121 research outputs found

    The Relation Between Pseudopregnancy and the Chemical Induction by Four Carcinogens of Mammary and Ovarian Tumours in BALB/c Mice

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    did not occur in BALB/c virgin or lobectomised female mice following skin application of 20-methylcholanthrene (MC) for a limited period of 12 weeks. Virgin BALB/c mice, even when caged 5 in a box, rarely undergo pseudopregnancy (Caschera, 1960) and do so less frequently when the olfactory lobes have been removed. By rendering BALB/c mice artificially pseudopregnant the incidence of mammary tumours following MC treatment was 44 per cent. Marked differences were observed in the structure of the unaffected breasts, uteri and ovaries in non-pseudopregnant and pseudopregnant mice, and thus it was concluded that the hormonal conditions of pseudopregnancy were requisite for the development of mammary cancer following limited chemical treatment of the strain. Ovarian tumours did not occur in any of the groups. Bonser (1958) observed that a limited dose by skin application of the four carcinogens 9,10-dimethyl-1,2-benzanthracene (DMBA), MC, 1,2: 5,6-dibenzanthracene (DBA) and 3,4-benzopyrene (BP) induced mammary tumours in virgin IF mice; Biancifiori, Bonser and Caschera (1961) obtained a similar result i

    Comparison of intrascalar location of straight vs perimodiolar electrode array by flat-panel computerized tomography

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    Introduction, One of the fields of technological advancement in cochlear implants (CI) pursued by all manufacturers is the development of less traumatic electrodes that can conform to the anatomy of the cochlea, and possibly enhance the outcomes. Recently, a slim precurved perimodiolar electrode with an insertion guidance sleeve has been designed in order to facilitate the insertion and to avoid the inter-scalar dislodgement that frequently occurs at the first basal turn. Aim of this study was to evaluate the intracochlear position of different Nucleus electrode arrays in aduld and pediatric CI recipients by means of flat-panel volume computerized tomography (FPCT). Methods, Fifty-six CI recipients (37 females, 19 males), 1 to 80 years of age, operated by the same surgeon with the same technique, were included. All underwent FPCT with a C-arm angiographic system including a digital flat panel detector 30 x 40 cm, with a source-to-image-receptor distance of 120cm. The imaging assessment was performed the day after surgery in all cases. Sequential and simultaneous CI were included and a total of 68 ears have been analyzed. The primary objective was to identify the scalar location of the array (completely in scala tympani vs. partially dislodged in scala vestibuli) and the site of dislocation. Secondarily, we measured the medial-lateral position within the scala, the insertion depth (mm and angles). The FPCT findings were also contrasted with the type of cochleostomy (round window (RW), extended RW, promontorial) and with the residual hearing preservation. Results, Fifty-nine ears were implanted with a perimodiolar electrode, either Nucleus CI532 (n=45) or a CI412 / CI512 Contour Advance (n=14), while 9 received a straight one (Nucleus CI422/CI522). A RW approach was performed more frequently (41 out of 45 = 91.1 %) with CI532 than with the other arrays (10 out of 23 = 43.5%). Inferior and/or anterior cochleostomy were never performed. The CI532 showed the most consistent and reliable intrascalar position, close to the modiolus and in the scala tympani. Scala vestibuli dislodgement was observed in (14.3%) of the Contour Advance electrodes and in (6.7%) of the CI532. Pre-operative residual hearing was preserved within 10 dB HL in 62% of the cases. Conclusions: the CI532 electrode array achieved the most consistent and reliable perimodiolar location by FPCT; in our small series it appeared to be dislodged in the scala tympani in the minority of cases

    MR Imaging in Menière Disease: Is the Contact between the Vestibular Endolymphatic Space and the Oval Window a Reliable Biomarker?

