516 results on '"Sreekumaran Nair"'
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2. Predictive models for fentanyl dose requirement and postoperative pain using clinical and genetic factors in patients undergoing major breast surgery
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Shathish Kumar, Ramasamy Kesavan, Sarath Chandra Sistla, Prasanth Penumadu, Harivenkatesh Natarajan, Uppugunduri S. Chakradhara Rao, Sreekumaran Nair, Venkatesan Vasuki, and Pankaj Kundra
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Anesthesiology and Pain Medicine ,Neurology ,Neurology (clinical) - Published
- 2022
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3. Maternal and perinatal outcome in pregnancies complicated with portal hypertension: a systematic review and meta-analysis
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Koustav Pal, Deepthy Melepurakkal Sadanandan, Avantika Gupta, Deepthi Nayak, Manita Pyakurel, Arun Keepanasseril, Dilip Kumar Maurya, N. Sreekumaran Nair, and Anish Keepanasseril
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Hepatology - Abstract
Portal hypertension is secondary to either cirrhotic or non-cirrhotic causes, and complicating pregnancy poses a challenge to the treating team. A systematic review was performed to determine maternal and perinatal outcomes in women with portal hypertension. Outcomes were compared among those with cirrhotic (CPH) with non-cirrhotic portal hypertension (NCPH) as well as non-cirrhotic portal fibrosis (NCPF) with extra-hepatic portal vein obstruction (EHPVO).Medline and EMBASE databases were searched for studies reporting outcomes among pregnant women with portal hypertension. Reference lists from relevant papers and reviews were hand-searched for appropriate citations. Data were extracted to describe maternal complications, obstetric and neonatal outcomes. A random-effects model was used to derive pooled estimates of various outcomes, and final estimates were reported as percentages with a 95% confidence interval (CI). Cumulative, sequential and sensitivity analysis was studied to assess the temporal trends of outcomes over the period.Information on 895 pregnancies among 581 patients with portal hypertension was included from 26 studies. Portal hypertension was diagnosed during pregnancy in 10% (95% CI 4-24%). There were 22 maternal deaths (0%, 95% CI 0-1%), mostly following complications from variceal bleeding or hepatic decompensation. Variceal bleeding complicated in 14% (95% CI 9-20%), and endoscopic interventions were performed in 12% (95% CI 8-17%) during pregnancy. Decompensation of liver function occurred in 7% (95% CI 3-12%). Thrombocytopenia was the most common complication (41%, 95% CI 23-60%). Miscarriages occurred in 14% (95% CI 8-20%), preterm birth in 27% (95% CI 19-37%), and low birth weights in 22% (95% CI 15-30%). Risk of postpartum hemorrhage was higher (RR 5.09, 95% CI 1.84-14.12), and variceal bleeding was lower (RR 0.51, 95% CI 0.30-0.86) among those with CPH compared to NCPH. Risk of various outcomes was comparable between NCPF and EHPVO.One in ten pregnancies complicated with portal hypertension is diagnosed during pregnancy, and thrombocytopenia is the most common complication. Hepatic decompensation and variceal bleeding remain the most common cause of maternal deaths, with reduced rates of bleeding and its complications reported following the introduction of endoscopic procedures during pregnancy. CPH increases the risk of postpartum hemorrhage, whereas variceal bleeding is higher among NCPH.
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- 2022
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4. Interventions for dialysis patients with hepatitis C virus (HCV) infection
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Attur Ravindra Prabhu, Indu Ramachandra Rao, Shankar Prasad Nagaraju, Eti Rajwar, Bhumika T Venkatesh, Sreekumaran Nair N, Ganesh Pai, Nageswara P Reddy, and Deepak Suvarna
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Pharmacology (medical) - Published
- 2023
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5. A novel study on a centrifugal humidifier for building cooling
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Sampath Suranjan Salins, Shiva Kumar, S.V. Kota Reddy, and Prasanth Sreekumaran Nair
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Fluid Flow and Transfer Processes ,General Energy ,Fuel Technology ,Renewable Energy, Sustainability and the Environment ,Process Chemistry and Technology - Published
- 2022
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6. Role of altered IL‐33/ST2 immune axis in the immunobiology of Guillain‐Barré syndrome
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Praveen P. Sharma, Doniparthi V. Seshagiri, Madhu Nagappa, Thrinath Mullapudi, Nikhitha Sreenivas, Saikat Dey, Sumanth Shivaram, Rahul Wahatule, Vijay Kumawat, Binu V. Sreekumaran Nair, Sriganesh Kamath, Sanjib Sinha, Arun B. Taly, and Monojit Debnath
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Genotype ,Neurology ,Humans ,Neurology (clinical) ,Guillain-Barre Syndrome ,Interleukin-33 ,Interleukin-1 Receptor-Like 1 Protein ,Polymorphism, Single Nucleotide - Abstract
The IL-33/ST2 immune axis plays crucial roles in infection and immunity. A dysregulated IL-33/ST2 axis can induce autoimmune reaction and inflammatory responses. Guillain-Barré syndrome (GBS) is an acute peripheral neuropathy, mostly caused by post-infection autoimmunity. The role of IL-33/ST2 axis is not known in GBS. This study aimed to explore the role of IL-33/ST2 axis in GBS.Three single nucleotide polymorphisms (SNPs) of Il33 gene (rs16924159, rs7044343, rs1342336) and three SNPs of Il1rl1 gene (rs10192157, rs1041973, rs10206753) coding for suppressor of tumorigenicity 2 (ST2) were genotyped in 179 GBS patients and 186 healthy controls by TaqMan Allelic Discrimination Assay. Plasma levels of IL-33 and sST2 were measured in a subset of GBS patients (n = 80) and healthy controls (n = 80) by ELISA.The frequencies of CC genotype of rs10192157 (p = 0.043) and TT genotype of rs10206753 (p = 0.036) SNPs of Il1rl1 gene differed significantly between GBS patients and healthy controls. Gene-gene interaction between Il33 and Il1rl1 genes also conferred significant risk for GBS. In addition, the plasma sST2 levels were significantly elevated in GBS patients compared to healthy subjects (24,934.31 ± 1.81 pg/ml vs. 12,518.97 ± 1.51 pg/ml, p 0.001). Plasma sST2 levels showed a significant correlation with the disability scores at the peak of neurological deficit in GBS patients.The IL-33/ST2 axis is suggested to influence the immunopathogenesis of GBS. Genetic variants of Il1rl1 gene might serve as a risk determinant of GBS and plasma sST2 levels might emerge as a biomarker of severity of GBS, if replicated further by other studies.
