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排序方式: 共有261条查询结果,搜索用时 15 毫秒
81.
Carlo Cosimo Quattrocchi Maria Francesca de Pandis Claudia Piervincenzi Manuela Galli Jean Marc Melgari Gaetano Salomone Patrizio Sale Carlo Augusto Mallio Filippo Carducci Fabrizio Stocchi 《PloS one》2015,10(10)
Objective
The present study shows the results of a double-blind sham-controlled pilot trial to test whether measurable stimulus-specific functional connectivity changes exist after Automatic Mechanical Peripheral Stimulation (AMPS) in patients with idiopathic Parkinson Disease.Methods
Eleven patients (6 women and 5 men) with idiopathic Parkinson Disease underwent brain fMRI immediately before and after sham or effective AMPS. Resting state Functional Connectivity (RSFC) was assessed using the seed-ROI based analysis. Seed ROIs were positioned on basal ganglia, on primary sensory-motor cortices, on the supplementary motor areas and on the cerebellum. Individual differences for pre- and post-effective AMPS and pre- and post-sham condition were obtained and first entered in respective one-sample t-test analyses, to evaluate the mean effect of condition.Results
Effective AMPS, but not sham stimulation, induced increase of RSFC of the sensory motor cortex, nucleus striatum and cerebellum. Secondly, individual differences for both conditions were entered into paired group t-test analysis to rule out sub-threshold effects of sham stimulation, which showed stronger connectivity of the striatum nucleus with the right lateral occipital cortex and the cuneal cortex (max Z score 3.12) and with the right anterior temporal lobe (max Z score 3.42) and of the cerebellum with the right lateral occipital cortex and the right cerebellar cortex (max Z score 3.79).Conclusions
Our results suggest that effective AMPS acutely increases RSFC of brain regions involved in visuo-spatial and sensory-motor integration.Classification of Evidence
This study provides Class II evidence that automatic mechanical peripheral stimulation is effective in modulating brain functional connectivity of patients with Parkinson Disease at rest.Trial Registration
Clinical Trials.gov NCT01815281 相似文献82.
Francesco Chiavaioli Cosimo Trono Ambra Giannetti Massimo Brenci Francesco Baldini 《Journal of biophotonics》2014,7(5):312-322
Optical fibre gratings, especially long period gratings, have been recently proposed as optical devices for biochemical sensing. A biochemical interaction along the grating portion induces a refractive index change and hence a change in the fiber transmission spectrum. This provides an alternative methodology with respect to other label‐free optical approaches, such as surface plasmon resonance, interferometric configurations and optical resonators. The fibre biofunctionalization has been carried out by means of a novel chemistry using Eudragit L100 copolymer as opposed to the commonly used silanization procedure. Antigen‐antibody interaction has been analysed by means of an IgG/anti‐IgG bioassay. The biosensor was fully characterised, monitoring the kinetics during the antibody immobilization and the antigen interaction and achieving the calibration curve of the assay. A comparison of the biosensor performance was made by using two different long period gratings with distinct periods. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
83.
Eugenio Bortolini Luca Pagani Gregorio Oxilia Cosimo Posth Federica Fontana Federica Badino Tina Saupe Francesco Montinaro Davide Margaritora Matteo Romandini Federico Lugli Andrea Papini Marco Boggioni Nicola Perrini Antonio Oxilia Riccardo Aiese Cigliano Rosa Barcelona Davide Visentin Stefano Benazzi 《Current biology : CB》2021,31(11):2484-2493.e7
84.
Soldatini C Albores-Barajas YV Lovato T Andreon A Torricelli P Montemaggiori A Corsa C Georgalas V 《PloS one》2011,6(12):e28920
The presence of wildlife in airport areas poses substantial hazards to aviation. Wildlife aircraft collisions (hereafter wildlife strikes) cause losses in terms of human lives and direct monetary losses for the aviation industry. In recent years, wildlife strikes have increased in parallel with air traffic increase and species habituation to anthropic areas. In this paper, we used an ecological approach to wildlife strike risk assessment to eight Italian international airports. The main achievement is a site-specific analysis that avoids flattening wildlife strike events on a large scale while maintaining comparable airport risk assessments. This second version of the Birdstrike Risk Index (BRI2) is a sensitive tool that provides different time scale results allowing appropriate management planning. The methodology applied has been developed in accordance with the Italian Civil Aviation Authority, which recognizes it as a national standard implemented in the advisory circular ENAC APT-01B. 相似文献
85.
Achilli A Olivieri A Pala M Hooshiar Kashani B Carossa V Perego UA Gandini F Santoro A Battaglia V Grugni V Lancioni H Sirolla C Bonfigli AR Cormio A Boemi M Testa I Semino O Ceriello A Spazzafumo L Gadaleta MN Marra M Testa R Franceschi C Torroni A 《PloS one》2011,6(6):e21029
Mitochondrial dysfunction has been implicated in rare and common forms of type 2 diabetes (T2DM). Additionally, rare mitochondrial DNA (mtDNA) mutations have been shown to be causal for T2DM pathogenesis. So far, many studies have investigated the possibility that mtDNA variation might affect the risk of T2DM, however, when found, haplogroup association has been rarely replicated, even in related populations, possibly due to an inadequate level of haplogroup resolution. Effects of mtDNA variation on diabetes complications have also been proposed. However, additional studies evaluating the mitochondrial role on both T2DM and related complications are badly needed. To test the hypothesis of a mitochondrial genome effect on diabetes and its complications, we genotyped the mtDNAs of 466 T2DM patients and 438 controls from a regional population of central Italy (Marche). Based on the most updated mtDNA phylogeny, all 904 samples were classified into 57 different mitochondrial sub-haplogroups, thus reaching an unprecedented level of resolution. We then evaluated whether the susceptibility of developing T2DM or its complications differed among the identified haplogroups, considering also the potential effects of phenotypical and clinical variables. MtDNA backgrounds, even when based on a refined haplogroup classification, do not appear to play a role in developing T2DM despite a possible protective effect for the common European haplogroup H1, which harbors the G3010A transition in the MTRNR2 gene. In contrast, our data indicate that different mitochondrial haplogroups are significantly associated with an increased risk of specific diabetes complications: H (the most frequent European haplogroup) with retinopathy, H3 with neuropathy, U3 with nephropathy, and V with renal failure. 相似文献
86.
