283 research outputs found
GC-MS Analysis of Bio-Active Compounds in Aqueous Extract of Boerhaavia Diffusa, Euphorbia Hirta and Amaranthus Polygonoides
No full textMedicinal plants have had a crucial role in human culture and civilization. The present study deals with the Gas Chromatography Mass Spectroscopy analysis of Boerhaavia diffusa, Euphorbia hirta and Amaranthus polygonoides, which have various medicinal properties. The aim of this study was to investigate and characterize the chemical composition of the different crude aqueous extracts of these plant samples using PerkinElmer Gas Chromatography'Mass Spectrometry. Our results show that the compounds in the extract revealed by GC MS were the same as recorded in the National Institute of Standards and Technology NIST library. The identity and quantity of the measured active compounds was correlated with the expected therapeutic effects. The content of active principles was determined. The quantity of the active principles in the plants was also determined. R. Ezhilarasi | Dr. B. Senthilkumar | Dr. K. Devi "GC-MS Analysis of Bio-Active Compounds in Aqueous Extract of Boerhaavia Diffusa, Euphorbia Hirta and Amaranthus Polygonoides" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-1 , December 2019, URL: https://www.ijtsrd.com/papers/ijtsrd29436.pd
Design and analysis of peptide based nanoparticles
No full textViruses are naturally formed bionanoparticles (BNPs), ranging in size from 22-150 nm. Remarkably, small viruses are composed of one single protein chain folding into a capsid structure with icosahedral symmetry. The icosahedron is built up from 60 asymmetric units and is the largest closed shell in which every subunit is in an identical environment. It is characterized by 2-fold, 3-fold and 5-fold rotational symmetry axes. By superposition of different protein oligomerization domains onto the symmetry axes of the icosahedron, a nanoparticle with icosahedral symmetry can be designed. To test our concept, we have designed a peptide comprising a slightly modified form of a pentameric coiled-coil domain of cartilage oligomeric matrix protein (COMP) linked to a de novo designed trimeric coiled-coil domain as a single chain. These two different oligomeric domains were linked by two glycine residues to provide flexibility between them and were fixed in their relative orientation with an intramolecular disulfide bridge. Computer modeling predicted that such a design would result in an icosahedral peptide based nanoparticle with a diameter of 17 nm. We chemically synthesized the above designed peptide and performed refolding studies and biophysical characterization using analytical ultra centrifugation (AUC) and electron microscopy (EM), thereby showing the formation of icosahedral nanoparticles with a diameter of ~ 17 nm. Subsequently, we switched to recombinant expression of the designed peptide. Again, we performed refolding studies with the expressed peptide and biophysical characterization (AUC and EM), thereby showing the formation of icosahedral nanoparticles with a diameter of ~ 17 nm. In addition, we showed that during refolding, parameters such as ionic strength, pH of the refolding buffer and presence of glycerol influence the formation of icosahedral nanoparticles. Moreover, we observed icosahedral nanoparticles in conditions in which the formation of intramolecular disulfide bridges is not possible. This showed that even in the absence of intramolecular disulfide bridge the helices of the two different oligomeric domains like to be arranged close to each other, as this will favor the formation of icosahedral nanoparticles.
In parallel, we also modified the designed peptide to include charged residues at the
interface between the two oligomeric domains. The idea was to fix the relative orientation
between the two oligomeric domains through ionic interactions. The subsequent
expression, refolding studies and biophysical characterization showed the formation of
nanoparticles, but they were lacking icosahedral symmetry. This result showed that the
design has to be optimized further to obtain icosahedral nanoparticles.
Moreover, we wanted to study whether in our design principles oligomerization motifs
other than coiled-coils can be used to form icosahedral nanoparticles. Accordingly, we
used globular foldon domain as the trimerization domain and the COMP as the
pentamerization domain. The results showed the formation of nanoparticles, but they
were lacking icosahedral symmetry. In addition, in the above design we studied the effect
of linker region by increasing the liker region to four and six residues, but it did not help
in the formation of icosahedral nanoparticles. However, when the foldon domain
extended with the trimeric coiled-coil domain as a single trimerization domain and with
COMP as the penatmerization domain, we observed icosahedral nanoparticles.
