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51.
52.
We tested the principle of treating malignant ovarian tumors by vaccination against their ectopically expressed protein, zona pellucida glycoprotein (ZP) 3, using as the experimental model the granulosa cell tumors that develop in transgenic mice expressing the simian virus 40 T-antigen under the inhibin-α promoter (inhα/Tag). We found high ZP3 expression in granulosa cell tumors of the transgenic mice, in human surface ovarian cancer and granulosa cell lines, and in human granulosa cell tumors and their metastases. Early preventive immunization (between 2 and 5.5 mo of age) of transgenic mice with recombinant human (rh) ZP3 prevented ovarian tumorigenesis, and delayed therapeutic immunization (between 4.5 and 7 mo) reduced weights of existing tumors by 86 and 75%, respectively (P<0.001), compared to vehicle-treated control mice. No objective side effects of the immunizations were observed. Liver metastases were found in nontreated/vehicle-treated controls (n=7/39), but none following active rhZP3 immunizations (n=0/36; P<0.05). Immunization with rhZP3 was highly effective, as demonstrated by the induction of anti-ZP3 antibodies, as well as proliferative responses to the ZP3 antigen. These results signal rhZP3 immunization as a novel strategy to be developed for the immunotherapy of ovarian granulosa cell tumors, as well as for that of other malignancies that may express ZP3.  相似文献   
53.
Khan TA  Amani S  Naeem A 《Amino acids》2012,43(3):1311-1322
This study investigates the effect of pentose sugars (ribose and arabinose) on the structural and chemical modifications in glucose oxidase (GOD) as well as genotoxic potential of this modified form. An intermediate state of GOD was observed on day 12 of incubation having CD minima peaks at 222 and 208?nm, characteristic of α-helix and a few tertiary contacts with altered tryptophan environment and high ANS binding. All these features indicate the existence of molten globule state of the GOD with ribose and arabinose on day 12. GOD on day 15 of incubation forms β structures as revealed by CD and FTIR which may be due to its aggregation. Furthermore, GOD on day 15 showed a remarkable increase in Thioflavin T fluorescence at 485?nm. Comet assay of lymphocytes and plasmid nicking assay in presence of glycated GOD show DNA damage which confirmed the genotoxicity of advance glycated end products. Hence, our study suggests that glycated GOD results in the formation of aggregates and the advanced glycated end products, which are genotoxic in nature.  相似文献   
54.
Synthesis of flavones, 4-thioflavones and 4-iminoflavones was carried out with the substitution of variable halogens, methyl, methoxy and nitro groups in the A, B and AB rings of the respective compounds and we also report here their antibacterial activity. Most of the synthesized compounds were found to be active against Escherichia coli, Bacillus subtilis, Shigella flexnari, Salmonella aureus, Salmonella typhi and Pseudomonas aeruginosa. Activity of 4-thioflavones and 4-iminoflavones was found to be higher than that of their corresponding flavone analogues. Investigated compounds having substituents like F, OMe and NO2 at 4'-position in ring-B exhibited enhanced activity and the presence of electronegative groups in the studied compounds showed a direct relationship to the antibacterial activity.  相似文献   
55.
Soybean [Glycine max (L.) Merr.] cultivars varied in their resistance to different populations of the soybean cyst nematode (SCN), Heterodera glycines, called HG Types. The rhg1 locus on linkage group G was necessary for resistance to all HG types. However, the loci for resistance to H. glycines HG Type 1.3- (race 14) and HG Type 1.2.5- (race 2) of the soybean cyst nematode have varied in their reported locations. The aims were to compare the inheritance of resistance to three nematode HG Types in a population segregating for resistance to SCN and to identify the underlying quantitative trait loci (QTL). ‘Hartwig’, a soybean cultivar resistant to most SCN HG Types, was crossed with the susceptible cultivar ‘Flyer’. A total of 92 F5-derived recombinant inbred lines (RILs; or inbred lines) and 144 molecular markers were used for map development. The rhg1 associated QTL found in earlier studies were confirmed and shown to underlie resistance to all three HG Types in RILs (Satt309; HG Type 0, P = 0.0001 R 2 = 22%; Satt275; HG Type 1.3, P = 0.001, R 2 = 14%) and near isogeneic lines (NILs; or iso-lines; Satt309; HG Type 1.2.5-, P = 0.001 R 2 = 24%). A new QTL underlying resistance to HG Type 1.2.5- was detected on LG D2 (Satt574; P = 0.001, R 2 = 11%) among 14 RILs resistant to the other HG types. The locus was confirmed in a small NIL population consisting of 60 plants of ten genotypes (P = 0.04). This QTL (cqSCN-005) is located in an interval previously associated with resistance to both SDS leaf scorch from ‘Pyramid’ and ‘Ripley’ (cqSDS-001) and SCN HG Type 1.3- from Hartwig and Pyramid. The QTL detected will allow marker assisted selection for multigenic resistance to complex nematode populations in combination with sudden death syndrome resistance (SDS) and other agronomic traits.  相似文献   
56.
The significance of this study was to prepare various isoniazid derivatives by introducing the isoniazid core into several molecules to explore the possibilities of some altered biological activities. Series of 6-substituted-1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazole (3ag) and 1,3,4-oxadiazole (4ag and 5) derivatives of isoniazid were synthesized in satisfactory yield and pharmacologically evaluated for their anti-inflammatory, analgesic, ulcerogenic, and lipid peroxidation activities by known experimental models.  相似文献   
57.

