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Cytoplasmic Processes (cytoplasmic + process)
Selected AbstractsNodular fasciitis of parotid region: A pitfall in the diagnosis of pleomorphic adenomas on fine-needle aspiration cytologyDIAGNOSTIC CYTOPATHOLOGY, Issue 3 2005Ph.D., Reda S. Saad M.D. Abstract Fine-needle aspiration cytology (FNAC) is routinely employed for the preoperative diagnosis of salivary gland lesions. Although most cases show morphologic features characteristic of specific entities, some lesions can be diagnostically challenging. We report two parotid aspirates, initially diagnosed as pleomorphic adenoma on FNA. The patients, a 33-yr-old white man, and a 24-yr-old white woman, presented with indurated lesions arising in the parotid gland region. The aspirates from both patients were markedly hypercellular. Smears showed a mixture of spindle cells with a well-demarcated cytoplasm showing occasional long cytoplasmic process; and cells with abundant cytoplasm with round to oval eccentric nuclei, giving the impression of plasmacytoid cells of pleomorphic adenoma. The nuclear chromatin was evenly distributed and finely granular with one or two occasional small nucleoli. Intermingled with the tumor cells were scattered neutrophils, eosinophils, and macrophages. Aggregates of spindle cells were also seen embedded in a mucoid background with occasional small tufts of a fibrillar mucoid stroma. These fibrillar tufts were magenta red in the Diff-Quik stain, giving the impression of matrix of pleomorphic adenoma. Both cases were later diagnosed on histologic examination as nodular fasciitis. Nodular fasciitis should be considered in the differential diagnosis of a mass arising in association with the parotid gland. Diagn. Cytopathol. 2005;33:191,194. © 2005 Wiley-Liss, Inc. [source] Soft-tissue perineurioma in a 20-year-old patient with neurofibromatosis type 1 (NF1): report of a case and review of the literatureJOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2007Gregory G. Ausmus Background:, Perineurioma is a rare benign soft-tissue tumor composed of cells showing differentiation toward the perineurial cells of the nerve sheath. Although mutations in the neurofibromatosis 2 (NF2) gene have been documented in this tumor, there is no known association between perineuriomas and type 1 or 2 NF. Methods:, This is the first report of a case of soft-tissue perineurioma occurring in a patient with NF1. Results:, Histopathologic examination revealed a 2.0-cm well-circumscribed, spindle-cell neoplasm with slender, elongated, bipolar, wavy cytoplasmic processes and wavy, elongated nuclei in a hyalinized stroma with focal myxoid areas. The architecture was composed predominantly of short fascicles with areas exhibiting a storiform pattern. Immunohistochemistry showed positive labeling for epithelial membrane antigen (EMA) but no staining for S-100 and smooth muscle actin (SMA). Conclusion:, This case illustrates that perineurioma can occur in association with NF1. Perineuriomas can be confused with other spindle-cell neoplasms, and relevant features and immunohistochemistry of these lesions are outlined. The patient has not had a recurrence with limited follow-up. [source] An Insight to Pituitary Folliculo-Stellate CellsJOURNAL OF NEUROENDOCRINOLOGY, Issue 6 2008S. Devnath Folliculo-stellate cells (FS-cells) are star-shaped and follicle-forming cells in the anterior pituitary gland that were first identified by electron microscopy as non-endocrine agranular cells. Light microscopy has revealed many of their cytophysiological features and the FS-cell is known to be positive for S-100 protein, a marker for FS-cells. So far, functions ascribed to FS-cells include the formation of an extensive and complex tridimentional network, scavenger activity by engulfing degenerated cells, paracrine regulation of endocrine cells by producing various growth factors and cytokines, such as interleukin-6, leukemia inhibitory factor, basic fibroblastic growth factor, vascular endothelial cell growth factor and follistatin, and large-scale inter-cellular communication by means of their long cytoplasmic processes and gap junctions. Moreover, their multi-potential characteristics and other cytological features support the possibility of them becoming organ-specific stem cells. This concept is yet to be resolved, however. In this review, we focus on these features of FS-cells along with some futuristic approaches. [source] Astrocytic hypertrophy in dysmyelination influences the diffusion anisotropy of white matterJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2007Laura A. Harsan Abstract The effect of a proteolipid protein (PLP) mutation on the developing white matter anisotropy was examined by diffusion tensor magnetic resonance imaging (DT-MRI) in a noninvasive study of a mouse model of Pelizaeus-Merzbacher disease (PMD). The jimpy PLP mutation in mice produces an irreversible dysmyelination in jimpy males, whereas heterozygous females exhibit a transient hypomyelination, as assessed by a longitudinal study of the same mice during development. Modifications of the different individual DT-MRI parameters were highlighted by specific changes in tissue structures caused by the mutation that includes the hypomyelination, axonal abnormalities, and recovery. Astrocytic hypertrophy is a striking cellular event in dysmyelinated jimpy brain, where most axons or bundles of fibers are entirely wrapped by astrocyte cytoplasmic processes, so its influences on DT-MRI parameters in dysmyelination were examined for the first time. DT-MRI data