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Large Cells (large + cell)
Terms modified by Large Cells Selected AbstractsDevelopmental patterns of the hermaphroditic gonad in dicyemid mesozoans (Phylum Dicyemida)INVERTEBRATE BIOLOGY, Issue 4 2007Hidetaka Furuya Abstract. The development of the hermaphroditic gonad, the infusorigen, was studied in fixed specimens of 16 species belonging to four genera (Conocyema, Dicyema, Dicyemennea, and Pseudicyema) of dicyemid mesozoans. In addition, the literature on the cell lineages of infusorigens of eight other species was reviewed. After an agamete (axoblast) undergoes an unequal first division, excluding a small cell (the paranucleus), the resulting large cell divides to form the infusorigen. Five infursorigen cell lineage patterns can be identified: type I, both the first oogonium and the first spermatogonium are produced at the third division; type II, the first spermatogonium is produced at the second division and the first oogonium is produced at the third division; type III, the first spermatogonium is produced at the second division and the first oogonium is produced at the fourth division; type IV, the first oogonium is produced at the second division and the first spermatogonium is produced at the third division; and type V, the first oogonium is produced at the second division and the first spermatogonium is produced at the fourth division. Later development is similar in members of all genera. Mature infusorigens are similarly organized in all species examined. Sizes of agametes and infusorigen axial cells, the number of infusorigens, and the type of reproductive strategy were not correlated with infusorigen developmental patterns or cell lineage patterns. [source] Spatial and temporal patterns of bone formation in ectopically pre-fabricated, autologous cell-based engineered bone flaps in rabbitsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2008Oliver Scheufler Abstract Biological substitutes for autologous bone flaps could be generated by combining flap pre-fabrication and bone tissue engineering concepts. Here, we investigated the pattern of neotissue formation within large pre-fabricated engineered bone flaps in rabbits. Bone marrow stromal cells from 12 New Zealand White rabbits were expanded and uniformly seeded in porous hydroxyapatite scaffolds (tapered cylinders, 10,20 mm diameter, 30 mm height) using a perfusion bioreactor. Autologous cell-scaffold constructs were wrapped in a panniculus carnosus flap, covered by a semipermeable membrane and ectopically implanted. Histological analysis, substantiated by magnetic resonance imaging (MRI) and micro-computerized tomography scans, indicated three distinct zones: an outer one, including bone tissue; a middle zone, formed by fibrous connective tissue; and a central zone, essentially necrotic. The depths of connective tissue and of bone ingrowth were consistent at different construct diameters and significantly increased from respectively 3.1 ± 0.7 mm and 1.0 ± 0.4 mm at 8 weeks to 3.7± 0.6 mm and 1.4 ± 0.6 mm at 12 weeks. Bone formation was found at a maximum depth of 1.8 mm after 12 weeks. Our findings indicate the feasibility of ectopic pre-fabrication of large cell-based engineered bone flaps and prompt for the implementation of strategies to improve construct vascularization, in order to possibly accelerate bone formation towards the core of the grafts. [source] Lymphomatoid Papulosis Presenting With B-Cell Lymphoma: A New Association?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Galan Lymphomatoid papulosis (LyP) is a cutaneous T-cell lymphoproliferative disorder, characterised by recurrent crops of necrotic self-healing papules and nodules. Although chronic, LyP typically has a benign clinical course in the majority of cases. Histologically, a malignant appearing T-cell lymphoid infiltrate is seen. The atypical cells often resemble the cerebriform cells of mycosis fungoides or Reed-Sternberg cells in Hodgkin lymphoma. Approximately 10,20% of the patients go on to develop lymphomas, including mycosis fungoides, CD30-positive anaplastic large cell and Hodgkin lymphoma. We report a case of LyP associated with a B-cell lymphoma. A 50-year-old male, presented with scattered erythematous scaly papules, some with central crust, located on the arms, trunk and leg of one-month duration. A skin biopsy revealed a polymorphous infiltrate with many large atypical lymphocytes, resembling Reed Sternberg cells. By immunohistochemistry, the large cells were positive for T-cell markers and CD30. Subsequently, he developed fever, night sweats and diffuse lymphadenopathy. A lymph node biopsy showed a vaguely nodular proliferation of small to medium lymphocytes. Immunophenotypic and flow cytometric studies best characterised the process as mantle cell lymphoma. Although, LyP has been previously associated