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Shats D, Balasubramanian T, Sidelnikov D, Das U, Onyekaba NA, Forbes HE, Lu N, Williams K, Levin MR, Sundararajan S, Vij S, Gadagkar H, Rege A, Saeedi O, Chen V, Alexander JL. Association of Speckle-Based Blood Flow Measurements and Fluorescein Angiography in Infants with Retinopathy of Prematurity. Ophthalmol Sci 2024; 4:100463. [PMID: 38591050 PMCID: PMC11000102 DOI: 10.1016/j.xops.2023.100463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/01/2023] [Accepted: 12/26/2023] [Indexed: 04/10/2024]
Abstract
Purpose To determine the correlation between blood flow metrics measured by intravenous fluorescein angiography (IVFA) and the blood flow velocity index (BFVi) obtained by laser speckle contrast imaging (LSCI) in infants with retinopathy of prematurity (ROP). Design Prospective comparative pilot study. Subjects Seven eyes from 7 subjects with ROP. Methods Unilateral LSCI and IVFA data were obtained from each subject in the neonatal intensive care unit. Five LSCI-based metrics and 5 IVFA-based metrics were extracted from images to quantify blood flow patterns in the same region of interest. Correlation between LSCI-based and IVFA-based blood flow metrics was compared between 2 subgroups of ROP severity: moderate ROP (defined as stage ≤ 2 without Plus disease) and severe ROP (defined as stage ≥3 or Plus disease). Main Outcome Measures Pearson and Kendall rank correlation coefficients between IVFA and LSCI metrics; Student t test P values comparing LSCI metrics between "severe" and "moderate" ROP groups. Results Pearson correlations between IVFA and LSCI included arterial-venous transit time (AVTT) and peak BFVi (pBFVi; r = -0.917; P = 0.004), AVTT and dip BFVi (dBFVi; r = -0.920; P = 0.003), AVTT and mean BFVi (r = -0.927- P = 0.003), and AVTT and volumetric rise index (r = -0.779; P = 0.039). Kendall rank correlation between AVTT and dBFVi was r = -0.619 (P = 0.051). pBFVi was higher in severe ROP than in moderate ROP (8.4 ± 0.6 and 4.4 ± 1.8, respectively; P = 0.0045 using the 2-sample t test with pooled variance and P = 0.0952 using the Wilcoxon rank-sum test). Conclusions Correlation was found between blood flow metrics obtained by IVFA and noninvasive LSCI techniques. We demonstrate the feasibility of obtaining quantitative metrics using LSCI in infants with ROP in this pilot study; however, further investigation is needed to evaluate its potential use in clinical assessment of ROP severity. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Daniel Shats
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Tara Balasubramanian
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Danielle Sidelnikov
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Urjita Das
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Ndidi-Amaka Onyekaba
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - He E. Forbes
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Noela Lu
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kristin Williams
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Moran R. Levin
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Sripriya Sundararajan
- Department of Neonatology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Shitiz Vij
- Vasoptic Medical, Inc., Columbia, Maryland
| | | | | | - Osamah Saeedi
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Victoria Chen
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Janet L. Alexander
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland
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Cho E, Das U, Sidelnikov D, Balasubramanian T, Shats D, Mansoor S, Forbes HE, Zhou J, Kapoor R, Chase S, Kore M, Williams K, Saeedi O, Sundararajan S, Levin MR, Magder L, Alexander J. Retinal blood flow association with age and weight in infants at risk for retinopathy of prematurity. Res Sq 2024:rs.3.rs-3909449. [PMID: 38464120 PMCID: PMC10925429 DOI: 10.21203/rs.3.rs-3909449/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
This prospective study evaluated the relationship between laser speckle contrast imaging (LSCI) ocular blood flow velocity (BFV) and five birth parameters: gestational age (GA), postmenstrual age (PMA), and chronological age (CA) at the time of measurement, birth weight (BW), and current weight (CW) in preterm neonates at risk for retinopathy of prematurity (ROP).38 Neonates with BW < 2 kg, GA < 32 weeks, and PMA between 27-47 weeks underwent 91 LSCI sessions. Correlation tests and regression analysis were performed to quantify relationships between birth parameters and ocular BFV. Mean ocular BFV index in this cohort was 8.8 +/- 4.0 IU. BFV positively correlated with PMA (r = 0.3, p = 0.01), CA (r = 0.3, p = 0.005), and CW (r = 0.3, p = 0.02). BFV did not correlate with GA nor BW (r=-0.2 and r=-0.05, p > 0.05). Regression analysis with mixed models demonstrated that BFV increased by 1.2 for every kilogram of CW, by 0.34 for every week of CA, and by 0.36 for every week of PMA (p = 0.03, 0.004, 0.007, respectively). Our findings indicate that increased age and weight are associated with increased ocular BFV measured using LSCI in premature infants. Future studies investigating the associations between ocular BFV and ROP clinical severity must control for age and/or weight of the infant.
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Affiliation(s)
- Euna Cho
- University of Maryland School of Medicine
| | - Urjita Das
- University of Maryland School of Medicine
| | | | | | | | | | | | - Jason Zhou
- University of Maryland School of Medicine
| | - Ria Kapoor
- University of Maryland School of Medicine
| | - Sera Chase
- University of Maryland School of Medicine
| | - Madi Kore
- University of Maryland School of Medicine
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Diviya M, Joel JJ, Subramanian M, Balasubramanian T, Madhusuthan AV, Monish N, Hasan N. Parametric investigation of W-EDM factors for machining AM60B conductive biomaterial. Sci Rep 2024; 14:216. [PMID: 38168764 PMCID: PMC10761742 DOI: 10.1038/s41598-023-50777-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 12/25/2023] [Indexed: 01/05/2024] Open
Abstract
Wire-electrical discharge machining (W-EDM) is a precise and efficient non-traditional technology employed to cut intricate shapes in conductive biomaterials. These biomaterials are challenging to machine using traditional methods. This present study delves into the impact of various process parameters, namely discharge duration (Ddur), spark gap time (Stime), discharge voltage (Dvolt), and wire advance rate rate (Wadv). This research evaluates the impact of several factors on response variables, namely the machining rate (MR) and surface irregularity (SR), during the machining process of the AM60B magnesium alloy. The confirmation of the material used in the machining process is achieved via the utilisation of a scanning electron microscopy (SEM) image in conjunction with an energy dispersive spectroscopic (EDS) image. The experiment is designed as L9 orthogonal array by using Taguchi's approach, taking into account 4 factors with 3 levels. The objective of this experiment is to ascertain the most favourable values for machining parameters while working with AM60B magnesium alloy using brass wire. Through analysis of variance (ANOVA), the study confirms that wire advance rate (43.10%) is the most influencing parameter for machining rate and surface irregularity followed by spark gap time (33.91%) and discharge duration (11.48%). Additionally, The TOPSIS-CRITIC and the desirability approach were used in order to determine the optimum parameter combinations that provide the most favourable combined output. Confirmatory testing is used to evaluate the efficiency of the stated ideal conditions. The maximum improvement in Desirability approach is obtained at 4.56% and 4.193% for MR and SR respectively. The maximum improvement in TOPSIS approach is obtained at 1.77% and 2.78% for MR and SR respectively.
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Affiliation(s)
- M Diviya
- Department of Computer Science and Engineering, Amrita School of Computing, Amrita Vishwa Vidyapeetham - Chennai Campus, Chennai, Tamil Nadu, 601103, India
| | - J Jebin Joel
- Department of Mechanical Engineering, St. Joseph's College of Engineering, Old Mamallapuram Road, Chennai, Tamil Nadu, 600119, India
| | - M Subramanian
- Department of Mechanical Engineering, St. Joseph's College of Engineering, Old Mamallapuram Road, Chennai, Tamil Nadu, 600119, India
| | - T Balasubramanian
- Department of Mechanical Engineering, St. Joseph's College of Engineering, Old Mamallapuram Road, Chennai, Tamil Nadu, 600119, India
| | - A V Madhusuthan
- Department of Mechanical Engineering, St. Joseph's College of Engineering, Old Mamallapuram Road, Chennai, Tamil Nadu, 600119, India
| | - N Monish
- Department of Mechanical Engineering, St. Joseph's College of Engineering, Old Mamallapuram Road, Chennai, Tamil Nadu, 600119, India
| | - Nasim Hasan
- Department of Mechanical Engineering, College of Engineering and Technology, Mettu University, Mettu, Oromia, Ethiopia.
