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Loss of chloroplast-localized NAD kinase causes ROS stress in Arabidopsis thaliana. JOURNAL OF PLANT RESEARCH 2023; 136:97-106. [PMID: 36367584 DOI: 10.1007/s10265-022-01420-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Chloroplast-localized NAD kinase (NADK2) is responsible for the production of NADP+, which is an electron acceptor in the linear electron flow of photosynthesis. The Arabidopsis T-DNA-inserted mutant of NADK2 (nadk2) showed delayed growth and pale-green leaves under continuous light conditions. Under short-day conditions (8 h light / 16 h dark), the nadk2 mutant showed more severe growth inhibition.The genomic fragment containing the promoter and coding region of NADK2 complemented the phenotypes of nadk2 obtained under continuous light and short-day conditions. The nadk2 mutant produced higher amounts of H2O2 and O2-, which were reduced in the complementary line. Under short-day conditions, the nadk2 mutant accumulated more H2O2 than under continuous light conditions. The accumulation of ascorbate and up-regulation of the PDF1.2 and PR1 genes indicated that the nadk2 mutant is under ROS stress and responding to keep its living activities.
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Overexpression of nicotinamidase 3 (NIC3) gene and the exogenous application of nicotinic acid (NA) enhance drought tolerance and increase biomass in Arabidopsis. PLANT MOLECULAR BIOLOGY 2021; 107:63-84. [PMID: 34460049 DOI: 10.1007/s11103-021-01179-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/02/2021] [Indexed: 05/27/2023]
Abstract
Overexpressing Nicotinamidase 3 gene, and the exogenous application of its metabolite nicotinic acid (NA), enhance drought stress tolerance and increase biomass in Arabidopsis thaliana. With progressive global climatic changes, plant productivity is threatened severely by drought stress. Deciphering the molecular mechanisms regarding genes responsible for balancing plant growth and stress amelioration could imply multiple possibilities for future sustainable goals. Nicotinamide adenine dinucleotide (NAD) biosynthesis and recycling/ distribution is a crucial feature for plant growth. The current study focuses on the functional characterization of nicotinamidase 3 (NIC3) gene, which is involved in the biochemical conversion of nicotinamide (NAM) to nicotinic acid (NA) in the salvage pathway of NAD biosynthesis. Our data show that overexpression of NIC3 gene enhances drought stress tolerance and increases plant growth. NIC3-OX plants accumulated more NA as compared to WT plants. Moreover, the upregulation of several genes related to plant growth/stress tolerance indicates that regulating the NAD salvage pathway could significantly enhance plant growth and drought stress tolerance. The exogenous application of nicotinic acid (NA) showed a similar phenotype as the effect of overexpressing NIC3 gene. In short, we contemplated the role of NIC3 gene and NA application in drought stress tolerance and plant growth. Our results would be helpful in engineering plants with enhanced drought stress tolerance and increased growth potential.
