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21.
Matthias Lngin Bruno Reichart Stig Steen Trygve Sjberg Audrius Paskevicius Qiuming Liao Guangqi Qin Maren Mokelke Tanja Mayr Julia Radan Lara Issl Ines Buttgereit Jiawei Ying Ann Kathrin Fresch Alessandro Panelli Stefanie Egerer Andrea Bhr Barbara Kessler Anastasia Milusev Riccardo Sfriso Robert Rieben David Ayares Peter J. Murray Reinhard Ellgass Christoph Walz Nikolai Klymiuk Eckhard Wolf Jan‐Michael Abicht Paolo Brenner 《Xenotransplantation》2021,28(1):e12636
22.
Natalia?S.?Zhdanova Tatjana?V.?Karamisheva Julia?Minina Natalia?M.?Astakhova Peter?Lansdorp Makoto?Kammori Nikolai?B.?Rubtsov Jeremy?B.?SearleEmail author 《Chromosome research》2005,13(6):617-625
Sorex araneus and Sorex granarius are sibling species within the Sorex araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. araneus and S. granarius revealed differences between chromosomes and between species. In S. araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. araneus. This suggests that S. araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals. 相似文献
23.
Maria Svetlova Ljudmila Solovjeva Grigory Stein Claude Chamberland Baldev Vig Nikolai Tomilin 《Chromosome research》1994,2(1):47-52
Recentin situ hybridization studies suggested that within the range of 0.1–1.0 Mb, human interphase chromosomes follow a random walk model (i.e. they behave as flexible polymers without major constraints). However, chromosome structure may differ in the G1, S, and G2 phases, and phase-specific constraints may be masked if the chromosome analysis does not discriminate between the phases. Therefore, using confocal microscopy, we examined the structure of S-phase chromosomes labelled with 5-iododeoxyuridine after prolonged treatment with 5-fluorodeoxyuridine. In the S-phase, labelled 0.32 µ chromosome fibres mostly appear as semi-circles with an average diameter of 0.83 ±0.03 µ. These semi-circles are joined together to form different 3D structures, and two semicircles frequently adopt s- or-like conformations involving about 2.5 µ of the chromosome contour length (L). Morphometric analysis of the S-phase fibres suggests that our data fit both the random flexible polymer model and also a model in which two constrained semi-circles are attached to each other by a flexible joint, thus eliminating constraints at long distances (L more than 2 µ). 相似文献
24.
Induction of cytotoxic T-cell responses by gene gun DNA vaccination with minigenes encoding influenza A virus HA and NP CTL-epitopes. 总被引:6,自引:0,他引:6
A Fomsgaard H V Nielsen N Kirkby K Bryder S Corbet C Nielsen J Hinkula S Buus 《Vaccine》1999,18(7-8):681-691
Cytotoxic T-lymphocyte (CTL) response is an important component of anti-viral immunity. CTLs are specific to short peptides presented by MHC-I molecules and immunisation with the exact peptide sequence introduced in the cytosol is therefore a minimal approach, which potentially affords a high degree of controllability. We have examined the induction of murine CTL's by this approach using DNA plasmid minigene vaccines encoding known mouse K(k) minimal CTL epitopes (8 amino acids) from the influenza A virus hemagglutinin and nucleoprotein. We here report that such an approach is feasible and that wild type influenza virus flanking amino acid sequences can influence the CTL response but are not essential for optimal CTL induction. We also examined the effect of different new amino acid sequences flanking the CTL epitopes. In one version, two CTL epitopes were linked together as 'string of beads'. This did not improve CTL induction. In another version, one CTL epitope was inserted into a known T-helper protein (HBsAg). This did significantly augment the response probably due to immunological help from HBsAg Th epitopes. Finally, the CTL inducing minigene DNA vaccines were compared with Flu-induced CTL responses and tested for their protective effect against a lethal influenza A virus infection in mice and no effect was found. We conclude that a specific and highly directed CTL induction is possible by unlinked minigene DNA immunisation, but that CTL induction solely is not always sufficient to provide protection. 相似文献
25.
26.
