NanoPET imaging of [18F]fluoromisonidazole uptake in experimental mouse tumours

Purpose: The purpose of this study was to assess the potential and utility of ultra-high-resolution hypoxia imaging in various murine tumour models using the established hypoxia PET tracer [18F]fluoromisonidazole ([18F]FMISO). Methods: [18F]FMISO PET imaging was performed with the dedicated small-animal PET scanner NanoPET (Oxford Positron Systems) and ten different human tumour xenografts in nude mice as well as B16 melanoma tumours in syngeneic Balb/c mice. For comparison, [18F]fluorodeoxyglucose ([18F]FDG) PET scans were also performed in the mice bearing human tumour xenografts. Results: In 10 out of 11 experimental tumour models, [18F]FMISO PET imaging allowed clear-cut visualisation of the tumours. Inter- and intratumoural heterogeneity of tracer uptake was evident. In addition to average TMRR (tumour-to-muscle retention ratio including all voxels in a volume of interest (VOI)), the parameters TMRR75% and TMRR5 (tumour-to-muscle retention ratio including voxels of 75% or more of the maximum radioactivity in a VOI and the five hottest pixels, respectively) also served as measures for quantifying the heterogeneous [18F]FMISO uptake in the tumours. The variability observed in [18F]FMISO uptake was related neither to tumour size nor to the injected mass of the radiotracer. The pattern of normoxic and hypoxic regions within the human tumour xenografts, however, correlated with glucose metabolism as revealed by comparison of [18F]FDG and [18F]FMISO images. Conclusion: This study demonstrates the feasibility and utility of [18F]FMISO for imaging murine tumour models using NanoPE

Vascular Flora of the Glass Mountain Region, Mono County, California

The purpose of this study is to document the vascular flora of the Glass Mountain region of Mono County, California. Little focused botanical attention has been given to this remote volcanic mountain range between the Sierra Nevada and White Mountains of eastern California. The majority of collecting in the area was done from the 1960s through 1998 by Dean W. Taylor, Mary DeDecker, and Jack Reveal, providing good documentation of a few scattered localities of the range. This study circumscribes a large area around the Glass Mountain range, and attempts to catalog the diversity of vascular plants with vouchered collections from many habitat types throughout the region. Field collecting and herbarium searches done from 1999 through 2002 have yielded 489 taxa (species, infraspecific taxa, and hybrids), building on the foundation of 181 taxa previously documented from the area. Sampling was done from low saltgrass meadows, through sagebrush series, into subalpine forests and meadows, and onto arid alpine peaks and ridges. An Annotated Catalog of the Flora lists the diversity of vascular plants documented in the region thus far. Vegetation descriptions, botanical collection history, numerical summaries, sensitive plants, and comparisons with other nearby floras are presented

Complexer-YOLO: Real-Time 3D Object Detection and Tracking on Semantic Point Clouds

Accurate detection of 3D objects is a fundamental problem in computer vision and has an enormous impact on autonomous cars, augmented/virtual reality and many applications in robotics. In this work we present a novel fusion of neural network based state-of-the-art 3D detector and visual semantic segmentation in the context of autonomous driving. Additionally, we introduce Scale-Rotation-Translation score (SRTs), a fast and highly parameterizable evaluation metric for comparison of object detections, which speeds up our inference time up to 20\% and halves training time. On top, we apply state-of-the-art online multi target feature tracking on the object measurements to further increase accuracy and robustness utilizing temporal information. Our experiments on KITTI show that we achieve same results as state-of-the-art in all related categories, while maintaining the performance and accuracy trade-off and still run in real-time. Furthermore, our model is the first one that fuses visual semantic with 3D object detection

The Domestic and Export Market for Large Scale Wave Energy in Ireland and the Economics of Export Transmission