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Preclinical study of rAAV2-sTRAIL: pharmaceutical efficacy, biodistribution and safety in animals. Cancer Gene Ther 2017; 24:251-258. [PMID: 28429751 DOI: 10.1038/cgt.2017.12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 02/02/2017] [Accepted: 03/07/2017] [Indexed: 12/31/2022]
Abstract
The recombinant sTRAIL has been in clinical trial for various human malignancies. However, the half-life time of sTRAIL is very short, which might be an important factor influencing its clinical efficacy for cancer therapy. We previously reported the recombinant adeno-associated virus (AAV)-encoding sTRAIL95-281-mediated sTRAIL expression in vivo up to 8 months and suppressed tumor growth markedly in mouse xenografts. In the present study, we further evaluated the clinical potency for cancer gene therapy and the safety in mouse and non-human primates. The mouse models with HCT-116, NCI-H460 and BEL-7402 cancers were injected intraperitoneally with a single dose of 1.0 × 1011, 1.0 × 1010 and 1.0 × 109 vg of rAAV2-sTRAIL95-281 virus, respectively. The cynomolgus monkeys were injected (i.m.) with a single dose of rAAV2-sTRAIL95-281 of 1 × 1011, 3 × 1011 and 1 × 1012 vg, corresponding to 6-, 20- and 60-fold of intended use dosage for humans, respectively. The efficacy, pharmacology and toxicity of rAAV-sTRAIL in the animals were analyzed accordingly. The tumor inhibitory rates reached 44-76%, 48-52% and 55-74% in the three tumor models, respectively, and they had no influence on mouse spontaneous activity. Administration (s.c.) of a single dose of rAAV2-sTRAIL95-281 virus of 1.0 × 109 or 1.0 × 1010 vg in mice with implanted tumor led to mainly distribution in the spleen, liver, implanted tumor, blood, injected site of muscle and bone marrow. Two weeks later, there was no rAAV2-sTRAIL95-281 detected in blood and bone marrow, and it significantly decreased in other tissues and organs and then gradually cleared away in 4-12 weeks after administration. There was no rAAV2-sTRAIL accumulation in the animal's body and no influence on the body weights. Administration (i.v.) did not cause animal death, and no dose-related abnormal clinical symptoms were found in the mice. There were no abnormal tissue and organ found in all animals. Long-term toxicity test in cynomolgus monkeys did not cause rAAV2-sTRAIL95-281-related toxic and side effects, except that anti-AAV and anti-sTRAIL antibodies were generated. In conclusion, these data demonstrated that administration of rAAV2-sTRAIL95-281 in mice and in cynomolgus monkeys is safe without obvious toxic and side effects to the animals, and throw light on pharmacokinetics and safety in human clinical trials for cancer gene therapy.
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SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT. II.SWIFTANDHSTREVERBERATION MAPPING OF THE ACCRETION DISK OF NGC 5548. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/806/1/129] [Citation(s) in RCA: 170] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT. I. ULTRAVIOLET OBSERVATIONS OF THE SEYFERT 1 GALAXY NGC 5548 WITH THE COSMIC ORIGINS SPECTROGRAPH ONHUBBLE SPACE TELESCOPE. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/806/1/128] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Pre-clinical efficacy of combined therapy with novel β-catenin antagonist BC2059 and histone deacetylase inhibitor against AML cells. Leukemia 2014; 29:1267-78. [PMID: 25482131 PMCID: PMC4456205 DOI: 10.1038/leu.2014.340] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 10/10/2014] [Accepted: 10/16/2014] [Indexed: 12/15/2022]
Abstract
The canonical WNT-β-catenin pathway is essential for self-renewal, growth and survival of AML stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of β-catenin, causing increased nuclear translocation and co-factor activity of β-catenin with the transcriptional regulator TCF4/LEF1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate β-catenin levels. BC treatment disrupted the binding of β-catenin with the scaffold protein TBL1 (transducin β-like 1) and proteasomal degradation and decline in the nuclear levels of β-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs exhibiting nuclear expression of β-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD.
