2011

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The Basic cardiovascular responses to postural changes, exercise, and cold pressor test: Do they vary in accordance with the dual constitutional types of ayurveda?
(2011) Patwardhan, Kishor; Tripathi, Piyush Kumar; Singh, Girish
According to Ayurveda, the native Indian system of healthcare, three Doshas, namely, Vata, Pitta, and Kapha, are the basic mutually reciprocal mechanisms that are responsible for the maintenance of homeostasis in human beings. Ayurveda classifies entire human population into seven constitutional types (Prakriti), based on the dominance of any single or a combination of two or three Doshas. Considering the fact that, in the recent past there have been several studies that have proposed some important genetic, biochemical and haematological bases for Prakriti, we conducted the present study in 90 randomly selected clinically healthy volunteers belonging to dual constitutional types (Dvandvaja Prakriti) to evaluate the variability of heart rate and arterial blood pressure in response to specific postural changes, exercise, and cold pressor test. The results of this study, in general, suggest that these basic cardiovascular responses do not vary significantly as per the dual constitutional types. However, we noted a significant fall in the diastolic blood pressure immediately after performing the isotonic exercise for five minutes, in Vata-Kapha individuals in comparison to the other two groups, namely, Pitta-Kapha and Vata-Pitta.
Late presentation of fractures of the lateral condyle of the humerus in children
(2011) Khare, Ghanshyam K.; Saraf, Shyam N.
Background: The current controversy regarding the management of fractures of the lateral condyle of the humerus presenting between 3 to 12 weeks prompted us to evaluate our results of open reduction and internal fixation of such fractures. Patients and Methods: Twenty-one patients operated between March 1995 and February 2001 qualified for this study. Five patients presented between 3-4 weeks, nine between 5-8 weeks and seven between 9-12 weeks post injury. Ten fractures were classified as stage II and eleven as stage III (Jacob et al. criteria). The mean age was 8 years (range: 4-14 years). All patients underwent surgery (open reduction and internal fixation with K-wires/screw, with or without bone grafting). The results were assessed by the modified criteria of Agarwal et al. after an average follow-up of 2.3 years. Results: Excellent to good results were observed in all the five patients presenting at 3-4 weeks post injury. In the patients presenting at 5-8 weeks, the results were excellent in one, good in four, fair in three, and poor in one patient. The fracture united in all cases; however, malunion was observed in four patients. The fractures that were operated at 9-12 weeks showed good results in one case, fair result in three cases, and poor result in three cases. Avascular necrosis of the lateral condyle in one patient, premature fusion in two patients, pin tract infection in three patients, and gross restriction of elbow movements in three patients were the major complications in this group. Accurate reduction was difficult as a result of new bone formation and remodeling at the fracture surfaces. Multiple incisions over the common extensor aponeurosis and bone graft supplementation were helpful for achieving acceptable reduction. Conclusion: Open reduction and internal fixation is recommended in all cases of displaced fractures of the lateral condyle of the humerus presenting at up to 12 weeks post injury. However, the results become poorer with increase in duration after injury and the grade of displacement. To avoid complications it is important to carry out careful dissection of the soft tissue attachments and to mobilize the fragment without the use of force.
Differences in ozone sensitivity at different NPK levels of three tropical varieties of mustard (Brassica campestris L.): Photosynthetic pigments, metabolites, and antioxidants
(2011) Singh, Poonam; Agrawal, Madhoolika; Agrawal, Shashi Bhushan
The effects of ambient O3 at two different levels of nitrogen, phosphorus, and potassium, (recommended and 1.5 times the recommended NPK) on three tropical varieties of mustard (Brassica campestris L. var. Kranti, Aashirwad and Vardan) were explored to unravel the mechanism of protection under higher NPK level at a rural experimental site using open top chambers. Ambient O3 concentrations ranged from 27.7 to 59.04 ppb. Lipid peroxidation, antioxidative enzymes, and metabolites were higher, whereas photosynthetic pigments and protein were lower in all the varieties of mustard grown in non-filtered chambers than in filtered chambers. The magnitude of response varied with varieties, NPK levels and ages. Vardan showed a maximum stimulation in the antioxidative defense system, thus efficient scavenging of ROS produced by O3 and consequently conferred greater tolerance in terms of least reductions in pigments and protein as compared to Kranti and Aashirwad. The antioxidant defense system was not stimulated in response to 1.5 times the recommended NPK, but higher levels of pigments and protein were maintained compared to the recommended NPK under ambient O3 levels. © 2010 Springer Science+Business Media B.V.