with lymphomas of above-mentioned types, this is an extremely unusual case presenting with a low-grade B-cell lymphoma. [source] A case of anaplastic large cell lymphoma-induced hemophagocytic lymphohistiocytosis in an adolescent femalePEDIATRIC BLOOD & CANCER, Issue 7 2007Zdenka Krenova MD No abstract is available for this article. [source] Autodiffusion: a novel method for emitter formation in crystalline silicon thin-film solar cellsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 3 2007A. Wolf Abstract The in situ formation of an emitter in monocrystalline silicon thin-film solar cells by solid-state diffusion of dopants from the growth substrate during epitaxy is demonstrated. This approach, that we denote autodiffusion, combines the epitaxy and the diffusion into one single process. Layer-transfer with porous silicon (PSI process) is used to fabricate n-type silicon thin-film solar cells. The cells feature a boron emitter on the cell rear side that is formed by autodiffusion. The sheet resistance of this autodiffused emitter is 330,,/,. An independently confirmed conversion efficiency of (14·5,±,0·4)% with a high short circuit current density of (33·3,±,0·8) mA/cm2 is achieved for a 2,×,2,cm2 large cell with a thickness of (24,±,1) µm. Transferred n-type silicon thin films made from the same run as the cells show effective carrier lifetimes exceeding 13,µs. From these samples a bulk diffusion length L,>,111,µm is deduced. Amorphous silicon is used to passivate the rear surface of these samples after the layer-transfer resulting in a surface recombination velocity lower than 38,cm/s. Copyright © 2006 John Wiley & Sons, Ltd. [source] Radioembolization with selective internal radiation microspheres for neuroendocrine liver metastases,CANCER, Issue 5 2008Julie King MPH Abstract BACKGROUND. There are limited effective treatment options available and a poor 5-year survival for patients with inoperable neuroendocrine liver metastases (NETLMs). In this study, the authors prospectively assessed the safety and efficacy of treatment with yttrium 90 (90Y) radioactive microspheres for patients with unresectable NETLMs. METHODS. Radioactive 90Y resin microspheres (selective internal radiation [SIR-Spheres]) were administered through a temporarily placed percutaneous hepatic artery catheter concomitantly with a 7-day systemic infusion of 5-fluorouracil to patients with progressive, unresectable NETLMs. Patients were monitored prospectively, and the response to treatment was measured by using cancer markers and tumor size on computed tomography imaging studies. RESULTS. Thirty-four patients (22 men) with a mean age 61 years (range, 32-79 years) who had unresectable NETLMs were treated between December 2003 and December 2005. The mean (±standard error) follow-up was 35.2 ± 3.2 months. The site of the primary neuroendocrine tumor was the bronchus in 1 patient, the medullary thyroid in 2 patients, gastrointestinal in 15 patients, the pancreas in 8 patients, and of unknown origin in 8 patients. The tumors were classified as vipoma (1 tumor), somatostatinoma (1 tumor), glucagonoma (2 tumors), large cell (3 tumors), carcinoid (25 tumors), and of unknown origin (2 tumors). Complications after 90Y radioembolization included abdominal pain, which was mild to severe; nausea and fever; and lethargy that lasted from 1 week to 1 month. Two patients developed biopsy-proven radiation gastritis, 1 patient developed a duodenal ulcer, and there was 1 early death from liver dysfunction and pneumonia. Subjective changes from recorded baseline hormone symptoms were reported every 3 months. Symptomatic responses were observed in 18 of 33 patients (55%) at 3 months and in 16 of 32 patients (50%) at 6 months. Radiologic liver responses were observed in 50% of patients and included 6 (18%) complete responses and 11 (32%) partial responses, and the mean overall survival was 29.4 ± 3.4 months). In patients who had evaluable chromogranin A (CgA) marker levels, there was a fall in CgA marker levels after 90Y radioembolization in 19 patients (26%) at 1 month, in 19 patients (41%) at 3 months, in 15 patients (43%) at 6 months, in 11 patients (42%) at 12 months, in 8 patients (38%) at 24 months, and in 3 patients (46%) at 30 months. CONCLUSIONS. In this open study of 34 patients, the results demonstrated that radioembolization with 90Y resin microspheres can achieve relatively long-term responses in some patients with nonresectable NETLMs. Cancer 2008. © 2008 American Cancer Society. [source] Development of the pons in human fetusesCONGENITAL ANOMALIES, Issue 2 2007Toshihisa Hatta ABSTRACT Morphometric and histological studies of the pons were performed by light microscopy in 28 cases of externally normal human fetuses ranging from 90 to 246 mm in crown-rump length (CRL) and from 13 to 28 weeks of gestation. The brainstems of fetuses were embedded