171,032 research outputs found
COMPUTED TOMOGRAPHIC CHARACTERISTICS OF THE CISTERNA CHYLI IN DOGS
No full textPrevious lymphangiographic studies have investigated the use of computed tomography (CT) for characterizing the thoracic duct and its tributaries in dogs. However, there is limited published information on the appearance of the canine cisterna chyli using CT. The objective of this retrospective study was to describe the features of the canine cisterna chyli in pre- and post-contrast abdominal CT studies. The presence, location, shape, maximum width, size compared with the aortic diameter (Ao:cisterna chyli ratio) and mean attenuation of the cisterna chyli were recorded from archived abdominal CT scans of 30 dogs. Breed, age, sex and neutering status were also noted. A cisterna chyli was identified in 26 of the dogs (87%). In 22 cases a cisterna chyli could be reliably identified prior to intravenous contrast administration and in all 26 cases in postcontrast images. The cisterna chyli was most commonly located right dorsolateral to the abdominal aorta between L1 and L4. Shape varied on transverse images from crescent-like to globular and maximum diameters ranged from 5 to 9 mm. The Ao:cisterna chyli ratio varied between 0.29 and 0.71 (mean valuemales: 0.32; females: 0.38). On pre-contrast images the mean Hounsfield units were 21.3HU (range: -3.8 to 64.25). Mild enhancement of the cisterna chyli post-contrast was observed in 24 dogs (80%). Findings supported the use of pre- and post-contrast abdominal CT as a non-invasive method for assessing qualitative and quantitative characteristics of the canine cisterna chyli. (C) 2013 American College of Veterinary Radiology.</p
Ultrastructural features of skeletal muscle in adult and aging Ts65Dn mice, a murine model of Down syndrome.
No full textPatients with Down syndrome (DS) suffer from muscle hypotonia and an altered motor coordination whose basic mechanisms are still largely unknown. Interestingly, they show muscle weakness like healthy aged subjects, suggesting possible similarity with sarcopenia: to test this hypothesis, the Ts65Dn mouse, a suitable animal model of DS, was employed. The fine structure of skeletal fibres of the quadriceps femoris muscle was analysed in adult (12 months) and aging (19 months) animals and their age-matched euploid controls by combining morphometry and immunocytochemistry at transmission electron microscopy. Results demonstrated structural alterations of mitochondria and myonuclei reminiscent of those observed in age-related sarcopenia, supporting the hypothesis that trisomy leads to an early aging of skeletal muscle consistent with the multi-systemic premature aging typical of DS
Simultaneous ultrastructural analysis of fluorochrome-photoconverted diaminobenzidine and gold immunolabelling in cultured cells
No full textDiaminobenzidine photoconversion is a technique by which a fluorescent dye is transformed into a stably insoluble, brown, electrondense signal, thus enabling examination at both bright field light microscopy and transmission electron microscopy. In this work, a procedure is proposed for combining photoconversion and immunoelectron microscopy: in vitro cell cultures have been first submitted to photoconversion to analyse the intracellular fate of either fluorescent nanoparticles or photosensitizing molecules, then processed for transmission electron microscopy; different fixative solutions and embedding media have been used, and the ultrathin sections were finally submitted to post-embedding immunogold cytochemistry. Under all conditions the photoconversion reaction product and the target antigen were properly detected in the same section; Epon-embedded, osmicated samples required a pre-treatment with sodium metaperiodate to unmask the antigenic sites. This simple and reliable procedure exploits a single sample to simultaneously localise the photoconversion product and a variety of antigens allowing a specific identification of subcellular organelles at the ultrastructural level
Ultrastructural and immunocytochemical study of skeletal muscles in a murine model of Down syndrome
No full textDown syndrome (DS) is a genetically-based disease which, in humans, affects about 1 over 700 newborns and is due to the presence of all or part of an extra chromosome 21. Among their several pathological traits, DS subjects suffer from an altered motor coordination but, although these difficulties in motility represent a serious problem in daily life, scarce data exist in the literature on skeletal muscles in DS. This is likely due to the obvious difficulties in obtaining bioptic material from patients with DS; however, this limitation may be partly overcome using suitable animal models. The Ts65Dn mouse bearing a trisomy for a segment of chromosome 16 (i.e. the homologue of human chromosome 21) is the most extensively studied murine model of DS since displays a remarkable number of phenotypic traits expressed in the human condition, including motor dysfunctions. By combining morphometry and immunocytochemistry at transmission electron microscopy, we examined the fine structure of skeletal myofibres, with particular attention to myonuclei, in adult and late adult Ts65Dn mice and their age-matched euploid controls, with the aim to evaluate the combined effect of DS and age on skeletal muscle. Our observations demonstrated in Ts65Dn mice an irregular arrangement of myofibrils and structural alterations of mitochondria, which often occurred in large clusters instead of being lined between myofibrils. In addition, myonuclei showed morphological modifications and changes in the amount of factors involved in RNA processing
Simultaneous ultrastructural analysis of fluorochrome-photoconverted diaminobenzidine and gold immunolabeling in cultured cells.