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Polley CM, Fedderwitz H, Balasubramanian T, Zakharov AA, Yakimova R, Bäcke O, Ekman J, Dash SP, Kubatkin S, Lara-Avila S. Bottom-Up Growth of Monolayer Honeycomb SiC. Phys Rev Lett 2023; 130:076203. [PMID: 36867809 DOI: 10.1103/physrevlett.130.076203] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 12/22/2022] [Indexed: 06/18/2023]
Abstract
The long theorized two-dimensional allotrope of SiC has remained elusive amid the exploration of graphenelike honeycomb structured monolayers. It is anticipated to possess a large direct band gap (2.5 eV), ambient stability, and chemical versatility. While sp^{2} bonding between silicon and carbon is energetically favorable, only disordered nanoflakes have been reported to date. Here we demonstrate large-area, bottom-up synthesis of monocrystalline, epitaxial monolayer honeycomb SiC atop ultrathin transition metal carbide films on SiC substrates. We find the 2D phase of SiC to be almost planar and stable at high temperatures, up to 1200 °C in vacuum. Interactions between the 2D-SiC and the transition metal carbide surface result in a Dirac-like feature in the electronic band structure, which in the case of a TaC substrate is strongly spin-split. Our findings represent the first step towards routine and tailored synthesis of 2D-SiC monolayers, and this novel heteroepitaxial system may find diverse applications ranging from photovoltaics to topological superconductivity.
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Affiliation(s)
- C M Polley
- MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - H Fedderwitz
- MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden
| | - T Balasubramanian
- MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden
| | - A A Zakharov
- MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden
| | - R Yakimova
- Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, 581 83 Sweden
| | - O Bäcke
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - J Ekman
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - S P Dash
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - S Kubatkin
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - S Lara-Avila
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
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5
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Prasanth N, Pandian P, Balasubramanian T. Role of NMDA Receptors in Alzheimer's Disease Pathology and Potential NMDA Receptor Blockers from Medicinal Plants - A Review. AJPRHC 2021. [DOI: 10.18311/ajprhc/2021/28351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
<p>Alzheimer’s disease is responsible for 60-70 percent of dementia cases worldwide. Globally, there are 24.3 million cases. Researchers have attempted to develop multi-target medications to suppress several mechanisms in Alzheimer’ Disease, like protein mis-folding and related beta amyloid aggregation, oxidative stress, and decreasing Acetyl choline levels. NMDA-mediated neurotoxicity is often linked to cognitive impairment, as shown in Alzheimer’s disease. NMDA receptors found to have to connection with beta amyloid peptide and tau protein deposition which are major characteristics of Alzheimer’s disease. NMDA receptor antagonists are a viable therapy option for a many neurological disorders, as well as Alzheimer’s disease. Currently, majority of the drugs used in the management of Alzheimer’s disease are Acetyl choline Esterase inhibitors. Memantine is the only approved NMDA blocker, to be used in Alzheimer’s disease, which is found to be effective only to a certain extend. There is a need for better therapeutic agents belonging to this class. This paper intends to provide a rapid reference about the involvement of NMDA receptors in the pathogenesis of Alzheimer’s disease, as well as phyto constituents that have been identified to inhibit NMDA receptors.</p>
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6
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Gnanaraj J, Sindhu E, Nandakumaran M, Veeramani R, Kannan K, Anne Princy S, Cecily Mary M, Arumugam MA, Kannan P, Sabapathy K, Swaminathan N, Senthil Kumar G, Nambirajan N, Balasubramanian T, Ravichandran Edwin JM. Impact of COVID-19 pandemic on a developing STEMI care system from a low-middle income country- a prospective observational study. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
COVID-19 pandemic has produced a great impact in the STEMI (ST Elevation Myocardial Infarction) care systems across the world. Patient hesitancy to seek medical attention for suspected STEMI, necessity of the health care systems to prioritize COVID-19 care, safety concerns of health care workers etc., have brought in unprecedented times for both patients and health care workers. The impact of COVID-19 pandemic on the establishment of a STEMI care system is less known
Purpose
To identify the impact of COVID-19 pandemic on a developing public STEMI care system in a low-middle income country in Asia, with reference to the type of reperfusion offered and outcome.
Methods
Data on number of STEMI admissions, type of reperfusion therapy and outcome are being collected from 12 teaching hospitals as a part of a developing public regional STEMI care system based on a hub and spoke model in a low middle-income country from August 2018. These 12 “thrombolysis only” hospitals were being upgraded as “primary percutaneous coronary intervention (PPCI) capable hub hospitals” in 2019. Though the hassles of COVID-19 pandemic affected this process significantly, daily data collection in our STEMI care system continued. The maximal COVID impacted period in 2020 was identified from the online database (1) as from April to December 2020. The number, type of reperfusion and outcome of the STEMI patients treated during this period were compared to the same data collected during April-December 2019.
Results
A total of 13,137 STEMI patients were treated in our system during the two time periods “April to December 2019” and “April to December 2020”. There was a 13.3% drop in the number of STEMI treated in 2020, compared to the number treated in 2019 (6101 vs 8925; P<0.001). This drop was in proportion to the number of new cases of COVID-19 reported in our state (Fig. 1a)
We also noted a significant drop in the rate of PPCI and Pharmaco-invasive therapy (PIT) offered for STEMI in 2020 compared to 2019 in the same period (PPCI: 0.13% vs 5.9%-P<0.001 and PIT 0.64% vs 11%- P<0.001). This decrease in PPCI and PIT for STEMI also corresponded to the increase in number of new cases of COVID-19 reported (Fig. 1b). More patients received thrombolytic therapy for STEMI in 2020 compared to 2019 (73.6 vs 61.2% P<0.001). There was no change in the mortality of STEMI during this period. (Fig. 2)
Conclusion
We found a significant drop in number of patients seeking medical care for STEMI during COVID-19 pandemic. There was significant drop in the rate of PPCI and PIT offered in our STEMI care system. Thrombolytic therapy remained the predominant mode of reperfusion as before, but with a significant increased rate of thrombolysis. There was no change in mortality rate in STEMI patients. Thrombolytic therapy is an acceptable mode of reperfusion, when the balance of a STEMI care system is disturbed by extraneous influences like the COVID-19 pandemic.
Funding Acknowledgement
Type of funding sources: Public hospital(s). Main funding source(s): Tamil Nadu Innovation Initiative- Department of Planning and development, Govt of Tamil NaduNational Health Mission, Government of India
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Affiliation(s)
| | - E Sindhu
- Madras Medical College, Chennai, India
| | | | | | - K Kannan
- Stanley Medical College, Chennai, India
| | - S Anne Princy
- Tamil Nadu Government Multi Super Speciality Hospital, Chennai, India
| | - M Cecily Mary
- Tamil Nadu Government Multi Super Speciality Hospital, Chennai, India
| | - M A Arumugam
- Chengalpattu Medical College, Chengalpattu, India
| | - P Kannan
- Governnment MKM Medical College, Salem, India
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7
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Mao B, Wang Y, Balasubramanian T, Urioste R, Wafa T, Fitzgerald TS, Haraczy SJ, Edwards-Hollingsworth K, Sayyid ZN, Wilder D, Sajja VSSS, Wei Y, Arun P, Gist I, Cheng AG, Long JB, Kelley MW. Assessment of auditory and vestibular damage in a mouse model after single and triple blast exposures. Hear Res 2021; 407:108292. [PMID: 34214947 DOI: 10.1016/j.heares.2021.108292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/17/2021] [Accepted: 06/02/2021] [Indexed: 12/18/2022]
Abstract
The use of explosive devices in war and terrorism has increased exposure to concussive blasts among both military personnel and civilians, which can cause permanent hearing and balance deficits that adversely affect survivors' quality of life. Significant knowledge gaps on the underlying etiology of blast-induced hearing loss and balance disorders remain, especially with regard to the effect of blast exposure on the vestibular system, the impact of multiple blast exposures, and long-term recovery. To address this, we investigated the effects of blast exposure on the inner ear using a mouse model in conjunction with a high-fidelity blast simulator. Anesthetized animals were subjected to single or triple blast exposures, and physiological measurements and tissue were collected over the course of recovery for up to 180 days. Auditory brainstem responses (ABRs) indicated significantly elevated thresholds across multiple frequencies. Limited recovery was observed at low frequencies in single-blasted mice. Distortion Product Otoacoustic Emissions (DPOAEs) were initially absent in all blast-exposed mice, but low-amplitude DPOAEs could be detected at low frequencies in some single-blast mice by 30 days post-blast, and in some triple-blast mice at 180 days post-blast. All blast-exposed mice showed signs of Tympanic Membrane (TM) rupture immediately following exposure and loss of outer hair cells (OHCs) in the basal cochlear turn. In contrast, the number of Inner Hair Cells (IHCs) and spiral ganglion neurons was unchanged following blast-exposure. A significant reduction in IHC pre-synaptic puncta was observed in the upper turns of blast-exposed cochleae. Finally, we found no significant loss of utricular hair cells or changes in vestibular function as assessed by vestibular evoked potentials. Our results suggest that (1) blast exposure can cause severe, long-term hearing loss which may be partially due to slow TM healing or altered mechanical properties of healed TMs, (2) traumatic levels of sound can still reach the inner ear and cause basal OHC loss despite middle ear dysfunction caused by TM rupture, (3) blast exposure may result in synaptopathy in humans, and (4) balance deficits after blast exposure may be primarily due to traumatic brain injury, rather than damage to the peripheral vestibular system.
