303 research outputs found

    The role of cochlear implant positioning on MR imaging quality: a preclinical in vivo study with a novel implant magnet system

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    Purposes: To investigate the effects for Ultra 3D cochlear implant (CI) positioning on MR imaging quality, looking at a comprehensive description of intracranial structures in cases of unilateral and bilateral CI placement. Methods: Four CI angular positions (90°, 120°, 135° and 160°) at 9 cm distance from the outer-ear canal were explored. The 1.5 T MRI assessment included our institutional protocol for the investigation of brain pathologies without gadolinium application. Three investigators (two experienced neuroradiologists and one experienced otoneurosurgeon) independently evaluated the MR findings. A 4-point scale was adopted to describe 14 intracranial structures and to determine which CI positioning allowed the best image quality score and how bilateral CI placement modified MRI scan visibility. Results: A high positive correlation was found between the three blinded observers. Structures situated contralateral from the CI showed high-quality values in all four placements. Structures situated ipsilaterally provided results suitable for diagnostic purposes for at least one position. At 90°, artifacts mainly involved brain structures located cranially and anteriorly (e.g., temporal lobe); on the contrary, at 160°, artifacts mostly influenced the posterior fossa structures (e.g., occipital lobe). For the bilateral CI condition, MR imaging examination revealed additional artifacts involving all structures located close to either CI, where there was a signal void/distortion area. Conclusions: Suitable unilateral CI positioning can allow the visualization of intracranial structures with sufficient visibility for diagnostic purposes. Bilateral CI positioning significantly deteriorates the anatomical visibility. CI positioning might play a crucial role for patients who need post-operative MRI surveillance

    Phytochemical and biological characterization of dry outer scales extract from Tropea red onion (Allium cepa L. var. Tropea)–A promising inhibitor of pancreatic lipase

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    Background: Allium cepa L. var. Tropea is typically cultivated in Calabria (Italy) and it is certified as “Cipolla Rossa di Tropea Calabria-PGI” (Tropea red onion). The use of clinically available anti-obesity drugs such as Orlistat is being gradually dismissed due to their side-effects and this has encouraged the search for alternative inhibitors of intestinal lipases such as phytochemicals showing less side-effects. In this study we aimed to evaluate for the first time the anti-obesity potential of the hydroalcoholic extract from the dry outer scales of Tropea red onion by the assesment of its capacity to inhibit pancreatic lipase. Its possible mechanism of action was also studied with planar lipid membranes (PLMs) surrogate of intestinal membranes. Methods: Specialized metabolites in the extract were determined by GC–MS, HPLC-DAD, HPLC-UV-DAD and HPLC-HRMS analyses. Inhibition of pancreatic lipase was studied in vitro against crude lipase Type II from porcine pancreas. PLMs used in the electrophysiology measurements were made up of DOPS:DOPE:POPC. Results: The extract contained quercetin-4′-O-glucoside, quercetin and quercetin-3,4′-O-diglucoside as the most abundant phenolics. Among apolar constituents, γ-sitosterol, linoleic and stearic acids were dominant. The lipase inhibitory effect of the extract had an IC50 value equal to 0.77±0.03 mg/mL (positive control, IC50 = 0.018 mg/mL). The electrophysiological study demonstrated that the extract is able to incorporate into PLMs and to form transient channel-like events Conclusions: Taken altogether, the results allow us to suggest that the hydroalcoholic extract from the dry outer scales of Tropea red onion could prevent lipid ester hydrolysis and it has a protective effect against phospholipase as found for interfacially active compounds

    Chemical identification of specialized metabolites from sulla (Hedysarum coronarium l.) collected in southern italy

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    Sulla (Hedysarum coronarium L.) is a biennal forage legume originated from the Mediterranean basin and used for animal feeding due to its high forage quality and palatability. Several species of Hedysarum have been considered for their nutritional, pharmaceutical, and biological properties, and different applications have been reported, both for human consumption and animal nutrition. Although a systematic investigation of the chemical constituents of Hedysarum spp. has been performed in order to provide chemotaxonomic evidences for the genus and to support the pharmacological application of several species within the genus, few data are available on the chemical constituents of H. coronarium, and only the content of condensed tannins and flavonoids in leaves has been previously reported. In the present paper, results from a detailed chemical analysis of the extracts from the leaves and flowers of H. coronarium grown wild in southern Italy are presented. Identification of the main specialized metabolites within the chemical classes of flavonoids, proanthocyanidins and saponins, is described, including considerations on their content in the two plant organs. Information acquired from this study expands the knowledge on H. coronarium as a source of valuable phytochemicals for different applications in human and animal health and nutrition

    Bulging of the Oval Window in Common Cavity Deformity: A Possible Predictor of Meningitis

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    Objective:To investigate the prevalence-rate of oval window bulging in the common cavity and its association with bacterial meningitis.Patients:CT and clinical files of 29 children with preliminary diagnosis of common cavity deformity were collected from 13 Italian centers.Intervention:A retrospective case review study was conducted with a centralized evaluation of the temporal bone CT imaging was performed at Azienda Ospedale - Università Padova, Padova, Italy.Main Outcome Measure:Diagnosis of common cavity was reviewed; in addition, a fluid protrusion into the middle-ear cavity through the oval window at CT imaging was considered as oval window bulging. Its association with the history of bacterial meningitis was investigated.Results:Common cavity deformity was confirmed in 14/29 children (mean-age 11.4 ± 3.8; age-range 5-20; nine females) referred with this diagnosis. In 7/14 patients, the common cavity deformity was bilateral (i.e., 21 common cavities). Oval window bulging was found in 3/19 common cavities (concomitant middle-ear effusive otitis hampered the evaluation in two cases), while the internal acoustic meatus fundus was defective in 10/21 cases. History of bacterial meningitis was found in three children (21%) and two of them had oval window bulging at CT. In the case unrelated to oval window bulging, meningitis occurred late at the age of 12 during acute otitis contralateral to common cavity deformity (ipsilaterally to incomplete partition type 1).Conclusion:Patients harboring common cavity deformity have a high risk of meningitis in their first years of life. Oval window bulging seems to be associated with a higher risk of meningitis. This information might be important for appropriate surgical planning