Robert N. Judson Stuart R. Gray Claire Walker Andrew M. Carroll Cecile Itzstein Arimantas Lionikas Peter S. Zammit Cosimo De Bari Henning Wackerhage 《PloS one》2013,8(3)
The aim of this study was to investigate the function of the Hippo pathway member Yes-associated protein (Yap, gene name Yap1) in skeletal muscle fibres in vivo. Specifically we bred an inducible, skeletal muscle fibre-specific knock-in mouse model (MCK-tTA-hYAP1 S127A) to test whether the over expression of constitutively active Yap (hYAP1 S127A) is sufficient to drive muscle hypertrophy or stimulate changes in fibre type composition. Unexpectedly, after 5–7 weeks of constitutive hYAP1 S127A over expression, mice suddenly and rapidly lost 20–25% body weight and suffered from gait impairments and kyphosis. Skeletal muscles atrophied by 34–40% and the muscle fibre cross sectional area decreased by ≈40% when compared to control mice. Histological analysis revealed evidence of skeletal muscle degeneration and regeneration, necrotic fibres and a NADH-TR staining resembling centronuclear myopathy. In agreement with the histology, mRNA expression of markers of regenerative myogenesis (embryonic myosin heavy chain, Myf5, myogenin, Pax7) and muscle protein degradation (atrogin-1, MuRF1) were significantly elevated in muscles from transgenic mice versus control. No significant changes in fibre type composition were detected using ATPase staining. The phenotype was largely reversible, as a cessation of hYAP1 S127A expression rescued body and muscle weight, restored muscle morphology and prevented further pathological progression. To conclude, high Yap activity in muscle fibres does not induce fibre hypertrophy nor fibre type changes but instead results in a reversible atrophy and deterioration. 相似文献
87.
Aimed at understanding the crucially important structural features for the integrity of α-helical mimicry by βγ-sequences,
an α-amino acid sequence in a native peptide was substituted by differently arranged βγ-sequences. The self- and hetero-assembly
of a series of αβγ-chimeric sequences based on a 33-residue GCN4-derived peptide was investigated by means of molecular dynamics,
circular dichroism, and a disulfide exchange assay. Despite the native-like behavior of βγ alternating sequences such as retention
of α-helix dipole and the formation of 13-membered α-helix turns, the αβγ-chimeras with different βγ substitution patterns
do not equally mimic the structural behavior of the native parent peptide in solution. The preservation of the key residue
contacts such as van der Waals interactions and intrahelical H-bonding, which can be met only by particular substitution patterns,
thermodynamically favor the adoption of coiled coil folding motif. In this study, we show how successfully the destabilizing
structural consequences of α → βγ modification can be harnessed by reducing the solvent-exposed hydrophobic surface area and
placing of suitably long and bulky helix-forming side chains at the hydrophobic core. The pairing of αβγ-chimeric sequences
with the native wild-type are thermodynamically allowed in the case of ideal arrangement of β- and γ-residues. This indicates
a similarity in local side chain packing of β- and γ-amino acids at the helical interface of αβγ-chimeras and the native α-peptide.
Consequently, the backbone extended residues are able to participate in classical “knob-into-hole” packing with native α-peptide. 相似文献
88.
89.
90.
Iranshahi M Arfa P Ramezani M Jaafari MR Sadeghian H Bassarello C Piacente S Pizza C 《Phytochemistry》2007,68(4):554-561
Two new sesquiterpene coumarins, named szowitsiacoumarin A (1) and szowitsiacoumarin B (2), and a phenylpropanoid derivative, 2-epihelmanticine (3), together with nine known compounds, auraptene (4), umbelliprenin (5), galbanic acid (6), methyl galbanate (7), farnesiferol B (8), farnesiferol C (9), persicasulfide A (10), beta-sitosterol and stigmasterol were isolated from the roots of Ferula szowitsiana. The structures of these compounds were elucidated by extensive spectroscopic methods including 1D-((1)H and (13)C) and 2D-NMR experiments (DQF-COSY, HSQC, HMBC, and ROESY) as well as HR-MALDI-MS analysis. Since the configuration of 2-epihelmanticine was previously only partly determined, a relative configurational analysis of its four stereocenters was carried out on the basis of the recently reported J-based method. The inhibiting activity of prenylated coumarins, auraptene (4) and umbelliprenin (5), in addition to galbanic acid (6), as major component, and of the Me(2)CO extract of Ferula szowitsiana (Apiaceae) roots has been evaluated against promastigotes of Leishmania major. Umbelliprenin and auraptene showed significant activity with IC(50) values of 4.9microg/ml (13.3microM) and 5.1microg/ml (17.1microM) after 48h incubation, respectively. 相似文献