38 results on '"Santhosh RS"'
Search Results
2. Memory defects in post-dauer Caenorhabditis elegans are a result of altered insulin signalling.
- Author
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Kanakalatha RS and Thekkuveettil A
- Subjects
- Animals, Memory physiology, Receptor, Insulin metabolism, Receptor, Insulin genetics, Caenorhabditis elegans metabolism, Caenorhabditis elegans physiology, Caenorhabditis elegans genetics, Insulin metabolism, Signal Transduction, Caenorhabditis elegans Proteins metabolism, Caenorhabditis elegans Proteins genetics, Larva metabolism, Larva growth & development
- Abstract
In response to unfavourable conditions and environmental duress, Caenorhabditis elegans follows an alternative developmental stage called the dauer larva, which is associated with various metabolic changes. Dauers can survive in harsh conditions for several months. They resume their development on returning to favourable conditions. This study investigates the impact of altered insulin signalling on memory in post-dauer C. elegans . Our major findings reveal significant deficits in both short- and long-term associative memory in post-dauer nematodes. Through behavioural assays, we demonstrate a robust impairment in memory retrieval, indicating a potential link between the post-dauer state and cognitive dysfunction. Strikingly, we identify that the short-term memory deficit observed in post-dauer worms can be ameliorated by the administration of exogenous insulin. The findings underscore the critical role of insulin signalling in modulating memory processes in post-dauer C. elegans , shedding light on the molecular mechanisms governing memory defects in this developmental stage.
- Published
- 2025
3. Boosting the Production of Hydrogen from an Overall Urea Splitting Reaction Using a Tri-Functional Scandium-Cobalt Electrocatalyst.
- Author
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Tamilarasi S, Kumar RS, Kim AR, Kim HJ, and Yoo DJ
- Abstract
The creation of highly efficient and economical electrocatalysts is essential to the massive electrolysis of water to produce clean energy. The ability to use urea reaction of oxidation (UOR) in place of the oxygen/hydrogen evolution process (OER/HER) during water splitting is a significant step toward the production of high-purity hydrogen with less energy usage. Empirical evidence suggests that the UOR process consists of two stages. First, the metal sites undergo an electrochemical pre-oxidation reaction, and then the urea molecules on the high-valence metal sites are chemically oxidized. Here, the use of scandium-doped CoTe supported on carbon nanotubes called Sc@CoTe/CNT is reported and CoTe/CNT as a composite to efficiently promote hydrogen generation from highly durable and active electrocatalysts for the OER/UOR/HER in urea and alkali solutions. Electrochemical impedance spectroscopy indicates that the UOR facilitates charge transfer across the interface. Furthermore, the Sc@CoTe/CNT nanocatalyst has high performance in KOH and KOH-containing urea solutions as demonstrated by the HER, OER, and UOR (215 mV, 1.59, and 1.31 V, respectively, at 10 mA cm
-2 in 1 m KOH) and CoTe/CNT shows 195 mV, 1.61 and 1.3 V, respectively. Consequently, the total urea splitting system achieves 1.29 V, whereas the overall water splitting device obtaines 1.49 V of Sc@CoTe/CNT and CoTe/CNT shows 1.54, 1.48 V, respectively. This work presents a viable method of combining HER with UOR for maximally effective hydrogen production., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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4. Phenotypic Heterogeneity in ORAI-1-Associated Congenital Myopathy.
- Author
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Baskar D, Vengalil S, Polavarapu K, Preethish-Kumar V, Arunachal G, Sukrutha R, Bardhan M, Huddar A, Unnikrishnan G, Kulkarni GB, Chickabasaviah YT, Kumar RS, Nalini A, and Nashi S
- Abstract
Introduction ORAI-1 is a plasma membrane calcium release-activated calcium channel that plays a crucial role in the excitation-contraction of skeletal muscles. Loss-of-function mutations of ORAI-1 cause severe combined immunodeficiency, nonprogressive muscle hypotonia, and anhidrotic ectodermal dysplasia. Autosomal dominant gain-of-function mutation causes Stormorken's syndrome, which includes tubular aggregate myopathy along with bleeding diathesis. Methods This is a description of a genetically confirmed case of ORAI-1-associated myopathy with clinical, histopathological, and imaging characteristics and a detailed literature review. Results We report an 18-year-old woman who presented with 2-and-a-half year history of slowly progressive proximal lower limb weakness and ophthalmoparesis. Her serum creatine kinase levels were normal. Magnetic resonance imaging of the muscle showed predominant fatty infiltration of the glutei and quadriceps femoris. Histopathological analysis of muscle biopsy was suggestive of congenital fiber-type disproportion (CFTD). Clinical exome sequencing showed novel homozygous nonsense pathogenic variant NC_000012.12 (NM_032790.3): c.205G > T (p.Glu69Ter) in ORAI-1 gene. Conclusion This report expands the phenotypic spectrum of ORAI-1-related myopathy to include congenital myopathy-CFTD with ophthalmoparesis, a novel manifestation., Competing Interests: Conflict of Interest None declared., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. ( https://creativecommons.org/licenses/by/4.0/ ).)
- Published
- 2024
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5. Strong intramolecular charge-transfer effect strengthening naphthoquinone-based chemosensor: Experimental and theoretical evaluation.
- Author
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Sayfiddinov D, Kumar RS, Kaliannagounder VK, Ravichandiran P, Cho KB, Kim CS, Park CH, Shim KS, Choi HW, Park BH, Han MK, and Yoo DJ
- Abstract
An aminophenol-linked naphthoquinone-based fluorometric and colorimetric chemosensor 2-chloro-3-((3-hydroxyphenyl) amino) naphthalene-1,4-dione (2CAN-Dione) was synthesized for selective detection of Sn
2+ ion in aqueous solution. The amine and conversion of carbonyl into carboxyl groups play a vital role in the sensing mechanism when Sn2+ is added to 2CAN-Dione. Comprehensive characterization of the sensor was carried out using standard spectral and analytical approaches. Because of the intramolecular charge transfer (ICT) effect and the turn-on sensing mode, the strong fluorometric emission towards Sn2+ was observed at about 435 nm. The chemosensor exhibited good selectivity for Sn2+ in the presence of coexisting metal ions. An improved linear connection was established with a low limit of detection (0.167 μM). FT-IR,1 H NMR,13 C NMR, and quantum chemistry methods were performed to verify the binding coordination mechanism. The chemosensing probe 2CAN-Dione was successfully employed in bioimaging investigations, demonstrating that it is a reliable fluorescent marker for Sn2+ in human cancer cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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6. Robotic hernia repair with the novel HUGO robot system - An initial experience from a tertiary centre.
