Oriented bounding box (OBB) hierarchies can be used instead of hierarchies based on axis‐aligned bounding boxes (AABB), providing tighter fitting to the underlying geometric structures and resulting ...in improved interference tests, such as ray‐geometry intersections. In this paper, we present a method for the fast, parallel transformation of an existing bounding volume hierarchy (BVH), based on AABBs, into a hierarchy based on oriented bounding boxes. To this end, we parallelise a high‐quality OBB extraction algorithm from the literature to operate as a standalone OBB estimator and further extend it to efficiently build an OBB hierarchy in a bottom up manner. This agglomerative approach allows for fast parallel execution and the formation of arbitrary, high‐quality OBBs in bounding volume hierarchies. The method is fully implemented on the GPU and extensively evaluated with ray intersections.
Brain injury is a major complication in neonates with complex congenital heart disease. Preliminary evidence suggests that fetuses with congenital heart disease are at greater risk for brain ...abnormalities. However, the nature and frequency of these brain abnormalities detected by conventional fetal MR imaging has not been examined prospectively. Our primary objective was to determine the prevalence and spectrum of brain abnormalities detected on conventional clinical MR imaging in fetuses with complex congenital heart disease and, second, to compare the congenital heart disease cohort with a control group of fetuses from healthy pregnancies.
We prospectively recruited pregnant women with a confirmed fetal congenital heart disease diagnosis and healthy volunteers with normal fetal echocardiogram findings who underwent a fetal MR imaging between 18 and 39 weeks gestational age.
A total of 338 fetuses (194 controls; 144 with congenital heart disease) were studied at a mean gestational age of 30.61 ± 4.67 weeks. Brain abnormalities were present in 23% of the congenital heart disease group compared with 1.5% in the control group (P < .001). The most common abnormalities in the congenital heart disease group were mild unilateral ventriculomegaly in 12/33 (36.4%) and increased extra-axial spaces in 10/33 (30.3%). Subgroup analyses comparing the type and frequency of brain abnormalities based on cardiac physiology did not reveal significant associations, suggesting that the brain abnormalities were not limited to those with the most severe congenital heart disease.
This is the first large prospective study reporting conventional MR imaging findings in fetuses with congenital heart disease. Our results suggest that brain abnormalities are prevalent but relatively mild antenatally in fetuses with congenital heart disease. The long-term predictive value of these findings awaits further study.
Several studies suggest that grey matter involvement may play a role in multiple sclerosis (MS) pathology. Diffusion tensor imaging (DTI) at 3T was used to investigate the presence of damage to the ...normal-appearing thalamus in MS and its relationship with disability.
Twenty-four patients with relapsing-remitting (RR, n = 13, age = 41.7 +/- 6.1, Expanded Disability Status Scale EDSS score = 2.2 +/- 1.2) and secondary-progressive (n = 11, age = 46.9 +/- 9.6, EDSS = 5.9 +/- 1.0) MS and 24 age- and sex-matched healthy volunteers were studied. Fractional anisotropy (FA) and mean diffusivity (MD) were measured in regions of interest of normal-appearing thalamus. We examined group differences in MD and FA and correlations between DTI-derived metrics and clinical or imaging measures of disease.
Patients with MS had higher thalamic FA (P < .0001) and MD (P = .035) than volunteers. MD values correlated with the Paced Auditory Serial Addition Task (r = -0.43, P = .034) and motor EDSS (r = 0.47, P = .021) scores. In patients with RRMS, MD values correlated with global EDSS (r = 0.75, P = .003) and motor EDSS (r = 0.68, P = .010). Correlations were found between MD values and T1 and T2 lesion load (r = 0.58, P < .05) and brain parenchymal fraction (r = -0.46, P < .05).
DTI was able to detect abnormalities in normal-appearing thalamus of patients with MS. The strength of association between thalamic DTI measures and functional impairment was in the same range as those seen with standard MR imaging disease measures. The assessment of the integrity of the thalamus with DTI is a promising metric as a marker of disease for future studies.
