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Cell Components (cell + component)
Kinds of Cell Components Selected AbstractsReview: Durability and Degradation Issues of PEM Fuel Cell ComponentsFUEL CELLS, Issue 1 2008F. A. de Bruijn Abstract Besides cost reduction, durability is the most important issue to be solved before commercialisation of PEM Fuel Cells can be successful. For a fuel cell operating under constant load conditions, at a relative humidity close to 100% and at a temperature of maximum 75,°C, using optimal stack and flow design, the voltage degradation can be as low as 1,2,,V·h. However, the degradation rates can increase by orders of magnitude when conditions include some of the following, i.e. load cycling, start,stop cycles, low humidification or humidification cycling, temperatures of 90,°C or higher and fuel starvation. This review paper aims at assessing the degradation mechanisms of membranes, electrodes, bipolar plates and seals. By collecting long-term experiments as well, the relative importance of these degradation mechanisms and the operating conditions become apparent. [source] Thermochemical Compatibility of a Seal Glass with Different Solid Oxide Cell ComponentsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 1 2010Manoj K. Mahapatra Thermochemical compatibility of an aluminosilicate glass (SABS-0) with Crofer 22 APU, nickel, and NiTiHf alloy has been studied for solid oxide cell use. Local SABS-0 devitrification occurs near the interfaces of Crofer 22 APU/SABS-0 and Ni/SABS-0 samples. But extensive SABS-0 devitrification is observed at the NiTiHf/SABS-0 interface. The SABS-0 elements diffuse a few microns into the Crofer 22 APU alloy and the nickel, or vice versa. But the SABS-0 and NiTiHf elements diffuse into each other at ,25 ,m. The SABS-0 glass is thermochemically compatible with the Crofer 22 APU and the nickel but not with the NiTiHf alloy. [source] Holocrine secretion and cytoplasmic content of Helleborus foetidus L. (Ranunculaceae) nectarPLANT BIOLOGY, Issue 2 2008J. L. Vesprini Abstract We used electron microscopy to investigate the fine structure of nectary secretions of Helleborus foetidus. During the secretion period, epidermal cells of nectaries discharge the whole contents of the cytoplasm into the nectary cavity. The external wall of the cell breaks, releasing the cytoplasm as a dense aggregate that later disperses in the nectary cavity. Cell components, such as chromatin, plastids, mitochondria, lipid droplets and membranes, were found in the nectar of H. foetidus, evincing the complex nature of the secreted material. These results confirm that nectar secretion in H. foetidus is of the holocrine type. [source] NG2 proteoglycan is expressed exclusively by mural cells during vascular morphogenesisDEVELOPMENTAL DYNAMICS, Issue 2 2001Ugur Ozerdem Abstract Immunofluorescence mapping demonstrates that the NG2 proteoglycan is invariably expressed by the mural cell component of mouse neovascular structures. This pattern is independent of the developmental mechanism responsible for formation of the vasculature (vasculogenesis or angiogenesis). Thus, NG2 is expressed in the embryonic heart by cardiomyocytes, in developing macrovasculature by smooth muscle cells, and in nascent microvessels by vascular pericytes. Due to the scarcity of proven markers for developing pericytes, NG2 is especially useful for identification of this cell type. The utility of NG2 as a pericyte marker is illustrated by two observations. First, pericytes are associated with endothelial tubes at an early point in microvessel development. This early interaction between pericytes and endothelial cells has important implications for the role of pericytes in the development and stabilization of microvascular tubes. Second, the pericyte to endothelial cell ratio in developing capillaries varies from tissue to tissue. Because the extent of pericyte investment is likely to affect the physical properties of the vessel in question, it is important to understand the mechanisms that control this process. Additional insight into these and other aspects of vascular morphogenesis should be possible through use of NG2 as a mural cell marker. © 2001 Wiley-Liss, Inc. [source] Fusion of ALK to the Ran-binding protein 2 (RANBP2) gene in inflammatory myofibroblastic tumorGENES, CHROMOSOMES AND CANCER, Issue 1 2003Zhigui Ma Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal proliferation of transformed myofibroblasts, with a prominent inflammatory cell component, that can mimic other spindle cell processes such as nodular fasciitis, desmoid tumor, and gastrointestinal stromal tumor. Genetic analyses have recently demonstrated rearrangements of anaplastic lymphoma kinase (ALK), located at 2p23, in a subset of IMTs. Molecular characterizations have identified ALK fusions involving tropomyosin-3 and -4 (TPM-3 and -4), the clathrin heavy chain (CLTC), and the cysteinyl-tRNA synthetase (CARS) genes as fusion partners. Here we describe two IMTs with a novel ALK fusion that involves the Ran-binding protein 2 (RANBP2) gene at 2q13, which normally encodes a large (358-kDa) nucleopore protein localized at the cytoplasmic side of the nuclear pore complex. The N-terminal 867 residues of RANBP2 are fused to the cytoplasmic segment of ALK in the 1,430,amino acid RANBP2-ALK chimeric protein. Myofibroblasts that express RANBP2-ALK exhibit nuclear membrane-associated ALK staining that is unique