67 research outputs found
Characterization of Sunn hemp begomovirus and its geographical origin based on in silico structural and functional analysis of recombinant coat protein
Sequence alignment of the 897 bp amplicon obtained from a diseased sunn hemp (Crotalaria juncea L.) plant DNA revealed a complete 771 bp coat protein (CP) gene flanked by 3â regions of the AV2 and AC3 genes. Southern hybridization using (α-32P) dCTP labeled (CP) gene probe of Indian tomato leaf curl virus (IToLCV) demonstrated the association of begomovirus with the leaf curl disease of sunn hemp. Phylogenetic data suggested that, the AV2, CP and AC3 genes have closest genetic relationship with begomovirus isolates from India, China and Bangladesh, respectively. In silico recombination analysis elucidated a 297 nucleotides hot spot (346 to 643 nucleotides) within AV2 overlapping region of CP gene, amenable to genetic rearrangements, with lineage from tomato leaf curl virus Bangalore (ToLCuVB) and Indian cassava mosaic virus-Ind (ICMV) as major and minor parents, respectively. Thus, it is concluded that the recombinant CP genes related to begomoviruses are evolved from the Indian isolates, causing broad host specificity and molecular diversity among the related begomoviruses across the geographical limits of Southeast Asia.Keywords: Begomovirus, sunn hemp, coat protein, recombination, phylogenetic analysis, in silico analysi
Biogenic Synthesis of Silver Nanoparticles Using Saraca indica Leaf Extract and Evaluation of Their Antibacterial Activity
The present study reports an unprecedented biogenic method for the synthesis of silver nanoparticles (AgNPs) using leaf extract of Saraca indica and characterized their antibacterial activity. We have also focused on the biosynthesis mechanism of AgNPs. Plant leaf extract has water soluble organic materials which help in the reduction of silver ions and stabilization of AgNPs. Aqueous solution of silver nitrate was treated with leaf extract of Saraca indica for the formation of AgNPs. The surface plasmon resonance was occurred at 412 nm. The size distribution profile of synthesized AgNPs was analysed by Dynamic Light Scattering (DLS). Transmission Electron Microscopy (TEM) has been done for the measurement of particle size and their morphology. The role of phytochemicals in the reduction of silver ions and defining the framework in which AgNPs are covered and provide steadiness can be determined through Fourier Transform Infrared Spectroscopy (FTIR). TEM micrograph reveals that the size of AgNPs was obtained in the range of 13-50 nm with spherical morphology. X-ray Diffraction (XRD) pattern of the AgNPs exhibited 2Ξ values corresponding to the silver nanocrystals. Furthermore, the antibacterial activity of synthesized AgNPs against E. coli DH5α was investigated by growth curve and inhibition zone analysis. It was observed that the 20 Όg/ml concentration of biogenic AgNPs recorded as minimal inhibitory concentration (MIC) against E. coli DH5α
Comparative assessment of TNF-α and C-reactive protein in patients subjected to open instead of laparoscopic cholecystectomy
Background : C-reactive protein (CRP) and tumor necrosis factor-α
(TNF- α) are specific proteins modulated by the acute stress of
surgery. Various retrospective and prospective studies have
demonstrated subdued stress responses in laparoscopically operated
patients vis-Ă -vis the conventional (open) method. Aim : To
assess the roles of TNF- α and C-reactive protein levels as
tentative stress markers in correlating the extent of perioperative
immune modulation during open and laparoscopic cholecystectomy in a
subset of an Indian population. Setting and Design : This study is a
prospective study. Materials and Methods : Forty patients admitted and
operated over a period of two years, were assigned to two groups:
laparascopic cholecystectomy (LC) (Group-I) or open cholecystectomy
(OC) (Group-II). Selection was based on: patientsâČ preference,
patientsâČ insistence, patientsâČ inability to afford the
laparoscopic procedure, lack of expertise or lack of facility in the
hospital for the laparoscopic procedure. The baseline characteristics
in terms of anesthetic protocol, fluid management, postoperative orders
and perioperative care were kept similar for both groups. Statistical
Analysis : SPSS v.11 was used for statistical computations. Results :
Baseline values of CRP in the OC and LC Groups were 7.9959 ±
5.57837 ”g/ml and 11.3948 ± 11.61055 ”g/ml respectively.
CRP values rose markedly during the intra- as well as the postoperative
periods till day 4 ( P < 0.001) in both the groups. Intragroup
variations were not significantly different from each other ( P >
0.05). No such trend was noticed for TNF-α levels under identical
conditions. Indeed, the TNF-α levels were 2.0304 ± 5.67384
pg/ml and 11.3408 ± 25.09385 pg/ml in the OC and LC groups
respectively. Intragroup changes were not significantly different from
each other ( P > 0.05). Percentage changes in CRP and TNF-α
were higher after OC in comparison to LC. Conclusions : The present
study did not record statistical differences in the levels of the two
markers (CRP, TNF-α) between the two groups. This reflects the
limited tissue trauma due to easy and simple visceral tissue dissection
in the two types of nondifficult surgery intraoperatively. However,
greater change ( P = 0.09) of TNF levels (30% vs. 1.9%) in the OC
group on the 4 th postoperative day represents the possibility of
greater immune modulation in the OC group postoperatively
Comparative assessment of TNF-\u3b1 and C-reactive protein in patients subjected to open instead of laparoscopic cholecystectomy
Background : C-reactive protein (CRP) and tumor necrosis factor-\u3b1
(TNF- \u3b1) are specific proteins modulated by the acute stress of
surgery. Various retrospective and prospective studies have
demonstrated subdued stress responses in laparoscopically operated
patients vis-\ue0-vis the conventional (open) method. Aim : To
assess the roles of TNF- \u3b1 and C-reactive protein levels as
tentative stress markers in correlating the extent of perioperative
immune modulation during open and laparoscopic cholecystectomy in a
subset of an Indian population. Setting and Design : This study is a
prospective study. Materials and Methods : Forty patients admitted and
operated over a period of two years, were assigned to two groups:
laparascopic cholecystectomy (LC) (Group-I) or open cholecystectomy
(OC) (Group-II). Selection was based on: patients\u2032 preference,
patients\u2032 insistence, patients\u2032 inability to afford the
laparoscopic procedure, lack of expertise or lack of facility in the
hospital for the laparoscopic procedure. The baseline characteristics
in terms of anesthetic protocol, fluid management, postoperative orders
and perioperative care were kept similar for both groups. Statistical
Analysis : SPSS v.11 was used for statistical computations. Results :
Baseline values of CRP in the OC and LC Groups were 7.9959 \ub1
5.57837 \ub5g/ml and 11.3948 \ub1 11.61055 \ub5g/ml respectively.
