We have developed a novel cost-effective procedure, namely 'chemical nanoprinting', for oligonucl... more We have developed a novel cost-effective procedure, namely 'chemical nanoprinting', for oligonucleotide or cDNA chips manufacture. In this thermo-controlled process, the oligonucleotides, covalently attached to a highly loaded 'master-chip' through disulfide bonds, are chemically transferred to the acrylamide layer mounted on a 'print-chip'. It is demonstrated here that multiple identical print-chips can be produced from a single master-chip. This duplication process is a few hundreds of times faster than any existing methods and the speed of process and cost incurred are independent of the scale of the DNA chips.
Branched nucleic acid strands exist as intermediates in certain biological reactions, and bifurca... more Branched nucleic acid strands exist as intermediates in certain biological reactions, and bifurcating DNA also presents interesting opportunities in biotechnological applications. We describe here how T4 DNA ligase can be used for ef®cient construction of DNA molecules having one 5¢ end but two distinct 3¢ ends that extend from the 2¢ and 3¢ carbons, respectively, of an internal nucleotide. The nature of the reaction products is investigated, and optimal reaction conditions are reported for the construction of branched oligonucleotides. We discuss the utility of these branched DNA nanostructures for gene detection.
A pseudo-line source has been realized by using an accelerator based DT point neutron source. The... more A pseudo-line source has been realized by using an accelerator based DT point neutron source. The pseudo-line source is obtained by time averaging of continuously moving point source or by superposition of finely distributed point sources. The line source ...
Page 1. Kinetic modelling of the active transport of copper(II) across liquid membranes usingthio... more Page 1. Kinetic modelling of the active transport of copper(II) across liquid membranes usingthiourea derivatives immobilized on microporous hydrophobic supports Fatima Z. El Aamrani, Anil Kumar¤ and Ana M. Sastre* Department of Chemical Engineering, Universitat ...
Preclinical studies have shown that stress and glucocorticoids increase mesolimbic dopamine (DA) ... more Preclinical studies have shown that stress and glucocorticoids increase mesolimbic dopamine (DA) and thereby facilitate psychostimulant self-administration. The relationship between stress-induced cortisol and mesolimbic DA responses to psychostimulants has not been studied in humans. To test the hypotheses that glucocorticoid responses to psychological stress are correlated with DA and subjective responses to psychostimulants in humans, 25 healthy adults (18-29 years) completed the Trier Social Stress Test (TSST) and two positron emission tomography (PET) scans with high-specific [ 11 C]raclopride. The first scan was preceded by intravenous saline and the second by amphetamine (AMPH). Findings showed that stress-induced cortisol levels were positively associated with AMPH-induced DA release in the ventral striatum and other striatal regions. Subjects with higher cortisol responses to stress also reported more positive subjective drug effects with AMPH than subjects with lower responses. The results are consistent with preclinical findings showing an interrelationship between glucocorticoids and mesolimbic DA dynamics, which may influence psychostimulant self-administration in humans.
In all, 19 research subjects, with current histories of frequent cocaine use, were exposed to coc... more In all, 19 research subjects, with current histories of frequent cocaine use, were exposed to cocaine-related cues to elicit drug craving. We measured the change of occupancy of dopamine at D2-like receptors with positron emission tomography (PET) and inferred a change of intrasynaptic dopamine (endogenous dopamine release), based on the displacement of radiotracer [(11)C]raclopride. Receptor occupancy by dopamine increased significantly in putamen of participants who reported cue-elicited craving compared to those who did not. Further, the intensity of craving was positively correlated with the increase in dopamine receptor occupancy in the putamen. These results provide direct evidence that occupancy of dopamine receptors in human dorsal striatum increased in proportion to subjective craving, presumably because of increased release of intrasynaptic dopamine.
Tuberous sclerosis complex (TSC) is an autosomal dominant multi-system disorder with two known di... more Tuberous sclerosis complex (TSC) is an autosomal dominant multi-system disorder with two known disease loci on chromosomes 9q34 (TSC1) and 16p13.3 (TSC2). TSC has a prevalence of approximately 1 in 5,000-6,000, exhibits incomplete penetrance, and occurs in all racial groups. Our laboratory has undertaken the complete mutation analysis of the TSC2 gene in 42 TSC families using single-strand conformation polymorphism analysis and reverse transcription-polymerase chain reaction. Of the total of 42 families, 16 show evidence of linkage to the chromosome 16 TSC2 locus and 26 are either sporadic or too small to establish chromosome linkage. The TSC2 gene spans at least 45 kilobases of genomic DNA, has 41 known exons, and codes for a 5,474-base pair transcript. After complete gene analysis, 16 TSC2 mutations have been identified, including DNA insertions, deletions, splice site mutations, and amino acid substitutions. The majority of putative TSC2 mutations were found in sporadic rather than TSC2-linked families. We have also detected 15 polymorphisms which occur in the TSC2 gene.
