that subsides as base level rises to form an extensive waterbody in which the Marker Mudstone was deposited. A change from translucent phytoclast-dominated to opaque phytoclast-dominated palynofacies within the Marker Mudstone suggests a shift to more oxic conditions in the water column, while base level begins to fluctuate, or increased terrestrial input from fluvial systems as the hinterland rises. Algal bodies resembling Botryococcus are found in the strata above the Marker Mudstone, but differ in morphology from the algal bodies found in the deltaic facies below. The presence of acanthomorph acritarchs in the Marker Mudstone and in the overlying Rewan Formation may indicate marine influence. Forms resembling fungal spores are present, but they do not show a “spike” as seen in other P–T boundary localities. The relative position of unit APP6 to the P–T boundary itself remains unclear. APP6 assemblages are dominated by simple acavate trilete and cavate trilete spores, which suggests stressed environment dominated by ferns and lycopods. The presence of degraded phytoclasts towards the top of the Marker Mudstone may also be used to suggest a mass-extinction interval. They may also be indicative of shifting local palaeoenvironmental changes, an interpretation that is supported by the low magnitude negative excursion of the δC isotope values within the Marker Mudstone. More datasets from the Bowen and Galilee basins will be essential to decoupling these signals

Oil and the Porcupine Caribou Herd — Can we quantify the impacts?

We report on a number of ongoing studies and discuss what projects are in place to further refine and test relationships

Pregnancy rate as an indicator of nutritional status in Rangifer. implications of lactational infertility

Monitofing pregnancy rates to detect changes in nutrition is best accomplished by sampling lactating females because they will be more responsive to changes in nutrienr availability: nutrition influences pregnancy fate of lactating caribou both through autumn body condition and lactational infertility

Mechanism and reaction coordinate of directional charge separation in bacterial reaction centers

Solid state NMR/Biophysical Organic Chemistr

A nationwide Dutch cohort study shows relatively good pregnancy outcomes after kidney transplantation and finds risk factors for adverse outcomes

Although numbers of pregnancy after kidney transplantation (KT) are rising, high risks of adverse pregnancy outcomes (APO) remain. Though important for pre-conception counselling and pregnancy monitoring, analyses of pregnancy outcomes after KT per pre-pregnancy estimated glomerular filtration rate-chronic kidney disease (eGFR-CKD)-categories have not been performed on a large scale before. To do this, we conducted a Dutch nationwide cohort study of consecutive singleton pregnancies over 20 weeks of gestation after KT. Outcomes were analyzed per pre-pregnancy eGFR-CKD category and a composite APO (cAPO) was established including birth weight under 2500 gram, preterm birth under 37 weeks, third trimester severe hypertension (systolic blood pressure over 160 and/or diastolic blood pressure over 110 mm Hg) and/or over 15% increase in serum creatinine during pregnancy. Risk factors for cAPO were analyzed in a multilevel model after multiple imputation of missing predictor values. In total, 288 pregnancies in 192 women were included. Total live birth was 93%, mean gestational age 35.6 weeks and mean birth weight 2383 gram. Independent risk factors for cAPO were pre-pregnancy eGFR, midterm percentage serum creatinine dip and midterm mean arterial pressure dip; odds ratio 0.98 (95% confidence interval 0.96–0.99), 0.95 (0.93-0.98) and 0.94 (0.90-0.98), respectively. The cAPO was a risk indicator for graft loss (hazard ratio 2.55, 1.09-5.96) but no significant risk factor on its own when considering pre-pregnancy eGFR (2.18, 0.92-5.13). This was the largest and most comprehensive study of pregnancy outcomes after KT, including pregnancies in women with poor kidney function, to facilitate individualized pre-pregnancy counselling based on pre-pregnancy graft function. Overall obstetric outcomes are good. The risk of adverse outcomes is mainly dependent on pre-pregnancy graft function and hemodynamic adaptation to pregnancy

Recombinant Modified Vaccinia Virus Ankara Expressing Glycoprotein E2 of Chikungunya Virus Protects AG129 Mice against Lethal Challenge

