47 results on '"Ilango, S."'
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2. Crystallization kinetics and role of stress in Al induced layer exchange crystallization process of amorphous SiGe thin film on glass
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Sain, Twisha, Singh, Ch. Kishan, Ilango, S., and Mathews, T.
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Condensed Matter - Materials Science - Abstract
The present study reports Al induced crystallization (AIC) of amorphous (a)-SiGe in Al-Ge-Si ternary system at low temperature ~ 350 degree C. In addition to crystallization, the isothermal annealing of a-SiGe/AlOx/Al/corning-glass (CG) structure was found to be accompanied by an Al induced layer exchange (ALILE) phenomenon. The evolution of residual stress in the Al layer during isothermal annealing is evaluated using X-ray diffraction based technique to ascertain the role of stress in the ALILE process. A corroboration of the stress with the growth kinetics, analyzed using Avrami theory of phase transformation gives a comprehensive understanding of the ALILE crystallization process in this system. The grown polycrystalline SiGe thin film is a potential candidate for novel technological applications in semiconductor devices., Comment: 24 pages, 11 figures
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- 2019
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3. Si and N - vacancy color centers in discrete diamond nanoparticles: Raman and fluorescence spectroscopic studies
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Ganesan, K., Ajikumar, P. K., Ilango, S., Mangamma, G., and Dhara, S.
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Condensed Matter - Materials Science - Abstract
The present study reports on an innovative method to prepare discrete diamond nanoparticles or nanodiamonds (NDs) with high structural and optical quality through top-down approach by controlled oxidation of pre-synthesized nanocrystalline diamond (NCD) film. These NDs are studied for their structural and optical properties using atomic force microscopy (AFM), Raman and fluorescence (FL) spectroscopy. While AFM analysis confirms uniform distribution of discrete NDs with different sizes varying from a few tens of nanometers to about a micron, spectroscopic investigations reveal the presence of impurity - vacancy related color centers exhibiting FL at 637 and 738 nm as a function of particle size. In addition, an intense emission originating from vacancy centers associated with N and Si (SiV-) is observed for all NDs at the temperature close to liquid nitrogen. A detailed spectral analysis is carried out on the structural defects in these NDs. The full width at half maximum of diamond Raman band ( ~ 1332 cm-1) is found to be as narrow as 1.5 cm-1 which reveals the superior structural quality of these NDs. Further, mapping of diamond Raman and FL spectra of SiV- confirm the uniform distribution of NDs throughout the substrate. The narrow line widths and a minimal shift in peak positions of Raman and FL spectra endorse this aspect., Comment: 30 pages, 5 figures, 3 Tables
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- 2019
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4. A Survey on Training Issues in Chili Leaf Diseases Identification Using Deep Learning Techniques
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Kanaparthi, Kantha Raju and Sudhakar Ilango, S.
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- 2023
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5. In-situ formation of SiGe alloy by electron beam evaporation and the effect of post deposition annealing on the energy band gap
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Tah, Twisha, Singh, Ch. Kishan, Amirthapandian, S., Madapu, K. K., Sagdeo, A., Ilango, S., Mathews, T., and Dash, S.
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Condensed Matter - Materials Science - Abstract
We report the synthesis of polycrystalline (poly)-SiGe alloy thin films through solid state reaction of Si/Ge multilayer thin films on Si and glass substrates at low temperature of 500 {\deg}C. The pristine thin film was deposited using electron beam evaporation with optimized in-situ substrate heating. Our results show the co-existence of amorphous Si (a-Si) phase along with the poly-SiGe phase in the pristine thin film. The a-Si phase was found to subsume into the SiGe phase upon post deposition annealing in the temperature range from 600 to 800 {\deg}C. Additionally, dual energy band gaps could be observed in the optical properties of the annealed poly-SiGe thin films. The stoichiometric evolution of the pristine thin film and its subsequent effect on the band gap upon annealing are discussed on the basis of diffusion characteristics of Si in poly-SiGe., Comment: 18 pages, 9 figures, 2 tables
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- 2017
6. Flipping growth orientation of nanographitic structures by plasma enhanced chemical vapor deposition
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Ghosh, Subrata, Ganesan, K., Polaki, S. R., Ilango, S., Amirthapandian, S., Dhara, S., Kamruddin, M., and Tyagi, A. K.
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Condensed Matter - Materials Science - Abstract
Nanographitic structures (NGSs) with multitude of morphological features are grown on SiO2/Si substrates by electron cyclotron resonance - plasma enhanced chemical vapor deposition (ECR-PECVD). CH4 is used as source gas with Ar and H2 as dilutants. Field emission scanning electron microscopy, high resolution transmission electron microscopy (HRTEM) and Raman spectroscopy are used to study the structural and morphological features of the grown films. Herein, we demonstrate, how the morphology can be tuned from planar to vertical structure using single control parameter namely, dilution of CH4 with Ar and/or H2. Our results show that the competitive growth and etching processes dictate the morphology of the NGSs. While Ar-rich composition favors vertically oriented graphene nanosheets, H2-rich composition aids growth of planar films. Raman analysis reveals dilution of CH4 with either Ar or H2 or in combination helps to improve the structural quality of the films. Line shape analysis of Raman 2D band shows nearly symmetric Lorentzian profile which confirms the turbostratic nature of the grown NGSs. Further, this aspect is elucidated by HRTEM studies by observing elliptical diffraction pattern. Based on these experiments, a comprehensive understanding is obtained on the growth and structural properties of NGSs grown over a wide range of feedstock compositions., Comment: 19 pages, 8 figures, 1 table
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- 2017
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7. Deep Learning Methods for Detecting Chilli Pests: A Novel Performance Analysis
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Kanaparthi, Kantha Raju, primary and Ilango, S. Sudhakar, additional
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- 2024
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8. A comparative study on defect estimation using XPS and Raman spectroscopy in few layer nanographitic structures
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Ganesan, K., Ghosh, Subrata, Krishna, Nanda Gopala, Ilango, S., Kamruddin, M., and Tyagi, A. K.