Viruses are known for their induction of strong antibody (B-cell) mediated immune
response in the host even against the self-antigens. This property is conferred by the
repetitive arrangement of the antigens on their surface. Peptide based nanoparticles have
similar properties to viruses, such as self-assembly and most importantly the repetitive
arrangement of subunits (peptide based nanoparticles are composed of 60 identical
monomeric chains). Therefore, we wanted to use our system as a ‘repetitive antigen
display carrier’ in vaccination, as an alternative to viral and viral based platforms such as
virus like particles (VLPs). To this end, and in order to understand the effect of our
nanoparticle size on immune response, we built different constructs displaying the pilin
epitope of Pseudomonas pathogen at their C-terminus. Computer modeling indicated that
these constructs would form icosahedral nanoparticles of three sizes: small (18 nm),
medium (23 nm) and large (29 nm). From the refolding studies, we observed mostly
aggregation and precipitation of the nanoparticles.
This effect presumably due to interparticle cross-linking, by the cysteine residues of
pilin epitope which are present at the periphery of nanoparticles, as we observed
aggregation of small size icosahedral nanoparticles upon changing from reducing to
oxidizing condition. Immunization results, because of the aggregation and precipitation
behavior of nanoparticles, showed poor immune response. However, the immunization
results showed that our nanoparticles present the attached epitope in their native form, as
we observed binding against native pilin protein. Moreover, immunization results from
our laboratory using medium size nanoparticles displaying Salmonella epitope D2
showed promising results, as we got antibody titer values which were well comparable to
the values obtained with VLPs. This places our system alongside with VLPs, which are in
clinical trials as a carrier in vaccination
Entomopathogenic Fungi for the Management of Calopepla leayana on Gmelina arborea
No full textEntomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae were isolated and identified as natural pathogens of Calopepla leayana. Both the species of fungi were effective against the larval and adult stages of C. leayana causing white and green muscardine diseases respectively. It was also found that B. bassiana was more pathogenic to the pest as compared to M. anisopliae. The susceptibility of larvae and adults was negatively associated with the age and positively associated with the fungal spore concentration. In all the stages from I instar to adult, the highest mortality was observed in 10% of 1x109 spores/ml concentration of B. bassiana among 1, 2.5, 5 & 10% of 1x109 spores/ml concentration. It was also reflected in probit analysis that the concentration of spores required to kill fifty percent of the population was ranges from 0.09% to 5.98% of 1x109 spores/ml concentration of B. bassiana and 1.02% to 9.72% of 1x109 spores/ml concentration of M. anisopliae. The larvae of I instar have shown highest mortality, which gradually decreased with the increase in age or decrease in the concentration of fungal spores. Mass production of B. bassiana using different substrates was attempted to harvest ample amount of spores. This study revealed that spore production was directly proportional to the mycelial weight and incubation period. From the seven substrates tested, wheat flour was identified as one of the suitable substrates for the mass production of B. bassiana. A field trial was conducted to test their efficacy under field conditions. 72-93% mortality was observed in field conditions.-----------------------------------------------------------------------------------------------------Division of Bioprospecting, Institute of Forest Genetics and Tree Breeding, Coimbatore-641002, Tamilnadu, India*Corresponding author, Email: [email protected] This Article As: N. Senthilkumar and S. Murugesan. 2010. Entomopathogenic Fungi for the Management of Calopepla leayana on Gmelina arborea. J. Ecobiotechnol. 2(3): 01-0
Comparative Study on Extubation Stress Response with Endotracheal Tube, Laryngeal Mask Airway and Replacement of Endotracheal Tube with Laryngeal Mask Airway
No full textINTRODUCTION:
General anaesthesia with endotracheal intubation and intermittent positive pressure ventilation is frequently performed in the practice of anaesthesia. Endotracheal intubation (insertion of ETT into the trachea) and extubation (trans laryngeal removal of ETT) are a part of general anaesthesia and both are associated with hemodynamic responses.
Endotracheal extubation is associated with haemodynamic changes due to reflex sympathetic discharge and cough caused by epipharyngeal and laryngopharyngeal stimulation. Increase in sympathoadrenal activity results in tachycardia, hypertension and arrhythmias. This increase in heart rate and blood pressure are usually for a short period of time, variable and unpredictable. This response is more harmful to patients with systemic hypertension, coronary artery disease or cerebrovascular diseases. Therefore haemodynamic response to tracheal extubation has always been a challenge to anaesthesiologist.
