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71.
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Kondzior Eliza Tokarska Małgorzata Kowalczyk Rafał Ruczyńska Iwona Sobociński Wojciech Kołodziej-Sobocińska Marta 《Parasitology research》2018,117(11):3659-3662
Parasitology Research - Sparganosis is a zoonosis caused by the spargana (larvae) of Spirometra sp. (Diphyllobothriidae). Reptiles are particularly important vectors for the transmission of this... 相似文献
73.
Andrzej Bożek Krzysztof Kołodziejczyk Jerzy Jarząb 《Annals of allergy, asthma & immunology》2018,120(1):53-58
Background
Local allergic rhinitis (LAR) is a relatively new disease.Objective
To ascertain the effects of allergen-specific immunotherapy in LAR.Methods
A randomized, double-blind, placebo-controlled trial of birch subcutaneous allergen immunotherapy (AIT) for LAR was performed in 28 patients. The therapy was performed for 24 months in 15 patients with AIT and 13 patients given placebo. The primary end point was decrease in symptom medication score (SMS). In addition, we monitored serum-specific immunoglobulin E (IgE), serum-specific immunoglobulin G4, nasal-specific IgE to Bet v 1, and safety and quality-of-life parameters.Results
After 24 months of treatment, there was a significant decrease in the median area under the curve for SMS of the active group vs the placebo group: 2.14 (range, 1.22–4.51) vs 6.21 (range, 5.12–7.89), at the P?<?.05 level. During AIT, the active group showed a significant decrease in SMS of up to 65% vs baseline. A significant increase in immunoglobulin G4 and decrease in nasal-specific IgE were observed in the active group during AIT compared with the placebo group. AIT was well-tolerated and without systemic reactions.Conclusion
This study demonstrates that AIT for birch pollen in patients with LAR was clinically effective and exhibited good tolerance.74.
Chang-Mo Nam Kyong Joon Lee Yousun Ko Kil Joong Kim Bohyoung Kim Kyoung Ho Lee 《BMC medical imaging》2018,18(1):53
Background
To develop an algorithm to predict the visually lossless thresholds (VLTs) of CT images solely using the original images by exploiting the image features and DICOM header information for JPEG2000 compression and to evaluate the algorithm in comparison with pre-existing image fidelity metrics.Methods
Five radiologists independently determined the VLT for 206 body CT images for JPEG2000 compression using QUEST procedure. The images were divided into training (n?=?103) and testing (n?=?103) sets. Using the training set, a multiple linear regression (MLR) model was constructed regarding the image features and DICOM header information as independent variables and regarding the VLTs determined with median value of the radiologists’ responses (VLTrad) as dependent variable, after determining an optimal subset of independent variables by backward stepwise selection in a cross-validation scheme.The performance was evaluated on the testing set by measuring absolute differences and intra-class correlation (ICC) coefficient between the VLTrad and the VLTs predicted by the model (VLTmodel). The performance of the model was also compared two metrics, peak signal-to-noise ratio (PSNR) and high-dynamic range visual difference predictor (HDRVDP). The time for computing VLTs between MLR model, PSNR, and HDRVDP were compared using the repeated ANOVA with a post-hoc analysis. P?<?0.05 was considered to indicate a statistically significant difference.Results
The means of absolute differences with the VLTrad were 0.58 (95% CI, 0.48, 0.67), 0.73 (0.61, 0.85), and 0.68 (0.58, 0.79), for the MLR model, PSNR, and HDRVDP, respectively, showing significant difference between them (p?<?0.01). The ICC coefficients of MLR model, PSNR, and HDRVDP were 0.88 (95% CI, 0.81, 0.95), 0.85 (0.79, 0.91), and 0.84 (0.77, 0.91). The computing times for calculating VLT per image were 1.5?±?0.1 s, 3.9?±?0.3 s, and 68.2?±?1.4 s, for MLR metric, PSNR, and HDRVDP, respectively.Conclusions
The proposed MLR model directly predicting the VLT of a given CT image showed competitive performance to those of image fidelity metrics with less computational expenses. The model would be promising to be used for adaptive compression of CT images.75.
Lukáš Školoudík Viktor Chrobok Zuzana Kočí Jiří Popelář Josef Syka Jan Laco Alžběta Filipová Eva Syková Stanislav Filip 《Stem cell reviews》2018,14(6):860-870
Temporal bone reconstruction is a persisting problem following middle ear cholesteatoma surgery. Seeking to advance the clinical transfer of stem cell therapy we attempted the reconstruction of temporal bone using a composite bioartificial graft based on a hydroxyapatite bone scaffold combined with human bone marrow-derived mesenchymal stromal cells (hBM-MSCs). The aim of this study was to evaluate the effect of the combined biomaterial on the healing of postoperative temporal bone defects and the preservation of physiological hearing functions in a guinea pig model. The treatment’s effect could be observed at 1 and 2 months after implantation of the biomaterial, as opposed to the control group. The clinical evaluation of our results included animal survival, clinical signs of an inflammatory response, and exploration of the tympanic bulla. Osteogenesis, angiogenesis, and inflammation were evaluated by histopathological analyses, whereas hBM-MSCs survival was evaluated by immunofluorescence assays. Hearing capacity was evaluated by objective audiometric methods, i.e. auditory brainstem responses and otoacoustic emission. Our study shows that hBM-MSCs, in combination with hydroxyapatite scaffolds, improves the repair of bone defects providing a safe and effective alternative in their treatment following middle ear surgery due to cholesteatoma. 相似文献
76.
