156 research outputs found

    SYSTEM IMPEDANCYJNEJ TOMOGRAFII KOMPUTEROWEJ BAZUJĄCY NA PROCESORZE SYGNAŁOWYM O NISKIM POBORZE MOCY

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    Article contains description of the measurement system electrical impedance tomography solutions based on digital signal processor with low power consumption.Artykuł zawiera opis rozwiązania systemu pomiarowego tomografii impedancyjnej bazującego na procesorze sygnałowym o niskim poborze mocy

    Kimmeridgian hardground-sequence boundary from the Mesozoic margin of the Holy Cross Mountains (central Poland): implications for the evolution of the northern Tethyan carbonate shelf

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    The sedimentary succession in central Poland records significant changes in facies at the turn of the Planula and Platynota zones in the Upper Jurassic, expressed by the drowning of the ramp-type platform and development of an extensive isochronous marl horizon. The topmost level of the marl horizon is a regional hardground, which is interpreted as the third-order sequence boundary Kim 1. In some areas, the hardground was eroded and is only preserved as bored and encrusted clasts. The composition of the borings may indicate that colonization and recolonization of the clasts took place in an extremely shallow water environment. The overall low level diversity of clast-encrusting organisms and their occurrence on both sides of clasts indicates frequent overturning and high current activity. However, other extrinsic factors, such as salinity fluctuations, may have been involved. The final redeposition and burial of the clasts were related to subsidence through widespread reactivation of Paleozoic faults. Comparison with Middle Oxfordian–Lower Kimmeridgian sequences of central and southern Poland indicates that the carbonate ramp morphology and paleoenvironmental conditions were periodically subjected to significant modification during phases of extensional tectonics, with the development of fault-controlled intra-platform ridges and basins. These features may have been the NE continuation of parallel swells and basins developed in the southern part of the carbonate platform adjacent to the Tethys

    SYSTEM AKWIZYCJI DANYCH W ELEKTRYCZNEJ TOMOGRAFII IMPEDANCYJNEJ

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    This article presents the design of the device with active electrodes to examine the flood embankment. There was discussed the method of determining the conductivity. The presented solution was based on electrical impedance tomography. There was described the concept of active electrodes and measuring equipment for data acquisition. Electrical impedance tomography, which is based on measuring potential difference, can be used to calculate conductivity. The problem depends on the fact that every material has unique conductance.W tym artykule przedstawiono konstrukcję urządzenia z aktywnymi elektrodami do badania stanu wału przeciwpowodziowego. Omówiono metodę wyznaczania konduktywności. Prezentowane rozwiązanie zostało oparte na elektrycznej tomografii impedancyjnej. Opisano koncepcję aktywnych elektrod i sprzętu pomiarowego do akwizycji danych. Elektryczna tomografia impedancyjna, która jest oparta na pomiarze różnicy potencjałów może być użyta do pomiaru konduktywności. Sposób, w jaki może być zdefiniowany polega na tym, że każdy materiał ma unikalną przewodność

    Distance of the cervical part of the internal carotid artery from the selected anatomical structures in the parapharyngeal space and its relation to patient characteristics

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    Anomalies of the internal carotid artery (ICA) can increase the risk of haemorrhage during common surgical procedures. The aim of this literature review was to summarize the current state of knowledge on the course of the internal carotid artery in the parapharyngeal space, including the impact of the patient characteristics on the distances between the artery and other anatomical structures, as well as symptoms accompanying the aberrations. Pathologies related to the course of ICA in the parapharyngeal space are common (10%-60% in the general population and up to 84.4% in the elderly). In women, the distances in the oropharynx area are shorter than in men. Although the number of morphological studies is growing, providing more information on this topic, the identified studies differ in the methods and results. Knowledge on the variability in the course of ICA can help identify patients at high risk for the ICA trauma during pharyngeal procedures

    Iatrogenic hemobilia in 10-year-old boy

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    Background: Hemobilia in children is a rare phenomenon which has been described mostly in the context of traumas. The descriptions of massive hemobilia in children after liver biopsy are a rarity in the scientific literature because there are only a few examples of it. Hemobilia rarely develops spontaneously. Generally, this is a complication after a blunt abdominal trauma or after medical (especially surgical) procedures. Correct diagnosis and treatment of hemobilia are essential, especially in the case of patients with severe - sometimes life-threatening - haemorrhage from biliary ducts. It should be remembered that the symptoms of hemobilia do not necessarily occur immediately after surgery or trauma. In some cases hemobilia occurs after a changeable, asymptomatic period of time. Case Report: We would like to present a case of a severe form of hemobilia caused by arterio-biliary fistula which developed incidentally after liver biopsy in a 10-year-old boy with chronic hepatitis B. Symptoms of hemobilia appeared on the seventh day after the diagnostic biopsy when the patient’s general condition began to deteriorate. The diagnosis of arterio-biliary fistula was established after angio-CT examination of the liver. A selective embolization of the right hepatic artery was carried out. Hemobilia in children is a rare phenomenon which has been described mostly in the context of traumas. The cases of massive hemobilia in children after liver biopsy are a rarity in the scientific literature because there are only a few examples of it. Hemobilia very rarely develops spontaneously. Generally, this is a complication after a blunt abdominal trauma or after medical (especially surgical) procedures. Conclusions: Correct diagnosis and treatment of hemobilia are essential, especially in the case of patients with severe - sometimes life-threatening - haemorrhage from biliary ducts. It should be remembered that the symptoms of hemobilia do not necessarily occur immediately after surgery or trauma. In some cases hemobilia occurs after a changeable, asymptomatic period of time