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Condensed Matter - Materials Science - Abstract
Defects in planar and vertically oriented nanographitic structures (NGSs) synthesized by plasma enhanced chemical vapor deposition (PECVD) has been investigated using Raman and X-ray photoelectron spectroscopy. While Raman spectra reveal the dominance of vacancy and boundary type defects respectively in vertical and planar NGSs, XPS provides additional information on vacancy related defect peaks at C 1s spectrum that originate from non-conjugated carbon atoms in hexagonal lattice. Although an excellent correlation prevails between these two techniques, our results show that estimation of surface defects by XPS is more accurate than Raman analysis. Nuances of these techniques are discussed in the context of assessing defects in nanographitic structures., Comment: 21 pages, 5 figures, 2 tables
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- 2016
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9. XPS studies on AlN thin films grown by ion beam sputtering in reactive assistance of N+/N2+ ions: Substrate temperature induced compositional variations
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Sharma, Neha, Ilango, S., Dash, S., and Tyagi, A. K.
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Condensed Matter - Materials Science - Abstract
We report on an XPS study of AlN thin films grown on Si(100) substrates by ion beam sputter deposition (IBSD) in reactive assistance of N+/N2+ ions to unravel the compositional variation of their surface when deposited at different substrate temperatures. The temperature of the substrate was varied as room temperature (RT), 100oC and 500oC. The binding energy of Al-2p, N-1s and O-1s core electrons indicate the formation of 2H polytypoid of AlN. The increase in concentration of AlN with substrate temperature during deposition is elucidated through detailed analysis with calculated elemental atomic concentrations (at. %) of all possible phases at the film surface. Our results show that predominate formation of AlN as high as 74 at. % is achievable using substrate temperature as the only process parameter. This high fraction of AlN in thin film surface composition is remarkable when compared to other growth techniques. Also, the formation of other phases is established based on their elemental concentrations., Comment: 13 pages, 6 figures, 2 tables, submitted to the journal "Thin Solid Films"
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- 2015
10. Optical band gap and associated band-tails in nanocrystalline AlN thin films grown by reactive IBSD at different substrate temperatures
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Sharma, Neha, Sharma, Shilpam, Prabakar, K., Amirthapandian, S., Ilango, S., Dash, S., and Tyagi, A. K.
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Condensed Matter - Materials Science - Abstract
AlN thin films have been grown on Si (100) substrates by reactive ion beam sputter deposition (IBSD) at different substrate temperatures varying from room temperature (RT) to 500oC. Substrate temperature induced microstructural transition from amorphous at RT, nanocrystalline at 300oC to microcrystalline at 400oC has been observed by Transmission Electron Microscopy (TEM). Average surface roughness (Ra) and morphology has been explored by using Atomic Force Microscopy (AFM). UV-VIS spectrophotometry has been employed to probe the substrate temperature induced changes in optical band-gap (Eg) of grown thin films in reflectance mode. It was found that Eg was increased from 5.08 to 5.21 eV as substrate temperature was increased from RT to 500oC. Urbach energy tail (Eu) along with weak absorption tail (WAT) energy (Et) have been estimated to account for the optical disorder which was found to decrease with associated increase in Eg., Comment: 22 pages, 6 figures, 2tables
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- 2015
11. Growth Kinetic studies of ion beam sputtered AlN-thin films: Effect of reactive assistance of nitrogen plasma
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Sharma, Neha, Prabhakar, K., Ilango, S., Dash, S., and Tyagi, A. K.
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Condensed Matter - Materials Science - Abstract
Reactive dual ion beam sputter deposition of AlN thin films was carried out for the analysis of surface growth characteristics by Atomic Force Microscopy. The variation of roughness as a function of deposition time was analysed by Dynamic Scaling Theory (DST). Two distinct exponents, static and dynamic were used to unravel the film growth characteristics. As the deposition time increased, static scaling exponent decreased gradually and substrate surface coverage was increased which is indicated by a decrease in critical length Lc. The rms roughness of the film was increased from 1.99 to 3.42 nm as the deposition time was increased from 3 minutes to 15 minutes. Dynamic scaling exponent was found to be 0.36. During the growth, surface diffusion (n = 4) becomes the major roughening phenomenon while Bulk diffusion (n = 3) turns into the dominating smoothening phenomenon., Comment: 10 pages, 8 figures
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- 2014
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12. Students’ emotional well-being and religiosity during the COVID-19 pandemic- an international study in 7 countries
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Karakula, K. H., primary, Forma, A., additional, Sitarz, R., additional, Baj, J., additional, Juchnowicz, D., additional, Bogucki, J., additional, Tuszyńska-Bogucka, W., additional, Tee, M. L., additional, Tee, C. A., additional, Ly-Uson, J. T., additional, Islam, M. S., additional, Sikder, M. T., additional, El-Monshed, A. H., additional, Loutfy, A., additional, Hussain Qureshi, M. F., additional, Abbas, M., additional, Taseen, S., additional, Lakhani, M., additional, Jayakumar, S., additional, Ilango, S., additional, Kumar, S., additional, Ruiz-Chow, Á. A., additional, Iturbide, A., additional, González-Mille, D. D., additional, and Karakula-Juchnowicz, H., additional
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- 2023
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13. Predictors of breast cancer among women attending a tertiary care hospital in Puducherry-A case-control study
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Vinayagamoorthy Venugopal, Ilango S Parthasarathy, P Thrivikrama Rao, and Ashwyn Anand
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medicine.medical_specialty ,business.industry ,Incidence (epidemiology) ,Public health ,Case-control study ,Developing country ,Tertiary care hospital ,medicine.disease ,Tertiary care ,Breast cancer ,Quality of life ,Family medicine ,Medicine ,business - Abstract
Introduction: The incidence of breast cancer is increasing in developing countries over decades. Breast cancer is a public health problem in India. Identifying the risk factors helps to reduce the incidence and improve quality of life of people in future. Method: A hospital based case control study was conducted among all the breast cancer cases newly diagnosed in a tertiary care teaching hospital in Puducherry. 40 cases of breast cancer were paired with age matched controls from the same hospital (ratio 1:2) with a total of 120 study participants. Data were collected by interviewing the participants using a pre tested structured questionnaire. Analysis was done using SPSS version 24.0 Results: Age group of participants ranged from 35-69 years. Age group of 46-55 years [OR-3.4; 95% CI: 1.1-11.2], homemaker [OR-0.4; 95% CI: 0.2-0.9], Early menarche
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- 2020
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14. Synthesis and Characterization of Bio-Based Polyurethane from Benzoylated Cashewnut Husk Tannins
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Sunija, A J, Ilango, S Siva, and Kumar, K P Vinod
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- 2014
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15. Prevalence of fluorosis and identification of fluoride endemic areas in Manur block of Tirunelveli District, Tamil Nadu, South India
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Gopalakrishnan, Subarayan Bothi, Viswanathan, Gopalan, and Siva Ilango, S.
