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Brimblecombe KR, Connor-Robson N, Bataille CJR, Roberts BM, Gracie C, O'Connor B, Te Water Naude R, Karthik G, Russell AJ, Wade-Martins R, Cragg SJ. Inhibition of striatal dopamine release by the L-type calcium channel inhibitor isradipine co-varies with risk factors for Parkinson's. Eur J Neurosci 2024; 59:1242-1259. [PMID: 37941514 DOI: 10.1111/ejn.16180] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/25/2023] [Accepted: 10/14/2023] [Indexed: 11/10/2023]
Abstract
Ca2+ entry into nigrostriatal dopamine (DA) neurons and axons via L-type voltage-gated Ca2+ channels (LTCCs) contributes, respectively, to pacemaker activity and DA release and has long been thought to contribute to vulnerability to degeneration in Parkinson's disease. LTCC function is greater in DA axons and neurons from substantia nigra pars compacta than from ventral tegmental area, but this is not explained by channel expression level. We tested the hypothesis that LTCC control of DA release is governed rather by local mechanisms, focussing on candidate biological factors known to operate differently between types of DA neurons and/or be associated with their differing vulnerability to parkinsonism, including biological sex, α-synuclein, DA transporters (DATs) and calbindin-D28k (Calb1). We detected evoked DA release ex vivo in mouse striatal slices using fast-scan cyclic voltammetry and assessed LTCC support of DA release by detecting the inhibition of DA release by the LTCC inhibitors isradipine or CP8. Using genetic knockouts or pharmacological manipulations, we identified that striatal LTCC support of DA release depended on multiple intersecting factors, in a regionally and sexually divergent manner. LTCC function was promoted by factors associated with Parkinsonian risk, including male sex, α-synuclein, DAT and a dorsolateral co-ordinate, but limited by factors associated with protection, that is, female sex, glucocerebrosidase activity, Calb1 and ventromedial co-ordinate. Together, these data show that LTCC function in DA axons and isradipine effect are locally governed and suggest they vary in a manner that in turn might impact on, or reflect, the cellular stress that leads to parkinsonian degeneration.
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Affiliation(s)
- Katherine R Brimblecombe
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
| | - Natalie Connor-Robson
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| | - Carole J R Bataille
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford, UK
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Bradley M Roberts
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| | - Caitlin Gracie
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Bethan O'Connor
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | | | - Gayathri Karthik
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Angela J Russell
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford, UK
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
| | - Stephanie J Cragg
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
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Chrysostomou V, Bell KC, Ng SW, Suresh S, Karthik G, Millet M, Chung Y, Crowston JG. A new model of axon degeneration in the mouse optic nerve using repeat intraocular pressure challenge. Exp Eye Res 2024; 238:109722. [PMID: 37952724 DOI: 10.1016/j.exer.2023.109722] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/29/2023] [Accepted: 11/07/2023] [Indexed: 11/14/2023]
Abstract
We characterize a new experimental model for inducing retinal ganglion cell (RGC) dysfunction and degeneration in mice. C57BL/6J mice were subjected to two acute periods of intraocular pressure (IOP) elevation (50 mmHg for 30 min) by cannulation of the anterior chamber. We used full-field electroretinography and visual evoked potentials (VEPs) to measure subsequent changes in retina and optic nerve function, and histochemical techniques to assess RGC survival and optic nerve structure. In 12 month old mice, a single IOP challenge caused loss and subsequent recovery of RGC function over the following 28 days with minimal cell death and no observed axonal damage. A second identical IOP challenge resulted in persistent RGC dysfunction and significant (36%) loss of RGC somas. This was accompanied by a 16.7% delay in the latency and a 27.6% decrease in the amplitude of the VEP. Severe axonal damage was seen histologically with enlargement of axons, myelin disruption, reduced axon density, and the presence of glial scarring. In contrast, younger 3 month old mice when exposed to a single or repeat IOP challenge showed quicker RGC functional recovery after a single challenge and full functional recovery after a repeat challenge with no detectable optic nerve dysfunction. These data demonstrate a highly reproducible and minimally invasive method for inducing RGC degeneration and axonal damage in mice. Resilience of the optic nerve to damage is highly dependent on animal age. The time-defined nature of functional versus structural loss seen in this model stands to facilitate investigation of neuroglial responses in the retina after IOP injury and the associated evaluation of neuroprotective treatment strategies. Further, the model may be used to investigate the impact of aging and the cellular switch between neurorecovery and neurodegeneration.
