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The effect of zinc deficiency on the direct-growth effect of growth hormone (GH) on tibia growth in hypophysectomized rats was studied. There were three dietary groups. Zinc deficient (ZD) group (0.9 mg/kg diet), control (C) group (66 mg/kg diet) and zinc adequate pair fed (PF) group (66 mg zinc/kg diet). All rats in each group received local infusion of recombinant human-growth hormone (hGH) (1 Μg/d), except for half of the animals in the control group, which were sham-treated, receiving vehicle infusion only. The substances were infused continuously for 13 d by osmotic minipumps through a catheter implanted into the right femoral artery. Food intake was lower and body weight loss was greater in ZD, and PF animals compared with C animals (p < 0.001). Tissuezinc concentration and plasma alkaline-phosphatase activity were decreased (p < 0.05) by dietary-zinc deficiency. GH infusion increased the tibial-epiphyseal width of the treated right limb, but not of the noninfused left limb in C and PF animals. However, in ZD rats, no difference was found between the infused and the noninfused limbs. These results demonstrate that zinc deficiency inhibits the direct-growth effect of GH on long-bone growth.  相似文献   
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Previously, a PR-10 protein Pin m III was described in western white pine. In this study, primers based on cDNA of Pin m III were utilized to obtain the genomic sequence of a Pin m III homologue – Pse m I – in Douglas-fir. A comparative analysis of a deduced amino acid sequence of Pin m III and Pse m I genes indicated about 80% similarity between the two protein sequences, and a consensus 20 amino acid sequence located around the p-loop sequence was used to synthesize a peptide of 20 amino acids. An antibody to this synthetic peptide was able to detect the Pse m I protein in Douglas-fir. The anti- Pse m I antibody was used in a western immunoblot to monitor seasonal variation of the Pse m I in Douglas-fir needles and its level was shown to increase with overwintering of Douglas-fir seedlings. However, unlike the Pin m III, there is no indication that the Pse m I is associated with frost hardiness. Analysis of infected Douglas-fir roots showed a possible trend to up-regulation of Pse m I by pathogens such as the laminated root rot fungus, Phellinus weirii . The expression of Pse m I protein in Douglas-fir seedlings is very low compared to the expression of Pin m III protein in western white pine seedlings. In addition, a light-harvesting complex I protein, PSI-F, was identified in Douglas-fir by N-terminal amino acid sequencing.  相似文献   
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Journal of Applied Phycology - Light is one of the most critical factors for the growth of microalgae; therefore, optimization and accessibility of light improve productivity and wastewater...  相似文献   
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Pinus monticola antimicrobial peptide 1 (Pm-AMP1) was expressed and purified from bacterial cell lysate and its identity and purity confirmed by Western blot analysis using the Pm-AMP1 antibody. Application of Pm-AMP1 resulted in visible hyphal growth inhibition of Cronartium ribicola , Phellinus sulphurascens , Ophiostoma montium , and Ophiostoma clavigerum 3-12 days post-treatment. Pm-AMP1 also inhibited spore germination of several other phytopathogenic fungi by 32%-84% 5?days post-treatment. Microscopic examination of C. ribicola hyphae in contact with Pm-AMP1 showed distinct morphological changes. Seven western white pine ( Pinus monticola Douglas ex D. Don) families (Nos. 1, 2, 5, 6, 7, 8, 10) showing partial resistance to C.?ribicola in the form of bark reaction (BR) were assessed by Western immunoblot for associations between Pm-AMP1 accumulation and family, phenotype, canker number, and virulence of C. ribicola. There was a significant difference (p?< 0.001) in mean Pm-AMP1 protein accumulation between families, with higher levels detected in the full-sib BR families (Nos. 1, 2, 5) than the half-sib BR families (Nos. 6, 7). Family 8, previously described as a Mechanism 'X' BR family, had the highest number of BR seedlings and displayed high Pm-AMP1 levels, whereas the susceptible family (No. 10) showed the lowest levels (p?< 0.05). Family 1 showed a significant association between Pm-AMP1 accumulation and overall seedling health (p?< 0.01, R?= 0.533), with higher protein levels observed in healthy versus severely infected seedlings. In general, low Pm-AMP1 levels were observed with an increase in the number of cankers per seedling (p?