Análisis in vivo de la vasculopatía arterial pulmonar mediante ultrasonido intravascular (IVUS) en pacientes con insuficiencia respiratoria crónica evaluados para trasplante pulmonar

El objetivo del estudio es evaluar el remodelado estructural y funcional de las arterias pulmonares asociado a insuficiencia respiratoria crónica severa, mediante ecografía intravascular (IVUS). Se incluyeron 80 pacientes en estudio pretrasplante pulmonar a los que se les realizó cateterismo cardiaco derecho e IVUS de una arteria pulmonar de mediano calibre. A través del IVUS se determinó el módulo elástico, pulsatilidad y porcentaje de fibrosis arterial. La insuficiencia respiratoria crónica se asoció a una vasculopatía arterial pulmonar severa, independientemente de la presencia de hipertensión pulmonar. Los pacientes con EPOC (enfermedad pulmonar obstructiva crónica) presentaban un mayor grado de fibrosis arterial, mientras que los pacientes con EPID (enfermedad pulmonar intersticial difusa) presentaban mayor rigidez arterial.

Global Genomic Diversity of Human Papillomavirus 6 Based on 724 Isolates and 190 Complete Genome Sequences.

Human papillomavirus type 6 (HPV6) is the major etiological agent of anogenital warts and laryngeal papillomas and has been included in both the quadrivalent and nonavalent prophylactic HPV vaccines. This study investigated the global genomic diversity of HPV6, using 724 isolates and 190 complete genomes from six continents, and the association of HPV6 genomic variants with geographical location, anatomical site of infection/disease, and gender. Initially, a 2,800-bp E5a-E5b-L1-LCR fragment was sequenced from 492/530 (92.8%) HPV6-positive samples collected for this study. Among them, 130 exhibited at least one single nucleotide polymorphism (SNP), indel, or amino acid change in the E5a-E5b-L1-LCR fragment and were sequenced in full. A global alignment and maximum likelihood tree of 190 complete HPV6 genomes (130 fully sequenced in this study and 60 obtained from sequence repositories) revealed two variant lineages, A and B, and five B sublineages: B1, B2, B3, B4, and B5. HPV6 (sub)lineage-specific SNPs and a 960-bp representative region for whole-genome-based phylogenetic clustering within the L2 open reading frame were identified. Multivariate logistic regression analysis revealed that lineage B predominated globally. Sublineage B3 was more common in Africa and North and South America, and lineage A was more common in Asia. Sublineages B1 and B3 were associated with anogenital infections, indicating a potential lesion-specific predilection of some HPV6 sublineages. Females had higher odds for infection with sublineage B3 than males. In conclusion, a global HPV6 phylogenetic analysis revealed the existence of two variant lineages and five sublineages, showing some degree of ethnogeographic, gender, and/or disease predilection in their distribution. IMPORTANCE: This study established the largest database of globally circulating HPV6 genomic variants and contributed a total of 130 new, complete HPV6 genome sequences to available sequence repositories. Two HPV6 variant lineages and five sublineages were identified and showed some degree of association with geographical location, anatomical site of infection/disease, and/or gender. We additionally identified several HPV6 lineage- and sublineage-specific SNPs to facilitate the identification of HPV6 variants and determined a representative region within the L2 gene that is suitable for HPV6 whole-genome-based phylogenetic analysis. This study complements and significantly expands the current knowledge of HPV6 genetic diversity and forms a comprehensive basis for future epidemiological, evolutionary, functional, pathogenicity, vaccination, and molecular assay development studies.

André spectral sequences for Baues-Wirsching cohomology of categories

We construct spectral sequences in the framework of Baues-Wirsching cohomology and homology for functors between small categories and analyze particular cases including Grothendieck fibrations. We also give applications to more classical cohomology and homology theories including Hochschild-Mitchell cohomology and those studied before by Watts, Roos, Quillen and others

Localized in vivo hyperpolarization transfer sequences.

