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21.
Kowalska A Brunner B Bozsaky E Chen QR Stock C Lörch T Khan J Ambros PF 《Cytogenetic and genome research》2008,121(1):1-6
We aimed to directly align a chromosomal CGH (cCGH) pattern with the gene mapping data by taking advantage of the clustering of the GGCC motif at certain positions in the human genome. The alignment of chromosomal with sequence data was achieved by superimposition of (i) the fluorescence intensity of the sequence specific fluorochrome, Chromomycin A3 (CMA3), (ii) the cCGH fluorescence intensity profile of individual chromosomes and (iii) the GGCC density profile extracted from the Ensembl genome sequence database. The superimposition of these three pieces of information allowed us to precisely localize regions of amplification in the neuroblastoma cell line STA-NB-15. Two prominent cCGH peaks were noted, one at 2p24.3, the position 15.4 mega base (Mb), and the other at 2p23.2, 29.51 Mb. FISH and high resolution array CGH (aCGH) experiments disclosed an amplification of MYCN (16 Mb) and ALK (29.2-29.9 Mb), thus confirming the cCGH data. The combined visualization of sequence information and cCGH data drastically improves the resolution of the method to less than 2 Mb. 相似文献
22.
Eveline C van Asbeck Andy IM Hoepelman Jelle Scharringa Bjorn L Herpers Jan Verhoef 《BMC microbiology》2008,8(1):229
Background
Mannose binding lectin (MBL) is an important host defence protein against opportunistic fungal pathogens. This carbohydrate-binding protein, an opsonin and lectin pathway activator, binds through multiple lectin domains to the repeating sugar arrays displayed on the surface of a wide range of clinically relevant microbial species. We investigated the contribution of MBL to antifungal innate immunity towards C. parapsilosis in vitro. 相似文献23.
Katrien Swerts Peter F Ambros Chantal Brouzes José M Fernandez Navarro Nicole Gross Dyanne Rampling Roswitha Schumacher-Kuckelkorn Angela R Sementa Ruth Ladenstein Klaus Beiske 《The journal of histochemistry and cytochemistry》2005,53(12):1433-1440
Standard cytomorphological examination of bone marrow (BM) aspirates does not appear to be sensitive enough to detect single neuroblastoma cells. The SIOPEN Neuroblastoma Bone Marrow Committee developed a sensitive and reproducible anti-GD2 immunocytochemical assay and introduced morphological and immunocytological criteria for the interpretation of results. Fixed cytospins were incubated with a commercially available anti-GD2 monoclonal antibody and an APAAP kit. Cells fulfilling all morphological and immunocytological criteria were called criteria-positive cells (CPCs). Not convincingly interpretable cells fulfilled some, but not all, criteria, and negative cells displayed only exclusion criteria. The genetic profile of doubtful cells was checked by fluorescence in situ hybridization. Ideally, 3 x 10(6) cells were analyzed to reach a 95% probability of detecting one tumor cell in 1 x 10(6) mononuclear cells. Four quality control rounds were organized to validate the method. A total of 111 quality control samples were analyzed. Two main improvements were achieved: in discordant cases, the range between the lowest and highest reported result was reduced by half, and discordant results were only found in samples with less than 10 CPCs per 1 x 10(6). This article describes the first internationally standardized protocol to detect and quantify rare neuroblastoma cells by immunocytochemistry. This method is an indispensable tool for multicenter studies evaluating the clinical significance of minimal residual disease in neuroblastoma. 相似文献
24.
The idea of immunological surveillance against cancer has existed for nearly 100 years but as no conclusive evidence has yet
been published the importance of the cellular immune defense in the detection and removal of incipient or existing tumors
is still a hotly debated subject. However, in order to select a relevant immunotherapeutic strategy in the treatment of cancer,
a fundamental understanding of the basic immunologic conditions under which a tumor develops and exists is a prerequisite.
Therefore, a murine model was set up that we hoped would enable us to confirm or reject the theory of immunological surveillance.
A large panel of methylcholanthrene induced tumors was established in T-cell immunodeficient nude mice and congenic normal
mice to study the influence of the immune system on developing tumors. As nude mice developed tumors fastest and with the
highest incidence, we concluded that in this model the immune system constituted a ‘tumor-suppressive factor’ delaying and
sometimes abrogating tumor growth, i.e. performing immune surveillance. Immunogenicity of the tumors was assessed by transplantation
back to normal histocompatible mice. Tumors originating from the immunodeficient nude mice turned out to be far more immunogenic
than tumors from normal mice, resulting in a high rejection rate. CD8+cytotoxic T cells were found to be indispensable for
this rejection, leading to the conclusion that the cytotoxic T cells perform immune selection in normal mice, eliminating
immunogenic tumor cell variants in the incipient tumor.
In this review, we discuss the difficulties facing immunotherapy when conclusions are drawn from the presented observations
and hypotheses. 相似文献
25.
Early evolution of metazoan serine/threonine and tyrosine kinases: identification of selected kinases in marine sponges 总被引:14,自引:1,他引:13
The phylum Porifera (sponges) was the first to diverge from the common
ancestor of the Metazoa. In this study, six cDNAs coding for protein-
serine/threonine kinases (PS/TKs) are presented; they have been isolated
from libraries obtained from the demosponges Geodia cydonium and Suberites
domuncula and from the calcareous sponge Sycon raphanus. Sequence
alignments of the catalytic domains revealed that two major families of
PS/TK, the "conventional" (Ca(2+)-dependent) protein kinase C (PKC), the
cPKC subfamily, as well as the "novel" (Ca(2+)- independent) PKC (nPKC),
form two separate clusters. In each cluster, the sequence from S. raphanus
diverges first. To approach the question about the origin of
protein-tyrosine kinases (PTK), which are found only in Metazoa, we
analyzed two additional PS/TKs which have been cloned from S. domuncula:
the stress-responsive protein kinase (KRSvSD) and the
protein-kinase-C-related kinase (PRKvSD). The construction of the
phylogenetic tree, comprising the eight PS/TKs and the PTK cloned
previously from G. cydonium, revealed that the PTK derived from the branch
including the KRSvSD kinase. These data facilitate the first molecular
approach to elucidate the origin of metazoan PTK within the PS/TK
superfamily.
