62 resultados para Simultaneous Localization and Mapping


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AIM: The aim of this study was to compare the clinical outcomes after 2 years with bone level implants placed to restore a single missing teeth that needed simultaneous augmentation and were treated with a transmucosal or submerged approach. METHODS: This study analyzed a subset of patients included in an ongoing prospective multicenter randomized clinical trial (RCT) involving12 centers where patients were to be followed-up to 5 years after loading. Of the 120 implants that were placed in the original study, and randomly assigned to submerged or non-submerged healing, 52 needed simultaneous augmentation (28 women patients and 24 men patients, between 23 and 78 years of age). Twenty-seven of them received implants with submerged healing (AuS), while in 25 patients the implants were inserted with a non-submerged protocol (AuNS). At the 2-year follow-up visit, radiographic crestal bone level changes were recorded as well as soft tissue parameters included Pocket probing depth (PPD), bleeding on probing (BoP) and clinical attachment level (CAL) at teeth adjacent to the implant site. RESULTS: After 2 years a small amount of bone resorption was found in both groups (0.37 ± 0.49 mm in the AuS group and 0.54 ± 0.76 in the AuNS group; P < 0.001). There was no statistically significant difference between AuS Group and AuNS group for PPD (2.5 vs. 2.4 mm), BOP (BOP + sites: 8.8% vs. 11.5%) and CAL (2.8 vs. 2.4 mm) at the 2-year follow-up visit. CONCLUSIONS: When a single implant is placed in the aesthetic zone in conjunction with bone augmentation for a moderate peri-implant defect, submerged and transmucosal healing determine similar outcome, hence there is no need to submerge an implant in this given clinical situation.

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Cyclic nucleotide specific phosphodiesterases (PDEs) are pivotal regulators of cellular signaling. They are also important drug targets. Besides catalytic activity and substrate specificity, their subcellular localization and interaction with other cell components are also functionally important. In contrast to the mammalian PDEs, the significance of PDEs in protozoal pathogens remains mostly unknown. The genome of Trypanosoma brucei, the causative agent of human sleeping sickness, codes for five different PDEs. Two of these, TbrPDEB1 and TbrPDEB2, are closely similar, cAMP-specific PDEs containing two GAF-domains in their N-terminal regions. Despite their similarity, these two PDEs exhibit different subcellular localizations. TbrPDEB1 is located in the flagellum, whereas TbrPDEB2 is distributed between flagellum and cytoplasm. RNAi against the two mRNAs revealed that the two enzymes can complement each other but that a simultaneous ablation of both leads to cell death in bloodstream form trypanosomes. RNAi against TbrPDEB1 and TbrPDEB2 also functions in vivo where it completely prevents infection and eliminates ongoing infections. Our data demonstrate that TbrPDEB1 and TbrPDEB2 are essential for virulence, making them valuable potential targets for new PDE-inhibitor based trypanocidal drugs. Furthermore, they are compatible with the notion that the flagellum of T. brucei is an important site of cAMP signaling.--Oberholzer, M., Marti, G., Baresic, M., Kunz, S., Hemphill, A., Seebeck, T. The Trypanosoma brucei cAMP phosphodiesterases TbrPDEB1 and TbrPDEB2: flagellar enzymes that are essential for parasite virulence.

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Cognitive functions in the child's brain develop in the context of complex adaptive processes, determined by genetic and environmental factors. Little is known about the cerebral representation of cognitive functions during development. In particular, knowledge about the development of right hemispheric (RH) functions is scarce. Considering the dynamics of brain development, localization and lateralization of cognitive functions must be expected to change with age. Twenty healthy subjects (8.6-20.5 years) were examined with fMRI and neuropsychological tests. All participants completed two fMRI tasks known to activate left hemispheric (LH) regions (language tasks) and two tasks known to involve predominantly RH areas (visual search tasks). A laterality index (LI) was computed to determine the asymmetry of activation. Group analysis revealed unilateral activation of the LH language circuitry during language tasks while visual search tasks induced a more widespread RH activation pattern in frontal, superior temporal, and occipital areas. Laterality of language increased between the ages of 8-20 in frontal (r = 0.392, P = 0.049) and temporal (r = 0.387, P = 0.051) areas. The asymmetry of visual search functions increased in frontal (r = -0.525, P = 0.009) and parietal (r = -0.439, P = 0.027) regions. A positive correlation was found between Verbal-IQ and the LI during a language task (r = 0.585, P = 0.028), while visuospatial skills correlated with LIs of visual search (r = -0.621, P = 0.018). To summarize, cognitive development is accompanied by changes in the functional representation of neuronal circuitries, with a strengthening of lateralization not only for LH but also for RH functions. Our data show that age and performance, independently, account for the increases of laterality with age.