Chemical reaction- and particle diffusion-based kinetic modeling of metal biosorption by a Phormidium sp.-dominated cyanobacterial mat
(2011) Kumar, Dhananjay; Gaur, J.P.
The present study explores the suitability of chemical reaction-based and diffusion-based kinetic models for defining the biosorption of Cu(II), Cd(II) and Pb(II) by Phormidium sp.-dominated mat. The time-course data of metal sorption by the test mat significantly (r2=0.932-0.999) fitted to the chemical reaction-based models namely pseudo-first-order, -second-order, and the general rate law. However, these models fail to accurately describe the kinetics of metal biosorption due either to prefixed order or unjustifiable change in rate constant and reaction order with varying concentrations of metal and biomass in the solution. The diffusion-based models, namely, the intra-particle diffusion model and the external mass transfer model fitted well to the time-course metal sorption data, thus suggesting involvement of both external and intra-particle diffusion processes in sorption of test metals by mat biomass. However, the Boyd kinetic expression clearly showed that the external mass transfer is the dominant process. © 2010 Elsevier Ltd.
Substrate induced respiration and soluble crude protein production by soil mycobiota involved in the decomposition of Sesbania aculeatal L.
(Academic Journals Inc., 2011) Kumar, Ravindra; Sinha, Asha; Srivastava, Seweta; Srivastava, Manisha
The aim of the present study was to determine the decomposition rate of Sesbania aculeata L. by CO2 evolution and to estimate Soluble Crude Protein (SCP) production by dominant decomposing mycoflora of Sesbania aculeata L. Eight dominant decomposing mycobiota were selected for the study. In the substrate induced respiration the significant difference was observed in both sterilized and unsterilized substrate with the test fungi. The maximum CO2 evolution was observed with Aspergillus niger in sterilized (16.04 μg day -1) and unsterilized green manure (18.92 μg day -1). In other experiment conducted for the estimation of soluble crude protein production Penicillium citrinum has produced maximum SCP (26.54%) at 25°C followed by Trichoderma harzianum, Aspergillus niger and Curvularia lunata whereas minimum soluble crude protein production was observed in Penicillium rubrum (8.46%) at 35°C. The maximum per cent biomass reduction observed by Aspergillus niger (28.60%) at 25°C and minimum was found in Penicillium rubrum (3.80%) at 35°C. Among seven different nitrogen sources tested against Penicillium citrinum, the highest producer of SCP, potassium nitrate was found to be the best for maximum SCP production (26.54%) whereas the least suitable nitrogen source for SCP production by Penicillium citrinum was recorded to be sodium nitrate (14.85%). © 2011 Academic Journals Inc.