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Erratum: Comprehensive gene expression profiling and immunohistochemical studies support application of immunophenotypic algorithm for molecular subtype classification in diffuse large B-cell lymphoma: a report from the International DLBCL Rituximab-CHOP Consortium Program Study. Leukemia 2014. [DOI: 10.1038/leu.2014.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Effects of Upper Esophageal Sphincter Dilation on Patients Postradiation. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2013.11.141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Effects of UES Dilatation on Head-and-Neck Cancer Patients Post-Radiation Therapy. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.1169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Hypocrea lixii, novel endophytic fungi producing anticancer agent cajanol, isolated from pigeon pea (Cajanus cajan [L.] Millsp.). J Appl Microbiol 2013; 115:102-13. [PMID: 23495919 DOI: 10.1111/jam.12195] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 03/01/2013] [Accepted: 03/11/2013] [Indexed: 11/30/2022]
Abstract
AIMS The aim was to isolate, identify and characterize endophytes from pigeon pea (Cajanus cajan [L.] Millsp.), as novel producer of cajanol and its in vitro cytotoxicity assay. METHODS AND RESULTS Isolation, identification and characterization of novel endophytes producing cajanol from the roots of pigeon pea were investigated. The endophytes were identified as Hypocrea lixii by morphological and molecular methods. Cajanol produced by endophytes were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). R-18 produced the highest levels of cajanol (322·4 ± 10·6 μg l(-1) or 102·8 ± 6·9 μg g(-1) dry weight of mycelium) after incubation for 7 days. The cytotoxicity towards human lung carcinoma cells (A549) of fungal cajanol was investigated in vitro. CONCLUSIONS First, a novel endophyte Hypocrea lixii, producing anticancer agent cajanol, was isolated from the host pigeon pea (Cajanus cajan [L.] Millsp.). Fungal cajanol possessed stronger cytotoxicity activity towards A549 cells in time- and dose-dependent manners. SIGNIFICANCE AND IMPACT OF THE STUDY This endophyte is a potential handle for scientific and commercial exploitation, and it could provide a promising alterative approach for large-scale production of cajanol to satisfy new anticancer drug development.
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Micronization of the Pharmaceutically Active Agent Genipin by an Antisolvent Precipitation Process. Chem Eng Technol 2012. [DOI: 10.1002/ceat.201200036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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13
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Controllable thermal expansion properties of In2 −xCrxMo3O12. CRYSTAL RESEARCH AND TECHNOLOGY 2012. [DOI: 10.1002/crat.201200080] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Comprehensive gene expression profiling and immunohistochemical studies support application of immunophenotypic algorithm for molecular subtype classification in diffuse large B-cell lymphoma: a report from the International DLBCL Rituximab-CHOP Consortium Program Study. Leukemia 2012; 26:2103-13. [PMID: 22437443 DOI: 10.1038/leu.2012.83] [Citation(s) in RCA: 255] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Gene expression profiling (GEP) has stratified diffuse large B-cell lymphoma (DLBCL) into molecular subgroups that correspond to different stages of lymphocyte development-namely germinal center B-cell like and activated B-cell like. This classification has prognostic significance, but GEP is expensive and not readily applicable into daily practice, which has lead to immunohistochemical algorithms proposed as a surrogate for GEP analysis. We assembled tissue microarrays from 475 de novo DLBCL patients who were treated with rituximab-CHOP chemotherapy. All cases were successfully profiled by GEP on formalin-fixed, paraffin-embedded tissue samples. Sections were stained with antibodies reactive with CD10, GCET1, FOXP1, MUM1 and BCL6 and cases were classified following a rationale of sequential steps of differentiation of B cells. Cutoffs for each marker were obtained using receiver-operating characteristic curves, obviating the need for any arbitrary method. An algorithm based on the expression of CD10, FOXP1 and BCL6 was developed that had a simpler structure than other recently proposed algorithms and 92.6% concordance with GEP. In multivariate analysis, both the International Prognostic Index and our proposed algorithm were significant independent predictors of progression-free and overall survival. In conclusion, this algorithm effectively predicts prognosis of DLBCL patients matching GEP subgroups in the era of rituximab therapy.
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Transfection of shRNA-encoding Minivector DNA of a few hundred base pairs to regulate gene expression in lymphoma cells. Gene Ther 2010; 18:220-4. [PMID: 20962872 PMCID: PMC3154479 DOI: 10.1038/gt.2010.123] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This work illustrates the utility of Minivector DNA, a non-viral, supercoiled gene therapy vector incorporating short hairpin RNA from an H1 promoter. Minivector DNA is superior to both plasmid DNA and small interfering RNA (siRNA) in that it has improved biostability while maintaining high cell transfection efficiency and gene silencing capacity. Minivector DNAs were stable for over 48 h in human serum, as compared with only 0.5 and 2 h for siRNA and plasmid, respectively. Although all three nucleic acids exhibited similar transfection efficiencies in easily transfected adhesion fibroblasts cells, only Minivector DNAs and siRNA were capable of transfecting difficult-to-transfect suspension lymphoma cells. Minivector DNA and siRNA were capable of silencing the gene encoding anaplastic lymphoma kinase, a key pathogenic factor of human anaplastic large cell lymphoma, and this silencing caused inhibition of the lymphoma cells. Based on these results, Minivector DNAs are a promising new gene therapy tool.
