Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 121
Filter
1.
RSC Adv ; 10(71): 43497-43507, 2020 Nov 27.
Article in English | MEDLINE | ID: mdl-35519712

ABSTRACT

Crystallographic and electronic structures of phase pure ternary solid solutions of Ni1-x Co x O (x = 0 to 1) have been studied using XRD, EXAFS and XAS measurements. The lattice parameter of the cubic rock-salt (RS) Ni1-x Co x O solid solutions increases linearly with increasing Co content and follows Vegard's law, in the complete composition range. A linear increase in the bond lengths (Ni/Co-O, Ni-Ni and Ni-Co) with "x", closely following the bond lengths determined from virtual crystal approximation (VCA), is observed, which implies that there is only a minimal local distortion of the lattice in the mixed crystal. The optical gap of the ternary solid solution determined from diffuse reflectivity measurements shows neither a linear variation with Co composition nor bowing, as observed in many ternary semiconductors. This trend in the variation of optical gaps is explained by probing the conduction band using XAS at the O K-edge. We have observed that the variation in the onset energy of the conduction band edge with "x" is very similar to the variation in the optical gap with "x", thus clearly indicating the dominant role played by the conduction band position in determining the optical gap. The variation in the intensities of the pre-edge peak in the XANES spectra measured at Ni and Co K-edges, and the L1/2 peak in XAS spectra measured at Ni and Co L-edges, is found to depend on the unoccupied O 2p-metal-(Ni/Co) 3d hybridized states and the bond lengths.

2.
Virusdisease ; 30(3): 441-452, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31803812

ABSTRACT

Newcastle disease (ND) and avian influenza (AI) are economically important infectious diseases of poultry. Sometime, concomitant secondary viral/or bacterial infections significantly alters the pathobiology of ND and AI in poultry. As of now, the disease patterns and dynamics of co-infections caused by ND virus (NDV, genotype XIII) and Low Pathogenic AI viruses (LPAI, H9N2) are explicitly elusive. Thus, we examined the clinicopathological disease conditions due to these two economically important viruses to understand the complex disease outcomes by virus-virus interactions in vaccinated flocks. The findings of clinicopathological and molecular investigations carried on 37 commercial ND vaccinated poultry flocks revealed simultaneous circulation of NDV and AIV in same flock/bird. Further, molecular characterization of hemagglutinin (HA) and neuraminidase (NA) genes confirmed that all the identified AIVs were of low pathogenicity H9N2 subtype and fusion (F) gene analysis of detected NDVs belong to NDV class II, genotype XIII, a virulent type. The NDV and H9N2 alone or co-infected flocks (NDV + LPAI) exhibit clinical signs and lesions similar to that of virulent NDV except the degree of severity, which was higher in H9N2-NDV co-infected flocks. Additionally, avian pathogenic E. coli and mycoplasma infections were detected in majority of the ailing/dead birds from the co-infected flocks during progression of the clinical disease. Overall, the findings highlight the multi-factorial disease complexity in commercial poultry and suggest the importance of NDV genotype XIII in intensifying the clinical disease in vaccinated birds.

3.
Environ Monit Assess ; 191(4): 223, 2019 Mar 16.
Article in English | MEDLINE | ID: mdl-30879142

ABSTRACT

Phosphorus (P) demand is likely to increase especially in legumes to harness greater benefits of nitrogen fixation under elevated CO2 condition. In the following study, seed yield and seed P uptake in cowpea increased by 26.8% and 20.9%, respectively, under elevated CO2 level. With an increase in phosphorus dose up to 12 mg kg-1, seed yield enhanced from 2.6 to 5.4 g plant-1. P application and cyanobacterial inoculation increased the microbial activity of soil, leading to increased availability of P. Under elevated CO2 condition, microbial activity, measured as dehydrogenase, acid phosphatase, and alkaline phosphatase activities showed stimulation. Soil available P also increased under elevated CO2 condition and was stimulated by both P application and cyanobacterial inoculation. Higher P uptake in elevated CO2 condition led to lower values of inorganic P in soil. Stepwise regression analysis showed that aboveground P uptake, soil available P, and alkaline phosphatase activity of soil influenced the yield while available P, and organic and inorganic P influenced the aboveground P uptake of the crop. This study revealed that under elevated CO2 condition, P application and cyanobacterial inoculation facilitated P uptake and yield, mediated through enhanced availability of nutrients, in cowpea crop.