Expression of key antioxidant enzymes under combined effect of heat and cadmium toxicity in growing rice seedlings
(Kluwer Academic Publishers, 2011) Nahakpam, Sareeta; Shah, Kavita
Effect of Cd2+ toxicity and heat stress in sensitive rice cv. DR-92 and tolerant rice cv. Bh-1 grown in North East region of India were studied in sand cultures. Increasing levels of 0-500 μM Cd2+ alone and/or heat stress showed increased activities of superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase and glutathione reductase enzymes which were associated with induced oxidative stress and altered enzyme activities. The values for SOD and POD activities were always more in cv. DR-92 whereas CAT and GR activities were higher in cv. Bh-1 in roots and shoots under Cd2+ or heat stress alone in sensitive cv. DR-92. Upon imposition of a combination of Cd2+ + heat the activities of SOD and POD decreased significantly in root/shoot of both the sensitive and tolerant rice varieties. A nine fold increase in GR activity under combination of heat + 100 μM Cd2+ stress in shoots of cv. Bh-1 at day 15 was noted when compared to controls. The dual stress combination of Cd2+ + heat did not alter catalase activity in vivo in both the rice varieties. Results suggest a time-specific and varietal distribution of the antioxidant enzymes in rice plants subjected to Cd2+ and/or heat stress. Tolerant cv. Bh-1 has better survival to combined stressors like Cd2+ and heat than sensitive rice cv. DR-92 and heat stress when given in combination with Cd2+ toxicity seem to mitigate the effect of Cd2+ stress alone in rice. The study indicates individual Cd2+ toxicity and heat stress and a combination of the two stresses to have separate implications on antioxidative defense mechanism in rice plants. Among enzymes of the defense apparatus ascorbate peroxidase and glutathione reductase appear to serve as an important component for better survival of rice plants under combination of Cd2+ + heat stress. © 2010 Springer Science+Business Media B.V.
Denoising by singular value decomposition and its application to electronic nose data processing
(2011) Jha, Sunil K.; Yadava, R.D.S.
This paper analyzes the role of singular value decomposition (SVD) in denoising sensor array data of electronic nose systems. It is argued that the SVD decomposition of raw data matrix distributes additive noise over orthogonal singular directions representing both the sensor and the odor variables. The noise removal is done by truncating the SVD matrices up to a few largest singular value components, and then reconstructing a denoised data matrix by using the remaining singular vectors. In electronic nose systems this method seems to be very effective in reducing noise components arising from both the odor sampling and delivery system and the sensors electronics. The feature extraction by principal component analysis based on the SVD denoised data matrix is seen to reduce separation between samples of the same class and increase separation between samples of different classes. This is beneficial for improving classification efficiency of electronic noses by reducing overlap between classes in feature space. The efficacy of SVD denoising method in electronic nose data analysis is demonstrated by analyzing five data sets available in public domain which are based on surface acoustic wave (SAW) sensors, conducting composite polymer sensors and the tin-oxide sensors arrays. © 2006 IEEE.
Mandibular Ramus: An Indicator for Sex in Fragmentary Mandible
(2011) Saini, Vineeta; Srivastava, Rashmi; Rai, Rajesh K.; Shamal, Satya N.; Singh, Tej B.; Tripathi, Sunil K.
Mandible is the hardest and most durable bone of the skull exhibiting a high degree of sexual dimorphism. Especially ramus of mandible is subjected to greater stress than any other bone of the skull because of the process of mastication. This study has been performed to establish the osteometric standards for practical use in forensic context over Indian population using mandibular ramus. The sample consists of 116 mandibles of Northern Indian population (M:F; 92:24, mean age 37.4 years), collected from the Department of Forensic Medicine, IMS, BHU, Varanasi. Osteometric informations about five metric parameters (coronoid height, projective height, condylar height, and maximum breadth and minimum breadth of ramus) were taken with sliding calipers. These parameters were subjected to different discriminant function analysis using SPSS 16.0. All parameters showed significant sexual dimorphism (p < 0.001 in all cases) with an overall accuracy of 80.2%, and coronoid height was the single best parameter providing an accuracy of 74.1%. © 2010 American Academy of Forensic Sciences.
Studies on the synthesis and characterization of Zn1-xCd xS and Zn1-xCdxS:Mn2+ semiconductor quantum dots
(2011) Sakthi Sudar Saravanan, R.; Pukazhselvan, D.; Mahadevan, C.K.