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- 2012
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16. Extreme heat episodes, wildfires, and risk of preterm delivery in California, 2005-2013
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Ilango S, Weaver M, and Benmarhnia T
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Extreme heat ,Global and Planetary Change ,medicine.medical_specialty ,Epidemiology ,business.industry ,Health, Toxicology and Mutagenesis ,Emergency medicine ,Public Health, Environmental and Occupational Health ,medicine ,business ,Pollution ,Preterm delivery - Published
- 2019
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17. Si and N - Vacancy color centers in discrete diamond nanoparticles: Raman and fluorescence spectroscopic studies
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Ganesan, K., primary, Ajikumar, P.K., additional, Ilango, S., additional, Mangamma, G., additional, and Dhara, S., additional
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- 2019
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18. Is renal biopsy always necessary to start immunosuppressive therapy in lupus nephritis?
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Chelliah, Vasudevan, primary, Balaraman, V, additional, Ilango, S, additional, Ramesh, S, additional, Bhaba, VKannan, additional, and Shivakumar, D, additional
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- 2017
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19. A cross-sectional study of renal donors
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Shivakumar, D., primary, Abeesh, P., additional, Vasudevan, C., additional, Ilango, S., additional, and Balaraman, V., additional
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- 2015
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20. 1-Formyl-r-2,c-6-bis(4-methoxyphenyl)-t-3,t-5-dimethylpiperidin-4-one
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Kavitha, T., primary, Sakthivel, P., additional, Ponnuswamy, S., additional, Ilango, S. S., additional, and Ponnuswamy, M. N., additional
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- 2009
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21. 3,3-Dimethyl-cis-2,6-di-p-tolylpiperidin-4-one
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Gayathri, P., primary, Ilango, S. S., additional, Ponnuswamy, S., additional, Thiruvalluvar, A., additional, and Butcher, R. J., additional
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- 2009
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22. 2,2,4-Trimethyl-5-(4-tolylsulfonyl)-2,3,4,5-tetrahydro-1H-1,5-benzodiazepine
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Ravichandran, K., primary, Sathiyaraj, K., additional, Ilango, S. S., additional, Ponnuswamy, S., additional, and Ponnuswamy, M. N., additional
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- 2009
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23. r-2,c-6-Bis(4-chlorophenyl)-c-3,t-3-dimethylpiperidin-4-one
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Ilango, S. S., primary, Ponnuswamy, S., additional, Gayathri, P., additional, Thiruvalluvar, A., additional, and Butcher, R. J., additional
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- 2008
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24. Adsorption of Cr(VI) onto Activated Carbons Prepared from Indigenous Materials
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Karthikeyan, G., primary and Ilango, S. Siva, additional
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- 2008
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25. Adsorption of Cr(VI) onto Activated Carbons Prepared from Indigenous Materials
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Karthikeyan, G. and Siva Ilango, S.
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The adsorption of chromium(VI) on activated carbons prepared from low cost materials has been studied by batch process. The influences of various parameters like contact time, dosage, pH, pHzpc and co-ions were experimentally verified. The adsorption of Cr(VI) is maximum at strongly acidic medium (pH 3). Adsorption is explained using Langmuir and Freundlich isotherms with help of chi-square analysis. Thermodynamic parameters like ΔG°, ΔH° and ΔS° were calculated to understand the nature of adsorption. The surface morphology of the three activated carbons before and after metal sorption was verified using scanning electron microscope (SEM) and X-ray diffraction studies (XRD).
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- 2008
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26. Dengue fever caused by dengue virus serotype - 3 (subtype-III) in a rural area of Madurai district, Tamil Nadu.
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Paramasivan, R., Dhananjeyan, K. J., Leo, S. Victor Jerald, Muniaraj, M., Thenmozhi, V., Rajendran, R., Tewari, S. C., Arunachalam, N., Varatharaj, M., Victor, T. John, Charles, Janshi, Ilango, S., and Tyagi, B. K.
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LETTERS to the editor , *DENGUE viruses - Abstract
A letter to the editor is presented about a study on the role of the dengue virus serotype 3 in the prevalence of dengue fever in Madurai district, Tamil Nadu, India.
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- 2010
27. Assessment of the Anterior Loop and Pattern of Entry of Mental Nerve Into the Mental Foramen: A Radiographic Study of Panoramic Images.
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Thiruvenkata Krishnan D, Joylin K, I P, M K, Hearty Deepak J, Ilango S, Hamad KA, Shanab H, Salama MH, and Jayakumar S
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Introduction: The precise location of the mental foramina is an essential landmark in planning the position of dental implants in the anterior mandible. Injury to inferior alveolar nerve during anterior mandibular implant surgery causes altered sensation which greatly affects patient satisfaction., Methods: In this study, we assessed the prevalence of anterior loop of mental nerve and the pattern of entry of mental nerve into the mental foramen. Three hundred panoramic radiographs (600 hemimandibles) obtained from records maintained in the Department of Oral Medicine and Radiology were randomly selected for the study. The radiographs were evaluated by two independent observers for the pattern of entry of mental nerve into the mental foramen on either side of the mandible and for the presence or absence of anterior loop of mental nerve., Results: The most prevalent pattern of mental nerve observed was Straight pattern which totals to 67.5% followed by Anterior loop pattern (18.8%) and then the Perpendicular pattern (13.7%). There was no significant association between the gender and subtypes of looping pattern on the left and right side and a highly significant association between the side of the mandible and loop pattern was observed by Chi square test., Conclusion: The Anterior loop pattern of mental nerve has been found in 18.8% of the population suggesting to accurate planning with three-dimensional imaging techniques to avoid injury to mental nerve during dental implant placement and other surgical procedure involving the interforaminal region of the mandible., Competing Interests: The authors have declared financial relationships, which are detailed in the next section., (Copyright © 2024, Thiruvenkata Krishnan et al.)
