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31.
CpG motifs have been advanced as agents that stimulate the maturation of DCs for immunotherapy. The present study tested the hypothesis that multiple doses of CpG-matured DC vaccine would be efficacious for complete eradication of experimentally-induced tumor. Accordingly, WEHI164 cells were implanted subcutaneously in the flank of BALB/c mice. During DC culture, tumor lysate was added to immature DCs followed by addition of CpG or non-CpG control 4–6 h later. A total of three doses of CpG or non-CpG control-matured DCs were injected around tumors. The results showed that multiple doses of CpG-matured DCs led to considerable decrease in cytotoxicity of lymphocytes and significantly increased tumor growth rate compared to a single dose. Further, mice which received three doses of the vaccine also displayed significant FoxP3 in tumor tissue. In conclusion, multiple doses of CpG-matured DCs exhibited decreased anti-tumor immunity in association with increased expression of FoxP3.  相似文献   
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HSPs (heat shock proteins) have been recognized to maintain cellular homoeostasis during changes in microenvironment. The present study aimed to investigate the HSPs expression pattern in hierarchical neural differentiation stages from mouse embryonal carcinoma stem cells (P19) and its role in heat stressed exposed cells. For induction of HSPs, cells were heated at 42°C for 30 min and recovered at 37°C in different time points. For neural differentiation, EBs (embryoid bodies) were formed by plating P19 cells in bacterial dishes in the presence of 1 mM RA (retinoic acid) and 5% FBS (fetal bovine serum). Then, on the sixth day, EBs were trypsinized and plated in differentiation medium containing neurobasal medium, B27, N2 and 5% FBS and for an extra 4 days. The expression of HSPs and neural cell markers were evaluated by Western blot, flow cytometry and immunocytochemistry in different stages. Our results indicate that HSC (heat shock constant)70 and HSP60 expressions decreased following RA treatment, EB formation and in mature neural cells derived from heat-stressed single cells and not heat-treated EBs. While the level of HSP90 increased six times following maturation process, HSP25 was expressed constantly during neural differentiation; however, its level was enhanced with heat stress. Accordingly, heat shock 12 h before the initiation of differentiation did not affect the expression of neuroectodermal and neural markers, nestin and β-tubulin III, respectively. However, both markers increased when heat shock was induced after treatment and when EBs were formed. In conclusion, our results raise the possibility that HSPs could regulate cell differentiation and proliferation under both physiological and pathological conditions.  相似文献   
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The Ovarian cancer G protein-coupled Receptor 1 (OGR1; GPR68) is proton-sensitive in the pH range of 6.8 - 7.8. However, its physiological function is not defined to date. OGR1 signals via inositol trisphosphate and intracellular calcium, albeit downstream events are unclear. To elucidate OGR1 function further, we transfected HEK293 cells with active OGR1 receptor or a mutant lacking 5 histidine residues (H5Phe-OGR1). An acute switch of extracellular pH from 8 to 7.1 (10 nmol/l vs 90 nmol/l protons) stimulated NHE and H(+)-ATPase activity in OGR1-transfected cells, but not in H5Phe-OGR1-transfected cells. ZnCl(2) and CuCl(2) that both inhibit OGR1 reduced the stimulatory effect. The activity was blocked by chelerythrine, whereas the ERK1/2 inhibitor PD 098059 had no inhibitory effect. OGR1 activation increased intracellular calcium in transfected HEK293 cells. We next isolated proximal tubules from kidneys of wild-type and OGR1-deficient mice and measured the effect of extracellular pH on NHE activity in vitro. Deletion of OGR1 affected the pH-dependent proton extrusion, however, in the opposite direction as expected from cell culture experiments. Upregulated expression of the pH-sensitive kinase Pyk2 in OGR1 KO mouse proximal tubule cells may compensate for the loss of OGR1. Thus, we present the first evidence that OGR1 modulates the activity of two major plasma membrane proton transport systems. OGR1 may be involved in the regulation of plasma membrane transport proteins and intra- and/or extracellular pH.  相似文献   
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Limber pine ( Pinus flexilis ) is a keystone species of high‐elevation forest ecosystems of western North America, but some parts of the geographic range have high infection and mortality from the non‐native white pine blister rust caused by Cronartium ribicola . Genetic maps can provide essential knowledge for understanding genetic disease resistance as well as local adaptation to changing climates. Exome‐seq was performed to construct high‐density genetic maps in two seed families. Composite maps positioned 9612 unigenes across 12 linkage groups ( LG s). Syntenic analysis of genome structure revealed that the majority of orthologs were positional orthologous genes ( POG s) with localization on homologous LG s among conifer species. Gene ontology ( GO) enrichment analysis showed relatively fewer constraints for POG s with putative roles in adaptation to environments and relatively more conservation for POG s with roles in basic cell function and maintenance. The mapped genes included 639 nucleotide‐binding site leucine‐rich repeat genes ( NBS LRR s) , 290 receptor‐like protein kinase genes ( RLK s), and 1014 genes with potential roles in the defense response and induced systemic resistance to attack by pathogens. Orthologous loci for resistance to rust pathogens were identified and were co‐positioned with multiple members of the R gene family, revealing the evolutionary pressure acting upon them. This high‐density genetic map provides a genomic resource and practical tool for breeding and genetic conservation programs, with applications in genome‐wide association studies ( GWASs ), the characterization of functional genes underlying complex traits, and the sequencing and assembly of the full‐length genomes of limber pine and related Pinus species.  相似文献   
