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61.
T. Sreelatha A. Hymavathi J. Madhusudhana Murthy P.U. Rani J. Madhusudana Rao K. Suresh Babu 《Bioorganic & medicinal chemistry letters》2010,20(9):2974-2977
A bioassay-guided fractionation and chemical examination of chloroform extract of Plumbago capensis roots resulted in isolation and characterization of two new napthaquinone derivatives (4, 8) along with six known compounds (1–3, 5–7). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 1D and 2D NMR) data analysis and by comparison with the literature data. All the compounds were tested for their mosquito larvicidal activity against fourth instar larvae of Aedes aegypti, and compared with that of rotenone. Among the tested compounds, isoshinanolone (3) and plumbagin (1) showed excellent toxicity with LC50 values of 1.26 and 5.43 μg/mL. New compound (8) displayed moderate toxicity against the tested mosquito species. 相似文献
62.
Deepa Selvi Rani Perundurai S. Dhandapany Pratibha Nallari Periyasamy Govindaraj Lalji Singh Kumarasamy Thangaraj 《Mitochondrion》2010,10(2):166-173
Mutations in PTPN11 gene was responsible for ~50% of the Noonan syndrome (NS), however, we did not find any mutation in PTPN11 in any of seven NS patients analysed. Whereas, the complete mtDNA sequencing revealed 146 mutations, of which five, including one heteroplasmic (A11144R; Thr → Ala) non-synonymous mutation, were novel and exclusively observed in NS patients. Interestingly all the seven probands and their maternal relatives were clustered under a major haplogroup R and its novel sub-haplogroups (R7b1b, R30a1, R30c, T2b7, U9a1) exclusive in NS, therefore we strongly suggest that these haplogroups may influence NS in South Indian populations. 相似文献
63.
Dev Chandran Kolli Bhaktavatsala Reddy Shahana Pallichera Vijayan Parthasarthy Sugumar Gudavalli Sudha Rani Ponsekaran Santha Kumar Lingala Rajendra Villuppanoor Alwar Srinivasan 《Indian journal of microbiology》2010,50(3):266-274
Peste des Petits Ruminants (PPR) is a highly contagious animal disease caused by the Peste des Petits Ruminants virus (PPRV) belonging to the genus morbillivirus and family Paramyxoviridae. The disease results in high morbidity and mortality
in goats, sheep and in some small wild ruminants. The presence of large number of small ruminants reared in endemic areas
makes PPR a notorious disease threatening the livelihood of poor farmers. Conventional vaccination using a live, attenuated
vaccine gives adequate protection but cannot be used in case of eradication of the disease due to difficulty in differentiation
of infected animals from the vaccinated ones. 相似文献
64.
65.
Daizy R. Batish K. Lavanya Harminder Pal Singh Ravinder Kumar Kohli 《Plant Growth Regulation》2007,51(2):119-128
The present study was conducted to investigate the effect of the residue of Chenopodium murale L. on growth, nodulation and macromolecule content of two legume crops, viz., Cicer arietinum L. (chickpea) and Pisum sativum L. (pea). A significant reduction in root and shoot length as well as dry matter accumulation occurred when both the legumes
were grown in the soil amended with 5, 10, 20 and 40 g residue kg−1 soil. In general, a gradual decline in growth was associated with an increasing amount of residues in the soil. There was
also a significant reduction in total chlorophyll content and the amounts of protein and carbohydrates (macromolecules) in
plants growing in the residue-amended soil. The nodulation was completely absent in chickpea and pea when the plants were
grown in the soil amended with 10 and 20 g residue kg−1 soil, respectively. At a lower rate of residue amendment (5 g kg−1 soil), a significant decline in nodule number and weight, and leghaemoglobin content was recorded. Root oxidizability, an
indirect measure of tissue viability and cellular respiration, was adversely affected in both the legumes under various treatments
of residue amendment. The observed growth reduction concomitant with increased proline accumulation indicated the presence
of some inhibitory compounds in the residue-amended soil. It was rich in phenolics identified as protocatechuic, ferulic,
p-coumaric and syringic acid with 12.8, 30.4, 20.2 and 33.6% relative content, respectively. The results suggest that the residue
of C. murale releases phenolic allelochemicals, which deleteriously affect the growth, nodulation and macromolecule content of chickpea
and pea. 相似文献
66.