In vivo localized and fully adiabatic homonuclear and heteronuclear polarization transfer experiments were designed and performed in the rat brain at 9.4 T after infusion of hyperpolarized sodium [1,2-(13)C(2)] and sodium [1-(13)C] acetate. The method presented herein leads to highly enhanced in vivo detection of short-T(1) (13)C as well as attached protons. This indirect detection scheme allows for probing additional molecular sites in hyperpolarized substrates and their metabolites and can thus lead to improved spectral resolution such as in the case of (13)C-acetate metabolism.

Model-based Segmentation and Fusion of 3D Computed Tomography and 3D Ultrasound of the Eye for Radiotherapy Planning

Computed Tomography (CT) represents the standard imaging modality for tumor volume delineation for radiotherapy treatment planning of retinoblastoma despite some inherent limitations. CT scan is very useful in providing information on physical density for dose calculation and morphological volumetric information but presents a low sensitivity in assessing the tumor viability. On the other hand, 3D ultrasound (US) allows a highly accurate definition of the tumor volume thanks to its high spatial resolution but it is not currently integrated in the treatment planning but used only for diagnosis and follow-up. Our ultimate goal is an automatic segmentation of gross tumor volume (GTV) in the 3D US, the segmentation of the organs at risk (OAR) in the CT and the registration of both modalities. In this paper, we present some preliminary results in this direction. We present 3D active contour-based segmentation of the eye ball and the lens in CT images; the presented approach incorporates the prior knowledge of the anatomy by using a 3D geometrical eye model. The automated segmentation results are validated by comparing with manual segmentations. Then, we present two approaches for the fusion of 3D CT and US images: (i) landmark-based transformation, and (ii) object-based transformation that makes use of eye ball contour information on CT and US images.

Ultrasound assessment of ocular vascular effects of repeated intravitreal injections of ranibizumab for wet age-related macular degeneration.

PURPOSE: Determine the effect of repeated intravitreal injections of ranibizumab (0.5 mg; 0.05 ml) on retrobulbar blood flow velocities (BFVs) using ultrasound imaging quantification in twenty patients with exudative age-related macular degeneration treated for 6 months. METHODS: Visual acuity (ETDRS), central macular thickness (OCT), peak-systolic, end-diastolic and mean-BFVs in central retinal (CRA), temporal posterior ciliary (TPCA) and ophthalmic (OA) arteries were measured before, 2 days, 3 weeks and 6 months after the first injection. Patients were examined monthly and received 1-5 additional injections depending on ophthalmologic examination results. RESULTS: Six months after the first injection, a significant increase in visual acuity 50.9 ± 25.9 versus 44.4 ± 21.7 (p < 0.01) and decrease in mean central macular thickness 267 ± 74 versus 377 ± 115 μm (p < 0.001) were observed compared to baseline. Although mean-BFVs decreased by 16%±3% in CRA and 20%±5% in TPCA (p < 0.001) 2 days after the first injection, no significant change was seen thereafter. Mean-BFVs in OA decreased by 19%±5% at week 3 (p < 0.001). However, the smallest number of injections (two injections) was associated with the longest time interval between the last injection and month 6 (20 weeks) and with the best return to baseline levels for mean-BFVs in CRA, suggesting that ranibizumab had reversible effects on native retinal vascular supply after its discontinuation. Moreover, a significant correlation between the number of injections and percentage of changes in mean-BFVs in CRA was observed at month 6 (R = 0.74, p < 0.001) unlike TPCA or OA. CONCLUSION: Ranibizumab could impair the native choroidal and retinal vascular networks, but its effect seems reversible after its discontinuation.

