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1.
AB Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(4):261-268
Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight. 相似文献
2.
Background
Organisms are capable of developing different phenotypes by altering the genes they express. This phenotypic plasticity provides a means for species to respond effectively to environmental conditions. One of the most dramatic examples of phenotypic plasticity occurs in the highly social hymenopteran insects (ants, social bees, and social wasps), where distinct castes and sexes all arise from the same genes. To elucidate how variation in patterns of gene expression affects phenotypic variation, we conducted a study to simultaneously address the influence of developmental stage, sex, and caste on patterns of gene expression in Vespula wasps. Furthermore, we compared the patterns found in this species to those found in other taxa in order to investigate how variation in gene expression leads to phenotypic evolution. 相似文献3.
Athanasiou A Clarke AB Turner AE Kumaran NM Vakilpour S Smith PA Bagiokou D Bradshaw TD Westwell AD Fang L Lobo DN Constantinescu CS Calabrese V Loesch A Alexander SP Clothier RH Kendall DA Bates TE 《Biochemical and biophysical research communications》2007,364(1):131-137
Time-lapse microscopy of human lung cancer (H460) cells showed that the endogenous cannabinoid anandamide (AEA), the phyto-cannabinoid Δ-9-tetrahydrocannabinol (THC) and a synthetic cannabinoid HU 210 all caused morphological changes characteristic of apoptosis. Janus green assays of H460 cell viability showed that AEA and THC caused significant increases in OD 595 nm at lower concentrations (10-50 μM) and significant decreases at 100 μM, whilst HU 210 caused significant decreases at all concentrations. In rat heart mitochondria, all three ligands caused significant decreases in oxygen consumption and mitochondrial membrane potential. THC and HU 210 caused significant increases in mitochondrial hydrogen peroxide production, whereas AEA was without significant effect. All three ligands induced biphasic changes in either mitochondrial complex I activity and/or mitochondrial complex II-III activity. These data demonstrate that AEA, THC, and HU 210 are all able to cause changes in integrated mitochondrial function, directly, in the absence of cannabinoid receptors. 相似文献
4.
A novel class of chiral peptide nucleic acids has been synthesized in which the sugar-phosphate backbone of DNA has been replaced with the glycyl-proline backbone of both the
- and the
-configurations, nucleobases being attached through the 4-position of proline withcis- andtrans-stereochemistry. TheT10homopolymers withcis-stereochemistry in the
- and
-series bind strongly to poly(dA) withTmvalues of 69 and 70°C, respectively. They bind more strongly to poly(rA) withTmvalues of 73 and 72°C, respectively, and with apparent 1:1 stoichiometry. Using a mixed sequence decamer it was found that the thermal stability of the chiral peptide nucleic acid/oligonucleotide complex was comparable to that formed by Nielsen's polyamide nucleic acid. 相似文献
5.
Ballard C Lana MM Theodoulou M Douglas S McShane R Jacoby R Kossakowski K Yu LM Juszczak E;Investigators DART AD 《PLoS medicine》2008,5(4):e76
Background
There have been increasing concerns regarding the safety and efficacy of neuroleptics in people with dementia, but there are very few long-term trials to inform clinical practice. The aim of this study was to determine the impact of long-term treatment with neuroleptic agents upon global cognitive decline and neuropsychiatric symptoms in patients with Alzheimer disease.Methods and Findings
Design: Randomised, blinded, placebo-controlled parallel two-group treatment discontinuation trial.Setting: Oxfordshire, Newcastle and Gateshead, London and Edinburgh, United Kingdom.Participants: Patients currently prescribed the neuroleptics thioridazine, chlorpromazine, haloperidol trifluoperazine or risperidone for behavioural or psychiatric disturbance in dementia for at least 3 mo.Interventions: Continue neuroleptic treatment for 12 mo or switch to an identical placebo.Outcome measures: Primary outcome was total Severe Impairment Battery (SIB) score. Neuropsychiatric symptoms were evaluated with the Neuropsychiatric Inventory (NPI).Results: 165 patients were randomised (83 to continue treatment and 82 to placebo, i.e., discontinue treatment), of whom 128 (78%) commenced treatment (64 continue/64 placebo). Of those, 26 were lost to follow-up (13 per arm), resulting in 51 patients per arm analysed for the primary outcome. There was no significant difference between the continue treatment and placebo groups in the estimated mean change in SIB scores between baseline and 6 mo; estimated mean difference in deterioration (favouring placebo) −0.4 (95% confidence interval [CI] −6.4 to 5.5), adjusted for baseline value (p = 0.9). For neuropsychiatric symptoms, there was no significant difference between the continue treatment and placebo groups (n = 56 and 53, respectively) in the estimated mean change in NPI scores between baseline and 6 mo; estimated mean difference in deterioration (favouring continue treatment) −2.4 (95% CI −8.2 to 3.5), adjusted for baseline value (p = 0.4). Both results became more pronounced at 12 mo. There was some evidence to suggest that those patients with initial NPI ≥ 15 benefited on neuropsychiatric symptoms from continuing treatment.Conclusions
For most patients with AD, withdrawal of neuroleptics had no overall detrimental effect on functional and cognitive status. Neuroleptics may have some value in the maintenance treatment of more severe neuropsychiatric symptoms, but this benefit must be weighed against the side effects of therapy.Trial registration: Cochrane Central Registry of Controlled Trials/National Research Register (#ISRCTN33368770). 相似文献6.
