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91.
Mohamed Ismail Richard Morgan Kevin Harrington John Davies Hardev Pandha 《Cryobiology》2010,61(3):268-274
Tumour cryotherapy has been described as both immunostimulatory and immunoinhibitory in previous studies. However, previous studies have not accurately reproduced the precise conditions of current clinical cryotherapy. The objective of this study is to assess the immunological effects of cryotreated whole tumour cells on dendritic cells (DC) maturation and function using an in vitro model. Prostate cancer cells were cooled using Endocare cryo-system to mimic temperatures achieved during clinical cryotherapy. Human DC were prepared from cluster of differentiation (CD) 14 monocytes and matured with lipopolysaccharide (LPS). Cryotreated cancer cells were added to DC on day 3. On day 7, DC were harvested and phenotyped. Cytokine gene expression was assessed using real time quantitative polymerase chain reaction (RT-PCR). Functional activity of DC was assessed in allogenic mixed lymphocyte reaction (MLR) and the molecular changes using gene microarray technology. There was statistically significant upregulation of costimulatory molecules and maturation markers (CD86, CD83, CD80 and CL II) in DC loaded with cryotreated whole tumour cells compared to both control DC and DC matured with LPS (P < 0.001). There was a significant increase in stimulatory cytokines gene expression (IL-2, IL-12, IL-15, IL-18 and IFN-γ). However, IL-10 and TGF-β expression reduced significantly. The effect of different freezing temperature was equal. cDNA microarray analysis showed upregulation of interleukin 1 (IL-1) and cycline dependent kinase inhibitor 1A (CDKN1A (p21) and downregulation of Caspase 8 and BCL2. Overall, our findings suggest that the effect of cryotherapy is generally stimulatory to DC which may enhance anti-tumour effects. Therefore, the combination of cryotherapy and DC vaccine may represent a novel method to increase the efficacy of cryotherapy especially at the peripheral zones of the prostate where cells are exposed to sub-lethal temperature. 相似文献
92.
93.
doi: 10.1111/j.1741‐2358.2011.00510.x Edentulism and dental caries in Victorian nursing homes Objectives: The aim of this project was to investigate edentulism and dental caries in nursing home residents in Victoria, Australia. Background: The Australian population is ageing with a growing number of people living in nursing homes. These residents are at increased risk for dental caries, have more teeth present now than at any time in the past 50 years and often have difficulty maintaining adequate oral hygiene. Materials and methods: Clinical dental examinations were conducted at 31 nursing homes in Melbourne and regional Victoria between May 2005 and June 2006. A total of 510 residents were examined out of 1345 eligible participants. Socio‐demographic and medical history was collected via questionnaire. Results: Just over half of the residents were dentate (53.9%), and dentate residents had a mean of 14.4 teeth present and 2.66 untreated decayed teeth. Residents who required total assistance with oral hygiene had more decayed teeth and fewer filled teeth than residents who did not require assistance. Conclusions: Nursing home residents in Victoria are retaining an increasing number of natural teeth and have more tooth surfaces at risk for dental caries. Untreated dental caries was a significant problem for residents, particularly for those who are dependent on others for their daily oral hygiene care. 相似文献
94.
Summary Several mammalian uterine and conceptus proteins are produced at specific stages of implantation. Ovine trophoblast protein-1 (OTP-1) is only synthesised of pregnancy (dpc). This immunogold ultracryosection study shows that, during this period, OTP-1 immunoreactivity is only found in the Golgi body of the trophectodermal cells. A second protein, of 14 kD molecular weight (14K protein), has a more varied distribution being found in membrane-bounded crystals in uterine epithelium and trophectodermal cells, and distributed throughout the cytosol and nucleoplasm of the uterine epithelium. There are only trace amounts of the 14 K protein in the fetomaternal syncytium which replaces the uterine epithelium during implantation, and no crystals are found in the trophectoderm after cotyledonary villus formation is initiated at 24–25 dpc. The crystals containing 14 K protein persist throughout pregnancy in the intercotyledonary areas. The narrow time window of OTP-1 occurrence reinforces the suggestion that this represents an important developmental signal, whereas the distribution of the 14 K protein indicates a more general nutritive function. 相似文献
95.