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The T helper type 17/regulatory T cell imbalance in patients with acute Kawasaki disease. Clin Exp Immunol 2010; 162:131-7. [PMID: 20718783 DOI: 10.1111/j.1365-2249.2010.04236.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The study is designed to investigate the changes and roles of T helper type 17/regulatory T cells (Th17/T(reg) ) in the immunological pathogenesis of Kawasaki disease (KD). In addition, we explore the alteration and significance of Th17 cells in patients with intravenous immune globulin-resistant KD. Real-time polymerase chain reaction (PCR) was used to evaluate the mRNA levels of interleukin (IL)-17A/F, retinoic acid-related orphan receptor (ROR)-γt and forkhead box P3 (FoxP3) in CD4-positive cells. The proportions of Th17 cells and CD4(+) CD25(+) FoxP3(high) T(regs) were analysed by flow cytometry. Plasma cytokine [IL-17A, IL-6, IL-23 and transforming growth factor (TGF)-β] concentrations were measured by sandwich enzyme-linked immunosorbent assay. Our data demonstrate that Th17 proportions and expression levels of cytokines (IL-17, IL-6 and IL-23) and transcription factors (IL-17A/F, ROR-γt) were up-regulated significantly, while T(reg) proportions and expression levels of T(reg ) transcription factor (FoxP3) were down-regulated significantly in children with acute KD (P<0·01). Compared with the sensitive group, the Th17 proportions were up-regulated significantly during the acute phase in immune globulin-resistant KD (P < 0·01). The plasma IL-17A, IL-6 and IL-23 concentrations in patients with KD were significantly higher compared with the concentrations in normal controls (NC) and infectious disease (ID). Plasma TGF-β concentrations were markedly lower in the KD group than the NC and ID groups (P < 0·05). These results suggest that Th17/T(reg) cells imbalance exists in the patients with KD. Th17/T cells imbalance may be important factors causing disturbed immunological function and resulting in immunoglobulin-resistant KD.
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Synergistic growth inhibition of anaplastic large cell lymphoma cells by combining cellular ALK gene silencing and a low dose of the kinase inhibitor U0126. Cancer Gene Ther 2010; 17:633-44. [PMID: 20448669 PMCID: PMC2919633 DOI: 10.1038/cgt.2010.20] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Abnormal expression of anaplastic lymphoma kinase (ALK) gene is an important pathogenic factor for anaplastic large cell lymphoma (ALCL). To study the function of ALK, an inducible short hairpin RNA (shRNA) system was stably introduced into cultured human ALCL cells. Inducing shRNA expression in the generated cells resulted in cellular ALK gene silencing and led to inactivation of multiple signaling pathways and growth arrest. Interestingly, a combination of ALK gene silencing with U0126, a kinase inhibitor specific for the extracellular signal-regulated kinases 1/2 pathway, resulted in an augmented reduction in cellular JunB expression. Functional studies indicated that combining ALK gene silencing with U0126 treatment provided a synergistic growth inhibition, which occurred faster and was more profound than with either treatment alone. This synergistic effect was also observed when measuring cell proliferation, apoptosis, and in vitro cell colony formation. Importantly, the combination of ALK gene silencing and U0126 had a prolonged inhibitory effect, preventing recovery of ALCL cell growth even after treatments were removed. Moreover, this synergistic inhibitory effect was confirmed in vivo using a mouse model with xenografted ALCL tumors. Our findings indicate that combining cellular ALK gene silencing with a low dose of U0126 may prove to be an effective and more specific therapeutic approach to treating ALCL.