in celloidin or paraffin, and transverse sections were prepared. The pons was divided into two regions at the most ventral margin of the medial lemniscus at the level of the motor trigeminal nucleus. The relationships between the total dorsoventral length, ventral length, and dorsal length of the pons versus CRL and gestational ages were calculated, and empiric formulas were fitted. It was found that the ventral portion increased in size more rapidly than the dorsal portion. The proportion of the ventral portion in the total dorsoventral length was constitutively higher than that of the dorsal portion in the present range of CRL. In the pontine nuclei, from 235 mm in the CRL, some large cells with rich cytoplasm, pale nuclei, and a distinct nucleolus appeared on the dorsal side of the pyramidal tract. According to Weigert stained preparations, the first myelinated fibers in each motor root of the trigeminal, abducent, and facial nerves were recognized at 130,140 mm in CRL and the medial lemniscus at 230,235 mm. [source] Ultrastructural and histochemical study of the salivary glands of Aplysia depilans (Mollusca, Opisthobranchia)ACTA ZOOLOGICA, Issue 3 2001Alexandre Lobo-da-Cunha Abstract The digestive system of the sea hare, Aplysia depilans, includes a pair of ribbon-shaped salivary glands. A central duct and a large blood vessel run close to each other along the length of these glands and both are surrounded by a layer of muscle cells. Three cell types form the glandular epithelium: granular cells, vacuolated cells and mucocytes. The granular cells possess cilia and spherical secretion granules, located primarily in the apical region. The granules of immature cells have a low electron density and are mainly formed by neutral polysaccharides with small amounts of proteins. The granules of mature cells are larger, have a high electron density and are mainly formed by proteins with lower amounts of neutral polysaccharides. Transition stages between immature and mature granular cells are observed. The vacuolated cells are large and frequently pyramidal in shape, but after the application of histochemical techniques almost all vacuoles remain uncoloured. The numerous vacuoles contain flocculent material in a clear background and the mitochondria possess large crystalline structures in the matrix. A pyramidal shape is also typical of the mucocytes, which are filled with vesicles containing granular masses surrounded by a network of secretion material. These large cells are strongly stained by Alcian blue, revealing the presence of acidic mucopolysaccharides. This is the first ultrastructural study of the salivary glands in opisthobranch gastropods. [source] NGF and GDNF ameliorate the increase in ATF3 expression which occurs in dorsal root ganglion cells in response to peripheral nerve injuryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2004Sharon Averill Abstract Activating transcription factor-3 (ATF3) is a member of the ATF/CREB transcription factor superfamily and is induced in dorsal root ganglion (DRG) cells after nerve injury. In order to study the regulation of ATF3, we have examined the effect of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) on ATF3 expression. In untreated rats, sciatic nerve transection induced ATF3 immunoreactivity in 82% of L4 DRG cells at 14 days after axotomy. Intrathecal delivery of NGF or GDNF for 2 weeks commencing immediately after injury reduced the ATF3 expression to 35 and 23% of DRG cells, respectively. Cell size analysis indicated that NGF had protected a population of mainly small- to medium-sized cells, but that the GDNF had protected a population of both small and large cells. This effect was confirmed by double labelling for P2X3, CGRP and 200 kDa neurofilament, markers for small peptide-poor cells, peptide-rich cells and large cells, respectively. Thus GDNF reduced the percentage of ATF3-immunoreactive P2X3 cells from 70 to 4%, and the percentage of ATF3-immunoreactive neurofilament cells from 63 to 24%. NGF was less effective than GDNF in reducing ATF3 expression in these cell types, but reduced the percentage of ATF3-immunoreactive CGRP cells from 10% to <,1%. These results show that ATF3 expression in specific populations of DRG cells can be modulated by exogenous supplementation of specific trophic factors, and suggest that ATF3 expression may normally be induced by the loss of target-derived NGF and GDNF. [source] Intravascular lymphoma: a neoplasm of ,homeless' lymphocytes?HEMATOLOGICAL ONCOLOGY, Issue 3 2006Maurilio Ponzoni Abstract Intravascular lymphoma (IVL) is an extremely rare form of non-Hodgkin lymphoma characterized by almost exclusive growth of neoplastic lymphocytes within blood vessel lumen. IVL is morphologically characterized in most instances by large cells with B-cell lineage. IVL is an aggressive and usually disseminated disease that