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- 2024
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28. Management of Complex Crown Fractures: A Case Series.
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Lakshmaiah D, Sr V, Ilango S, Sakthi N, and Ps S
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Maxillary teeth are most vulnerable to fracture due to trauma. An effective treatment plan for an anterior teeth fracture not only improves function and appearance but also benefits the patient psychologically. The reattachment of the fragmented tooth is one of the best treatment methods for such condition. It is considered as a better treatment option because it is uncomplicated, aesthetic, and preserves the dental structure. To achieve a positive prognosis, patient cooperation and awareness about the treatment are essential. This article includes three case reports that illustrate the management of complex maxillary anterior teeth fractures wherein the reattachment of the fractured tooth segments was undertaken., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Lakshmaiah et al.)
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- 2023
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29. Comparative Evaluation of Retention of Fiber Posts in Different Dentin Regions Using Various Bonding Techniques: An In Vitro Study.
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Thanikachalam Y, Kadandale S, Ilango S, Parthasarathy R, Vishwanath S, and Srinivasan S
- Abstract
Aim This study aims to evaluate the retention of fiber posts in the coronal, middle, and apical dentin regions with various bonding techniques by using fifth, sixth, and eighth-generation bonding agents and self-etch adhesive cement. Materials and methods For this study, 96 freshly extracted human incisors with straight roots were selected. Endodontic treatment of the specimens was performed. The post spaces were created immediately after obturation and the posts were luted with three different bonding agents and self-adhesive resin cement and the specimens were divided into four groups. Approximately 3 mm thick sections were made from different dentin regions of the post space and were tested for three subgroups: Subgroup I: Coronal, Subgroup II: Middle, Subgroup III: Apical. The specimens were tested on a universal testing machine. Results Statistical analysis was done using one-way analysis of variance (ANOVA) and Tukey's post hoc test using SPSS software version 17.0 (SPSS Inc., Chicago ). The intra-group comparison showed that the bond strength was more in the fifth-generation bonding agent (Cervical- 8.2574± 1.49034, Middle- 11.4800± 2.59938, Apical- 14.7108±1.82931), followed by the sixth (Cervical- 9.102± 2.76119, Middle-9.3152±2.11585, Apical- 12.9478±4.69404) and eighth-generation bonding systems (Cervical- 9.0938±2.77537, Middle- 7.1585±1.97601, Apical- 9.3726±0.73720) and the self-etch adhesive dental resin cement (Cervical- 5.1004±2.17389, Middle- 4.1574±1.28664, Apical-7.8884±1.90078). The inter-group comparison showed that the bond strength was higher in the fifth-generation bonding agent followed by sixth-generation, eighth-generation, and self-adhesive resin cement. Conclusion The present study reveals that the highest push-out bond strengths were obtained in apical sections followed by the middle and cervical areas. The bond strength was higher when using the fifth-generation bonding agent followed by the sixth, eighth, and self-adhesive resin cement. Despite many advancements, the fifth-generation bonding agent still showed superior retention in different dentin regions among various other bonding techniques., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Thanikachalam et al.)
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- 2023
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30. Green Synthesized Silver Nanoparticle-Loaded Liposome-Based Nanoarchitectonics for Cancer Management: In Vitro Drug Release Analysis.
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Jayachandran P, Ilango S, Suseela V, Nirmaladevi R, Shaik MR, Khan M, Khan M, and Shaik B
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Silver nanoparticles act as antitumor agents because of their antiproliferative and apoptosis-inducing properties. The present study aims to develop silver nanoparticle-loaded liposomes for the effective management of cancer. Silver nanoparticle-encapsulated liposomes were prepared using the thin-film hydration method coupled with sonication. The prepared liposomes were characterized by DLS (Dynamic Light Scattering analysis), FESEM (Field Emission Scanning Electron Microscope), and FTIR (Fourier Transform Infrared spectroscopy). The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method and the drug release profile was validated using various mathematical models. A high encapsulation efficiency of silver nanoparticle-loaded liposome was observed (82.25%). A particle size and polydispersity index of 172.1 nm and 0.381, respectively, and the zeta potential of -21.5 mV were recorded. FESEM analysis revealed spherical-shaped nanoparticles in the size range of 80-97 nm. The in vitro drug release profile of the silver nanoparticle-loaded liposomes was carried out using the dialysis bag method in three different pHs: pH 5.5, pH 6.8, and pH 7.4. A high silver nanoparticle release was observed in pH 5.5 which corresponds to the mature endosomes of tumor cells; 73.32 ± 0.68% nanoparticle was released at 72 h in pH 5.5. Among the various mathematical models analyzed, the Higuchi model was the best-fitted model as there is the highest value of the correlation coefficient which confirms that the drug release follows the diffusion-controlled process. From the Korsmeyer-Peppas model, it was confirmed that the drug release is based on anomalous non-Fickian diffusion. The results indicate that the silver nanoparticle-loaded liposomes can be used as an efficient drug delivery carrier to target cancer cells of various types.
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- 2023
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31. To Vaccinate or Not to Vaccinate-Reasons of Willingness and Reluctance of Students against SARS-CoV-2 Vaccination-An International Experience.