Ireland is on track to meet its 2020 renewable energy targets with over 2 GW of onshore wind installed in the all island market as of 2013, and a multiple of this capacity in various stages of planning and development. It is currently unclear how much of this potential capacity will ultimately be installed but it has become clear that the wind industry in Ireland will change focus to export opportunities post 2020. This presents some interesting challenges for wave energy in Ireland. There is some early activity in the installation of wave farms off the west coast of Ireland and it is evident that the potential resource is extremely large. This wave resource is concentrated on the west coast of Ireland, remote of domestic load centres and export markets. To fully exploit this resource the wave energy industry may ultimately depend on the export market opportunity due to limited domestic demand. This paper examines the domestic potential for wave energy penetration and the benefits this may bring. It is concluded that there is a potential domestic market for wave energy in Ireland with the right conditions, although this market may be limited. Ultimately it is concluded that large scale wave energy may require a transmission route to an export market and this will be challenging and expensive, requiring the use o

Whole animal copper flux assessed by positron emission tomography in the Long - Evans cinnamon rat - a feasibility study

Copper is an essential trace element. However, excess copper can lead to oxidation of biomolecules and cell damage and copper levels must be carefully controlled. While copper homeostasis has been studied extensively at the cellular level, short-term body copper fluxes are poorly understood. Here, we assessed for the first time the feasibility of measuring whole body copper flux by positron emission tomography, using 64Cu. A comparative approach comparing the Long - Evans cinnamon (LEC) rat to the wild type was chosen. LEC rats are an accepted model for Wilson disease, an inherited disorder of copper excretion in humans. In LEC rats as well as in Wilson patients, the copper transporting ATPase, ATP7B, is defective. This ATPase is primarily expressed in the liver and serves in copper secretion via the bile. Dysfunction of ATP7B leads to accumulation of copper in the liver. A control and an LEC rat were transgastrically injected with 10 μg of 64Cu and the copper flux followed for three hours by whole animal PET and concomitant collection of bile, as well as the analysis of tissue following tomography. As seen by PET, the administered copper was largely trapped in the stomach and the proximal intestine, and without a significant difference between control and LEC rat. Due to an insufficient dynamic range of the PET technology, copper which was systemically absorbed and primarily transported to the liver could only be followed by sampling and by β-counting. Biliary copper excretion ensued after 15 min in the control rat, but was absent in the LEC rat. Biliary excretion reached saturation one hour after copper administration. The trapping of orally administered copper in the gastrointestinal tract may be an important mechanism to prevent copper toxicity under conditions of a sudden, excessive copper load, which cannot be alleviated by increased biliary secretion. This trapping does however limit the utility of PET to measure whole animal copper flu

Primeira descrição de Cooperia spatulata Baylis, 1938 em bovinos no Estado do Rio de Janeiro

In 40 calves slaughtered at the National Centre for Dairy Cattle Research (CNPGL) EMBRAPA, at Marquês de Valença, state of Rio de Janeiro, Brazil, Cooperia spatuleta (Baylis, 1938) was identified for the first time as a parasite of bovines in Brazil.Utilizando-se 40 bezerros provenientes da Estação Experimental Santa Mônica do Centro Nacional de Pesquisa de Gado de Leite - CNPGL da Empresa Brasileira de Pesquisa Agropecuária - EMBRAPA, localizada no município de Marquês de Valença, Estado do Rio de Janeiro, realizaram-se necrópsias, nas quais foi identificada a espécie Cooperta spatulata Baylis, 1938, salientando-se que ela é assinalada pela primeira vez no Brasil

Produção de ovos de nematódeos gastrintestinais em vacas Nelore, durante o período periparto

