排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
2.
Guenterberg KD Lesinski GB Mundy-Bosse BL Karpa VI Jaime-Ramirez AC Wei L Carson WE 《Cancer immunology, immunotherapy : CII》2011,60(9):1281-1288
Interferon-alpha (IFN-α) is an immunomodulatory cytokine that is used clinically for the treatment of melanoma in the adjuvant
setting. The cellular actions of IFN-α are regulated by the suppressors of cytokine signaling (SOCS) family of proteins. We
hypothesized that the anti-tumor activity of exogenous IFN-α would be enhanced in SOCS1-deficient mice. SOCS1-deficient (SOCS1−/−) or control (SOCS1+/+) mice on an IFN-γ−/− C57BL/6 background bearing intraperitoneal (i.p.) JB/MS murine melanoma cells were treated for 30 days with i.p. injections
of IFN-A/D or PBS (vehicle). Log-rank Kaplan-Meier survival curves were used to evaluate survival. Tumor-bearing control SOCS1+/+ mice receiving IFN-A/D had significantly enhanced survival versus PBS–treated mice (P = 0.0048). The anti-tumor effects of IFN-A/D therapy were significantly enhanced in tumor-bearing SOCS1−/− mice; 75% of these mice survived tumor challenge, whereas PBS-treated SOCS1−/− mice all died at 13-16 days (P = 0.00038). Antibody (Ab) depletion of CD8+ T cells abrogated the anti-tumor effects of IFN-A/D in SOCS1−/− mice as compared with mice receiving a control antibody (P = 0.0021). CD4+ T-cell depletion from SOCS1−/− mice also inhibited the effects of IFN-A/D (P = 0.0003). IFN-A/D did not alter expression of CD80 or CD86 on splenocytes of SOCS1+/+ or SOCS1−/− mice, or the proportion of T regulatory cells or myeloid-derived suppressor cells in SOCS1+/+ or SOCS1−/− mice. An analysis of T-cell function did reveal increased proliferation of SOCS1-deficient splenocytes at baseline and in
response to mitogenic stimuli. These data suggest that modulation of SOCS1 function in T-cell subsets could enhance the anti-tumor
effects of IFN-α in the setting of melanoma. 相似文献
3.
Mitochondrial DNAs of six morphologically different Phytophthora species were digested with 15 restriction enzymes. The numbers of restriction fragments obtained differed considerably from those theoretically expected for random base distribution. Enzymes with relatively many G and C in their recognition sequences produced significantly larger numbers of fragments. Moreover, fragments generated by most of these enzymes were more often shared by two or more species than those from enzymes with more A and T in their recognition sequence. It is concluded that base distribution in mitochondrial DNA of Phytophthora is heterogeneous,AT-rich stretches occurring scattered over the mitochondrial genome and GC-rich regions present in conserved sequences, presumably genes. A practical consequence for taxonomic RFLP studies is that optimal enzymes can be selected, depending on the desired level of resolution. 相似文献
4.
The 18S ribosomal RNAs of 21 tetrapods were sequenced and aligned with five
published tetrapod sequences. When the coelacanth was used as an outgroup,
Lissamphibia (living amphibians) and Amniota (amniotes) were found to be
statistically significant monophyletic groups. Although little resolution
was obtained among the lissamphibian taxa, the amniote sequences support a
sister-group relationship between birds and mammals. Portions of the 28S
ribosomal RNA (rRNA) molecule in 11 tetrapods also were sequenced, although
the phylogenetic results were inconclusive. In contrast to previous
studies, deletion or down- weighting of base-paired sites were found to
have little effect on phylogenetic relationships. Molecular evidence for
amniote relationships is reviewed, showing that three genes
(beta-hemoglobin, myoglobin, and 18S rRNA) unambiguously support a
bird-mammal relationship, compared with one gene (histone H2B) that favors
a bird- crocodilian clade. Separate analyses of four other genes (alpha-
crystallin A, alpha-hemoglobin, insulin, and 28S rRNA) and a combined
analysis of all sequence data are inconclusive, in that different groups
are defined in different analyses and none are strongly supported. It is
suggested that until sequences become available from a broader array of
taxa, the molecular evidence is best evaluated at the level of individual
genes, with emphasis placed on those studies with the greatest number of
taxa and sites. When this is done, a bird-mammal relationship is most
strongly supported. When regarded in combination with the morphological
evidence for this association, it must be considered at least as plausible
as a bird-crocodilian relationship.
相似文献
5.
6.
7.
Moulinath Acharya Suddhasil Mookherjee Ashima Bhattacharjee Sanjay KD Thakur Arun K Bandyopadhyay Abhijit Sen Subhabrata Chakrabarti Kunal Ray 《BMC molecular biology》2007,8(1):21
Background
We investigated the molecular basis of primary open-angle glaucoma (POAG) using Opticin (OPTC) as a candidate gene on the basis of its expression in the trabecular meshwork cells involved in the disease pathogenesis. Two hundred POAG patients and 100 controls were enrolled in this study. The coding sequence of OPTC was amplified by PCR from genomic DNA of POAG patients, followed by SSCP, DHPLC and DNA sequencing. Subsequent bioinformatic analysis, site-directed mutagenesis, quantitative RT-PCR and western blot experiments were performed to address the functional significance of a 'silent' change in the OPTC coding region while screening for mutations in POAG patients. 相似文献8.
The effect of the administration of the mycotoxins OTA, ZEA and DON alone resp. in combination on animal health and the residue behavior of pigs from 50 – 60 kg living weight over 90 days was investigated in 4 separate studies. Due to its fast metabolisation the administration of 1000 µg DON resp. 250 µg ZEA per kg feed alone or in combination with other mycotoxins does not lead to detectable residues of these mycotoxins in organs and tissues. Therefore these mycotoxins should not be relevant to the consumer.There is an effect of the simultaneous administration of ZEA resp. DON on the metabolisation resp. secretion of OTA. OTA is of relevance from the point of view of residue toxicology. 相似文献
9.
An anchored restriction-mapping approach applied to the genetic analysis of the Anopheles gambiae malaria vector complex 1 总被引:1,自引:0,他引:1
We introduce here a simple approach for rapidly determining restriction
maps for a number of regions of a genome; this involves "anchoring" a map
with a rare restriction site (in this case the seldom-cutting EagI)
followed by partial digestion of a frequent-cutting enzyme (e.g., Sau 3A).
We applied this technology to five species of the Anopheles gambiae
complex. In a single Southern blot we obtained about a 15-kb restriction
map each for the mtDNA, rRNA gene, and a scnDNA region for each of five
species. Phylogenetic analyses of these regions yield trees at odds with
the more traditional chromosome inversion-based trees. The value of the
approach for systematic purposes is the ease with which several large,
independent regions of the genome can be quickly assayed for molecular
variation.
相似文献
10.
Abstract Nearly full-length, small subunit (SSU) rRNA was transcribed in vitro from clones of SSU rDNA genes. Comparing the use of in vitro-transcribed and native rRNA indicated that, when in vitro-transcribed rRNA was used as a standard for quantitative hybridizations with oligonucleotide probes, the population was consistently underestimated. The population abundance was expressed as a percentage of specific target SSU rRNA (determined with a specific oligonucleotide probe), relative to the total SSU rRNA (measured with a universal probe). Differences in hybridization signals could be related to specific probe target locations and rRNA denaturation conditions, suggesting that higher order structure is important in quantitative membrane hybridizations. Therefore, in vitro-transcribed rRNA cannot always be used for the absolute quantification of microbial populations, but can be employed as a standard to quantify shifts in population abundance over time, and to compare community structure in various environments. 相似文献