Subject(s)
Carbon Dioxide/metabolism , Cyanobacteria/metabolism , Phosphorus/metabolism , Vigna/metabolism , Carbon , Carbon Dioxide/analysis , Environmental Monitoring , Nitrogen , Nitrogen Fixation , Regression Analysis , Soil/chemistry , Vigna/growth & development
4.
Environ Monit Assess ; 190(11): 661, 2018 Oct 22.
Article in English | MEDLINE | ID: mdl-30345462

ABSTRACT

To see the effect of climate change on the variation of soil hydrothermal regimes and growth of maize crop, an experiment was conducted in free-air carbon dioxide enrichment (FACE) facility during the kharif season of 2015 at Climate Change Facility of Indian Agricultural Research Institute, New Delhi, India. Under elevated CO2 and ambient condition, surface bulk density (BD) were 1.38 Mgm-3 and 1.44 Mgm-3, respectively but BD were not significantly different. During different days after sowing (DAS), in 0 to 10-cm soil depth, soil water content (SWC) in FACE varied between 14.58-20.70%, whereas in ambient condition, SWC variations were in between 19.33-22.94%. In 10 to 20-cm soil depth, SWC ranged in between 20.47-27.14% in FACE and 23.57-25.42% in ambient condition for different DAS. It is also observed that the arrival of peak surface ST was 1 h early in elevated CO2 condition. Photosynthetic rate increased by 5.7% on 44 DAS and 18.1% on 70 DAS under elevated carbon dioxide condition. Elevated carbon dioxide had reduced the stomatal conductance but the reduction was not significant. Like variation in air temperature for climate change, more intensive study is required to see the effect of climate change on soil temperature and its effect on crop growth.


Subject(s)
Carbon Dioxide/analysis , Environmental Monitoring/methods , Soil/chemistry , Zea mays/growth & development , Agriculture , Air/analysis , Climate Change , India , Photosynthesis , Seasons , Temperature , Water/chemistry
5.
Virusdisease ; 29(3): 349-354, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30159370

ABSTRACT

Marek's disease (MD) and lymphoid leucosis (LL) are the major diseases causing lymphoid tumors in chickens accounting for high economical losses. Gross examination could not yield definite diagnosis owing to their similar presentation of lesions. Thus present work was aimed for diagnosis and differentiation of MD and LL by utilizing simple cytology and novel immunocytology techniques. Cytological examination was carried out on slides with tumor touch imprints stained by simple Giemsa staining. The diagnosis was mainly achieved based on morphology of cell population. In the present study, out of a total of 595 cases examined, 502 cases had pleomorphic lymphocytic cell population suggestive of MD and 53 cases had uniform lymphocytic/lymphoblast cell population suggestive of LL, while the rest 40 cases remained inconclusive. A definitive diagnosis was achieved after performing immunocytology using specific antibodies that revealed 518 cases had reactivity for Meq oncoprotein specific for MD and 77 cases showed immunoreactivity for IgM in transformed B-cells confirming LL. The technique of immunocytology which has been useful for detecting human viral pathogens and MD in poultry has been applied for the first time as a novel, simple, rapid and inexpensive technique that could be used as an alternate test to effectively detect and differentiate MD and LL in poultry.

6.
Environ Monit Assess ; 190(4): 217, 2018 Mar 14.
Article in English | MEDLINE | ID: mdl-29541935

ABSTRACT

An attempt has been made to study the effect of elevated temperature on soil hydrothermal regimes and winter wheat growth under simulated warming in temperature gradient tunnel (TGT). Results showed that bulk density (BDs) of 0, 0.9, and 2.5 °C were significantly different whereas BDs of 2.8 and 3.5 °C were not significantly different. Water filled pore space (WFPS) was maximum at 3.5 °C temperature rise and varied between 43.80 and 98.55%. Soil surface temperature (ST) at different dates of sowing increased with rise in sensor temperature and highest ST was observed at S5 sensors (3.5 °C temperature rise). Temperature and its difference were high for the top soil, and were stable for the deep soil. Photosynthesis rate (µmol CO2 m-2 s-1) of wheat was lower at higher temperature in different growth stages of wheat. In wheat, stomatal conductance declined from 0.67 to 0.44 mol m-2 s-1 with temperature rise. Stomatal conductance decreased with increase in soil temperature and gravimetric soil moisture content (SWC). In TGT, 0 °C temperature rise showed highest root weight density (RWD) (5.95 mg cm-3); whereas, 2.8 and 3.5 °C showed lowest RWD (4.90 mg cm-3). Harvest index was maximum (0.37) with 0 °C temperature rise, and it decreased with increase in temperature, which indicated that both grain and shoot biomass decreased with increase in temperature. Intensive studies are needed to quantify the soil hydrothermal regimes inside TGT along with the crop growth parameters.