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Affiliation(s)
- Vicki Chrysostomou
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore.
| | - Katharina C Bell
- Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore; EYE-ACP, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Save Sight Institute, Charles Perkins Centre, University of Sydney, Australia
| | - Sze Woei Ng
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore
| | - Samyuktha Suresh
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Gayathri Karthik
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Marion Millet
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore
| | - Yingying Chung
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore
| | - Jonathan G Crowston
- Centre for Vision Research, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Singapore Eye Research Institute, The Academia, 20 College Road, 169856, Singapore; Save Sight Institute, Charles Perkins Centre, University of Sydney, Australia
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Sekaran K, Polachirakkal Varghese R, Gnanasambandan R, Karthik G, Ramya I, George Priya Doss C. Molecular modeling of C1-inhibitor as SARS-CoV-2 target identified from the immune signatures of multiple tissues: An integrated bioinformatics study. Cell Biochem Funct 2023; 41:112-127. [PMID: 36517964 DOI: 10.1002/cbf.3769] [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: 08/29/2022] [Revised: 11/02/2022] [Accepted: 11/27/2022] [Indexed: 12/16/2022]
Abstract
The expeditious transmission of the severe acute respiratory coronavirus 2 (SARS-CoV-2), a strain of COVID-19, crumbled the global economic strength and caused a veritable collapse in health infrastructure. The molecular modeling of the novel coronavirus research sounds promising and equips more evidence about the pragmatic therapeutic options. This article proposes a machine-learning framework for identifying potential COVID-19 transcriptomic signatures. The transcriptomics data contains immune-related genes collected from multiple tissues (blood, nasal, and buccal) with accession number: GSE183071. Extensive bioinformatics work was carried out to identify the potential candidate markers, including differential expression analysis, protein interactions, gene ontology, and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment studies. The overlapping investigation found SERPING1, the gene that encodes a glycosylated plasma protein C1-INH, in all three datasets. Furthermore, the immuno-informatics study was conducted on the C1-INH protein. 5DU3, the protein identifier of C1-INH, was fetched to identify the antigenicity, major histocompatibility (MHC) Class I and II binding epitopes, allergenicity, toxicity, and immunogenicity. The screening of peptides satisfying the vaccine-design criteria based on the metrics mentioned above is performed. The drug-gene interaction study reported that Rhucin is strongly associated with SERPING1. HSIC-Lasso (Hilbert-Schmidt independence criterion-least absolute shrinkage and selection operator), a model-free biomarker selection technique, was employed to identify the genes having a nonlinear relationship with the target class. The gene subset is trained with supervised machine learning models by a leave-one-out cross-validation method. Explainable artificial intelligence techniques perform the model interpretation analysis.
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Affiliation(s)
- Karthik Sekaran
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India
| | | | - R Gnanasambandan
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India
| | - G Karthik
- Department of Medicine, Christian Medical College, Vellore, India
| | - I Ramya
- Department of Medicine, Christian Medical College, Vellore, India
| | - C George Priya Doss
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India
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Venkateswara Rao B, Pavan Kumar P, Ramalingam V, Karthik G, Andugulapati SB, Suresh Babu K. Piperazine tethered bergenin heterocyclic hybrids: design, synthesis, anticancer activity, and molecular docking studies. RSC Med Chem 2022; 13:978-985. [PMID: 36092140 PMCID: PMC9383709 DOI: 10.1039/d2md00116k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/25/2022] [Indexed: 09/29/2023] Open
Abstract
In an attempt to develop natural product-based anticancer agents, a series of novel piperazine-linked bergenin heterocyclic hybrids bearing arylthiazolyl (5a-e), benzothiazolyl (10a-i), and arylsulfonyl (13a-o) were synthesized using the classical Mannich reaction and evaluated for their anticancer activity. All the synthesized derivatives were assessed for in vitro cytotoxic activity against a panel of human cancer and normal cell lines and the results showed that most of the compounds exhibited significant cytotoxic activity against cancer cells and mild cytotoxicity against normal cells. In particular, the compounds 5a, 5c, 10f, and 13o showed potent cytotoxic activity against tongue and oral cancer cell lines compared to the parent compound (<100 μM). Considering the efficacy, the compounds 5a, 5c, 10f, and 13o were subjected to cell cycle analysis and the results indicated that the compounds mitigated the cell cycle progression at the G0/G1 phase in the tongue and oral cancer cell lines. Subsequently, the annexin V/PI staining assay demonstrated that the compounds 5a, 5c, 10f, and 13o induced early and late apoptosis against tongue cancer and necrosis against oral cancer. Further, gene expression analysis revealed that 5a, 5c, and 13o treatment regulated the BAX and BcL-2 expression and also the selected compounds significantly reduced the expression level of vimentin, oct-4, and nanog. In addition, molecular docking studies revealed that the selected derivatives have strong binding energy with the BcL2 protein and downregulates the expression. Taken together, the study results implied that these compounds are promising anticancer candidates by modulating the epithelial to mesenchymal transition axis and could be considered for further development of novel anticancer drugs.