7.
Shi DF Bradshaw TD Chua MS Westwell AD Stevens MF 《Bioorganic & medicinal chemistry letters》2001,11(8):1093-1095
A series of sulfamate salt derivatives of the potent and selective 2-(4-aminophenyl)benzothiazole antitumour agents has been prepared and their evaluation as potential prodrugs for parenteral administration carried out. The salts were sparingly soluble under aqueous conditions (pH 4-9), and degradation to the active free amine was shown to occur under strongly acidic conditions. The salts were found to be markedly less active than their parent amines against sensitive human tumour cell lines in vitro. 相似文献
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9.
Eng-Hui Chew Amrita A. Nagle Yaochun Zhang Silvia Scarmagnani Puvithira Palaniappan Tracey D. Bradshaw Arne Holmgren Andrew D. Westwell 《Free radical biology & medicine》2010,48(1):98-111
Trans-cinnamaldehyde (CA) and its analogs 2-hydroxycinnamaldehyde and 2-benzoyloxycinnamaldehyde have been reported to possess antitumor activity. CA is also a known Nrf2 activator. In this study, a series of ortho-substituted cinnamaldehyde analogs was synthesized and screened for antiproliferative and thioredoxin reductase (TrxR)-inhibitory activities. Whereas CA was weakly cytotoxic and TrxR inhibiting, hydroxy and benzoyloxy substitutions resulted in analogs with enhanced antiproliferative activity paralleling increased potency in TrxR inactivation. A novel analog, 5-fluoro-2-hydroxycinnamaldehyde, was identified as exhibiting the strongest antitumor effect (GI50 1.6 μM in HCT 116 cells) and TrxR inhibition (IC50 7 μM, 1 h incubation with recombinant TrxR). CA and its 2-hydroxy- and 2-benzoyloxy-substituted analogs possessed dual TrxR-inhibitory and Nrf2-inducing effects, both attributed to an active Michael acceptor pharmacophore. At lethal concentrations, TrxR-inhibitory potencies correlated with the compounds' antiproliferative activities. The penultimate C-terminal selenocysteine residue was shown to be a possible target. Conversely, at sublethal concentrations, these agents induced an adaptive antioxidant response through Nrf2-mediated upregulation of phase II enzymes, including TrxR induction. We conclude from the results obtained that TrxR inactivation contributes at least partly to cinnamaldehyde cytotoxicity. These Michael acceptor molecules can potentially be exploited for use in different concentrations in chemotherapeutic and chemopreventive strategies. 相似文献
10.
Chew EH Matthews CS Zhang J McCarroll AJ Hagen T Stevens MF Westwell AD Bradshaw TD 《Biochemical and biophysical research communications》2006,346(1):242-251
Novel heteroaromatic quinols 4-(benzothiazol-2-yl)-4-hydroxycyclohexa-2,5-dienone (1) and 4-(1-benzenesulfonyl-1H-indol-2-yl)-4-hydroxycyclohexa-2,5-dienone (2) are promising novel anticancer agents. They exhibit in vitro antiproliferative activity against colon, renal, and breast carcinoma cell lines as well as in vivo antitumor activity in colon, renal, and breast tumor xenografts. Elucidation of the mechanism of antitumor action of these compounds is of great importance. We show in this study that the compounds induced apoptosis as demonstrated by caspase 3 and PARP cleavage at doses causing G(2)/M cell cycle arrest. Glutathione was found to play an important role in modulating quinol-mediated cytotoxicity. In HCT 116 cells, treatment with 1 and 2 caused a 2- to 3-fold increase in the total glutathione content, suggestive of a glutathione-mediated antioxidant response. Indeed, buthionine sulfoximine (BSO)-induced glutathione depleted cells were 6-10 times more sensitive to 1 and 2, while glutathione monoethyl ester supplementation decreased the antitumor potencies by 2-3 times. In further studies we determined other cellular proteins which bind to an immobilized quinol analog, and identified several proteins including beta-tubulin, heat shock protein 60, and peroxiredoxin 1 as potential molecular targets of quinols that may contribute to their proapoptotic and antiproliferative effects. 相似文献