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971.
Gianni Ciofani Giada G. Genchi Ioannis Liakos Valentina Cappello Mauro Gemmi Athanassia Athanassiou Barbara Mazzolai Virgilio Mattoli 《Pharmaceutical research》2013,30(8):2133-2145
Purpose
Oxidative stress has been found to play a key role in several diseases, that range from cancer to neurodegenerative disorders. Besides traditional anti-oxidant agents, in recent years much attention has been focused on nanotechnological solutions, including cerium oxide nanoparticles (nanoceria).Methods
Thanks to its extraordinary catalytic properties, nanoceria mimics the activity of superoxide dismutase and of catalase, therefore acting as a reactive oxygen species (ROS) scavenger in many biological contexts. In this paper, we report on nanoceria interactions with PC12 cell line, that represents a valuable model for many features of central dopaminergic neurons.Results
Nanoceria confirmed a strong anti-ROS action but, most interestingly, also showed beneficial effects on both cell differentiation and dopamine production.Conclusions
Even if deeper examinations will be necessary in order to better clarify the mechanisms at the base of the documented effects, nanoceria demonstrated a significant potential as pharmacological agent in the treatment of neurological disorders. 相似文献972.
Aikaterini Mastoraki Victoria Chatzimavridou-Grigoriadou Varvara Chatzipetrou Sotiria Mastoraki Ioannis S. Papanikolaou Nikolaos Danias Vasilios Smyrniotis Nikolaos Arkadopoulos 《Journal of gastrointestinal cancer》2014,45(3):256-261
Background
Familial predisposition characterizes up to 10 % of the patients with pancreatic cancer (PC). Although many syndromes have been associated with an increased risk for PC, familial pancreatic cancer (FPC) accounts for the majority of hereditary cases. FPC is defined by families with at least a pair of first-degree relatives (FDRs) who have been diagnosed with PC and do not fulfill the criteria of other inherited tumor syndromes.Methods and Results
Genetic counseling is of great importance to estimate the prevalence and recommend further molecular testing. Regarding the screening program for individuals with increased risk for PC, a consortium summit stated that candidates for screening are FDRs of patients with PC from a familial kindred with at least two affected FDRs, patients with Peutz–Jeghers syndrome and p16, BRCA2, and hereditary nonpolyposis colorectal cancer (HNPCC) mutation carriers. It was also agreed that initial screening should include endoscopic ultrasonography (EUS) and/or magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) instead of computed tomography (CT) or endoscopic retrograde cholangiopancreatography (ERCP).Conclusions
However, the optimal age of initial screening remains undefined. Furthermore, a multidisciplinary assessment is required to determine whether surgical interventions should be performed at high-volume specialty centers. The aim of this study is to collect all the recent information considering the genetic basis, screening protocols, and treatment of FPC in order to provide an update on the current contemporary concepts of therapeutic management of the disease. 相似文献973.
Objective: To introduce and evaluate an alternative technique for accessing the lumbar facet joints. This technique uses an oblique approach to enter the facet joint without the need to rotate the patient towards the beam. Methods and Material: The proposed technique was employed in 23 consecutive patients (50 joints) with diagnosed or suspected facet joint syndrome. We recorded the success rate, the time spent to complete the procedure, and any complications arisen. Results: The overall success rate was 84% and the average time spent for the procedure was 4.8 min. No complications were encountered. Conclusions: Due to its inherent simplicity the proposed technique is easily tolerated by the patient, has a high success rate and can be performed quickly without complications. 相似文献
974.
Imaging and localization of pancreatic insulinomas 总被引:6,自引:0,他引:6
Chatziioannou A Kehagias D Mourikis D Antoniou A Limouris G Kaponis A Kavatzas N Tseleni S Vlachos L 《Clinical imaging》2001,25(4):275-283
For pancreatic insulinomas, the treatment of choice is surgical excision, which when successful is curative. Intraoperative palpation combined with ultrasonography theoretically depict almost all tumors, however the accuracy of palpation is improved by the preoperative localization. All recent advances in imaging have improved the likelihood for curative surgical resection. Our purpose is to demonstrate the characteristics of all modalities, which may be used in the preoperative localization algorithm. 相似文献
975.
