Search results for "Ultrastructure"

Fine Structure of Antennal Sensilla of Paysandisia archon and Electrophysiological Responses to Volatile Compounds Associated with Host Palms

2014

Paysandisia archon (Lepidoptera: Castniidae) is a serious pest of palm trees. A comprehensive knowledge of the insect olfactory system is essential for the development of efficient semiochemical-based control methods. The olfactory sensilla are located particularly on the antennae, and these can detect plant volatiles that provide important cues for the insects in the search for their host plants. To date, the fine structure of P. archon antennal sensilla studies and their role in host-plant perception have not been investigated in great detail. Using light microscopy and scanning and transmission electron microscopy, the antennae of both sexes of P. archon are described here in detail, acc…

Ultramicro-trauma in the endometrial-myometrial junctional zone and pale cell migration in adenomyosis

2015

Objective To determine if ultrastructural tissue trauma occurs in the junctional zone in uteri in adenomyosis. Design A case-control experimental study. Setting Endometriosis research center. Patient(s) Twelve uteri with adenomyosis, and 9 uteri without adenomyosis, were gained during laparoscopy-assisted vaginal hysterectomy. Intervention(s) Transmission electron microscopic study of the junctional zone, as well as immunohistochemical staining for epithelial cadherin, and van Gieson staining and immunofluorescence for CD45 and CD68. Main Outcome Measure(s) Analysis of the electron microscopy photos and the immunoreactive scores of the staining. Result(s) The inner myometrial muscle fibers …

Ultrastructure of one Ewing's sarcoma of bone with endothelial character and a comparative review of the vessels in 27 cases of typical Ewing's sarco…

1980

An atypical variant of Ewing's sarcoma, located in the left hip of a nine-year-old girl, is discussed at optical, histochemical and electron microscopical level. The endothelial appearing cells seem to play a main role in its histogenesis. Tumoral cells of an undifferentiated blastemic nature show round nuclei and bright lucent cytoplasm, being organized in solid sheets or vascular-like profiles. Alkaline and acid phosphatases are very prominent in all tumoral cells, and some of them also show PAS positive material. Its ultrastructure demonstrates an active pinocytic capacity, cytoplasmic filaments and Weibel-Palade bodies. Simultaneously a review is performed on 27 cases of typical Ewing's…

Psammous desmo-osteoblastoma

1987

Fibro-osteo-cemental lesions of the jaw bones are a heterogeneous group of diseases which present problems in classification. Psammous desmo-osteoblastoma is one of four newly proposed entities (Makek 1983) and has until now been characterized by its light microscopic, clinical and radiological features. On electron microscopy this tumour exhibits fibroblastic (preosteoblastic), osteoblastic and osteocytic cells and a globular mineralization unlike the mineralization of the psammoma bodies. Immunohistological investigations with anti-osteonectin, a bone specific protein linking mineral to collagen, showed positive intracellular staining in all tumour cells and extracellular staining in the …

Comparative Ultrastructure of Wild-Type and Tumorous Cells of Drosophila

1984

In Drosophila genetic factors cause malignant and benign neoplasms (Gateff, 1978a,b,c). In addition, compactly growing lethal tumors have been obtained from eye-antennal imaginal discs during serial subculture in the abdomens of female flies (Gateff, 1978a,b). The following tumor types have been found: (1) lethal-benign imaginal disc neoplasms, (2) malignant neuroblastomas, (3) malignant blood cell neoplasms, and (4) a benign gonial cell neoplasm. The fine structure of some of the above tumors has been studied and compared to the fine structure of corresponding wild-type cells. These will be discussed below.

Ultrastructural localization of Ca2(+)-binding sites in the middle ear mucosa of the rat.

1990

Cations were precipitated with potassium-pyroantimonate in the middle ear mucosa of the rat and the distribution of the formed precipitates was studied by electron microscopy. The precipitate density in various cells of the different epithelia of the middle ear mucosa was determined on electron micrographs by counting the number of precipitates per unit area. Electron spectroscopic imaging was also performed to obtain information about the spatial distribution of the precipitates and their elemental composition.

Ultrastructural Lesion in Autoimmune Hepatitis and Steps of the Immune Response in Liver Tissue

1991

Alport's syndrome: specificity and pathogenesis of glomerular basement membrane alterations.

1987

In Alport's syndrome (AS) thinning and splitting of the glomerular basement membrane (GBM) are assumed to be characteristic ultrastructural alterations. Both lesions are, however, non-specific because they can occur in other glomerulopathies. In addition, splitting may be found in non-glomerular structures. It should be emphasized that the characteristic lesion in AS is a result of the widespread combination of thin and split GBM in the same biopsy specimen. In our opinion the basic lesion is the thin GBM, which is characterized by a lamina densa (measuring 50-150 nm in thickness) which may begin to split as a result of focal detachment of podocyte pedicles (spacing) and repeated subepithel…

Electron microscopic studies on skin and lymphocytes in early juvenile neuronal ceroid-lipofuscinosis.

1987

Skin and lymphocytes of three patients with early juvenile neuronal ceroid-lipofuscinosis (NCL) were ultras trueturally investigated. Fingerprint profiles (FPP), isolated and I or mixed with curvilinear profiles (CLP), in various dermal cells and large, usually single lipopigments delineated by a trilaminar membrane and filled with a granular matrix, FPP and occasionally lipid droplets in lymphocytes were observed in all three patients. Characteristic lipopigments in lymphocytes are an important feature to differentiate between early juvenile NCL and late infantile and juvenile NCL.

HMB-45 Immunostaining and Ultrastructure of Melanocytic Hyperplasia in Pigmented Basal Cell Carcinomas

1999

The pigmented variant of basal cell carcinoma (PBCC) may be clinically misinterpreted as malignant melanoma. Histologically this variant is characterized by the presence of functional melanocytes distributed among epithelial tumor cells, particularly in superficial areas. Our finding of a case of PBCC with numerous atypical HMB-45-positive melanocytes prompted us to analyze the morphologic and immunohistochemical features of 20 consecutive cases of PBCC. Four additional cases with numerous large HMB-45-positive melanocytes, also present in the most invasive tumor nests, were found. Ultrastructural examination was performed in two selected cases. Large melanocytes with immature (stages I an…