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Affiliation(s)
- Beatrice Mao
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA.
| | - Ying Wang
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - Tara Balasubramanian
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Rodrigo Urioste
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Talah Wafa
- Mouse Auditory Testing Core Facility, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Tracy S Fitzgerald
- Mouse Auditory Testing Core Facility, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Scott J Haraczy
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Kamren Edwards-Hollingsworth
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
| | - Zahra N Sayyid
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Donna Wilder
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Venkata Siva Sai Sujith Sajja
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Yanling Wei
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Peethambaran Arun
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Irene Gist
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Alan G Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Joseph B Long
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| | - Matthew W Kelley
- Section on Developmental Neuroscience, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA
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Arivazhagan S, Rajasekar D, Gopalakrishnan N, Sakthirajan R, Dhanapriya J, Kumar TD, Balasubramanian T, Malathy N. Clinicopathological profile and outcome of adult infection-related glomerulonephritis: A prospective follow-up study. Natl Med J India 2020; 33:260-264. [PMID: 34213450 DOI: 10.4103/0970-258x.317465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background . Infection-related glomerulonephritis (IRGN) in adults is witnessing a dramatic shift in its epidemiology and outcome. Adult IRGN studies are all retrospective in nature, and Indian studies are scarce. Methods . We did this prospective study (September 2016-April 2018) on all patients with biopsy-proven IRGN and age ≥18 years satisfying three of five diagnostic criteria. Patients with persistent hypocomplementaemia (>3 months) were excluded. We did electron microscopy in those without a minimum of three diagnostic criteria and did an extensive search for any occult infection in every patient. Results . Forty-five patients were studied with a mean (SD) follow-up of 45.7 (20) weeks. Their mean age was 41.5 years (18-70 years), with a female preponderance (1:1.25). At presentation, the majority had oedema (100%), oliguria (84.4%), hypertension (80%) and haematuria (77.8%). Of them, 86.7% had renal insufficiency and 35.6% required dialysis. Only 53.3% of them had evidence of antecedent/ current infection, with skin/subcutaneous focus being the most common site. Hypocomplementaemia was present in 82.2% of patients. Salient pathological features were endocapillary proliferation (93.3%), neutrophilic infiltration (88.9%), presence of crescents (17.8%), interstitial infiltration (24.4%), moderate-to-severe interstitial fibrosis with tubular atrophy (IFTA; 15.5%) and underlying diabetic glomerulosclerosis (8.9%). Only 66.7% of patients made complete renal recovery. By logistic regression analysis, the predictors of poor outcome were a requirement for dialysis at presentation (p=0.04) and presence of IFTA (p = 0.03). Conclusion . A proportion of adult IRGN patients progress to chronic kidney disease.
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Affiliation(s)
- S Arivazhagan
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - D Rajasekar
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - N Gopalakrishnan
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - R Sakthirajan
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - J Dhanapriya
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - T Dinesh Kumar
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - T Balasubramanian
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
| | - N Malathy
- Department of Nephrology, Institute of Nephrology, Madras Medical College, Park Town, Chennai 600009, Tamil Nadu, India
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Kaleeswaran B, Ramadevi S, Murugesan R, Srigopalram S, Suman T, Balasubramanian T. Evaluation of anti-urolithiatic potential of ethyl acetate extract of Pedalium murex L. on struvite crystal (kidney stone). J Tradit Complement Med 2019; 9:24-37. [PMID: 30671363 PMCID: PMC6335495 DOI: 10.1016/j.jtcme.2017.08.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 05/16/2017] [Accepted: 08/01/2017] [Indexed: 11/25/2022] Open
Abstract
Pedalium murex (L.) is a traditional herb, commonly used for the treatment of kidney stone related problems. Struvite stone can swiftly grow and become 'staghorn calculi' in kidney and its associated areas, which is the most aching urological disorder. The present study investigated the anti-urolithiasis activities of ethyl acetate extract of P. murex L. (EAEP) against struvite crystal. The antibacterial activity of EAEP examined against several urease producing bacteria. It showed the minimum bactericidal concentration (MBC) against Escherichia coli and Staphylococcus aureus (>125). On the other hand, total mass, volume, number, growth rate and dissolution rate of synthesised struvite crystals were observed at different concentrations 0.5%, 0.75%, 1% of EAEP and without EAEP. In which, EAEP addition showed appreciably reduced struvite crystal. Alternatively, MgO (300 mg of EAEP/kg/body weight) induced urolithiasis of Wistar albino rat at the rate of 1 ml for 28 days. Various biochemical parameters in serum, urine and histological analysis of kidney were taken for evaluation. Significant results (p < 0.05) were observed in 1% EAEP (300 mg) treated group than cystone treated group. From the histological study, reduced renal damage and glomerular development were observed. Our experiment, P. murex L. enhances the reducing activity on struvite crystal and prevents the crystal formation both in-vitro and in-vivo. It can be suggesting that P. murex L. and its phyto-components could be used as remedy for the management of kidney stone by dissolving the struvite stone in kidney.
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Affiliation(s)
- B Kaleeswaran
- Department of Zoology and Biotechnology, A.V.V.M. Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India
| | - S Ramadevi
- Department of Zoology and Biotechnology, A.V.V.M. Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India
| | - R Murugesan
- Department of Zoology and Biotechnology, A.V.V.M. Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India
| | - S Srigopalram
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan, South Korea
| | - T Suman
- Department of Botany, Bharathiar University, Coimbatore, Tamil Nadu, India
| | - T Balasubramanian
- Department of Pharmacology, Al Shifa College of Pharmacy, Poonthavanam Post, Kizhattur Village, Perinthalmanna, Malappuram Dist, Kerala, India
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Thirugnanasambandam R, Inbakandan D, Kumar C, Subashni B, Vasantharaja R, Stanley Abraham L, Ayyadurai N, Sriyutha Murthy P, Kirubagaran R, Ajmal Khan S, Balasubramanian T. Genomic insights of Vibrio harveyi RT-6 strain, from infected “Whiteleg shrimp” (Litopenaeus vannamei) using Illumina platform. Mol Phylogenet Evol 2019; 130:35-44. [DOI: 10.1016/j.ympev.2018.09.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
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Shanthi PMS, Ashok M, Uthirakumar P, Balasubramanian T. Influence of Bicationic and Catanionic Surfactants Over the Morphology of Mesoporous Nanohydroxyapatite. J Nanosci Nanotechnol 2018; 18:7064-7071. [PMID: 29954534 DOI: 10.1166/jnn.2018.15517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the co-precipitation method, the morphology of nano Hydroxyapatite (HAp) is usually being controlled by parameters like pH, temperature, concentration, and the ratio of the mixed surfactants. In the present work, effective tailoring of morphology has been done by exploiting the electrostatic interaction between surfactants by grouping them as catanionic (Cetrimide and SDS) and bicationic (Cetrimide and CTAB), with weight ratio of 1:1 and total concentration of 0.28 g/100 ml. The prepared samples were subjected to various characterizations like FTIR, XRD, FESEM, HRTEM, TGA/DTA, and BET analysis. The results show that the samples are in HAp phase, nano size and mesoporous in nature. The FESEM images reveal the fact that the catanionic surfactant enhances the growth of particle from sphere to hexagonal rod whereas bicationic mixture suppresses the growth and results in a disk-like HAp. The samples were subjected to AAS test for finding the Ca2+ ion release rate in SBF and were compared with a commercial nanocrystalline HAp sample. The Ca2+ ion release test of the samples shows signs of better bioactivity of disk-like HAp than that of commercial one.
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Bahramy MS, Clark OJ, Yang BJ, Feng J, Bawden L, Riley JM, Marković I, Mazzola F, Sunko V, Biswas D, Cooil SP, Jorge M, Wells JW, Leandersson M, Balasubramanian T, Fujii J, Vobornik I, Rault JE, Kim TK, Hoesch M, Okawa K, Asakawa M, Sasagawa T, Eknapakul T, Meevasana W, King PDC. Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides. Nat Mater 2018; 17:21-28. [PMID: 29180775 DOI: 10.1038/nmat5031] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 10/13/2017] [Indexed: 05/12/2023]
Abstract
Transition-metal dichalcogenides (TMDs) are renowned for their rich and varied bulk properties, while their single-layer variants have become one of the most prominent examples of two-dimensional materials beyond graphene. Their disparate ground states largely depend on transition metal d-electron-derived electronic states, on which the vast majority of attention has been concentrated to date. Here, we focus on the chalcogen-derived states. From density-functional theory calculations together with spin- and angle-resolved photoemission, we find that these generically host a co-existence of type-I and type-II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. We demonstrate how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across a large number of compounds. Already, we demonstrate their existence in six separate TMDs, opening routes to tune, and ultimately exploit, their topological physics.
