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71.
Downy mildew (Peronospora plantaginis) caused two different types of infection in the floral parts of isabgol (Plantago ovata). Systemic infection resulted in long spikes bearing weak and sterile florets, which later turned black due to saprophytic
growth. Localised infection produced various symptoms ranging between normal flower opening and failure to bloom. Different
parts of infected flowers such as sepal, petal, filament and anther were reduced in size compared to healthy flowers. However,
gynoecium was elongated in localised infection. P. plantaginis induced gradual sterility of isabgol flowers. Androecium was affected more than the gynoecium was. Pollen number, pollen
viability and germination reduced drastically due to localised infection. On the contrary, there were no significant differences
between healthy and locally infected flowers in terms of stigma receptivity. In systemically infected spikes, bud development
was arrested leading to sterility. When localised disease severity was high, secondary systemic infection caused similar symptoms.
Microscopic observations showed presence of the pathogen in different parts of the flowers. Downy mildew adversely affected
seed yield and quality; producing seeds, which were smaller and lighter than the healthy ones and later, became black. Seed
yield was reduced by as much as 73.45 percent. Husk content per unit seed mass increased relatively as the total surface area
of infected seeds increased. 相似文献
72.
73.
Kaufmann T Tai L Ekert PG Huang DC Norris F Lindemann RK Johnstone RW Dixit VM Strasser A 《Cell》2007,129(2):423-433
Bid, a caspase-activated proapoptotic BH3-only protein, is essential for Fas-induced hepatocyte destruction. Recent studies published in Cell produced conflicting results, indicating that loss of Bid either protects or enhances apoptosis induced by DNA damage or replicative stress. To resolve this controversy, we generated novel Bid-deficient mice on an inbred C57BL/6 background and removed the drug-selection cassette from the targeted locus. Nine distinct cell types from these Bid-deficient mice underwent cell-cycle arrest and apoptosis in a manner indistinguishable from control WT cells in response to DNA damage or replicative stress. Moreover, we found that even cells from the original Bid-deficient mice responded normally to these stimuli, indicating that differences in genetic background or the presence of a strong promoter within the targeted locus are unlikely to explain the differences between our results and those reported previously. We conclude that Bid has no role in DNA damage- or replicative stress-induced apoptosis or cell-cycle arrest. 相似文献
74.
Gupta A Chattopadhyay I Dey S Nasipuri P Das SK Gangopadhyay PK Ray K 《Cellular and molecular neurobiology》2007,27(8):1023-1033
Aims We aim to identify the molecular defects in the ATP7B, the causal gene for Wilson disease (WD), in eastern Indian patients and attempt to assess the overall mutation spectrum
in India for detection of mutant allele for diagnostic purposes. Methods Patients from 109 unrelated families and their first-degree relatives comprising 400 individuals were enrolled in this study
as part of an ongoing project. Genomic DNA was prepared from the peripheral blood of Indian WD patients. PCR was done to amplify
the exons and flanking regions of the WD gene followed by sequencing, to identify the nucleotide variants. Results In addition to previous reports, we recently identified eight mutations including three novel (c.3412 + 1G > A, c.1771 G > A,
c.3091 A > G) variants, and identified patients with variable phenotype despite similar mutation background suggesting potential
role of modifier locus. Conclusions So far we have identified 17 mutations in eastern India including five common mutations that account for 44% of patients.
Comparative study on WD mutations between different regions of India suggests high genetic heterogeneity and the absence of
a single or a limited number of common founder mutations. Genotype–phenotype correlation revealed that no particular phenotype
could be assigned to a particular mutation and even same set of mutations in different patients showed different phenotypes. 相似文献
75.
The problem of predicting the enzymes and non-enzymes from the protein sequence information is still an open problem in bioinformatics. It is further becoming more important as the number of sequenced information grows exponentially over time. We describe a novel approach for predicting the enzymes and non-enzymes from its amino-acid sequence using artificial neural network (ANN). Using 61 sequence derived features alone we have been able to achieve 79 percent correct prediction of enzymes/non-enzymes (in the set of 660 proteins). For the complete set of 61 parameters using 5-fold cross-validated classification, ANN model reveal a superior model (accuracy = 78.79 plus or minus 6.86 percent, Q(pred) = 74.734 plus or minus 17.08 percent, sensitivity = 84.48 plus or minus 6.73 percent, specificity = 77.13 plus or minus 13.39 percent). The second module of ANN is based on PSSM matrix. Using the same 5-fold cross-validation set, this ANN model predicts enzymes/non-enzymes with more accuracy (accuracy = 80.37 plus or minus 6.59 percent, Q(pred) = 67.466 plus or minus 12.41 percent, sensitivity = 0.9070 plus or minus 3.37 percent, specificity = 74.66 plus or minus 7.17 percent). 相似文献
76.