predominantly affects elderly patients, resulting in poor PS, B-symptoms, anemia, and high lactate dehydrogenase serum level. The brain and skin are the most commonly involved sites; nodal disease is rare. Survival after conventional chemotherapy is disappointing, with a relevant impact of diagnostic delay and lethal complications. Notwithstanding these results, IVL limited to the skin (cutaneous variant) is a favorable presentation with distinctive clinical characteristics. Moreover, differences in clinical presentation with Eastern Countries IVL cases, mostly associated with hemophagocytic syndrome, do exist. Intensive combinations containing drugs with higher central nervous system bioavailability are needed in cases with brain involvement; the role of high-dose chemotherapy with autologous stem cell transplantation should be investigated in younger patients with unfavorable features. The present review will discuss the most recent acquisitions related either to diagnosis and immunophenotypic/biologic characteristics as well as clinical/therapeutic issues of IVL. Copyright © 2006 John Wiley & Sons, Ltd. [source] Extracutaneous transformation into a high-grade lymphoma: a potential pitfall in the management of patients with Sézary syndromeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2006Sonja Michaelis MD Background, Transformation into a high-grade lymphoma in cutaneous T-cell lymphoma (CTCL) occurs in approximately 25% of cases and is associated with an aggressive clinical course. Methods, We identified four cases of transformation of Sézary syndrome (SS) into pleomorphic T-cell lymphoma. Results, In all patients, transformation occurred first in the lymph nodes, an average of 43 months after the diagnosis of SS. These high-grade lymphomas were composed of CD30-positive (two patients) and CD30-negative (two patients) pleomorphic large cells. All patients died of lymphoma an average of 29 months after nodal transformation. Conclusion, Because of an apparently poorer prognosis, the early recognition of transformation, especially by lymph node biopsy, is important for adequate therapy. [source] Lymphomatoid Papulosis Presenting With B-Cell Lymphoma: A New Association?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Galan Lymphomatoid papulosis (LyP) is a cutaneous T-cell lymphoproliferative disorder, characterised by recurrent crops of necrotic self-healing papules and nodules. Although chronic, LyP typically has a benign clinical course in the majority of cases. Histologically, a malignant appearing T-cell lymphoid infiltrate is seen. The atypical cells often resemble the cerebriform cells of mycosis fungoides or Reed-Sternberg cells in Hodgkin lymphoma. Approximately 10,20% of the patients go on to develop lymphomas, including mycosis fungoides, CD30-positive anaplastic large cell and Hodgkin lymphoma. We report a case of LyP associated with a B-cell lymphoma. A 50-year-old male, presented with scattered erythematous scaly papules, some with central crust, located on the arms, trunk and leg of one-month duration. A skin biopsy revealed a polymorphous infiltrate with many large atypical lymphocytes, resembling Reed Sternberg cells. By immunohistochemistry, the large cells were positive for T-cell markers and CD30. Subsequently, he developed fever, night sweats and diffuse lymphadenopathy. A lymph node biopsy showed a vaguely nodular proliferation of small to medium lymphocytes. Immunophenotypic and flow cytometric studies best characterised the process as mantle cell lymphoma. Although, LyP has been previously associated with lymphomas of above-mentioned types, this is an extremely unusual case presenting with a low-grade B-cell lymphoma. [source] Ultrastructural study of the precursor to fungiform papillae prior to the arrival of sensory nerves in the fetal ratJOURNAL OF MORPHOLOGY, Issue 3 2001Shin-ichi Iwasaki Abstract The structure of precursors to fungiform papillae without taste buds, prior to the arrival of sensory nerve fibers at the papillae, was examined in the fetal rat on embryonic day 13 (E13) and 16 (E16) by light and transmission electron microscopy in an attempt to clarify the mechanism of morphogenesis of these papillae. At E13, a row of rudiments of fungiform papillae was arranged along both sides of the median sulcus of the lingual dorsal surface, and each row consisted of about 10 rudiments. There was no apparent direct contact between papillae rudiments and sensory nerves at this time. Bilaterally towards the lateral side of the tongue, adjacent to these first rudiments of fungiform papillae, a series of cord-like invaginations of the dorsal epithelium of the tongue into the underlying connective tissue, representing additional papillary primordia parallel to the first row, was observed. The basal end of each invagination was enlarged as a round bulge, indented at its tip by a mound