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141.
C. elegans ORFeome Version 3.1: Increasing the Coverage of ORFeome Resources With Improved Gene Predictions 总被引:1,自引:0,他引:1 下载免费PDF全文
Philippe Lamesch Stuart Milstein Tong Hao Jennifer Rosenberg Ning Li Reynaldo Sequerra Stephanie Bosak Lynn Doucette-Stamm Jean Vandenhaute David E. Hill Marc Vidal 《Genome research》2004,14(10B):2064-2069
The first version of the Caenorhabditis elegans ORFeome cloning project, based on release WS9 of Wormbase (August 1999), provided experimental verifications for ~55% of predicted protein-encoding open reading frames (ORFs). The remaining 45% of predicted ORFs could not be cloned, possibly as a result of mispredicted gene boundaries. Since the release of WS9, gene predictions have improved continuously. To test the accuracy of evolving predictions, we attempted to PCR-amplify from a highly representative worm cDNA library and Gateway-clone ~4200 ORFs missed earlier and for which new predictions are available in WS100 (May 2003). In this set we successfully cloned 63% of ORFs with supporting experimental data (“touched” ORFs), and 42% of ORFs with no supporting experimental evidence (“untouched” ORFs). Approximately 2000 full-length ORFs were cloned in-frame, 13% of which were corrected in their exon/intron structure relative to WS100 predictions. In total, ~12,500 C. elegans ORFs are now available as Gateway Entry clones for various reverse proteomics (ORFeome v3.1). This work illustrates why the cloning of a complete C. elegans ORFeome, and likely the ORFeomes of other multicellular organisms, needs to be an iterative process that requires multiple rounds of experimental validation together with gradually improving gene predictions. 相似文献
142.
Gerhold K Blümchen K Bock A Seib C Stock P Kallinich T Löhning M Wahn U Hamelmann E 《The Journal of allergy and clinical immunology》2002,110(1):110-116
BACKGROUND: Contact with immunomodulatory factors, such as LPS, in early infancy is associated with decreased allergen sensitization. OBJECTIVE: We sought to study the effects of systemic or airway exposure with LPS on the development of allergen sensitization, eosinophilic airway inflammation, and increased in vivo airway reactivity (AR) in a mouse model. METHODS: BALB/c mice were systemically sensitized with ovalbumin (OVA) plus adjuvant on days 1 and 14 and challenged through the airways with allergen on days 34 to 36. We performed measurement of OVA-specific IgE serum levels, in vitro T(H)2 cytokine production, differential cell counts in bronchoalveolar lavage fluids, and assessment of in vivo AR to inhaled methacholine by means of barometric whole-body plethysmography. RESULTS: Systemic LPS administration before OVA sensitization reduced OVA-specific IgE serum levels (426 +/- 76 vs 880 +/- 104 U/mL, P <.01), T(H)2 cytokine production by splenic mononuclear cells (IL-4: 0.08 +/- 0.01 vs 0.17 +/- 0.01 ng/mL; IL-5: 1.98 +/- 0.52 vs 4.11 +/- 0.54 ng/mL; P <.01), and extent of airway eosinophilia (total cell counts: 93 vs 376 x 10(3)/mL; eosinophils: 23% vs 51%; P <.01) compared with that in OVA-sensitized mice. Local LPS administration to sensitized mice before airway allergen challenges particularly induced IFN-gamma production by peribronchial lymph node cells in vitro (1718 +/- 315 vs 483 +/- 103 ng/mL, P <.01) associated with reduced airway eosinophilia compared with that seen in OVA-sensitized mice. Development of increased AR was not affected by systemic or local LPS exposure. Inhibitory effects of LPS on allergen sensitization and eosinophilic airway inflammation were inhibited by administration of anti-IL-12 antibodies before LPS exposure. CONCLUSION: These data indicate that local and systemic application of LPS modulates systemic and local T(H)1/T(H)2 immune responses in a distinct but similarly IL-12-dependent mode. 相似文献
143.