Quantum dots (3-4 nm) of Zn1-xCdxS (both free of Mn2+ and with Mn2+ incorporated) were synthesized through a novel solvothermal-microwave irradiation technique. Detailed structural analysis of the Zn1-xCdxS and Zn1-xCd xS:Mn2+ (x = 0, 0.25, 0.5, 0.75 and 1) materials was carried out using powder X-ray diffraction technique. For all the compositions, the crystallite size was controlled to less than 1.5 nm. The optical energy gap for Zn1-xCdxS was found to vary from 3.878 to 2.519 eV and for Zn1-xCd1-xS:Mn2+ it varies from 3.830 to 2.442 eV when x is increased from 0 to 1. Overall, the optical energy gap could be tuned from a minimum of 2.442 eV to a maximum of 3.878 eV. DC conductivity analysis (from 40C to 150°C) and electrical energy gap analysis for all the compositions were also performed. The dc conductivity for Zn 1-xCd1-xS solid solutions varies from 0.3840 × 10-10 to 8.7782 × 10-10 mho/m at 150°C and for Zn1-xCd1-xS:Mn2+ it varies from 0.5751 × 10-10 to 9.8078 × 10-10 mho /m at 150°C (for x = 0 to x = 1). The method of synthesis and the results observed in this investigation may assist in the fabrication of optical devices when the required operational performance falls under the range observed in the study. © 2010 2011 Taylor & Francis.
Extracellular poly (A) specific ribonuclease from Aspergillus niger ATCC 26550: Purification, biochemical, and spectroscopic studies
(2011) Gundampati, R.K.; Sharma, Anurag; Kumari, Moni; Debnath, M.
Aspergillus niger RNase belonging to RNase T2 family is purified to homogeneity using ammonium sulfate precipitation and anion-exchange chromatography from A. niger. The enzyme is glycosylated monomer with molecule mass of 28.5 kDa. Optimum activity of the enzyme is achieved at pH 3.5 and temperature 55 °C. The enzyme shows broad substrate specificity with poly (A), poly (C), poly (G), poly (U) and yeast RNA. The enzyme is highly stable against various metal ions and organic solvents, thus dictates its applicability in various industries. Two peptide sequences, PGGTLLQTQFWDYDP and TLDSYTALSDAGITPSEDATYK obtained by MS/MS analysis and confirmed by BLAST search, show substantial sequence homology with Aspergillus phoenicis, Aspergillus clavatus and P. merneffei. Multiple sequence analysis of the peptide sequences of purified enzyme shows 97%, 75% and 72% identity with A. phoenicis, A. clavatus and P. merneffei, respectively using Clustal W tool. Spectroscopic studies by absorbance, fluorescence, and circular dichroism reveal that the enzyme has α+β type secondary structure with approximately 29% α-helix, 24% β-sheet and 47% random coil by K2D software. © 2010 Elsevier Ltd. All rights reserved.
Testosterone modulates pituitary vasotocin receptor expression and adrenal activity in osmotically stressed chicken
(Elsevier Inc., 2011) Sharma, Dharmendra; Chaturvedi, Chandra Mohini
Regulation of arginine vasotocin (AVT), avian neurohypophyseal hormone, is an important component of the hypothalamo-pituitary-adrenal axis. Changes in plasma osmolality levels and sex steroids are known to affect AVT gene expression. The present study reports the effect of water deprivation and testosterone treatment independently, as well as simultaneously, on the pituitary vasotocin receptor VT2R expression and adrenal steroidogenic activity in sexually immature male chicken (Gallus gallus). Birds were divided into four groups- control, water deprived (WD), testosterone injected (TE) and TE treated water deprived (TE. +. WD). WD decreased and TE treatment alone or in combination with WD (TE. +. WD) increased VT2R expression compared to the control. Expression of pro-opiomelanocortin (POMC) was also studied since this gene is a polypeptide precursor of ACTH and is under the negative feedback of adrenal corticoids. TE treatment as well as WD separately or when coupled together decreased the POMC mRNA expression in the pituitary but stimulated adrenal steroidogenic activity. Further, VT2R expression decreased in TE. +. WD compared to TE group, but it was not different from the vehicle treated control group suggesting that the suppressive effect of WD on VT2R expression was inhibited by the stimulatory effect of testosterone. Similarly, although both TE and WD decreased POMC expression and increased steroidogenic activity, no further decrease or increase in these parameters was observed when these two (WD and TE) treatments were combined together. Although, the exact mechanism is not clear, data indicate a stimulatory action of testosterone on VT2R expression and adrenal function despite a decreased expression of POMC mRNA. Results also suggest that testosterone treatment to sexually immature birds, in addition to its effect on hypothalamic AVT neurons (earlier study) and pituitary VT2R expression (present study), masks or inhibits osmotic stress-induced alterations in pituitary-adrenal activity. © 2010 Elsevier Inc.