compared to the subcellular localization observed with other ALK fusions in IMT, presumably attributable to heteroassociation of the fusion with normal RANBP2 at the nuclear pore. These findings expand the spectrum of ALK abnormalities observed in IMT and further confirm the clonal, neoplastic nature of these lesions. © 2003 Wiley-Liss, Inc. [source] Molecular-cytogenetic comparison of mucosa-associated marginal zone B-cell lymphoma and large B-cell lymphoma arising in the gastro-intestinal tractGENES, CHROMOSOMES AND CANCER, Issue 4 2001Thomas F.E. Barth Extranodal B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type may represent a model of lymphoma progression, because a small cell component frequently occurs in the large cell variants. We studied 52 extranodal B-cell lymphomas: 18 extranodal marginal zone B-cell lymphomas of MALT type (MZBL,MT), 7 MZBL,MT of the gastro-intestinal tract with a diffuse large B-cell component (giMZBLplusLBCL), and 27 diffuse large B-cell lymphomas of the gastro-intestinal tract without small cell component (giLBCL). Analytical techniques were comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). The translocation t(11;18) was found as the sole aberration in two MZBL,MT only. In contrast to this, t(11;18)-negative MZBL,MT were characterized by frequent gains on chromosome 3 and DNA amplifications on 2p13,p15. Furthermore, we found a clonal lymphoma progression from the small to the large cell component with accumulation of gains and losses of chromosomal material in the large cell component in giMZBLplusLBCL. Aberrations overlapping with MZBL,MT and giMZBLplusLBCL included losses on chromosome 13, amplifications of the REL proto-oncogene, or gains on chromosome 12. In addition, the large cell component revealed gains on 8q24, including amplifications of the MYC proto-oncogene, and losses on 2q. The giLBCL had frequent gains on chromosomes 12 and 9, as well as on 11q, and losses on 6q. We conclude that, based on the distinctive and partly overlapping patterns of genetic aberrations, MALT lymphomas can be divided into different genetic subgroups. © 2001 Wiley-Liss, Inc. [source] Primary cutaneous myxoid spindle cell squamous cell carcinoma: a clinicopathologic study and review of the literatureJOURNAL OF CUTANEOUS PATHOLOGY, Issue 4 2010Aparche Yang Mucocutaneous squamous cell carcinoma (SCC) may rarely exhibit intracellular mucin production. Extracellular mucin production is an even rarer finding in SCC that is not well documented in the literature. Here, we report six cases of primary cutaneous and mucocutaneous SCC with prominent extracellular stromal mucin deposition and an epithelial spindle cell component. We propose the term ,yxoid spindle cell SCC' (MSC SCC) to describe the histologic characteristics of these six cases. We also propose a set of histologic and immunohistochemical findings for distinguishing MSC SCC from primary cutaneous and metastatic spindle cell neoplasms including other sarcomatoid carcinomas, myxoid sarcomas and the spindle cell variant of atypical fibroxanthoma (AFX). The criteria can also help discern MSC SCC from spindle cell melanomas, which may rarely show a prominent myxoid stroma. Given the small numbers of cases reported to date, the presence of prominent myxoid stroma in primary cutaneous spindle cell SCC has unknown prognostic significance at this time. Yang A, Hanley A, Velazquez EF, Cassarino DS. Primary cutaneous myxoid spindle cell squamous cell carcinoma: a clinicopathologic study and review of the literature. [source] Expression of extracellular matrix genes in cultured hepatic oval cells: an origin of hepatic stellate cells through transforming growth factor beta?LIVER INTERNATIONAL, Issue 4 2009Ping Wang Abstract Background: Hepatic oval cells, progenitor cells in the liver, can differentiate into hepatocytes and bile duct cells both in vitro and in vivo. Although hepatic stellate cells are another important cell component in the liver, less attention has been focused on the relationship between hepatic oval cells and hepatic stellate cells. Methods: Hepatic oval cells were isolated from rats fed a choline-deficient diet supplemented with 0.1% ethionine for 6 weeks and characterized by electron microscopy, flow cytometry, reverse transcription polymerase chain reaction, Western blot and bi-direction differentiation. After treatment with transforming growth factor-,1 (TGF-,1), changes in cell viability, morphology, extracellular matrix (ECM) expression and immune phenotype were analysed in these cultured and adherent hepatic oval cells. Results: The primary cultured hepatic oval cells were positive for the oval cell-specific markers OV-6, BD-1/BD-2 and M2PK as well as the hepatocyte markers albumin and ,-foetoprotein. These hepatic oval cells differentiated bipotentially into hepatocytes or bile duct-like cells under appropriate conditions. It is noteworthy that these bipotential hepatic oval cells expressed ECM genes stably, including collagens, matrix metalloproteinases and tissue inhibitor of mellatoproteinase. Furthermore, except for growth inhibition and morphological changes in the hepatic oval cells after exposure to TGF-,1, there was an increased expression of ECM genes, the onset expression of snail and loss expression of E-cadherin. During this process, TGF-,1 treatment induced an upregulation of marker genes for hepatic stellate cells in hepatic oval cells, such as desmin and