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1. Raloxifene was metabolized predominantly by CYP3A4 in human liver microsomes to a pair of carbon-carbon (RD1–2) and ether (RD3–4) linked homodimers in an nicotinamide adenine dinucleotide phosphate-dependent manner. The major homodimer formed by human liver microsomes (RD3) was different from the major homodimer formed by peroxidases (RD1). 2. RD1, 3 and 4 were identified by both mass spectrometry (MS) and nuclear magnetic resonance (NMR) as symmetrical carbon-carbon (both carbon 7 from benzo[b]thiopen-6-ol) linked homodimer, asymmetrical ether (oxygen from 4-hydroxyphenyl and carbon 7 from benzo[b]thiopen-6-ol) linked homodimer and asymmetrical ether (oxygen and carbon 7 from benzo[b]thiopen-6-ol) linked homodimer, respectively. 3. The structures of the homodimers RD1, 3 and 4 provided evidence for free radical metabolism of raloxifene by predominantly CYP3A4 in human liver microsomes to oxygen-centered phenoxy radicals from 4-hydroxyphenyl and benzo[b]thiopen-6-ol moieties. Further delocalization to ortho carbon-centered radical was only observed for benzo[b]thiopen-6-ol derived phenoxy radical. [ABSTRACT FROM AUTHOR]

Two plant growth promoting Pseudomonas fluorescens isolates namely UOM SAR 14 and UOM SAR 80 most effectively induced resistance against downy mildew disease of pearl millet both under greenhouse and field conditions. Relative assessment of live cultures of P. fluorescens UOM SAR 14 and UOM SAR 80 and their lipopolysaccharides (LPS) extracted from their cell walls were evaluated for their ability to induce resistance against pearl millet downy mildew. Treatment with P. fluorescens and their LPS enhanced the seed germination and seedling vigour considerably. Although both live cultures and their LPS treatment induced resistance in pearl millet against downy mildew disease both under greenhouse and field conditions as evidenced by the significant reduction of the disease, live cultures were more effective than the LPS in level of resistance induced. Live cultures of UOM SAR 14 and UOM SAR 80 induced 66% and 57% protection while their respective LPS extracts offered 59 and 53% protection against downy mildew disease under greenhouse conditions. Similarly, under field conditions with very heavy inoculum pressure live cultures offered 75% and 70%, and their LPS offered 71% and 67% protection, respectively. In either case, the time gap required for the building up of resistance was found to be 3 days and nature of the resistance induced was systemic and durable with both live cultures and their lipopolysaccharides. It was also noticed that the live bacteria significantly varied in the degree of protection offered and so also their respective LPS. [ABSTRACT FROM AUTHOR]

Plant resistance (R) proteins belonging to nucleotide-binding site-leucine-rich repeat (NBS-LRR) family are mainly involved in recognition of effectors secreted by pathogens. Pearl millet [Pennisetum glaucum (L.) R.Br] is one of the most drought tolerant cereals, staple food crop of the semi-arid tropics but is highly susceptible to the downy mildew disease caused by oomycetous Sclerospora graminicola (Sacc) schroet. Earlier studies have identified several resistance gene analogues (RGAs) in pearl millet which may be involved in resistance against downy mildew. Of these, a clone RGPM213 was shown to have more than 60% identity with R-proteins coding for NBS-LRR-like protein kinase. The exact nature and function of the R-protein encoded by this gene was not known. In the present study, the cDNA of RGPM213 encompassing NBS-LRR region was inserted into an expression vector pRSET-A and transformed into BL21 E.coli cells. The expressed recombinant fusion protein with a His tag was purified using nickel affinity purification and it had a molecular weight of 35 kDa on SDS-PAGE. Immunoaffinity purification using antibodies raised against this recombinant R-protein identified two proteins of molecular weights 55 kDa and 66 kDa from pearl millet seedling extracts. Peptide mass fingerprinting of these proteins followed by homology search in database revealed similarity of the 55 kDa protein with a protein kinase from Brassica oleracia containing serine/ threonine kinase domain. [ABSTRACT FROM AUTHOR]