This study was conducted to evaluate the safety and efficacy of tacrolimus (TAC) in children with... more This study was conducted to evaluate the safety and efficacy of tacrolimus (TAC) in children with SRNS. The study group comprised of 22 consecutive children with steroid-resistant nephrotic syndrome (SRNS) who were studied prospectively. TAC was initiated with a dose of 0.10 mg/kg/day, and the dose was increased to attain a trough level of 5.0-10.0 g/l. These patients were treated with concomitant prednisone, which was subsequently tapered off and stopped. The primary outcome variable was the number of patients who attained a complete remission (CR) or partial remission (PR). The mean age of onset was 7.33 ± 5.9 years, and there were 20 boys and 2 girls. Of the 22 children, 9 had minimal change disease, 11 had focal segmental glomerulosclerosis and the other 2 had diffuse mesangial hypercellularity on histopathology. TAC had to be withdrawn in 3 children because of its side effects. Of the remaining 19 children who received adequate therapy and were able to achieve target levels, CR was seen in 16 (84%) children, 2 (10.5%) attained PR and 1 was nonresponsive. The mean time to achieve remission was 63.2 ± 44 days and the mean dose of TAC was 0.18 ± 0.07 mg/kg. The mean urine spot protein/creatinine ratios were significantly lower (0.33 ± 0.58 vs. 13.5 ± 21.9 mg/mg, p = 0.002) and the mean serum albumin levels were significantly higher (3.92 ± 0.35 g/dl vs. 2.39 ± 0.56 g/dl, p = 0.00005), as compared to those prior to starting TAC. The mean glomerular filtration rate values at the end of the study were similar to those prior to starting TAC (97.9 ± 21.2 ml/min/1.73m 2 vs. 96.4 ± 18.4 ml/min/1.73m 2 , p = 0.30). The mean duration of follow-up was 290 ± 126 days. This is the largest study so far on the safety and efficacy of TAC therapy in SRNS. Our results suggest that TAC is an effective therapeutic modality for SRNS, including the subgroup of children who are nonresponsive to the current therapeutic modalities like cyclophosphamide and cyclosporine.
Abstract Synthesis of 12-aryl-8, 9, 10, 12-tetrahydro-benzo [a] xanthen-11-ones was achieved by o... more Abstract Synthesis of 12-aryl-8, 9, 10, 12-tetrahydro-benzo [a] xanthen-11-ones was achieved by one-pot condensation of β-naphthol, substituted benzaldehydes, and 1, 3-dicarbonyl compounds catalyzed by Sc (OTf) 3 under microwave irradiation in excellent isolated yields. The catalyst was recycled up to four cycles with no appreciable loss in catalytic activity. The compounds were evaluated for Src kinase activity and anticancer activity. Graphical abstract
The present investigation deals with the synthesis of a N-methylated cyclotetrapeptide, hirsutide... more The present investigation deals with the synthesis of a N-methylated cyclotetrapeptide, hirsutide (2), by coupling of the dipeptide units Boc-L-phenylalanyl-L-N-methylphenylalanine-OH and L-valyl-L-N-methylphenylalanine-OMe followed by cyclization of the linear tetrapeptide fragment. The chemical structure was established on the basis of analytical as well as spectroscopic data. The newly synthesized cyclic peptide was subjected to pharmacological screening and found to be highly potent against the gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumoniae at 6 lg cm -3 . In addition, potent antihelmintic activity against the earthworms Megascoplex konkanensis and Pontoscotex corethruses at 1 and 2 mg cm -3 , and potent cytotoxic activity against Dalton's lymphoma ascites and Ehrlich's ascites carcinoma cell lines with IC 50 values of 14 and 22 lM were also observed. Studies revealed that the pentafluorophenyl ester method employing a catalytic amount of N-methylmorpholine proved to be better for cyclization of the linear tetrapeptide unit.
The variation in transposition history of different Ty1-copia group LTR retrotransposons in the s... more The variation in transposition history of different Ty1-copia group LTR retrotransposons in the species lineages of the Pisum genus has been investigated. A heterogeneous population of Ty1-copia elements was isolated by degenerate PCR and two of these (Tps12 and Tps19) were selected on the basis of their copy number and sequence conservation between closely related species for further in-depth study of their transpositional history in Pisum species. The insertional polymorphism of these elements and the previously characterised PDR1 element was studied by sequence-specific amplification polymorphism (SSAP). Each of these elements reveals a unique transpositional history within 55 diverse Pisum accessions. Phylogenetic trees based on the SSAP data show that SSAP markers for individual elements are able to resolve different species lineages within the Pisum genus. Finally, the SSAP data from all of these retrotransposon markers were combined to reveal a detailed picture of the intra and interspecies relationships within Pisum.