- Author
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Jebakumar SGS, Swain SK, Munikrishnan V, Jayapal L, Kumar RS, Baskaran A, Tasgaonkar S, and Srivatsan S
- Abstract
Background: Hernia repair using robotic platforms has been on the rise in the last decade. The HUGO robotic-assisted surgery (RAS) system, introduced in 2021, is a new addition to the field. In this study, we share our experience with this innovative system for the management of ventral and groin hernias., Patients and Methods: The aim of our study was to evaluate the feasibility and safety of using the HUGO robotic platform for hernia surgeries. We conducted a retrospective analysis of all hernia surgeries performed with the HUGO system over a 1-year study period. The study assessed various aspects, including the technical manoeuvres of the robotic system, duration of surgery, length of hospital stay, post-operative pain levels and 30-day morbidity rates., Results and Conclusions: A total of seven hernia surgeries were performed using the HUGO system, including five ventral hernias and two groin hernias. The average duration of surgery was 128 min, with a docking duration of 22.8 min. Notably, there were no intraoperative or post-operative adverse events reported during these procedures. The HUGO system features an open console that provides a panoramic view of the operating room. In addition, the individual arm carts can be easily manoeuvred around the operating table, facilitating improved access to multiple quadrants during surgery. In our case series, Robotic hernia repair using the HUGO system has demonstrated feasibility, with post-operative outcomes comparable to traditional approaches. This innovative system serves as an additional tool in the armamentarium of hernia surgery and shows potential for improving surgical outcomes. However, further investigation through large-scale prospective studies is necessary to comprehensively evaluate its efficacy and benefits., (Copyright © 2024 Copyright: © 2024 Journal of Minimal Access Surgery.)
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- 2024
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7. Insulin signaling in dopaminergic neurons regulates extended memory formation in Caenorhabditis elegans.
- Author
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Kanakalatha RS and Thekkuveettil A
- Subjects
- Animals, Dopaminergic Neurons, Dopamine, Signal Transduction, Insulin, Caenorhabditis elegans
- Abstract
Insulin alters several brain functions, and perturbations in insulin levels could be a precipitating factor for Parkinson's disease, a disease associated with the degeneration of dopaminergic neurons. It is unclear whether insulin alters the dopamine signaling pathway and modulates learning and memory. In Caenorhabditis elegans, daf-2 insulin receptor mutants have extended memory when trained for olfactory adaptation. In this study, we show that the absence of daf-2 receptors in dopamine neurons results in this unusual learning behavior. Our results show that insulin function in memory is dopamine-dependent. In the absence of the daf-2 receptor, the calcium influx in dopamine neurons shows an altered pattern resulting in memory recall for an extended period. These results indicate that learning and memory involve insulin-dopamine crosstalk. Imbalances in this pathway result in changes in memory recall., (© 2023 Wiley Periodicals LLC.)
- Published
- 2024
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8. Trimetallic Oxide Electrocatalyst for Enhanced Redox Activity in Zinc-Air Batteries Evaluated by In Situ Analysis.
- Author
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Kumar RS, Mannu P, Prabhakaran S, Nga TTT, Kim Y, Kim DH, Chen JL, Dong CL, and Yoo DJ
- Abstract
Researchers are investigating innovative composite materials for renewable energy and energy storage systems. The major goals of this studies are i) to develop a low-cost and stable trimetallic oxide catalyst and ii) to change the electrical environment of the active sites through site-selective Mo substitution. The effect of Mo on NiCoMoO
4 is elucidated using both in situ X-ray absorption spectroscopy and X-ray diffraction analysis. Also, density functional theory strategies show that NiCoMoO4 has extraordinary catalytic redox activity because of the high adsorption energy of the Mo atom on the active crystal plane. Further, it is demonstrated that hierarchical nanoflower structures of NiCoMoO4 on reduced graphene oxide can be employed as a powerful bifunctional electrocatalyst for oxygen reduction/evolution reactions in alkaline solutions, providing a small overpotential difference of 0.75 V. Also, Zn-air batteries based on the developed bifunctional electrocatalyst exhibit outstanding cycling stability and a high-power density of 125.1 mW cm-2 . This work encourages the use of Zn-air batteries in practical applications and provides an interesting concept for designing a bifunctional electrocatalyst., (© 2023 Republic of Korea. Advanced Science published by Wiley-VCH GmbH.)- Published
- 2023
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9. Developing Outstanding Bifunctional Electrocatalysts for Rechargeable Zn-Air Batteries Using High-Purity Spinel-Type ZnCo 2 Se 4 Nanoparticles.
- Author
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Kumar RS, Prabhakaran S, Ramakrishnan S, Karthikeyan SC, Kim AR, Kim DH, and Yoo DJ
- Abstract
Zinc-air batteries are gaining popularity as viable energy sources for green energy storage technologies. The cost and performance of Zn-air batteries are mostly determined by the air electrodes in combination with an oxygen electrocatalyst. This research aims at the particular innovations and challenges relating to air electrodes and related materials. Here, a nanocomposite of ZnCo
2 Se4 @rGO that exhibits excellent electrocatalytic activity for the oxygen reduction reaction, ORR (E1/2 = 0.802 V), and oxygen evolution reaction, OER (η10 = 298 mV@10 mA cm-2 ) is synthesized. In addition, a rechargeable zinc-air battery with ZnCo2 Se4 @rGO as the cathode showed a high open circuit voltage (OCV) of 1.38 V, a peak power density of 210.4 mW cm-2 , and outstanding long-term cycling stability. The electronic structure and oxygen reduction/evolution reaction mechanism of the catalysts ZnCo2 Se4 and Co3 Se4 are further investigated using density functional theory calculations. Finally, a perspective for designing, preparing, and assembling air electrodes is suggested for the future developments of high-performance Zn-air batteries., (© 2023 Wiley-VCH GmbH.)- Published
- 2023
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10. Quasihexagonal Platinum Nanodendrites Decorated over CoS 2 -N-Doped Reduced Graphene Oxide for Electro-Oxidation of C1-, C2-, and C3-Type Alcohols.