Pearl millet (Pennisetum glaucum L. Br.) is the most important crop in India and Africa. Downy mildew disease of pearl millet caused by the oomycetous fungus Sclerospora graminicola (Sacc.) Schroet., is the major biological constraint in the production of pearl millet. Plasma membrane H+-ATPase is induced in resistant pearl millet against downy mildew pathogen. Sodium orthovanadate, an inhibitor of H+-ATPase, was used in this study to understand its effect on other known defence responses in pearl millet including H+-ATPase. Results suggest that vanadate down-regulates all defence responses tested, such as H+-ATPase (53 ± 5.0%), peroxidase (36 ± 5.6%), phenylalanine ammonia lyase (43 ± 4.5%), β-1,3 glucanase (25 ± 4.2%), lytic activity (32 ± 3.0%), hypersensitive response (57 ± 4.3%) and pathogen colonisation. These data indicate that the plasma membrane H+-ATPase may be a key step in the signaling pathway leading to defence activation in pearl millet against downy mildew disease. [ABSTRACT FROM AUTHOR]

Downy mildew (Sclerospora graminicola [Sacc.] Schroet.) is a serious agricultural problem for pearl millet (Pennisetum glaucum [L.] R. Br.) grain production under field conditions. Six medicinally important plant species Azadirachta indica, Argemone mexicana, Commiphora caudata, Mentha piperita, Emblica officinalis and Viscum album were evaluated for their efficacy against pearl millet downy mildew. Seeds of pearl millet were treated with different concentrations of aqueous extract of the plants to examine their efficacy in controlling downy mildew. Among the plant extracts tested, V. album treatment was found to be more effective in enhancing seed quality parameters and also in inducing resistance against downy mildew disease. Germination and seedling vigor was improved in seeds treated with V. album extracts over control. Seeds treated with 10% concentration of V. album showed maximum protection against downy mildew disease under greenhouse and field conditions. The downy mildew disease protection varied from 44-70% with different concentrations. Leaf extract of V. album did not inhibit sporulation and zoospore release from sporangia of Sclerospora graminicola, indicating that the disease-controlling effect was attributed to induced resistance. Seed treatment with V. album extract increased pearl millet grain yield considerably. In V. album, treated pearl millet seedlings increased activities of peroxidase, and phenylalanine ammonia-lyase enzyme was detected. FTIR analysis of V. album extracts showed the presence of amides and other aromatic compounds which are antimicrobial compounds involved in plant defense. [ABSTRACT FROM AUTHOR]

Thionins (PR protein-13) are a class of Cys-rich polypeptides of about 5 kDa, and have revealed their role of the defense in pearl millet to Sclerospora graminicola. The purified 5 kDa thionins show a pI of 8.2 and have anti-mildew activity tested on S. graminicola. The high level of transcript expression of thionins in resistant compared to susceptible cultivars was observed. Immunofluorescence studies have shown intense fluorescence in epidermal regions, confirming its involvement in arresting pathogen ingress and in vascular regions, confirming its systemic translocation during interaction. Epidermal peeling of resistant cultivars showed that thionin protein was present in higher quantities at the papillar region of the cell wall in seedlings. [ABSTRACT FROM AUTHOR]

Induction of resistance to downy mildew caused by Plasmopara halstedii in sunflower was studied after treatment with β-amino butyric acid (BABA). Treatment of sunflower seeds with 50 mM BABA resulted in decreased disease severity and offered 47 and 50% protection under greenhouse and field conditions, respectively. The induction of resistance to P. halstedii by BABA was accompanied by the accumulation of various host defense related enzymes in susceptible sunflower seedlings. Enhanced activation of catalase, phenylalanine ammonia-lyase (PAL), chitinase (Pr3), peroxidase (POX), and polyphenol oxidase (PPO) was evident at 6 h, 9 h, 12 h, 12 h and 12 h post-inoculation, respectively in sunflower seedlings raised from seeds treated with BABA. Northern hybridisation analysis revealed increased levels of transcripts for five known defense-response genes, viz chalcone synthase, Pr-1a, peroxidase, β-1,3-glucanase and chitinase in these seedlings. This enhanced and early activation of defense related responses in the susceptible cultivar after treatment with BABA was comparable to that in the resistant cultivar. The results indicate that BABA-induced resistance against P. halstedii in sunflower is mediated through enhanced expression of genes for defense related proteins. [ABSTRACT FROM AUTHOR]

The osmoconditioning effect on pearl millet seeds was tested with different concentrations among which 1% showed an optimum effect. Seeds osmoprimed with mannitol for 3 h followed by overnight drying offered maximum germination of 99% and seedling vigour of 1465 followed by PEG and glycerol. All the three osmopriming agents recorded a significant increase on growth parameters like height of the plant, leaf area, number of tillers per plant. The results indicated that mannitol offered a maximum positive effect followed by PEG and glycerol. Notably, osmopriming has advanced five days of flowering and also has a positive effect on number and length of the earheads. The osmoconditioning agent increased the 1000 seed weight significantly over the untreated control. When the osmoprimed seeds were germinated and inoculated with downy mildew pathogen, the maximum protection of 61.76% was observed in mannitol treatment followed by PEG and glycerol under greenhouse conditions. Osmopriming has promoted seed germination percentage, seedling vigour index and growth parameters in pearl millet and also reduced downy mildew incidence. [ABSTRACT FROM AUTHOR]