Retrotransposons are present in high copy number in many plant genomes. They show a considerable ... more Retrotransposons are present in high copy number in many plant genomes. They show a considerable degree of sequence heterogeneity and insertional polymorphism, both within and between species. We describe here a polymerase chain reaction (PCR)based method which exploits this polymorphism for the generation of molecular markers in barley. The method produces amplified fragments containing a Bare-1-like retrotransposon long terminal repeat (LTR) sequence at one end and a flanking host restriction site at the other. The level of polymorphism is higher than that revealed by amplified fragment length polymorphism (AFLP) in barley. Segregation data for 55 fragments, which were polymorphic in a doubled haploid barley population, were analysed alongside an existing framework of some 400 other markers. The markers showed a widespread distribution over the seven linkage groups, which is consistent with the distribution of the Bare-1 class of retrotransposons in the barley genome based on in situ hybridisation data. The potential applicability of this method to the mapping of other multicopy sequences in plants is discussed.
Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet cro... more Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet crop worldwide. A systematic search for the blast resistance gene analogs was carried out, using functional molecular markers. Three-fourths of the recognition-dependent disease resistance genes (R-genes) identified in plants encodes nucleotide binding site (NBS) leucine-rich repeat (LRR) proteins. NBS-LRR homologs have only been isolated on a limited scale from Eleusine coracana. Genomic DNA sequences sharing homology with NBS region of resistance gene analogs were isolated and characterized from resistant genotypes of finger millet using PCR based approach with primers designed from conserved regions of NBS domain. Attempts were made to identify molecular markers linked to the resistance gene and to differentiate the resistant bulk from the susceptible bulk. A total of 9 NBS-LRR and 11 EST-SSR markers generated 75.6 and 73.5% polymorphism respectively amongst 73 finger millet genotypes. NBS-5, NBS-9, NBS-3 and EST-SSR-04 markers showed a clear polymorphism which differentiated resistant genotypes from susceptible genotypes. By comparing the banding pattern of different resistant and susceptible genotypes, five DNA amplifications of NBS and EST-SSR primers (NBS-05 504, NBS-09 711 , NBS-07 688 , NBS-03 509 and EST-SSR-04 241 ) were identified as markers for the blast resistance in resistant genotypes. Principal coordinate plot and UPGMA analysis formed similar groups of the genotypes and placed most of the resistant genotypes together showing a high level of genetic relatedness and the susceptible genotypes were placed in different groups on the basis of differential disease score. Our results provided a clue for the cloning of finger millet blast resistance gene analogs which not only facilitate the process of plant breeding but also molecular characterization of blast resistance gene analogs from Eleusine coracana.
Seed development is a complex process controlled by temporal and spatial expression of many trans... more Seed development is a complex process controlled by temporal and spatial expression of many transcription factors (TF) inside the developing seed. In the present study, transcript profiles of all the 30 members of rice DofTFs from flowering to seed development stages were analyzed. It was found that 16 Dof genes besides a previously characterized Dof gene…
Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 k... more Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 kg/ha optimum nitrogen requirement respectively, to produce optimal yield, were chosen to understand their differential nitrogen responsiveness. Both the genotypes grown under increasing nitrogen inputs showed differences in seed/panicle, 1,000 seed weight, %nitrogen in the biomass and protein content in the seeds. All these parameters in PB1 were found to be in the increasing order in contrast to KN3119 which showed declined response on increasing nitrogen dose exceeding the normal dose indicating that both the genotypes respond differentially to the nitrogen inputs. Gene expression analysis of members of ammonium transporter gene family in flag leaves during active grain filling stage revealed that all the three members of OsAMT3 family genes (OsAMT1;1-3), only one member of OsAMT2 family i.e., OsAMT2;3 and the high affinity OsAMT1;1 were differentially expressed and were affected by different doses of nitrogen. In both the genotypes, both increase and decline in seed protein contents matched with the expressions levels of OsAMT1;1, OsGS1;1 and OsGS1;2 in the flag leaves during grain filling stage indicating that high nitrogen nutrition in KN3119 probably causes the repression of these genes which might be important during grain filling.
Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements require... more Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements required by plants. Development of crop varieties with high nitrogen use efficiency (NUE) is imperative for sustainable agriculture. Understanding how plant genes respond to different nitrogen conditions is essential for formulating approaches, for manipulating genes, for improving NUE. In the present study we analyzed the activity of three different enzymes involved in nitrogen assimilation viz., GS, GOGAT and GDH along with physiological parameters like chlorophyll variable yield (Fv/Fmax), photosynthesis rate and total chlorophyll content at four different growth stages of wheat plant development under different nitrogen treatments. For this study two different wheat varieties UP-2644 and Raj-4097 having high and low protein content, respectively in the grains were chosen. Gene expression profile of a Dof transcription factor (TaDof1 of wheat) was also included in the study to assess its role in nitrogen metabolism. Densitometry analysis at S 2 and S 3 stage of wheat spikes of both the wheat varieties grown at different nitrogen treatments showed that TaDof1 expression was up-regulated in low nitrogen treatment. In S 3 stage, in high protein content wheat variety UP-2644, TaDof1 expression was elevated in low and normal nitrogen treatment as compared to high nitrogen treatment. The gene expression profile of Dof 1 was found to coincide with the enzyme activities of GS, GOGAT at the S 3 stage. The activities of these enzymes were prolonged in the high protein content variety. Since, Dof transcription factor(s) have been previously reported to control the expression of genes involved nitrogen assimilation i.e., GS and GOGAT and may be the elevated expression of Dof 1 at the grain filling stage over expresses the GS and GOGAT genes thereby prolonging their activities.
Two genotypes showing differential immunity against Karnal bunt (Tilletia indica) were used to in... more Two genotypes showing differential immunity against Karnal bunt (Tilletia indica) were used to investigate the role of three members of cystatin gene family in growth stage dependent immunity in wheat (Triticum aestivum L.). Three members of cystatin gene family (WC1, WC2, and WC4) were cloned and sequenced. Analysis of sequenced data showed that there was 76-99% nucleotide and protein sequence identity between different genes of the wheat cystatin. In silico amino acid sequence analysis revealed the presence of a conserved signature pattern of residues and also the functional domains were presumed to be actively involved in imparting cysteine protease inhibition capability. The semi-quantitative and quantitative levels of these members were measured by means of RT-PCR, northern blotting, western blotting, and by ELISA techniques. The members of cystatin gene family were expressed in both resistant (HD 29) and susceptible genotypes (WH 542); however, the expression level was significantly (P \ 0.001) higher in resistant compared to susceptible genotype at all the stages of wheat spikes. The patterns of expression of WC2, WC4 were similar except in the levels in S 1 and S 2 stages as it remained constant (P [ 0.05) in contrary to WC1 family whose expression gradually increased from S v to S 2 stage. According to the intensity of the detected band in RT PCR, northern blot and western blot, WC1 family seems to be expressed more than the other gene families. The immunoassay results further showed that WC1 protein was abundantly expressed in resistant genotype and high expression was observed at the S2 stage as compared to susceptible genotype (P \ 0.001) suggesting that low level of expression of WC1 in S2 stage is responsible for KB infection. The results of the present study clearly indicate the role of cystatin gene family in differential and stage dependent immunity against KB.
A model for generation-recombination (g-r) noise in FOLD MOSFETs is presented incorporating the f... more A model for generation-recombination (g-r) noise in FOLD MOSFETs is presented incorporating the field dependent mobility and the bias dependent series resistance. The g-r noise is due to the emission and capture of carriers in the space charge region in the bulk-channel junction. It is observed that noise power increases with increasing drain voltage and decreases with decreasing gate voltage. The results so obtained are compared with the experimental data. ᭧ .in (R.S. Gupta). . Variation of S vd due to g-r noise with V gs . m n0 597:3 cm 2 =V Ϫ s; N t 7:99 × 10 11 cm Ϫ3 ; h 4:459 × 10 Ϫ2 V Ϫ1 ; a 0:72 × 10 Ϫ6 cm V Ϫ1 ; b 4:9 × 10 Ϫ6 cm V Ϫ1 ; V ds 0:5 V:
An analytical model of 6H-SiC inversion channel MOSFET is developed incorporating the influence o... more An analytical model of 6H-SiC inversion channel MOSFET is developed incorporating the influence of incomplete dopant ionization. The charge sheet approach is used to evaluate the drain current, transconductance and drain conductance. Maximun transconductance of 46 mS is obtained for V 550 mV at a gate voltage of 2.3 ds V. An explicit analytical expression is also developed which relate the transconductance with interface trap density. It is observed that interface state density has an effect of lowering the transconductance. Some of the results obtained are verified with the experimental data. The interface trap density effects on other device characteristics has also been discussed.