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Environmental contamination by petroleum hydrocarbons, mainly crude oil waste from refineries, is becoming prevalent worldwide. This study investigates the bioremediation of water contaminated with crude oil waste. Bacillus salamalaya 139SI, a bacterium isolated from a private farm soil in the Kuala Selangor in Malaysia, was found to be a potential degrader of crude oil waste. When a microbial population of 108 CFU ml-1 was used, the 139SI strain degraded 79% and 88% of the total petroleum hydrocarbons after 42 days of incubation in mineral salt media containing 2% and 1% of crude oil waste, respectively, under optimum conditions. In the uninoculated medium containing 1% crude oil waste, 6% was degraded. Relative to the control, the degradation was significantly greater when a bacteria count of 99 × 108 CFU ml-1 was added to the treatments polluted with 1% oil. Thus, this isolated strain is useful for enhancing the biotreatment of oil in wastewater.  相似文献   
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Objective: The objective was to assess the predictive value of weight‐for‐age to identify overweight children and adolescents in the unusual research or public health situations where height is not available to calculate BMI. Research Methods and Procedures: Data from the National Health and Nutrition Examination Survey 1999 to 2004 were used to calculate the sensitivity, specificity, and positive and negative predictive values of selected weight‐for‐age cut‐off points to identify overweight children and adolescents (as defined by BMI ≥95th percentile). Positive and negative predictive values are dependent on prevalence and are reported here for this study population only. Results: The 50th and 75th weight‐for‐age percentiles had good sensitivity (100% and 99.6%, respectively), but poor positive predictive value (23.7% and 37.0%, respectively), while the 95th and 97th percentiles had reasonable positive predictive value (80.3% and 91.5%, respectively), but limited sensitivity (82.0% and 66.7%, respectively) to identify overweight subjects. The properties of weight‐for‐age percentiles to identify overweight subjects differed between sex, age, and race/ethnicity but remain within a relatively narrow range. Discussion: No single weight‐for‐age cut‐off point was found to identify overweight children and adolescents with acceptable values for all properties and, therefore, cannot be used in the clinical setting. Furthermore, the positive predictive values reported here may be lower in populations with a lower prevalence of obesity. However, in unusual research or public health situations where height is not available, such as existing databases, weight‐for‐age percentiles may be useful to target limited resources to groups more likely to include overweight children and adolescents than the general population.  相似文献   
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Diffusion and movement of subcutaneously injected biologics and high-concentration immunoglobulin G (IgG) therapeutics away from the injection site and through the subcutaneous (SC) tissue may be concentration dependent. This possibility was confirmed by in situ measurement of diffusion coefficients of unlabeled bovine IgG in phosphate-buffered saline within an in vitro hyaluronic acid matrix that represents the SC electrostatic environment. Diffusion decreased from 2.67 to 0.05 × 10−7 cm2/s when IgG concentration increased from 25 to 73 mg/mL. The results demonstrated that in situ detection of unlabeled proteins within an in vitro SC environment provides another useful tool for the preclinical characterization of injectable biologics.  相似文献   
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BackgroundThe present research was aimed to compare the toxicity and effectiveness of conventional fractionated radiotherapy versus hypo-fractionated radiotherapy in breast cancer utilizing a radiobiological model.Materials and methodsThirty-five left-sided breast cancer patients without involvement of the supraclavicular and axillary lymph nodes (with the nodal stage of N0) that had been treated with conventional or hypo-fractionated were incorporated in this study. A radiobiological model was performed to foretell normal tissue complication probability (NTCP) and tumor control probability (TCP).ResultsThe data represented that TCP values for conventional and hypo-fractionated regimens were 99.16 ± 0.09 and 95.96 ± 0.48, respectively (p = 0.00). Moreover, the NTCP values of the lung for conventional and hypo-fractionated treatment were 0.024 versus 0.13 (p = 0.035), respectively. Also, NTCP values of the heart were equal to zero for both regimens.ConclusionIn summary, hypo-fractionated regimens had comparable efficacy to conventional fraction radiation therapy in the case of dosimetry parameters for patients who had left breast cancer. But, utilizing the radiobiological model, conventional fractionated regimens presented better results compared to hypo-fractionated regimens.  相似文献   
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