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1.
Economic botany, like botany, had its origin with the herbalists. Its development was encouraged by various European rulers during the Age of Exploration and Discovery in the 16th century. Recent developments in the United States include A. F. Hill’s textbook, Economic Botany, in 1937 the founding of the journal Economic Botany by E. H. Fulling in 1947 and the formation of the Society for Economic Botany in 1959 Some of the breakthroughs in the development of agriculture, beginning with its origin some 10,000 yr ago, are given. It is concluded that we now need another significant breakthrough to feed the world’s population adequately in the year 2000 Some look to genetic engineering to provide such a breakthrough.  相似文献   

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A combined taxonomic revision and wood anatomical study ofDicorynia, a South American genus of legumes that is unusual in both its floral and wood anatomy, is presented. Two possible evolutionary pathways leading to the unique 8-to 10-thecate anthers are discussed, and it is concluded that apical proliferation of the thecal primordia is the more likely. Gross and microscopic features of this silica-accumulating wood are given in detail and contrasted with other legume woods especially those containing silica. Economic uses of the trees, especially the wood ofD. guianensis, are discussed particularly in regard to marine construction. It is suggested that the high resistance of this wood to marine borers lies not so much in its silica content as to the presence of some other chemical. Based on the similarity of floral and fruit structures, the number of species is reduced from 7 to 2:D. guianensis in the Guianas andD. paraensis in the Amazonian region. Vegetative variations in the Amazonian population, previously given species rank, are reduced to 5 new varieties ofD. paraensis.  相似文献   

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This paper presents the activities and publications of Organisation for Economic Co-operation and Developments (OECD’s) Working Group on Harmonisation of Regulatory Oversight in Biotechnology and the Task Force for the Safety of Novel Foods and Feeds. The main outputs of the work are the Series of “consensus documents” of the respective groups. These documents compile information which is intended to be used by those involved in the business of risk/safety assessment. These documents are one means of ensuring the transportability of data amongst authorities. An increasing trend in both the Working Group and Task Force is to consider crop species which are relevant to tropical regions and therefore to countries that are not necessarily members of the OECD. For example, the Working Group has recently published a consensus document on bananas and plantains while the Task Force has published a document on cassava. This trend towards crops of greater interest in the tropics is likely to continue into the future.  相似文献   

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Codeine, medically the most widely used opiate, is mostly derived from morphine, isolated from opium and poppy straw (Papaver somniferum, opium poppy). Morphine, however, is greatly misused by illegal conversion into its diacetyl-derivative: heroin. The discovery of an efficient alternative medicine or a source for codeine other than opium poppy may contribute to a curtailment of the heroin market. No major adverse properties should be present in such a new medicine or codeine source. In this paper the search for the latter is discussed with regards to the natural occurrence of morphinan derivatives and the biosynthetic pathways in available plants. Economic and social problems connected with the introduction of a new biological source for opiates are reviewed.  相似文献   

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It has been described that A disintegrin and metalloproteinase (ADAM10) may involve in the physiopathology of prion diseases, but the direct molecular basis still remains unsolved. In this study, we confirmed that ADAM10 was able to cleave recombinant human prion protein in vitro. Using immunoprecipitation tests (IP) and immunofluorescent assays (IFA), reliable molecular interaction between the native cellular form of PrP (PrPC) and ADAM10 was observed not only in various cultured neuronal cell lines but also in brain homogenates of healthy hamsters and mice. Only mature ADAM10 (after removal of its prodomain) molecules showed the binding activity with the native PrPC. Remarkably more prion protein (PrP)-ADAM10 complexes were detected in the membrane fraction of cultured cells. In the scrapie-infected SMB cell model, the endogenous ADAM10 levels, especially the mature ADAM10, were significantly decreased in the fraction of cell membrane. IP and IFA tests of prion-infected SMB-S15 cells confirmed no detectable PrP-ADAM10 complex in the cellular lysates and PrP-ADAM10 co-localization on the cell surface. Furthermore, we demonstrated that the levels of ADAM10 in the brain homogenates of scrapie agent 263K-infected hamsters and agent ME7-infected mice were also almost diminished at the terminal stage, showing time-dependent decreases during the incubation period. Our data here provide the solid molecular basis for the endoproteolysis of ADAM10 on PrP molecules and interaction between ADAM10 and PrPC. Obvious loss of ADAM10 during prion infection in vitro and in vivo highlights that ADAM10 may play essential pathophysiological roles in prion replication and accumulation.  相似文献   

