排序方式: 共有97条查询结果,搜索用时 62 毫秒
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Victoria Cavaliere Daniela L Papademetrio Mario Lorenzetti Pamela Valva María Victoria Preciado Patricia Gargallo Irene Larripa Mariela B Monreal María Laura Pardo Silvia E Hajos Guillermo AC Blanco élida MC álvarez 《Translational oncology》2009,2(1):46-58
Chemotherapy aims to limit proliferation and induce apoptotic cell death in tumor cells. Owing to blockade of signaling pathways involved in cell survival and proliferation, nuclear factor κB (NF-κB) inhibitors can induce apoptosis in a number of hematological malignancies. The efficacy of conventional chemotherapeutic drugs, such as vincristine (VCR) and doxorubicine (DOX), may be enhanced with combined therapy based on NF-κB modulation. In this study, we evaluated the effect of caffeic acid phenylethyl ester (CAPE) and MG-132, two nonspecific NF-κB inhibitors, and conventional chemotherapeutics drugs DOX and VCR on cell proliferation and apoptosis induction on a lymphoblastoid B-cell line, PL104, established and characterized in our laboratory. CAPE and MG-132 treatment showed a strong antiproliferative effect accompanied by clear cell cycle deregulation and apoptosis induction. Doxorubicine and VCR showed antiproliferative effects similar to those of CAPE and MG-132, although the latter drugs showed an apoptotic rate two-fold higher than DOX and VCR. None of the four compounds showed cytotoxic effect on peripheral mononuclear cells from healthy volunteers. CAPE- and MG-132-treated bone marrow cells from patients with myeloid and lymphoid leukemias showed 69% (P < .001) and 25% decrease (P < .01) in cell proliferation and 42% and 34% (P < .01) apoptosis induction, respectively. Overall, our results indicate that CAPE and MG-132 had a strong and selective apoptotic effect on tumor cells that may be useful in future treatment of hematological neoplasias. 相似文献
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Analysis of the herpes simplex virus genome during in vitro latency in human diploid fibroblasts and rat sensory neurons. 总被引:11,自引:6,他引:5 下载免费PDF全文
We have previously designed in vitro model systems to characterize the herpes simplex virus type 1 (HSV-1) genome during in vitro virus latency. Latency was established by treatment of infected human embryo lung fibroblast (HEL-F) cells or rat fetal neurons with (E)-5-(2-bromovinyl)-2'-deoxyuridine and human leukocyte interferon and was maintained by increasing the incubation temperature after inhibitor removal. Virus was reactivated by reducing the incubation temperature. We have now examined the HSV-1-specific DNA content of latently infected HEL-F cells and rat fetal neurons treated with (E)-5-(2-bromovinyl)-2'-deoxyuridine and human leukocyte interferon and increased temperature. The HEL-F cell population contained, on an average, between 0.25 and 0.5 copies of most, if not all, HSV-1 HindIII and XbaI DNA fragments per haploid cell genome equivalent. In contrast, the latently infected neurons contained, on an average, 8 to 10 copies per haploid cell genome equivalent of most HSV-1 BamHI DNA fragments. There was no detectable alteration in size or molarity of the HSV-1 terminal or junction DNA fragments obtained by HindIII, XbaI, or BamHI digestion of the latently infected neuron or HEL-F cell DNA, as compared with digestion of a reconstruction mixture of purified HSV-1 virion and HEL-F cell DNAs. These data suggest that the predominant form of the HSV-1 genome in either latently infected cell population is nonintegrated, linear, and nonconcatameric. 相似文献
84.
Patterns of ribosomal RNA evolution in salamanders 总被引:4,自引:0,他引:4
Sequence comparisons are presented for four segments of the large subunit
of ribosomal RNA, including divergent domains D7a and D7b, portions of the
large divergent domains D2, D3, and D8, and evolutionarily conservative
sequences flanking divergent domains. These results resolve phylogenetic
relationships among exemplars of seven families of salamanders and the
three amphibian orders. Phylogenetic analysis confirms the prediction that
divergent domains feature the highest relative rates of base substitution
and length variation within the ribosome, but the divergent domains evolve
more slowly than nuclear noncoding DNA and the silent sites of structural
genes. Base substitutions demonstrate approximately twice as many
transitions as transversions and an uneven distribution among sites within
the divergent domains but no apparent bias in base composition. Length
mutations are primarily small insertions and deletions, with deletions
predominating. The divergent domains appear to be a good source of
phylogenetic information for evolutionary events occurring approximately
100-200 million years ago.