The brown marmorated stink bug,
(Hemiptera: Pentatomidae), is an invasive species in North America and Europe that damages many different host plants. Substantial work has been conducted on the ...genetic diversity and invasion pathways of
in some of the countries where it has been found, based on mitochondrial sequences. The main objective of the present study was to further explore the genetic diversity of invasive populations of
exploiting both mitochondrial and nuclear markers. We used two molecular markers: the mitochondrial Cytochrome Oxidase I (
) gene, an ideal standardized molecular marker for distinguishing closely related species, and the ribosomal Internal Transcribed Spacer 1 (ITS1), because only a few sequences of
exist to this point in global databases. We used specimens from eight populations from Greece, Italy, Canada, and the US. Among the 14 haplotypes retrieved based on the
gene, two of them (H162-H163) were detected for the first time. These two haplotypes were found in specimens from Canada, Italy, and the US. Concerning the ITS1 region, 24 haplotypes were identified, with 15 being unique for a sampled population. In Greece and the US, 14 and 12 haplotypes were found, respectively, with 7 and 6 of them being unique for Greece and the US, respectively. Our analysis of the nuclear genes of
indicates high genetic diversity of the invading populations in North America and Europe.
Preeclampsia (PE) adversely impacts ∼5% of pregnancies. Despite extensive research, no consistent biomarkers or cures have emerged, suggesting that different molecular mechanisms may cause clinically ...similar disease. To address this, we undertook a proteomics study with three main goals: (1) to identify a panel of cell surface markers that distinguish the trophoblast and endothelial cells of the placenta in the mouse; (2) to translate this marker set to human via the Human Protein Atlas database; and (3) to utilize the validated human trophoblast markers to identify subgroups of human preeclampsia. To achieve these goals, plasma membrane proteins at the blood tissue interfaces were extracted from placentas using intravascular silica-bead perfusion, and then identified using shotgun proteomics. We identified 1181 plasma membrane proteins, of which 171 were enriched at the maternal blood-trophoblast interface and 192 at the fetal endothelial interface with a 70% conservation of expression in humans. Three distinct molecular subgroups of human preeclampsia were identified in existing human microarray data by using expression patterns of trophoblast-enriched proteins. Analysis of all misexpressed genes revealed divergent dysfunctions including angiogenesis (subgroup 1), MAPK signaling (subgroup 2), and hormone biosynthesis and metabolism (subgroup 3). Subgroup 2 lacked expected changes in known preeclampsia markers (sFLT1, sENG) and uniquely overexpressed GNA12. In an independent set of 40 banked placental specimens, GNA12 was overexpressed during preeclampsia when co-incident with chronic hypertension. In the current study we used a novel translational analysis to integrate mouse and human trophoblast protein expression with human microarray data. This strategy identified distinct molecular pathologies in human preeclampsia. We conclude that clinically similar preeclampsia patients exhibit divergent placental gene expression profiles thus implicating divergent molecular mechanisms in the origins of this disease.
Aims: The study is aimed to verify Aperio AT2 scanner for reporting on the digital pathology platform (DP) and to validate the cohort of pathologists in the interpretation of DP for routine ...diagnostic histopathological services in Wales, United Kingdom. Materials, Methods and Results: This was a large multicenter study involving seven hospitals across Wales and unique with 22 (largest number) pathologists participating. 7491 slides from 3001 cases were scanned on Leica Aperio AT2 scanner and reported on digital workstations with Leica software of e-slide manager. A senior pathology fellow compared DP reports with authorized reports on glass slide (GS). A panel of expert pathologists reviewed the discrepant cases under multiheader microscope to establish ground truth. 2745 out of 3001 (91%) cases showed complete concordance between DP and GS reports. Two hundred and fifty-six cases showed discrepancies in diagnosis, of which 170 (5.6%) were deemed of no clinical significance by the review panel. There were 86 (2.9%) clinically significant discrepancies in the diagnosis between DP and GS. The concordance was raised to 97.1% after discounting clinically insignificant discrepancies. Ground truth lay with DP in 28 out of 86 clinically significant discrepancies and with GS in 58 cases. Sensitivity of DP was 98.07% (confidence interval CI 97.57–98.56%); for GS was 99.07% (CI 98.72–99.41%). Conclusions: We concluded that Leica Aperio AT2 scanner produces adequate quality of images for routine histopathologic diagnosis. Pathologists were able to diagnose in DP with good concordance as with GS. Strengths and Limitations of this Study: Strengths of this study - This was a prospective blind study. Different pathologists reported digital and glass arms at different times giving an ambience of real-time reporting. There was standardized use of software and hardware across Wales. A strong managerial support from efficiency through the technology group was a key factor for the implementation of the study. Limitations: This study did not include Cytopathology and in situ hybridization slides. Difficulty in achieving surgical pathology practise standardization across the whole country contributed to intra-observer variations.