Le Caignec C De Mas P Vincent MC Bocéno M Bourrouillou G Rival JM David A 《American journal of medical genetics. Part A》2005,(2):175-180
Thirty patients have been described with cytogenetically visible deletion of the short arm of chromosome 6. However, subtelomeric 6p deletion detected by subtelomeric specific probes has been reported only twice. We report two new patients with terminal 6p deletion detected by subtelomeric screening using fluorescence in situ hybridization (FISH). The two patients exhibited mental retardation, ocular abnormalities, hearing loss, and a characteristic facial appearance. Detailed FISH analyses with probes covering the distal 6p25 region estimated the size of the terminal deletions to approximately 5.5 Mb and approximately 4.8 Mb. Array-based comparative genomic hybridization (array CGH) was used to confirm the cryptic deletions. Most patients with subtelomeric defects lack a characteristic phenotype. However, some of the subtelomeric deletions result in a specific phenotype, which can direct the clinician towards the diagnosis. Submicroscopic 6p deletion appears to be a recognizable clinical phenotype, and this region should be thoroughly investigated with FISH probes, including at least a subtelomeric 6p probe and a probe covering FOXC1, for patients presenting with a characteristic facial appearance, ocular abnormalities, predominantly anterior-chamber eye defects, hearing loss, and mental retardation. 相似文献
144.
Pierre Chatelain Patrick Robberecht Philippe De Neef Monique Deschodt-Lanckman Wolfgang König Jean Christophe 《Pflügers Archiv : European journal of physiology》1980,388(1):21-27
The exact positions of microelectrodes used to measure thePO2 in the cerebral cortex of the rat were determined by staining the tissue with Alcian Blue. The measurement sites were subsequently located under a light microscope and correlated with the capillary and cellular arrangement of the cortex. The microelectrodes used for thePO2 measurements were made of gold glass fibers; the Alcian Blue was injected hydrostatically through a micropipette attached to thePO2 microelectrode. The sites where dye had been deposited were seen under a light microscope as green blue spots about 100 m in diameter. The capillaries were visualized by silver nitrate perfusion. Differences between the localPO2 values in the neo- and the archeocortex were found. In the neocortex the meanPO2 was 31 mm Hg, capillary volume 1.6%, capillary surface area 980/mm2, capillary length 13.5/mm; whereas in the archeocortex these values where 21 mm Hg, 0.9%, 820/mm2 and 9.4/mm respectively. These data indicate a relationship between the microcirculatory transport system and the local oxygen tension and provide further evidence that the meanPO2 level tends to decrease when moving from the surface into the archeocortex.Supported by the Deutsche ForschungsgemeinschaftReported in part at the 3rd Symposium of ISOTT, Cambridge, GB, 1977; and at the 27th International Congress of Physiological Sciences, Paris, France, 1977 相似文献
145.
Sarcomatoid carcinomas involving the intestinal tract are rare and usually associated with poor prognosis. We report a case of sarcomatoid carcinoma of the ileum, diagnosed in a 61-year-old man. The patient presented with acute intestinal occlusion. Surgical resection of the ileum was performed. At macroscopic examination, two large polypoid masses were found. Frozen section examination suggested the diagnosis of malignant stromal tumor. At histological examination, both tumors were formed by pleiomorphic, large spindle cells, presenting numerous mitoses and marked nuclear atypia. Immunohistochemical examination showed that tumor cells coexpressed vimentin and epithelial markers (cytokeratins, EMA). The final diagnosis was monomorphic sarcomatoid carcinoma. The patient deceased with metastatic disease after 3 months of follow-up. This report underlines the potential diagnostic problems raised by this unusual type of carcinoma and emphasizes the role of immunohistochemistry in assessing the correct diagnosis. 相似文献
146.
Recombinant VP9-based enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies to Banna virus (genus Seadornavirus) 总被引:1,自引:0,他引:1
Mohd Jaafar F Attoui H Gallian P Isahak I Wong KT Cheong SK Nadarajah VS Cantaloube JF Biagini P De Micco P De Lamballerie X 《Journal of virological methods》2004,116(1):55-61
Banna virus (BAV, genus Seadornavirus, family Reoviridae) is an arbovirus suspected to be responsible for encephalitis in humans. Two genotypes of this virus are distinguishable: A (Chinese isolate, BAV-Ch) and B (Indonesian isolate, BAV-In6969) which exhibit only 41% amino-acid identity in the sequence of their VP9.The VP7 to VP12 of BAV-Ch and VP9 of BAV-In6969 were expressed in bacteria using pGEX-4T-2 vector. VP9 was chosen to establish an ELISA for BAV, based mainly on two observations: (i). VP9 is a major protein in virus-infected cells and is a capsid protein (ii). among all the proteins expressed, VP9 was obtained in high amount and showed the highest immuno-reactivity to anti-BAV ascitic fluid.The VP9s ELISA was evaluated in three populations: French blood donors and two populations (blood donors and patients with a neurological syndrome) from Malaysia, representing the region where the virus was isolated in the past.The specificity of this ELISA was >98%. In mice injected with live BAV, the assay detected IgG-antibody to BAV infection 21 days post-injection, which was confirmed by Western blot using BAV-infected cells.The VP9 ELISA permits to determine the sero-status of a population without special safety precautions and without any requirements to propagate the BAV. This test should be a useful tool for epidemiological survey of BAV. 相似文献
147.