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85.
Parasitism in captive and reintroduced red wolves 总被引:1,自引:0,他引:1
Fecal examinations revealed that at least 10 of 21 (48%) captive red wolves (Canis rufus) and eight of 12 (67%) free-ranging red wolves were infected with intestinal parasites. No captive wolves and only one of seven reintroduced wolves had dirofilariasis. Ticks were collected from 10 of 21 (48%) captive wolves and nine of 12 (75%) free-ranging animals. Ivermectin administered at a dosage of 50 micrograms/kg of estimated body weight every 30 to 60 days apparently prevented or ameliorated parasitism in red wolves. 相似文献
86.
Comparison of the effects of concentration, pH and anion species on astringency and sourness of organic acids 总被引:4,自引:1,他引:3
The separate effects of concentration, pH and anion species on intensity of
sourness and astringency of organic acids were evaluated. Judges rated
sourness and astringency intensity of lactic, malic, tartaric and citric
acid solutions at three levels of constant pH varying in normality and at
three levels of constant concentration varying in pH. To assess the
comparative sourness and astringency of the organic acid anions of study,
binary acid solutions matched in pH and titratable acidity were also rated.
As pH was decreased in equinormal solutions, both sourness and astringency
increased significantly (P < 0.001). By contrast, as the normality of
the equi-pH solutions was increased, only sourness demonstrated significant
increases (P < 0.001) while astringency remained constant or decreased
slightly. At the lowest normality tested, all solutions were more
astringent than sour (P < 0.05). Although lactic acid was found to be
significantly more sour than citric acid (P < 0.05), no other sourness
or astringency differences among the organic acid anions were noted. This
study demonstrates for the first time that astringency elicited by acids is
a function of pH and not concentration or anion species, and confirms that
sourness is independently influenced by concentration, pH and anion species
of the acid.
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Willeke MC van Roon-Mom Barry A Pepers Peter AC 't Hoen Carola ACM Verwijmeren Johan T den Dunnen Josephine C Dorsman GertJan B van Ommen 《BMC molecular biology》2008,9(1):84
Background
Huntington's disease is a progressive autosomal dominant neurodegenerative disorder that is caused by a CAG repeat expansion in the HD or Huntington's disease gene. Although micro array studies on patient and animal tissue provide valuable information, the primary effect of mutant huntingtin will inevitably be masked by secondary processes in advanced stages of the disease. Thus, cell models are instrumental to study early, direct effects of mutant huntingtin. mRNA changes were studied in an inducible PC12 model of Huntington's disease, before and after aggregates became visible, to identify groups of genes that could play a role in the early pathology of Huntington's disease. 相似文献90.
The sugar binding activity of MR60, a mannose-specific shuttling lectin, requires a dimeric state 总被引:1,自引:0,他引:1
MR60 is an intracellular membrane protein which has been shown to act as a
mannoside specific lectin and to be identical to ERGIC-53, a protein
characteristic of the endoplasmic reticulum-Golgi apparatus- intermediate
compartment, acting as a shuttle. According to its primary sequence, this
MR60/ERGIC-53 protein contains a luminal domain including the carbohydrate
recognition domain, a stem, a transmembrane segment and a cytosolic domain.
The endogenous MR60/ERGIC-53 protein is spontaneously oligomeric, (dimers
and hexamers). In this paper, we study the relationship between the
oligomerization state and the sugar binding capacity by using recombinant
proteins. The expression of the recombinant proteins was evidenced by
immunocytochemistry and by immunoprecipitation followed by SDS-PAGE
analysis. The full size recombinant protein binds mannosides and is
oligomeric, up to the hexameric form. Two truncated proteins lacking the
transmembrane and the cytosolic domains were prepared and characterized. A
long one, containing the cysteine 466 close to the C-terminal end of the
recombinant protein but lacking the cysteine 475, close to the C- terminal
end of the native protein, does bind mannosides and forms dimers but no
higher oligomeric forms. A shorter one, lacking both the cysteines 466 and
475, does not bind mannosides and does not form dimers or higher polymers.
The two cysteines in the carbohydrate recognition domain (C190 and C230)
are not involved in the stabilization of oligomers. In conclusion, this
study shows that the luminal moiety of MR60/ERGIC-53 contains a device
allowing both its oligomeric pattern and its sugar binding capability.
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