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61.
62.
Steven D. Herman Paul D. Radecki Arnold C. Friedman Dina F. Caroline Parvati Ramchandani Louis M. Marmon Julieta D. Grosh 《Urologic radiology》1988,9(1):225-227
Sonography detected a paraaortic pulsatile tubular mass in a patient 10 years after “stump” nephrectomy, which was subsequently confirmed as a renal artery-renal vein fistula by computed tomography, angiography, and laparotomy. 相似文献
63.
Cosma A Bühler S Nagaraj R Staib C Hammarin AL Wahren B Goebel FD Erfle V Sutter G 《Clinical and diagnostic laboratory immunology》2004,11(2):406-410
Vaccination against smallpox is again considered in order to face a possible bioterrorist threat, but the nature and the level of the immune response needed to protect a person from smallpox after vaccination are not totally understood. Therefore, simple, rapid, and accurate assays to evaluate the immune response to vaccinia virus need to be developed. Neutralization assays are usually considered good predictors of vaccine efficacy and more informative with regard to protection than binding assays. Currently, the presence of neutralizing antibodies to vaccinia virus is measured using a plaque reduction neutralization test, but this method is time-consuming and labor-intensive and has a subjective readout. Here, we describe an innovative neutralization assay based on a modified vaccinia virus Ankara (MVA) vector expressing the green fluorescent protein (MVA-gfp). This MVA-gfp neutralization assay is rapid and sensitive and has a high-throughput potential. Thus, it is suitable to monitor the immune response and eventually the efficacy of a large campaign of vaccination against smallpox and to study the vector-specific immune response in clinical trials that use genetically engineered vaccinia viruses. Most importantly, application of the highly attenuated MVA eliminates the safety concern in using the replication-competent vaccinia virus in the standard clinical laboratory. 相似文献
64.
Social disparities in health persist into old age, and differences in psychophysiological responsivity may contribute to this pattern. We assessed whether higher socioeconomic status (SES) is associated with attenuated cardiovascular and neuroendocrine responses elicited by cognitive tasks in old age. We tested 132 community-dwelling men and women aged 65-80 years, divided on the basis of educational attainment into higher and lower SES groups, and compared them with 26 higher educated participants aged 27-42 years. Blood pressure, hemodynamic variables and salivary cortisol were assessed in response to the performance of three cognitive tasks, and then during recovery. Older groups showed smaller heart rate and larger cortisol changes than younger participants. Post-task recovery in heart rate, stroke volume, pre-ejection period, and systolic blood pressure was greatest in the younger group, least in the older/lower education group, and intermediate in the older/higher education group. SES did not influence the increased cortisol responsivity of older participants. The results are consistent with the notion that higher SES protects against age-related changes in cardiovascular response profiles, particularly during recovery. 相似文献
65.
66.
Summary Guinea pig embryo (GPE) cells showed different degrees of susceptibility to human adenovirus types as determined by virus infectivity assay and electron microscopic examination. Adenovirus 2 and 5 induced extensive cellular changes and produced high titers of infectious virus in GPE cells as in human cells. Mature progeny virus and protein crystals were observed in both cell types. Adenovirus 7 induced some cellular changes in GPE cells but only a small number of cells yielded progeny virus as determined by electron microscopy. Adenovirus 3, 8 and 31 induced some cellular changes but no progeny virus was found under electron microscopic examination. Characteristic fibers were observed in nuclei of adenovirus 31 infected cells. The ability of human adenovirus 2 and 5 to replicate in GPE cells is an example of an unusual cross-species biological property of certain adenovirus types. This property may be useful as a biological marker for these virus types.With 8 Figures 相似文献
67.