Konstantinos T. Tsaousis Panagiotis G. Karagiannidis Nikolaos Kopsachilis Chrysanthos Symeonidis Ioannis T. Tsinopoulos Varvara Karagkiozaki Lampros P. Lamprogiannis Stergios Logothetidis 《International ophthalmology》2014,34(3):519-523
The purpose of the study was to appraise the effect of loading force magnitude on the determination of the elastic modulus of the anterior lens capsule through atomic force microscopy. Four human anterior lens capsules taken during phacoemulsification cataract surgery were studied, free of epithelial cells, with atomic force microscopy. For the experiment, five different indentation loading forces were applied to near areas of the specimen. Experimental data was exported and analyzed according to the Hertz model to obtain the Young’s modulus with regards to the elastic behavior of the material. Force–distance curves were acquired by applying a load of 2, 5, 10, 20 and 30 nN. When examining the results it was evident that determination of Young’s modulus of the anterior lens capsule is dependent on the loading force concerning the examined range. Loading forces of 10 and 20 nN led to results without significant difference (p > 0.05) and more reproducible (coefficients of variation 12.4 and 11.7 %, respectively). 相似文献
976.
Efstathios T. Detorakis Alexandra Karavitaki Nela Stojanovic George Kontadakis Ioannis G. Pallikaris 《International ophthalmology》2014,34(4):781-786
This study employs optical coherence tomography (OCT) and ultrasound biomicroscopy (UBM) imaging as well as optical aberrometry to examine correlations between the anterior chamber angle aperture and visual acuity for near vision as well as coma along the horizontal and vertical axes in eyes implanted with an accommodative intraocular lens (Crystalens). A retrospective comparative consecutive case series of 22 eyes of 11 patients (5 males) uneventfully implanted with a Crystalens. Eyes with signs of posterior capsular opacification were excluded. All eyes were examined with 40 MHz UBM (Ellex Eyecubed) and spectral-domain OCT (Zeiss Visante). The angle aperture along the horizontal and vertical meridians was recorded based on the software of the systems. The coma root mean square (RMS) scores for the horizontal and vertical meridians were also recorded with the iTrace aberrometer. The anterior chamber angle was significantly wider along the horizontal axis compared with the vertical axis by UBM (46.37° and 44.20°, respectively) and by OCT (46.79° and 43.58°, respectively) (p = 0.02 in both cases, paired-samples t test). The correlations between the logMAR-converted Jaeger near vision score and the horizontal or vertical angle apertures was not statistically significant. Horizontal coma RMS was significantly inversely correlated with the horizontal angle aperture (r = ?0.45, p = 0.03 and r = ?0.39, p = 0.04 by OCT and UBM, respectively). Measurement of the horizontal angle aperture by the modalities used may represent an anatomical and clinical predictor of the optical aberrations induced by the Crystalens. 相似文献
977.
Chih-Han Kung Mats Lindblad Magnus Nilsson Ioannis Rouvelas Koshi Kumagai Lars Lundell Jon A. Tsai 《Gastric cancer》2014,17(3):571-577
Background
Limited information is available on the incidence of postoperative pancreatic fistula (POPF) after D2 gastrectomy with the strict use of the International Study Group of Pancreatic Fistula (ISGPF) criteria, particularly so in Western patients.Methods
All patients who underwent gastrectomy for adenocarcinoma at the Karolinska University Hospital Huddinge from 2006 until June 2012 were identified via hospital records and reviewed for type of surgical procedure, postoperative morbidity, incidence, and risk factors for POPF.Results
Ninety-two of 107 cases had a D2 gastrectomy eligible for evaluation of POPF, of which 83 (90 %) also underwent bursectomy. Seven patients fulfilled the criteria for POPF grade A (7.6 %), 5 met the criteria for POPF grade B (5.4 %), and 6 the criteria for POPF grade C (6.5 %). The incidence of POPF grade B or C was 4.9 % among the 82 patients for whom no pancreatic resection was performed and 70 % among 10 cases with concomitant pancreatic resection. The latter (OR 156.2, 95 % CI 8.00–3046.93) and age (OR 1.2, 95 % CI 1.02–1.35) were found to be the only risk factors for POPF after gastrectomy upon a multivariate analysis.Conclusions
In this series of Western patients, POPF grade B or C according to the ISGPF criteria was uncommon after D2 gastrectomy without pancreatic resection. Bursectomy was not a risk factor for POPF. 相似文献978.