    Retrosigmoidal placement of an active transcutaneous bone conduction implant: Surgical and audiological perspectives in a multicentre study

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    Introduction. The retrosigmoidal (RS) placement of the Bonebridge system (BB) has been advocated for cases of unfavourable anatomical or clinical conditions which contraindi-cate transmastoid-presigmoidal positioning. However, these disadvantageous conditions, combined with the considerable dimensions of the implant, may represent a challenge, especially for surgeons with no skull base experience. Moreover, the literature reports only limited experience concerning RS implantation of the BB system. Methods. A multicentre, retrospective study was conducted to analyse the surgical and functional outcomes of a wide population of patients undergoing RS placement of the BB system by means of a surgical technique specifically developed to overcome the intraopera-tive issues related to this surgery. Twenty patients with conductive or mixed hearing loss and single sided deafness were submitted to RS implantation of the BB system. Results. Audiological assessment concerning the measurement of the functional and effective gain by pure-tone audiometry (28 dB HL and-12.25 dB HL, respectively) and speech audiometry (24.7 dB HL and-21 dB HL, respectively) was conducted. A high overall sub-jective improvement of quality of life was recorded with the Glasgow Benefit Inventory questionnaire. No major complications, such as device extrusions or other conditions re-quiring revision surgery, were reported during the follow-up period (median: 42 months). Conclusions. In our study, which has one of the largest cohort of patients reported in the literature, RS placement of the BB system was safe and effective. Our functional results showed comparable hearing outcomes with presigmoidal placement. The effective gain, rarely investigated in this field, may be the object of further research to improve our under-standing of bone conduction mechanisms exploited by bone conduction hearing implants

    MRI-induced artifact by a cochlear implant with a novel magnet system: an experimental cadaver study

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    Purposes: To primarily evaluate MRI-induced effects for Ultra 3D cochlear implantation in human cadavers in terms of artifact generation and MR image quality. Methods: Three human cadaveric heads were submitted to imaging after unilateral and bilateral cochlear implantation. The 1.5 T MR examination protocol was chosen in accordance with our institutional protocol for the assessment of brain pathology. The maximal signal void size was measured according to each sequence and plane. Two experienced neuro-radiologists and one experienced otoneurosurgeon independently evaluated the MR image quality findings. A 4-point scale was used to describe the diagnostic usefulness of 14 brain structures. Results: Shape and size of the artifacts were found to be highly related to MRI sequences and acquisition planes. MRI sequences and processing algorithms affected the ability to assess anatomical visibility. Image quality appeared either high or assessable for diagnostic purposes in 9 out of 14 of the ipsilateral structures, in at least one plane. Anatomical structures contralateral to the cochlear implant were highly visible in all conditions. Artifact intrusion clearly improved after application of metal artifact-reduction techniques. In the case of bilateral cochlear implant, a mutual interaction between the two implant magnets produced an additional artifact. Conclusions: We performed the first cadaver study aimed at systematically evaluating the MRI-induced artifacts produced by a cochlear implant with a novel four bar magnet system. Specific brain structures can be assessable for diagnostic purposes under 1.5 T MRI, with the cochlear implant magnet in place

    Triterpenic saponins from Medicago marina L

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    The saponin composition of leaves and roots from Medicago marina L., sea medic, was investigated by a combination of chromatographic, spectroscopic and spectrometric (GC, LC, ESI-MS/MS, NMR) methods. Several compounds were detected and quantified by HPLC using the external standard method. Saponins from this plant species consist of a mixture of high molecular weight bidesmosidic derivatives of medicagenic and zanhic acid, containing up to six sugars in the molecules. Six of the detected saponins were previously isolated and reported as constituents of other Medicago spp.; one saponin was previously described in other plant species; four saponins are undescribed compounds in Medicago and never reported before in other plant species. These are: 3-O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosylzanhic acid 28-O-β-D-xylopyranosyl-(1 → 4)-[β-D-apiofuranosyl-(1 → 3)]-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl ester; 3-O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosylzanhic acid 28-O-β-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl ester; 3-O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosylmedicagenic acid 28-O-β-D-xylopyranosyl-(1 → 4)-[α-L-arabinopyranosyl-(1 → 3)]-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl ester and 3-O-β-D-glucopyranosylmedicagenic acid 28-O-β-D-xylopyranosyl-(1 → 4)-[α-L-arabinopyranosyl-(1 → 3)]-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl ester. The specific saponins synthesized by M. marina may have a role in its tolerance to environment, representing a reservoir of osmolytic sugars

    Isolated eustachian tube osteoma: Common lesion in uncommon site

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    Isolated Eustachian tube osteomata are a very rare entity indeed, with the last case being reported in 1979. We describe a case of the otoscopic finding of a blue-yellowish eardrum and successive identification by computed tomography scan of an osteoma localized in the Eustachian tube. Clinical presentation and diagnostic and therapeutic phases in comparison with the literature will be discussed
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