Rainov Nikolai G. Dobberstein Karl-Ulrich Bahn Hannes Holzhausen Hans-Jürgen Lautenschläger Christine Heidecke Volkmar Burkert Winfried 《Journal of neuro-oncology》1997,35(1):13-28
Despite the use of multimodal therapy, higher-grade glioma is stilluniformly fatal in the adult population. There is a considerable differencebetween the length of survival in each given patient, even within the sametumor type and malignancy grade group, suggesting that there are factorsthat might differentially influence outcome. To identify such factors, 107patients with anaplastic or malignant glioma were retrospectivelyinvestigated. Clinical parameters and paraclinical data on the p53, mdm2,and EGFR genes at the DNA or protein level were evaluated by univariateanalysis and Cox proportional hazards regression modeling. Kaplan-Meiersurvival estimation demonstrated that immunohistochemical positivity formdm2 protein in patients with anaplastic astrocytoma or with glioblastomamultiforme was associated with a shorter survival time (p = 0.02).P53 gene mutations and immunopositivity for the epidermal growth factorreceptor (EGFR) protein were not significantly related to poor prognosis.The Cox proportional hazards model revealed immunohistochemical positivityfor p53, mdm2, or for both of them, the presence of postoperativeirradiation, and the extent of surgical resection of tumor to be variablessignificantly associated with prolonged survival. EGFR overexpression, ageover 60 years, and Karnofsky performance score below 40 points did notsignificantly shorten survival time. In conclusion, the present studyidentified immunohistochemically detected mdm2-protein overexpression as astatistically significant negative prognostic parameter in patients bearinganaplastic or malignant glioma. Association analysis of variables revealed apossible correlation between mdm2 and p53, which is also consistent with thebiological interaction mode of both proteins in vivo. 相似文献
27.
Ariane S?ling Mirko Sackewitz Michael Volkmar Daniel Schaarschmidt Roland Jacob Hans-Jürgen Holzhausen Nikolai G Rainov 《Clinical cancer research》2005,11(1):249-258
PURPOSE: The identification of new molecular markers in astrocytic tumors may help to understand the biology of these tumors in more detail. Informative tumor markers may represent prognostic factors for response to therapy and outcome as well as potential targets for novel anticancer therapies. EXPERIMENTAL DESIGN: Tumor-associated antigens were identified by immunoscreening of a human glioma cDNA expression library with allogeneic sera from patients with diffuse astrocytoma (WHO grades 2-4). The expression of one of the identified antigens, the replication licensing factor minichromosome maintenance protein 3 (MCM3), was analyzed by immunohistochemistry in 142 primary and 27 recurrent astrocytomas (WHO grades 2-4). In addition, 98 serum specimens from patients with primary and secondary brain malignancies and 30 serum specimens from healthy controls were examined by serologic immunoscreening for immunoreactivity with MCM3. RESULTS: MCM3 is overexpressed in human astrocytic tumors and elicits a cancer-restricted humoral immune response in 9.3% (9 of 97) of patients with brain tumors (n = 95) and brain metastases (n = 2) but not in healthy controls. Expression of MCM3 in diffuse astrocytoma is significantly associated with age (P < 0.001), histologic grade (P < 0.001), time to recurrence (P = 0.01), and expression of the proliferation marker Ki-67 (P < 0.001) but not with sex (P = 0.800). Univariate and multivariate Cox regression analysis confirmed MCM3 expression as an independent predictor of poor outcome in astrocytoma patients (P < 0.001 for both). CONCLUSIONS: MCM3 may represent a glioma-associated antigen with significant prognostic role as well as have some potential as a target for cancer-directed therapy. 相似文献
28.
29.
Nikolai Kiesel Florian Blaser Uro? Deli? David Grass Rainer Kaltenbaek Markus Aspelmeyer 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(35):14180-14185
The coupling of a levitated submicron particle and an optical cavity field promises access to a unique parameter regime both for macroscopic quantum experiments and for high-precision force sensing. We report a demonstration of such controlled interactions by cavity cooling the center-of-mass motion of an optically trapped submicron particle. This paves the way for a light–matter interface that can enable room-temperature quantum experiments with mesoscopic mechanical systems. 相似文献
30.
Maciej Cabanski Brett Fields Stephanie Boue Natalia Boukharov Hector DeLeon Natalie Dror Marcel Geertz Emmanuel Guedj Anita Iskandar Ulrike Kogel Celine Merg Michael J. Peck Carine Poussin Walter K. Schlage Marja Talikka Nikolai V. Ivanov Julia Hoeng Manuel C. Peitsch 《Inflammation research》2015,64(7):471-486