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Sitarz R, Forma A, Karakuła K, Juchnowicz D, Baj J, Bogucki J, Rog J, Tee ML, Tee CA, Ly-Uson JT, Islam MS, Sikder MT, El-Monshed AH, Loutfy A, Qureshi MFH, Abbas M, Taseen S, Lakhani M, Wang C, Wan X, Tan Y, Pan R, Ho R, Jayakumar S, Ilango S, Kumar S, Ruiz-Chow ÁA, Iturbide A, González-Mille DD, Doan LP, and Karakuła-Juchnowicz H
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- Humans, Adolescent, Young Adult, Adult, COVID-19 Vaccines, Cross-Sectional Studies, Health Knowledge, Attitudes, Practice, Vaccination psychology, Students psychology, SARS-CoV-2, COVID-19 epidemiology, COVID-19 prevention & control
- Abstract
Despite the vaccine against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) being reported to be safe and effective, the unwillingness to vaccinate and doubts are still common. The aim of this international study was to assess the major reasons for the unwillingness to vaccinate in a group of students from Poland (n = 1202), Bangladesh (n = 1586), India (n = 484), Mexico (n = 234), Egypt (n = 566), Philippines (n = 2076), Pakistan (n = 506), Vietnam (n = 98) and China (n = 503). We conducted an online cross-sectional study that aimed to assess (1) the percentage of vaccinated and unvaccinated students and (2) the reasons associated with willingness/unwillingness to the vaccine. The study included 7255 respondents from 9 countries with a mean age of 21.85 ± 3.66 years. Only 22.11% (n = 1604) of students were vaccinated. However, the majority (69.25%, n = 5025) expressed a willingness to be vaccinated. More willing to vaccinate were students in informal relationships who worked mentally, used psychological/psychiatric services before the pandemic, and studied medicine. There are cultural differences regarding the reasons associated with the unwillingness to vaccinate, but some 'universal' might be distinguished that apply to the whole group.
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- 2022
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32. A Review on Annona muricata and Its Anticancer Activity.
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Ilango S, Sahoo DK, Paital B, Kathirvel K, Gabriel JI, Subramaniam K, Jayachandran P, Dash RK, Hati AK, Behera TR, Mishra P, and Nirmaladevi R
- Abstract
The ongoing rise in the number of cancer cases raises concerns regarding the efficacy of the various treatment methods that are currently available. Consequently, patients are looking for alternatives to traditional cancer treatments such as surgery, chemotherapy, and radiotherapy as a replacement. Medicinal plants are universally acknowledged as the cornerstone of preventative medicine and therapeutic practices. Annona muricata is a member of the family Annonaceae and is familiar for its medicinal properties. A. muricata has been identified to have promising compounds that could potentially be utilized for the treatment of cancer. The most prevalent phytochemical components identified and isolated from this plant are alkaloids, phenols, and acetogenins. This review focuses on the role of A. muricata extract against various types of cancer, modulation of cellular proliferation and necrosis, and bioactive metabolites responsible for various pharmacological activities along with their ethnomedicinal uses. Additionally, this review highlights the molecular mechanism of the role of A. muricata extract in downregulating anti - apoptotic and several genes involved in the pro-cancer metabolic pathways and decreasing the expression of proteins involved in cell invasion and metastasis while upregulating proapoptotic genes and genes involved in the destruction of cancer cells. Therefore, the active phytochemicals identified in A. muricata have the potential to be employed as a promising anti-cancer agent.
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- 2022
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33. Contrasting Association Between COVID-19 Vaccine Hesitancy and Mental Health Status in India and Saudi Arabia-A Preliminary Evidence Collected During the Second Wave of COVID-19 Pandemic.
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Jayakumar S, Ilango S, Kumar K S, Alassaf A, Aljabr A, Paramasivam A, Mickeymaray S, Hawsah YM, and Aldawish AS
- Abstract
Background: Vaccine hesitancy is a global public health threat. Understanding the role of psychological factors in vaccine hesitancy is often neglected and relatively less explored., Aim and Objectives: To analyze the relationship between mental health and COVID-19 vaccine hesitancy before and after the advent of COVID-19 vaccines (AC19V) in the general population of India and Saudi Arabia (KSA) which vary in severity of the pandemic and vaccine mandates., Materials and Methods: A total of 677 adult participants from India and KSA participated in this cross-sectional online web-based survey. Sociodemographic details and current COVID-19 status pertaining to infection and vaccination were collected. Depression, anxiety, post-traumatic stress disorder (PTSD) symptoms, and perceptive need for mental health support (MHS) were assessed before and after AC19V. A newly constructed and validated COVID19 vaccine hesitancy scale-12 (COVID19-VHS12) scale was used to evaluate the COVID-19 vaccine hesitancy., Results: Prevalence and levels of depression and anxiety symptoms decreased significantly in Saudis but not in Indians after AC19V. PTSD symptoms showed a significant reduction in both India and KSA. Anxiety symptoms were higher in KSA than India before AC19V while PTSD was higher in India before and after AC19V. Except for the place of residence and employment status, the subgroups of sociodemographic variables which were at higher risk of negative mental health before AC19V showed improvement in their mental health after AC19V. The prevalence of COVID-19 vaccine hesitancy in India and KSA was 50.8% (95% CI 45.73-55.89%) and 55.7% (95% CI 50.16-61.31%), respectively. A bidirectional association between vaccine hesitancy and mental health was observed in KSA but not in India. Higher vaccine hesitancy favored higher levels of depression, anxiety, and perceptive need for MHS and vice versa in KSA. None of the mental health parameters predicted vaccine hesitancy in India, while higher vaccine hesitancy increased the risk of anxiety., Conclusion: Vaccine hesitancy has a negative impact on mental health and vice versa over and above the impact of sociodemographic factors and COVID-19 vaccination and infection status which shows variations between India and KSA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jayakumar, Ilango, Kumar, Alassaf, Aljabr, Paramasivam, Mickeymaray, Hawsah and Aldawish.)
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- 2022
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34. Comparative Evaluation of Smear Layer Removal in Apical Third Using Four Different Irrigants With Ultrasonic Agitation: An In Vitro Scanning Electron Microscopy (SEM) Analysis.