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Affiliation(s)
- M S Bahramy
- Quantum-Phase Electronics Center and Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
- RIKEN center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
| | - O J Clark
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
| | - B-J Yang
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul 08826, Korea
- Center for Theoretical Physics (CTP), Seoul National University, Seoul 08826, Korea
| | - J Feng
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
- Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) CAS, 398 Ruoshi Road, SEID, SIP, Suzhou 215123, China
| | - L Bawden
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
| | - J M Riley
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - I Marković
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - F Mazzola
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
| | - V Sunko
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - D Biswas
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
| | - S P Cooil
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - M Jorge
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - J W Wells
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - M Leandersson
- MAX IV Laboratory, Lund University, PO Box 118, 221 00 Lund, Sweden
| | | | - J Fujii
- Istituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, in Area Science Park, S.S.14, Km 163.5, I-34149 Trieste, Italy
| | - I Vobornik
- Istituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, in Area Science Park, S.S.14, Km 163.5, I-34149 Trieste, Italy
| | - J E Rault
- Synchrotron SOLEIL, CNRS-CEA, L'Orme des Merisiers, Saint-Aubin-BP48, 91192 Gif-sur-Yvette, France
| | - T K Kim
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - M Hoesch
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - K Okawa
- Laboratory for Materials and Structures, Tokyo Institute of Technology, Kanagawa 226-8503, Japan
| | - M Asakawa
- Laboratory for Materials and Structures, Tokyo Institute of Technology, Kanagawa 226-8503, Japan
| | - T Sasagawa
- Laboratory for Materials and Structures, Tokyo Institute of Technology, Kanagawa 226-8503, Japan
| | - T Eknapakul
- School of Physics and Center of Excellence on Advanced Functional Materials, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - W Meevasana
- School of Physics and Center of Excellence on Advanced Functional Materials, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
- ThEP, Commission of Higher Education, Bangkok 10400, Thailand
| | - P D C King
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK
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Thirugnanasambandam R, Inbakandan D, Abraham LS, Kumar C, Sundaram S, Subashni B, Vasantharaja R, Anantha Kumar AA, Kirubagaran R, Khan SA, Balasubramanian T. De novo assembly and annotation of the whole genomic analysis of Vibrio campbellii RT-1 strain, from infected shrimp: Litopenaeus vannamei. Microb Pathog 2017; 113:372-377. [DOI: 10.1016/j.micpath.2017.11.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/04/2017] [Accepted: 11/09/2017] [Indexed: 10/18/2022]
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Bentmann H, Maaß H, Krasovskii EE, Peixoto TRF, Seibel C, Leandersson M, Balasubramanian T, Reinert F. Strong Linear Dichroism in Spin-Polarized Photoemission from Spin-Orbit-Coupled Surface States. Phys Rev Lett 2017; 119:106401. [PMID: 28949177 DOI: 10.1103/physrevlett.119.106401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Indexed: 06/07/2023]
Abstract
A comprehensive understanding of spin-polarized photoemission is crucial for accessing the electronic structure of spin-orbit coupled materials. Yet, the impact of the final state in the photoemission process on the photoelectron spin has been difficult to assess in these systems. We present experiments for the spin-orbit split states in a Bi-Ag surface alloy showing that the alteration of the final state with energy may cause a complete reversal of the photoelectron spin polarization. We explain the effect on the basis of ab initio one-step photoemission theory and describe how it originates from linear dichroism in the angular distribution of photoelectrons. Our analysis shows that the modulated photoelectron spin polarization reflects the intrinsic spin density of the surface state being sampled differently depending on the final state, and it indicates linear dichroism as a natural probe of spin-orbit coupling at surfaces.
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Affiliation(s)
- H Bentmann
- Experimentelle Physik VII and Röntgen Research Center for Complex Materials (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - H Maaß
- Experimentelle Physik VII and Röntgen Research Center for Complex Materials (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - E E Krasovskii
- Departamento de Física de Materiales, Facultad de Ciencias Quíimicas, Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Apdo. 1072, San Sebastián/Donostia, 20080 Basque Country, Spain
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián/Donostia, 20018 Basque Country, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - T R F Peixoto
- Experimentelle Physik VII and Röntgen Research Center for Complex Materials (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - C Seibel
- Experimentelle Physik VII and Röntgen Research Center for Complex Materials (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - M Leandersson
- MAX IV Laboratory, Lund University, P.O. Box 118, 221 00 Lund, Sweden
| | - T Balasubramanian
- MAX IV Laboratory, Lund University, P.O. Box 118, 221 00 Lund, Sweden
| | - F Reinert
- Experimentelle Physik VII and Röntgen Research Center for Complex Materials (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
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Nayana S, Balasubramanian T, Nathaliya P, Nimsha Hussain P, Mohammed Salim K, Muhammed Lubab P. A cross sectional study on assessment of health related quality of life among end stage renal disease patients undergoing hemodialysis. Clinical Epidemiology and Global Health 2017. [DOI: 10.1016/j.cegh.2016.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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16
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Balasubramanian T, Karthikeyan M, Muhammed Anees KP, Kadeeja CP, Jaseela K. Antidiabetic and Antioxidant Potentials of Amaranthus hybridus in Streptozotocin-Induced Diabetic Rats. J Diet Suppl 2017; 14:395-410. [PMID: 28129002 DOI: 10.1080/19390211.2016.1265037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
CONTEXT Amaranthus hybridus (Amaranthaceae) has been used as a folk medicine in southern parts of India for the treatment of diabetes. OBJECTIVE This research evaluates the antidiabetic and antioxidant effects of Amaranthus hybridus ethanol leaf extract (AHELE) in streptozotocin-induced diabetic rats. METHODS Blood glucose levels of diabetic rats were measured on days 1, 4, 7, and 15 after oral administration of AHELE at doses of 200 and 400 mg/kg for 14 days. The effects of extract were observed on serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, serum alkaline phosphatase, cholesterol, high- and low-density lipoprotein, antioxidant potential, and histopathological changes. RESULT AHELE (200 and 400 mg/kg) caused a significant (p < 0.001) reduction in blood glucose levels on day 15 (152.2 and 181.2 mg/dL, respectively versus diabetic control 287.0 mg/dL). The extract also improved serum biochemical parameters associated with diabetes. A significant (p < 0.001) decrease in malondialdehyde protein (liver: 15.92, 12.29 nmol/mg, and kidney: 13.92, 10.29 nmol/mg vs. diabetic control 25.49, 24.49 nmol/mg), increase in superoxide dismutase protein (14.01; 17.47 IU/mg, and 25.01; 37.47 IU/mg vs. diabetic control 9.65; 15.65 IU/mg), catalase protein (35.80, 44.49, and 39.80, 49.69 nmol/min/mg vs. diabetic control 18.45, 20.85 nmol/min/mg) and reduced glutathione protein (44.77, 55.08 and 40.77, 51.08 μM/gm vs. diabetic control 29.81, 26.50 μM/gm) were observed. CONCLUSIONS The study reveals that treatment of diabetic rats with AHELE significantly reduced hyperglycemia-associated oxidative damage. This could provide a rationale for the use of the plant to treat diabetes in folk medicine.
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Affiliation(s)
- T Balasubramanian
- a Department of Pharmacology , Al Shifa College of Pharmacy , Kerala , India
| | - M Karthikeyan
- a Department of Pharmacology , Al Shifa College of Pharmacy , Kerala , India
| | - K P Muhammed Anees
- a Department of Pharmacology , Al Shifa College of Pharmacy , Kerala , India
| | - C P Kadeeja
- a Department of Pharmacology , Al Shifa College of Pharmacy , Kerala , India
| | - K Jaseela
- a Department of Pharmacology , Al Shifa College of Pharmacy , Kerala , India
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Surendar D, Dineshkumar T, Dhanapriya J, Sakthirajan R, Balasubramanian T, Gopalakrishnan N. Deceased donor renal transplant graft survival – A single center experience. Indian Journal of Transplantation 2016. [DOI: 10.1016/j.ijt.2016.09.077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Logan JA, Patel SJ, Harrington SD, Polley CM, Schultz BD, Balasubramanian T, Janotti A, Mikkelsen A, Palmstrøm CJ. Observation of a topologically non-trivial surface state in half-Heusler PtLuSb (001) thin films. Nat Commun 2016; 7:11993. [PMID: 27346655 PMCID: PMC4931221 DOI: 10.1038/ncomms11993] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 05/16/2016] [Indexed: 11/30/2022] Open
Abstract
The discovery of topological insulators, materials with bulk band gaps and protected cross-gap surface states in compounds such as Bi2Se3, has generated much interest in identifying topological surface states (TSSs) in other classes of materials. In particular, recent theoretical calculations suggest that TSSs may be found in half-Heusler ternary compounds. If experimentally realizable, this would provide a materials platform for entirely new heterostructure spintronic devices that make use of the structurally identical but electronically varied nature of Heusler compounds. Here we show the presence of a TSS in epitaxially grown thin films of the half-Heusler compound PtLuSb. Spin- and angle-resolved photoemission spectroscopy, complemented by theoretical calculations, reveals a surface state with linear dispersion and a helical tangential spin texture consistent with previous predictions. This experimental verification of topological behaviour is a significant step forward in establishing half-Heusler compounds as a viable material system for future spintronic devices.