Temporal and spatial origin of Gesneriaceae in the New World inferred from plastid DNA sequences

Gesneriaceae are represented in the New World (NW) by a major clade (c. 1000 species) currently recognized as subfamily Gesnerioideae. Radiation of this group occurred in all biomes of tropical America and was accompanied by extensive phenotypic and ecological diversification. Here we performed phylogenetic analyses using DNA sequences from three plastid loci to reconstruct the evolutionary history of Gesnerioideae and to investigate its relationship with other lineages of Gesneriaceae and Lamiales. Our molecular data confirm the inclusion of the South Pacific Coronanthereae and the Old World (OW) monotypic genus Titanotrichum in Gesnerioideae and the sister-group relationship of this subfamily to the rest of the OW Gesneriaceae. Calceolariaceae and the NW genera Peltanthera and Sanango appeared successively sister to Gesneriaceae, whereas Cubitanthus, which has been previously assigned to Gesneriaceae, is shown to be related to Linderniaceae. Based on molecular dating and biogeographical reconstruction analyses, we suggest that ancestors of Gesneriaceae originated in South America during the Late Cretaceous. Distribution of Gesneriaceae in the Palaeotropics and Australasia was inferred as resulting from two independent long-distance dispersals during the Eocene and Oligocene, respectively. In a short time span starting at 34 Mya, ancestors of Gesnerioideae colonized several Neotropical regions including the tropical Andes, Brazilian Atlantic forest, cerrado, Central America and the West Indies. Subsequent diversification within these areas occurred largely in situ and was particularly extensive in the mountainous systems of the Andes, Central America and the Brazilian Atlantic forest. Only two radiations account for 90% of the diversity of Gesneriaceae in the Brazilian Atlantic forest, whereas half of the species richness in the northern Andes and Central America originated during the last 10 Myr from a single radiation.

An Efficient Segmentation Method for Ultrasound Images based on a Semi-supervised Approach and Patch-based Features

Segmenting ultrasound images is a challenging problemwhere standard unsupervised segmentation methods such asthe well-known Chan-Vese method fail. We propose in thispaper an efficient segmentation method for this class ofimages. Our proposed algorithm is based on asemi-supervised approach (user labels) and the use ofimage patches as data features. We also consider thePearson distance between patches, which has been shown tobe robust w.r.t speckle noise present in ultrasoundimages. Our results on phantom and clinical data show avery high similarity agreement with the ground truthprovided by a medical expert.

Thalamic connectivity in patients with essential tremor treated with MR imaging-guided focused ultrasound: in vivo fiber tracking by using diffusion-tensor MR imaging.

PURPOSE: To use diffusion-tensor (DT) magnetic resonance (MR) imaging in patients with essential tremor who were treated with transcranial MR imaging-guided focused ultrasound lesion inducement to identify the structural connectivity of the ventralis intermedius nucleus of the thalamus and determine how DT imaging changes correlated with tremor changes after lesion inducement. MATERIALS AND METHODS: With institutional review board approval, and with prospective informed consent, 15 patients with medication-refractory essential tremor were enrolled in a HIPAA-compliant pilot study and were treated with transcranial MR imaging-guided focused ultrasound surgery targeting the ventralis intermedius nucleus of the thalamus contralateral to their dominant hand. Fourteen patients were ultimately included. DT MR imaging studies at 3.0 T were performed preoperatively and 24 hours, 1 week, 1 month, and 3 months after the procedure. Fractional anisotropy (FA) maps were calculated from the DT imaging data sets for all time points in all patients. Voxels where FA consistently decreased over time were identified, and FA change in these voxels was correlated with clinical changes in tremor over the same period by using Pearson correlation. RESULTS: Ipsilateral brain structures that showed prespecified negative correlation values of FA over time of -0.5 or less included the pre- and postcentral subcortical white matter in the hand knob area; the region of the corticospinal tract in the centrum semiovale, in the posterior limb of the internal capsule, and in the cerebral peduncle; the thalamus; the region of the red nucleus; the location of the central tegmental tract; and the region of the inferior olive. The contralateral middle cerebellar peduncle and bilateral portions of the superior vermis also showed persistent decrease in FA over time. There was strong correlation between decrease in FA and clinical improvement in hand tremor 3 months after lesion inducement (P < .001). CONCLUSION: DT MR imaging after MR imaging-guided focused ultrasound thalamotomy depicts changes in specific brain structures. The magnitude of the DT imaging changes after thalamic lesion inducement correlates with the degree of clinical improvement in essential tremor.

