Search results for "Microscopy"
showing 10 items of 3390 documents
Nonceliac wheat sensitivity in the context of multiple food hypersensitivity: new data from confocal endomicroscopy.
2015
Dear Editor, We enjoyed reading the article by Fritscher-Ravens et al who showed, by confocal endomicroscopy, that candidate food antigens caused immediate duodenal mucosa damage in irritable bowel syndrome (IBS) patients with a prolonged clinical history of symptoms after meals. Their in vivo data add evidence to the relationship between IBS and food allergy and seem to reinforce our hypothesis that a percentage of “nonceliac wheat sensitive” (NCWS) -patients with an IBS-like clinical presentation could suffer from non-immunoglobulin E-mediated wheat allergy. However, we would suggest that the very high percentage of positive confocal laser endomicroscopy patients (CLE) -22 out of 36- foun…
Expression of the Tumor Suppressor Gene Product p16INK4 in Benign and Malignant Melanocytic Lesions
1998
The gene MTS1 encodes p16INK4, an inhibitor of cyclin-dependent kinase 4, and is frequently deleted, mutated, or silenced by promoter methylation in melanoma cells and in the germline of familial melanoma patients. Although MTS1 may thus be the candidate melanoma suppressor gene that maps to chromosome 9p21, it is not clear how dysfunction at that locus temporally relates to melanoma progression. To further test its role in sporadic melanoma, the expression of p16INK4-protein and -mRNA was characterized in melanomas and melanocytic nevi by immunocytochemistry and in situ reverse transcriptase-polymerase chain reaction. Histologic tissue sections were immunolabeled with anti-p16INK4 antibody…
Clinicopathological and Immunohistochemical Study of Oral Amalgam Pigmentation
2012
Amalgam tattoo, the most common exogenous oral pigmentation, can sometimes be confused with melanotic lesions, being then biopsied. We present the clinicopathological characteristics of 6 biopsied cases (5 females and 1 male) of oral amalgam pigmentation. The most common location was the gingival mucosa, followed by the buccal and palatal mucosa. Morphology and distribution (stromal, perivascular, perineural, endomysial) of pigmentation was variable; there was only 1 case with fibrous capsular reaction and likewise only a single case of granulomatous foreign body reaction. Morphological variability is conditioned by the timing and amount of the pigment deposit, which is often associated wit…
Time sequence and site of fluid accumulation in experimental neurogenic pulmonary edema.
1976
The initial phase of pulmonary edema development following intracranial pressure elevation was studied by means of transmission electron microscopy. Using perfusion fixation and application of a blood tracer (HRP horseradish peroxidase) the time sequence and site of fluid leakage out of pulmonary vessels was demonstrated: - passage of edema fluid through intercellular clefts of alveolar capillary endothelium - edema accumulation in alveolar interstitial tissue - draining of edema fluid from the alveolar septum to the interstitium of terminal bronchioli and to lymphatic vessels. An early interepithelial fluid leakage out of the alveolar wall remains questionable.
Fine structural features of the cerebral microvasculature in hydrocephalic human infants: correlated clinical observations.
1989
Four of 30 human cerebral cortex biopsies from infants ranging from four days to about ten years treated for hydrocephalus by shunt operations are described paying special attention to the vascular structures. The biopsy specimens were studied in semi-thin and ultrathin sections. Attention is drawn to the role of pinocytotic vesicles found in capillaries and smaller vessels as a possible transcellular route for the hydrocephalic oedema resolution. No intercellular dehiscences or the so called blisters were observed. With the passage of time, the number of membrane bound vesicles increased and arrays of pinocytotic vesicles were discernible both on the abluminal as well as luminal aspect of …
Kinetics of Photofrin II in perifocal brain edema.
1993
Photodynamic therapy is under intense investigation as a possible adjuvant for the treatment of malignant tumors of the central nervous system. It relies on the fact that photosensitizers are selectively taken up or retained by malignant tissue. However, most brain tumors are accompanied by substantial vasogenic edema as a consequence of blood-brain barrier disruption within the tumor, leading to extravasation and propagation of plasma constituents into the surrounding brain tissue. Systemically administered photosensitizers may enter healthy tissue together with the edema fluid, possibly leading to sensitization of tissues outside the tumor. To test this hypothesis, vasogenic edema was ind…
Method for functional study of mitochondria in rat hypothalamus
2008
1872-678X (Electronic) Journal Article Research Support, Non-U.S. Gov't; Different roles of mitochondria in brain function according to brain area are now clearly emerging. Unfortunately, no technique is yet described to investigate mitochondria function in specific brain area. In this article, we provide a complete description of a procedure to analyze the mitochondrial function in rat brain biopsies. Our two-step method consists in a saponin permeabilization of fresh brain tissues in combination with high-resolution respirometry to acquire the integrated respiratory rate of the biopsy. In the first part, we carefully checked the mitochondria integrity after permeabilization, defined exper…
Species-specific effects of single sensillum ablation on mating position in Drosophila.
2003
0022-0949 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; Dipteran insects show a wide range of species-specific mating positions. Interspecific transitions from one position to another may reflect sexual or natural selection, or be pleiotropic consequences of other genetic changes. Like many cyclorrhaphan flies, Drosophila species mate with the male on the back of the female, positioned centrally. Mechanosensory sensilla on the male genitalia of three species of the melanogaster species sub-group of Drosophila have species-specific effects on mating position and on courtship success: ablation of a single pair of bristles on the genital claspers of D. melanogaste…
Virus-like particles, bacteria and microsporidia affect spindle-associated membranes in spermatocytes of Lepidoptera species.
1997
SummaryLarval testes of four Lepidoptera species were examined using electron microscopy. The testes of one species, the Mediterranean mealmothEphestia kuehniella(Pyralidae), were devoid of intracellular pathogens and serve as a control. In this species, metaphase spindles of primary spermatocytes showed a thick layer of perispindle membranes. The membranes were structurally very similar to the agranular endoplasmic reticulum. Membranes of this type occurred also at high frequency throughout the spindle matrix. The analysis of larval testes ofPieris brassicae(Pieridae) revealed virus-like particles within spermatocytes. In another species,Philudoria potatoria(Lasiocampidae), the spermatocyt…
Structural characterization and primary in vitro cell culture of locust male germline stem cells and their niche
2011
AbstractThe establishment of in vitro culture systems to expand stem cells and to elucidate the niche/stem cell interaction is among the most sought-after culture systems of our time. To further investigate niche/stem cell interactions, we evaluated in vitro cultures of isolated intact male germline–niche complexes (i.e., apical complexes), complexes with empty niche spaces, and completely empty niches (i.e., isolated apical cells) from the testes of Locusta migratoria and the interaction of these complexes with isolated germline stem cells, spermatogonia (of transit-amplifying stages), cyst progenitor cells, cyst progenitor cell-like cells, cyst cells, and follicle envelope cells. The stru…