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Affiliation(s)
- J. A. Logan
- Materials Department, University of California-Santa Barbara, Santa Barbara, California 93106, USA
| | - S. J. Patel
- Materials Department, University of California-Santa Barbara, Santa Barbara, California 93106, USA
| | - S. D. Harrington
- Materials Department, University of California-Santa Barbara, Santa Barbara, California 93106, USA
| | - C. M. Polley
- MAX IV Laboratory, Lund University, Lund 221 00, Sweden
| | - B. D. Schultz
- Department of Electrical and Computer Engineering, University of California-Santa Barbara, Santa Barbara, California 93106, USA
| | | | - A. Janotti
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - A. Mikkelsen
- Department of Physics, Lund University, Lund 221 00, Sweden
| | - C. J. Palmstrøm
- Materials Department, University of California-Santa Barbara, Santa Barbara, California 93106, USA
- Department of Electrical and Computer Engineering, University of California-Santa Barbara, Santa Barbara, California 93106, USA
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Balakrishnan T, Sundaramanickam A, Shekhar S, Muthukumaravel K, Balasubramanian T. Seasonal abundance and distribution of ichthyoplankton diversity in the Coleroon estuarine complex, Southeast coast of India. Biocatalysis and Agricultural Biotechnology 2015. [DOI: 10.1016/j.bcab.2015.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Dhayanithi NB, Kumar TTA, Kalaiselvam M, Balasubramanian T, Sivakumar N. Anti-dermatophytic activity of marine sponge, Sigmadocia carnosa (Dendy) on clinically isolated fungi. Asian Pac J Trop Biomed 2015; 2:635-9. [PMID: 23569985 DOI: 10.1016/s2221-1691(12)60111-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 01/23/2012] [Accepted: 03/12/2012] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To screen the anti-fungal effects and find out the active metabolites from sponge, Sigmadocia carnosa (S. carnosa) against four dermatophytic fungi. METHODS The methanol, ethyl acetate and acetone extract of marine sponge, S. carnosa was examined against Trichophyton mentagrophytes (T. mentagrophytes), Trichophyton rubrum (T. rubrum), Epidermophyton floccosum (E. floccosum) and Microsporum gypseum (M. gypseum) and qualitative analysed to find out the active molecules. RESULTS The methanol extract of sponge was expressed significant activity than ethyl acetate and acetone. The minimum inhibitory concentration (MIC) of methanol extract of sponge that resulted in complete growth inhibition of T. mentagrophytes, T. rubrum, E. floccosum and M. gypseum were found to 125, 250, 250 and 250 µg/mL respectively. But, 100 % inhibition of fungal spore germination was observed in T. mentagrophytes at 500 µg/mL concentration followed by T. rubrum, E. floccosum and M. gypseum at 1 000 µg/mL concentration. Other two extracts showed weak anti spore germination activity against the tested dermatophytic fungi. Methanol extracts showed presence of terpenoids, steroids, alkaloids, saponins and glycosides. CONCLUSION Based on the literature, this is the first study which has conducted to inhibit the growth and spore germination of dermatophytic fungi with S. carnosa. Further research also needs to purify and characterize the secondary metabolites from the sponge, S. carnosa for the valuable source of novel substances for future drug discovery.
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Affiliation(s)
- N B Dhayanithi
- Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai - 608 502, Tamil Nadu, India
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Umayaparvathi S, Meenakshi S, Vimalraj V, Arumugam M, Sivagami G, Balasubramanian T. Antioxidant activity and anticancer effect of bioactive peptide from enzymatic hydrolysate of oyster (Saccostrea cucullata). ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.bionut.2014.04.006] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Thirunavukkarasu P, Asha S, Ramanathan T, Balasubramanian T, Shanmogapriya R, Renugadevi G. In Vitro Hepatoprotective Activity of Isolated Fractions of Cressa Cretica. Pharm Chem J 2014. [DOI: 10.1007/s11094-014-1061-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Umayaparvathi S, Meenakshi S, Vimalraj V, Arumugam M, Balasubramanian T. Isolation and Structural Elucidation of Antioxidant Peptides from Oyster (Saccostrea cucullata) Protein Hydrolysate. Protein Pept Lett 2014; 21:1073-83. [DOI: 10.2174/0929866521666140417121616] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 04/02/2014] [Accepted: 04/10/2014] [Indexed: 11/22/2022]
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Umayaparvathi S, Arumugam M, Meenakshi S, Balasubramanian T. Antioxidant Properties of Protein Hydrolysate Obtained from OysterSaccostrea cucullata(Born, 1778). Journal of Aquatic Food Product Technology 2014. [DOI: 10.1080/10498850.2013.791740] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Mazzola F, Wells JW, Yakimova R, Ulstrup S, Miwa JA, Balog R, Bianchi M, Leandersson M, Adell J, Hofmann P, Balasubramanian T. Kinks in the σ band of graphene induced by electron-phonon coupling. Phys Rev Lett 2013; 111:216806. [PMID: 24313515 DOI: 10.1103/physrevlett.111.216806] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Indexed: 05/09/2023]
Abstract
Angle-resolved photoemission spectroscopy reveals pronounced kinks in the dispersion of the σ band of graphene. Such kinks are usually caused by the combination of a strong electron-boson interaction and the cutoff in the Fermi-Dirac distribution. They are therefore not expected for the σ band of graphene that has a binding energy of more than ≈3.5 eV. We argue that the observed kinks are indeed caused by the electron-phonon interaction, but the role of the Fermi-Dirac distribution cutoff is assumed by a cutoff in the density of σ states. The existence of the effect suggests a very weak coupling of holes in the σ band not only to the π electrons of graphene but also to the substrate electronic states. This is confirmed by the presence of such kinks for graphene on several different substrates that all show a strong coupling constant of λ≈1.
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Affiliation(s)
- Federico Mazzola
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
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Vinothkumar R, Sudha M, Viswanathan P, Kabalimoorthy J, Balasubramanian T, Nalini N. Modulating effect of d-carvone on 1,2-dimethylhydrazine-induced pre-neoplastic lesions, oxidative stress and biotransforming enzymes, in an experimental model of rat colon carcinogenesis. Cell Prolif 2013; 46:705-20. [PMID: 24118219 DOI: 10.1111/cpr.12062] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 07/15/2013] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVES The present study has aimed to evaluate chemopreventive potential of d-carvone on oxidative stress markers, biotransforming enzymes, incidence of colonic polyps and aberrant crypt foci (ACF) in 1,2-dimethylhydrazine (DMH)-induced experimental colon carcinogenesis. MATERIALS AND METHODS Rats were randomly divided into six groups, with group I serving as control. Group II animals received d-carvone every day orally (20 mg/kg body weight) for 16 weeks; groups III-VI received subcutaneous injections of DMH (20 mg/kg body weight) once a week, for the first 4 weeks. In addition, groups IV-VI received different doses of d-carvone (5, 10 and 20 mg/kg body weight everyday orally) along with DMH injections. RESULTS Our results revealed that supplementation with d-carvone significantly reduced incidence of polyps/ACF and ACF multiplicity in DMH-exposed rats compared to DMH-alone-exposed rats. Moreover, our results showed reduced activities of liver and circulatory antioxidants and increased levels of lipid peroxidation by products in DMH-exposed animals, which were significantly reversed on supplementation with d-carvone. In addition, colonic antioxidants and lipid peroxidation were significantly diminished in DMH-exposed rats, which were significantly elevated on supplementation with d-carvone. Furthermore, we also determined activities of biotransforming enzymes, which were found to be altered in DMH-exposed rats, but reversed on d-carvone supplementation. All these observations of changes were supported by histochemical findings. CONCLUSION Overall, results obtained from this study suggest that d-carvone at 10 mg/kg body weight provided optimum protection and could be used as an effective chemopreventive agent against colon carcinogenesis induced by DMH.