of the jimpy brain were compared with those obtained from dysmyelination of (oligo-TTK) transgenic mice, induced by oligodendrocyte killing, which have a mild astrocyte hypertrophy (Jalabi et al., 2005), and from recovering jimpy females, which have reduced astrocyte hypertrophy. The unique morphological feature of astrocytes in jimpy males coupled with an increase in the water channel protein aquaporin 4 (AQP4) was found to facilitate the directional water diffusion in the white matter. In addition to the major changes of DT-MRI parameters in the two dysmyelinated mice caused by the myelin loss and axonal modifications, the amplified magnitude of radial and axial diffusions in jimpy males was attributed principally to the strongly pronounced astrocyte hypertrophy. © 2007 Wiley-Liss, Inc. [source] Malignant peripheral nerve sheath tumor of the uterine cervix expressing both S-100 protein and HMB-45JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 6 2009Na Rae Kim Abstract A 50-year-old woman presented with a large cervical polypoid mass. Grossly, the mass occupied a substantial proportion of the cervical canal, measuring 6 cm. Histologically, the mass showed a spindle cell malignancy arranged in large fascicles that penetrated deeply into the fibromuscular wall of the cervix. The spindle cells were immunoreactive for both S-100 protein and HMB-45 antigen, but were negative for Melan-A. Electron microscopy showed that cytoplasmic processes of the spindle to oval tumor cells contained microtubules and were lined by basal lamina and abundant intercellular collagen spacing with no melanosomes in any stage. As far as we are aware, this is the ninth reported case of cervical malignant peripheral nerve sheath tumor (MPNST), and the second reported case of MPNST expressing HMB-45 antigen. [source] Functional Morphology of Equine Pre-ovulatory Cumulus-oocyte ComplexesANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005S. Kölle Knowledge of the functional morphology of equine cumulus-oocyte-complexes (COCs) shortly before ovulation is scarce. Therefore the aim of our studies was to characterize COCs matured in vivo by light microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and immunohistochemistry (ICC). Pre-ovulatory COCs were obtained by ultrasound-guided transvaginal aspiration of pre-ovulatory follicles of 26 pony mares. The morphology of pre-ovulatory COCs was compared to that of immature COCs obtained by slicing of ovaries from the slaughterhouse. As shown by light microscopy and SEM, immature COCs possess numerous round, densely packed cumulus cells, which contact each other and possess merely single short processes. Contrary, in pre-ovulatory oocytes the cumulus cells are widely separated but send long cytoplasmic processes to the zona pellucida (ZP). All the cumulus cells are embedded in a huge amount of homogenous extracellular matrix. As shown by alcian blue staining and Periodic Acid Schiff Reaction (PAS) with and without amylase digestion, this matrix contains glycoproteins and acidic and sulphated glycosaminoglycans. In pre-ovulatory COCs both the oocyte and the cumulus cells produce glycosaminoglycans, whereas immature COCs are negative for alcian blue. Similarly, glycoproteins are synthesized in pre-ovulatory, but not in immature COCs. As shown by ICC, hyaluronic acid is one of the most abundant mucopolysaccharide in the pre-ovulatory COC. The high synthetic activity of the cumulus cells in the pre-ovulatory COC is confirmed by TEM showing densely packed endoplasmic reticulum (ER) and accumulation of glycogen in the cumulus cells. Our results imply that in the equine in vitro maturation of the oocyte is characterized by the cumulus cells synthesizing an extracellular matrix of glycoproteins and acidic and sulphated glycosaminoglycans. The extensive production of extracellular, water-binding matrix in the pre-ovulatory COC ensures mechanical protection and nutrition of the oocyte. [source] Vitreous surgery for macular hole in patients with Vogt-Koyanagi-Harada diseaseCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 9 2008Izumi Kobayashi MD Abstract We describe two patients with Vogt-Koyanagi-Harada (VKH) disease, both in the convalescent stage, who presented with unilateral macular holes together with clinically significant epi-retinal membranes. Vitreo-retinal surgery was performed on the affected eyes and the surgical technique involved a standard three-port vitrectomy, peeling of the epi-retinal and internal limiting membrane (ILM). In both cases the retinae were tamponaded with air resulting in anatomical closure of the macular holes. The histology of the excised membrane was available in one case and this revealed multiple layers of presumed retinal pigment epithelial cells with cytoplasmic processes and intercellular junctions forming a basal lamina attached to the smooth surface of the ILM. Our findings demonstrate that macular holes can develop in patients with VKH but that the hole can be successfully closed with vitreo-retinal surgery. The convalescent stage tends to occur several weeks after the acute stage when the uveitic process has subsided and is characterized by choroidal depigmentation, producing a sunset glow appearance to the ocular fundus. Patients may also demonstrate varying degrees of cutaneous hypopigmentation, poliosis and/or alopecia. Macular holes have also been reported previously in patients during the convalescent stage of VKH and this communication describes the outcome of two patients who underwent vitreo-retinal surgery for this problem. [source] | |||||||||||||