Crop sequences in no-tillage system: effects on soil fertility and soybean, maize and rice yield

Decomposing crop residues in no-tillage system can alter soil chemical properties, which may consequently influence the productivity of succession crops. The objective of this study was to evaluate soil chemical properties and soybean, maize and rice yield, grown in the summer, after winter crops in a no-tillage system. The experiment was carried out in Jaboticabal, SP, Brazil (21 ° 15 ' 22 '' S; 48 ° 18 ' 58 '' W) on a Red Latosol (Oxisol), in a completely randomized block design, in strip plots with three replications. The treatments consisted of four summer crop sequences (maize monocrop, soybean monocrop, soybean/maize rotation and rice/bean/cotton rotation) combined with seven winter crops (maize, sunflower, oilseed radish, pearl millet, pigeon pea, grain sorghum and sunn hemp). The experiment began in September 2002. After the winter crops in the 2005/2006 growing season and before the sowing of summer crops in the 2006/2007 season, soil samples were collected in the layers 0-2.5; 2.5-5.0; 5-10; 10-20; and 20-30 cm. Organic matter, pH, P, K+, Ca2+, Mg2+, and H + Al were determined in each soil sample. In the summer soybean/maize rotation and in maize the organic matter contents and P levels were lower, in the layers 0-10 cm and 0-20 cm, respectively. Summer rice/bean/cotton rotation increased soil K levels at 0-10 cm depth when sunn hemp and oilseed radish had previously been grown in the winter, and in the 0-2.5 cm layer for millet. Sunn hemp, millet, oilseed radish and sorghum grown in the winter increased organic matter contents in the soil down to 30 cm. Higher P levels were found at the depths 0-2.5 cm and 0-5 cm, respectively, when sunn hemp and oilseed radish were grown in the winter. Highest grain yields for soybean in monoculture were obtained in succession to winter oilseed radish and sunn hemp and in rotation with maize, after oilseed radish, sunn hemp and millet. Maize yields were highest in succession to winter oilseed radish, millet and pigeon pea. Rice yields were lowest when grown after sorghum.

Evaluation of prenatal diagnosis of congenital heart diseases by ultrasound: experience from 20 European registries.

OBJECTIVES: To evaluate prenatal diagnosis of congenital heart diseases by ultrasound investigation in well-defined European populations. DESIGN: Data from 20 registries of congenital malformations in 12 European countries were included. The prenatal ultrasound screening programs in the countries ranged from no routine screening to three ultrasound investigations per patient routinely performed. RESULTS: There were 2454 cases with congenital heart disease with an overall prenatal detection rate of 25%. Termination of pregnancy was performed in 293 cases (12%). There was considerable variation in prenatal detection rate between regions, with the lowest detection rates being in countries without ultrasound screening (11%) and in Eastern European countries (Croatia, Lithuania and Ukraine; 8%). In Western European countries with ultrasound screening, detection rate ranged from 19-48%. There was a significant difference in prenatal detection rate and proportion of induced abortions between isolated congenital heart disease and congenital heart disease associated with chromosome anomalies, multiple malformations and syndromes (P < 0.0001). There were 1694 cases with isolated congenital heart disease of which 16% were diagnosed prenatally. Malformations affecting the size of the ventricles were detected prenatally in half of the cases. CONCLUSIONS: Prenatal detection rate of congenital heart disease varies significantly between countries even with the same screening recommendations. The presence of associated malformations significantly increases the prenatal detection rate.