- Author
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Logeshwaran N, Panneerselvam IR, Ramakrishnan S, Kumar RS, Kim AR, Wang Y, and Yoo DJ
- Abstract
The development of efficient and highly durable materials for renewable energy conversion devices is crucial to the future of clean energy demand. Herein, cage-like quasihexagonal structured platinum nanodendrites decorated over the transition metal chalcogenide core (CoS
2 )-N-doped graphene oxide (PtNDs@CoS2 -NrGO) through optimized shape engineering and structural control technology are fabricated. The prepared electrocatalyst of PtNDs@CoS2 -NrGO is effectively used as anodic catalyst for alcohol oxidation in direct liquid alcohol fuel cells. Notably, the prepared PtNDs@CoS2 -NrGO exhibits superior electrocatalytic performance toward alcohol oxidation with higher oxidation peak current densities of 491.31, 440.25, and 438.12 mA mgpt -1 for (methanol) C1, (ethylene glycol) C2, and (glycerol) C3 fuel electrolytes, respectively, as compared to state-of-the-art Pt-C in acidic medium. The electro-oxidation durability of PtNDs@CoS2 -NrGO is investigated through cyclic voltammetry and chronoamperometry tests, which demonstrate excellent stability of the electrocatalyst toward various alcohols. Furthermore, the surface and adsorption energies of PtNDs and CoS2 are calculated using density functional theory along with the detailed bonding analysis. Overall, the obtained results emphasize the advances in effective precious material utilization and fabricating techniques of active electrocatalysts for direct alcohol oxidation fuel cell applications., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)- Published
- 2022
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11. Epinephrine Plus Vasopressin vs Epinephrine Plus Placebo in Pediatric Intensive Care Unit Cardiopulmonary Resuscitation: A Randomized Double Blind Controlled Clinical Trial.
- Author
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Sheriff A, Rameshkumar R, Chidambaram M, Maulik K, Kumar RS, Jamal A, Bhowmick R, Biswal N, and Mahadevan S
- Subjects
- Aftercare, Child, Epinephrine, Humans, Intensive Care Units, Pediatric, Patient Discharge, Vasopressins, Cardiopulmonary Resuscitation, Heart Arrest
- Abstract
Objective: To compare the efficacy of epinephrine plus vasopressin vs epinephrine plus placebo in the pediatric intensive care unit (PICU) cardiopulmonary resuscitation (CPR)., Design: Randomized, double-blind controlled clinical trial., Setting: PICU in a tertiary care institute from February, 2019 to May, 2020., Participants: Children aged one month to 13 years who required CPR during PICU stay. Patients in whom vascular access was not available or return of spontaneous circulation (ROSC) was achieved by defibrillation without epinephrine were excluded., Intervention: Patients were randomized to receive vasopressin 0.1 mL per kg (=0.8 unit per kg) or placebo (0.1 mL per kg normal saline) in addition to epinephrine (1:10000) 0.1 mL per kg. The drugs were given as bolus doses every three minutes until the ROSC or up to a maximum of five doses, whichever was earlier., Outcome Measure: The primary outcome was the proportion of patients who achieved ROSC. The secondary outcomes were survival rate and functional status (at 24-hour, PICU, hospital, and 90-day post-discharge), need for organ supports, length of stay (PICU and hospital), and adverse effect(s) of the study drugs., Results: 90 patients (epinephrine plus vasopressin group, n=45 and epinephrine plus placebo group, n=45) were analyzed on intention-to-treat basis. There was no significant difference in the primary outcome between epinephrine plus vasopressin (n=25, 55.5%) and epinephrine plus placebo groups (n=24, 53.3%) (Relative risk 1.04, 95% CI 0.71 to 1.52). There was no significant difference in survival rate at 24-hour (n=7, 15.6% vs. n=8, 17.8%), at PICU, hospital, and 90-day post-discharge (n=1, 2.2% vs n=1, 2.2%). There was no difference in other secondary outcomes. No trial drug-related serious adverse events were observed., Conclusions: A combination of epinephrine plus vasopressin did not improve the rate of return of spontaneous circulation in the pediatric intensive care unit cardiopulmonary resuscitation as compared with epinephrine plus placebo.
- Published
- 2021
12. Tuberculous Meningitis Fitting the Shoes of Incomplete Kawasaki Disease.
- Author
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Lingesan K, Maya M, Ramamoorthy JG, Karunakar P, Gunasekaran D, Thangavel NP, Kumar RS, and Kumar VR
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- Humans, Mucocutaneous Lymph Node Syndrome, Tuberculosis, Meningeal diagnosis
- Published
- 2020
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13. Higher levels of lysosomal associated membrane protein-2 (LAMP-2) in plasma exosomes from Alzheimer's disease: An exploratory study from South India.
- Author
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Krishna G, Kn A, Kumar RS, Sagar BC, Philip M, Dahale AB, Issac TG, Mukku SSR, Sivakumar PT, and Subramanian S
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- Aged, Aged, 80 and over, Exosomes, Female, Humans, India, Male, Middle Aged, Alzheimer Disease blood, Lysosomal-Associated Membrane Protein 2 blood
- Abstract
Competing Interests: Declaration of Competing Interest None.
- Published
- 2020
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14. Proteomic Analysis of the Human Anterior Pituitary Gland.
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Yelamanchi SD, Tyagi A, Mohanty V, Dutta P, Korbonits M, Chavan S, Advani J, Madugundu AK, Dey G, Datta KK, Rajyalakshmi M, Sahasrabuddhe NA, Chaturvedi A, Kumar A, Das AA, Ghosh D, Jogdand GM, Nair HH, Saini K, Panchal M, Sarvaiya MA, Mohanraj SS, Sengupta N, Saxena P, Subramani PA, Kumar P, Akkali R, Reshma SV, Santhosh RS, Rastogi S, Kumar S, Ghosh SK, Irlapati VK, Srinivasan A, Radotra BD, Mathur PP, Wong GW, Satishchandra P, Chatterjee A, Gowda H, Bhansali A, Pandey A, Shankar SK, Mahadevan A, and Prasad TSK
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- Chromatography, Liquid, Humans, Mass Spectrometry, Pituitary Gland, Anterior metabolism, Proteome metabolism, Proteomics methods
- Abstract
The pituitary function is regulated by a complex system involving the hypothalamus and biological networks within the pituitary. Although the hormones secreted from the pituitary have been well studied, comprehensive analyses of the pituitary proteome are limited. Pituitary proteomics is a field of postgenomic research that is crucial to understand human health and pituitary diseases. In this context, we report here a systematic proteomic profiling of human anterior pituitary gland (adenohypophysis) using high-resolution Fourier transform mass spectrometry. A total of 2164 proteins were identified in this study, of which 105 proteins were identified for the first time compared with high-throughput proteomic-based studies from human pituitary glands. In addition, we identified 480 proteins with secretory potential and 187 N-terminally acetylated proteins. These are the first region-specific data that could serve as a vital resource for further investigations on the physiological role of the human anterior pituitary glands and the proteins secreted by them. We anticipate that the identification of previously unknown proteins in the present study will accelerate biomedical research to decipher their role in functioning of the human anterior pituitary gland and associated human diseases.