Many pharmacological methods like administration of lignocaine, verapamil, diltiazem before extubation have been studied, but none of them proved to completely abolish extubation stress response.
Non-pharmacological methods like extubation of the patient in deep plane with spontaneous respiration have been studied to reduce the hemodynamic stress response and cough during extubation. Major disadvantage of these methods is that they produce cardiovascular depression and inadequate upper airway reflexes.
The laryngeal mask airway is a supraglottic airway device. It is a good alternative to endotracheal tube and face mask for spontaneous or positive pressure ventilation. LMA makes intubation and extubation less stimulating than endotracheal tube. So we replaced ETT with LMA at the end of the procedure and studied extubation stress responses.
Hence the present study was undertaken to compare the extubation stress response with endotracheal tube, laryngeal mask airway and replacement of endotracheal tube with laryngeal mask airway
AIM OF THE STUDY:
The aim of the study was to compare the extubation stress response with endotracheal tube, laryngeal mask airway and replacement of endotracheal tube with laryngeal mask airway, in terms of hemodynamic stress responses and respiratory complications during extubation.
MATERIALS:
The materials needed for the study includes,
1. Drugs for general anesthesia:
a. Injection Glycopyrollate,
b. Injection Midazolam,
c. Injection Fentanyl,
d. Injection Propofol,
e. Injection Suxamethonium,
f. Injection Atracurium,
g. Injection Neostigmine.
2. Appropriate size face masks,
3. Appropriate size laryngoscopes,
4. Appropriate size Endotracheal tubes,
5. Laryngeal mask airway size = 3 & 4,
6. Working suction apparatus,
7. Monitors – Pulse oximeter, ECG, NIBP,
8. Intravenous fluids and intravenous cannula,
9. Circle system,
10. All emergency drugs.
STUDY METHODS:
This study was a randomized comparative study conducted in
Government Stanley hospital, Chennai during the period of March 2012 to August 2012. After obtaining clearance from the Institutional Ethical Committee of the Stanley Medical College, Chennai, a pilot study was done to define study population and to decide on inclusion and exclusion criteria.
A target population of 90 patients was decided. After proper
screening of patients for the inclusion and exclusion criteria, they were informed about the purpose of the study and the procedure on the day before surgery. A written informed consent was obtained from the patient.
CRITERIA FOR SELECTION:
Inclusion Criteria:
1. Age Group 20-60 years,
2. ASA I or ASA II,
3. Elective surgeries done under general anaesthesia.
Exclusion Criteria:
1. Obesity,
2. Craniofacial anomalies,
3. Hyperreactive airway.
The study population were randomly assigned to three Groups
labeled as A, B and C. Each Group was allotted 30 patients.
Randomization was achieved by allotting lots with alphabets A, B and C. Patients with lot A assigned to Group A. Those with lot Bassigned to Group B. Those patients with lot C assigned to Group C.
Statistical Analysis:
The data were analysed using SPSS (Statistical Package for Social Science) Version 16.01. The data collected were scored and analyzed, Continues variables were presented as mean with Standard deviation (Sd) and categorical variables were presented as frequency and percentages.
Student t-test and Analysis of Variance (Anova) were used for testing the significance of all the variables (Mean &Sd). Chi-square test was used to compare proportions. All the Statistical results were considered significant at P value < 0.05.
SUMMARY:
The study “ Comparative Study on Extubation Stress Response with Endotracheal Tube, Laryngeal Mask Airway and Replacement of Endotracheal Tube with Laryngeal Mask Airway” was carried out at Stanley Medical College and Hospital Chennai , from March 2012 To August 2012.
The Groups were comparable for Age, Sex, Weight.
Our observations were:
1. There was a marked rise in Heart rate at 1 , 3 , 5 and 10 minutes after ETT extubation (Group A), when compared to removal of
LMA (Group B) and replacing ETT with LMA before extubation
(Group C).
2. There was a marked rise in Mean arterial blood pressure at 1, 3, 5 and 10 minutes after ETT extubation (Group A) , when compared to removal of LMA (Group B) and replacing ETT with LMA before
extubation (Group C).