Insects of the infraorder Cicadomorpha cause serious economic impact on agriculture because of pathogens’ transmission. The vector‐borne bacterium Xylella fastidiosa, which is associated with olive ...quick decline syndrome, is exclusively transmitted by insects of this infraorder and more specific by sharpshooters and spittlebugs. Efficient control practices of the insect vectors are necessary for the control of the disease in cases of outbreaks. Therefore, the knowledge of the vectors' species as well as the robust understanding of their biology and ecology is of crucial importance. In the present study, extensive sampling was conducted in 28 olive orchards of Greece during the years 2017 and 2018 aiming to investigate which species of this infraorder are present, with special interest to those which are considered as vectors of the bacterium. During the surveys, 4,350 Cicadomorpha insects were collected. Forty‐two, five and one species of the families Cicadellidae, Aphrophoridae and Cercopidae, respectively, were identified. The results of the surveys revealed that the main potential vectors of X. fastidiosa in Greek olive orchards are the spittlebugs Philaenus spumarius and Neophilaenus campestris. Those species have wide distribution in Greece and are present for a long period during the year, and they inhabit both the ground vegetation and the olive trees' canopy. A representative portion of the captured spittlebugs was analysed with molecular methods, and the analysis confirmed the absence of X. fastidiosa in the tested individuals.
The insulin-like growth factor-1 (IGF-1) signaling axis is important for cell growth, differentiation and survival and increased serum IGF is a risk factor for prostate and other cancers. To study ...IGF-1 action on the prostate, we created transgenic (PB-Des) mice that specifically express human IGF-1(des) in prostate epithelial cells. This encodes a mature isoform of IGF-1 with decreased affinity for IGF binding proteins (IGFBP) due to a 3-amino acid deletion in the N terminus. Expression of IGF-1(des) was sufficient to cause hyperplastic lesions in all mice, however the well-differentiated lesions did not progress to adenocarcinoma within a year. Remarkably, crossing the PB-Des mice to an established model of prostate cancer delayed progression of organ-confined tumors and emergence of metastatic lesions in young mice. While dissemination of metastatic lesions was widespread in old bigenic mice we did not detect IGF-1(des) in poorly differentiated primary tumors or metastatic lesions. Expression of endogenous IGF-1 and levels of P-Akt and P-Erk were reduced independent of age. These data suggest that increased physiologic levels of IGF-1 facilitate the emergence of hyperplastic lesions while imposing a strong IGF-1-dependent differentiation block. Selection against IGF-1 action appears requisite for progression of localized disease and metastogenesis.
Macrolophus pygmaeus and M. melanotoma (Hemiptera: Miridae) are biological control agents used in greenhouse crops, the former preferring plants of the Solanaceae family and the latter the aster ...Dittrichia viscosa. The discrimination of these species is of high significance for effective biological pest control, but identification based on morphological characters of the host plant is not always reliable. In this study, sequencing analysis of mitochondrial gene segments 12S rDNA and COI has been combined with crossing experiments and morphological observations to develop new markers for Macrolophus spp. discrimination and to provide new data on their genetic variability. This is the first comprehensive research in Greece on M. pygmaeus and M. melanotoma genetic variability based on sequencing data from 12S rDNA and COI gene segments. The relationship of this variability to host plant preference must be investigated in an agricultural ecosystem.
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