Solvent extracts of 17 different basidiomycetes were tested for their ability to inhibit Sclerospora graminicola. Among those tested, only three basidiomycete crude extracts exhibited significant inhibition on pathogen sporulation, zoospore release and zoospore motility. In vitro, the chloroform extract of Ganoderma appalantum (3 mg mL-1) recorded a maximum sporangial inhibition of 52.5 and 82.0% zoospore release and 92.5% motility. Crude extracts of three different basidiomycete fungi were treated to pearl millet seeds and assessed for seed germination, seedling vigour and effectiveness against downy mildew disease under greenhouse conditions. None of the solvent extracts were found to be phytotoxic. Chloroform and petroleum ether extracts of G. appalantum (3 mg mL-1) proved to be the best by offering disease protection of 55.6 and 43.7%, respectively, followed by chloroform and petroleum ether extracts of Polyphorus spp., with 42.5 and 39.1% disease protection. The thin layer chromatography (TLC) spots that developed were eluted and tested for inhibition of S. graminicola zoosporangia. The partially purified compound from TLC chloroform extract of G. appalantum consistently showed good inhibitory effect against S. graminicola, which exhibited inhibition of sporangia (42.3%), zoospore release (76.7%) and zoospore motility (86.7%), compared to the chloroform control which offered only 1.9, 2.9 and 1.7% inhibition of sporangia, zoospore release and zoospore motility, respectively. The partially purified compound from petroleum ether extract of G. appalantum resulted in 38.0, 63.0 and 81.6% inhibition of sporangia, zoospore release and motility, respectively, compared to petroleum ether control. However, azoxystrobin 250 SC (2 µg mL-1) and apron 35 SD (0.015 mg mL-1) treated on sporangial suspension showed the highest inhibition of S. graminicola pathogen compared to chloroform and petroleum ether TLC fractions. [ABSTRACT FROM AUTHOR]

Induction of resistance to downy mildew caused by Plasmopara halstedii in sunflower was studied after treatment with PGPR (plant growth promoting rhizobacteria) strain INR7 (Bacillus spp). Treatment of sunflower seeds with 1×108cfu/ml of PGPR strain INR7 resulted in decreased disease severity and offered 51 and 54% protection under green house and field conditions, respectively. The induction of resistance to P. halstedii by PGPR strain INR7 was accompanied by the accumulation of various host defense-related enzymes in susceptible sunflower seedlings. Enhanced activation of catalase (CAT), phenylalanine ammonia-lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO) and chitinase (CHI) was evident at 6, 9, 12, 12 and 12h post inoculation, respectively, in sunflower seedlings raised from seeds treated with PGPR strain INR7. This enhanced and early activation of defense-related responses in the susceptible cultivar after treatment with PGPR strain INR7 was comparable to that in the resistant cultivar. The results indicate that PGPR strain INR7 induced resistance against P. halstedii in sunflower is mediated through enhanced expression of defense mechanism. [ABSTRACT FROM AUTHOR]

Detailed analysis of threshold levels of resistance in sunflower genotypes to Alternaria helianthi and its relation to peroxidase activity was carried out. Fourteen sunflower genotypes were categorized into resistant, moderately resistant, susceptible and highly susceptible groups based on field reaction on disease rating scale of 0 - 9. Sunflower genotypes MSH-59 and PF-56 were resistant with disease reaction scale of 3, PC-63, PC-64, RHA6D-1 and G-47 were moderately resistant with disease reaction scale of 5, CMS-859, PC-52, AC-48, R-265, CMS-338 and MR-1 were susceptible with a disease reaction scale of 7, Morden and CMS-62 belonged to a highly susceptible category with a disease reaction scale of 8. Time-course study of peroxidase (PO) activity was analysed in resistant (MSH-59) and susceptible (Morden) sunflower genotypes using spectrophotometry. High PO activity was recorded at 2 and 12 h post-inoculation with A. helianthi. At 2 h post-inoculation, resistant genotypes recorded 12.8 units while the susceptible genotype had 2.4 units of PO activity. At 12 h PO activity increased to 39.2 and 4.2 units in resistant and highly susceptible genotypes respectively. Treatment with antioxidant inhibitors sodium azide and sodium metabisulphite at various molar concentrations reduced the pathogen-induced as well as constitutive levels of PO activity. Pre-treatment of resistant sunflower genotypes with inhibitor followed by pathogen inoculation increased the disease reaction when compared to control. Higher PO activities were recorded in sunflower genotypes with high threshold levels of resistance and lesser in susceptible genotype. The study therefore gives strong evidence for the role of PO as an important enzyme of the central defense system against necrotrophic pathogen A. helianthi and could be used as a reliable biomarker for assessing resistance. [ABSTRACT FROM AUTHOR]