- Published
- 2018
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15. Integrated pathology and radiology learning for a musculoskeletal system module: an example of interdisciplinary integrated form.
- Author
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Karri RS, Kale AU, and Maria N
- Abstract
Competing Interests: Disclosure The authors report no conflicts of interest in this communication.
- Published
- 2018
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16. Synthesis of Bioactive 3,4-Dihydro-2 H-naphtho[2,3- b][1,4]oxazine-5,10-dione and 2,3,4,5-Tetrahydro-1 H-naphtho[2,3- b]azepine-6,11-dione Derivatives via the Copper-Catalyzed Intramolecular Coupling Reaction.
- Author
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You H, Vegi SR, Lagishetti C, Chen S, Reddy RS, Yang X, Guo J, Wang C, and He Y
- Subjects
- A549 Cells, Azepines chemistry, Azepines pharmacology, Catalysis, Humans, Molecular Structure, Oxazines chemistry, Oxazines pharmacology, Azepines chemical synthesis, Copper chemistry, Oxazines chemical synthesis
- Abstract
A convenient synthesis of 3,4-dihydro-2 H-naphtho[2,3- b][1,4]oxazine-5,10-diones and 2,3,4,5-tetrahydro-1 H-naphtho[2,3- b]azepine-6,11-diones via the copper-catalyzed intramolecular C-O/C-C coupling reaction is described. This method showed a good tolerance for functional groups and was applied to the synthesis of natural product core structures. Some coupling products exhibited moderate activities against lung cancer A549 cells.
- Published
- 2018
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17. Endoribonuclease type II toxin-antitoxin systems: functional or selfish?
- Author
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Ramisetty BCM and Santhosh RS
- Subjects
- Antitoxins genetics, Bacteria genetics, Bacterial Toxins genetics, Endoribonucleases genetics, Antitoxins metabolism, Bacteria metabolism, Bacterial Toxins metabolism, Endoribonucleases metabolism, Toxin-Antitoxin Systems
- Abstract
Most bacterial genomes have multiple type II toxin-antitoxin systems (TAs) that encode two proteins which are referred to as a toxin and an antitoxin. Toxins inhibit a cellular process, while the interaction of the antitoxin with the toxin attenuates the toxin's activity. Endoribonuclease-encoding TAs cleave RNA in a sequence-dependent fashion, resulting in translational inhibition. To account for their prevalence and retention by bacterial genomes, TAs are credited with clinically significant phenomena, such as bacterial programmed cell death, persistence, biofilms and anti-addiction to plasmids. However, the programmed cell death and persistence hypotheses have been challenged because of conceptual, methodological and/or strain issues. In an alternative view, chromosomal TAs seem to be retained by virtue of addiction at two levels: via a poison-antidote combination (TA proteins) and via transcriptional reprogramming of the downstream core gene (due to integration). Any perturbation in the chromosomal TA operons could cause fitness loss due to polar effects on the downstream genes and hence be detrimental under natural conditions. The endoribonucleases encoding chromosomal TAs are most likely selfish DNA as they are retained by bacterial genomes, even though TAs do not confer a direct advantage via the TA proteins. TAs are likely used by various replicons as 'genetic arms' that allow the maintenance of themselves and associated genetic elements. TAs seem to be the 'selfish arms' that make the best use of the 'arms race' between bacterial genomes and plasmids.
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- 2017
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18. Corrigendum: What Is the Link between Stringent Response, Endoribonuclease Encoding Type II Toxin-Antitoxin Systems and Persistence?
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Ramisetty BC, Ghosh D, Roy Chowdhury M, and Santhosh RS
- Abstract
[This corrects the article on p. 1882 in vol. 7, PMID: 27933045.].
- Published
- 2017
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19. Selective Aza Diels-Alder and Domino [4+2]/[2+2] Cycloaddition Reactions of Arynes with N-Sulfonyl Ketimines.
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Kiran IN, Reddy RS, Lagishetti C, Xu H, Wang Z, and He Y
- Abstract
Transition-metal-free inverse electron-demand aza Diels-Alder and domino [4+2]/[2+2] cycloaddition reaction of arynes and N-sulfonyl ketimines has been demonstrated. This novel, mild, and efficient protocol allows rapid access to isothiazole dioxide-fused dihydroquinoline or dihydrocyclobutaquinoline derivatives selectively by simply varying the equivalents of aryne precursors. The application of this method has been amply illustrated in the synthesis of 2,4-diarylquinolines.
- Published
- 2017
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20. What Is the Link between Stringent Response, Endoribonuclease Encoding Type II Toxin-Antitoxin Systems and Persistence?
- Author
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Ramisetty BC, Ghosh D, Roy Chowdhury M, and Santhosh RS
- Abstract
Persistence is a transient and non-inheritable tolerance to antibiotics by a small fraction of a bacterial population. One of the proposed determinants of bacterial persistence is toxin-antitoxin systems (TASs) which are also implicated in a wide range of stress-related phenomena. Maisonneuve E, Castro-Camargo M, Gerdes K. 2013. Cell 154:1140-1150 reported an interesting link between ppGpp mediated stringent response, TAS, and persistence. It is proposed that accumulation of ppGpp enhances the accumulation of inorganic polyphosphate which modulates Lon protease to degrade antitoxins. The decrease in the concentration of antitoxins supposedly activated the toxin to increase in the number of persisters during antibiotic treatment. In this study, we show that inorganic polyphosphate is not required for transcriptional activation of yefM/yoeB TAS, which is an indirect indication of Lon-dependent degradation of YefM antitoxin. The Δ10 strain, an Escherichia coli MG1655 derivative in which the 10 TAS are deleted, is more sensitive to ciprofloxacin compared to wild type MG1655. Furthermore, we show that the Δ10 strain has relatively lower fitness compared to the wild type and hence, we argue that the persistence related implications based on Δ10 strain are void. We conclude that the transcriptional regulation and endoribonuclease activity of YefM/YoeB TAS is independent of ppGpp and inorganic polyphosphate. Therefore, we urge for thorough inspection and debate on the link between chromosomal endoribonuclease TAS and persistence.