77.
Raman Dhariwal Vijay Gahlaut Bhaganagare R. Govindraj Dharmendra Singh Saloni Mathur Shailendra Vyas Rajib Bandopadhyay Jitendra Paul Khurana Akhilesh Kumar Tyagi Kumble Vinod Prabhu Kunal Mukhopadhyay Harindra Singh Balyan Pushpendra Kumar Gupta 《Functional & integrative genomics》2015,15(2):233-245
78.
Vikas SharmaJente Boonen Nagendra S. ChauhanMayank Thakur Bart De SpiegeleerV.K. Dixit 《Phytomedicine》2011,18(13):1161-1169
According to Indian Systems of Medicine, Spilanthes acmella (L.) Murr. (Family - Asteraceae), is considered effective in the treatment of sexual deficiencies especially due to ageing. In the present study, characterization of ethanolic extracts of the Spilanthes acmella flower and its effect on general mating pattern, penile erection and serum hormone levels of normal male Wistar albino rats were investigated and compared with sildenafil citrate. In vitro nitric oxide release was also investigated in human corpus cavernosum cell line. As N-alkylamides are a promising group, their profiling was performed using a gradient reversed phase high performance liquid chromatography/electrospray ionization ion trap mass spectrometry (HPLC/ESI-MS) method on an embedded polar column. MS1 and MS2 fragmentation data were used for identification purposes. For assessment of sexual behavior, animals were divided into five groups of eight male rats. The extracts (50, 100 and 150 mg/kg body weight/day) and sildenafil citrate (5 mg/kg body weight/day) (positive control) were administered orally for 28 days. The behavioral and sexual parameters were observed at days 0, 15, 28 and after a lapse of 7 and 14 days of discontinuance of drug treatment. Five N-isobutylamides, one 2-methylbutylamide and one 2-phenylethylamide were identified. The orally administered extract had a dose dependent positive effect on mounting frequency, intromission frequency and ejaculation frequency and the most significant effects (p < 0.05) were observed at 150 mg/kg treatment, even after a lapse of 7 and 14 days of discontinuance of drug treatment. A dose dependent effect was also observed on the FSH, LH and testosterone serum levels. With 150 mg/kg of ethanolic extract the values for FSH, LH and testosterone were 3.10 ± 0.25 mlU/ml, 6.87 ± 0.18 mlU/ml and 3.72 ± 0.12 ng/ml, respectively. In vitro nitric oxide release was 21.7 ± 2.9 μM, which was significantly higher compared to the control group (p < 0.01). Sildenafil citrate exhibited also a significant effect on NO release, but no effect on hormone levels of rats was observed. The aphrodisiac potential of an ethanolic Spilanthes acmella extract was demonstrated in vitro and in vivo. N-Alkylamides might attribute to the improved sexual potential. Study lends support to the traditional utilization of S. acmella as a sexual stimulating agent. 相似文献
79.
Matts RL Brandt GE Lu Y Dixit A Mollapour M Wang S Donnelly AC Neckers L Verkhivker G Blagg BS 《Bioorganic & medicinal chemistry》2011,19(1):684-692
Several Hsp90 modulators have been identified including the N-terminal ligand geldanamycin (GDA), the C-terminal ligand novobiocin (NB), and the co-chaperone disruptor celastrol. Other Hsp90 modulators elicit a mechanism of action that remains unknown. For example, the natural product gedunin and the synthetic anti-spermatogenic agent H2-gamendazole, recently identified Hsp90 modulators, manifest biological activity through undefined mechanisms. Herein, we report a series of biochemical techniques used to classify such modulators into identifiable categories. Such studies provided evidence that gedunin and H2-gamendazole both modulate Hsp90 via a mechanism similar to celastrol, and unlike NB or GDA. 相似文献
80.
Nepali K Agarwal A Sapra S Mittal V Kumar R Banerjee UC Gupta MK Satti NK Suri OP Dhar KL 《Bioorganic & medicinal chemistry》2011,19(18):5569-5576
A series of forty two N-(1,3-diaryl-3-oxopropyl)amides were synthesized via an efficient, modified Dakin-West reaction and were evaluated for in vitro xanthine oxidase inhibitory activity for the first time. Structure-activity relationship analyses have been presented. Selected active xanthine oxidase inhibitors (3r, 3s, and 3zh) were assessed in vivo to study their anti-hyperuricemic effect in potassium oxonate induced hyperuricemic mice model. Compound 3s emerged as the most potent xanthine oxidase inhibitor (IC(50)=2.45 μM) as well as the most potent anti-hyperuricemic agent. The basis of significant inhibition of xanthine oxidase by 3s was rationalized by its molecular docking into catalytic site of xanthine oxidase. 相似文献