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Affiliation(s)
- R Vinothkumar
- Faculty of Science, Department of Biochemistry and Biotechnology, Annamalai University, Chidambaram, Tamil Nadu, 608 002, India
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Dziawa P, Kowalski BJ, Dybko K, Buczko R, Szczerbakow A, Szot M, Łusakowska E, Balasubramanian T, Wojek BM, Berntsen MH, Tjernberg O, Story T. Topological crystalline insulator states in Pb(1-x)Sn(x)Se. Nat Mater 2012; 11:1023-1027. [PMID: 23023551 DOI: 10.1038/nmat3449] [Citation(s) in RCA: 185] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 09/07/2012] [Indexed: 06/01/2023]
Abstract
Topological insulators are a class of quantum materials in which time-reversal symmetry, relativistic effects and an inverted band structure result in the occurrence of electronic metallic states on the surfaces of insulating bulk crystals. These helical states exhibit a Dirac-like energy dispersion across the bulk bandgap, and they are topologically protected. Recent theoretical results have suggested the existence of topological crystalline insulators (TCIs), a class of topological insulators in which crystalline symmetry replaces the role of time-reversal symmetry in ensuring topological protection. In this study we show that the narrow-gap semiconductor Pb(1-x)Sn(x)Se is a TCI for x = 0.23. Temperature-dependent angle-resolved photoelectron spectroscopy demonstrates that the material undergoes a temperature-driven topological phase transition from a trivial insulator to a TCI. These experimental findings add a new class to the family of topological insulators, and we anticipate that they will lead to a considerable body of further research as well as detailed studies of topological phase transitions.
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Affiliation(s)
- P Dziawa
- Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw, Poland
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Haq MAB, Prabhuraj V, Vignesh R, Sedhuraman V, Srinivasan M, Balasubramanian T. Occurrence of white spot syndrome virus in shrimp culturing waters and its brunt in specific pathogen free Litopenaeus vannamei with particular allusion to molecular verdicts. Asian Pacific Journal of Tropical Disease 2012. [DOI: 10.1016/s2222-1808(12)60095-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Krishnakumar K, Franklin S, Prabhu GV, Balasubramanian T. 1,5-Dimethyl-2-phenyl-4-[phenyl(pyri-din-2-ylamino)methyl]-1H-pyrazol-3(2H)-one. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o3193. [PMID: 23284504 PMCID: PMC3515284 DOI: 10.1107/s1600536812042936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 10/15/2012] [Indexed: 11/11/2022]
Abstract
In the title compound, C(23)H(22)N(4)O, the pyrazole ring makes dihedral angles of 45.57 (11)° with the attached phenyl ring, and 83.98 (10) and 67.85 (10) °, respectively, with the other phenyl ring and the pyridyl ring. The pyridyl ring makes a dihedral angle of 80.15 (10)° with the adjacent phenyl ring. In the crystal, N-H⋯O hydrogen bonds supplemented by weak C-H⋯O hydrogen bonds link the mol-ecules into chains which run parallel to the a-axis direction.
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Affiliation(s)
- K Krishnakumar
- Department of Chemistry, National Institute of Technology, Tiruchirappalli 620 015, Tamilnadu, India
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Thangaradjou T, Sethubathi GV, Raja S, Poornima D, Shanthi R, Balasubramanian T, Babu K, Shukla A. Influence of environmental variables on phytoplankton floristic pattern along the shallow coasts of southwest Bay of Bengal. ALGAL RES 2012. [DOI: 10.1016/j.algal.2012.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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R.S R, R. Muduli P, Vishnu Vardhan K, Abhilash K, Paneer Selvam A, Charan Kumar B, Balasubramanian T. Assessment of Hydrogeochemical Characteristic in an Urbanized Estuary using Environmental Techniques. ACTA ACUST UNITED AC 2012. [DOI: 10.5923/j.geo.20120204.03] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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R. S R, Vishnu Vardhan K, R.Muduli P, Srinivasan M, Balasubramanian T. Preponderance of Enteric Pathogens Along the Coastal Waters of Southern Kerala, Southwest Coast of India. ACTA ACUST UNITED AC 2012. [DOI: 10.5923/j.ms.20120201.02] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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R. S R, R. Muduli P, Vishnu Vardhan K, Ganguly D, R Abhilash K, Balasubramanian T. Heavy Metal Contamination and Risk Assessment in the Marine Environment of Arabian Sea, along the Southwest Coast of India. ACTA ACUST UNITED AC 2012. [DOI: 10.5923/j.chemistry.20120204.03] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Murugesan P, Revathi K, Elayaraja S, Vijayalakshmi S, Balasubramanian T. Distribution of enteric bacteria in the sediments of Parangipettai and Cuddalore coast of India. J Environ Biol 2012; 33:705-711. [PMID: 23359995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Distribution of major groups of enteric bacteria viz., Escherichia coli, Shigella spp., Salmonella spp., Vibrio parahaemolyticus and Vibrio cholerae was studied in the sediment samples collected from different depths of 5, 15, 25 and 35 m in Parangipettai and Cuddalore coast during March, 2009 to February, 2010. Among the bacterial population in Parangipettai, V parahaemolyticus was found to be maximum with an occurrence of 55% followed by Shigella spp. (15%), V cholerae (12%), Salmonella spp. (12%) and E. coli (6%). In Cuddalore, as an oddity, Vibrio cholerae emerged as dominant species with an incidence of 60% of the total. V parahaemolyticus came next in the order with an incidence of 14%, followed by E. coli (11%), Shigella spp. (8%) and Salmonella spp. (7%). Similarly, monsoon and premonsoon seasons registered higher bacterial populations in both the regions. When the depth wise results were viewed, 5 and 15 m depths showed maximum (V parahaemolyticus 3.7 x 10 CFU g(-1) in Parangipettai; V cholera--8.6 x 10 CFU g(-1) in Cuddalore) bacterial population compared to subsequent depths. Cluster and MDS also showed distinct spatial and seasonal variations of bacterial populations in both the regions. Biota-Environment (BIO-ENV) method revealed the combinations of temperature, salinity and TOC as the best match influencing bacterial population.
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Affiliation(s)
- P Murugesan
- Centre ofAdvanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai--608 502, India.
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Kumar TTA, Gopi M, Dhaneesh KV, Vinoth R, Ghosh S, Balasubramanian T, Shunmugaraj T. Hatchery production of the clownfish Amphiprion nigripes at Agatti Island, Lakshadweep, India. J Environ Biol 2012; 33:623-628. [PMID: 23029913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Healthy individuals of matured clownfish, Amphiprion nigripes and sea anemone, Heteractis magnifica were collected from the Agatti island lagoon by snorkeling. During 'conditioning' for 3 months, pair formation occurred and the same were transferred to rectangular fiber glass spawning tanks of 10001 capacity. Suitable water quality parameters were maintained. The fishes were fed with tuna eggs, boiled clam meat, squid, octopus and trash fish thrice in a day. Reproductive behaviour and embryonic development were documented. Spawning took place in between 0900 - 1100 hr and hatched-out occurs, after sunset following an incubation period of 8-9 days. Size of the newly laid egg was 2.0-2.2 mm in length and 1.0-1.2 mm in width. The larval rearing tanks were maintained with UV-treated water and followed the optimal physico-chemical parameters as in the parent tanks. The different light regimes and diets were used for the successful larval rearing. The maximum larval survival (61%) was achieved at the photoperiod of 24 L/0D. Within 15-17 days, the larvae metamorphosed and took up parent colouration and comparatively high growth rate was observed when fed on algae enriched rotifer than those with poly unsaturated fatty acid (PUFA).
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Affiliation(s)
- T T Ajith Kumar
- Centre for Marine Living Resources and Ecology - Field Research Station, Agatti Island - 682 553, Lakshadweep, India.