No full textDiaminobenzidine photoconversion is a technique by which a fluorescent dye is transformed into a stably insoluble, brown, electrondense signal, thus enabling examination at both bright field light microscopy and transmission electron microscopy. In this work, a procedure is proposed for combining photoconversion and immunoelectron microscopy: in vitro cell cultures have been first submitted to photoconversion to analyse the intracellular fate of either fluorescent nanoparticles or photosensitizing molecules, then processed for transmission electron microscopy; different fixative solutions and embedding media have been used, and the ultrathin sections were finally submitted to post-embedding immunogold cytochemistry. Under all conditions the photoconversion reaction product and the target antigen were properly detected in the same section; Epon-embedded, osmicated samples required a pre-treatment with sodium metaperiodate to unmask the antigenic sites. This simple and reliable procedure exploits a single sample to simultaneously localise the photoconversion product and a variety of antigens allowing a specific identification of subcellular organelles at the ultrastructural level
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Populonia, acropoli: un deposito rituale dalla cisterna pubblica
No full textNel lavoro si presenta lo studio dei resti animali rinvenuti all'interno di uno dei vani orientali di un edificio posto sull’acropoli di Populonia. I resti, riferibili a un rito o pasto sacrificale, erano contenuti in un piatto a vernice nera. Tali resti, costituiti quasi esclusivamente da materiale osteologico riferibile a suini e sono da riferire ad almeno sei individui che non avevano ancora raggiunto la piena maturità. Il rituale sembra da connettere con l'impianto di una grande cisterna
Ultrastructural analyses on tissues from mice fed on genetically modified soybean
No full textThe work describes the ultrastructural features of tissues from mice fed on genetically modified soybea
Interaction of GFP-SCs with myelin and astrocytes after delivery in the cisterna magna or the spinal cord parenchyma.
No full text<p>Combined detection of MOG, GFAP and GFP on cryostat sections showed that GFP-SCs grafted in the cisterna magna (A, D) or the spinal cord (B,C, E, F) are found in demyelinated lesions (delineated by dashed lines) detected by MOG immunostaining (red) both after 7 days (B) and 21 days (A, C) after delivery. GFAP+ astrocytes (blue) interact with GFP-labeled SCs in the cisterna magna (D) and the spinal cord (E, F); 7 days (E) or 21 days (F) after spinal cord graft or 21 days after cisterna magna graft (D).</p
Dilated cisterna chyli
No full textA 46-year-old man was referred to our department because of chronic low back pain. A magnetic resonance (MR) examination of the spine revealed bilateral spondylolysis at the level of the lumbar vertebra L4, with associated anterolisthesis as well as degenerative disk disease at L4-L5. Additionally an oval-shaped hypointense structure was seen in the prevertebral space extending from the L1-L2 to L2-L3 level (arrows) on sagittal T1-weighted MR imaging (Fig. A). Axial T2-weighted MR imaging with a HASTE sequence showed a well delineated structure (arrow) adjacent and to the right of the abdominal aorta (Fig. B). The location, shape and fluid content were consistent with a focal dilatation of the cisterna chyli. Conservative therapy for low back pain was initiated. Because of the benign nature of the prevertebral structure, no further therapy was required
- …
