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11.
The effect of biotic elicitors (yeast extract, chitosan), signaling molecule (salicylic acid), and polyamines (putrescine and spermidine) was studied with respect to isoflavones accumulation in cell suspension cultures of corylifolia L. Untreated cell suspension (control) accumulated 1.66% dry wt of daidzein and 0.165% dry wt of genistein. In precursor feeding experiment, phenylalanine at 0.5 mM concentration led to 1.3 fold higher production of daidzein (1.99% dry wt) and genistein (0.22% dry wt). In biotic elicitors, yeast extract (100 mg/L) was found to be the most efficient elicitor to induce higher production levels of daidzein (2.21% dry wt) and genistein (0.293% dry wt) in suspension cultures. Salicylic acid (signaling molecule) at 1 mM concentration stimulated the maximum accumulation of daidzein (3.4% dry wt) and genistein (0.41% dry wt) 2 days after elicitation. In case of polyamines, spermidine (100 mM) resulted in highest accumulation of daidzein (3.2% dry wt) and genistein (0.475% dry wt) after 7 days of addition, which was 2.4 fold of that in control. This is the first report on kinetics of isoflavone production in response to elicitation in cell suspension of P. corylifolia.  相似文献   
12.
The effect of biotic elicitors (yeast extract, chitosan), signaling molecule (salicylic acid), and polyamines (putrescine and spermidine) was studied with respect to isoflavones accumulation in hairy root cultures of Psoralea corylifolia L. Untreated hairy roots (control) accumulated 1.55% dry wt of daidzein and 0.19% dry wt of genistein. In precursor feeding experiment, phenylalanine at 2 mM concentration led to 1.3 fold higher production of daidzein (1.91% dry wt) and genistein (0.27% dry wt). In biotic elicitors, chitosan (2 mg/L) was found to be the most efficient elicitor to induce daidzein (2.78% dry wt) and genistein (0.279% dry wt) levels in hairy roots. Salicylic acid at 1 mM concentration stimulated the maximum accumulation of daidzein (2.2% dry wt) and genistein (0.228% dry wt) 2 days after elicitation. In case of polyamines, putrescine (50 mM) resulted in highest accumulation of daidzein (3.01% dry wt) and genistein (0.227% dry wt) after 5 days of addition. Present results indicated the effectiveness of elicitation and precursor feeding on isoflavones accumulation in hairy roots of P. corylifolia. This is the first report of elicitation on isoflavones production by hairy roots of P. corylifolia.  相似文献   
13.
Multivariate analysis of codon and amino acid usage was performed for three Leishmania species, including L. donovani, L. infantum and L. major. It was revealed that all three species are under mutational bias and translational selection. Lower GC 12 and higher GC 3S in all three parasites suggests that the ancestral highly expressed genes (HEGs), compared to lowly expressed genes (LEGs), might have been rich in AT-content. This also suggests that there must have been a faster rate of evolution under GC-bias in LEGs. It was observed from the estimation of synonymous/non-synonymous substitutions in HEGs that the HEG dataset of L. donovani is much closer to L. major evolutionarily. This is also supported by the higher d N value as compared to d S between L. donovani and L. major, suggesting the conservation of synonymous codon positions between these two species and the role of translational selection in shaping the composition of protein-coding genes.  相似文献   
14.
A series of novel N-(3-aryl-1,2,4-triazol-5-yl) cinnamamide derivatives were designed on basis of structural similarity to the known FAS II inhibitors. Topliss operational method was used to optimize the potency of molecules. The minimum inhibitory concentration (MIC) of all synthesized compounds was determined against Mycobacterium tuberculosis H(37)R(v) using resazurin microtitre assay (REMA) plate method. The synthesized compounds exhibit antimycobacterial activity in the range of 5-95μM with a good safety profile.  相似文献   
15.
16.

Background

Cystic fibrosis transmembrane conductance regulator (CFTR) gene accounts for an autosomal recessive condition called cystic fibrosis (CF). In the Indian subcontinent, CF and its related diseases are under-diagnosed by the medical community due to poor knowledge of the disease and its confounding diagnosis, and also due to poor medical facilities available for these patients, thus causing an increased infant mortality rate with a low life expectancy in general. The aim of the study was to document the spectrum and distribution of CFTR mutations in controls, asthma and chronic pancreatitis cases of North India.

Methods

A total of 800 subjects including 400 controls, 250 asthma cases and150 chronic pancreatitis cases were analyzed for 6 mutations (F508del, G542X, G551D, R117H, W1282X, and S549N) and IVS8 Tn polymorphism.