Subject(s)
Environmental Monitoring , Soil/chemistry , Temperature , Triticum/physiology , Biomass , Carbon Dioxide/analysis , Edible Grain/chemistry , Photosynthesis , Plant Roots/chemistry , Seasons , Triticum/growth & development , Water
7.
Kathmandu Univ Med J (KUMJ) ; 16(61): 65-68, 2018.
Article in English | MEDLINE | ID: mdl-30631020

ABSTRACT

Background Neonates born through meconium stained amniotic fluid (MSAF) are associated with significant morbidity and mortality. Objective To study the incidence, associated factors and outcome of meconium stained amniotic fluid babies born in Dhulikhel hospital. Method Prospective, cross-sectional study conducted in Obstetric ward and Neonatal Intensive Care Unit (NICU) from 15 December 2015 to 15 December 2016. All the babies born through meconium stained amniotic fluid during the period were included. Result Incidence of meconium stained amniotic fluid was 6.5%(167/2581). Meconium aspiration syndrome (MAS) developed in 9(5.4%) among all meconium stained amniotic fluid cases. Primigravidity and postdatism were observed more in Meconium aspiration syndrome group than meconium stained amniotic fluid group (77.8% VS 73.4%; 33.3% VS 26.3%). Babies delivered by caesarian section were more in meconium stained amniotic fluid group than Meconium aspiration syndrome group (47.5% VS 33.3%). All the babies with meconium stained amniotic fluid improved except one baby with Meconium aspiration syndrome who expired. Neonatal sepsis was a significant co-morbidity in Meconium aspiration syndrome group (P value= 0.008). There was increased incidence of operative delivery in thick meconium stained amniotic fluid than thin meconium stained amniotic fluid (52.6% VS 38.9%). Similarly, Neonatal Intensive Care Unit admission and neonatal complications like Meconium aspiration syndrome, perinatal asphyxia and sepsis were more commonly observed in thick meconium stained amniotic fluid group than thin meconium stained amniotic fluid group. Conclusion The progression to meconium aspiration syndrome in babies with meconium stained amniotic fluid is not associated with any maternal and neonatal factors studied. MAS babies are 10 times more likely to require NICU admission and sepsis is a significant co-morbidity. Thick meconium stained amniotic fluid is worrisome. There is increased chance of operative delivery and neonatal complications if associated with thick meconium stained amniotic fluid.


Subject(s)
Amniotic Fluid , Meconium , Asphyxia Neonatorum/etiology , Cross-Sectional Studies , Female , Humans , Incidence , Infant, Newborn , Meconium Aspiration Syndrome/complications , Meconium Aspiration Syndrome/etiology , Pregnancy , Pregnancy Complications , Prospective Studies , Sepsis
8.
Water Environ Res ; 90(2): 101-109, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-28600862

ABSTRACT

This paper presents the biophysical impact of various interventions made under watershed development programs, in terms of the creation of additional water resources, and resultant changes in land use and cropping patterns in the Bundelkhand region of Madhya Pradesh State, India. Both primary and secondary data gathered from randomly selected watersheds and their corresponding control villages were used in this study. Analysis revealed that emphasis was given primarily to the creation of water resources potential during implementation of the programs, which led to augmentation of surface and groundwater availability for both irrigation and non-agricultural purposes. In addition, other land based interventions for soil and moisture conservation, plantation activities, and so forth, were taken up on both arable and nonarable land, which helped to improve land slope and land use, cropping pattern, agricultural productivity, and vegetation cover.