of fibroblasts protruding into the bulge. At E16 there was still no apparent direct contact between rudiments of fungiform papillae and sensory nerves. Each rudiment apically contained a spherical core of aggregating cells, which consisted of a dense assembly of large, oval cells unlike those in other areas of the lingual dorsal epithelium. The differentiation of these aggregated cells was unclear. The basal lamina was clearly recognizable between the epithelium of the rudiment of fungiform papillae and the underlying connective tissue. Spherical structures, which appeared to be sections of the cord-like invaginations of the lingual epithelium that appeared on E13, were observed within the connective tissue separated from the dorsal lingual epithelium. Transverse sections of such structures revealed four concentric layers of cells: a central core, an inner shell, an outer shell, and a layer of large cells. Bundles of fibers were arranged in the central core, and the diameters of bundles varied somewhat depending on the depth of the primordia within the connective tissue and their distance from the median sulcus. Ultrastructural features of cells in the outer shell differed significantly in rudiments close to the lingual epithelium as compared to those in deeper areas of connective tissue. Around the outer shell there was a large-cell layer consisting of one to three layers of radially elongated, oval cells that contained many variously sized, electron-dense, round granules. Large numbers of fibroblasts formed dense aggregates around each spherical rudiment, and were separated by the basal lamina from the large-cell epithelial layer. Progressing from deep-lying levels of the rudiments of the papillae to levels close to the lingual surface epithelium, the central core, inner shell, and outer shell gradually disappeared from the invaginated papillary cords. J. Morphol. 250:225,235, 2001. © 2001 Wiley-Liss, Inc. [source] The reaction of glial progenitor cells in remyelination following ethidium bromide-induced demyelination in the mouse spinal cordNEUROPATHOLOGY, Issue 4 2002Shigeko Fushimi The present study investigated how glial progenitor cells participated in the process of remyelination following ethidium bromide (EBr)-induced demyelination in the adult mouse spinal cord. In situ hybridization techniques for detecting mRNA for platelet-derived growth factor , receptor (PDGF,R) and proteolipid protein (PLP) were employed to identify glial progenitor cells and mature oligodendrocytes, respectively. During the demyelination stage and early stage of remyelination, large cells strongly expressing PDGF,R mRNA were observed in the border of the demyelinating lesion, and with immunohistochemistry they exhibited positive labeling of the astrocytic marker glial fibrillary acidic protein (GFAP). Other glial progenitor cells expressing PDGF,R mRNA proliferated around the lesion during the demyelination stage. During the remyelination stage, some PDGF,R mRNA-positive cells partly expressed mRNA for PLP in the periphery of the demyelinating lesion. These results suggest that PDGF,R mRNA-positive glial progenitor cells may give rise to both astrocytes and oligodendrocytes, which participate in remyelination following demyelination. [source] Nodular lymphocyte predominant Hodgkin lymphoma at atypical locations may be associated with increased numbers of large cells and a diffuse histologic componentAMERICAN JOURNAL OF HEMATOLOGY, Issue 3 2008David T. Yang Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) typically affects predictable lymph node groups with excellent treatment outcomes, but cases with a diffuse histologic pattern are associated with recurrence and rarely, cases will transform to diffuse large B-cell lymphoma. Although increased numbers of large cells has not been associated with poor prognosis, transformation is thought to histologically progress through a stage distinguished by increasing numbers of large atypical B-cells. From 55 cases of NLPHL, we describe a possible subset of NLPHL occurring in older individuals at atypical sites, associated with increased numbers of large cells, a diffuse histologic component, and expression of Bcl-2. Am. J. Hematol., 2008. © 2007 Wiley-Liss, Inc. [source] Impact of Solar Ultraviolet Radiation on Marine Phytoplankton of Patagonia, Argentina,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005E. Walter Helbling ABSTRACT Patagonia area is located in close proximity to the Antarctic ozone "hole" and thus receives enhanced ultraviolet B (UV-B) radiation (280,315 nm) in addition to the normal levels of ultraviolet A (UV-A; 315,400 nm) and photosynthetically available radiation (PAR; 400-700 nm). In marine ecosystems of Patagonia, normal ultraviolet radiation (UVR) levels affect phytoplankton assemblages during the three phases of the annual succession: (1) prebloom season (late summer-fall), (2) bloom season (winter-early spring) and (3) postbloom season (late spring-summer). Small-size cells characterize the pre-and postbloom communities, which have a relatively high photosynthetic inhibition because of high UVR levels during those seasons. During the bloom, characterized by micro-plankton diatoms, photosynthetic inhibition is low because of the low UVR levels reaching the earth's surface during winter; this community, however, is more sensitive to UV-B when inhibition is normalized by irradiance (i.e. biological weighting functions). In situ studies have shown that UVR significantly affects not only photosynthesis but also the DNA molecule, but these negative effects are rapidly reduced in the water column because of the differential attenuation of solar radiation. UVR also affects photosynthesis versus irradiance (P vs E) parameters of some natural phytoplankton assemblages (i.e. during the pre- but not during the postbloom season). However, there is a significant temporal variability of P vs E parameters, which are influenced by the nutrient status of cells and taxonomic composition; taxonomic composition is in turn associated with the stratification conditions (e.g. wind speed and duration). In Patagonia, wind speed is one of the most important variables that conditions the development of the winter bloom by regulating the depth of the upper mixed layer (UML) and hence the mean irradiance received by cells. Studies on the interactive effects of UVR and mixing show that responses of phytoplankton vary according to the taxonomic composition and cell structure of assemblages; therefore cells use UVR if >90% of the euphotic zone is being mixed. In fact, cell size plays a very important role when estimating the impact of UVR on phytoplankton, with large cells being more sensitive when determining photosynthesis inhibition, whereas small cells are more sensitive to DNA damage. Finally, in long-term experiments, it was determined that UVR can shape the diatom community structure in some assemblages of coastal waters, but it is virtually unknown how these changes affect the trophody-namics of marine systems. Future studies should consider the combined effects of UVR on both phytoplankton and grazers to establish potential changes in biodiversity of the area. [source] The inner ear of the lungfish ProtopterusTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 3 2004Christopher Platt Abstract The sensory end organs of the inner ear of the lungfish, Protopterus, were examined using scanning and transmission electron microscopy. The utricle has a structure and hair cell orientation pattern that are typical for vertebrates, although the hair cells are unusually large. There are the typical three semicircular canals extending from the utricle, with the typical hair cell orientations, but the lateral canal sensory crista looks like the "hemicrista" of some amphibians and amniotes, lacking a saddle-shaped flare on one wall of the ampulla. Unlike most vertebrates that have the saccule and lagena as two separate pouches ventral to the utricle, the lungfish has a single large ventral pouch that contains a single large pasty otoconial mass. This mass covers two hair cell patches, each like a striola with prominent hair cell ciliary bundles, that are presumed to represent saccular and lagenar maculae. However, these two major sensory patches are not completely separate maculae because they lie within a less densely populated field of smaller hair cells, which forms an extrastriolar region that surrounds and fills the region between the two striolae of higher hair cell density. The more caudal lagenar striola is a vertically elongated stripe with hair cell orientation vectors facing antiparallel on either side of a midline drawn vertically along the macula, resembling the macula lagena of some bony fishes but not of tetrapods. The more rostral saccular striola is a curving band with hair cell orientation vectors facing away from its midline, but because this macula curves in three dimensions, the vectors at the rostral end of this striola are oriented mediolaterally, whereas the vectors on the caudal half of this striola are oriented dorsoventrally. The presence of a macula neglecta was confirmed near the posterior canal as a tiny single patch of a few dozen hair cells with all the cell orientations directed caudally. The ciliary bundles on the cells in the striolar-like regions of all of three otolithic organs average over 80 cilia, a number far greater than for any other fish studied to date. The features of the single sacculolagenar pouch with separate striolar-like regions, the cellular orientation in the otolith organs, and the large cells and ciliary bundles in Protopterus also were observed in specimens of the other extant lungfish genera, Lepidosiren and Neoceratodus. J. Comp. Neurol. 