Recombinant YopJ induces apoptotic cell death in macrophages through TLR2
(2011) Pandey, Ashok Kumar; Sodhi, Ajit
Bacterial species evolved evasive maneuvers to bypass their recognition by the receptors primarily TLRs of the innate immune cells. We have reported that 3 μg/ml of recombinant YopJ when provided extracellularly induced apoptosis in murine peritoneal macrophages in vitro. The present investigations demonstrate the role of TLR2 in apoptotic signals induced by rYopJ protein in murine peritoneal macrophages. The role of TLR2 in rYopJ induced macrophage apoptosis was shown by neutralization experiments and its co-immunoprecipitation with downstream molecule MyD88. The observed functional consequence of TLR2 neutralization were the inhibition of caspase-8 and caspase-3 activation, change in mitochondrial membrane potential (Δψm) and DNA fragmentation induced by rYopJ in macrophages. Further, rYopJ induced enhanced expression of IRAK-4, FADD, phosphorylation of IκB and p38 MAP kinase in macrophages. Pharmacological inhibitor of p38 MAP kinase and neutralization of TLR2 with neutralizing antibodies significantly inhibited the rYopJ induced caspases activation and DNA fragmentation, suggesting the possible involvement of TLR2 and p38 MAP kinase in rYopJ induced macrophages apoptosis. © 2010 Elsevier Ltd.
Reproductive phase dependent variation in lungassociated immune system (lais) and expression of melatonin receptors (mel1a and mel1b) in the lung of the jungle-bush quail (perdicula asiatica)
(2011) Kharwar, R.K.; Haldar, C.
The present study was performed to assess the variation of the lung-associated immune system (LAIS) in the Jungle-Bush Quail (Perdicula asiatica (Latham, 1790)) during two different reproductive phases when differences in the circulatory level of hormones (melatonin and gonadal steroid) and environmental conditions were maximum. We noted high significant variation in size and number of bronchus-associated lymphoid tissue (BALT) nodules, as well as in the size and number of non-BALT nodules, during the reproductively inactive phase (RIP; December) compared with the active phase (RAP; June). We also noted high significant variation in the percent stimulation ratio of lung lymphocyte, as well as in the concentrations of plasma melatonin and melatonin receptors, during RIP compared with RAP. Testosterone level and number of macrophages in lungs were high during RAP. Thus, we suggest that the LAIS had reproductive phase dependent variation, which could be due to (i) variation in environmental factors (photoperiod, temperature, and humidity) and (ii) circulatory level of hormones (melatonin and testosterone). Because of the importance of melatonin in avian immune regulation, we assess and document the expression of melatonin receptor types Mel1a and Mel1b in the avian lung, which suggest that the lung is a target organ for melatonin and that melatonin is an immunomodulator for lung-associated immunity in birds.
2-Deoxy-D-glucose reverses the Indian red scorpion venom-induced cardiopulmonary abnormalities in anesthetized rats
(2011) Choudhry, P.K.; Pandey, R.; Deshpande, S.B.