Görel Nyman Stina Marntell Anna Edner Pia Funkquist Karin Morgan Göran Hedenstierna 《Acta veterinaria Scandinavica》2009,51(1):22
Background
Sedation with α2-agonists in the horse is reported to be accompanied by impairment of arterial oxygenation. The present study was undertaken to investigate pulmonary gas exchange using the Multiple Inert Gas Elimination Technique (MIGET), during sedation with the α2-agonist detomidine alone and in combination with the opioid butorphanol. 相似文献96.
97.
Reversible cell damage by T-cell perforins. Calcium influx and propidium iodide uptake into K562 cells in the absence of lysis. 总被引:5,自引:0,他引:5 下载免费PDF全文
The non-lethal effects of the lymphocyte-derived pore-forming toxin perforin on the human erythroleukaemia cell line K562 were investigated. By using the fluorescent Ca2+ indicator fura-2, perforin was shown to cause intracellular Ca2+ concentration to rise transiently into the micromolar range in the absence of cell death. By fluorescence-activated cell sorting it was demonstrated that K562 cells took up the membrane-impermeant nuclear stain propidium iodide (PI) when exposed to non-lethal doses of perforin. The permeability to PI was short-lived, confirming the transience of the perforin pore. Analogies with non-lethal effects and recovery processes occurring in nucleated cells exposed to the membrane-attack complex of complement are drawn. 相似文献
98.
The structure, function, stability, and many other properties of a protein in a fixed environment are fully specified by its sequence, but in a manner that is difficult to discern. We present a general approach for rapidly mapping sequences directly to their energies on a pre-specified rigid backbone, an important sub-problem in computational protein design and in some methods for protein structure prediction. The cluster expansion (CE) method that we employ can, in principle, be extended to model any computable or measurable protein property directly as a function of sequence. Here we show how CE can be applied to the problem of computational protein design, and use it to derive excellent approximations of physical potentials. The approach provides several attractive advantages. First, following a one-time derivation of a CE expansion, the amount of time necessary to evaluate the energy of a sequence adopting a specified backbone conformation is reduced by a factor of 10(7) compared to standard full-atom methods for the same task. Second, the agreement between two full-atom methods that we tested and their CE sequence-based expressions is very high (root mean square deviation 1.1-4.7 kcal/mol, R2 = 0.7-1.0). Third, the functional form of the CE energy expression is such that individual terms of the expansion have clear physical interpretations. We derived expressions for the energies of three classic protein design targets-a coiled coil, a zinc finger, and a WW domain-as functions of sequence, and examined the most significant terms. Single-residue and residue-pair interactions are sufficient to accurately capture the energetics of the dimeric coiled coil, whereas higher-order contributions are important for the two more globular folds. For the task of designing novel zinc-finger sequences, a CE-derived energy function provides significantly better solutions than a standard design protocol, in comparable computation time. Given these advantages, CE is likely to find many uses in computational structural modeling. 相似文献
99.
Helicotylenchus oleae n. sp. and H. neopaxilli n. sp., from olive roots and soil in Italy, are described and illustrated. Helicotylenchus oleae can be distinguished from the related species H. canadensis and H. tunisiensis especially by the smaller styler, its distinctive tail shape, and a tail longer than one anal body width. Helicotylenchus neopaxilli differs from the close species H. paxilli by having a conical, anteriorly truncated labial region, shorter stylet, and phasmids always anterior to level of anus. Also illustrated and discussed are histopathological changes within feeder roots of olive caused by the feeding activity of the semi-endoparasitic H. oleae. 相似文献
100.