GFAP. Conclusion: Except for the expression of ECM, the cultured hepatic oval cells could induce an increased expression of hepatic stellate cell markers by TGF-,1 through an epithelial,mesenchymal transition process, which might indicate the contribution of hepatic oval cells to liver fibrosis. [source] Von Hippel-Lindau diseaseMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2003Toshiaki Sano Abstract Von Hippel-Lindau (VHL) disease is an uncommon, autosomal dominant hereditary multitumor syndrome caused by germline alterations of the VHL gene, which has been cloned recently and identified as a tumor suppressor gene. The major lesions in VHL disease include hemangioblastomas in the central nervous system and retina, clear cell renal cell carcinomas, pheochromocytomas, pancreatic tumors, epididymal cystadenomas, endolymphatic sac tumors, carcinoid tumors, and multiple cysts of the kidney, pancreas, and epididymis. Compared with sporadic ones, the tumors in VHL disease develop at an earlier age and often multifocally. Histologic features of VHL tumors are characterized by their high degree of vascularization and the presence of a clear cell component. Hypervascularization is induced by overexpression of vascular endothelial growth factor (VEGF), and because the principal function of VHL protein is the negative regulation of hypoxia-inducible mRNAs including VEGF mRNA, inactivation of VHL gene plays critical roles in angiogenesis of the VHL tumors. In addition, since VHL protein is also required for the down-regulation of transcription activity of certain genes for the cell growth and cell cycle, inactivation of VHL gene may contribute to tumorigenesis of the VHL tumors. A significant difference in the frequency of types of VHL gene mutation has been noted among the affected families, known as the genotype-phenotype correlations. Microsc. Res. Tech. 60:159,164, 2003. © 2003 Wiley-Liss, Inc. [source] Histologically low-grade dedifferentiated liposarcoma of the retroperitoneumPATHOLOGY INTERNATIONAL, Issue 5 2001Masaharu Fukunaga A low-grade dedifferentiated liposarcoma in the retroperitoneum of a 52-year-old woman is described. The excised specimens contained six nodules of lipoma-like well-differentiated liposarcoma and a nodule of dedifferentiated liposarcoma. The latter was composed predominantly of loosely arranged, benign-appearing spindle cells and fat cells. A small number of cells with irregularly shaped nuclei were scattered. There were no mitotic figures. The fat cells showed slight variation of size and shape, and a few multivacuolated lipoblasts were found. The spindle cell areas occupied approximately 60% of the tumor. The stroma was somewhat fibrous and myxoid and no dense collagenous matrix was found. The stroma vascularity was not prominent. Immunohistochemically, the spindle cells were positive for vimentin but negative for S-100 protein, desmin, muscle actin, and , -smooth muscle actin. Follow up for 5 months showed no evidence of recurrence or metastasis. The tumor, in which the benign-appearing spindle cell component was predominant, was considered to be a low-grade dedifferentiated liposarcoma. Close and long-term follow up is required. In retroperitoneal lipoma-like well-differentiated liposarcomas, spindle cell components like the present tumor, which represent dedifferentiation, should not be overlooked. [source] OCT4: biological functions and clinical applications as a marker of germ cell neoplasiaTHE JOURNAL OF PATHOLOGY, Issue 1 2007L Cheng Abstract Germ cell tumours (GCTs) are a heterogeneous group of neoplasms, which develop in the gonads as well as in extragonadal sites, that share morphological patterns and an overall good prognosis, owing to their responsiveness to current surgical, chemotherapeutic, and radiotherapeutic measures. GCTs demonstrate extremely interesting biological features because of their close relationships with normal embryonal development as demonstrated by the pluripotentiality of some undifferentiated GCT variants. The similarities between GCTs and normal germ cell development have made it possible to identify possible pathogenetic pathways in neoplastic transformation and progression of GCTs. Genotypic and immunophenotypic profiles of these tumours are also useful in establishing and narrowing the differential diagnosis in cases of suspected GCTs. Recently, OCT4 (also known as OCT3 or POU5F1), a transcription factor that has been recognized as fundamental in the maintenance of pluripotency in embryonic stem cells and primordial germ cells, has been proposed as a useful marker for GCTs that exhibit features of pluripotentiality, specifically seminoma/dysgerminoma/germinoma and embryonal carcinoma. The development of commercially available OCT4-specific antibodies suitable for immunohistochemistry on paraffin-embedded specimens has generated increasing numbers of reports of OCT4 expression in a wide variety of gonadal and extragonadal GCTs. OCT4 immunostaining has been shown to be a sensitive and specific marker for seminomatous/(dys)germinomatous tumours and in embryonal carcinoma variants of non-seminomatous GCTs, whether in primary gonadal or extragonadal sites or in metastatic lesions. Therefore, OCT4 immunohistochemistry is an additional helpful marker both in the differential diagnosis of specific histological subtypes of GCTs and in establishing a germ cell origin for some metastatic tumours of uncertain primary. OCT4 expression has also been reported in pre-invasive conditions such as intratubular germ cell neoplasia, unclassified (IGCNU) and the germ cell component of gonadoblastoma. Additionally, OCT4 immunostaining shows promise as a useful tool in managing patients known to be at high risk for the development of invasive GCTs. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] The Excurrent Ducts of the Testis of the Emu (Dromaius novaehollandiae) and Ostrich (Struthio camelus): Microstereology of the Epididymis and Immunohistochemistry of its Cytoskeletal SystemsANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010P. C. Ozegbe Summary The volumetric proportion of the various ducts of the epididymis of the emu and ostrich and the immunohistochemistry of actin microfilaments, as well as cytokeratin, desmin and vimentin intermediate filaments, were studied in the various ducts of the epididymis of the emu and ostrich. The volumetric proportions of various ducts, which are remarkably different from those of members of the Galloanserae monophyly, are as follows: the rete testis, 5.2 ± 1.4% for the emu and 2.4 ± 1.8% for the ostrich; efferent ducts, 14.2 ± 2.3% (emu) and 11.8 ± 1.8% (ostrich); epididymal duct unit, 25.8 ± 5.8% (emu) and 26.1 ± 4.1% (ostrich) and connective tissue and its content, 54.7 ± 5.8% (emu) and 60.0 ± 4.9% (ostrich). Unlike in mammals and members of the Galloanserae monophyly, only vimentin was immunohistochemically demonstrated in the rete testis epithelium of the emu, and none of the cytoskeletal protein elements in the ostrich rete testis. The epithelium of the efferent ducts of the emu co-expressed actin, cytokeratin and desmin in the non-ciliated type I cells, and vimentin in the ciliated cell component. The ostrich demonstrated only cytokeratin in this epithelium. The ratite epididymal duct unit is different from that of mammals in lacking actin (only weaky expression in the ostrich), desmin and cytokeratin, and a moderate/strong immunoexpression of vimentin in the basal cells and basal parts of the NC type III cell in the epididymal duct unit. Immunoexpression of the microfilaments and intermediate filaments varied between the two ratite birds, as has been demonstrated previously in birds of the Galloanserae monophyly, and in mammals. [source] Delineating the impact of neuroantigen vs genetic diversity on MP4-induced EAE of C57BL/6 and B6.129 miceAPMIS, Issue 12 2009STEFANIE KUERTEN MBP-PLP fusion protein (MP4)-induced experimental autoimmune encephalomyelitis (EAE) is a model for multiple sclerosis (MS) that encompasses both a time-dependent attack on central nervous system (CNS) regions and a B cell component, mirroring important features of human multiple sclerosis. Comparing C57BL/6 with B6.129 mice immunized with MP4, we point out similarities regarding these hallmarks and thus propose that they are largely dependent on the nature of the MP4 antigen itself, while differences between the two strains suggest that additional fine-tuning is brought about by the genetic repertoire of the animal. Overall, our data imply that (i) the interplay between both the antigenic trigger and genetic variables can define the outcome of MP4-induced autoimmune encephalomyelitis in C57BL/6 and B6.129 mice and (ii) that MP4 is not only a strong neuroantigen when it comes to reproducing the dynamics in effector mechanisms as is typical of the disease but also a promising agent for studying interindividual heterogeneity derived from genetic diversity in EAE/MS. [source] Squamous cell carcinoma with sarcomatous stroma in the nasal cavity of a dogAUSTRALIAN VETERINARY JOURNAL, Issue 9 2004KL BOSWARD This is a report of an unusual squamous cell carcinoma in the nasal cavity of a dog. A 13-year-old Golden Retriever was presented with a unilateral nasal and ocular discharge. Although a nasal tumour was suspected, initial diagnostic investigations were unrewarding, and, with worsening clinical signs, the dog was euthanased. Necropsy examination confirmed the presence of a nasal tumour that was composed histologically of both a well-differentiated squamous cell carcinoma component blending with a predominant spindle cell component. Immunohistochemical staining with anti-human keratin/cytokeratin (AE1/AE3, CAM 5.2 and broad spectrum cytokeratin), Vimentin, Desmin, smooth muscle actin and S-100 protein supported a diagnosis of a squamous cell carcinoma with (pseudo) sarcomatous stroma. [source] Angiocentric Neuroepithelial Tumor (ANET): A New Epilepsy-Related Clinicopathological Entity with Distinctive MRIBRAIN PATHOLOGY, Issue 4 2005Arielle Lellouch-Tubiana MD Several types of glioneuronal tumors are known to induce intractable partial seizures in children and adults. The most frequent are dysembryoplastic neuroepithelial tumors (DNETs) and gangliogliomas. We report here a new clinicopathological entity within the spectrum of glioneuronal tumors observed in 10 children who underwent surgery for refractory epilepsy. These tumors demonstrate a unique, pathognomonic histological pattern and a specific appearance at magnetic resonance imaging (MRI). The most striking neuropathological feature is an angiocentric polarity of the tumor with gliofibrillary acidic protein (GFAP) positive fusiform and bipolar astrocytic cells arranged around blood vessels (perivascular cuffing with tumoral astrocytes). Characteristic MRI findings include involvement of cortical gray and white matter, intrinsically