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Murugesan K, Vishwanath S, Kadandale S, Thanikachalam Y, Parthasarathy R, and Ilango S
- Abstract
Aim This study aims to compare and evaluate the efficacy of four different irrigating solutions like sodium hypochlorite, ethylenediaminetetraacetic (EDTA), Oxum, and ozonated water with ultrasonic agitation in removing the smear layer in the apical third of root canals using Scanning Electron Microscopy (SEM). Materials and methods For the study, 50 freshly extracted human mandibular premolars with single well-developed roots without any curvatures were taken. The teeth taken were decoronated to obtain a uniform working length of 15 mm, and the samples were instrumented using a ProTaper Gold rotary file system (Dentsply Maillefer, Ballaigues, Switzerland) up to F2 size, along with irrigation of 1 ml of 3% sodium hypochlorite (NaOCl) in between instrumentation. The samples were randomly divided into five groups with 10 samples each, according to the final irrigant used. Group I-EDTA 17%, Group II-NaOCl 5%, Group III-Oxum, Group IV-ozonated water, and Group V-normal saline. In all groups, ultrasonic agitation of the irrigating solution was performed using a size 20 file, held passively inside the root canal. Then the samples were flushed with distilled water, dried with paper points, split into two halves, and subjected to SEM analysis. SEM images of the apical third region of root samples were taken at 5000X resolution and scored on a scale of 1 to 4. Results Statistical analysis was done using one-way ANOVA followed by Tukey's post hoc test using software version SPSS software version 17.0 (SPSS Inc., Chicago). The results showed that the 17% EDTA group showed the least smear layer scores when compared to other groups with statistical significance. This was followed by the Oxum group and 5% NaOCl group, whereas the ozone water group and saline control group showed the highest smear layer scores. Conclusion The present study reveals that the EDTA is the superior irrigant in the elimination of smear layer in root canal treatment. Newer irrigants, such as Oxum, can be used as an alternative to EDTA for smear layer removal while remaining biocompatible with dentin. Whereas ozone can be combined with other irrigants for synergistic action of enhanced antimicrobial property and smear layer elimination in the future., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Murugesan et al.)
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- 2022
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35. Extreme heat, preterm birth, and stillbirth: A global analysis across 14 lower-middle income countries.
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McElroy S, Ilango S, Dimitrova A, Gershunov A, and Benmarhnia T
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- Developing Countries, Female, Humans, Income, Infant, Newborn, Pregnancy, Stillbirth epidemiology, Extreme Heat adverse effects, Premature Birth epidemiology
- Abstract
Stillbirths and complications from preterm birth are two of the leading causes of neonatal deaths across the globe. Lower- to middle-income countries (LMICs) are experiencing some of the highest rates of these adverse birth outcomes. Research has suggested that environmental determinants, such as extreme heat, can increase the risk of preterm birth and stillbirth. Under climate change, extreme heat events have become more severe and frequent and are occurring in differential seasonal patterns. Little is known about how extreme heat affects the risk of preterm birth and stillbirth in LMICs. Thus, it is imperative to examine how exposure to extreme heat affects adverse birth outcomes in regions with some of the highest rates of preterm and stillbirths. Most of the evidence linking extreme heat and adverse birth outcomes has been generated from high-income countries (HICs) notably because measuring temperature in LMICs has proven challenging due to the scarcity of ground monitors. The paucity of health data has been an additional obstacle to study this relationship in LMICs. In this study, globally gridded meteorological data was linked with spatially and temporally resolved Demographic and Health Surveys (DHS) data on adverse birth outcomes. A global analysis of 14 LMICs was conducted per a pooled time-stratified case-crossover design with distributed-lag nonlinear models to ascertain the relationship between acute exposure to extreme heat and PTB and stillbirths. We notably found that experiencing higher maximum temperatures and smaller diurnal temperature range during the last week before birth increased the risk of preterm birth and stillbirth. This study is the first global assessment of extreme heat events and adverse birth outcomes and builds the evidence base for LMICs., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2022
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36. Approaches for network based drug discovery.
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Jayachandran P, Ilango S, Paital B, Bhanja S, and Nirmaladevi R
- Subjects
- Biomedical Research, Computational Biology, Humans, Drug Discovery
- Abstract
Molecular network-based studies have gained tremendous importance in biomedical research. Several such advanced technologies in molecular biology have evolved in the past decade and have contributed to building up enormous molecular data. These molecular networks gained much significance among researchers triggering widespread use of experimental and computational tools. This interest led researchers to compile data of biomolecules systematically and to develop various computational tools for analyzing data. In the present scenario, an enormous amount of molecular network databases are available which can be accessed freely by the public. This is the central focus of this article., (© 2021 The Author(s). Published by BRI.)
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- 2021
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37. Mixed phytochemicals mediated synthesis of copper nanoparticles for anticancer and larvicidal applications.
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Rajagopal G, Nivetha A, Sundar M, Panneerselvam T, Murugesan S, Parasuraman P, Kumar S, Ilango S, and Kunjiappan S
- Abstract
The synthesis of copper nanoparticles (CuNPs) using Wrightia tinctoria ( Wt ) R.Br extract is defined in this article as being convenient, environmentally friendly, and non-toxic. UV-visible spectrophotometry, FT-IR, XRD, particle size analyser, SEM-EDAX and TEM methods were used to describe the physicochemical properties of Wt extract mediated synthesized CuNPs ( Wt -CuNPs). The Wt- CuNPs synthesized was found to be monodispersed and spherical, with an average size of 15 nm. Gas chromatography and mass spectrometry (GC-MS) research revealed that the Wt R.Br plant extract contains various phytochemical compounds. The properties of Wt -CuNPs were verified by the findings of characterization tests. Via in silico molecular docking experiments with established targets, the underlying mechanisms of cytotoxicity against breast cancer and larvicidal behaviour against Aedes aegypti of Wt -CuNPs were investigated. Interestingly, in vitro cytotoxicity studies showed 50% cell death (IC
50 ) of Wt- CuNPs treated MCF-7 cells and Vero Cells (Kidney epithelial cells) were displayed at 119.23 μg.mL-1 and 898.75 μg.mL-1 , respectively. Also, Wt- CuNPs showed least LC50 and LC90 values for larvicidal activity against A. aegypti were of 32.10 μg.mL-1 and 21.70 μg.mL-1 , respectively. Furthermore, Wt -CuNPs is found to be less toxic and biocompatible in haemolytic assays. The findings clearly showed that biosynthesized Wt -CuNPs have been used as a possible anticancer and larvicidal agent, as well as being environmentally friendly., Competing Interests: The authors declare no conflict of interest., (© 2021 Published by Elsevier Ltd.)- Published
- 2021
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38. Ambient Fine Particulate Matter and Preterm Birth in California: Identification of Critical Exposure Windows.