- Published
- 2016
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21. Synthesis of Dihydrophenanthridines and Oxoimidazolidines from Anilines and Ethylglyoxylate via Aza Diels-Alder Reaction of Arynes and KF-Induced Annulation.
- Author
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Reddy RS, Lagishetti C, Chen S, Kiran IN, and He Y
- Abstract
The transition-metal-free multicomponent coupling of arynes, anilines, and ethylglyoxylate, proceeding via an inverse electron-demand aza Diels-Alder cycloaddition and N-arylation, has been demonstrated. This protocol allows rapid access to N-aryl dihydrophenanthridine derivatives in moderate to high yields at room temperature from readily available starting materials. In addition, an unprecedented fluoride induced annulation of ethyl(arylimino)acetates led to the formation of highly functionalized oxoimidazolidine derivatives in good yields under mild conditions.
- Published
- 2016
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22. Streptomycin affinity depends on 13 amino acids forming a loop in homology modelled ribosomal S12 protein (rpsL gene) of Lysinibacillus sphaericus DSLS5 associated with marine sponge (Tedania anhelans).
- Author
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Suriyanarayanan B, Lakshmi PP, Santhosh RS, Dhevendaran K, Priya B, and Krishna S
- Subjects
- Amino Acid Sequence, Animals, Escherichia coli Proteins, Ligands, Molecular Docking Simulation, Molecular Dynamics Simulation, Protein Binding, Ribosomal Protein S9, Ribosomal Proteins metabolism, Streptomycin metabolism, Structure-Activity Relationship, Bacillaceae genetics, Bacillaceae metabolism, Models, Molecular, Molecular Conformation, Porifera microbiology, Ribosomal Proteins chemistry, Streptomycin chemistry
- Abstract
Streptomycin, an antibiotic used against microbial infections, inhibits the protein synthesis by binding to ribosomal protein S12, encoded by rpsL12 gene, and associated mutations cause streptomycin resistance. A streptomycin resistant, Lysinibacillus sphaericus DSLS5 (MIC >300 µg/mL for streptomycin), was isolated from a marine sponge (Tedania anhelans). The characterisation of rpsL12 gene showed a region having similarity to long terminal repeat sequences of murine lukemia virus which added 13 amino acids for loop formation in RpsL12; in addition, a K56R mutation which corresponds to K43R mutation present in streptomycin-resistant Escherichia coli is also present. The RpsL12 protein was modelled and compared with that of Lysinibacillus boronitolerans, Escherichia coli and Mycobacterium tuberculosis. The modelled proteins docked with streptomycin indicate compound had less affinity. The effect of loop on streptomycin resistance was analysed by constructing three different models of RpsL12 by, (i) removing both loop and mutation, (ii) removing the loop alone while retaining the mutation and (iii) without mutation having loop. The results showed that the presence of loop causes streptomycin resistance (decreases the affinity), and it further enhanced in the presence of mutation at 56th codon. Further study will help in understanding the evolution of streptomycin resistance in organisms.
- Published
- 2016
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23. Synthesis of Carbazolequinones by Formal [3 + 2] Cycloaddition of Arynes and 2-Aminoquinones.
- Author
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Guo J, Kiran IN, Reddy RS, Gao J, Tang M, Liu Y, and He Y
- Abstract
A formal cycloaddition reaction for the synthesis of biologically and pharmaceutically important carbazolequinones via the annulation of aminoquinones with arynes has been developed. This practical and metal-free cascade reaction proceeds through successive C-C/C-N bond formations. Moreover, this novel method has been utilized for the concise synthesis of bioactive murrayaquinone A and koeniginequinone B and their analogues.
- Published
- 2016
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24. Coexistence of central nucleus, cores, and rods: Diagnostic relevance.
- Author
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Dhinakaran S, Kumar RS, Thakkar R, and Narayanappa G
- Abstract
Background: Congenital myopathies (CMs) though considered distinct disorders, simultaneous occurrence of central nucleus, nemaline rods, and cores in the same biopsy are scarcely reported., Objective: A retrospective reassessment of cases diagnosed as CMs to look for multiple pathologies missed, if any, during the initial diagnosis., Materials and Methods: Enzyme histochemical, and immunohistochemical-stained slides from 125 cases diagnosed as congenital myopathy were reassessed., Results: The study revealed 15 cases (12%) of congenital myopathy with more than one morphological feature. Central nucleus with cores (n = 11), central nucleus, nemaline rods and cores (n = 3), and nemaline rods with cores (n = 1). 4/11 cases were diagnosed as centronuclear myopathy (CNM) in the first instance; in addition, cores were revealed on reassessment., Discussion: The prevalence of CMs of all neuromuscular disorders is approximately 6 in 100,000 live births, with regional variations. Three main defined CMs include centro nuclear myopathy (CNM), nemaline rod myopathy (NRM), and central core disease (CCD). However, they are more diverse with overlapping clinical and histopathological features, thus broadening the spectra within each category of congenital myopathy., Conclusion: Identification of cases with overlap of pathological features has diagnostic relevance.
- Published
- 2016
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25. Horizontal gene transfer of chromosomal Type II toxin-antitoxin systems of Escherichia coli.