high signal on T1-weighted images, as well as a stalk like extension to the ventricle. Immunohistochemical neuronal markers (neurofilament protein, synaptophysin and chromogranin) confirm the presence of a neuronal cell component. Therefore, the term angiocentric neuroepithelial tumor (ANET) is proposed. [source] Compatible solutes of organisms that live in hot saline environmentsENVIRONMENTAL MICROBIOLOGY, Issue 9 2002Helena Santos Summary The accumulation of organic solutes is a prerequisite for osmotic adjustment of all microorganisms. Thermophilic and hyperthermophilic organisms generally accumulate very unusual compatible solutes namely, di- myo -inositol-phosphate, di-mannosyl-di- myo -inositol-phosphate, di-glycerol-phosphate, mannosylglycerate and mannosylglyceramide, which have not been identified in bacteria or archaea that grow at low and moderate temperatures. There is also a growing awareness that some of these compatible solutes may have a role in the protection of cell components against thermal denaturation. Mannosylglycerate and di-glycerol-phosphate have been shown to protect enzymes and proteins from thermal denaturation in vitro as well, or better, than compatible solutes from mesophiles. The pathways leading to the synthesis of some of these compatible solutes from thermophiles and hyperthermophiles have been elucidated. However, large numbers of questions remain unanswered. Fundamental and applied interest in compatible solutes and osmotic adjustment in these organisms, drives research that, will, in the near future, allow us to understand the role of compatible solutes in osmotic protection and thermoprotection of some of the most fascinating organisms known on Earth. [source] Metabolism of fluoranthene in different plant cell cultures and intact plantsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2000Marit Kolb Abstract The metabolism of fluoranthene was investigated in 11 cell cultures of different plant species using a [14C]-labeled standard. Most species metabolized less than 5% of fluoranthene to soluble metabolites and formed less than 5% nonextractable residues during the standardized 48-h test procedure. Higher metabolic rates were observed in lettuce (Lactuca sativa, 6%), wheat (Tricitum aestivum, 9%), and tomato (Lycopersicon esculentum, 15%). A special high metabolic rate of nearly 50% was determined for the rose species Paul's Scarlet. Chromatographic analysis of metabolites extracted from aseptically grown tomato plants proved that the metabolites detected in the cell cultures were also formed in the intact plants. Metabolites produced in tomato and rose cells from [14C]-fluoranthene were conjugated with glucose, glucuronic acid, and other cell components. After acid hydrolyses, the main metabolite of both species was 1-hydroxyfluoranthene as identified by gas chromatography,mass spectrometry and high-performance liquid chromatography with diode array detection. The second metabolite formed by both species was 8-hydroxy-fluoranthene. A third metabolite in tomatoes was 3-hydroxyfluoranthene. [source] Redox Cycling of Ni-Based Solid Oxide Fuel Cell Anodes: A ReviewFUEL CELLS, Issue 3 2007D. Sarantaridis Abstract The published literature relating to damage to SOFCs caused by redox cycling of Ni-based anodes is reviewed. The review covers the kinetics of Ni oxidation and NiO reduction (as single phases and as constituents of composites with yttria-stabilised zirconia, YSZ), the dimensional changes associated with redox cycling and the effect of this on the mechanical integrity and electrical performance of cells and stacks. A critical parameter is the expansion strain that is caused by oxidation. Several studies report that the first complete oxidation of a Ni/YSZ composite causes a linear expansion of the order of 1%, but the actual values vary substantially between different investigations. The oxidation strain is the result of microstructural irreversibility during the redox process and leads to strain accumulation over several redox cycles. This can cause mechanical disruption to an anode, anode support or other cell components attached to the anode. A simplified mechanical model of the stress and damage that are likely to be caused by anode expansion is proposed and applied to anode-supported, electrolyte-supported and inert substrate-supported cell configurations. This allows the maximum oxidation strain to avoid damage in each configuration to be estimated. [source] EGFR and KRAS status of primary sarcomatoid carcinomas of the lung: Implications for anti-EGFR treatment of a rare lung malignancyINTERNATIONAL JOURNAL OF CANCER, Issue 10 2009Antoine Italiano Abstract Sarcomatoid carcinomas (SC) of the lung are uncommon malignant tumors composed of carcinomatous and sarcomatous cell components and characterized by a more aggressive outcome than other histological subtypes of nonsmall cell lung cancer (NSCLC). Although epidermal growth factor receptor (EGFR)-targeted therapies have emerged as a promising therapeutic approach in patients with advanced typical NSCLC such as adenocarcinoma, the potential clinical activity of these drugs in lung SC is still unknown. To investigate this point, we have analyzed the status of 4 EGFR pathways biomarkers in a series of lung SC. EGFR protein expression, EGFR gene copy number, EGFR mutational status and KRAS mutational status were assessed in a series of 22 consecutive cases of primary lung SC. EGFR