Subject(s)
Agriculture/methods , Conservation of Natural Resources/methods , Water Resources/supply & distribution , Water Supply/methods , India , Soil , Water Supply/statistics & numerical data
9.
Virusdisease ; 28(1): 115-120, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28466063

ABSTRACT

Chicken infectious anaemia virus (CIAV) is an economically important and a highly immunosuppressive virus affecting poultry industry worldwide. In this study we assessed the immunomodulatory effects of four herbal preparations namely Withania somnifera, Tinospora cordifolia, Azadirachta indica and E Care Se Herbal in resisting the viral multiplication and immunosuppression inflicted by CIAV in chicks. Day-old chicks (n = 90) were randomly and equally divided into six groups (Groups A-F). Groups A-D were administered with purified extracts of W. somnifera, T. cordifolia, A. indica and E Care Se Herbal, respectively followed by the evaluation of viral load in lymphoid organs by quantitative real-time PCR and cell mediated immune response by flow cytometric analysis of CD4+ and CD8+ T cells. Groups A-D were found to resist CIAV multiplication and pathogenesis with significant reduction of viral load compared with the infected control (P < 0.05). Group A-C chicks showed significantly higher (P < 0.05) CD4+ and CD8+ T cell counts compared to control birds while of E Care Se Herb had minimal effect on T cell count. The findings suggested that the herbal preparations used during the study were effective as both prophylactic and immunomodulatory agents and thus have potential of being used against CIAV induced immunosuppression in poultry.

10.
Microb Pathog ; 105: 8-12, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28163156

ABSTRACT

Newcastle disease (ND) is an economically important viral disease distressing poultry industry across the globe. Herein, we report the clinicopathology of sub-genotype VIIi Newcastle disease virus (NDV) isolated from peafowl in chickens. The virus isolate produced systemic infection with prominent tropism in visceral organs in chicken, confirmed on the basis of gross and microscopic lesions, and immunohistochemistry findings. The experimentally infected chickens exhibited 100% mortality with severe hemorrhagic lesions in the proventriculus and intestine, especially marked lymphocytolysis in spleen and bursa. The virus could be re-isolated from the cloacal swabs of infected chickens during 4th to 6th dpi (on 6th dpi all birds died), and all were tested positive in conventional RT-PCR. This is the first report on clinicopathology of NDV isolated from peafowl and/or sub-genotype VIIi NDV in experimentally infected chickens. Explorative epidemiological and molecular studies are suggested to screen wild peafowls and poultry flocks of the country for establishing the occurrence of this sub-genotype and opting for appropriate prevention and control strategies.


Subject(s)
Newcastle Disease/pathology , Newcastle Disease/virology , Newcastle disease virus/growth & development , Newcastle disease virus/pathogenicity , Poultry Diseases/pathology , Poultry Diseases/virology , Animal Experimentation , Animal Structures/pathology , Animal Structures/virology , Animals , Birds , Chickens , Histocytochemistry , Immunohistochemistry , Microscopy , Newcastle disease virus/isolation & purification , Survival Analysis
11.
Radiat Prot Dosimetry ; 175(4): 493-502, 2017 Aug 01.
Article in English | MEDLINE | ID: mdl-28096312

ABSTRACT

The suitability of the second derivative method for locating component peaks in complex thermoluminescence (TL) glow curves has been investigated in this work by considering both numerically simulated and experimental TL peaks. This technique is useful to acquire knowledge of the number of component peaks in a complex TL curve which in turn serves as a basic information before applying the deconvolution technique to the glow curve. To check the consistency of the results so obtained, we have also applied the first derivative technique to TL glow curves. It is well-known that kinetic order formalism fails for saturated TL peaks with heavy retrapping. Such peaks are usually broad and, to the best of our knowledge, have not yet been observed experimentally. The present derivative technique has been used to detect whether such broad peaks are truly single or not by considering a number of numerically simulated saturated glow curves with heavy retrapping where the conventional peak shape method fails. In all the cases considered here, the second derivative technique proves to be a potential candidate for estimating the number of peaks and their respective locations in a complex TL glow curve.


Subject(s)
Thermoluminescent Dosimetry , Kinetics , Luminescent Measurements
12.
J Virol Methods ; 236: 271-280, 2016 10.
Article in English | MEDLINE | ID: mdl-27528486