Helena M Earl Anne-Laure Vallier Louise Hiller Nicola Fenwick Jennie Young Mahesh Iddawela Jean Abraham Luke Hughes-Davies Ioannis Gounaris Karen McAdam Stephen Houston Tamas Hickish Anthony Skene Stephen Chan Susan Dean Diana Ritchie Robert Laing Mark Harries Carlos Caldas 《The lancet oncology》2014,15(2):201-212
979.
Castagna O Brisswalter J Lacour JR Vogiatzis I 《European journal of applied physiology》2008,104(6):1061-1067
The introduction of the new Olympic class windsurf-board has prompted sailors to develop a new technique of sail “pumping”
(rhythmically pulling the sail so that it acts as a wing). Contrary to the old technique that mainly involved upper body activity,
the new one requires both upper and lower body muscle activity. Accordingly, the aim of the present study was to compare the
performance characteristics of the board (speed and pointing angle ability relative to the direction of the wind) as well
as the sailors’ physiological demands during sail pumping with the old and new pumping techniques. Nineteen male, highly-trained
(O2max: 65.1 ± 5.9 ml min−1 kg−1), international level windsurfers from six different countries underwent two testing sessions on-water in a balanced order.
Compared to the old pumping technique the mean distance sailed with the new technique (1,872 ± 15 and 1,764 ± 13 m, respectively)
and the board speed (3.42 ± 0.49 and 3.81 ± 0.28 m s−1, respectively) were significantly (P < 0.05) shorter and greater, respectively. Consequently, the time taken to sail the testing course was significantly shorter
with the new compared to the old technique (390 ± 8 vs. 420 ± 16 s). Despite the finding that the new technique was sustained
at a significantly higher fraction of O2max (80.5 ± 5.2 and 72.7 ± 4.5%, respectively) compared to the old technique, total energy expenditure (130.7 ± 11.3 and 128.1 ± 9.2 Kcal,
respectively) and blood lactate concentration 3 min into recovery (9.4 ± 2.2 and 8.5 ± 1.7 mmol l−1, respectively) were not different. It is concluded that application of the new sail pumping technique improves the performance
characteristics of the board without increasing the sailors’ total metabolic requirement. 相似文献
980.
Clusterin is a broadly distributed glycoprotein constitutively expressed by various tissues and cell types and has been shown to be associated with several physiological and pathological functions. In order to study the molecular evolution of clusterin, here we report the cloning and characterization of two clusterin genes in rainbow trout (Oncorhynchus mykiss). The deduced amino acid sequences of clusterin-1 and a partial clusterin-2 clone are 89% identical to each other, showing 45, 42 and 38% identity with chicken, frog and human orthologs, respectively. Most of the putative N-glycosylation sites, as well as all 10 cysteine residues which are involved in disulfide bond formation in the mature trout clusterin-1 protein, are fully conserved when aligned with its orthologs from various species. Although trout clusterin genes exhibit the same exon-intron organization, in line with that of human clusterin, they show a totally different mRNA expression profile among various trout tissues. Phylogenetic analysis indicates an early segregation of the clusterin ancestral gene within the taxon of fish leading to the formation of a separate subgroup. 相似文献