protein overexpression was observed in all the cases. High level of polysomy (,4 copies of the gene in >40% of cells) was detected in 5 cases (23%). No EGFR mutation was detected. KRAS mutations were found in 8 patients (38%; Gly12Cys in 6 cases and Gly12Val in 2 cases). The consistent EGFR protein overexpression and the high rate of KRAS mutation may contribute to the poorer outcome of lung SC in comparison with typical NSCLC. The rare incidence of increased EGFR gene copy number, the lack of EGFR mutation and the high rate of KRAS mutation observed in our series also suggest that most patients with lung SC are not likely to benefit from anti-EGFR therapies. © 2009 UICC [source] Low-grade renal epithelial tumor originating from the distal nephronINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2004NOBORU HARA Abstract, There are few published reports of low-grade renal epithelial tumor originating from the distal nephron. However, it should not be disregarded clinically, because the actual number of patients with such tumors may be higher than expected. We investigated the immunohistochemical profile of a histologically distinct subtype of such a tumor in detail, in addition to the clinical course and imaging studies. The present study demonstrated that both glandular and spindle cell components of this tumor have a persistent characteristic of an epithelial tumor arising from the distal tubule or collecting duct. This tumor is a benign complex neoplasm that can be treated successfully with radical surgery. Beta-catenin and E-cadherin are suggested to play a crucial role in tumorigenesis and the biphasic arrangement of this neoplasm, concerning the expression of epithelial membrane antigen and carbohydrate antigen 19-9. We suggest that the term ,distal nephron epithelioma' is appropriate for classifying such rare but clinicopathologically distinct tumors. [source] Relationship between inactivation kinetics of a Listeria monocytogenes suspension by chlorine and its chlorine demandJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2004R. Virto Abstract Aims:, Chlorine demand by Listeria monocytogenes cells and inactivation of L. monocytogenes by chlorine (0·6,1·0 mg l,1) at different temperatures (4, 20 and 30°C) have been investigated in a batch reactor. Methods and Results:, Chlorine demand depended on the microbial concentration and was independent on the initial chlorine concentration and temperature. Chlorine decay was modelled by the addition of two first-order decay equations. Inactivation of L. monocytogenes by chlorine depended on the initial microbial concentration, initial chlorine concentration and temperature. A mathematical model based on a biphasic inactivation properly described survival curves of L. monocytogenes and a tertiary model was developed that satisfactorily predicted the inactivation of L. monocytogenes by different concentrations of initial chlorine at different temperatures. Conclusions:, Both available chlorine decay and inactivation of L. monocytogenes by chlorine were biphasic and can be modelled by a two-term exponential model. Significance and Impact of the Study:, The biphasic nature of survival curves of L. monocytogenes did not reflect the effect of a change of available chlorine concentration during the treatment. The microbial inactivation was caused by successive reactions that occur after the consumption of the chlorine by the bacterial cell components. [source] Signal transduction and functional changes in neutrophils with agingAGING CELL, Issue 4 2004Tamas Fulop Summary It is well known that the immune response decreases during aging, leading to a higher susceptibility to infections, cancers and autoimmune disorders. Most widely studied have been alterations in the adaptive immune response. Recently, the role of the innate immune response as a first-line defence against bacterial invasion and as a modulator of the adaptive immune response has become more widely recognized. One of the most important cell components of the innate response is neutrophils and it is therefore important to elucidate their function during aging. With aging there is an alteration of the receptor-driven functions of human neutrophils, such as superoxide anion production, chemotaxis and apoptosis. One of the alterations underlying these functional changes is a decrease in signalling elicited by specific receptors. Alterations were also found in the neutrophil membrane lipid rafts. These alterations in neutrophil functions and signal transduction that occur during aging might contribute to the significant increase in infections in old age. [source] Recovery of,Salmonella enterica,Serovars Typhimurium and Tennessee in Peanut Butter after Electron Beam ExposureJOURNAL OF FOOD SCIENCE, Issue 7 2010Kristen E. Matak Abstract:, The effect of electron beam (e-beam) radiation on the recovery of,Salmonella,serotypes Tennessee (ATCC 10722) and Typhimurium (ATCC 14028) in creamy peanut butter over a 14-d storage period at 22 °C was studied. Each,Salmonella,type was independently inoculated into peanut butter and subjected to e-beam doses that ranged from 0 to 3.1 kGy, confirmed by film dosimetry. After 2-, 4-, 6-, 8-, and 14-d of storage, microbial analyses were conducted. Survivors were recovered on growth and selective media using standard spread-plating methods. Microbial counts (CFU/g) were log-converted and differences were determined by ANOVA and Tukey's Honestly