We have developed a novel cost-effective procedure, namely 'chemical nanoprinting', for oligonucl... more We have developed a novel cost-effective procedure, namely 'chemical nanoprinting', for oligonucleotide or cDNA chips manufacture. In this thermo-controlled process, the oligonucleotides, covalently attached to a highly loaded 'master-chip' through disulfide bonds, are chemically transferred to the acrylamide layer mounted on a 'print-chip'. It is demonstrated here that multiple identical print-chips can be produced from a single master-chip. This duplication process is a few hundreds of times faster than any existing methods and the speed of process and cost incurred are independent of the scale of the DNA chips.
Branched nucleic acid strands exist as intermediates in certain biological reactions, and bifurca... more Branched nucleic acid strands exist as intermediates in certain biological reactions, and bifurcating DNA also presents interesting opportunities in biotechnological applications. We describe here how T4 DNA ligase can be used for ef®cient construction of DNA molecules having one 5¢ end but two distinct 3¢ ends that extend from the 2¢ and 3¢ carbons, respectively, of an internal nucleotide. The nature of the reaction products is investigated, and optimal reaction conditions are reported for the construction of branched oligonucleotides. We discuss the utility of these branched DNA nanostructures for gene detection.
A pseudo-line source has been realized by using an accelerator based DT point neutron source. The... more A pseudo-line source has been realized by using an accelerator based DT point neutron source. The pseudo-line source is obtained by time averaging of continuously moving point source or by superposition of finely distributed point sources. The line source ...
Page 1. Kinetic modelling of the active transport of copper(II) across liquid membranes usingthio... more Page 1. Kinetic modelling of the active transport of copper(II) across liquid membranes usingthiourea derivatives immobilized on microporous hydrophobic supports Fatima Z. El Aamrani, Anil Kumar¤ and Ana M. Sastre* Department of Chemical Engineering, Universitat ...
Preclinical studies have shown that stress and glucocorticoids increase mesolimbic dopamine (DA) ... more Preclinical studies have shown that stress and glucocorticoids increase mesolimbic dopamine (DA) and thereby facilitate psychostimulant self-administration. The relationship between stress-induced cortisol and mesolimbic DA responses to psychostimulants has not been studied in humans. To test the hypotheses that glucocorticoid responses to psychological stress are correlated with DA and subjective responses to psychostimulants in humans, 25 healthy adults (18-29 years) completed the Trier Social Stress Test (TSST) and two positron emission tomography (PET) scans with high-specific [ 11 C]raclopride. The first scan was preceded by intravenous saline and the second by amphetamine (AMPH). Findings showed that stress-induced cortisol levels were positively associated with AMPH-induced DA release in the ventral striatum and other striatal regions. Subjects with higher cortisol responses to stress also reported more positive subjective drug effects with AMPH than subjects with lower responses. The results are consistent with preclinical findings showing an interrelationship between glucocorticoids and mesolimbic DA dynamics, which may influence psychostimulant self-administration in humans.
In all, 19 research subjects, with current histories of frequent cocaine use, were exposed to coc... more In all, 19 research subjects, with current histories of frequent cocaine use, were exposed to cocaine-related cues to elicit drug craving. We measured the change of occupancy of dopamine at D2-like receptors with positron emission tomography (PET) and inferred a change of intrasynaptic dopamine (endogenous dopamine release), based on the displacement of radiotracer [(11)C]raclopride. Receptor occupancy by dopamine increased significantly in putamen of participants who reported cue-elicited craving compared to those who did not. Further, the intensity of craving was positively correlated with the increase in dopamine receptor occupancy in the putamen. These results provide direct evidence that occupancy of dopamine receptors in human dorsal striatum increased in proportion to subjective craving, presumably because of increased release of intrasynaptic dopamine.
Tuberous sclerosis complex (TSC) is an autosomal dominant multi-system disorder with two known di... more Tuberous sclerosis complex (TSC) is an autosomal dominant multi-system disorder with two known disease loci on chromosomes 9q34 (TSC1) and 16p13.3 (TSC2). TSC has a prevalence of approximately 1 in 5,000-6,000, exhibits incomplete penetrance, and occurs in all racial groups. Our laboratory has undertaken the complete mutation analysis of the TSC2 gene in 42 TSC families using single-strand conformation polymorphism analysis and reverse transcription-polymerase chain reaction. Of the total of 42 families, 16 show evidence of linkage to the chromosome 16 TSC2 locus and 26 are either sporadic or too small to establish chromosome linkage. The TSC2 gene spans at least 45 kilobases of genomic DNA, has 41 known exons, and codes for a 5,474-base pair transcript. After complete gene analysis, 16 TSC2 mutations have been identified, including DNA insertions, deletions, splice site mutations, and amino acid substitutions. The majority of putative TSC2 mutations were found in sporadic rather than TSC2-linked families. We have also detected 15 polymorphisms which occur in the TSC2 gene.