Role of 2-Deoxy-D-glucose (2-DG) in reversing the Indian red scorpion (Mesobuthus tamulus concanesis Pocock, MBT) venom-induced toxicity was examined. Femoral arterial pressure, ECG and respiratory movements were recorded in urethane anesthetized rats. Plasma glucose and serum insulin levels were also estimated. Intravenous injection of 5 mg/kg MBT venom produced immediate decrease in mean arterial pressure, heart rate and respiratory frequency followed by an increase and subsequent progressive decrease. ECG pattern exhibited ischaemic changes. There was hyperinsulinemia after venom without corresponding decrease in plasma glucose. The animals died within 37±9 min and demonstrated significant increase in pulmonary water content. 2-DG pretreatment (0.5 g/kg, iv) improved the cardiopulmonary abnormalities induced by venom and the animals survived for nearly 120 min. There was no hyperinsulinemia and increased pulmonary water content in these animals. In insulin (2 IU/kg) treated rats, the MBT venom-induced cardiopulmonary abnormalities were attenuated and ECG abnormalities were reversed. The pulmonary water content in these animals exhibited a decreasing trend and the animals survived for 120 min. Repaglinide (10 μg/kg, iv) pretreatment failed to reverse the venom-induced cardiopulmonary changes including the increased pulmonary water content. The survival time was similar to venom only group. The present results reveal that 2-DG reverses the venom-induced cardiopulmonary toxicity probably by restoring insulin sensitivity.
Modal analysis and cutoff frequencies of a doubly clad plasma loaded waveguide having a lemniscates of Bernoulli-type core cross-section
(2011) Janma, R.; Jatan, R.; Singh, S.P.; Dwivedi, P.; Dwivedi, V.; Singh, Vivek
The modal dispersion characteristics of EM waves in a new unconventional plasma loaded doubly clad waveguide having a shape of the lemniscates of Bernoulli-type core cross-section have been studied analytically. The proposed waveguide has three parts namely the core with slighter high index, the inner cladding with plasma and the outer cladding with air. Now using the necessary orthogonal coordinates for the proposed structure and imposing the boundary conditions under the weak guidance condition, the modal characteristics equation has been obtained considering variations in plasma width and plasma frequency, the dispersion curves and cutoff frequencies have been obtained and presented in this paper. It is noted that as the width of plasma layer increases, the cutoff frequency also increases considerably in all considered cases. This shows that using plasma width as a new parameter we can control any particular mode on our wish. © 2010 Published by Elsevier GmbH.
Differential localization and processing of apoptotic proteins in Malpighian tubules of Drosophila during metamorphosis
(2011) Shukla, Anukampa; Tapadia, Madhu G.
Drosophila development proceeds through three larval stages, before it pupates to reach adulthood. During pupation, larval tissues are destructed by programmed cell death and replaced by adult structures. Programmed cell death is a tightly regulated process accomplished by the induction of three closely linked pro-apoptotic genes reaper, hid and grim, ultimately leading to the activation of caspases, DRONC and DRICE and results in cell death. Unlike other larval tissues, Malpighian tubules are unique in not undergoing characteristic ecdysone-induced apoptosis and are carried to the adults. In this paper we show that apoptotic proteins, HID, GRIM, DRONC and DRICE are expressed in the Malpighian tubules, however they are sequestered in the nucleus. Significantly DRONC and DRICE are not enzymatically processed to active forms in the Malpighian tubules, however, ectopic expression of pro-apoptotic proteins leads to malformed Malpighian tubules and lethality. We also show that the Drosophila inhibitor of apoptotic protein 1, DIAP1, is localized and processed differently in Malpighian tubules. These results provide first evidence in favor of differential activity of apoptotic proteins in Malpighian tubules. © 2010 Elsevier GmbH.
Identification of legume RopGEF gene families and characterization of a Medicago truncatula RopGEF mediating polar growth of root hairs
(2011) Riely, Brendan K.; He, Hengbin; Venkateshwaran, Muthusubramanian; Sarma, Birinchi; Schraiber, Joshua; Ané, Jean-Michel; Cook, Douglas R.