148.
A panel of antibodies for the immunostaining of Bouin's fixed bone marrow trephine biopsies. 下载免费PDF全文
J L Gala F Chenut K B Hong J Rodhain P Camby M Philippe J M Scheiff 《Journal of clinical pathology》1997,50(6):521-524
AIMS: To assess a panel of antibodies on Bouin's fixed bone marrow trephine (BMT) biopsies. These biopsies are widely used in routine diagnosis of various haematological malignancies and may be the sole material available in many centres; however, information regarding the immunostaining of this material is lacking. METHODS: Biopsies were taken from 72 patients presenting with various haematological malignancies (leukaemia, 38; lymphoma, 14; multiple myeloma, 20). A panel of antibodies was assessed on Bouin's fixed BMT biopsies by the alkaline phosphatase-antialkaline phosphatase method. RESULTS: Three B (MB2, LN-2, Ki-B5) and two T cell lineage antibodies (UCHL-1, CD3-r) reliably identified lymphoid cells, while MPO-r, Leu-M1/CD15, and KP-1/CD68 recognised cells from the myeloid or histiocytic/macrophage series. Reed-Sternberg cells were stained by LN-2, Leu-M1, and CD30. Antibodies specific for plasma cells (VS38) and hairy cells (DBA.44) gave a variable pattern of staining. Among the proliferation markers, proliferative cell nuclear antigen but not Ki-67 related antibodies were effective. CONCLUSION: This study presents a panel of antibodies with reactivity not restricted to common fixatives that are also suitable for Bouin's fixed BMT biopsies. 相似文献
149.
Nathalie Sints-Zydowicz Quang Tho Pham Jacque Dubois Philippe Michaud 《Macromolecular chemistry and physics.》1997,198(7):2017-2026
In depth study of low molecular weight poly(imide-amide)s (PIA) obtained by copolycondensation of 4,4′-methylenedi(phenyl isocyanate), trimellitic anhydride and benzoic acid by 1H and 13C NMR spectroscopy and size-exclusion chromatography allows the determination of their absolute number-average molecular weights M?n, abs. Viscosimetric measurements reveal that, dissolved in N-methyl-2-pyrrolidone, these low molecular weight PIAs should be semi-rigid because of the presence of very short crystalline chains. By using the semi-empirical Fox-Flory relation, the extrapolated glass transition temperature equals 300°C for high molecular weight. 相似文献
150.
Killing of Aspergillus fumigatus by alveolar macrophages is mediated by reactive oxidant intermediates 下载免费PDF全文
Philippe B Ibrahim-Granet O Prévost MC Gougerot-Pocidalo MA Sanchez Perez M Van der Meeren A Latgé JP 《Infection and immunity》2003,71(6):3034-3042
Phagocytosis and mechanisms of killing of Aspergillus fumigatus conidia by murine alveolar macrophages (AM), which are the main phagocytic cells of the innate immunity of the lung, were investigated. Engulfment of conidia by murine AM lasts 2 h. Killing of A. fumigatus conidia by AM begins after 6 h of phagocytosis. Swelling of the conidia inside the AM is a prerequisite for killing of conidia. The contributions of NADPH oxidase and inducible nitric oxide synthase to the conidicidal activity of AM were studied using AM from OF1, wild-type and congenic p47phox(-/-) 129Sv, and wild-type and congenic iNOS(-/-) C57BL/6 mice. AM from p47phox(-/-) mice were unable to kill A. fumigatus conidia. Inhibitors of NADPH oxidase that decreased the production of reactive oxidant intermediates inhibited the killing of A. fumigatus without altering the phagocytosis rate. In contrast to NADPH oxidase, nitric oxide synthase does not play a role in killing of conidia. Corticosteroids did not alter the internalization of conidia by AM but did inhibit the production of reactive oxidant intermediates and the killing of A. fumigatus conidia by AM. Impairment of production of reactive oxidant intermediates by corticosteroids is responsible for the development of invasive aspergillosis in immunosuppressed mice. 相似文献