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51.
Vaccination with p53-peptide–pulsed dendritic cells,of patients with advanced breast cancer: report from a phase I study 总被引:3,自引:0,他引:3
Svane IM Pedersen AE Johnsen HE Nielsen D Kamby C Gaarsdal E Nikolajsen K Buus S Claesson MH 《Cancer immunology, immunotherapy : CII》2004,53(7):633-641
Peptides derived from over-expressed p53 protein are presented by class I MHC molecules and may act as tumour-associated epitopes. Due to the diversity of p53 mutations, immunogenic peptides representing wild-type sequences are preferable as a basis for a broad-spectrum p53-targeting cancer vaccine. Our preclinical studies have shown that wild-type p53-derived HLA-A2–binding peptides are able to activate human T cells and that the generated effector T cells are cytotoxic to human HLA-A2+, p53+ tumour cells. In this phase I pilot study, the toxicity and efficacy of autologous dendritic cells (DCs) loaded with a cocktail of three wild-type and three modified p53 peptides are being analysed in six HLA-A2+ patients with progressive advanced breast cancer. Vaccinations were well tolerated and no toxicity was observed. Disease stabilisation was seen in two of six patients, one patient had a transient regression of a single lymph node and one had a mixed response. ELISpot analyses showed that the p53-peptide–loaded DCs were able to induce specific T-cell responses against modified and unmodified p53 peptides in three patients, including two of the patients with a possible clinical benefit from the treatment. In conclusion, the strategy for p53-DC vaccination seems safe and without toxicity. Furthermore, indications of both immunologic and clinical effect were found in heavily pretreated patients with advanced breast cancer. An independent clinical effect of repeated administration of DCs and IL-2 can not of course be excluded; further studies are necessary to answer these questions. 相似文献
52.
Summary Modified B
S translocation males were developed at 26.0° C where univalentbearing gametes are recovered with less than half the frequency than at 18.0° C. Upon eclosion the males were stored for definite time periods at either temperature before mating individually to single y free-X females. the transfer cultures of the females show a higher frequency of recovery of univalent-bearing progeny regardless of the temperature or storage treatment of the male. In addition, postmeiotic temperature treatment does not appear to fundamentally alter the overall frequency of recovery of univalent-bearing gametes which is presumably determined by the developmental temperature of the male. A similar trend is observed for matings of y females to single X.YSYL/O males in which the males were developed and stored at 26.0° C; namely, a higher frequency of recovery of attached-XY gametes in the transfer cultures. 相似文献
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Helicobacter pylori infection and gastroesophageal reflux in a population-based study (The HUNT Study) 总被引:1,自引:0,他引:1
BACKGROUND AND AIM: It has been suggested that Helicobacter pylori infection may prevent gastroesophageal reflux, possibly through gastric atrophy. Since, however, previous results are contradictory and no population-based studies are available, the relationship between H. pylori and reflux remains uncertain. The aim of this study was to investigate this relationship in a population-based, nested, case-control study. METHODS: From a cohort of 65,363 individuals, representing 71.2% of the adult population in the Norwegian county of Nord-Trondelag, we randomly selected 472 persons with recurrent reflux symptoms (cases) and 472 without such symptoms (controls). Occurrence of H. pylori and its virulence factor cagA was determined serologically, using an immunoblot assay. Gastric atrophy was assessed through serum levels of pepsinogen I. Odds ratios (OR) with 95% confidence intervals (CI), adjusted for potential confounding factors, represented relative risks. RESULTS: H. pylori infection was not associated with a decreased risk of reflux symptoms (OR 1.1, 95% CI 0.8-1.6), irrespective of positive cagA status (OR 1.1, 95% CI 0.8-1.5). Gastric atrophy reduced the risk of reflux symptoms (OR 0.2, 95% CI 0.0-0.6). Infection with H. pylori entailed a ninefold increase in the risk of gastric atrophy compared to non-infection (OR 8.9, 95% CI 2.0-39.9). CONCLUSIONS: H. pylori infection, irrespective of cagA status, did not affect the occurrence of reflux symptoms in this population-based setting. Infected individuals are at increased risk of gastric atrophy, which in turn reduces reflux symptoms, but due to the low frequency of gastric atrophy among infected individuals overall, there was no association with reflux symptoms on a population level. 相似文献
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In winter 2000–2001, there was a serious outbreak of Gremmeniella abietina Morelet in southeastern Norway. During the outbreak, we noted that injured Scots pine trees (Pinus sylvestris L.) developed secondary buds in response to the fungus attack, and we decided to study the relationship between injury, appearance
of secondary buds and recovery of the trees thereafter. For this purpose, 143 trees from 10 to 50 years of age were chosen
and grouped into crown density classes. Injury was assessed in detail, and buds were counted before bud burst in the spring
of 2002. In addition, a subset of 15 trees was followed through the summer of 2002 to assess recovery. All injured trees developed
secondary buds, with a clear overweight of dormant winter buds in proportion to interfoliar buds. Healthy control trees did
not develop secondary buds at all. The secondary buds appeared predominantly on the injured parts of the tree; interfoliar
buds in particular developed just beneath the damaged tissue. Most of the secondary buds died during the winter of 2001–2002,
mainly because the fungus continued to spread after the first outbreak. Many of the remaining buds developed shoots with abnormal
growth during the summer. Secondary buds may help trees to recover from Gremmeniella attacks, but this strategy may fail when the fungus continues to grow and injure the newly formed buds and shoots. 相似文献
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Christine N. Bedore Stephen M. Kajiura S?nke Johnsen 《Proceedings. Biological sciences / The Royal Society》2015,282(1820)
Cephalopods, and in particular the cuttlefish Sepia officinalis, are common models for studies of camouflage and predator avoidance behaviour. Preventing detection by predators is especially important to this group of animals, most of which are soft-bodied, lack physical defences, and are subject to both visually and non-visually mediated detection. Here, we report a novel cryptic mechanism in S. officinalis in which bioelectric cues are reduced via a behavioural freeze response to a predator stimulus. The reduction of bioelectric fields created by the freeze-simulating stimulus resulted in a possible decrease in shark predation risk by reducing detectability. The freeze response may also facilitate other non-visual cryptic mechanisms to lower predation risk from a wide range of predator types. 相似文献
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