ABSTRACT

Marek's disease (MD), is an economically important virus disease of poultry throughout the world. In this study, we for the first time reports development of a novel dot enzyme-linked immunosorbent assay (dot-ELISA) for the confirmatory diagnosis of lymphoma caused by Marek's Disease Virus (MDV). Suspected lymphoma tissue extracts from the diseased birds were used for the Meq oncoprotein antigen detection, which is expressed specifically in MDV lymphomas. Recombinant Meq oncoprotein was expressed using Expresso™ Rhamnose Sumo Cloning and Expression system and the hyperimmune serum was raised against it, which was used later while developing dot-ELISA. The dot-ELISA exhibited higher specificity (92%) in diagnosing MD lymphomas as compared to conventional PCR (40%), where later assay is unable to differentiate disease development (lymphoma) and/or infection. The developed dot-ELISA proved to be a specific, rapid and inexpensive technique detecting MDV lymphomas in poultry. Of the note, this new assay could be opted as a valuable diagnostic tool in the resource poor countries andcould further be used to differentiate from other tumor causing viruses in poultry.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Lymphoma/etiology , Marek Disease/diagnosis , Oncogene Proteins, Viral/analysis , Poultry Diseases/diagnosis , Animals , Costs and Cost Analysis , Marek Disease/complications , Sensitivity and Specificity , Time Factors
13.
Virusdisease ; 27(2): 203-6, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27366774

ABSTRACT

The study details characterization of Newcastle disease virus (NDV) isolates recovered from commercial poultry flocks (chicken) and wild birds (crane) of India during the time period from 1989 to 2013. Phylogenetic analysis revealed that most of the NDV isolates belongs to class II, genotype XIIIa and a chicken isolate (108/BAREILLY/AD-IVRI/91) was of genotype VI, where it showed diversity of 3 % from the other viruses belonging to same genotype. Another chicken isolate (75/RAMPUR/AD-IVRI/89) grouped in genotype III and showed 4 % diversity with viruses of genotype III. The crane origin NDV identified as of genotype II corresponding to the vaccine virus. This appears to be the first report about existence of genotype XIIIa and its ancestral viruses are circulating in India for the last two decades in different species of birds. Furthermore, genetically distinct viruses belonging to genotypes II, III and VI are also circulating in India.

14.
J Biomech ; 49(10): 2076-2084, 2016 07 05.
Article in English | MEDLINE | ID: mdl-27255604

ABSTRACT

Aortic root motion was previously identified as a risk factor for aortic dissection due to increased longitudinal stresses in the ascending aorta. The aim of this study was to investigate the effects of aortic root motion on wall stress and strain in the ascending aorta and evaluate changes before and after implantation of personalised external aortic root support (PEARS). Finite element (FE) models of the aortic root and thoracic aorta were developed using patient-specific geometries reconstructed from pre- and post-PEARS cardiovascular magnetic resonance (CMR) images in three Marfan patients. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Cardiovascular MR cine images were used to quantify aortic root motion, which was imposed at the aortic root boundary of the FE model, with zero-displacement constraints at the distal ends of the aortic branches and descending aorta. Measurements of the systolic downward motion of the aortic root revealed a significant reduction in the axial displacement in all three patients post-PEARS compared with its pre-PEARS counterparts. Higher longitudinal stresses were observed in the ascending aorta when compared with models without the root motion. Implantation of PEARS reduced the longitudinal stresses in the ascending aorta by up to 52%. In contrast, the circumferential stresses at the interface between the supported and unsupported aorta were increase by up to 82%. However, all peak stresses were less than half the known yield stress for the dilated thoracic aorta.


Subject(s)
Aorta, Thoracic/physiopathology , Aorta/physiopathology , Blood Vessel Prosthesis , Marfan Syndrome/physiopathology , Aorta/surgery , Aorta, Thoracic/surgery , Blood Pressure , Finite Element Analysis , Humans , Marfan Syndrome/surgery , Movement , Systole
15.
J Biomech ; 49(1): 100-111, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26654673

ABSTRACT

Implantation of a personalised external aortic root support (PEARS) in the Marfan aorta is a new procedure that has emerged recently, but its haemodynamic implication has not been investigated. The objective of this study was to compare the flow characteristics and hemodynamic indices in the aorta before and after insertion of PEARS, using combined cardiovascular magnetic resonance imaging (CMR) and computational fluid dynamics (CFD). Pre- and post-PEARS MR images were acquired from 3 patients and used to build patient-specific models and upstream flow conditions, which were incorporated into the CFD simulations. The results revealed that while the qualitative patterns of the haemodynamics were similar before and after PEARS implantation, the post-PEARS aortas had slightly less disturbed flow at the sinuses, as a result of reduced diameters in the post-PEARS aortic roots. Quantitative differences were observed between the pre- and post-PEARS aortas, in that the mean values of helicity flow index (HFI) varied by -10%, 35% and 20% in post-PEARS aortas of Patients 1, 2 and 3, respectively, but all values were within the range reported for normal aortas. Comparisons with MR measured velocities in the descending aorta of Patient 2 demonstrated that the computational models were able to reproduce the important flow features observed in vivo.