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    BACKGROUND AND PURPOSE: No reliable MR imaging marker for the diagnosis of Meniere disease has been reported. Our aim was to investigate whether the obliteration of the inferior portion of the vestibule and the contact with the stapes footplate by the vestibular endolymphatic space are reliable MR imaging markers in the diagnosis of Meniere disease. MATERIALS AND METHODS: We retrospectively enrolled 49 patients, 24 affected by unilateral sudden hearing loss and 25 affected by definite Meniere disease, who had undergone a 4-hour delayed 3D-FLAIR sequence. Two readers analyzed the MR images investigating whether the vestibular endolymphatic space bulged in the third inferior portion of the vestibule contacting the stapes footplate. This sign was defined as the vestibular endolymphatic space contacting the oval window. RESULTS: We analyzed 98 ears: 27 affected by Meniere disease, 24 affected by sudden sensorineural hearing loss, and 47 that were healthy. The vestibular endolymphatic space contacting the oval window showed an almost perfect interobserver agreement (Cohen κ = 0.87; 95% CI, 0.69–1). The vestibular endolymphatic space contacting oval window showed the following: sensitivity = 81%, specificity = 96%, positive predictive value = 88%, and negative predictive value = 93% in differentiating Meniere disease ears from other ears. The vestibular endolymphatic space contacting the oval window showed the following: sensitivity = 81%, specificity = 96%, positive predictive value = 96%, negative predictive value = 82% in differentiating Meniere disease ears from sudden sensorineural hearing loss ears. CONCLUSIONS: The vestibular endolymphatic space contacting the oval window has high specificity and positive predictive value in differentiating Meniere disease ears from other ears, thus resulting in a valid tool for ruling in Meniere disease in patients with mimicking symptoms

    Transport of Live Cells under Sterile Conditions Using a Chemotactic Droplet

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    © 2018 The Author(s). 1-Decanol droplets, formed in an aqueous medium containing decanoate at high pH, become chemotactic when a chemical gradient is placed in the external aqueous environment. We investigated if such droplets can be used as transporters for living cells. We developed a partially hydrophobic alginate capsule as a protective unit that can be precisely placed in a droplet and transported along chemical gradients. Once the droplets with cargo reached a defined final destination, the association of the alginate capsule and decanol droplet was disrupted and cargo deposited. Both Escherichia coli and Bacillus subtilis cells survived and proliferated after transport even though transport occurred under harsh and sterile conditions

    Involvement of the spinal cord in primary mitochondrial disorders : a neuroimaging mimicker of inflammation and ischemia in children

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    CITATION: Alves, C. A. P. F. et al. 2021 . Involvement of the spinal cord in primary mitochondrial disorders : a neuroimaging mimicker of inflammation and ischemia in children. American Journal of Neuroradiology, 42(2):389-396, doi: 10.3174/ajnr.A6910.The original publication is available at: https://pubmed.ncbi.nlm.nih.govBackground and purpose: Little is known about imaging features of spinal cord lesions in mitochondrial disorders. The aim of this research was to assess the frequency, imaging features, and pathogenic variants causing primary mitochondrial disease in children with spinal cord lesions. Materials and methods: This retrospective analysis included patients seen at Children's Hospital of Philadelphia between 2000 and 2019 who had a confirmed diagnosis of a primary (genetic-based) mitochondrial disease and available MR imaging of the spine. The MR imaging included at least both sagittal and axial fast spin-echo T2-weighted images. Spine images were independently reviewed by 2 neuroradiologists. Location and imaging features of spinal cord lesions were correlated and tested using the Fisher exact test. Results: Of 119 children with primary mitochondrial disease in whom MR imaging was available, only 33 of 119 (28%) had available spine imaging for reanalysis. Nineteen of these 33 individuals (58%) had evidence of spinal cord lesions. Two main patterns of spinal cord lesions were identified: group A (12/19; 63%) had white ± gray matter involvement, and group B (7/19; 37%) had isolated gray matter involvement. Group A spinal cord lesions were similar to those seen in patients with neuromyelitis optica spectrum disorder, multiple sclerosis, anti-myelin oligodendrocyte glycoprotein-IgG antibody disease, and leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation. Group B patients had spinal cord findings similar to those that occur with ischemia and viral infections. Significant associations were seen between the pattern of lesions (group A versus group B) and the location of lesions in cervical versus thoracolumbar segments, respectively (P < .01). Conclusions: Spinal cord lesions are frequently observed in children with primary mitochondrial disease and may mimic more common causes such as demyelination and ischemia.Publisher's versio
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