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Affiliation(s)
- Banoth Venkateswara Rao
- Centre for Natural Products & Traditional Knowledge, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad - 201002 India
| | - P Pavan Kumar
- Centre for Natural Products & Traditional Knowledge, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
| | - Vaikundamoorthy Ramalingam
- Centre for Natural Products & Traditional Knowledge, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad - 201002 India
| | - G Karthik
- Applied Biology, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
| | - Sai Balaji Andugulapati
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad - 201002 India
- Applied Biology, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
| | - K Suresh Babu
- Centre for Natural Products & Traditional Knowledge, CSIR-Indian Institute of Chemical Technology Hyderabad 500 007 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad - 201002 India
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Vijayalakshmi P, Muthumanickam K, Karthik G, Sakthivel S. Diagnosis of infertility from adenomyosis and endometriosis through entroxon based intelligent water drop back propagation neural networks. IFS 2022. [DOI: 10.3233/jifs-212866] [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] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Adenomyosis is an abnormality in the uterine wall of women that adversely affects their normal life style. If not treated properly, it may lead to severe health issues. The symptoms of adenomyosis are identified from MRI images. It is a gynaecological disease that may lead to infertility. The presence of red dots in the uterus is the major symptom of adenomyosis. The difference in the extent of these red dots extracted from MRI images shows how significant the deviation from normality is. Thus, we proposed an entroxon-based bio-inspired intelligent water drop back-propagation neural network (BIWDNN) model to discover the probability of infertility being caused by adenomyosis and endometriosis. First, vital features from the images are extracted and segmented, and then they are classified using the fuzzy C-means clustering algorithm. The extracted features are then attributed and compared with a normal person’s extracted attributes. The proposed BIWDNN model is evaluated using training and testing datasets and the predictions are estimated using the testing dataset. The proposed model produces an improved diagnostic precision rate on infertility.
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Affiliation(s)
- P. Vijayalakshmi
- Department of Computer Science and Engineering, Knowledge Institute of Technology, Salem, Tamilnadu, India
| | - K. Muthumanickam
- Department of Information Technology, Kongunadu College of and Engineering and Technology, Thollupatti, Tiruchirappali, Tamilnadu, India
| | - G. Karthik
- Department of Information Technology, Kongunadu College of and Engineering and Technology, Thollupatti, Tiruchirappali, Tamilnadu, India
| | - S. Sakthivel
- Department of Computer Science and Engineering, Arulmigu Arthanareeswarar, Tiruchengode, Tamilnadu, India
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Karthik G, Plass J, Beltz AM, Liu Z, Grabowecky M, Suzuki S, Stacey WC, Wasade VS, Towle VL, Tao JX, Wu S, Issa NP, Brang D. Visual speech differentially modulates beta, theta, and high gamma bands in auditory cortex. Eur J Neurosci 2021; 54:7301-7317. [PMID: 34587350 DOI: 10.1111/ejn.15482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 06/01/2021] [Revised: 08/20/2021] [Accepted: 08/28/2021] [Indexed: 12/13/2022]
Abstract
Speech perception is a central component of social communication. Although principally an auditory process, accurate speech perception in everyday settings is supported by meaningful information extracted from visual cues. Visual speech modulates activity in cortical areas subserving auditory speech perception including the superior temporal gyrus (STG). However, it is unknown whether visual modulation of auditory processing is a unitary phenomenon or, rather, consists of multiple functionally distinct processes. To explore this question, we examined neural responses to audiovisual speech measured from intracranially implanted electrodes in 21 patients with epilepsy. We found that visual speech modulated auditory processes in the STG in multiple ways, eliciting temporally and spatially distinct patterns of activity that differed across frequency bands. In the theta band, visual speech suppressed the auditory response from before auditory speech onset to after auditory speech onset (-93 to 500 ms) most strongly in the posterior STG. In the beta band, suppression was seen in the anterior STG from -311 to -195 ms before auditory speech onset and in the middle STG from -195 to 235 ms after speech onset. In high gamma, visual speech enhanced the auditory response from -45 to 24 ms only in the posterior STG. We interpret the visual-induced changes prior to speech onset as reflecting crossmodal prediction of speech signals. In contrast, modulations after sound onset may reflect a decrease in sustained feedforward auditory activity. These results are consistent with models that posit multiple distinct mechanisms supporting audiovisual speech perception.