< 0.05), and seedlings inoculated with the avirulent source of C. ribicola showed significantly higher Pm-AMP1 levels (p?< 0.05) in the majority of BR families. Cis-acting regulatory elements, such as CCAAT binding factors, and an AG-motif binding protein were identified in the Pm-AMP1 promoter region. Multiple polymorphic sites were identified within the 5' untranslated region and promoter regions. Our results suggest that Pm-AMP1 is involved in the western white pine defense response to fungal infection, as observed by its antifungal activity on C. ribicola and a range of phytopathogens as well as through its association with different indicators of resistance to C.?ribicola.  相似文献   
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Activation of the PI3K/Akt pathway, a critical step for survival in cancer cells is often associated with decreased sensitivity to several chemotherapeutic drugs. PIK3CA gene amplification is observed in 16–24% of epithelial ovarian cancer (EOC) patients in conjunction with p53 mutations. A 900 bp long PIK3CA promoter is shown to be negatively regulated by p53 in ovarian surface epithelial cells but the consequence of chemotherapeutic drug treatments on this promoter in ovarian cancer cells is largely unknown. We aim to study the modulation of this promoter by cisplatin using an improved fusion reporter in ovarian cancer cells and tumor xenografts by non-invasive imaging approach. A PIK3CA sensor was developed using a bi-fusion reporter from a newly constructed library of bi- and tri-fusion vectors comprising of two mutant far red fluorescent proteins (mcherry/mch and tdTomato/tdt), a mutant firefly luciferase (fluc2), and a PET reporter protein (ttk). In vivo imaging of mice implanted with 293T cells transiently expressing these bi- and tri-fusion reporters along with respective controls revealed comparable activity of each reporter in the fusion background and fluc2-tdt as the most sensitive one. Repression of the PIK3CA sensor by drugs was inversely proportional to cellular p53 level in a germline (PA1) and in an EOC (A2780) cell line but not in a p53 deficient EOC (SKOV3) cell line. Bioluminescence imaging of tumor xenografts stably expressing the PIK3CA sensor in PA1 and A2780 cells exhibited attenuating activity without any change in SKOV3 tumors expressing the PIK3CA sensor after cisplatin treatment. Sequential mutation at p53 binding sites showed gradual increase in promoter activity and decreased effects of the drugs. These newly developed PIK3CA-fluc2-tdt and the mutant reporter sensors thus would be extremely useful for screening new drugs and for functional assessment of PIK3CA expression from intact cells to living subjects.  相似文献   
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Although remarkable results have been attained by adoptively transferring T cells expressing fully murine and/or humanized anti-CD19 chimeric antigen receptors (CARs) to treat B cell malignancies, evidence of human anti-mouse immune responses against CARs provides a rationale for the development of less immunogenic CARs. By developing a fully human CAR (huCAR), these human anti-mouse immune responses are likely eliminated. This, perhaps, not only increases the persistence of anti-CD19 CAR T cells—thereby reducing the risk of tumor relapse—but also facilitates administration of multiple, temporally separated doses of CAR T cells to the same recipient. To these ends, we have designed and constructed a second-generation fully human anti-CD19 CAR (or huCAR19) containing a fully human single-chain variable fragment (ScFv) fused with a CD8a hinge, a 4-1BB transmembrane domain and intracellular T cell signaling domains of 4-1BB and CD3z. T cells expressing this CAR specifically recognized and lysed CD19+ target cells produced cytokines and proliferated in vitro. Moreover, cell volume data revealed that our huCAR construct cannot induce antigen-independent tonic signaling in the absence of cognate antigen. Considering our results, our anti-CD19 huCAR may overcome issues of transgene immunogenicity that plague trials utilizing CARs containing mouse-derived ScFvs. These results suggest that this huCAR19 be safely and effectively applied for adaptive T cell immunotherapy in clinical practice.  相似文献   
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International Journal of Peptide Research and Therapeutics - One major issue in cancer immunotherapy is the large size of mAbs (150&nbsp;kDa) which usually causes limitation in tumor...  相似文献   
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