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Campylobacter spp., Salmonella enterica, and Yersinia enterocolitica are common causes of foodborne infections in humans with pork as a potential source. Monitoring programs at farm level are, to date, only implemented for S. enterica, while epidemiological knowledge of the other two pathogens is still lacking. This study aimed to assess the pathogen load (in the pigs' environment) in fattening pig herds, their simultaneous occurrence, and the occurrence of Campylobacter spp. and Y. enterocolitica in herds in different Salmonella risk categories. In 50 fattening pig herds in northern Germany, four pooled fecal samples and 10 swab samples from the pigs' direct environment (pen walls, nipple drinkers), indirect environment (hallways, drive boards), and flies and rodent droppings were collected from each herd and submitted for cultural examination. Campylobacter spp. were detected in 38.1% of fecal, 32.7% of direct environment, 5.3% of indirect environment, and 4.6% of flies/pests samples collected, and Y. enterocolitica in 17.1, 8.1, 1.2, and 3.1% and S. enterica in 11.2, 7.7, 4.1, and 1.5%, respectively. For Campylobacter spp., Y. enterocolitica, and S. enterica, 80, 48, and 32% of herds were positive, respectively; 22 herds were positive for both Campylobacter spp. and Y. enterocolitica, 12 for Campylobacter spp. and S. enterica, and 7 for Y. enterocolitica and S. enterica. There was no significant association between the pathogens at herd level. Campylobacter spp. and Y. enterocolitica were found more often in samples from the low Salmonella risk category (odds ratio, 0.51; confidence interval, 0.36 to 0.73, and 0.3, 0.17 to 0.57), and this was also the case for Y. enterocolitica at herd level (odds ratio, 0.08; confidence interval, 0.02 to 0.3). This study provides evidence that the pigs' environment should be accounted for when implementing control measures on farms against Campylobacter spp. and Y. enterocolitica. An extrapolation from the current Salmonella monitoring to the other two pathogens does not seem feasible.

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An efficient and reliable automated model that can map physical Soil and Water Conservation (SWC) structures on cultivated land was developed using very high spatial resolution imagery obtained from Google Earth and ArcGIS, ERDAS IMAGINE, and SDC Morphology Toolbox for MATLAB and statistical techniques. The model was developed using the following procedures: (1) a high-pass spatial filter algorithm was applied to detect linear features, (2) morphological processing was used to remove unwanted linear features, (3) the raster format was vectorized, (4) the vectorized linear features were split per hectare (ha) and each line was then classified according to its compass direction, and (5) the sum of all vector lengths per class of direction per ha was calculated. Finally, the direction class with the greatest length was selected from each ha to predict the physical SWC structures. The model was calibrated and validated on the Ethiopian Highlands. The model correctly mapped 80% of the existing structures. The developed model was then tested at different sites with different topography. The results show that the developed model is feasible for automated mapping of physical SWC structures. Therefore, the model is useful for predicting and mapping physical SWC structures areas across diverse areas.

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The cardiac voltage-gated Na(+) channel Na(v)1.5 generates the cardiac Na(+) current (INa). Mutations in SCN5A, the gene encoding Na(v)1.5, have been linked to many cardiac phenotypes, including the congenital and acquired long QT syndrome, Brugada syndrome, conduction slowing, sick sinus syndrome, atrial fibrillation, and dilated cardiomyopathy. The mutations in SCN5A define a sub-group of Na(v)1.5/SCN5A-related phenotypes among cardiac genetic channelopathies. Several research groups have proposed that Na(v)1.5 may be part of multi-protein complexes composed of Na(v)1.5-interacting proteins which regulate channel expression and function. The genes encoding these regulatory proteins have also been found to be mutated in patients with inherited forms of cardiac arrhythmias. The proteins that associate with Na(v)1.5 may be classified as (1) anchoring/adaptor proteins, (2) enzymes interacting with and modifying the channel, and (3) proteins modulating the biophysical properties of Na(v)1.5 upon binding. The aim of this article is to review these Na(v)1.5 partner proteins and to discuss how they may regulate the channel's biology and function. These recent investigations have revealed that the expression level, cellular localization, and activity of Na(v)1.5 are finely regulated by complex molecular and cellular mechanisms that we are only beginning to understand.