Summary Root hairs play important roles in the interaction of plants with their environment. Root hairs anchor the plant in the soil, facilitate nutrient uptake from the rhizosphere, and participate in symbiotic plant-microbe interactions. These specialized cells grow in a polar fashion which gives rise to their elongated shape, a process mediated in part by a family of small GTPases known as Rops. RopGEFs (GEF, guanine nucleotide exchange factor) activate Rops to effect tip growth in Arabidopsis pollen and root hairs, but the genes mediating tip growth in legumes have not yet been characterized. In this report we describe the Rop and RopGEF gene families from the model legume Medicago truncatula and from the crop legume soybean. We find that one member of the M. truncatula gene family, MtRopGEF2, is required for root hair development because silencing this gene by RNA interference affects the cytosolic Ca 2+ gradient and subcellular structure of root hairs, and reduces root hair growth. Consistent with its role in polar growth, we find that a GFP
Study of thermally activated a.c. conduction in a-Se80Te 20 and a-Se80Te19.5M0.5 (M = Cd, In, Sb) alloys
(2011) Chandel, N.; Mehta, N.; Kumar, A.
The temperature and frequency dependence of a.c. conductivity in a-Se 80Te20 and a-Se80Te19.5M 0.5 (M = Cd, In, Sb) alloys have been investigated. Measurements have been carried out for the frequency range 0.5 kHz-10 kHz in the temperature range from room temperature to glass transition temperature. The a.c. conductivity σac is found to be proportional to ωs where s < 1. The temperature dependence of both σac and the parameter s is reasonably well interpreted by the correlated barrier hopping (CBH) model. © 2010 Elsevier Masson SAS. All rights reserved.
Supplemental ultraviolet-B and ozone: Impact on antioxidants, proteome and genome of linseed (Linum usitatissimum L. cv. Padmini)
(2011) Tripathi, R.; Sarkar, A.; Pandey Rai, S.; Agrawal, S.B.
The present investigation used Linum usitatissimum L. cv. Padmini (linseed), under field conditions in open-top chambers, to evaluate the interactive effects of supplemental ultraviolet-B (sUV-B; ambient +7.2 kJ.m-2.d-1) and ozone (O3; ambient +10 ppb). Treatment of plants with sUV-B and O3, individually or in combination, caused several changes in enzymatic and non-enzymatic components of the antioxidant defence system. Photo-oxidative damage caused by sUV-B and O3, included lipid peroxidation, changed protein profiles and caused DNA strand breakage. One-dimensional gel electrophoresis revealed that proteins of 222.24 and 50.5 kDa are specific and appear after sUV-B and O3 exposure, and could be used as indicator proteins. Effects of sUV-B and O3 given separately are more detrimental as compared to combined treatment. Mutational and structural alterations in linseed DNA after these stresses were also examined using RAPD with ten different primers. The study concluded that both stresses, i.e. sUV-B and O3, are phytotoxic, causing significant changes in metabolites, antioxidants, the leaf proteome and the genome of linseed, but their interactive effect was always less than additive. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.
Negative regulation of fibrin polymerization and clot formation by nanoparticles of silver
(2011) Shrivastava, Siddhartha; Singh, Sunil K.; Mukhopadhyay, Avijit; Sinha, Akhoury S.K.; Mandal, Rajiv K.; Dash, Debabrata
Thrombolytic therapy in acute stroke has reduced ischemia; however, it is also associated with increased incidence of intracerebral hemorrhage and expanding stroke. Platelets and fibrin are the major components of thrombi. Since fibrin is available in large concentration at lesion sites and in all types of thrombi, it is an obvious target for majority of antithrombotic therapies. Previously we have demonstrated innate antiplatelet properties with nanosilver. It can effectively prevent platelet activation in response to physiological agonists, under both in vitro as well as ex vivo conditions, and immobilize and stabilize proteins. Here we report for the first time that nanosilver can significantly retard fibrin polymerization kinetics both in pure and plasma-incorporated systems and hence can impede thrombus formation. We also discuss the conformational changes ensued upon fibrinogen following interaction with nanosilver. Together with its inherent antiplatelet and antibacterial properties, capacity to inhibit fibrin polymerization can open up possibilities of newer biomedical application and research potential involving silver nanoparticles. © 2010 Elsevier B.V.

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