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Medicinal chemistry of paclitaxel and its analogues. Curr Med Chem 2010; 16:3966-85. [PMID: 19747129 DOI: 10.2174/092986709789352277] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Accepted: 07/29/2009] [Indexed: 12/13/2022]
Abstract
Paclitaxel belongs to the most successful anticancer drugs developed and utilised during the past two decades. Nevertheless, the development of resistance of tumor cells and severe side effects in the patients require further improvement of the drug. In this review, we provide a detailed overview of the state-of-the-art in the medicinal chemistry of paclitaxel and its analogues. A number of strategies have been explored to obtain sufficient amounts of paclitaxel for clinical use from natural resources. Semi-synthesis from its precursor, 10-deacetylbaccatin III, which can be extracted from Taxus leavesturned out as the most appropriate method for commercial production. So far, many paclitaxel derivatives have been synthesized, and their effect on microtubules stabilization and cytotoxicity were investigated in terms of structure-activity relationships (SAR). One of them, docetaxel, was approved as a more potent anticancer agent than paclitaxel towards a variety of tumor types. This review summarizes current possibilities to harvest sufficient amount of drugs from natural sources, including the production of taxanes in bioreactors and synthetic approaches for paclitaxel and its analogues, their mechanism of action and structure-activity relationships. In addition, future developments and perspectives for this class of compounds are outlined.
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Complete thermodynamic characterization of reduction and protonation of the bc(1)-type Rieske [2Fe-2S] center of Thermus thermophilus. J Am Chem Soc 2001; 123:9906-7. [PMID: 11583559 DOI: 10.1021/ja016532c] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Electrogenerated chemiluminescence. 67. Dependence of light emission of the tris(2,2')bipyridylruthenium(II)/tripropylamine system on electrode surface hydrophobicity. Anal Chem 2001; 73:3960-4. [PMID: 11534723 DOI: 10.1021/ac010230b] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe the effect of electrode surface hydrophobicity on the electrochemical behavior and electrogenerated chemiluminescence (ECL) of Ru(bpy)3(2+) (bpy = 2,2'-bipyridyl)/tripropylamine (TPrA) system. Gold and platinum electrodes were modified with different thiol monolayers. The hydrophobicity of the electrode surfaces changed with different terminal groups of the thiol molecules. The oxidation rate of TPrA was found to be much larger at the modified electrode with a more hydrophobic surface. The adsorption of neutral TPrA species on this kind of surface was assumed to contribute to the faster anodic kinetics. Due to the rapid generation of the highly reducing radical, TPrA., ECL intensity increased significantly at more hydrophobic electrodes. This electrode surface effect in the ECL analytical system allows one to improve the detection sensitivity at low concentrations of Ru(bpy)3(2+). The surfactant effect on the ECL process was also examined and discussed based on the change of electrode hydrophobicity by the adsorption of surfactant species.
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Scanning optical microscopy with an electrogenerated chemiluminescent light source at a nanometer tip. Anal Chem 2001; 73:2153-6. [PMID: 11393834 DOI: 10.1021/ac001538q] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electrogenerated chemiluminescence at electrodes with effective diameters down to 155 nm was used as a stable light source for near-field scanning optical microscopy imaging of an interdigitated array and a submicrometer size test substrate. Light was generated in a thin (approximately 500 microm) layer of an aqueous solution of 15 mM Ru(bpy)3(2+) and 100 mM tri-n-propylamine in a pH 7.5 buffer. The resolution obtained was compared to that found with a micrometer size electrode. The shear force from the tip attached to a quartz tuning fork was used to monitor and control the tip-to-substrate separation within the near field regime.