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To elucidate the local formation of angiotensin II (Ang II) in the neurons of sensory dorsal root ganglia (DRG), we studied the expression of angiotensinogen (Ang-N)-, renin-, angiotensin converting enzyme (ACE)- and cathepsin D-mRNA, and the presence of protein renin, Ang II, Substance P and calcitonin gene-related peptide (CGRP) in the rat and human thoracic DRG. Quantitative real time PCR (qRT-PCR) studies revealed that rat DRG expressed substantial amounts of Ang-N- and ACE mRNA, while renin mRNA as well as the protein renin were untraceable. Cathepsin D-mRNA and cathepsin D-protein were detected in the rat DRG indicating the possibility of existence of pathways alternative to renin for Ang I formation. Angiotensin peptides were successfully detected with high performance liquid chromatography and radioimmunoassay in human DRG extracts. In situ hybridization in rat DRG confirmed additionally expression of Ang-N mRNA in the cytoplasm of numerous neurons. Intracellular Ang II staining could be shown in number of neurons and their processes in both the rat and human DRG. Interestingly we observed neuronal processes with angiotensinergic synapses en passant, colocalized with synaptophysin, within the DRG. In the DRG, we also identified by qRT-PCR, expression of Ang II receptor AT(1A) and AT(2)-mRNA while AT(1B)-mRNA was not traceable. In some neurons Substance P and CGRP were found colocalized with Ang II. The intracellular localization and colocalization of Ang II with Substance P and CGRP in the DRG neurons may indicate a participation and function of Ang II in the regulation of nociception. In conclusion, these results suggest that Ang II may be produced locally in the neurons of rat and human DRG and act as a neurotransmitter.

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The multi-target screening method described in this work allows the simultaneous detection and identification of 700 drugs and metabolites in biological fluids using a hybrid triple-quadrupole linear ion trap mass spectrometer in a single analytical run. After standardization of the method, the retention times of 700 compounds were determined and transitions for each compound were selected by a "scheduled" survey MRM scan, followed by an information-dependent acquisition using the sensitive enhanced product ion scan of a Q TRAP hybrid instrument. The identification of the compounds in the samples analyzed was accomplished by searching the tandem mass spectrometry (MS/MS) spectra against the library we developed, which contains electrospray ionization-MS/MS spectra of over 1,250 compounds. The multi-target screening method together with the library was included in a software program for routine screening and quantitation to achieve automated acquisition and library searching. With the help of this software application, the time for evaluation and interpretation of the results could be drastically reduced. This new multi-target screening method has been successfully applied for the analysis of postmortem and traffic offense samples as well as proficiency testing, and complements screening with immunoassays, gas chromatography-mass spectrometry, and liquid chromatography-diode-array detection. Other possible applications are analysis in clinical toxicology (for intoxication cases), in psychiatry (antidepressants and other psychoactive drugs), and in forensic toxicology (drugs and driving, workplace drug testing, oral fluid analysis, drug-facilitated sexual assault).

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Aldosterone and corticosterone bind to mineralocorticoid (MR) and glucocorticoid receptors (GR), which, upon ligand binding, are thought to translocate to the cell nucleus to act as transcription factors. Mineralocorticoid selectivity is achieved by the 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) that inactivates 11β-hydroxy glucocorticoids. High expression levels of 11β-HSD2 characterize the aldosterone-sensitive distal nephron (ASDN), which comprises the segment-specific cells of late distal convoluted tubule (DCT2), connecting tubule (CNT), and collecting duct (CD). We used MR- and GR-specific antibodies to study localization and regulation of MR and GR in kidneys of rats with altered plasma aldosterone and corticosterone levels. In control rats, MR and GR were found in cell nuclei of thick ascending limb (TAL), DCT, CNT, CD cells, and intercalated cells (IC). GR was also abundant in cell nuclei and the subapical compartment of proximal tubule (PT) cells. Dietary NaCl loading, which lowers plasma aldosterone, caused a selective removal of GR from cell nuclei of 11β-HSD2-positive ASDN. The nuclear localization of MR was unaffected. Adrenalectomy (ADX) resulted in removal of MR and GR from the cell nuclei of all epithelial cells. Aldosterone replacement rapidly relocated the receptors in the cell nuclei. In ASDN cells, low-dose corticosterone replacement caused nuclear localization of MR, but not of GR. The GR was redistributed to the nucleus only in PT, TAL, early DCT, and IC that express no or very little 11β-HSD2. In ASDN cells, nuclear GR localization was only achieved when corticosterone was replaced at high doses. Thus ligand-induced nuclear translocation of MR and GR are part of MR and GR regulation in the kidney and show remarkable segment- and cell type-specific characteristics. Differential regulation of MR and GR may alter the level of heterodimerization of the receptors and hence may contribute to the complexity of corticosteroid effects on ASDN function.