This study was conducted to evaluate the safety and efficacy of tacrolimus (TAC) in children with... more This study was conducted to evaluate the safety and efficacy of tacrolimus (TAC) in children with SRNS. The study group comprised of 22 consecutive children with steroid-resistant nephrotic syndrome (SRNS) who were studied prospectively. TAC was initiated with a dose of 0.10 mg/kg/day, and the dose was increased to attain a trough level of 5.0-10.0 g/l. These patients were treated with concomitant prednisone, which was subsequently tapered off and stopped. The primary outcome variable was the number of patients who attained a complete remission (CR) or partial remission (PR). The mean age of onset was 7.33 ± 5.9 years, and there were 20 boys and 2 girls. Of the 22 children, 9 had minimal change disease, 11 had focal segmental glomerulosclerosis and the other 2 had diffuse mesangial hypercellularity on histopathology. TAC had to be withdrawn in 3 children because of its side effects. Of the remaining 19 children who received adequate therapy and were able to achieve target levels, CR was seen in 16 (84%) children, 2 (10.5%) attained PR and 1 was nonresponsive. The mean time to achieve remission was 63.2 ± 44 days and the mean dose of TAC was 0.18 ± 0.07 mg/kg. The mean urine spot protein/creatinine ratios were significantly lower (0.33 ± 0.58 vs. 13.5 ± 21.9 mg/mg, p = 0.002) and the mean serum albumin levels were significantly higher (3.92 ± 0.35 g/dl vs. 2.39 ± 0.56 g/dl, p = 0.00005), as compared to those prior to starting TAC. The mean glomerular filtration rate values at the end of the study were similar to those prior to starting TAC (97.9 ± 21.2 ml/min/1.73m 2 vs. 96.4 ± 18.4 ml/min/1.73m 2 , p = 0.30). The mean duration of follow-up was 290 ± 126 days. This is the largest study so far on the safety and efficacy of TAC therapy in SRNS. Our results suggest that TAC is an effective therapeutic modality for SRNS, including the subgroup of children who are nonresponsive to the current therapeutic modalities like cyclophosphamide and cyclosporine.
Abstract Synthesis of 12-aryl-8, 9, 10, 12-tetrahydro-benzo [a] xanthen-11-ones was achieved by o... more Abstract Synthesis of 12-aryl-8, 9, 10, 12-tetrahydro-benzo [a] xanthen-11-ones was achieved by one-pot condensation of β-naphthol, substituted benzaldehydes, and 1, 3-dicarbonyl compounds catalyzed by Sc (OTf) 3 under microwave irradiation in excellent isolated yields. The catalyst was recycled up to four cycles with no appreciable loss in catalytic activity. The compounds were evaluated for Src kinase activity and anticancer activity. Graphical abstract
The present investigation deals with the synthesis of a N-methylated cyclotetrapeptide, hirsutide... more The present investigation deals with the synthesis of a N-methylated cyclotetrapeptide, hirsutide (2), by coupling of the dipeptide units Boc-L-phenylalanyl-L-N-methylphenylalanine-OH and L-valyl-L-N-methylphenylalanine-OMe followed by cyclization of the linear tetrapeptide fragment. The chemical structure was established on the basis of analytical as well as spectroscopic data. The newly synthesized cyclic peptide was subjected to pharmacological screening and found to be highly potent against the gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumoniae at 6 lg cm -3 . In addition, potent antihelmintic activity against the earthworms Megascoplex konkanensis and Pontoscotex corethruses at 1 and 2 mg cm -3 , and potent cytotoxic activity against Dalton's lymphoma ascites and Ehrlich's ascites carcinoma cell lines with IC 50 values of 14 and 22 lM were also observed. Studies revealed that the pentafluorophenyl ester method employing a catalytic amount of N-methylmorpholine proved to be better for cyclization of the linear tetrapeptide unit.
The variation in transposition history of different Ty1-copia group LTR retrotransposons in the s... more The variation in transposition history of different Ty1-copia group LTR retrotransposons in the species lineages of the Pisum genus has been investigated. A heterogeneous population of Ty1-copia elements was isolated by degenerate PCR and two of these (Tps12 and Tps19) were selected on the basis of their copy number and sequence conservation between closely related species for further in-depth study of their transpositional history in Pisum species. The insertional polymorphism of these elements and the previously characterised PDR1 element was studied by sequence-specific amplification polymorphism (SSAP). Each of these elements reveals a unique transpositional history within 55 diverse Pisum accessions. Phylogenetic trees based on the SSAP data show that SSAP markers for individual elements are able to resolve different species lineages within the Pisum genus. Finally, the SSAP data from all of these retrotransposon markers were combined to reveal a detailed picture of the intra and interspecies relationships within Pisum.