CRP values rose markedly during the intra- as well as the postoperative
periods till day 4 ( P < 0.001) in both the groups. Intragroup
variations were not significantly different from each other ( P >
0.05). No such trend was noticed for TNF-\u3b1 levels under identical
conditions. Indeed, the TNF-\u3b1 levels were 2.0304 \ub1 5.67384
pg/ml and 11.3408 \ub1 25.09385 pg/ml in the OC and LC groups
respectively. Intragroup changes were not significantly different from
each other ( P > 0.05). Percentage changes in CRP and TNF-\u3b1
were higher after OC in comparison to LC. Conclusions : The present
study did not record statistical differences in the levels of the two
markers (CRP, TNF-\u3b1) between the two groups. This reflects the
limited tissue trauma due to easy and simple visceral tissue dissection
in the two types of nondifficult surgery intraoperatively. However,
greater change ( P = 0.09) of TNF levels (30% vs. 1.9%) in the OC
group on the 4 th postoperative day represents the possibility of
greater immune modulation in the OC group postoperatively
Biofabricated Silver Nanoparticles Act as a Strong Fungicide against <i>Bipolaris sorokiniana</i> Causing Spot Blotch Disease in Wheat
<div><p>The present study is focused on the extracellular synthesis of silver nanoparticles (AgNPs) using culture supernatant of an agriculturally important bacterium, <i>Serratia</i> sp. BHU-S4 and demonstrates its effective application for the management of spot blotch disease in wheat. The biosynthesis of AgNPs by <i>Serratia</i> sp. BHU-S4 (denoted as bsAgNPs) was monitored by UVâvisible spectrum that showed the surface plasmon resonance (SPR) peak at 410 nm, an important characteristic of AgNPs. Furthermore, the structural, morphological, elemental, functional and thermal characterization of bsAgNPs was carried out using the X-ray diffraction (XRD), electron and atomic microscopies, energy dispersive X-ray (EDAX) spectrometer, FTIR spectroscopy and thermogravimetric analyzer (TGA), respectively. The bsAgNPs were spherical in shape with size range of âŒ10 to 20 nm. The XRD and EDAX analysis confirmed successful biosynthesis and crystalline nature of AgNPs. The bsAgNPs exhibited strong antifungal activity against <i>Bipolaris sorokiniana</i>, the spot blotch pathogen of wheat. Interestingly, 2, 4 and 10 ”g/ml concentrations of bsAgNPs accounted for complete inhibition of conidial germination, whereas in the absence of bsAgNPs, conidial germination was 100%. A detached leaf bioassay revealed prominent conidial germination on wheat leaves infected with <i>B. sorokiniana</i> conidial suspension alone, while the germination of conidia was totally inhibited when the leaves were treated with bsAgNPs. The results were further authenticated under green house conditions, where application of bsAgNPs significantly reduced <i>B. sorokiniana</i> infection in wheat plants. Histochemical staining revealed a significant role of bsAgNPs treatment in inducing lignin deposition in vascular bundles. In summary, our findings represent the efficient application of bsAgNPs in plant disease management, indicating the exciting possibilities of nanofungicide employing agriculturally important bacteria.</p></div
Biosynthesis of Stable Antioxidant ZnO Nanoparticles by <i>Pseudomonas aeruginosa</i> Rhamnolipids
<div><p>During the last several years, various chemical methods have been used for synthesis of a variety of metal nanoparticles. Most of these methods pose severe environmental problems and biological risks; therefore the present study reports a biological route for synthesis of zinc oxide nanoparticles using <i>Pseudomonas aeruginosa</i> rhamnolipids (RLs) (denoted as <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a>) and their antioxidant property. Formation of stable <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a> nanoparticles gave mostly spherical particles with a particle size ranging from 35 to 80 nm. The <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a> nanoparticles were characterized by UV-visible (UVâvis) spectroscopy, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and thermal gravimetric analysis. The UVâvis spectra presented a characteristic absorbance peak at âŒ360 nm for synthesized <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a> nanoparticles. The XRD spectrum showed that <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a> nanoparticles are crystalline in nature and have typical wurtzite type polycrystals. Antioxidant potential of <a href="mailto:RL@ZnO" target="_blank">RL@ZnO</a> nanoparticles was assessed through 2,2âdiphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and superoxide anion free radicals with varying concentration and time of the storage up to 15 months, while it was found to decline in bare ZnO nanoparticles. Similarly, the inhibitory effects on ÎČ-carotene oxidation and lipid peroxidation were also observed. These results elucidate the significance of <i>P</i>. <i>aeruginosa</i> RL as effective stabilizing agents to develop surface protective ZnO nanoparticles, which can be used as promising antioxidants in biological system.</p></div
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