Subject(s)
Aorta/physiopathology , Aortic Valve/physiopathology , Marfan Syndrome/physiopathology , Adult , Aorta, Thoracic/pathology , Blood Flow Velocity , Computer Simulation , Female , Hemodynamics , Humans , Hydrodynamics , Magnetic Resonance Imaging , Male , Middle Aged , Models, Statistical , Shear Strength , Stress, Mechanical , Young Adult
16.
J Environ Biol ; 36(1): 289-94, 2015 Jan.
Article in English | MEDLINE | ID: mdl-26536806

ABSTRACT

In the present study, out of four alleles amplified from seabass (Lates calcarifer) genome inhabiting Mumbai water by PCR using growth hormone (GH) gene-specific primers, two DNA fragments (SGMS1, 233 bp and SGMS2, 239 bp) were eluted from gel, cloned using pTZ57R (2.886 kb) vector into E. coli DH5α, characterized by restriction endonuclease analysis and sequenced by automated DNA sequencer. After blasting and multiple alignment of the above sequences, SGMS1 showed 97% and SGMS2 93.3% homology with promoter region of GH gene containing microsatellite of Australian seabass and 94.6% homology between both the fragments. These sequences SGMS1 and SGMS2 were submitted to NCBI GenBank. On blasting, these sequences with gene databases, SGMS1 and SGMS2 showed partial homologies with Seriola quinqueradiata (26.9%, 12.9%), flounder (15.8%, 15.8%), Oreochromis nilotica (23%, 7.9%), Oreochromis mossambicus (23%, 7.9%) and Danio rerio (8.2%, 7.5%). Critical analysis showed the presence of microsatellite (CA)16 and (CA)19 repeats in fragments SGMS1 and SGMS2, respectively in seabass from Mumbai water in comparison to (CA)14 repeats from the Australian seabass. Further, on sequence comparison, single nucleotide mismatches detected at their several positions in relation to seabass GH gene of Australia. These nucleotide variations detected in SGMS1 and SGMS2 in comparison to those of the Australian seabass may be due to mutations owing to environmental or habitat changes that seem to have definite potentials for development of genetic markers, which would be useful for identification and selection of superior germplasm with desirable commercial traits such as high growth rate.


Subject(s)
Bass/genetics , Dinucleotide Repeats/genetics , Growth Hormone/genetics , Animals , Base Sequence , Gene Expression Regulation , Growth Hormone/metabolism , India , Molecular Sequence Data
17.
Curr Microbiol ; 71(5): 585-93, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26271295

ABSTRACT

Gram-negative plant pathogenic bacteria regulate specific gene expression in a population density-dependent manner by sensing level of Acyl-Homoserine Lactone (HSL) molecules which they produce and liberate to the environment, called Quorum Sensing (QS). The production of virulence factors (extracellular enzyme viz. cellulase, pectinase, etc.) in Pectobacterium carotovorum subsp. carotovorum (Pcc) is under strong regulation of QS. The QS signal molecule, N-(3-oxohexanoyl)-L-Homoserine Lactone (OHHL) was found as the central regulatory system for the virulence factor production in Pcc and is also under strict regulation of external environmental temperature. Under seven different incubation temperatures (24, 26, 28, 30, 33, 35, and 37 °C) in laboratory condition, highest amount of OHHL (804 violacein unit) and highest (79 %) Disease Severity Index (DSI) were measured at 33 °C. The OHHL production kinetics showed accumulation of highest concentration of OHHL at late log phase of the growth but diminution in the concentration occurred during stationary phase onwards to death phase. At higher temperature (35 and 37 °C) exposure, OHHL was not at detectable range. The effect of temperature on virulence factor production is the concomitant effect of HSL production and degradation which justifies less disease severity index in cross-inoculated tomato fruits incubated at 35 and 37 °C. The nondetection of the OHHL in the elevated temperature may because of degradation as these signal molecules are quite sensitive and prone to get degraded under different physical factors. This result provides the rationale behind the highest disease severity up to certain elevated temperature and leaves opportunities for investigation on mutation, co-evolution of superior plant pathogen with more stable HSL signals-mediated pathogenesis under global warming context.