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Balasubramanian T, Chatterjee TK, Senthilkumar GP, Mani T. Effect of potent ethyl acetate fraction of Stereospermum suaveolens extract in streptozotocin-induced diabetic rats. ScientificWorldJournal 2012; 2012:413196. [PMID: 22593683 PMCID: PMC3349202 DOI: 10.1100/2012/413196] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 12/28/2011] [Indexed: 12/04/2022] Open
Abstract
To evaluate the antihyperglycemic effect of ethyl acetate fraction of ethanol extract of Stereospermum suaveolens in streptozotocin-(STZ-) induced diabetic rats by acute and subacute models. In this paper, various fractions of ethanol extract of Stereospermum suaveolens were prepared and their effects on blood glucose levels in STZ-induced diabetic rats were studied after a single oral administration (200 mg/kg). Administration of the ethyl acetate fraction at 200 mg/kg once daily for 14 days to STZ-induced diabetic rats was also carried out. The parameters such as the fasting blood glucose, hepatic glycogen content, and pancreatic antioxidant levels were monitored. In the acute study, the ethyl acetate fraction is the most potent in reducing the fasting serum glucose levels of the STZ-induced diabetic rats. The 14-day repeated oral administration of the ethyl acetate fraction significantly reduced the fasting blood glucose and pancreatic TBARS level and significantly increased the liver glycogen, pancreatic superoxide dismutase, and catalase activities as well as reduced glutathione levels. The histopathological studies during the subacute treatment have been shown to ameliorate the STZ-induced histological damage of pancreas. This paper concludes that the ethyl acetate fraction from ethanol extract of Stereospermum suaveolens possesses potent antihyperglycemic and antioxidant properties, thereby substantiating the use of plant in the indigenous system of medicine.
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Affiliation(s)
- T Balasubramanian
- Department of Pharmaceutical Chemistry, Bharathi College of Pharmacy, Bharathi Nagara, Mandya, Karnataka-571 422, India
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R. S R, R. Muduli P, Vishnu Vardhan K, Nagarjuna A, Nallathambi T, K. Mishra R, Balasubramanian T. Planktonic Communities and Trophic Interactions in the Kavaratti Waters, Lakshadweep Archipelago, India. ACTA ACUST UNITED AC 2012. [DOI: 10.5923/j.ije.20120202.02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
Wild marine organisms have been used in the discovery and development of traditional and allopathic medical treatments for a long time. Seahorses, a syngnathidae fish, are one of the important candidate organisms which have been used in Chinese traditional medicine from time immemorial. It is believed that seahorses have the potential to cure infertility, baldness, asthma and arthritis. An authentic research work on the biomedical validation of seahorses proved that they have the ability to cure arthritis and its associated inflammation. A Cathepsin-derived peptide from the seahorse species of Hippocampus kuda proved to be effective in chondrocyte cells and its associated impaired arthritis inflammation. Apart from this, seahorses have a putative free radical scavenging effect in controlling the ageing process. More authentic research is needed in order to validate the biomedical potential. This article highlights the role of seahorses' value in traditional medicine and their biomedical properties.
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Affiliation(s)
- K Kumaravel
- Department of Marine Biotechnology, Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai - 608502, Tamil Nadu, India
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Gurudeeban S, Satyavani K, Ramanathan T, Balasubramanian T. Antidiabetic effect of a black mangrove species Aegiceras corniculatum in alloxan-induced diabetic rats. J Adv Pharm Technol Res 2012; 3:52-6. [PMID: 22470894 PMCID: PMC3312728 DOI: 10.4103/2231-4040.93560] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Earlier ethnopharmacological records divulged the traditional usages of mangrove Aegiceras corniculatum (Linn.) Blanco distributed in coastal and estuarine areas of Southeast India. Excluding scientific knowledge of A. corniculatum against diabetes an upgrowing endocrinal disorder, our present study evaluated the effect on alloxan-induced diabetic rats. Diabetes was induced in adult rats of the Wistar strain by intraperitoneal injection of alloxan monohydrate. The experimental rats were administered with leaf suspension of A. corniculatum post orally using an intragastric tube. On completion of the 60-day treatment, a range of biochemical parameters were tested including liver hexokinase, glucose-6phosphatase and fructose 1, 6 bisphosphatase in the liver of control and allaxon-diabetic rats. As a result, A. corniculatum leaf suspension showed moderate reduction in blood glucose (from 382 ± 34 to 105 ± 35), glycosylated hemoglobin, a decrease in the activities of glucose-6 phosphatase and fructose 1, 6-bisphosphatase, and an increase activity of liver hexokinase achieved through the oral administration of extract on 100 mg/kg. The present findings support promising results in terms of antidiabetic activities establishing its candidacy for further purification of individual compound in order to understand their mechanism of action.
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Affiliation(s)
- S. Gurudeeban
- Marine Medicinal Plant Biotechnology Laboratory, Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu, India
| | - K. Satyavani
- Marine Medicinal Plant Biotechnology Laboratory, Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu, India
| | - T. Ramanathan
- Marine Medicinal Plant Biotechnology Laboratory, Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu, India
- Address for correspondence: Dr. T. Ramanathan, Marine Medicinal Plant Biotechnology Laboratory, Centre of Advanced Study in Marine Biology Faculty of Marine Sciences, Annamalai University, Parangipettai 608502, Tamil Nadu, India. E-mail:
| | - T. Balasubramanian
- Marine Medicinal Plant Biotechnology Laboratory, Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu, India
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Annamalai N, Kumar A, Saravanakumar A, Vijaylakshmi S, Balasubramanian T. Characterization of protease from Alcaligens faecalis and its antibacterial activity on fish pathogens. J Environ Biol 2011; 32:781-786. [PMID: 22471216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Alcaligens faecalis AU01 isolated from seafood industry effluent produced an alkaline protease. The optimum culture conditions for growth as well as enzyme production were 37 degrees C and pH 8. The partially purified protease had specific activity of 9.66 with 17.77% recovery with the molecular weight of 33 kDa and it was active between 30-70 degrees C and optimum being at 55 degrees C and pH 9. The enzyme retains more than 85% activity at 70 degrees C and 78% even at pH 10. The enzyme inhibited the growth of fish pathogens such as Flavobacterium sp., Pseudomonas fluorescens, Vibrio harveyi, Proteus sp. and Vibrio parahaemolyticus. From the present study it can be concluded that Alcaligens faecalis AU01 has the potential for aquaculture as probiotic agent and other several applications.
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Affiliation(s)
- N Annamalai
- Faculty of Marine Science, CAS in Marine Biology, Annamalai University, Parangipettai, 608 502, India.
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Gopalakrishnan A, Maran BAV, Puvanendran V, Rajkumar M, Balasubramanian T, Ferguson HW. Neoplasia in the Indian oil sardine, Sardinella longiceps (Valenciennes), and the great barracuda, Sphyraena barracuda (Edwards), from the south-east coast of India. J Fish Dis 2011; 34:881-885. [PMID: 21988360 DOI: 10.1111/j.1365-2761.2011.01299.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- A Gopalakrishnan
- Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai, Tamil Nadu, India
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Jayalakshmi G, Gopalakrishnan N, Panigrahi BK, Balasubramanian T. Grain boundary defects induced room temperature ferromagnetism in V doped ZnO thin films. Cryst Res Technol 2011. [DOI: 10.1002/crat.201100226] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Manivannan K, Karthikai devi G, Anantharaman P, Balasubramanian T. Antimicrobial potential of selected brown seaweeds from Vedalai coastal waters, Gulf of Mannar. Asian Pac J Trop Biomed 2011; 1:114-20. [PMID: 23569739 PMCID: PMC3609169 DOI: 10.1016/s2221-1691(11)60007-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 02/27/2011] [Accepted: 03/16/2011] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVE To evaluate the antimicrobial activity of Turbinaria conoides (T. conoides), Padina gymnospora (P. gymnospora) and Sargassum tenerrimum against human bacterial and fungal pathogens. METHODS The antimicrobial activities of the extracts against various organisms were tested by using disc diffusion method. RESULTS The methanol extract showed the better result than the other extracts. Whereas, the strong antibacterial inhibition was noted in methanol extracts of P. gymnospora against Bacillus subtilus (26.33±1.86) and the mild inhibition of ethanol extracts from T. conoides against Klebsiella pneumoniae (2.33±0.51). Acetone extraction of P. gymnospora had strong antifungal inhibition against Cryptococcus neoformans (23.00±1.78), and acetone extract of T. conoides had mild inhibition against Aspergillus niger (3.00±0.89). CONCLUSIONS The seven different solvent extracts of seaweeds used in the present study have shown significant bacterial action. Further, a detailed study on the principle compound in the seaweeds which is responsible for antimicrobial activity is still needed and it can be achieved by using advanced separation techniques.
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Affiliation(s)
| | | | - P Anantharaman
- Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamilnadu, India
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Annamalai N, Thavasi R, Vijayalakshmi S, Balasubramanian T. Extraction, Purification and Characterization of Thermostable, Alkaline Tolerant α-Amylase from Bacillus cereus. Indian J Microbiol 2011; 51:424-9. [PMID: 23024403 DOI: 10.1007/s12088-011-0160-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 01/21/2011] [Indexed: 10/18/2022] Open
Abstract
Thermostable alkaline α-amylase producing bacterium Bacilluscereus strain isolated from Cuddalore harbour waters grew maximally in both shake flask and fermentor, and produced α-amylase at 35°C, pH 7.5 and 1.0% of substrate concentrations. α-Amylase activity was maximum at 65°C, pH 8.0, 89% of its activity was sustained even at pH 11.0. Added with MnCl(2,) α-amylase activity showed 4% increase but it was inhibited by EDTA. The molecular weight of the purified α-amylase is 42 kDa.