471:277,288, 2004. © 2004 Wiley-Liss, Inc. [source] Frequent occurrence of B-cell lymphomas in angioimmunoblastic T-cell lymphoma and proliferation of Epstein,Barr virus-infected cells in early casesBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2007Klaus Willenbrock Summary Secondary lymphomas occurring in the setting of angioimmunoblastic T-cell lymphoma (AILT) are considered to be rare. Their occurrence has been attributed to Epstein,Barr virus (EBV)-associated lymphoproliferations. A previous study detected a dysregulated hypermutation process in B-cells of AILT. The present study aimed at estimating the frequency of B-cell lymphomas in AILT. By studying the expression of EBV and activation-induced cytidine deaminase (AID) as an indicator of hypermutating cells, we assessed whether B-cell lymphoproliferations in AILT were strictly associated with EBV and whether hypermutation might contribute to lymphomagenesis. Among 161 cases of AILT, diagnosed between 1996 and 2005 at the lymph node registry, Frankfurt, Germany, 19 cases were detected that also had B-cell non-Hodgkin lymphoma (NHL) and two cases had classical Hodgkin lymphoma (HL). EBV was detected in tumour cells of 7/18 NHL and both HL, suggesting that factors other than EBV contribute to lymphomagenesis. AID was expressed in AILT in large cells disseminated in the tissue, implying that the process of somatic hypermutation is ongoing in AILT, although the GC architecture is disrupted. This might be relevant in the development of secondary lymphomas. [source] Transforming Growth Factor-, Induces the Differentiation of Sarcomatoid Cholangiocarcinoma CellsCANCER SCIENCE, Issue 2 2000Munechika Enjoji A sarcomatoid cholangiocarcinoma cell line, ETK-1, was established from a patient. Phenotypically, the cells corresponded to immature biliary epithelial cells. Because a small number of ETK-1 cells appeared to differentiate spontaneously along a biliary epithelial lineage in continuous culture, we examined the factors that initiate and/or promote the differentiation of the cells. Transforming growth factor-, (TGF,) induced significant changes in ETK-1 cells. After stimulation with the factor, ETK-1 cells displayed morphologic transformation at a much higher frequency, with the appearance of many large cells with intracytoplasmic vacuoles, and the production of mucinous substances. These morphologically transformed cells were phenotypically similar to welldifferentiated adenocarcinoma cells. The expression pattern of integrins after TGF, treatment also supported the maturation of the ETK-1 cells. The antibody against the receptor of TGF, inhibited these changes by TGF,. Moreover, the proliferation rate of ETK-1 cells was suppressed by TGF,. Our data suggest that TGF, can act as a differentiation factor along a biliary epithelial lineage. [source] Case Series: Intraocular lymphoma diagnosed by fine-needle aspiration biopsyACTA OPHTHALMOLOGICA, Issue 6 2010Shaden Sarafzadeh Acta Ophthalmol. 2010: 88: 705,710 Abstract. Purpose:, To describe clinical experience in the diagnosis of intraocular lymphoma by fine-needle aspiration biopsy (FNAB) in patients with one or more discrete intraocular infiltrative lesions and limited or absent intravitreal tumour cells. Methods:, Retrospective descriptive analysis of patients who underwent intraocular FNAB of a solid retinal, subretinal pigment epithelial or uveal tumour that proved to be a malignant lymphoma. Results:, After exclusions, our study group consisted of seven patients, each of whom had one or more discrete intraocular infiltrative lesions and limited or absent intravitreal tumour cells and underwent a diagnostic intraocular FNAB that confirmed malignant intraocular lymphoma cytopathologically. These included three patients with one or more geographic yellow subretinal pigment epithelial infiltrates and one patient each with a prominent nodular white subretinal pigment epithelial tumour, a rapidly developing solid placoid choroidal mass, a haemorrhagic retinal infiltrative lesion and an infiltrative iris tumour, respectively. A prominent feature of virtually all aspirates was a large proportion of degenerated lymphoid cells in the background. Cytologically intact tumour cells ranged from relatively homogeneous small round cells with large nucleus to cytoplasm ratio to pleomorphic large cells with irregular knob-like nuclear protrusions. Immunocytochemical stains for lymphoid markers were helpful in confirming the pathological diagnosis of lymphoma in the five patients in whom this testing was performed. Conclusion:, FNAB was a useful diagnostic tool in the described subgroup of patients with suspected intraocular lymphoma. FNAB should be considered as a diagnostic option in selected patients with suspected intraocular lymphoma, especially if there are few or no vitreous cells. [source] | |||||||||||||||||||||||||