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In humans, there are different types of cutaneous cold-sensitive afferents responsible for cold sensation and cold pain. Innocuous cold is primarily mediated by a population of slow A delta afferents, based on psychophysical and neurophysiological studies. Noxious cold (usually below 15 degrees C) is mediated, at least in part, by polymodal nociceptors. There is also a population of unmyelinated afferents responsive to innocuous low temperature, some of which also respond to heat, whose sensory function has not been completely defined. A paradoxical hot/burning evoked by cooling is unmasked by A-fibre block, and similar sensations are evoked by applying simultaneous cool and warm stimuli to adjacent skin areas. These unmyelinated fibres activated by innocuous cooling (and heating) may contribute to this hot/burning sensation, along with other thermoregulatory functions.

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Background The evaluation of the hepatic parenchyma in patients with chronic liver disease is important to assess the extension, localization and relationship with adjacent anatomical structures of possible lesions. This is usually performed with conventional abdominal ultrasound, CT-scan or magnetic resonance imaging. In this context, the feasibility and the safety of intravascular ultrasound in the liver have not been assessed yet. Methods We tested the safety and performance of an intracardiac echography (ICE) catheter applied by a transjugular approach into the hepatic veins in patients with chronic liver disease undergoing hepatic hemodynamic measurements. Results Five patients were enrolled in this pilot study. The insertion of the ICE catheter was possible into the right and middle, but not into the left hepatic vein. The position of the ICE was followed using fluoroscopy and external conventional ultrasound. Accurate imaging of focal hepatic parenchymal lesions, Doppler ultrasound of surrounding blood vessels and assessment of liver surface and ascites were achieved without complications. Conclusions This study demonstrated that a diagnostic approach using an ICE device inserted in the hepatic veins is feasible, safe and well tolerated. However, it remains for the moment only an experimental investigative tool. Whether ICE adds further information regarding parenchymal lesions and associated vascular alterations as compared to other techniques, needs additional investigation.

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Restriction of proteins to discrete subcellular regions is a common mechanism to establish cellular asymmetries and depends on a coordinated program of mRNA localization and translation control. Many processes from the budding of a yeast to the establishment of metazoan embryonic axes and the migration of human neurons, depend on this type of cell polarization. How factors controlling transport and translation assemble to regulate at the same time the movement and translation of transported mRNAs, and whether these mechanisms are conserved across kingdoms is not yet entirely understood. In this review we will focus on some of the best characterized examples of mRNA transport machineries, the "yeast locasome" as an example of RNA transport and translation control in unicellular eukaryotes, and on the Drosophila Bic-D/Egl/Dyn RNA localization machinery as an example of RNA transport in higher eukaryotes. This focus is motivated by the relatively advanced knowledge about the proteins that connect the localizing mRNAs to the transport motors and the many well studied proteins involved in translational control of specific transcripts that are moved by these machineries. We will also discuss whether the core of these RNA transport machineries and factors regulating mRNA localization and translation are conserved across eukaryotes.

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Lymph node involvement is prognostically the most determinant clinical factor for patients with head and neck squamous cell carcinomas (HNSCCs). Ultrasound of the neck and fine-needle aspiration (FNA) cytology is one of the first diagnostic procedures and the most accurate diagnostic staging tool for the neck. Patients with HPV-positive oropharyngeal carcinomas (OPSCC) show a significantly better prognosis when compared with HPV-negative OPSCC. P16 overexpression is accepted as surrogate marker for HPV-positive in OPSCC. These HPV/p16-positive OPSCC are localized either in the palatal tonsils or the base of tongue and frequently present with lymph node metastases. We analyzed the correlation and reliability of p16 expression of the FNA of the lymph node metastasis with the immunohistochemical expression of p16 of the same lymph node metastasis and its corresponding primary tumor, as it could be of importance for determining the localization and different prognosis of the primary tumor. 54 HNSCC patients were evaluated, p16 expression of the primary tumors and their lymph node metastases correlated precisely. In 25 of the 54 HNSCC patients, a FNA of the lymph node metastases was taken before the treatment. The positive cytological and immunohistochemical p16 staining correlated exactly. Of the 17 histologically p16-negative lymph node metastases 15 FNA were p16-negative, whereas two samples were p16-positive. In our view, a cytological p16 analysis of cervical lymph node metastasis can facilitate the correct localization of the primary tumor and discriminate reliably HPV-positive OPSCC from HPV-negative HNSCC with their significantly diverse prognosis.