相似文献
26.
Localization of Agrobacterium rhizogenes T-DNA in plant chromosomes by in situ hybridization 总被引:7,自引:2,他引:5 下载免费PDF全文
We have used in situ hybridization to determine the sites of insertion of Agrobacterium rhizogenes Ri T-DNA in the chromosomes of Crepis capillaris (2n = 6) transformed roots. Four transformed root lines were obtained by infecting Crepis stem segments with A. rhizogenes. Southern hybridization analysis indicated that each root line was the result of one or more independent T-DNA insertion events. In two root lines, one copy of T-DNA was present; the other two root lines each contained two copies of T-DNA. To localize these T-DNA inserts on Crepis chromosomes, metaphase spreads were perpared from each root line, and hybridized in situ to a biotinlabeled T-DNA probe. The results indicated that T-DNA was present in a different chromosomal location in each root line, and that each chromosome had been a target for T-DNA insertion at least once. In the root lines containing two T-DNA inserts, two patterns of integration were observed: in one case the T-DNAs were present on separate chromosomes; in the other case the two T-DNAs were close together (but not tandemly arranged) on a single chromosome. A comparison of these results and those obtained previously for a fifth Crepis-transformed root line demostrated that Ri T-DNA does not insert preferentially into a particlar chromosomal location. 相似文献
27.
Correlation of pachytene chromomeres and metaphase bands of human chromosomes, and distinctive properties of telomeric regions 总被引:7,自引:0,他引:7
By means of double staining with DAPI and chromomycin A3, we show that the chromomeres of human pachytene chromosomes are generally DAPI positive and chromomycin negative, like the G- or Q-bands of mitotic chromosomes. Thus we have demonstrated, using an objective technique not based on morphological comparisons, that chromomeres and G-bands are equivalent. However, terminal chromomeres and the ends of mitotic chromosomes, as well as a few other sites, are chromomycin positive and DAPI negative. The ends of human chromosomes appear, therefore, to contain a distinctive class of GC-rich DNA. 相似文献
28.
Jae Chul SHIM Dong-Kyu LEE Terry A. KLEIN Heung-Chul KIM Won-Ja LEE Heung Ku IM 《Entomological Research》2010,40(4):202-210
After re-emergence of malaria in 1993, a continued increase in Plasmodium vivax cases was observed from 1993 to 2006 in northern Gyeonggi and Gangwon Provinces adjacent to the demilitarized zone separating North from South Korea. Annual parasite incidence per 1000 people ranged from 0.33 in 2004 to 0.89 in 2006. While malaria case rates declined (22.6%) in 2004, they increased 75.1% in 2005 and 51.7% in 2006 from the previous years. An initial incorrect diagnosis of 46.8% of malaria cases as common cold resulted in a mean delay of 1.3 days for the detection malarial parasites. Of the total cases, 10.2% from December to May were due to latent intrinsic incubation infections acquired the previous malaria season and the rest of the cases from June to November were either latent or short incubation infections. Overall, the peak anopheline population occurred from July to September, resulting in a similar peak in malaria cases. While malaria cases increased during 2005–2006, anopheline populations, based on trap indices, were not significantly different during 4 years of surveillance. To decrease the malaria patient infective period to mosquitoes, public health centers in Paju and Cheorwon in 2006 prescribed chloroquine + primaquine at days 0–3 after initial malaria diagnosis followed by an additional 11 days of primaquine (early primaquine treatment), rather than chloroquine on days 0–3 and primaquine on days 4–17 (delayed primaquine treatment). A reduction in the malaria parasite incidence during 2007 was recorded for the two locations offering the early primaquine treatment relative to other locations using the delayed primaquine treatment. 相似文献
29.
Background
The analysis of microarray experiments requires accurate and up-to-date functional annotation of the microarray reporters to optimize the interpretation of the biological processes involved. Pathway visualization tools are used to connect gene expression data with existing biological pathways by using specific database identifiers that link reporters with elements in the pathways. 相似文献30.
Ambros V 《Development (Cambridge, England)》1999,126(9):1947-1956
In Caenorhabditis elegans, the fates of the six multipotent vulva precursor cells (VPCs) are specified by extracellular signals. One VPC expresses the primary (1 degrees ) fate in response to a Ras-mediated inductive signal from the gonad. The two VPCs flanking the 1 degrees cell each express secondary (2 degrees ) fates in response to lin-12-mediated lateral signaling. The remaining three VPCs each adopt the non-vulval tertiary (3 degrees ) fate. Here I describe experiments examining how the selection of these vulval fates is affected by cell cycle arrest and cell cycle-restricted lin-12 activity. The results suggest that lin-12 participates in two developmental decisions separable by cell cycle phase: lin-12 must act prior to the end of VPC S phase to influence a 1 degrees versus 2 degrees cell fate choice, but must act after VPC S phase to influence a 3 degrees versus 2 degrees cell fate choice. Coupling developmental decisions to cell cycle transitions may provide a mechanism for prioritizing or ordering choices of cell fates for multipotential cells. 相似文献