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Affiliation(s)
- N Annamalai
- CAS in Marine Biology, Annamalai University, Parangipettai, 608502 India
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Anand P, Rajakumar D, Jeraud M, Felix AJW, Balasubramanian T. Effects of taurine on glutathione peroxidase, glutathione reductase and reduced glutathione levels in rats. Pak J Biol Sci 2011; 14:219-225. [PMID: 21870645 DOI: 10.3923/pjbs.2011.219.225] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The aim of the present study is to investigate the effects of oral administration of taurine on endogenous glutathione peroxidase (GPx) and Glutathione Reductase (GR) activities and reduced glutathione (GSH) level in normal rats. Normal saline (Group I) or 5% taurine in normal saline was administered in dose of 50 mg (Group II), 250 mg (Group III) or 500 mg kg(-1) of body weight (Group IV) through intragastric intubation for 60 days. GPx and GR enzyme activities and GSH and taurine levels were determined in liver, heart, stomach, kidney and plasma of normal Wistar rats. GPx activity showed an increase in liver, heart, stomach and plasma. GR activity increased in kidney and decreased in liver and plasma. GSH levels increased in liver, stomach and decreased in kidney. Liver showed an increase and heart, stomach and kidney a decrease in taurine level in taurine administered rats when compared to control rats. The results varied from organ to organ and the observed variations among organs might be related to their respective enzymatic, non-enzymatic antioxidant potential and its functions. From the present study it may be concluded that long term oral administration of taurine affects GPx, GR and GSH levels in normal rats.
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Affiliation(s)
- P Anand
- Department of Physiology, Rajah Muthiah Dental College, Annamalai University, Annamalainagar-608 002, Tamilnadu, India
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Silambarasan G, Ramanathan T, Nabeel M, Kalaichelvan V, Kathiresan K, Balasubramanian T. Anti-Inflammatory Activity of the Marine Cyanobacterium Trichodesmium Erythraeum against Carrageenan-Induced Paw Oedema in Wistar Albino Rats. EUR J INFLAMM 2011. [DOI: 10.1177/1721727x1100900108] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Inflammatory diseases, including rheumatic, diseases are a major cause of morbidity of the working force throughout the world. Inflammation is a tissue reaction to infection. The effects are redness (erythema), swelling (oedema) and pain, to the area that can result in loss of function. Cyanobacteria are photosynthetic prokaryotic organisms which are potentially useful in pharmaceuticals, industrial chemicals, and restriction enzymes. Trichodesmium species are non-heterocystous cyanobacteria, commonly found in tropical and subtropical oligotrophic oceans. They occur in filaments of 20–200 cells which often congregate to form larger colonies called blooms that can be seen and often form dense blooms covering vast areas in sub-tropical regions. The present study tested the anti-inflammatory effect of the marine cyanobacterium, Trichodesmium erythraeum in carrageenan-induced inflammation in rats. The aqueous extract showed anti-inflammatory activity at a high dosage (500 mg/kg) and this effect was on par with the commercial drug, indomethacin. The inhibition of inflammation volume was 57.5±5.5 % and 47.5±4.7% respectively, at higher and lower dosages, in 30 minutes of treatment. The control group without any treatment exhibited an increase in the paw volume. This is the first report on the anti-inflammatory effect of marine-derived Trichodesmium erythraeum.
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Affiliation(s)
- G. Silambarasan
- Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu
| | - T. Ramanathan
- Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu
| | - M.A. Nabeel
- Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu
| | - V.K. Kalaichelvan
- Department of Pharmacy, Faculty of Engineering and Technology, Annamalai University, Tamil Nadu, India
| | - K. Kathiresan
- Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu
| | - T. Balasubramanian
- Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamil Nadu
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Thavasi R, Subramanyam Nambaru VRM, Jayalakshmi S, Balasubramanian T, Banat IM. Biosurfactant Production by Pseudomonas aeruginosa from Renewable Resources. Indian J Microbiol 2011; 51:30-6. [PMID: 22282625 PMCID: PMC3209860 DOI: 10.1007/s12088-011-0076-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 05/29/2009] [Indexed: 10/18/2022] Open
Abstract
This study deals with production and characterization of biosurfactant from renewable resources by Pseudomonas aeruginosa. Biosurfactant production was carried out in 3L fermentor using waste motor lubricant oil and peanut oil cake. Maximum biomass (11.6 mg/ml) and biosurfactant production (8.6 mg/ml) occurred with peanut oil cake at 120 and 132 h respectively. Characterization of the biosurfactant revealed that, it is a lipopeptide with chemical composition of protein (50.2%) and lipid (49.8%). The biosurfactant (1 mg/ml) was able to emulsify waste motor lubricant oil, crude oil, peanut oil, kerosene, diesel, xylene, naphthalene and anthracene, comparatively the emulsification activity was higher than the activity found with Triton X-100 (1 mg/ml). Results obtained in the present study showed the possibility of biosurfactant production using renewable, relatively inexpensive and easily available resources. Emulsification activity found with the biosurfactant against different hydrocarbons showed its possible application in bioremediation of environments polluted with various hydrocarbons.
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Affiliation(s)
- R. Thavasi
- Department of Chemical and Biological Sciences, Polytechnic Institute of New York University, 6 Metrotech Center, Brooklyn, NY 11201 USA
| | | | - S. Jayalakshmi
- CAS in Marine Biology, Annamalai University, Parangipettai, Chidambaram, Tamil Nadu 608 502 India
| | - T. Balasubramanian
- CAS in Marine Biology, Annamalai University, Parangipettai, Chidambaram, Tamil Nadu 608 502 India
| | - Ibrahim M. Banat
- School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA Northern Ireland, UK
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Shanthi PMS, Mangalaraja R, Uthirakumar A, Velmathi S, Balasubramanian T, Ashok M. Synthesis and characterization of porous shell-like nano hydroxyapatite using Cetrimide as template. J Colloid Interface Sci 2010; 350:39-43. [DOI: 10.1016/j.jcis.2010.05.046] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 05/13/2010] [Accepted: 05/14/2010] [Indexed: 10/19/2022]
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Karthikeyan R, Somasundaram ST, Manivasagam T, Balasubramanian T, Anantharaman P. Hepatoprotective activity of brown alga Padina boergesenii against CCl4 induced oxidative damage in Wistar rats. ASIAN PAC J TROP MED 2010. [DOI: 10.1016/s1995-7645(10)60168-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Anand P, Rajakumar D, Felix AJW, Balasubramanian T. Effects of oral administration of antioxidant taurine on haematological parameters in Wistar rats. Pak J Biol Sci 2010; 13:785-93. [PMID: 21850928 DOI: 10.3923/pjbs.2010.785.793] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The present study evaluates the effects of oral administration of taurine on haematological parameters in normal wistar rats. Tissue oxidative stress is implicated in pathogenesis of various clinical disorders and antioxidant taurine is emerging as prophylactic and therapeutic agent. However, studies on effects of taurine on normal physiology are not reported in literature. Normal saline (Group I) or 5% taurine in normal saline was administered in dose of 50 mg (Group II), 250 mg (Group III) or 500 mg kg(-1) of b.wt. (Group IV) through intragastric intubation for 60 days. The blood cell counts, haemoglobin content, packed cell volume, blood indices, bleeding time and clotting time were estimated using routine laboratory haematological techniques. Neutrophil's phagocytic activity was determined by nitroblue tetrazolium reduction test; serum lysozyme activity was estimated colorimetrically by the degree to lyse bacterial cell suspension and serum taurine levels were estimated by HPLC fluorimetric technique. Platelet count showed a decrease in Group III and IV when compared with Group I and II (p<0.001). Mean corpuscular haemoglobin of Group III and IV are significantly lowered when compared to Group I (p<0.001). A statistically significant decrease was observed in the mean corpuscular haemoglobin concentration between Group 1 and Group IV (p<0.001). The neutrophil percentage of Group II, Group III and Group IV showed a significant increase over Group I (p<0.001). The percentage of lymphocytes showed a significant decrease in Group II, III and Group IV when compared to Group I (p<0.001). Neutrophil's phagocytic activity is significantly lowered in Group III and IV when compared to Group I (p<0.001). The serum lysozyme activity of Group III and IV showed a significant increase over Group I (at p<0.001). From the present study it may be concluded that long term oral administration of taurine affects normal haematological functions.
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Affiliation(s)
- P Anand
- Department of Physiology, Rajah Muthiah Medical College, Annamalai University, Annamalainagar-608 002, Tamilnadu, India
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