- Author
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Ramisetty BC and Santhosh RS
- Subjects
- Computational Biology, Genetic Variation, Bacterial Toxins genetics, Escherichia coli genetics, Gene Transfer, Horizontal
- Abstract
Type II toxin-antitoxin systems (TAs) are small autoregulated bicistronic operons that encode a toxin protein with the potential to inhibit metabolic processes and an antitoxin protein to neutralize the toxin. Most of the bacterial genomes encode multiple TAs. However, the diversity and accumulation of TAs on bacterial genomes and its physiological implications are highly debated. Here we provide evidence that Escherichia coli chromosomal TAs (encoding RNase toxins) are 'acquired' DNA likely originated from heterologous DNA and are the smallest known autoregulated operons with the potential for horizontal propagation. Sequence analyses revealed that integration of TAs into the bacterial genome is unique and contributes to variations in the coding and/or regulatory regions of flanking host genome sequences. Plasmids and genomes encoding identical TAs of natural isolates are mutually exclusive. Chromosomal TAs might play significant roles in the evolution and ecology of bacteria by contributing to host genome variation and by moderation of plasmid maintenance., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2016
- Full Text
- View/download PDF
26. SarA based novel therapeutic candidate against Staphylococcus aureus associated with vascular graft infections.
- Author
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Arya R, Ravikumar R, Santhosh RS, and Princy SA
- Abstract
Staphylococcus aureus is a common pathogen seen in prosthetic vascular graft, leading to high morbidity and mortality. The virulence genes for severity of infections are under the control of global regulators. Staphylococcal accessory regulator A (SarA) a known master controller of biofilm formation is an attractive target for the drug development. A structure based screening of lead compounds was employed for the identification of novel small molecule inhibitors targeted to interact to the DNA binding domain of the transcriptional activator, SarA and hinder its response over the control of genes that up-regulate the phenotype, biofilm. The top-hit SarA selective inhibitor, 4-[(2,4-diflurobenzyl)amino] cyclohexanol (SarABI) was further validated in-vitro for its efficacy. The SarABI was found to have MBIC50value of 200 μg/ml and also down-regulated the expression of the RNA effector, (RNAIII), Hemolysin (hld), and fibronectin-binding protein (fnbA). The anti-adherence property of SarABI on S. aureus invasion to the host epithelial cell lines (Hep-2) was examined where no significant attachment of S. aureus was observed. The SarABI inhibits the colonization of MDR S. aureus in animal model experiment significantly cohere to the molecular docking studies and in vitro experiments. So, we propose that the SarABI could be a novel substitute to overcome a higher degree of MDR S. aureus colonization on vascular graft.
- Published
- 2015
- Full Text
- View/download PDF
27. Perceived myths about oral health in India.
- Author
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Mythri H and Kumar RS
- Subjects
- Female, Humans, Male, Attitude to Health, Mythology, Oral Hygiene, Rural Population, Tobacco Use
- Published
- 2015
- Full Text
- View/download PDF
28. mazEF-mediated programmed cell death in bacteria: "what is this?".
- Author
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Ramisetty BC, Natarajan B, and Santhosh RS
- Subjects
- Escherichia coli physiology, Stress, Physiological, Bacterial Physiological Phenomena, Cell Death, DNA-Binding Proteins, Endoribonucleases, Escherichia coli Proteins, Microbial Viability
- Abstract
Toxin-antitoxin (TA) systems consist of a bicistronic operon, encoding a toxin and an antitoxin. They are widely distributed in the prokaryotic kingdom, often in multiple numbers. TAs are implicated in contradicting phenomena of persistence and programmed cell death (PCD) in bacteria. mazEF TA system, one of the widely distributed type II toxin-antitoxin systems, is particularly implicated in PCD of Escherichia coli. Nutrient starvation, antibiotic stress, heat shock, DNA damage and other kinds of stresses are shown to elicit mazEF-mediated-PCD. ppGpp and extracellular death factor play a central role in regulating mazEF-mediated PCD. The activation of mazEF system is achieved through inhibition of transcription or translation of mazEF loci. Upon activation, MazF cleaves RNA in a ribosome-independent fashion and subsequent processes result in cell death. It is hypothesized that PCD aids in perseverance of the population during stress; the surviving minority of the cells can scavenge the nutrients released by the dead cells, a kind of "nutritional-altruism." Issues regarding the strains, reproducibility of experimental results and ecological plausibility necessitate speculation. We review the molecular mechanisms of the activation of mazEF TA system, the consequences leading to cell death and the pros and cons of the altruism hypothesis from an ecological perspective.
- Published
- 2015
- Full Text
- View/download PDF
29. Selective transfection with osmotically active sorbitol modified PEI nanoparticles for enhanced anti-cancer gene therapy.
- Author
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Nguyen KC, Muthiah M, Islam MA, Kalash RS, Cho CS, Park H, Lee IK, Kim HJ, Park IK, and Cho KA
- Subjects
- Animals, Apoptosis, Caveolae metabolism, Cell Line, Tumor, Endocytosis, Gene Expression, Genetic Therapy, Humans, Lipids chemistry, Luciferases genetics, Luciferases metabolism, Macrophages, Peritoneal cytology, Macrophages, Peritoneal metabolism, Mice, Particle Size, Polyethyleneimine chemistry, Primary Cell Culture, Static Electricity, Transgenes, Tumor Suppressor Protein p53 metabolism, Gene Transfer Techniques, Nanoparticles chemistry, Plasmids metabolism, Polyesters chemistry, Polyethyleneimine analogs & derivatives, Tumor Suppressor Protein p53 genetics
- Abstract
Polysorbitol-mediated transporter (PSMT) has been previously shown to achieve high transfection efficiency with minimal cytotoxicity. Polysorbitol backbone possesses osmotic properties and leads to enhanced cellular uptake. The PSMT/pDNA nanoparticles were prepared and the particle size, surface charge of the nanoparticles was determined for the study. PSMT delivers genes into cells by the caveolae mediated endocytic pathway. Caveolae expression is usually altered in transformed cancer cells. Transfection through the caveolae may help PSMT to selectively transfect cancer cells rather than normal cells. Transfection of the luciferase gene by PSMT was tested in various cell types including cancer cell lines, primary cells, and immortalized cells. Luciferase transgene expression mediated by PSMT was remarkably increased in HeLa cells compared to expression using the control carrier Lipofectamine. Moreover, the toxicity of PSMT was comparable to the control carrier (Lipofectamine) in the same cells. Selective transfection of cancer cells using PSMT was further confirmed by co-culture of cancer and normal cells, which showed that transgene expression was pre-dominantly achieved in cancer cells. A functional p53 gene was also delivered into HeLa cells using PSMT and the selective transgene expression of p53 protein in cancer cells was analyzed through western blotting and confocal microscopy. HeLa cells transfected with PSMT/p53 plasmid nanoparticles showed cellular damage and apoptosis, which was confirmed through propidium iodide staining., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