Hypomorphic mutations in the gene encoding a key Fanconi anemia protein, FANCD2, sustain a significant group of FA-D2 patients with severe phenotype
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Kalb R Neveling K Hoehn H Schneider H Linka Y Batish SD Hunt C Berwick M Callen E Surralles J Casado JA Bueren J Dasi A Soulier J Gluckman E Zwaan CM van Spaendonk R Pals G de Winter JP Joenje H Grompe M Auerbach AD Hanenberg H Schindler D 《American journal of human genetics》2007,80(5):895-910
FANCD2 is an evolutionarily conserved Fanconi anemia (FA) gene that plays a key role in DNA double-strand-type damage responses. Using complementation assays and immunoblotting, a consortium of American and European groups assigned 29 patients with FA from 23 families and 4 additional unrelated patients to complementation group FA-D2. This amounts to 3%-6% of FA-affected patients registered in various data sets. Malformations are frequent in FA-D2 patients, and hematological manifestations appear earlier and progress more rapidly when compared with all other patients combined (FA-non-D2) in the International Fanconi Anemia Registry. FANCD2 is flanked by two pseudogenes. Mutation analysis revealed the expected total of 66 mutated alleles, 34 of which result in aberrant splicing patterns. Many mutations are recurrent and have ethnic associations and shared allelic haplotypes. There were no biallelic null mutations; residual FANCD2 protein of both isotypes was observed in all available patient cell lines. These analyses suggest that, unlike the knockout mouse model, total absence of FANCD2 does not exist in FA-D2 patients, because of constraints on viable combinations of FANCD2 mutations. Although hypomorphic mutations arie involved, clinically, these patients have a relatively severe form of FA. 相似文献
67.
Keratinases degrade feather in presence of a suitable reducing agent. Here we have demonstrated that conventional serine and
cysteine proteases (subtilsin, chymotrypsin and papain) which selectively cleave proteins at the hydrophobic P1 residues also
degrade feathers in presence of a suitable reducing agent in the form of live cells or chemical reductants. Further, trypsin
and pepsin were also shown to degrade feather after cleaving hydrophobic residues of feathers following 2 h pre-treatment
by any of the proteases. 相似文献
68.
G. Rani 《Journal of applied phycology》2007,19(6):803-807
The aim of the present study was to detect organic substances functioning as osmoticants that are used by the intertidal alga,
Cladophora vagabunda (L.) Hoek (Chlorophyceae), to adapt to a wide range of salinity. The major constituents of the amino acid pool were aspartate,
glutamate, glycine, valine, lysine, histidine, arginine, and proline. There were concomitant increases in the acidic amino
acids: aspartate and the glutamate and the basic amino acids: lysine, histidine and arginine in response to salinity stress.
The appearance of proline at hypersalinity alone showed that it acts as an osmoticant. As salinity increased, there was a
progressive shift in the electrophoretic pattern of protein bands. New peptide bands appeared under hyposalinity (10‰) and
hypersalinity (65‰) stress conditions in addition to the usual bands which appeared in the control (35‰). Glycine betaine,
which has been considered a novel organic osmolyte in a number of organisms, has also been observed in C. vagabunda in response to salinity stress. The synthesis of the compatible solute glycine betaine and the amino acid proline with increasing
salinity illustrates the contention that marine algae establish an osmotic equilibrium primarily by the synthesis of organic
compounds.
Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines. 相似文献
69.
Mohan KN Rani BS Selvam S Debarshi S Kadandale JS 《Cytogenetic and genome research》2007,119(3-4):255-262
By using ligation-mediated PCR products from mealybug DNA as tester and biotinylated fly DNA as driver, we recovered a fraction of the tester that remains hybridized to driver following high-stringency washing conditions. This fraction is expected to contain mealybug sequences conserved in the fly (MCF). Reciprocal experiments enabled the isolation of fly sequences conserved in the mealybug (FCM). Coding sequences among MCF show amino acid identities >40% with fly proteins, allowing a reliable identification of orthologs. Three sequences from the fly cytogenetic positions 98-99 were hybridized onto mealybug chromosomes and the results identified differences in synteny between the two species. Taken together, our results present a method for direct isolation of sequences conserved between an 'orphan' (mealybug) genome and a 'reference' (fly) genome and showed that these sequences can be used to study chromosome synteny in the mealybug. 相似文献