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The current large-scale meta-analysis was performed to reach a reliable conclusion on the association between X-ray repair cross-complementing 1 (xrcc1) rs1799782 and the development of lung cancer. Studies that investigated the association between rs1799782 and lung cancer risk were identified by searching PubMed. We calculated odds ratio (OR) with corresponding 95 % confidence interval (CI) for Trp/Trp vs Arg/Arg, Trp/Trp + Arg/Trp vs Arg/Arg, and Trp/Trp vs Arg/Trp + Arg/Arg contrast models. Combining all 25 studies, we yielded three summary ORs: 1.07 (95 % CI 0.92–1.23) for Trp/Trp vs Arg/Arg, 0.93 (95 % CI 0.87–1.00) for Trp/Trp + Arg/Trp vs Arg/Arg, and 1.08 (95 % CI 0.94–1.25) for Trp/Trp vs Arg/Trp + Arg/Arg, suggesting rs1799782 was not associated with overall risk of lung cancer. Strikingly, a significantly deceased risk was found among Caucasian populations (Trp/Trp + Arg/Trp vs Arg/Arg, OR = 0.86, 95 % CI 0.76–0.97). This study confirms that xrcc1 rs1799782 may lower the risk of lung cancer among Caucasians.  相似文献   

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Development of drug resistance is a challenging problem in cancer chemotherapy. It has been shown that basic fibroblast growth factor (bFGF) plays an important role in an epigenetic mechanism of drug resistance. We have isolated a bFGF binding peptide P7 with inhibitory activity against bFGF-induced proliferation of human gastric cancer cells by screening a phage display library. In this study, we found that P7 peptide also has efficacy of reversing bFGF-induced resistance to Adriamycin (ADM) in human gastric cancer cells. Further investigations with SGC-7901 cells revealed that inhibition of Akt activation triggered by bFGF, and reversal of bFGF-induced up-regulation of Bcl-2 and XIAP and down-regulation of Bax, contribute to P7 peptide counteracting the anti-apoptotic effect of bFGF, and further reversing bFGF-induced resistance to ADM. The results suggested that the bFGF-binding peptide may have therapeutic potential of drug resistance in gastric cancer.  相似文献   

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To investigate the expression of TNF-α, IFN-γ, TGF-β, and IL-4 in the spinal tuberculous focus and its relationship with the lesions type, severity, and bone destruction. The pathological samples of patients with spinal tuberculosis (TB) were divided into hyperplasia group and necrosis group according to their intra-operative and post-operative pathological findings. Normal bone tissues were taken as the control group. Pathology and expression of TNF-α, IFN-γ, TGF-β, and IL-4 in different tissues were compared among these three groups using immunohistochemical staining, quantitative image analysis, and measurement of bone tissue. 286 granulomas observed in the 14 samples in the hyperplasia group, which included 84 necrotizing and 202 non-necrotizing granulomas. As for the 20 samples in the necrosis group, there were 356 necrotizing and 186 non-necrotizing granulomas among all the 542 granulomas. The proportion of necrotizing granulomas in the necrosis group was significantly higher than that of the hyperplasia group. By inter-group comparison, expression of TNF-α, IFN-γ of granulomas in the hyperplasia group was significantly higher than that of the necrosis group, while the expression of TGF-β, IL-4 of granulomas in the necrosis group was significantly higher than that of the hyperplasia group. Also, expression of IFN-γ of non-necrotizing granulomas was significantly higher than that of necrotizing granulomas in the hyperplasia group, and expression of TGF-β in necrotizing granulomas was significantly higher than that of non-necrotizing granulomas in the necrosis group. The lesions were mainly bone resorption in the hyperplasia group, whereas mostly necrotic bones accompanied by local fibrosis in the necrosis group. Expression levels of TNF-α, IFN-γ in the hyperplasia group have a positive correlation to bone loss, whereas expression levels of TGF-β, IL-4 in the necrosis group have a positive correlation to the bone formation. The high expressions of TNF-α, IFN-γ in the spinal tuberculous focus were associated with protective immune cells. TGF-β and IL-4 were related to allergic lesions, fibrosis and osteogenesis. Expression imbalance of TNF-α, IFN-γ, TGF-β, and IL-4 might aggravate the allergy of TB.  相似文献   