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Affiliation(s)
- G Karthik
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - John Plass
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Adriene M Beltz
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Zhongming Liu
- Department of Biomedical Engineering and Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan, USA
| | - Marcia Grabowecky
- Department of Psychology, Northwestern University, Evanston, Illinois, USA
| | - Satoru Suzuki
- Department of Psychology, Northwestern University, Evanston, Illinois, USA
| | - William C Stacey
- Department of Neurology and Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Vibhangini S Wasade
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA.,Department of Neurology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Vernon L Towle
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - James X Tao
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - Shasha Wu
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - Naoum P Issa
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - David Brang
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
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Kumarguru BN, Karthik G, Kumar MU, Prashanth R, Janakiraman P. Utility of Lemon Solution Rehydration Technique for Processing Haemorrhagic Cytology Samples: A Comparative Study using Different Techniques. J Clin Diagn Res 2020. [DOI: 10.7860/jcdr/2020/43218.13563] [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: 11/24/2022]
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Varghese R, Neeravi A, Subramanian N, Pavithra B, Kavipriya A, Kumar JL, Girish Kumar CP, Jeyraman Y, Karthik G, Verghese VP, Veeraraghavan B. Clonal similarities and sequence-type diversity of invasive and carriage Streptococcus pneumoniae in India among children under 5 Years. Indian J Med Microbiol 2019; 37:358-362. [PMID: 32003333 DOI: 10.4103/ijmm.ijmm_19_348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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] [Indexed: 11/04/2022]
Abstract
Background Pneumococcal pneumonia is one of the major causes of mortality in children less than 5 years in Asia, especially in India. Available PCVs have less serotype coverage in India compared to western countries. Moreover, the baseline pneumococcal serotype and sequence type data is limited and available data doesn't represent the entire India. With this background we aimed to characterize invasive and carriage isolates of S. pneumoniae from a tertiary care hospital in South India. Materials and Methods A total of 221 S. pneumoniae isolates, invasive (n=138) and carriage (n=83) between the time period of 2012-2018 were included. Isolates was identified and confirmed using standard laboratory protocols. Serotyping was performed by Customized sequential multiplex PCR and MLST as described in www.pubmlst.org. Results The major serotypes were 19F, 6B, 14, 6A and 19A and the sequence types (ST) were ST63, 236 and 230. Predominant STs in invasive was ST 63 whereas in carriage were ST4894 and 1701. High level ST diversity in carriage was observed. Majority of the STs were SLVs or DLVs of previously reported STs or PMEN clones. Phylogenetic analyses of the STs revealed gradual expansion of three PMEN CCs CC320, 63 and 230. Conclusion The vaccine serotypes were the predominant ones found to be associated with IPD, PMEN clones, new STs and antimicrobial resistance. Accordingly, PCV13 is expected to provide invasive serotype coverage of 75% in Indian children less than 5 years. This study provides baseline serotype and sequence type data prior to the introduction of PCV in South India.