Wonmin Ko Jin-Soo Park Kwan-Woo Kim Jongwon Kim Youn-Chul Kim Hyuncheol Oh 《Inflammation》2018,41(4):1215-1228
Four nardosinone-type sesquiterpenes, nardosinone, isonardosinone, kanshone E, and kanshone B, were isolated from the hexane fraction of Nardostachys jatamansi (Valerianaceae) methanol extract. The structures of these compounds were mainly established by analyzing the data obtained from nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). In this study, we investigated their anti-neuroinflammatory effects in lipopolysaccharide (LPS)-induced BV2 microglial cells. The results showed that nardosinone-type sesquiterpenes inhibited the production of pro-inflammatory mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-induced BV2 microglial cells. These inhibitory effects were correlated with the downregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, these sesquiterpenes also attenuated the mRNA expression of pro-inflammatory cytokines including interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) in LPS-induced BV2 microglial cells. During the evaluation of the signaling pathways involved in these anti-neuroinflammatory effects, western blot analysis and DNA-binding activity assay revealed that the suppression of inflammatory reaction by these sesquiterpenes was mediated by the inactivation of nuclear factor-kappa B (NF-κB) pathway. These sesquiterpenes also suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways in LPS-stimulated BV2 microglial cells. Taken together, these four nardosinone-type sesquiterpenes inhibited NF-κB- and MAPK-mediated inflammatory pathways, demonstrating their potential role in the treatment of neuroinflammation conditions. 相似文献
77.
78.
Albert Konijnenberg Duygu Yilmaz Helgi I. Ingólfsson Anna Dimitrova Siewert J. Marrink Zhuolun Li Catherine Vénien-Bryan Frank Sobott Arma?an Ko?er 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(48):17170-17175
Mechanosensitive ion channels are sensors probing membrane tension in all species; despite their importance and vital role in many cell functions, their gating mechanism remains to be elucidated. Here, we determined the conditions for releasing intact mechanosensitive channel of large conductance (MscL) proteins from their detergents in the gas phase using native ion mobility–mass spectrometry (IM-MS). By using IM-MS, we could detect the native mass of MscL from Escherichia coli, determine various global structural changes during its gating by measuring the rotationally averaged collision cross-sections, and show that it can function in the absence of a lipid bilayer. We could detect global conformational changes during MscL gating as small as 3%. Our findings will allow studying native structure of many other membrane proteins.One of the best candidates to explore the gating of mechanosensitive channels is the mechanosensitive channel of large conductance (MscL) from Escherichia coli. The crystal structure of MscL in its closed/nearly closed state from Mycobacterium tuberculosis revealed this channel as a homopentamer (1). Each subunit has a cytoplasmic N- and C-terminal domain as well as two α-helical transmembrane (TM) domains, TM1 and TM2, which are connected by a periplasmic loop. The five TM1 helices form the pore and the more peripheral TM2 helices interact with the lipid bilayer.MscL detects changes in membrane tension invoked by a hypoosmotic shock and couples the tension sensing directly to large conformational changes (1, 2). On the basis of a large body of structural and theoretical data, numerous gating models of MscL have been proposed (3–9). These models agree upon (i) the hydrophobic pore constriction of the channel and (ii) the channel opens by an iris-like rotation—i.e., a tilting and outward movement of transmembrane helices that make the channel wider and shorter (5). This mechanism is supported by patch-clamp (10), disulfide cross-linking (11), FRET spectroscopy (12), and site-directed spin labeling EPR experiments (6, 7), as well as computational studies (13–15). So far, direct experimental results have only been observed for short-range local structural changes, and no measure of the overall global structural changes during channel gating have been reported. Because there is no crystal structure available for the open MscL channel, elucidating overall global structural changes from the onset of channel activation is of utmost importance for our understanding of the gating mechanism of mechanosensitive channels. Here, we provide direct experimental evidence for the key areal changes occurring during channel gating by combining our ability to activate MscL in a controlled manner to different subopen states (16) with a native ion mobility-mass spectrometry (IM-MS) approach. 相似文献
79.
Objective:To present a patient treated with submerging autotransplantation (SA) of an immature premolar and subsequent orthodontic space closure (OSC) and to report a 10-year follow-up result.Case and Method:A 10-year-old boy had multiple missing premolars with an asymmetric pattern (maxillary right first and second premolars, teeth 14 and 15; maxillary left second premolar, tooth 25; and mandibular right second premolar, tooth 45). After considering several treatment options, tooth 35 with immature root development underwent SA into the missing site of tooth 15 at a depth 5 mm below the occlusal plane and was stabilized with sutures to create a symmetric missing condition of the premolars in the four quadrants.Results:Three months after autotransplantation, spontaneous eruption of the transplanted tooth was observed. Nine months after autotransplantation, presence of the lamina dura of the transplanted tooth was confirmed with a periapical radiograph. Active orthodontic treatment was initiated to reduce lip protrusion by closing the missing spaces of teeth 14, 25, 35, and 45 and to correct dental midline deviation. After 33 months of active orthodontic treatment, Class I canine and molar relationships were obtained. During the 10-year follow-up, the pulp vitality of the transplanted tooth was maintained without any pathologic findings, including root resorption or pulp canal obliteration.Conclusions:In a patient with lip protrusion and multiple congenitally missing premolars with an asymmetric pattern, SA of one premolar from the normal quadrant into the quadrant missing two premolars with subsequent OSC of the missing sites of the other premolars can be an effective treatment modality. 相似文献
80.