3. Increased incidence of cough ,sorethroat and hoarseness of voice after ETT extubation (Group A), when compared to removal of
LMA (Group B) and replacing ETT with LMA before extubation
(Group C).
4. There was no significant difference in HR and MAP values at baseline, 5 minutes before reversal and at 1 , 3, 5 and 10 minutes after removal of LMA between LMA (Group B) and ETT replacing
LMA (Group C).
CONCLUSION:
Many pharmacological and non-pharmacological methods have
been used to attenuate hemodynamic stress response and cough during extubation,but none are satisfactory.
Replacement of Endotracheal tube with Laryngeal Mask Airway
20 minutes before the end of procedure is a simple and effective method to attenuate extubation stress response with endotracheal tube.
It is ideal to have an Endotracheal tube to maintain the airway for prolonged surgical procedures requiring general anaesthesiawith positive pressure ventilationand by replacing Endotracheal tube with Laryngeal Mask Airway at the end of prolonged surgeries we can have the combined advantage of both Endotracheal tube and smoother emergence due to Laryngeal Mask Airway
Six Sigma Modified Quick Switching Variables Sampling System of type SSMQSVSS (nT, nN; k) Indexed by Six Sigma Quality Levels
No full textIT EMPLOYEE WANTS FROM THEIR EMPLOYER VIS-À-VIS THE EMPLOYER'S PRODUCTIVITY EXPECTATION IN TODAY'S COVID-19 CONTEXT- A CASE STUDY ABOUT THE IT SECTOR'S ONGOING ATTRITION CHALLENGES
No full textCovid 19 pandemic shook the world in late December 2019 and took away more than two and a half years in a modern civilized society. IT companies that boosted the Golden BCP standards implementation in the organization were complete whitewash. Businesses, people, Infra, and Government machinery had no choice but to pump money into the employee to save employees from the competition and sustain committed deliverables. Thankfully, IT company leaders put the act together bravely and put the recovery process by introducing Work from Home (WFH) immediately and arranged IT hardware infra at the doorstep of employees with the flexibility to operate from anywhere. As per KPMG, IT Companies spent around US250 bn in 2021, which is 3.4% against 1.7% of the average investment required to run an operation. The objective of the case study is to analyze the three complex situations that arise during the Covid 19
a. High attrition, b. High investment from employer, c. Low productivity challenges. IT companies are on the path of business recovery, whereas stress continues on employee expectations vs. employee productivity.</p
Synthesis of N-Heterocyclic Carbene Stabilized Catecholatoborenium Cations by Ligand Substitution
No full textLigand substitution is not a common procedure for the preparation of different borenium cations. This work demonstrates that the chloride ligands of several NHC-stabilized dichloroborenium cations [NHC·BCl2][X] (NHC = (R′C)2(NR)2C; 1, R = iPr, R′ = H; 2, R = iPr, R′ = Me; 3, R = tBu, R′ = H; X = AlCl4, B(3,5-Cl2-C6H3)4) could be replaced with a catecholato moiety to produce [NHC·Bcat][X]. According to single-crystal X-ray analyses this particular ligand exchange enhanced the Lewis acidity of the target borocations with respect to the dichloro precursors.ASTAR (Agency for Sci., Tech. and Research, S’pore)Accepted versio
Additions and corrections: Nano a-NiMoO4 as new electrode for electrochemical supercapacitors
No full textTwo of the author names are incorrectly written, showing the surname as the first name, and the first name as the surname. The correct names are Danielle Meyrick and Manickam Minaksh
C–F Bond Activation by Transient Phosphenium Dications
No full textC–F bond cleavage by transient
phosphorus(III)-based dications [RP(C(PPh<sub>3</sub>)<sub>2</sub>)]<sup>2+</sup> (<b>4a</b><sup><b>2+</b></sup>, R = Ph; <b>4b</b><sup><b>2+</b></sup>, R = 4-F-Ph) is reported. These
dications were generated by reaction of the corresponding monocationic
precursors with excess Na[BAr<sub>4</sub><sup>Cl</sup>]. Evidence
for the existence of transient dicationic species was obtained by
trapping the dication <b>4a</b><sup><b>2+</b></sup> with
PMe<sub>3</sub>. According to theoretical analysis, the low-lying
lowest unoccupied molecular orbitals of these species were responsible
for the observed activation of C–F bonds
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