Background

Glucocorticoid-mediated inhibition of angiogenesis is important in physiology, pathophysiology and therapy. However, the mechanisms through which glucocorticoids inhibit growth of new blood vessels have not been established. This study addresses the hypothesis that physiological levels of glucocorticoids inhibit angiogenesis by directly preventing tube formation by endothelial cells.

Methodology/Principal Findings

Cultured human umbilical vein (HUVEC) and aortic (HAoEC) endothelial cells were used to determine the influence of glucocorticoids on tube-like structure (TLS) formation, and on cellular proliferation (5-bromo-2′-deoxyuridine (BrdU) incorporation), viability (ATP production) and migration (Boyden chambers). Dexamethasone or cortisol (at physiological concentrations) inhibited both basal and prostaglandin F (PGF)-induced and vascular endothelial growth factor (VEGF) stimulated TLS formation in endothelial cells (ECs) cultured on Matrigel, effects which were blocked with the glucocorticoid receptor antagonist RU38486. Glucocorticoids had no effect on EC viability, migration or proliferation. Time-lapse imaging showed that cortisol blocked VEGF-stimulated cytoskeletal reorganisation and initialisation of tube formation. Real time PCR suggested that increased expression of thrombospodin-1 contributed to glucocorticoid-mediated inhibition of TLS formation.

Conclusions/Significance

We conclude that glucocorticoids interact directly with glucocorticoid receptors on vascular ECs to inhibit TLS formation. This action, which was conserved in ECs from two distinct vascular territories, was due to alterations in cell morphology rather than inhibition of EC viability, migration or proliferation and may be mediated in part by induction of thrombospodin-1. These findings provide important insights into the anti-angiogenic action of endogenous glucocorticoids in health and disease.  相似文献   
58.
Genetic instability in EBV-transformed lymphoblastoid cell lines   总被引:2,自引:0,他引:2  
Epstein Barr virus (EBV)-transformed lymphoblastoid cell lines are commonly used to provide an inexhaustible supply of DNA. We examined microsatellite instability in these cell lines in 35 individuals where DNA was available from the original blood samples and from cultured cell lines. Mutations were observed in 0.3% of the analyses, thus providing a quantitative measure of somatic mutation rate.  相似文献   
59.
Three new physalins (1-3) and a new withanolide 7 have been isolated from the whole plant of Physalis minima, along with three known physalins: physalin H (4), isophysalin B (5), and 5beta,6beta-epoxyphysalin B (6). Their structures were deduced on the basis of in-depth spectroscopic analyses. Compounds 1-6 showed significant in vitro leishmanicidal activities (0.92-19.4 microg/ml) against promastigotes of Leishmania major.  相似文献   
60.
Melanocortin receptors weigh in   总被引:2,自引:0,他引:2  
  相似文献   
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