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Esophageal squamous cell carcinoma (ESCC) is one of the most malignant tumors. The aim of this study was to investigate the biology characteristics of ESCC by analyzing microRNA and mRNA expression profile. We used BRB-array tools to analyze the deregulated microRNA and mRNA between esophageal squamous cell carcinomas and paired normal adjacent tissues. We used miRTrail and protein–protein interaction methods to explore the related pathways and networks of deregulated microRNA and mRNA. By combining the results of pathways and networks, we found that the deregulated microRNA and their deregulated target mRNA are enriched in the following pathways: DNA replication, cell cycle, ECM-receptor interaction, focal adhesion, mismatch repair, and pathways in cancer. The results showed that many deregulated microRNAs and mRNAs may play a vital role in the pathogenesis of ESCC, and the systems biology approach is very helpful to explore molecular mechanism of ESCC.  相似文献   

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Hepatocellular carcinoma (HCC) is a very aggressive neoplasia requiring early and accurate diagnosis to improve patient outcomes with timely treatment. The liver is also very frequently colonized by metastases, and the most frequent differential diagnosis is HCC against intrahepatic cholangiocarcinoma or metastatic adenocarcinoma. Metabolomics is a powerful tool for identification of altered biomarkers in cancer, and to evaluate the efficacy of drug treatments. Here we analyzed by HILIC-MS/MS methylated arginines, basic amino acids (Arg, Cit, Orn), and their ratios in the extracts of primary HCC tissues, liver metastases from colorectal carcinoma (MET), cirrhotic related hepatitis-C-virus (CIR), and non-cirrhotic normal liver (NT) adjacent tissues. We found high levels of Arg (p < 0.0001) and Arg/Orn (p < 0.01) in MET compared to other tissues. In MET, compared to NT and CIR, Arg concentration was fivefold higher, while in HCC it was twofold higher. ADMA increased twofold compared to NT and CIR, while in HCC it was 50 % higher. Arg/Cit and ADMA/SDMA ratios were significantly higher in MET compared to NT and CIR (p < 0.005). Arg/Orn, Arg/Cit, and ADMA/SDMA ratios increased progressively from NT, CIR, HCC, to MET tissues. Arg/Cit correlated significantly with Arg/Orn ratios (r = 0.77; p < 0.0001), and discriminates tumor from non-tumor samples. In addition, the discriminant lactate/glucose ratio we previously found by NMR, also correlated significantly with the Arg levels (r = 0.64; p < 0.0001), and discriminated MET from all other tissues. The results indicated that Arg in MET is higher than other tissue classes, suggesting that, together with the lactate/glucose ratio, it can be considered a further biomarker for HCC-metastases differentiation.  相似文献   