Significant Differences test. When samples were not e-beam-treated, there were no significant changes (P,> 0.05) in microbial numbers over time. In e-beamed samples, microbial numbers decreased over time; however, reductions were not always significant. Initial recovery rates (R-rates) 2 d after e-beam treatment were significantly different for the 2 strains of,Salmonella,and between recovery media (P,< 0.05); however, these differences did not persist for the remainder of the storage period (P,> 0.05) indicating that injured cells were not able to survive in the high-fat, low-water activity peanut butter environment. R-rates for both strains of,Salmonella,were maintained until day 14 when there were significant reductions in,Salmonella,Typhimurium (P,< 0.05). These results indicate that,Salmonella,Tennessee and,Salmonella,Typhimurium will survive in peanut butter when exposed to nonlethal doses of e-beam irradiation. Practical Application: Electron beam (e-beam) irradiation is an alternative to thermal processing; this technique inactivates microorganisms and insects that might be present in a food by generating radiation by accelerated electrons that inactivate organisms directly because of interaction with cell components and indirectly by producing free radicals that disrupt integrity of the cell membrane. E-beam radiation will reduce the number of probable microbiological hazards that could be present while the food remains generally unaffected in texture, taste, and nutritional value. A recent study showed e-beam irradiation to be effective at reducing both,Salmonella,Tennessee and Typhimurium in peanut butter by one log after exposure to less than 1 kGy, highlighting the need to explore this process further. [source] Contribution of electron precession to the study of perovskites displaying small symmetry departures from the ideal cubic ABO3 perovskite: applications to the LaGaO3 and LSGM perovskitesJOURNAL OF MICROSCOPY, Issue 1 2008J.-P. MORNIROLI Summary Electron microscopy and electron diffraction are well adapted to the study of the fine-grained, faulted pure and doped LaGaO3 and LSGM perovskites in which the latter is useful for fuel cell components. Because these perovskites display small symmetry departures from an ideal cubic ABO3 perovskite, many conventional electron diffraction patterns look similar and cannot be indexed without ambiguity. Electron precession can easily overcome this difficulty mainly because the intensity of the diffracted beams on the precession patterns is integrated over a large deviation domain around the exact Bragg condition. This integrated intensity can be trusted and taken into account to identify the ,ideal' symmetry of the precession patterns (the symmetry which takes into account both the position and the intensity of the diffracted beams). In the present case of the LaGaO3 and LSGM perovskites, the determination of the ,ideal' symmetry of the precession patterns is based on the observation of weak ,superlattice' reflections typical of the symmetry departures. It allows an easy and sure identification of any zone axes as well as the correct attribution of hkl indices to each of the diffracted beams. Examples of applications of this analysis to the characterizations of twins and to the identification of the space groups are given. This contribution of electron precession can be easily extended to any other perovskites or to any crystals displaying small symmetry departures. [source] Odontogenic ghost cell tumour with clear cell components: clear cell odontogenic ghost cell tumour?JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 6 2004Jung Hoon Yoon A case of odontogenic ghost cell tumour (OGCT) with clear cell components was encountered in the mandible of a 63-year-old man. The tumour revealed ameloblastomatous-type epithelial components accompanied by clusters of ghost cells and dentinoid juxtaposed to the odontogenic epithelium. In addition, some areas of the tumour tissue showed sheets and islands of clear, glycogen containing epithelial cells, which were separated by a thin fibrous connective tissue stroma. Both ameloblastic and clear cells exhibited positive immunoreactivities for cytokeratin 19 and AE1/3. It is not known whether this tumour represents a clear cell change of a pre-existing OGCT or a separate and distinct neoplasm derived de novo from the odontogenic epithelium. This tumour was given the term ,clear cell OGCT' because it captures the clear cell components, which is one of the most prominent distinguishing features of the tumour. [source] Cytological Alterations Produced by Sweet Potato Mild Speckling VirusJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2006C. F. Nome Abstract The potyvirus sweet potato mild speckling (SPMSV) has the biological properties and the coat protein sequence already described. In this work, cytological alterations and the intracellular localization in Ipomoea setosa and Ipomoea batatas was studied. The observations were carried out by means of transmission electron microscopy, complemented with immunogold techniques for the viral localization with SPMSV antiserum of local production. The observations carried out showed almost no alteration on cell components but the presence of cylindrical inclusion in the cytoplasm (bundles, laminate aggregates, and pinwheels, neither circles nor scrolls) belonging to the type-2 in the classification of Edwardson and Christie (Cylindrical