Abstract A survey of chilli fields in the state of Karnataka, India, showed the presence of bacterial wilt disease in important chilli growing regions. The disease incidence ranged from 26  –  32%. The pathogen was isolated from infected plant material and seeds. Infected plant material showed the release of milky white bacterial ooze. Burkholderia solanacearum was detected from chilli seeds by liquid assay and its identity was confirmed by biochemical tests, hypersensitive reaction and pathogenicity tests. Seed transmission of the pathogen up to 45% was observed in seeds artificially infested with the pathogen. Among different tissues of the seed, endosperm showed the presence of the pathogen. Biological seed treatment with antagonistic Pseudomonas fluorescens significantly ( p   =  0.05) improved the seed quality parameters under laboratory conditions and drastically reduced the bacterial wilt incidence under field conditions. Seed-borne nature, transmission and effect of Pseudomonas fluorescens in both the forms of pure culture and formulation on seed quality parameters and bacterial wilt incidence are discussed in the present work. [ABSTRACT FROM AUTHOR]

The inhibitory effect of 15 commercial and five experimental fungicides was assessed both in greenhouse and field experiments against Sclerospora graminicola, the causative agent of pearl millet downy mildew disease. Chemicals differed in anti-mildew activity. However, neither the pathogen nor the host plant was completely tolerant to any compounds tested. The plants depressed by fungicides in the germling stage recovered until formation of inflorescence, so this activity did not significantly influence grain yield. There was a significant correlation between antisporulant activity of compounds evaluated on detached leaf segments and their positive effect on yield performance. All compounds increased the grain yield of downy mildewed pearl millet when applied in the maximum doses tolerated by pearl millet. However, analysis of the cost-return budget showed that disease control < 30% is uneconomic. Fungicides of the acylanilide series exhibited the highest protective effect (over 95%) and andoprim, drazoxolon and efosit were also effective. [ABSTRACT FROM AUTHOR]

The Coffee Berry Borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae) has been a serious insect pest of coffee cultivars C. robusta and C. catimor in India since 1991, causing 40-80% coffee bean loss. To combat this important pest, an indigenous entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin was isolated from dead and moribund coffee berry borers from the wild. The fungus was cultured on yeast extractpeptone supplemented liquid medium. The mycelial mat was harvested from 12-day old cultures and lyophilized. A suspension of the most virulent isolate (Bb2) was prepared in sterile water and used as a mycopesticide. The laboratory studies were conducted on coffee berry borers by applying conidial suspensions at a dosage rate of 1 × 10[sup 6] conidia ml[sup -1]. Pest mortality with the Bb2 isolate increased from 69.3% to 95.3% with an increase in relative humidity (RH) at 25 ± 2°C. Field experiments were conducted in a coffee plantation area in the Kodagu district of Karnataka, and the results showed that, under favourable environmental conditions (27- 29°C; 82-91% RH; 10-15 inches rainfall per year), the fungus required only eight days to colonize and kill the target pest. A maximum of 75.6% insect mortality was recorded 24 days after spraying. Large-scale field trials conducted in five plantation plots between September 1995 and September 1998 showed significant insect mortality both in C. robusta and C. catimor cultivars of coffee. The potential use of this indigenous fungal strain of B. bassiana as a mycopesticide for management of CBB in India is discussed. [ABSTRACT FROM AUTHOR]

The association of transposition of the great arteries (TGA) and anomalous pulmonary venous connection is extremely rare. Children with transposition of the great arteries improved dramatically with the advent of the atrial repair. In this report, we describe a 40-day old male infant with TGA and associated anomalous pulmonary venous connection who presented with the history of cyanosis and hurried breathing. This patient underwent successful balloon atrial septostomy and discharged with uneventful recovery. [ABSTRACT FROM PUBLISHER]