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An elevated level of tumor necrosis factor (TNF)-α is implicated in several cardiovascular diseases including heart failure. Numerous reports have demonstrated that TNF-α activates nuclear factor (NF)-kappaB, resulting in the upregulation of several genes that regulate inflammation, proliferation, and apoptosis of cardiomyocytes. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, a major source of reactive oxygen species (ROS), is also activated by TNF-α and plays a crucial role in redox-sensitive signaling pathways. The present study investigated whether NADPH oxidase mediates TNF-α-induced NF-kappaB activation and NF-kappaB-mediated gene expression. Human cardiomyocytes were treated with recombinant TNF-α with or without pretreatment with diphenyleneiodonium (DPI) and apocynin, inhibitors of NADPH oxidase. TNF-α-induced ROS production was measured using 5-(and-6)-chloromethyl-2’, 7’-dichlorodihydrofluorescein diacetate assay. TNF-α-induced NF-kappaB activation was also examined using immunoblot; NF-kappaB binding to its binding motif was determined using a Cignal reporter luciferase assay and an electrophoretic mobility shift assay. TNF-α-induced upregulation of interleukin (IL)-1β and vascular cell adhesion molecule (VCAM)-1 was investigated using real-time PCR and immunoblot. TNF-α-induced ROS production in cardiomyocytes was mediated by NADPH oxidase. Phosphorylation of IKK-α/β and p65, degradation of IkappaBα, binding of NF-kappaB to its binding motif, and upregulation of IL-1β and VCAM-1 induced by TNF-α were significantly attenuated by treatment with DPI and apocynin. Collectively, these findings demonstrate that NADPH oxidase plays a role in regulation of TNF-α-induced NF-kappaB activation and upregulation of proinflammatory cytokines, IL-1β and VCAM-1, in human cardiomyocytes.  相似文献   

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Vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) are important factors in tumor growth and metastasis. Molecular probes or drugs designed to target VEGF/VEGFR interactions are crucial in tumor molecular imaging and targeted therapy. Bioinformatic methods enable molecular design based on the structure of bio-macromolecules and their interactions. This study was aimed to identify tumor-targeting small-molecule peptides with high affinity for VEGFR using bioinformatics screening. The VEGFR extracellular immunoglobulin-like modules Ig1–Ig3 were used as the target to systematically alter the primary peptide sequence of VEGF125–136. Molecular docking and surface functional group interaction methods were combined in an in silico screen for polypeptides, which in theory, would have higher affinities for VEGFR. In vitro receptor competition binding assays were used to assess the affinity of the putative VEGFR-binding polypeptides. Rhodamine-conjugated peptides were used to label and visualize peptide-binding sites on A549 cells. Using bioinformatic screening, we identified 20 polypeptides with potentially higher affinity for VEGFR. The polypeptides were capable of inhibiting the binding of 125I-VEGF to VEGFR in a dose-dependent manner. The IC50 values of QKRKRKKSRKKH and RKRKRKKSRYIVLS (80 and 185 nmol/L, respectively) were significantly lower than that of VEGF125–136 (464 nmol/L); thus, the affinity of these peptides for VEGFR was 6- and 2.5-fold higher, respectively, than that of VEGF125–136. Rhodamine labeling of A549 cells revealed peptide binding mainly on the plasma membrane and in the cytoplasm. Bioinformatic approaches hold promise for the development of molecular imaging probes. Using this approach, we designed two peptides that showed higher affinity toward VEGFR. These polypeptides may be used as molecular probes or drugs targeting VEGFR, which can be utilized in molecular imaging and targeted therapy of certain tumors.  相似文献   

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This study was conducted to determine effects of dietary supplementation with 1 % l-glutamine for 14 days on the abundance of intestinal bacteria and the activation of intestinal innate immunity in mice. The measured variables included (1) the abundance of Bacteroidetes, Firmicutes, Lactobacillus, Streptococcus and Bifidobacterium in the lumen of the small intestine; (2) the expression of toll-like receptors (TLRs), pro-inflammatory cytokines, and antibacterial substances secreted by Paneth cells and goblet cells in the jejunum, ileum and colon; and (3) the activation of TLR4-nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPK), and phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt) signaling pathways in the jejunum and ileum. In the jejunum, glutamine supplementation decreased the abundance of Firmicutes, while increased mRNA levels for antibacterial substances in association with the activation of NF-κB and PI3K-Akt pathways. In the ileum, glutamine supplementation induced a shift in the Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes, and enhanced mRNA levels for Tlr4, pro-inflammatory cytokines, and antibacterial substances participating in NF-κB and JNK signaling pathways. These results indicate that the effects of glutamine on the intestine vary with its segments and compartments. Collectively, dietary glutamine supplementation of mice beneficially alters intestinal bacterial community and activates the innate immunity in the small intestine through NF-κB, MAPK and PI3K-Akt signaling pathways.  相似文献   

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