30. Plants: a source for new antimycobacterial drugs.
- Author
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Santhosh RS and Suriyanarayanan B
- Subjects
- Alkaloids chemistry, Alkaloids pharmacology, Anti-Bacterial Agents isolation & purification, Chalcones chemistry, Chalcones pharmacology, Coumarins chemistry, Coumarins pharmacology, Fatty Acids chemistry, Fatty Acids pharmacology, Flavonoids chemistry, Flavonoids pharmacology, Medicine, Traditional, Microbial Sensitivity Tests, Mycobacterium drug effects, Phenols chemistry, Phenols pharmacology, Quinones chemistry, Quinones pharmacology, Terpenes chemistry, Terpenes pharmacology, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Antitubercular Agents pharmacology, Plants chemistry
- Abstract
Tuberculosis, also called TB, is currently a major health hazard due to multidrug-resistant forms of bacilli. Global efforts are underway to eradicate TB using new drugs with new modes of action, higher activity, and fewer side effects in combination with vaccines. For this reason, unexplored new sources and previously explored sources were examined and around 353 antimycobacterial compounds (Nat Prod Rep 2007; 24: 278-297) 7 have been previously reported. To develop drugs from these new sources, additional work is required for preclinical and clinical results. Since ancient times, different plant part extracts have been used as traditional medicines against diseases including tuberculosis. This knowledge may be useful in developing future powerful drugs. Plant natural products are again becoming important in this regard. In this review, we report 127 antimycobacterial compounds and their antimycobacterial activities. Of these, 27 compounds had a minimum inhibitory concentration of < 10 µg/mL. In some cases, the mechanism of activity has been determined. We hope that some of these compounds may eventually develop into effective new drugs against tuberculosis., (Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2014
- Full Text
- View/download PDF
31. CuCN-mediated cascade cyclization of 4-(2-bromophenyl)-2-butenoates: a high-yield synthesis of substituted naphthalene amino esters.
- Author
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Reddy RS, Prasad PK, Ahuja BB, and Sudalai A
- Subjects
- Cyclization, Esters chemistry, Molecular Structure, Naphthalenes chemistry, Copper chemistry, Cyanides chemistry, Esters chemical synthesis, Naphthalenes chemical synthesis, Phenylbutyrates chemistry
- Abstract
A new method of CuCN-mediated one-pot cyclization of 4-(2-bromophenyl)-2-butenoates leading to efficient synthesis of substituted naphthalene amino esters including phenanthrene aromatic structural units is described. Deuterium labeling studies establish that this one-pot cascade cyclization proceeds through isomerization of olefin, intramolecular C-C bond cyclization, and aromatization as the key intermediates, all occurring in a single step.
- Published
- 2013
- Full Text
- View/download PDF
32. CN-assisted oxidative cyclization of cyano cinnamates and styrene derivatives: a facile entry to 3-substituted chiral phthalides.
- Author
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Reddy RS, Kiran IN, and Sudalai A
- Subjects
- Benzofurans chemistry, Cyclization, Molecular Structure, Oxidation-Reduction, Benzofurans chemical synthesis, Cinnamates chemistry, Nitriles chemistry, Styrenes chemistry
- Abstract
The asymmetric dihydroxylation (AD) of o-cyano cinnamates and styrene derivatives leads to efficient construction of chiral phthalide frameworks in high optical purities. This unique reaction is characterized by unusual synergism between CN and osmate groups resulting in rate enhancement of the AD process. The method is amply demonstrated by the synthesis and the structural/stereochemical assignment of the natural products.
- Published
- 2012
- Full Text
- View/download PDF
33. Impaired neutrophil and monocyte chemotaxis in chronic and aggressive periodontitis and effects of periodontal therapy.
- Author
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Kumar RS and Prakash S
- Subjects
- Adult, Aggressive Periodontitis blood, Aggressive Periodontitis therapy, Alveolar Bone Loss classification, Anti-Bacterial Agents therapeutic use, Case-Control Studies, Chronic Periodontitis blood, Chronic Periodontitis therapy, Dental Plaque Index, Dental Scaling methods, Double-Blind Method, Female, Follow-Up Studies, Humans, Male, Middle Aged, Occlusal Adjustment, Oral Hygiene, Periodontal Index, Periodontal Pocket classification, Risk Factors, Root Planing methods, Surgical Flaps, Tetracycline therapeutic use, Aggressive Periodontitis immunology, Chemotaxis, Leukocyte immunology, Chronic Periodontitis immunology, Monocytes immunology, Neutrophils immunology
- Abstract
Background and Objectives: Depressed chemotactic activity of polymorphoneutrophil (PMN) and monocyte (MN) appears to be one of the significant risk factors in the development of periodontal disease. Although bacteria are the primary etiologic factor in periodontal disease, the patient's host response is a determinant of disease susceptibility. Depressed chemotaxis of PMN and MN could lead to periodontal destruction by altering the host response i.e. impairment of the normal host response in neutralizing infection and alterations that result in destruction of the surrounding periodontal tissues., Materials and Methods: Thirty patients (10 healthy subjects, 10 chronic periodontitis, and 10 with aggressive periodontitis) participated in this study. Clinical parameters like plaque index, gingival index, probing pocket depth, and radiographic assessment were done. The peripheral blood PMNs and MNs were isolated from the patient and the chemotactic response was studied. Statistical analysis was performed using post-hoc Newman-Keul range test., Results: PMN and MN chemotaxis was found to be statistically significant (P<0.05) at baseline and three months after periodontal therapy in chronic and aggressive periodontitis group compared to healthy subjects. However on comparison between chronic and aggressive periodontitis group statistical significance was not found (P>0.05).Comparision between chronic periodontitis, aggressive periodontitis with healthy subjects, PMN and MN chemotaxis showed statistical significance (P<0.05) at baseline and three months after periodontal therapy, Whereas statistically there was no difference when chronic periodontitis was compared with aggressive periodontitis., Interpretation and Conclusion: Depressed chemotaxis of PMN and MN results in increased periodontal destruction. In this study, depressed PMN and MN chemotaxis is seen in both aggressive periodontitis group and chronic periodontitis group and the response was altered although to a lesser degree after periodontal therapy in both groups indicating that effect of treatment does exist.