Chikungunya virus (CHIKV) infection is characterized by rash, acute high fever, chills, headache, nausea, photophobia, vomiting, and severe polyarthralgia. There is evidence that arthralgia can persist for years and result in long-term discomfort. Neurologic disease with fatal outcome has been documented, although at low incidences. The CHIKV RNA genome encodes five structural proteins (C, E1, E2, E3 and 6K). The E1 spike protein drives the fusion process within the cytoplasm, while the E2 protein is believed to interact with cellular receptors and therefore most probably constitutes the target of neutralizing antibodies. We have constructed recombinant Modified Vaccinia Ankara (MVA) expressing E3E2, 6KE1, or the entire CHIKV envelope polyprotein cassette E3E26KE1. MVA is an appropriate platform because of its demonstrated clinical safety and its suitability for expression of various heterologous proteins. After completing the immunization scheme, animals were challenged with CHIV-S27. Immunization of AG129 mice with MVAs expressing E2 or E3E26KE1 elicited neutralizing antibodies in all animals and provided 100% protection against lethal disease. In contrast, 75% of the animals immunized with 6KE1 were protected against lethal infection. In conclusion, MVA expressing the glycoprotein E2 of CHIKV represents as an immunogenic and effective candidate vaccine against CHIKV infections

A human colonic crypt culture system to study regulation of stem cell-driven tissue renewal and physiological function

The intestinal epithelium is one of the most rapidly renewing tissues in the human body and fulfils vital physiological roles such as barrier function and transport of nutrients and fluid. Investigation of gut epithelial physiology in health and disease has been hampered by the lack of ex vivo models of the native human intestinal epithelium. Recently, remarkable progress has been made in defining intestinal stem cells and in generating intestinal organoid cultures. In parallel, we have developed a 3D culture system of the native human colonic epithelium that recapitulates the topological hierarchy of stem cell-driven tissue renewal and permits the physiological study of native polarized epithelial cells. Here we describe methods to establish 3D cultures of intact human colonic crypts and conduct real-time imaging of intestinal tissue renewal, cellular signalling, and physiological function, in conjunction with manipulation of gene expression by lentiviral or adenoviral transduction. Visualization of mRNA- and protein-expression patterns in cultured human colonic crypts, and cross-validation with crypts derived from fixed mucosal biopsies, is also described. Alongside studies using intestinal organoids, the near-native human colonic crypt culture model will help to bridge the gap that exists between investigation of colon cancer cell lines and/or animal (tissue) studies, and progression to clinical trials. To this end, the near native human colonic crypt model provides a platform to aid the development of novel strategies for the prevention of inflammatory bowel disease and cancer

DNA methylation dynamics during intestinal stem cell differentiation reveals enhancers driving gene expression in the villus

Background: DNA methylation is of pivotal importance during development. Previous genome-wide studies identified numerous differentially methylated regions upon differentiation of stem cells, many of them associated with transcriptional start sites. Results: We present the first genome-wide, single-base-resolution view into DNA methylation dynamics during differentiation of a mammalian epithelial stem cell: the mouse small intestinal Lgr5+ stem cell. Very little change was observed at transcriptional start sites and our data suggest that differentiation-related genes are already primed for expression in the stem cell. Genome-wide, only 50 differentially methylated regions were identified. Almost all of these loci represent enhancers driving gene expression in the differentiated part of the small intestine. Finally, we show that binding of the transcription factor Tcf4 correlates with hypo-methylation and demonstrate that Tcf4 is one of the factors contributing to formation of differentially methylated regions. Conclusions: Our results reveal limited DNA methylation dynamics during small intestine stem cell differentiation and an impact of transcription factor binding on shaping the DNA methylation landscape during differentiation of stem cells in vivo

Impact of cross-enterprise data sharing on portable media with decentralised upload of DICOM data into PACS

OBJECTIVES: To evaluate portable media utilisation for image data sharing between enterprises. To predict the costs required to keep up with the trend. To identify related problems. METHODS: A software package was developed to include patient image data from CD into our normal workflow. The trend in the workload of CDs that were uploaded into a Picture Archiving and Communication System (PACS) over 89 months was analysed. The average number of images per month (and per investigation) was calculated to provide the estimation of storage and cost required in the whole process. RESULTS: All Digital Imaging and Communications in Medicine (DICOM) files can be read from compact disc (CD) on any workstation in the hospital, processed quickly to the central server and checked after storage using the software tool. A total of 33,982,404 images from 88,952 CDs have been stored into the PACS system. In recent years, the stored images have reached an average of 4.2 terabytes (TB) uncompressed annually. CONCLUSION: Integrated information about patients is clearly needed to provide easy and timely access to these data. The steadily growing storage can be solved by a more automated approach to portable media handling or the installation and acceptance of network-based transfer using cross-enterprise document sharing (XDS). KEY POINTS: • Rapid assimilation of external imaging into a PACS system is essential. • But data distribution using portable media also carries some disadvantages. • A DICOM data uploader incorporates studies from portable media to hospital workflow. • Automated media handling or XDS should solve the steadily growing storage problem. • Software improvements will facilitate the steady increase in the amount of CDs processed