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Affiliation(s)
- Rosemol Varghese
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Ayyanraj Neeravi
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Nithya Subramanian
- Department of Paediatrics, Christian Medical College, Chennai, Tamil Nadu, India
| | - B Pavithra
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - A Kavipriya
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Jones Lionel Kumar
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - C P Girish Kumar
- ICMR, National Institute of Epidemiology, Chennai, Tamil Nadu, India
| | - Yuvraj Jeyraman
- ICMR, National Institute of Epidemiology, Chennai, Tamil Nadu, India
| | - G Karthik
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Valsan P Verghese
- Department of Paediatrics, Christian Medical College, Chennai, Tamil Nadu, India
| | - Balaji Veeraraghavan
- Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
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Shaheer ARM, Karthik P, Karthik G, Shankar MV, Neppolian B. Dual role of a g-C3N4/carbon intra-Schottky junction in charge carrier generation and separation for efficient solar H2 production. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00757a] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Intra-Schottky junction facilitated charge carrier generation and separation in g-C3N4 for efficient solar H2 production.
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Affiliation(s)
- A. R. Mahammed Shaheer
- SRM Research Institute
- SRM Institute of Science and Technology
- Chennai – 603203
- India
- Department of Physics and Nanotechnology
| | - P. Karthik
- SRM Research Institute
- SRM Institute of Science and Technology
- Chennai – 603203
- India
- Department of Chemistry
| | - G. Karthik
- Department of Nuclear Physics
- University of Madras
- Chennai – 600024
- India
| | - M. V. Shankar
- Nanocatalysis and Solar Fuels Research Laboratory
- Department of Materials Science and Nanotechnology
- Yogi Vemana University
- Kadapa – 516005
- India
| | - B. Neppolian
- SRM Research Institute
- SRM Institute of Science and Technology
- Chennai – 603203
- India
- Department of Chemistry
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Kulkarni V, Poonam D, Karthik G, Nataraj B, Shylaja D, Ramesh B. Evaluation of session on professionalism in undergraduate, intern and postgraduate orientation workshop. J ANAT SOC INDIA 2018. [DOI: 10.1016/j.jasi.2018.06.232] [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: 10/28/2022]
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11
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Razak A, Nagesh KN, Karthik G, Pillai MS, Mohanty PK. Morbidities in Neonates Delivered Electively at Early Term. J Obstet Gynaecol India 2016; 66:248-51. [PMID: 27382218 PMCID: PMC4912492 DOI: 10.1007/s13224-015-0739-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 06/10/2015] [Accepted: 07/01/2015] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE To study the incidence of elective cesarean deliveries at term and to correlate their neonatal outcomes at different gestational ages (37(0/7)-40(6/7)). METHODS Outcomes including the rate of NICU admissions, usage of ventilator/CPAP, and other morbidities were analysed and compared with the gestational age during the study period from January 2012 to April 2013. RESULTS The incidences of elective deliveries at 37, 38, 39, and 40 weeks of gestation were 10.6, 29.7, 28, and 31.5 %, respectively. NICU admissions-RR 3.94 (95 % CI 1.92-8.09), respiratory distress-RR 5.255 (95 % CI 1.9-14.4), ventilatory usage, and hospitalization stay (P value < 0.05) were higher in neonates born at 37(0/7-6/7) versus 39(0/7-6/7) weeks (least morbidity group). CONCLUSION Despite recommendations, more than one-third of term babies are delivered electively at <39 weeks. The fivefold augmented respiratory morbidity and fourfold increased NICU admissions in early term neonates, and the least morbidity in neonates delivered at 39 weeks emphasize the importance of restricting the non-emergent/elective deliveries to 39 weeks of gestation.