    A Novel Cold-Adapted Lipase from Sorangium cellulosum Strain So0157-2: Gene Cloning, Expression, and Enzymatic Characterization

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    Genome sequencing of cellulolytic myxobacterium Sorangium cellulosum reveals many open-reading frames (ORFs) encoding various degradation enzymes with low sequence similarity to those reported, but none of them has been characterized. In this paper, a predicted lipase gene (lipA) was cloned from S. cellulosum strain So0157-2 and characterized. lipA is 981-bp in size, encoding a polypeptide of 326 amino acids that contains the pentapeptide (GHSMG) and catalytic triad residues (Ser114, Asp250 and His284). Searching in the GenBank database shows that the LipA protein has only the 30% maximal identity to a human monoglyceride lipase. The novel lipA gene was expressed in Escherichia coli BL21 and the recombinant protein (r-LipA) was purified using Ni-NTA affinity chromatography. The enzyme hydrolyzed the p-nitrophenyl (pNP) esters of short or medium chain fatty acids (≤C10), and the maximal activity was on pNP acetate. The r- LipA is a cold-adapted lipase, with high enzymatic activity in a wide range of temperature and pH values. At 4 °C and 30 °C, the Km values of r-LipA on pNP acetate are 0.037 ± 0.001 and 0.174 ± 0.006 mM, respectively. Higher pH and temperature conditions promoted hydrolytic activity toward the pNP esters with longer chain fatty acids. Remarkably, this lipase retained much of its activity in the presence of commercial detergents and organic solvents. The results suggest that the r-LipA protein has some new characteristics potentially promising for industrial applications and S. cellulosum is an intriguing resource for lipase screening

    Long range molecular dynamics study of regulation of eukaryotic glucosamine-6-phosphate synthase activity by UDP-GlcNAc

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    Glucosamine-6-phosphate (GlcN-6-P) synthase catalyses the first and practically irreversible step in hexosamine metabolism. The final product of this pathway, uridine 5’ diphospho N-acetyl-D-glucosamine (UDP-GlcNAc), is an essential substrate for assembly of bacterial and fungal cell walls. Moreover, the enzyme is involved in phenomenon of hexosamine induced insulin resistance in type II diabetes, which makes it a potential target for antifungal, antibacterial and antidiabetic therapy. The crystal structure of the isomerase domain of GlcN-6-P synthase from human pathogenic fungus Candida albicans, in complex with UDP-GlcNAc has been solved recently but it has not revealed the molecular mechanism of inhibition taking place under UDP-GlcNAc influence, the unique feature of the eukaryotic enzyme. UDP-GlcNAc is a physiological inhibitor of GlcN-6-P synthase, binding about 1 nm away from the active site of the enzyme. In the present work, comparative molecular dynamics simulations of the free and UDP-GlcNAc-bounded structures of GlcN-6-P synthase have been performed. The aim was to complete static X-ray structural data and detect possible changes in the dynamics of the two structures. Results of the simulation studies demonstrated higher mobility of the free structure when compared to the liganded one. Several amino acid residues were identified, flexibility of which is strongly affected upon UDP-GlcNAc binding. Importantly, the most fixed residues are those related to the inhibitor binding process and to the catalytic reaction. The obtained results constitute an important step toward understanding of mechanism of GlcN-6-P synthase inhibition by UDP-GlcNAc molecule

    Added value of diffusion-weighted images and dynamic contrast enhancement in multiparametric magnetic resonance imaging for the detection of clinically significant prostate cancer in the PICTURE trial

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    Objective To determine the additional diagnostic value of diffusion‐weighted imaging (DWI) and dynamic contrast‐enhanced (DCE) imaging in men requiring a repeat biopsy within the PICTURE study. Patients and Methods PICTURE was a paired‐cohort confirmatory study in which 249 men who required further risk stratification following a previous non‐MRI guided TRUS biopsy underwent a 3‐Tesla mpMRI consisting of T2W, DWI and DCE followed by transperineal template prostate mapping (TPM) biopsy. Each mpMRI was reported using a LIKERT score in a sequential blinded manner to generate scores for T2W, T2W+DWI and T2W+DWI+DCE. Area under the receiver operating characteristic (AUROC) fanalysis was performed to compare the diagnostic accuracy of each combination. The threshold for a positive mpMRI was set as a LIKERT score >/=3. Clinically significant prostate cancer was analysed across a range of definitions including UCL/Ahmed Definition 1 (primary definition), UCL/Ahmed Definition 2, any Gleason >/=3+4 and any Gleason >/=4+3. Results Of 249, sequential MRI reporting was available for 246. There was a higher rate of equivocal lesions (44.6%) using T2W alone compared to the addition of DWI (23.9%) and DCE (19.8%). Using the primary definition of clinically significant disease, there was no significant difference in the overall accuracy between T2W at AUROC 0.74 (95% CI 0.68‐0.80), T2W+DWI at 0.76 (95% CI 0.71‐0.82) and T2W+DWI+DCE at 0.77 (95% CI 0.71‐0.82) (p=0.55). The AUROCs remained comparable using other definitions of clinically significant disease including UCL/Ahmed 2 (p=0.79), Gleason >/=3+4 (p=0.53) and Gleason >/=4+3 (p=0.53). Conclusions Using a 3T MRI, a high level of diagnostic accuracy can be achieved using T2W as a single parameter in men with a prior biopsy. However, such a strategy can lead to a higher rate of equivocal lesions
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