Chwieralski CE Schnurra I Thim L Hoffmann W 《American journal of respiratory cell and molecular biology》2004,31(5):528-537
Injured areas of the respiratory epithelium are subject to rapid repair by the migration of adjacent epithelial cells, a process termed "restitution". Rapid re-epithelialization is promoted by interactions between migrating cells and the extracellular matrix proteins. Furthermore, epidermal growth factor (EGF) as well as trefoil factor family (TFF) peptides are well known regulators of epithelial restitution due to their motogenic effects. Migration of the human bronchial epithelial cell line BEAS-2B in modified Boyden chambers was used as a model system for airway restitution. EGF or recombinant human TFF2 or TFF3 showed mainly chemotactic activity. The motogenic response was strictly dependent upon a haptotactic substrate, but to different degrees. EGF induced phosphorylation of extracellular signal-regulated kinases (ERK) 1/2, c-Jun-N-terminal kinase, p38, Akt, and p70S6K in BEAS-2B cells. Using specific inhibitors, the signaling cascades responsible for the motogenic response were shown to differ drastically when EGF was compared with TFF2. The motogenic effect of TFF2 was previously demonstrated to depend on ERK1/2 and protein kinase C activation; whereas the EGF-triggered motogenic response was completely independent of ERK1/2 activation but sensitive to the inhibition of phosphoinositide 3-kinase, p38, protein kinase C, or nuclear factor kappaB. However, the motogenic effects of EGF and TFF2 are additive. These data suggest that luminal EGF and TFF peptides can act synergistically in the human respiratory epithelium to enhance rapid repair processes in the course of diseases such as asthma. 相似文献
68.
69.
Caroline Vandevyver Nadja Mertens Peter van den Elsen Robert Medaer Jef Raus Jingwu Zhang 《European journal of immunology》1995,25(4):958-968
Myelin basic protein (MBP)-reactive T cells are thought to play an important role in the pathogenesis of multiple sclerosis (MS). In some patients with MS, these autoreactive T cells display a limited heterogeneity in their epitope recognition and T cell receptor (TCR) variable (V) gene usage. These individual-dependent properties of MBP-reactive T cells have led to the speculation that they may represent clonal expansion in vivo in some MS patients. In the present study, 51 MBP-reactive T cell clones derived from patients with MS and healthy individuals were examined for their epitope recognition and the TCR Vα and Vβ gene rearrangements. The V gene junctional region sequences of identified α and β genes were further analyzed to probe their clonal origins, as the sequences are unique for individual clones. Our data showed that 26 clones derived from nine patients with MS shared a predominant reactivity to the immunodominant regions of MBP, 84–102, 110–129 and 143–168, and used various TCR Vα and Vβ rearrangements. The V gene usage of the clones was restricted to certain Vα Vβ combination(s) in a given MS patient, but varied among different patients. The sequence analysis revealed that the clones generated from a given patient shared a limited or a single junctional region sequence pattern(s), indicating their oligoclonal or monoclonal origin(s). In contrast, 25 MBP-reactive T cell clones derived from normal individuals exhibited unfocused epitope recognition and V gene usage. Thus, the limited heterogeneity of MBP-reactive T cells in their structural and functional charactertistics reflects their clonal expansion in vivo in some patients with MS. 相似文献
70.
Oral administration of insulin conjugated to the B chain of cholera toxin (CTB-insulin) in non-obese diabetic (NOD) mice results in diabetes prevention. We investigated the respective contributions of L-selectin (CD62L) and alpha4-integrin pathways during CTB-driven tolerance. Purified CD62L+CD4+ cells from CTB-insulin fed mice significantly reduced the capacity of diabetogenic T cells to transfer diabetes in syngeneic recipients. In vivo antibody blockade of fed animals during adoptive co-transfer experiments indicated that both CD62L and alpha4-integrins pathways were necessary to develop a protective response after oral tolerance induction. In contrast, when antibodies were given to recipient mice, only CD62L was critical for the protection. In vitro stimulated CD62L+CD4+ cells from the spleen of fed animals secreted lower amounts of IL-4 and IL-10 but comparable levels of TGFbeta than CD62L-cells. A reduced IFN-gamma production between the two cell subsets was specifically observed in CTB-insulin fed mice. Furthermore, antibody treatments induced changes in T-cell migration to the spleen, mesenteric and pancreatic lymph nodes. The protective effect was also associated with migration of regulatory T cells into pancreatic islets. Taken together, our results suggest that L-selectin and alpha4-integrin have distinct but complementary roles in the generation and function of regulatory CD4+ T cells following CTB-insulin administration. 相似文献