Results

Out of 800 subjects, 18% [asthma — 24% (n = 250), CP — 29.33% (n = 150) cases and controls — 9.3% (n = 400)] were positive for heterozygous mutation, 0.8% of the (n = 250) asthmatic cases (n = 250) were homozygous for IVS8 T5 polymorphism while no subjects were found positive for W1282X mutation. T5 polymorphism was more common in asthmatic cases while F508del mutation in chronic pancreatitis cases. The carrier frequency of F508del, G542X, G551D, R117H, S549N and T5 was 0.015, 0.025, 0.02, 0.005, 0.005, and 0.022 respectively. The cumulative carrier frequency was 0.093.

Conclusion

CFTR mutations were underestimated in Indian population. The present study will serve in establishment of genetic screening and prenatal setup for Indian population.  相似文献   
17.
The objective of this study was to investigate the sustained release of a hydrophilic drug, montelukast (MK), from two biodegradable polymeric drug delivery systems, in situ implant (ISI) and in situ microparticles (ISM). N-Methyl pyrrolidone (NMP), dimethyl sulfoxide (DMSO), triacetin, and ethyl acetate were selected as solvents. The release of 10% (w/v) MK from both systems containing poly-lactic-co-glycolic acid (PLGA) as the biodegradable polymer was compared. Upon contact with the aqueous medium, the PLGA in ISI and ISM systems solidified resulting in implants and microparticles, respectively. The in vitro drug release from the ISI system showed marked difference from miscible solvents (NMP and DMSO) than the partially miscible ones (triacetin and ethyl acetate), and the drug release decreased with increased PLGA concentration. In the ISM system, the initial in vitro drug release decreased with decreased ratio of polymer phase to external oil phase. In vivo studies in rats showed that ISM had slower drug release than the drug release from ISI. Also, the ISM system when compared to ISI system had significantly reduced initial burst effect. In vitro as well as the in vivo studies for both ISI and ISM systems showed sustained release of MK. The ISM system is suitable for sustained release of MK over 4-week period with a lower initial burst compared to the ISI system. Stability studies of the ISI and ISM formulations showed that MK is stable in the formulations stored at 4°C for more than 2 years.  相似文献   
18.

Background

There has been increasing interest in the interaction of the basal ganglia with the cerebellum and the brainstem in motor control and movement disorders. In addition, it has been suggested that these subcortical connections with the basal ganglia may help to coordinate a network of regions involved in mediating posture and stabilization. While studies in animal models support a role for this circuitry in the pathophysiology of the movement disorder dystonia, thus far, there is only indirect evidence for this in humans with dystonia.

Methodology/Principal Findings

In the current study we investigated probabilistic diffusion tractography in DYT1-negative patients with cervical dystonia and matched healthy control subjects, with the goal of showing that patients exhibit altered microstructure in the connectivity between the pallidum and brainstem. The brainstem regions investigated included nuclei that are known to exhibit strong connections with the cerebellum. We observed large clusters of tractography differences in patients relative to healthy controls, between the pallidum and the brainstem. Tractography was decreased in the left hemisphere and increased in the right hemisphere in patients, suggesting a potential basis for the left/right white matter asymmetry we previously observed in focal dystonia patients.

Conclusions/Significance

These findings support the hypothesis that connections between the basal ganglia and brainstem play a role in the pathophysiology of dystonia.  相似文献   
19.
How viral and host factors contribute to the severe pathogenicity of the H5N1 subtype of avian influenza virus infection in humans is poorly understood. We identified three clusters of differentially expressed innate immune response genes in lungs from H5N1 (A/Vietnam/1203/04) influenza virus-infected ferrets by oligonucleotide microarray analysis. Interferon response genes were more strongly expressed in H5N1-infected ferret lungs than in lungs from ferrets infected with the less pathogenic H3N2 subtype. In particular, robust CXCL10 gene expression in H5N1-infected ferrets led us to test the pathogenic role of signaling via CXCL10's cognate receptor, CXCR3, during H5N1 influenza virus infection. Treatment of H5N1-infected ferrets with the drug AMG487, a CXCR3 antagonist, resulted in a reduction of symptom severity and delayed mortality compared to vehicle treatment. We contend that unregulated host interferon responses are at least partially responsible for the severity of H5N1 infection and provide evidence that attenuating the CXCR3 signaling pathway improves the clinical course of H5N1 infection in ferrets.  相似文献   
20.
Agarwood is a valuable oleoresin obtained from wounded tree of various genus of Thymelaeaceae family especially from Aquilaria species. Agarwood is regarded as most treasured non-timber forest product used in fragrances as well as medicines. Quality of agarwood plays an important role to define its commercial value. Different countries use different grading pattern to define the quality of agarwood. More than 250 compounds have been identified so far, mostly sesquiterpenoids, chromones and volatile aromatic compounds. GC–MS is the considered as a best method for the identification of chemical profile of the agarwood by various authors. Present review discusses the various methods used to determine quality of agarwood and chemical constituents of infected agarwood tree.  相似文献   
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