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Affiliation(s)
- Abdul Razak
- />Department of Neonatology, Manipal Hospital, Bangalore, India
| | - Karthik N. Nagesh
- />Department of Neonatology, Manipal Hospital, Bangalore, India
- />Manipal Group of Hospitals, Bangalore, India
| | - Gayathri Karthik
- />Department of Obstetrics and Gynaecology, Manipal Hospital, Bangalore, India
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Reddy BS, Veerabhadra Reddy V, Karthik G, Jagadeesh B. Sequential glycosylation/endo-dig cyclization of sugar enynones for the synthesis of pyrano[3,2-c]furan scaffolds. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.02.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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13
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Karthik G, Sundaravadivelu M, Rajkumar P, Manikandan M. Diaza-adamantane derivatives as corrosion inhibitor for copper in nitric acid medium. Res Chem Intermed 2014. [DOI: 10.1007/s11164-014-1846-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Rajasekaran T, Karthik G, Sridhar B, Subba Reddy BV. Dual Behavior of Isatin-Based Cyclic Ketimines with Dicarbomethoxy Carbene: Expedient Synthesis of Highly Functionalized Spirooxindolyl Oxazolidines and Pyrrolines. Org Lett 2013; 15:1512-5. [DOI: 10.1021/ol400287q] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- T. Rajasekaran
- Natural Product Chemistry, Laboratory of X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - G. Karthik
- Natural Product Chemistry, Laboratory of X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - B. Sridhar
- Natural Product Chemistry, Laboratory of X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - B. V. Subba Reddy
- Natural Product Chemistry, Laboratory of X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
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Ramakrishna K, Peter J, Karthik G, Abraham A, Surekha V, Karthik R, Chacko B. Influenza A (H1N1) 2009 pandemic: was there a difference in the two waves in patients requiring admission to the intensive-care unit? Clin Microbiol Infect 2011; 17:1355-8. [DOI: 10.1111/j.1469-0691.2011.03584.x] [Citation(s) in RCA: 9] [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: 11/29/2022]
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Ravikumar L, Kalaivani SS, Murugesan A, Vidhyadevi T, Karthik G, Kirupha SD, Sivanesan S. Synthesis, characterization, and heavy metal ion adsorption studies of polyamides, polythioamides having pendent chlorobenzylidine rings. J Appl Polym Sci 2011. [DOI: 10.1002/app.33968] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nambiar SR, Prathish KP, Karthik G, Rao TP. Hybrid gold atomic cluster–cobalt oxide scaffolds for dual tandem electrocatalytic sensing of cysteine. Biosens Bioelectron 2011; 26:3920-6. [DOI: 10.1016/j.bios.2011.03.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/10/2011] [Accepted: 03/11/2011] [Indexed: 11/29/2022]
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Kulangiappar K, Karthik G, Kulandainathan MA. Electrochemical Method for the Preparation of Dibromomethyl, Bis(bromomethyl), and Bis(dibromomethyl) Arenes. SYNTHETIC COMMUN 2009. [DOI: 10.1080/00397910802654757] [Citation(s) in RCA: 7] [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: 10/20/2022]
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Sharma A, Bakhshi S, Raina V, Thulkar S, Sharma DN, Karthik G, Kumar L. ABVD versus EVAP as first line therapy for Hodgkin’s Lymphoma: Result from a phase III trial. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.8533] [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: 11/20/2022] Open
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Karthik G, Kulangiappar K, Marken F, Kulandainathan MA. Electrochemically promoted Friedel–Crafts acylation of aromatic compounds. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.02.084] [Citation(s) in RCA: 3] [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: 11/29/2022]
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Abstract
Intraductal papillary neoplasms (IPNs) of breast form a wide spectrum of pathological changes with benign intraductal papilloma occupying one end of the spectrum and papillary carcinoma at the other end. Intraductal papillomas are known to occur anywhere within the ductal system and are broadly classified into central and peripheral types. Intraductal papillary carcinoma is an uncommon ductal malignancy forming papillary structures, and these lesions characteristically lack the myoepithelial layer present in benign papillary neoplasms. Three basic patterns of IPNs are recognized on ultrasound - intraductal mass with or without ductal dilatation, intracystic mass and a predominantly solid pattern with the intraductal mass totally filling the duct. Benign papillomas are known to exhibit calcifications which tend to be extremely dense and coarse. IPNs are highly vascular tumours and have a propensity to bleed spontaneously. A distinct vascular pedicle is identified within the central core of IPNs, with branching vessels arborising within the mass. In an older age group, presence of a large solid component and evidence of spontaneous intracystic bleed are more suggestive of papillary carcinomas than benign papillomas. We have serially studied 42 cases of intraductal papillary neoplasms with sonomammography and mammography from 2001 to 2004.
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Affiliation(s)
- S Ganesan
- Department of Radiology and Imaging, G.K.N.M Hospital and Research Centre, PN Palayam, Coimbatore-641037, India
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Karthik G, Kumar A. Environment-induced corrections to the spin Hamiltonian as dynamic frequency shifts in nuclear magnetic resonance. J Chem Phys 2000. [DOI: 10.1063/1.1313526] [Citation(s) in RCA: 2] [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: 11/14/2022] Open
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