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Sheridan P, Ilango S, Bruckner TA, Wang Q, Basu R, and Benmarhnia T
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- Adolescent, Adult, Black or African American, California, Cohort Studies, Female, Humans, Models, Theoretical, Pregnancy, Pregnancy Outcome, Pregnancy Trimesters, Premature Birth ethnology, Proportional Hazards Models, Young Adult, Air Pollutants adverse effects, Maternal Exposure adverse effects, Particulate Matter adverse effects, Premature Birth etiology
- Abstract
Exposure to ambient fine particulate matter (particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5)) during pregnancy is associated with preterm birth (PTB), a leading cause of infant morbidity and mortality. Results from studies attempting to identify etiologically relevant exposure periods of vulnerability have been inconsistent, possibly because of failure to consider the time-to-event nature of the outcome and lagged exposure effects of PM2.5. In this study, we aimed to identify critical exposure windows for weekly PM2.5 exposure and PTB in California using California birth cohort data from 2005-2010. Associations were assessed using distributed-lag Cox proportional hazards models. We assessed effect-measure modification by race/ethnicity by calculating the weekly relative excess risk due to interaction. For a 10-μg/m3 increase in PM2.5 exposure over the entire period of gestation, PTB risk increased by 11% (hazard ratio = 1.11, 95% confidence interval: 1.09, 1.14). Gestational weeks 17-24 and 36 were associated with increased vulnerability to PM2.5 exposure. We find that non-Hispanic black mothers may be more susceptible to effects of PM2.5 exposure than non-Hispanic white mothers, particularly at the end of pregnancy. These findings extend our knowledge about the existence of specific exposure periods during pregnancy that have the greatest impact on preterm birth., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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39. Effect of Fluoxetine on the Hippocampus of Wistar Albino Rats in Cold Restraint Stress Model.
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Jayakumar S, Raghunath G, Ilango S, Vijayakumar J, and Vijayaraghavan R
- Abstract
Introduction: Stress has been known to be a potential modulator of learning and memory. Long term stress can lead to depression. Fluoxetine is a selective serotonin reuptake inhibitor group of drug used in the treatment of depression., Aim: The present study was conducted to evaluate the potential of Fluoxetine on cold restraint induced stress in the hippocampus of Wistar rats., Materials and Methods: A total of 18 male wistar albino rats were divided randomly into three groups (n=6). Group 1 was the control group which were kept in normal laboratory conditions. Group 2 was the negative control group which were given cold restraint stress for period of four weeks. Group 3 was the experimental group, where the animals were pretreated with fluoxetine 10 mg/kg for a period of one week followed by cold restraint stress for 30 minutes and cotreated with fluoxetine 10 mg/kg for a period of four weeks. The whole study was done for a period of five weeks followed by behavioural studies and subsequently sacrificed with removal of brain for various histological, Immunohistochemical (IHC), neurochemical and antioxidant analysis. The values were expressed as Mean±SEM. One-way analysis of variance followed by Tukey's multiple comparisons test was used for the comparison of means. A probability of 0.05 and less was taken as statistically significant using Prism Graphpad software version 6.01., Results: The results show there was significant improvement in the Morris water maze test after treatment with fluoxetine in Group 2. Similar results were also noted in the levels of neurotransmitters and antioxidant levels in brain and also in the number of cells counted in IHC and histological studies by H&E when Group 3 was compared with Group 2. The treatment reversed the damage in Group 2 which was comparable with the control group., Conclusion: The results revealed that administration of fluoxetine 10 mg/kg given orally has a potential antistressor effect by improving the neurogenic and neuroprotective effect on the cold restraint stress induced hippocampal damage.
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- 2017
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40. Forensic psychiatry in India: Past, present, and future.
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Nambi S, Ilango S, and Prabha L
- Abstract
Forensic psychiatry is a subspecialty of psychiatry, in which scientific and clinical expertise is applied to legal issues in legal contexts embracing civil, criminal, correctional, or legislative matters. Forensic psychiatry is still in an infant stage in India and other developing countries. Law is the sanctioning discipline, and Psychiatry is the therapeutic discipline. Due to various reasons, Forensic Psychiatry is reared as Cinderella in our country; "which is much neglected, ignored, misinterpreted, and misunderstood. Legislation forms an integral component in the implementation of Mental Health Care; there is a dynamic relationship between the concept of mental illness, treatment of the mentally ill, and the law. Mental Health legislation is essential in protecting the rights and dignity of persons with Mental Disorders and for implementing effectively the mental health services. "Effective mental health legislation can provide a legal frame work to integrate mental health services in the community as to overcome stigma, discrimination, and exclusion of mentally ill persons. Legislations can also create enforceable standards for high quality medical care and improve access to care and protect civil, political, social, and economic rights of the mentally ill individual, including right to access to education, employment, housing, and social security.", Competing Interests: There are no conflicts of interest.
- Published
- 2016
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41. Functional characterization and microencapsulation of probiotic bacteria from koozh.
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Ilango S, Pandey R, and Antony U
- Abstract
Koozh is a traditional fermented millet beverage unique to south India. Analysis of six market samples of koozh for their microbial profile resulted in 69 isolates of presumptive lactic acid bacteria (LAB). They were grouped as Leuconostoc sp., Enterococcus sp., Streptococcus sp. and Lactobacillus sp. based on morphological characteristics and biochemical tests. Eight among them showed probiotic features: resistance to acid (2.5 pH for 6 h), resistance to 0.3 % ox bile, moderate hydrophobicity (40 %), antibacterial activity against 10 pathogens, susceptibility to 50 % of antibiotics tested. Sequencing of 16srDNA showed them to be five strains of Enterococcus hirae and one each of Enterococcus facecalis, Bacillus amyloliquefaciens and Lactobacillus plantarum. The probiotic isolates were encapsulated in skim milk powder by two different drying techniques: freeze drying and spray drying. The encapsulated probiotic isolates survived both in simulated gastric fluid and simulated intestinal fluid with high cell viability (98-99 %). Storage for 16 weeks at room temperature (27 °C), resulted in 2 log reduction, but better survival with only 1 log reduction was observed at 4 °C and was best at -20 °C. Survival of isolates was similar in both spray and freeze dried products.
