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61.
Bissinger AL Brugger J Grigoleit GU Gründemann C Hebart H Einsele H Jahn G 《Viral immunology》2005,18(3):534-538
To monitor the frequencies of virus-specific cytotoxic T lymphocytes (CTLs), FACS analyses were performed detecting lymphocyte-specific surface molecules and tetramer binding, as marker for peptide-specificity. Aim of this investigation was to establish an alternative protocol for the quantification of virus-specific CTLs using tetramer binding and microscopic analyzing. The frequencies of HCMV-pp65-peptide-specific CTLs in the blood of eight different HLA-A*0201-positive, HCMV-IgG antibody-positive donors were analyzed with both methods. Using FACS analyses, a median of 0.8% and, using the microscopic analyses, a median of 3.0% was detected in the CD3+CD8+ cells. After enrichment of HCMV-pp65-peptide-specific CTLs using the interferon-gamma secretion assay followed by expansion in cell culture, a median of 90.6% using FACS analyses and a median of 87.1% using the microscopic analyses was detected. Thus, the staining protocol presented in this investigation is an alternative approach to detect and to quantify virus-specific CTLs in low as well as in high frequencies. 相似文献
62.
U. Grüsser-Cornehls P. Böhm 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,72(1):29-36
Summary Horizontal optokinetic nystagmus (OKN) evoked by a random dot pattern moving at a constant speed around the animal was investigated in wild-type mice and Weaver mutants (cerebellar impairment) by means of chronically implanted EOG-electrodes. The shape of OKN in the homozygotic Weaver mouse was clearly different from that in normal mice. The OKN in the mutant showed inconstant velocity during the slow phase. Nystagmus frequency of the mutant was significantly below that of normal controls for velocities of 1.4 to 25 degrees · s-1. In one group of normals the mean slow-phase gain was relatively constant for stimulus angular velocities between 1.4 and 15 degrees · s-1 and declined thereafter. In a second group the mean slow-phase gam decreased gradually between stimulus angular velocities from 1.4 to 15 degrees · s-1 and thereafter with a steeper slope. In mutants gain decreases with increasing stimulus velocity over the entire range tested (1.4 to 42 degrees · s-1). Normals and mutants with one eye occluded exhibited strong OKN when the pattern was moved in a temporonasal direction; little response was obtained by stimuli moving in a naso-temporal direction. 相似文献
63.
Amygdala-prefrontal coupling depends on a genetic variation of the serotonin transporter 总被引:12,自引:0,他引:12
Heinz A Braus DF Smolka MN Wrase J Puls I Hermann D Klein S Grüsser SM Flor H Schumann G Mann K Büchel C 《Nature neuroscience》2005,8(1):20-21
Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression. 相似文献
64.
65.
Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases 总被引:5,自引:2,他引:5
Huang JQ; Trasler JM; Igdoura S; Michaud J; Hanal N; Gravel RA 《Human molecular genetics》1997,6(11):1879-1885
Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative
diseases resulting from the inability to catabolize GM2 ganglioside by
beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit
(Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B
(beta beta homodimer) is also defective in Sandhoff disease. We previously
developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs)
mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff)
mice succumb to a profound neurodegenerative disease by 4-6 months of age.
Here we find that neuron death in Hexb-/- mice is associated with apoptosis
occurring throughout the CNS, while Hexa-/- mice were minimally involved at
the same age. Studies of autopsy samples of brain and spinal cord from
human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances,
in keeping with the severe expression of both diseases. We suggest that
neuron death is caused by unscheduled apoptosis, implicating accumulated
GM2 ganglioside or a derivative in triggering of the apoptotic cascade.
相似文献
66.
K Rosenl?f F Fyhrquist C Gr?nhagen-Riska T B?hling M Haltia 《Acta medica Scandinavica》1985,218(5):481-485
We examined eight cerebellar haemangioblastoma tumours from eight patients, aged 16-63 years, 5 females and 3 males. Preoperative haemoglobin values exceeded 180 g/l in four patients, and 150 g/l in four. All high Hb values were normalized upon surgical removal of the tumours. All tumours contained scattered cells which stained positively with antisera against pure human urinary erythropoietin and plasma renin substrate. We conclude that cerebellar haemangioblastomas produce immunoreactive erythropoietin, which shares common antigenic determinants with renin substrate. 相似文献
67.
In vitro phosphorylation of SV40 large T antigen 总被引:20,自引:0,他引:20
Phosphorylation of simian virus 40 large T antigen (large T) was investigated in vitro. "Autophosphorylation" of large T resulted in the modification of Ser106, Ser112, Ser123, Thr124, either Ser676, Ser677, or Ser679, and Thr701. All of these residues were also found to be phosphorylated in vivo. Reaction of large T with purified casein kinase I resulted in phosphorylation of Ser123, possibly Thr124, and either Ser676, Ser677, or Ser679, while purified casein kinase II phosphorylated Ser106 and possibly Ser112. Submolar amounts of phosphate were transferred to large T indicating that only a fraction of large T served as substrate for the casein kinases. Removal of serine-bound phosphate did not affect the subsequent autophosphorylation or phosphorylation by casein kinase I and II. No phosphorylation at in vivo sites was observed with the cAMP-, cGMP-, or Ca2+/phospholipid-dependent protein kinases, or with the protease-activated kinase I and II. 相似文献
68.
69.
Hemispheric asymmetry of feedback-related potentials in a positioning task: comparison of right- and left-handed subjects 总被引:1,自引:0,他引:1
G Grünewald E Grünewald-Zuberbier R G?tzinger J Mewald H Schuhmacher 《Biological psychology》1987,24(3):209-223
Previous research has demonstrated that delayed nonverbal information feedback (IF) about the correctness of a positioning movement is preceded by a contingent negative variation (CNV) which is larger over the right hemisphere independent of movement side. It was hypothesized that this asymmetry is a manifestation of functional hemispheric specialization, and that, therefore, the distribution of the differences between CNV amplitude measures of the two hemispheres should be different in right-handed and left-handed subjects. The latter group should show a mean asymmetry score closer to zero, and a larger between-subject variance of the asymmetry scores. The present investigation was intended to test these assumptions in samples of rigorously defined right-handers (n = 12) and left-handers (n = 8). The results revealed the expected group differences of the CNV asymmetry scores. In addition, the P1-N1 peak-to-peak amplitude of the IF-evoked potentials was similarly lateralized as the pre-IF CNV and showed the same group differences. In contrast, the handedness groups did not differ in the contralateral lateralization of the movement-related potential shift in the same task. 相似文献
70.
Huber M Wierrani F Böhm G Hauck H Lintner F Grünberger W 《Pathology, research and practice》1999,195(1):59-64
We report an unusual case of a nodular variation of pulmonary endometriosis. To our knowledge, there is no previous report on a morphological investigation of this entity. The etiology of this rare condition is still a matter of discussion. The well-circumscribed nodular mass is composed of cells identical to, or closely resembling, those of endometrial stroma containing sparse cysts and glands. Immunohistochemically, the cells showed an extensive co-expression of cytokeratin AE1/AE3 and vimentin and were highly positive for progesterone receptor (PRICA) and estrogen receptor (ERICA). Cells lining the cysts and glands as a monolayer were reactive for Ber-Ep4, cytokeratin Pan and cytokeratin AE1/AE3 and negative to all other markers used including PRICA and ERICA. The differential diagnosis of this entity included fibrous tumor of the pleura and metastatic low-grade-endometrial-stromal-sarcoma. The morphological findings are correlated with immunohistochemical studies and results of cell image analysis. This study details the clinicopathological features of the nodular variation of pulmonary endometriosis. 相似文献