Inclusions. Bulletin 894, 1996, pp. 1,11). Gold particles were localized in cytoplasms of all tissues of the leaf. [source] Carbon Metabolism Alterations in Sunflower Plants Infected with the Sunflower Chlorotic Mottle VirusJOURNAL OF PHYTOPATHOLOGY, Issue 5 2003M. C. Arias Abstract Sunflower chlorotic mottle virus (SuCMoV) causes chlorotic mottling symptoms and important growth reductions and yield losses in sunflower (Helianthus annuus L., cv. Contiflor 7). This paper describes the effects of SuCMoV on some aspects of carbon metabolism of sunflower plants. After symptoms became evident, CO2 fixation rates decreased, nevertheless, soluble sugars and starch increased in infected leaves. High H2O2 accumulation, lipid peroxidation and chlorophyll degradation were, like the other changes, observed only after symptom expression. Increased soluble carbohydrate accumulation was not related to changes in , -amylase (EC 3.2.1.1) activity, nor in the activities of enzymes associated with sugar import and hydrolysis such as invertase (EC 3.2.1.26) and sucrose synthase (EC 2.4.1.13), suggesting it did not derive from starch hydrolysis nor increased sugar import. Rather, it may derive from recycling of cell components associated with the development of oxidative damage. The physiological alterations caused by this virus share many common features with the development of senescence. [source] Migration of human and mouse primordial germ cells and colonization of the developing ovary: An ultrastructural and cytochemical study ,MICROSCOPY RESEARCH AND TECHNIQUE, Issue 6 2006Jaime Pereda Abstract This review is an account of the origin and migratory events of primordial germ cells until their settlement in the gonad before sexual differentiation in the human as well as mice. In this context, the morphodynamic characteristics of the migration of the primordial germ cells, the macromolecular characteristics of the extracellular matrix of the migratory pathway, and the factors involved in the germ cell guidance have been analyzed and discussed in the light of recent advances in this field, by means of immunocytochemical procedures. The events prior to gonadal morphogenesis and the origin of the somatic cell content of the human gonadal primordium have been also analyzed. In particular, evidences are presented showing that cells derived from the coelomic epithelium and mesenchyme are at the origin of the somatic components of the gonadal primordium, and that a mesonephric cell contribution to the generation of somatic cell components of the genital ridge in humans should be discarded due to the morphological stability of the different nephric structures during the period preceding the sexual differentiation of the gonad. Microsc. Res. Tech., 2006. © 2006 Wiley-Liss, Inc. [source] Astroblastoma with unusual signet-ring-like cell components: A case report and literature reviewNEUROPATHOLOGY, Issue 3 2002Yasuo Sugita We report a case of astroblastoma with unusual signet-ring-like cell components. A 33-year-old-woman presented with occasional partial seizures of the face. Radiological studies revealed an enhanced frontal mass lesion. At surgery, a gray, soft, well-circumscribed mass was seen and shelled out. Histologically, the tumor showed a perivascular arrangement and papillary-like patterns with compact cellularity. The tumor cells radiating from the hyalinized vessels showed broader, shorter, less tapered processes. A part of each tumor cell displayed prominent islands of signet-ring-like cells. Glial fibrillary acidic protein reaction revealed strongly positive staining of tumor cells and signet-ring-like cells. Eight years after the operation the patient remains well with no tumor recurrence. It remains to be determined whether, in this astroblastoma, the unusual signet-ring-like cell components were related to benign biological characteristics or to the tumor's low-grade form with incidental signet-ring-like cell appearance. [source] Histologically low-grade dedifferentiated liposarcoma of the retroperitoneumPATHOLOGY INTERNATIONAL, Issue 5 2001Masaharu Fukunaga A low-grade dedifferentiated liposarcoma in the retroperitoneum of a 52-year-old woman is described. The excised specimens contained six nodules of lipoma-like well-differentiated liposarcoma and a nodule of dedifferentiated liposarcoma. The latter was composed predominantly of loosely arranged, benign-appearing spindle cells and fat cells. A small number of cells with irregularly shaped nuclei were scattered. There were no mitotic figures. The fat cells showed slight variation of size and shape, and a few multivacuolated lipoblasts were found. The spindle cell areas occupied approximately 60% of the tumor. The stroma was somewhat fibrous and myxoid and no dense collagenous matrix was found. The stroma vascularity was not prominent. Immunohistochemically, the spindle cells were positive for vimentin but negative for S-100 protein, desmin, muscle actin, and , -smooth muscle actin. Follow up for 5 months showed no evidence of recurrence or metastasis. The tumor, in which the benign-appearing spindle cell component was predominant, was considered to be a low-grade dedifferentiated liposarcoma. Close and long-term follow up is required. In retroperitoneal lipoma-like well-differentiated liposarcomas, spindle cell components like the present tumor, which represent dedifferentiation, should not be overlooked. [source] | ||||||||||||||||||||||||||||||||||