An evaluation was made of the influence of the peri-parturient period on the counts of eggs of nematodes in the faeces of beef cattle. Thirty-two Nellore pregnant cows were used, of which 8 with the first calf, 12 with the second and 12 with the third calf, all calving in October. To determine the number of eggs per gram of faeces (EPG) and larvaecultures, one sample of faeces was collected before calving (aproximately fifteen days before), one sample at calving and six weekly samples post calving. There was no significant interaction between the number of calves and the EPG counts in the different samples. No significant difference was observed in the EPG counts before and after calving, although there was a tendency to an increase on the day of calving and during two weeks afterwards. Cows with first calf showed mean EPG higher than those with second and third calves, both before and after calving (P<0.05). Cooperia sp. contributed most to the rise in mean EPG. Taking into consideration the increase in EPG of cows, and epidemiological studies previously carried out, it is recommended that cows be dosed in the months of July or August.Foi avaliada a influência das épocas de pré e pós-parto sobre a contagem de ovos de nematódeos nas fezes de bovinos de corte. Utilizaram-se 32 vacas Nelore prenhes, sendo 8 de primeira, 12 de segunda e 12 de terceira cria, como parto previsto para o mês de outubro. Para determinação do número de ovos por grama de fezes (OPG) e coproculturas, foi feita uma coleta de fezes antes do parto (aproximadamente quinze dias antes), uma por ocasião do parto e seis coletas semanais após o parto. Não houve interação significativa entre o número de crias das vacas com os valores de OPG nas diferentes coletas. Não foi observada diferença significativa, nos valores de OPG, antes e depois do parto, apesar de ter havido uma tendência de aumento no dia do parto e nas duas semanas após o parto. As vacas de primeira cria apresentaram média de OPG maiores do que as vacas de segunda e terceira crias, tanto antes como depois do parto (P<0,05). A Cooperia foi o nematódeo que mais contribuiu para o aumento de OPG. Levando-se em consideração o aumento de OPG das vacas e estudos epidemiológicos anteriores, é recomendada a dosificação das vacas no mês de julho ou agosto

18F-choline in experimental soft tissue infection assessed with autoradiography and high-resolution PET

For each oncological tracer it is important to know the uptake in non-tumorous lesions. The purpose of this study was to measure the accumulation of fluorine-18 choline (FCH), a promising agent for the evaluation of certain tumour types, in infectious tissue. Unilateral thigh muscle abscesses were induced in five rats by intramuscular injection of 0.1ml of a bacterial suspension (Staphylococcus aureus, 1.2×109CFU/ml). In all animals, FCH accumulation was measured with high-resolution positron emission tomography (PET) on day 6. Autoradiography of the abscess and ipsilateral healthy muscle was performed on day 7 (three animals) and day 11 (two animals) and correlated with histology. In addition, 18F-fluorodeoxyglucose (FDG) PET was performed on day 5. Increased FCH uptake was noted in specific layers of the abscess wall which contained an infiltrate of mainly granulocytes on day 7 and mainly macrophages on day 11. The autoradiographic standardised uptake values in the most active part of the abscess wall were 2.99 on day 7 (n=3) and 4.05 on day 11 (n=2). In healthy muscle the corresponding values were 0.99 and 0.64. The abscesses were clearly visualised on the FCH and FDG PET images. In conclusion, this study demonstrated avid FCH accumulation in inflammatory tissue, which limits the specificity of FCH for tumour detection. Future studies are now needed to determine the degree of this limitation in human cancer patient

18F-AV-1451 tau PET imaging correlates strongly with tau neuropathology in MAPT mutation carriers

Tau positron emission tomography ligands provide the novel possibility to image tau pathology in vivo. However, little is known about how in vivo brain uptake of tau positron emission tomography ligands relates to tau aggregates observed post-mortem. We performed tau positron emission tomography imaging with 18F-AV-1451 in three patients harbouring a p.R406W mutation in the MAPT gene, encoding tau. This mutation results in 3- and 4-repeat tau aggregates similar to those in Alzheimer's disease, and many of the mutation carriers initially suffer from memory impairment and temporal lobe atrophy. Two patients with short disease duration and isolated memory impairment exhibited 18F-AV-1451 uptake mainly in the hippocampus and adjacent temporal lobe regions, correlating with glucose hypometabolism in corresponding regions. One patient died after 26 years of disease duration with dementia and behavioural deficits. Pre-mortem, there was 18F-AV-1451 uptake in the temporal and frontal lobes, as well as in the basal ganglia, which strongly correlated with the regional extent and amount of tau pathology in post-mortem brain sections. Amyloid-β (18F-flutemetamol) positron emission tomography scans were negative in all cases, as were stainings of brain sections for amyloid. This provides strong evidence that 18F-AV-1451 positron emission tomography can be used to accurately quantify in vivo the regional distribution of hyperphosphorylated tau protein