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[Effect of enhanced UV-B radiation on chemical composition, fungal colonization and decomposition of spring wheat plant]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2001; 12:223-5. [PMID: 11757366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Under UV-B radiation, the CHO (soluble carbohydrate) concentration in leaves decreased significantly, while the concentrations of HCel (holocellulose) and protein in leaves and that of HCel in stems increased significantly. HCel concentration in roots did not change significantly. Under UV-B radiation, the colonization rates of Penicillium ochro-chloron and Aspergillus niger on leaves and stems increased significantly during growing phase, those of Trichoderma koningii and Aureobasidium pullulans were on the contrary, while that of Aspergillus terreus did not change obviously. After 60 and 100 days of decomposition, the decomposition rates of leaves and stems increased significantly. The decomposition rate of leaves was positively correlated with the concentration of HCel and soluble protein, but negatively with that of CHO. The decomposition rate of stems was also positively correlated with HCel concentration. Under enhanced UV-B radiation, the changes in chemical composition of spring wheat and in fungal colonization rate, and the increase in decomposition rates might resulted in a faster nutrient turnover in wheat field ecosystem and a higher nutrient storage in soil.
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Chromosomal abnormalities and p53 gene mutation in a cardiac angiosarcoma. Appl Immunohistochem Mol Morphol 2001; 9:24-8. [PMID: 11277410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Angiosarcoma is the most common malignant neoplasm of the heart. However, to the authors' knowledge, no cytogenetic study of cardiac angiosarcoma has been reported. In the current study, an angiosarcoma from the right atrium of a 29-year-old man was investigated. Examination of tissue sections indicated that the tumor was a high grade epithelioid angiosarcoma of the heart. Cytogenetic analysis of tumor cells revealed a hyperdiploid clonal population with chromosomal numerical changes and one structural rearrangement, which was defined as: 55, XY, +der(1;17) (q10:q10), +2, +7, +8, +8, +19, +20, +21, +22. Multicolor fluorescent in situ hybridization on paraffin-embedded tissue sections illustrated polysomy of chromosome 8 in tumor cells. In addition, immunohistochemical analysis showed high expression of mutated p53 gene products in tumor cell nuclei. These findings demonstrate the involvement of chromosomal anomalies and gene mutation in cardiac angiosarcoma and suggest they play a role in neoplasia of the heart.
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Cadmium response of the hairy root culture of the endangered species Adenophora lobophylla. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2001; 160:551-562. [PMID: 11166443 DOI: 10.1016/s0168-9452(00)00429-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We generated hairy root cultures from two closely related species, Adenophora lobophylla and A. potaninii (Campanulaeae) and carried out a comparative study on their cadmium (Cd) response. A. lobophylla is an endangered species while A. potaninii is widely distributed in the same habitat. Upon exposure to Cd concentrations higher than 50 µM, more extensive growth inhibition and higher Cd accumulation were detected in the hairy root of A. lobophylla. Cd treatment affected the protein content in both the species. Phytochelatins (PCs) have been isolated and characterized from the hairy roots for both species. They shared structure similarities but showed different accumulation kinetics. The content of reduced glutathione (GSH) and cysteine (Cys) differs in both the species and they show different changes upon Cd challenge. The results suggested that these two species might employ different strategy for Cd detoxification. A. lobophylla is capable of synthesizing high level of PCs while a Cd exclusion system and a tighter homeostasis mechanism(s) to maintain the cellular GSH level could have been evolved in A. potanini in additon to its capability of synthesizing PCs.
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Light microscopic and ultrastructural evidence of in vivo phagocytosis of Helicobacter pylori by neutrophils. Ultrastruct Pathol 2000; 24:319-23. [PMID: 11071570 DOI: 10.1080/019131200750035049] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Helicobacter pylori is believed to cause chronic active gastritis. Infection/colonization of the gastric mucosal surface induces a mucosal inflammatory reaction in the form of lymphocytic aggregates, plasma cells and, particularly, neutrophils, which may, in turn, damage the mucosal epithelium. In vitro studies demonstrate that, in culture, the bacilli are readily phagocytosed by neutrophils, this evoking a neutrophilic oxidative burst. However, it has been claimed that neutrophils do not phagocytose H. pylori in vivo. In this study of 19 endoscopic biopsies of gastric mucosa with H. pylori-associated gastritis, Cresyl violet staining for light microscopy and electron microscopy are used to demonstrate that, in vivo, neutrophils actively phagocytose and destroy the bacilli in the epithelial intercellular space and in the mucin on the surface of the mucosa. Direct contact of neutrophils with H. pylori was observed in 17 of 17 cases by light microscopy and in 4 of 15 cases by electron microscopy. Phagocytosis by neutrophils was seen in 14 of 17 cases by light microscopy and in 3 of 1 5 cases by electron microscopy. It was most evident in the surface mucus coat where "wolf packs" of neutrophils were seen attacking the microbes. Ultrastructurally, neutrophil phagolysosomes contained both intact and partially digested bacteria, convincing evidence that the primary function of neutrophils in chronic active gastritis is to destroy H. pylori organisms. This study leaves open the question of whether, or how, neutrophils damage the gastric mucosa.