- Published
- 2012
- Full Text
- View/download PDF
34. Comparative proteomics of human male and female tears by two-dimensional electrophoresis.
- Author
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Ananthi S, Santhosh RS, Nila MV, Prajna NV, Lalitha P, and Dharmalingam K
- Subjects
- Electrophoresis, Gel, Two-Dimensional methods, Fatty Alcohols pharmacology, Female, Humans, Isoelectric Focusing, Male, Molecular Sequence Data, Peptide Fragments analysis, Proteomics methods, Sequence Analysis, Protein, Sex Factors, Tandem Mass Spectrometry, Eye Proteins analysis, Proteome analysis, Tears chemistry
- Abstract
The proteomic profile of tear fluid is of fundamental interest in eye research. In this study we optimized the tear sample preparation method for two-dimensional (2D) analysis and determined the protein profile of tear fluid from healthy males and females. To find the most efficient method for tear sample preparation, four widely applied precipitation methods and ultrafiltration were compared. Of these, TCA precipitation & ultrafiltration resulted in efficient sample concentration and desalting. Use of a nonionic wetting agent, Tergitol NP7, in rehydration solution during isoelectric focusing improves protein separation in 2D gel electrophoresis considerably. Using this optimized method, tear protein profile was analyzed from healthy males and females. Of the thirty six tear proteins identified by LC-MS/MS, seven tear proteins were found to be significantly up regulated in the healthy female tear samples when compared to the male tear samples. These results indicate that the tear protein profile differs with respect to the sex. Mostly, the up regulated proteins are involved in the local immune defense; implying that there may be a sex difference in the ability to defend against infection at the anterior segment of the eyes of normal individuals., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
35. Co(III)(salen)-catalyzed HKR of two stereocentered alkoxy- and azido epoxides: a concise enantioselective synthesis of (S,S)-reboxetine and (+)-epi-cytoxazone.
- Author
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Reddy RS, Chouthaiwale PV, Suryavanshi G, Chavan VB, and Sudalai A
- Subjects
- Antidepressive Agents chemistry, Catalysis, Morpholines chemistry, Oxazoles chemistry, Reboxetine, Stereoisomerism, Antidepressive Agents chemical synthesis, Cobalt chemistry, Coordination Complexes chemistry, Epoxy Compounds chemistry, Ethylenediamines chemistry, Morpholines chemical synthesis, Oxazoles chemical synthesis
- Abstract
The HKR of racemic syn- or anti- alkoxy- and azido epoxides catalyzed by Co(salen) complex affords a practical access to a series of enantioenriched syn- or anti- alkoxy- and azido epoxides and the corresponding 1,2-diols. This strategy has been successfully employed in the concise, enantioselective synthesis of bioactive molecules such as (S,S)-reboxetine and (+)-epi-cytoxazone.
- Published
- 2010
- Full Text
- View/download PDF
36. Lennox-Gastaut syndrome: An overview.
- Author
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Ramanathan RS, Ahluwalia T, and Sharma A
- Published
- 2010
- Full Text
- View/download PDF
37. Asymmetric synthesis of tetrahydroquinolin-3-ols via CoCl2-catalyzed reductive cyclization of nitro cyclic sulfites with NaBH4.
- Author
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Jagdale AR, Reddy RS, and Sudalai A
- Subjects
- Benzimidazoles chemistry, Benzimidazoles pharmacology, Catalysis, Cyclization, Molecular Structure, Oligopeptides chemistry, Oligopeptides pharmacology, Quinolinium Compounds chemistry, Quinolinium Compounds pharmacology, Tetrahydroisoquinolines chemistry, Benzimidazoles chemical synthesis, Borohydrides chemistry, Cobalt chemistry, Nitro Compounds chemistry, Oligopeptides chemical synthesis, Quinolinium Compounds chemical synthesis, Sulfites chemistry, Tetrahydroisoquinolines chemical synthesis
- Abstract
A new method for the construction of chiral 3-substituted tetrahydroquinoline derivatives based on asymmetric dihydroxylation and CoCl(2)-catalyzed reductive cyclization of nitro cyclic sulfites with NaBH(4) has been described with high optical purities. This method has been successfully applied in the formal synthesis of PNU 95666E and anachelin H chromophore.
- Published
- 2009
- Full Text
- View/download PDF
38. Cloning of mce1 locus of Mycobacterium leprae in Mycobacterium smegmatis mc2 155 SMR5 and evaluation of expression of mce1 genes in M. smegmatis and M. leprae.
- Author
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Santhosh RS, Pandian SK, Lini N, Shabaana AK, Nagavardhini A, and Dharmalingam K
- Subjects
- Attachment Sites, Microbiological genetics, Base Sequence, Cloning, Molecular, DNA, Bacterial genetics, Gene Expression, Genetic Vectors, Humans, Leprosy, Lepromatous microbiology, Molecular Sequence Data, Mycobacterium leprae pathogenicity, Operon, Plasmids genetics, RNA, Bacterial genetics, RNA, Bacterial metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Reverse Transcriptase Polymerase Chain Reaction, Sequence Homology, Nucleic Acid, Species Specificity, Transformation, Genetic, Bacterial Proteins genetics, Genes, Bacterial, Mycobacterium leprae genetics, Mycobacterium smegmatis genetics
- Abstract
Plasmid pSET152 is a broad host range mobilizable vector which integrates into streptomyces chromosome utilizing att site and int function of slashed circleC31. Transformation of this plasmid into Mycobacterium smegmatis mc2 155 SMR5 gave stable transformants carrying the pSET152 as an integrated copy. Integration occurred at the cross over sequence 5'TTG disrupting the gatA gene (Glu-tRNA(Gln) amidotransferase subunitA), which is non-essential under conditions used. Recombinant pSET152 plasmids carrying mce1 locus of Mycobacterium leprae were used to construct M. smegmatis transformants carrying the mce1 locus in their chromosome. RT-PCR analysis revealed specific transcripts of M. leprae mce in M. smegmatis. The transcribed mRNA carried intergenic regions between genes of mce1 locus indicating that mce1 locus is an operon. Examination of M. leprae specific mRNA from lepromatous leprosy patient's biopsy showed that mce locus is transcribed as an operon in the pathogen also.
- Published
- 2005
- Full Text
- View/download PDF
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