Subject(s)
Host-Pathogen Interactions , Microbial Interactions , Pectobacterium carotovorum/physiology , Plants/microbiology , Temperature , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/biosynthesis , Phenotype , Plant Diseases/microbiology , Quorum Sensing , Virulence/genetics
18.
Dalton Trans ; 44(33): 14793-8, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26219929

ABSTRACT

The lattice parameter variation for phase pure cubic rocksalt (RS) Ni1-xZnxO ternary solid solutions is observed to be perfectly governed by Vegard's law. X-ray absorption near edge spectroscopy confirms the RS symmetry of Zn atoms in the cubic lattice of Ni1-xZnxO. The optical gap bowing parameter for RS Ni1-xZnxO ternary solid solutions is determined, using diffuse reflectivity, to be -0.93 ± 0.05 eV. The negative value of the bowing indicates a repulsive interaction between the ligand O-2p and the metal Ni-3d orbitals. The determined value of the bowing parameter can be useful in designing UV photodetectors based on Ni1-xZnxO solid solutions.

19.
Med Eng Phys ; 37(8): 759-66, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26054807

ABSTRACT

Marfan syndrome is an inherited systemic connective tissue disease which may lead to aortic root disease causing dilatation, dissection and rupture of the aorta. The standard treatment is a major operation involving either an artificial valve and aorta or a complex valve repair. More recently, a personalised external aortic root support (PEARS) has been used to strengthen the aorta at an earlier stage of the disease avoiding risk of both rupture and major surgery. The aim of this study was to compare the stress and strain fields of the Marfan aortic root and ascending aorta before and after insertion of PEARS in order to understand its biomechanical implications. Finite element (FE) models were developed using patient-specific aortic geometries reconstructed from pre and post-PEARS magnetic resonance images in three Marfan patients. For the post-PEARS model, two scenarios were investigated-a bilayer model where PEARS and the aortic wall were treated as separate layers, and a single-layer model where PEARS was incorporated into the aortic wall. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Results from our FE models with patient-specific geometries show that peak aortic stresses and displacements before PEARS were located at the sinuses of Valsalva but following PEARS surgery, these peak values were shifted to the aortic arch, particularly at the interface between the supported and unsupported aorta. Further studies are required to assess the statistical significance of these findings and how PEARS compares with the standard treatment.


Subject(s)
Aorta/physiopathology , Aorta/surgery , Aortic Diseases/physiopathology , Aortic Diseases/surgery , Marfan Syndrome/physiopathology , Marfan Syndrome/surgery , Aorta/pathology , Aortic Diseases/etiology , Aortic Diseases/pathology , Blood Pressure , Blood Vessel Prosthesis , Cardiac-Gated Imaging Techniques , Computer Simulation , Elastic Modulus , Electrocardiography , Finite Element Analysis , Humans , Magnetic Resonance Imaging , Marfan Syndrome/complications , Marfan Syndrome/pathology , Models, Cardiovascular , Stress, Physiological , Treatment Outcome
20.
J Virol Methods ; 212: 47-52, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25449112

ABSTRACT

A rapid and accurate method of detection and differentiation of virulent and avirulent Newcastle disease virus (NDV) pathotypes was developed. The NDV detection was carried out for different domestic avian field isolates and pigeon paramyxo virus-1 (25 field isolates and 9 vaccine strains) by using APMV-I "fusion" (F) gene Class II specific external primer A and B (535bp), internal primer C and D (238bp) based reverses transcriptase PCR (RT-PCR). The internal degenerative reverse primer D is specific for F gene cleavage position of virulent strain of NDV. The nested RT-PCR products of avirulent strains showed two bands (535bp and 424bp) while virulent strains showed four bands (535bp, 424bp, 349bp and 238bp) on agar gel electrophoresis. This is the first report regarding development and use of degenerate primer based nested RT-PCR for accurate detection and differentiation of NDV pathotypes by demonstrating multiple PCR band patterns. Being a rapid, simple, and economical test, the developed method could serve as a valuable alternate diagnostic tool for characterizing NDV isolates and carrying out molecular epidemiological surveillance studies for this important pathogen of poultry.


Subject(s)
DNA Primers/genetics , Genotyping Techniques/methods , Newcastle disease virus/classification , Newcastle disease virus/genetics , Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , Genotype , Molecular Sequence Data , Newcastle disease virus/isolation & purification , RNA, Viral/genetics , Sequence Analysis, DNA , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...