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Abstract
The amino acid sequences deduced from cDNA analyses revealed that human leucocyte L-plastin phosphorylated in response to interleukin 1, 2 closely resembles a chicken intestinal microvilli protein, fimbrin, that bundles actin filaments [de Arruda et al. (1990) J. Cell Biol. 111, 1069-1079]. In the present work, it was observed that unphosphorylated L-plastin isolated from human T cells bundled F-actin just as fimbrin does. L-Plastin acted on T cell beta-actin, but hardly acted on muscle alpha-actin or chicken gizzard gamma-actin, whereas fimbrin bundled muscle alpha-actin. Unlike fimbrin, L-plastin's actin-bundling action was strictly calcium-dependent: the bundles were formed at pCa 7, but not at pCa 6. Under suitable conditions, approximately one molecule of L-plastin bound to 8 molecules of actin monomer in the actin filament.
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Abstract
Three murine monoclonal antibodies, designated GA-17, GB-4, and GC-3, were prepared by the hybridization of murine myeloma cells (NS-1) and spleen cells of BALB/c mice immunized with the crude membrane fraction of cultured human gliosarcoma cells (GI-1). Two of them (GA-17 and GB-4) reacted exclusively with the membrane of glioma cells, and the other (GC-3) reacted with the membrane of glioma cells and a T cell line (MOLT-4). Although these antibodies reacted with almost all of the gliomas, the reactions differed. GA-17 reacted equally well with all glioblastoma (17 cases) and low-grade astrocytoma (10 cases), whereas GB-4 reacted poorly with 7 cases of glioblastoma and GC-3 did not react with 7 cases of low-grade astrocytoma. The antigens, exclusively expressed on the cell surface, were analyzed by surface labeling with 125I followed by a cell lysis and immunoprecipitation with these antibodies. The findings obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that GA-17, GB-4, and GC-3 reacted with Mr 140,000-145,000, Mr 160,000, and Mr 145,000-150,000 proteins, respectively. Some evidence has been obtained indicating that these antigens are composed of the same polypeptide chain (Mr 120,000) with the carbohydrate chains being different.
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Characterization of interleukin 2 stimulated 65-kilodalton phosphoprotein in human T cells. Biochemistry 1990; 29:1055-62. [PMID: 2111166 DOI: 10.1021/bi00456a030] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We have characterized the cellular proteins which are rapidly phosphorylated by interleukin 2 (IL 2) in a human IL 2 dependent cell line. When treated with IL 2, the phosphorylation of five proteins, 65, 50, 37, 24, and 21 kDa, was found in IL 2 dependent cell lines by two-dimensional gel electrophoretic analysis. After cell conversion from an IL 2 dependent state to an IL 2 independent state, one of the five phosphoproteins, the 65-kDa protein, became constitutively phosphorylated even without addition of IL 2. Also, in other IL 2 independent cell lines, such as KUT-2 and HUT-102, constitutive phosphorylation of the 65-kDa protein occurred without IL 2-stimulation. So our researchers were focused on biochemical characterization of the 65-kDa protein. It was found that the 65-kDa protein was one of the major cellular proteins by comparing the results of two-dimensional gel electrophoretic analysis of [32P]Pi-labeled and [3H]leucine-labeled cellular proteins and peptide mapping analysis. Subcellular fractionation studies indicated that the 65-kDa protein is a cytosol protein. The 65-kDa protein was purified from cytosol of a human T cell line, and its amino acid composition and amino acid sequences of its three oligopeptides were determined. It was found that the 65-kDa protein is identical with 1-plastin.