Retrotransposons are present in high copy number in many plant genomes. They show a considerable ... more Retrotransposons are present in high copy number in many plant genomes. They show a considerable degree of sequence heterogeneity and insertional polymorphism, both within and between species. We describe here a polymerase chain reaction (PCR)based method which exploits this polymorphism for the generation of molecular markers in barley. The method produces amplified fragments containing a Bare-1-like retrotransposon long terminal repeat (LTR) sequence at one end and a flanking host restriction site at the other. The level of polymorphism is higher than that revealed by amplified fragment length polymorphism (AFLP) in barley. Segregation data for 55 fragments, which were polymorphic in a doubled haploid barley population, were analysed alongside an existing framework of some 400 other markers. The markers showed a widespread distribution over the seven linkage groups, which is consistent with the distribution of the Bare-1 class of retrotransposons in the barley genome based on in situ hybridisation data. The potential applicability of this method to the mapping of other multicopy sequences in plants is discussed.
Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet cro... more Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet crop worldwide. A systematic search for the blast resistance gene analogs was carried out, using functional molecular markers. Three-fourths of the recognition-dependent disease resistance genes (R-genes) identified in plants encodes nucleotide binding site (NBS) leucine-rich repeat (LRR) proteins. NBS-LRR homologs have only been isolated on a limited scale from Eleusine coracana. Genomic DNA sequences sharing homology with NBS region of resistance gene analogs were isolated and characterized from resistant genotypes of finger millet using PCR based approach with primers designed from conserved regions of NBS domain. Attempts were made to identify molecular markers linked to the resistance gene and to differentiate the resistant bulk from the susceptible bulk. A total of 9 NBS-LRR and 11 EST-SSR markers generated 75.6 and 73.5% polymorphism respectively amongst 73 finger millet genotypes. NBS-5, NBS-9, NBS-3 and EST-SSR-04 markers showed a clear polymorphism which differentiated resistant genotypes from susceptible genotypes. By comparing the banding pattern of different resistant and susceptible genotypes, five DNA amplifications of NBS and EST-SSR primers (NBS-05 504, NBS-09 711 , NBS-07 688 , NBS-03 509 and EST-SSR-04 241 ) were identified as markers for the blast resistance in resistant genotypes. Principal coordinate plot and UPGMA analysis formed similar groups of the genotypes and placed most of the resistant genotypes together showing a high level of genetic relatedness and the susceptible genotypes were placed in different groups on the basis of differential disease score. Our results provided a clue for the cloning of finger millet blast resistance gene analogs which not only facilitate the process of plant breeding but also molecular characterization of blast resistance gene analogs from Eleusine coracana.
Seed development is a complex process controlled by temporal and spatial expression of many trans... more Seed development is a complex process controlled by temporal and spatial expression of many transcription factors (TF) inside the developing seed. In the present study, transcript profiles of all the 30 members of rice DofTFs from flowering to seed development stages were analyzed. It was found that 16 Dof genes besides a previously characterized Dof gene…
Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 k... more Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 kg/ha optimum nitrogen requirement respectively, to produce optimal yield, were chosen to understand their differential nitrogen responsiveness. Both the genotypes grown under increasing nitrogen inputs showed differences in seed/panicle, 1,000 seed weight, %nitrogen in the biomass and protein content in the seeds. All these parameters in PB1 were found to be in the increasing order in contrast to KN3119 which showed declined response on increasing nitrogen dose exceeding the normal dose indicating that both the genotypes respond differentially to the nitrogen inputs. Gene expression analysis of members of ammonium transporter gene family in flag leaves during active grain filling stage revealed that all the three members of OsAMT3 family genes (OsAMT1;1-3), only one member of OsAMT2 family i.e., OsAMT2;3 and the high affinity OsAMT1;1 were differentially expressed and were affected by different doses of nitrogen. In both the genotypes, both increase and decline in seed protein contents matched with the expressions levels of OsAMT1;1, OsGS1;1 and OsGS1;2 in the flag leaves during grain filling stage indicating that high nitrogen nutrition in KN3119 probably causes the repression of these genes which might be important during grain filling.
Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements require... more Nitrogen is a crucial macronutrient needed in the greatest amount of all mineral elements required by plants. Development of crop varieties with high nitrogen use efficiency (NUE) is imperative for sustainable agriculture. Understanding how plant genes respond to different nitrogen conditions is essential for formulating approaches, for manipulating genes, for improving NUE. In the present study we analyzed the activity of three different enzymes involved in nitrogen assimilation viz., GS, GOGAT and GDH along with physiological parameters like chlorophyll variable yield (Fv/Fmax), photosynthesis rate and total chlorophyll content at four different growth stages of wheat plant development under different nitrogen treatments. For this study two different wheat varieties UP-2644 and Raj-4097 having high and low protein content, respectively in the grains were chosen. Gene expression profile of a Dof transcription factor (TaDof1 of wheat) was also included in the study to assess its role in nitrogen metabolism. Densitometry analysis at S 2 and S 3 stage of wheat spikes of both the wheat varieties grown at different nitrogen treatments showed that TaDof1 expression was up-regulated in low nitrogen treatment. In S 3 stage, in high protein content wheat variety UP-2644, TaDof1 expression was elevated in low and normal nitrogen treatment as compared to high nitrogen treatment. The gene expression profile of Dof 1 was found to coincide with the enzyme activities of GS, GOGAT at the S 3 stage. The activities of these enzymes were prolonged in the high protein content variety. Since, Dof transcription factor(s) have been previously reported to control the expression of genes involved nitrogen assimilation i.e., GS and GOGAT and may be the elevated expression of Dof 1 at the grain filling stage over expresses the GS and GOGAT genes thereby prolonging their activities.
Two genotypes showing differential immunity against Karnal bunt (Tilletia indica) were used to in... more Two genotypes showing differential immunity against Karnal bunt (Tilletia indica) were used to investigate the role of three members of cystatin gene family in growth stage dependent immunity in wheat (Triticum aestivum L.). Three members of cystatin gene family (WC1, WC2, and WC4) were cloned and sequenced. Analysis of sequenced data showed that there was 76-99% nucleotide and protein sequence identity between different genes of the wheat cystatin. In silico amino acid sequence analysis revealed the presence of a conserved signature pattern of residues and also the functional domains were presumed to be actively involved in imparting cysteine protease inhibition capability. The semi-quantitative and quantitative levels of these members were measured by means of RT-PCR, northern blotting, western blotting, and by ELISA techniques. The members of cystatin gene family were expressed in both resistant (HD 29) and susceptible genotypes (WH 542); however, the expression level was significantly (P \ 0.001) higher in resistant compared to susceptible genotype at all the stages of wheat spikes. The patterns of expression of WC2, WC4 were similar except in the levels in S 1 and S 2 stages as it remained constant (P [ 0.05) in contrary to WC1 family whose expression gradually increased from S v to S 2 stage. According to the intensity of the detected band in RT PCR, northern blot and western blot, WC1 family seems to be expressed more than the other gene families. The immunoassay results further showed that WC1 protein was abundantly expressed in resistant genotype and high expression was observed at the S2 stage as compared to susceptible genotype (P \ 0.001) suggesting that low level of expression of WC1 in S2 stage is responsible for KB infection. The results of the present study clearly indicate the role of cystatin gene family in differential and stage dependent immunity against KB.
A model for generation-recombination (g-r) noise in FOLD MOSFETs is presented incorporating the f... more A model for generation-recombination (g-r) noise in FOLD MOSFETs is presented incorporating the field dependent mobility and the bias dependent series resistance. The g-r noise is due to the emission and capture of carriers in the space charge region in the bulk-channel junction. It is observed that noise power increases with increasing drain voltage and decreases with decreasing gate voltage. The results so obtained are compared with the experimental data. ᭧ .in (R.S. Gupta). . Variation of S vd due to g-r noise with V gs . m n0 597:3 cm 2 =V Ϫ s; N t 7:99 × 10 11 cm Ϫ3 ; h 4:459 × 10 Ϫ2 V Ϫ1 ; a 0:72 × 10 Ϫ6 cm V Ϫ1 ; b 4:9 × 10 Ϫ6 cm V Ϫ1 ; V ds 0:5 V:
An analytical model of 6H-SiC inversion channel MOSFET is developed incorporating the influence o... more An analytical model of 6H-SiC inversion channel MOSFET is developed incorporating the influence of incomplete dopant ionization. The charge sheet approach is used to evaluate the drain current, transconductance and drain conductance. Maximun transconductance of 46 mS is obtained for V 550 mV at a gate voltage of 2.3 ds V. An explicit analytical expression is also developed which relate the transconductance with interface trap density. It is observed that interface state density has an effect of lowering the transconductance. Some of the results obtained are verified with the experimental data. The interface trap density effects on other device characteristics has also been discussed.
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Papers by ANIL KUMAR H V