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- 2016
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42. Inflammatory pseudotumor of liver secondary to migrated fishbone - a rare cause with an unusual presentation.
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Srinivasan UP, Duraisamy AB, Ilango S, Rathinasamy A, and Chandramohan SM
- Abstract
A 35-year-old woman presented with a history of vague epigastric pain which lasted for one day. She had no other gastrointestinal symptoms and had an unremarkable past history and physical examination. An ultrasound scan abdomen showed a 3×3.5 cm mass in the left lobe of liver. A CT scan showed an abnormal hypodense lesion with mild enhancement in the arterial phase, with a central calcification. Complete blood count, liver function test and alpha-fetoprotein were normal. A left lateral segmentectomy was performed after adequate pre-operative assessment. The specimen contained a 3 cm long fishbone. The post-operative period was uneventful. Histopathological examination revealed chronic non-specific inflammation with fibrosis. Inflammatory pseudotumor of liver is a rare benign tumor with uncertain etiopathogenesis. Suggested etiologies include a septic or a viral origin and it can occur after migration of sharp objects, including migrated fishbone. Inflammatory pseudotumor of liver can be a diagnostic challenge and may end up in major resection.
- Published
- 2013
43. 1-Formyl-r-2,c-6-bis-(4-methoxy-phen-yl)-t-3,t-5-dimethyl-piperidin-4-one.
- Author
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Kavitha T, Sakthivel P, Ponnuswamy S, Ilango SS, and Ponnuswamy MN
- Abstract
In the title compound, C(22)H(25)NO(4), the piperidine ring adopts a distorted boat conformation. The methyl groups at the 3 and 5 positions of the piperidine ring are in axial and equatorial orientations, respectively. Both H and O atoms in the aldehyde group are disordered over two positions with occupancies of 0.534 (5) and 0.466 (5). In the crystal, the mol-ecules are linked into a three-dimensional network by C-H⋯O hydrogen bonds.
- Published
- 2009
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44. 3,3-Dimethyl-cis-2,6-di-p-tolyl-piperidin-4-one.
- Author
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Gayathri P, Ilango SS, Ponnuswamy S, Thiruvalluvar A, and Butcher RJ
- Abstract
In the title mol-ecule, C(21)H(25)NO, the piperidine ring adopts a chair conformation. The benzene rings and one of the methyl groups attached to the piperidine ring have equatorial orientations. The dihedral angle between the two benzene rings is 72.53 (9)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds. Weak C-H⋯π inter-actions involving the benzene rings are also present in the crystal structure.
- Published
- 2009
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45. 2,2,4-Trimethyl-5-(4-tolyl-sulfon-yl)-2,3,4,5-tetra-hydro-1H-1,5-benzo-diazepine.
- Author
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Ravichandran K, Sathiyaraj K, Ilango SS, Ponnuswamy S, and Ponnuswamy MN
- Abstract
In the title compound, C(19)H(24)N(2)O(2)S, the benzodiazepine ring adopts a distorted boat conformation. The S atom shows a distorted tetra-hedral geometry, with the O-S-O [119.16 (14)°] and N-S-C [107.48 (10)°] angles deviating significantly from ideal values. The crystal packing is controlled by C-H⋯O, N-H⋯O and C-H⋯π inter-actions.
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- 2009
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46. r-2,c-6-Bis(4-chloro-phen-yl)-c-3,t-3-dimethyl-piperidin-4-one.
- Author
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Ilango SS, Ponnuswamy S, Gayathri P, Thiruvalluvar A, and Butcher RJ
- Abstract
In the title mol-ecule, C(19)H(19)Cl(2)NO, the piperidine ring adopts a chair conformation and the dihedral angle between the two benzene rings is 77.23 (7)°. In the crystal structure, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, and a weak C-H⋯π inter-action is also observed.
- Published
- 2008
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47. Crystal structure of the apo-PerR-Zn protein from Bacillus subtilis.
- Author
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Traoré DA, El Ghazouani A, Ilango S, Dupuy J, Jacquamet L, Ferrer JL, Caux-Thang C, Duarte V, and Latour JM
- Subjects
- Bacillus subtilis genetics, Bacterial Proteins genetics, Bacterial Proteins metabolism, Binding Sites genetics, Crystallization methods, Cysteine chemistry, Cysteine genetics, Cysteine metabolism, Dimerization, Dithionitrobenzoic Acid chemistry, Gene Expression Regulation, Bacterial, Models, Molecular, Protein Binding, Protein Structure, Secondary, Protein Structure, Tertiary, Repressor Proteins genetics, Repressor Proteins metabolism, Transcription Factors genetics, Transcription Factors metabolism, Zinc metabolism, Bacillus subtilis metabolism, Bacterial Proteins chemistry, Crystallography, X-Ray methods, Repressor Proteins chemistry, Transcription Factors chemistry, Zinc chemistry
- Abstract
Bacteria adapt to elevated levels of Reactive Oxygen Species (ROS) by increasing the expression of defence and repair proteins, which is regulated by ROS responsive transcription factors. In Bacillus subtilis the zinc protein PerR, a peroxide sensor that binds DNA in the presence of a regulatory metal Mn2+ or Fe2+, mediates the adaptive response to H2O2. This study presents the first crystal structure of apo-PerR-Zn which shows that all four cysteine residues of the protein are involved in zinc co-ordination. The Zn(Cys)4 site locks the dimerization domain and stabilizes the dimer. Sequence alignment of PerR-like proteins supports that this structural site may constitute a distinctive feature of this class of peroxide stress regulators.
- Published
- 2006
- Full Text
- View/download PDF
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