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Persistent and enhanced expression of c-fos gene products in various kinds of human hematopoietic cell lines. Immunofluorescence study using prepared monoclonal antibodies. ACTA PATHOLOGICA JAPONICA 1988; 38:1523-36. [PMID: 3071079 DOI: 10.1111/j.1440-1827.1988.tb02292.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Two kinds of monoclonal antibodies recognizing fos proto-oncogene (c-fos) products were prepared using a synthetic oligopeptide corresponding to amino acids 127-152 of the fos oncogene products. These monoclonal antibodies (FO-120 & FO-145) detected fos gene products induced in a human monocyte cell line (U-937) by phorbol acetate (TPA) and induced in both human and mouse fibroblast cell lines (284, BALB/c 3T3) by serum-stimulation. One of the monoclonal antibodies (FO-120) reacted with 50-kDa and 42-kDa proteins and the other antibody (FO-145) reacted with a 30-33-kDa protein. The expression of the fos gene in various human hematopoietic cell lines was investigated using these prepared monoclonal antibodies. While almost all hematopoietic cell lines tested reacted with these monoclonal antibodies to various degrees, the majority of normal peripheral blood lymphocytes cultured with lectin (PHA) and interleukin 2 (IL-2) did not, suggesting that cells of some permanent hematopoietic cell lines, irrespective of their lineage specificity and growth factor dependency, continuously express the fos oncogene. These monoclonal antibodies may be useful for detecting early neoplastic changes in hematopoietic cells.
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Augmentation of tumor targeting in a line of glioma-specific mouse cytotoxic T-lymphocytes by retroviral expression of mouse gamma-interferon complementary DNA. Cancer Res 1988; 48:4730-5. [PMID: 3136912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
As an initial approach to experiments directed toward effective adoptive immunotherapy for cancer using lymphokine genes, we transferred retrovirally a complementary DNA encoding mouse gamma-interferon (IFN-gamma) into a specific cytotoxic T-lymphocyte clone, designated E-4, against 203 glioma cells (a 20-methylcholanthrene-induced mouse glioma line) and confirmed the efficacy of IFN-gamma production from the exogenous gene on augmentation of tumor targeting. Of five, two gene-transferred subclones constitutively produced 8 to 10 times the amount of IFN-gamma as compared with the parental E-4. Correspondingly, these two subclones exhibited 2 to 3 times higher killing activity against 203 glioma than the parental cells; the enhancement of the killing activities was abrogated by an adequate addition of anti-IFN-gamma antibody. No alteration was seen after the gene transfer in cell surface phenotypes, Thy-1+, Lyt-1-, Lyt-2+,3+, and asialo-GM1-. The surface expression of a major histocompatibility complex Class I antigen, H-2Kb, was not altered remarkably, but the Class II antigen, I-Ab, was partially and slightly enhanced on the two IFN-gamma-producing sublines mentioned above on fluorescence-activated cell sorter analysis. Since it is considered that in the vicinity of the constitutively IFN-gamma producing cytotoxic T-lymphocyte cells tumor cells are exposed to a high concentration of IFN-gamma, the cells may be stimulated to induce or enhance the expression of surface antigens including major histocompatibility complex antigens as well as tumor-associated antigens relevant to immune recognition. The 203 glioma cells pretreated with IFN-gamma were more efficiently killed by both the parental E-4 and the gene-transferred sublines. Taken together, the results suggested that the augmented specific tumor-killing activity of our gene-transferred cytotoxic T-lymphocytes was ascribed to the constitutive production of IFN-gamma derived from the exogenous gene.
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[Acute mushroom poisoning with Amanita virose]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1987; 21:335-7. [PMID: 3452511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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