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- 2022
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7. Variations within Toll‐like receptor ( <scp>TLR</scp> ) and <scp>TLR</scp> signaling pathway‐related genes and their synergistic effects on the risk of <scp>Guillain‐Barré</scp> syndrome
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Debprasad Dutta, Madhu Nagappa, Binu V. Sreekumaran Nair, Sumit Kumar Das, Rahul Wahatule, Sanjib Sinha, Ravi Vasanthapuram, Arun B. Taly, and Monojit Debnath
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General Neuroscience ,Neurology (clinical) - Published
- 2022
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8. An Auxiliary Approach to Prediction of Binary Outcome with Bayesian Network Model: Exploration with Data for Recurrence of Breast Cancer
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Sachit Ganapathy, KT Harichandrakumar, Kadhiravan Tamilarasu, Prasanth Penumadu, and N Sreekumaran Nair
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Clinical Biochemistry ,General Medicine - Abstract
Introduction: Logistic regression is the classical statistical model that is incorporated to predict a binary outcome variable. These models have theoretical assumptions of independence of predictor variables and linearity of association with the outcome in the logarithmic scale. Alternative models developed in the machine learning context like Naïve Bayes model with similar assumptions and Bayesian Network (BN) model can be used for binary prediction. Aim: To compare the predictive performance of logistic regression, Naïve Bayes and BN model in predicting the recurrence of Breast cancer. Materials and Methods: The dataset was procured from UCI Machine Learning repository on recurrence of breast cancer. The study was done on retrospective data from December 2021 to July 2022. The sample size was boosted with the bootstrapping with logistic regression model. The dataset was split into training (70%) and testing (30%) dataset for internal validation. The effect estimates of the potential prognostic variables were estimated using multiple logistic regression model. Naïve Bayes and BN model was also learnt from the training dataset. The indices of predictive accuracy were estimated for the models in both training and testing dataset. Results: Degree of malignancy and side of affected breast were found to be significant predictors of recurrence of breast cancer. BN model had the least misclassification rate and the best sensitivity in comparison to other models in spite of imbalance in outcome variable. Conclusion: BN model performed the best in comparison to logistic regression model when the assumptions of logistic regression model were violated and there is imbalance in proportion of outcome.
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- 2023
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9. Psychological factors influencing patent filing among faculty in Higher Educational Institutions in India
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Shyam Sreekumaran Nair and Santhi Perumal
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Strategy and Management ,Management Science and Operations Research - Published
- 2021
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10. Diet Effects on Cerebrospinal Fluid Amino Acids Levels in Adults with Normal Cognition and Mild Cognitive Impairment
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Kate J. Russin, Suzanne Craft, K. Sreekumaran Nair, Laura D. Baker, and Thomas J. Montine
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Male ,medicine.medical_specialty ,Arginine ,Saturated fat ,Disease ,Spinal Puncture ,cerebrospinal fluid ,Eating ,Cerebrospinal fluid ,mild cognitive impairment ,Cognition ,Valine ,Internal medicine ,Medicine ,Humans ,Cognitive Dysfunction ,Aged ,chemistry.chemical_classification ,amino acids ,diet intervention ,business.industry ,General Neuroscience ,General Medicine ,Amino acid ,Diet ,Psychiatry and Mental health ,Clinical Psychology ,Glycemic index ,Endocrinology ,chemistry ,Female ,Geriatrics and Gerontology ,Isoleucine ,business ,Alzheimer’s disease ,Biomarkers ,Research Article - Abstract
Background: Exploration of cerebrospinal fluid (CSF) amino acids and the impact of dietary intake on central levels may provide a comprehensive understanding of the metabolic component of Alzheimer’s disease. Objective: The objective of this exploratory study was to investigate the effects of two diets with varied nutrient compositions on change in CSF amino acids levels in adults with mild cognitive impairment (MCI) and normal cognition (NC). Secondary objectives were to assess the correlations between the change in CSF amino acids and change in Alzheimer’s disease biomarkers. Methods: In a randomized, parallel, controlled feeding trial, adults (NC, n = 20; MCI, n = 29) consumed a high saturated fat (SFA)/glycemic index (GI) diet [HIGH] or a low SFA/GI diet [LOW] for 4 weeks. Lumbar punctures were performed at baseline and 4 weeks. Results: CSF valine increased and arginine decreased after the HIGH compared to the LOW diet in MCI (ps = 0.03 and 0.04). This pattern was more prominent in MCI versus NC (diet by diagnosis interaction ps = 0.05 and 0.09), as was an increase in isoleucine after the HIGH diet (p = 0.05). Changes in CSF amino acids were correlated with changes in Alzheimer’s disease CSF biomarkers Aβ42, total tau, and p-Tau 181, with distinct patterns in the relationships by diet intervention and cognitive status. Conclusion: Dietary intake affects CSF amino acid levels and the response to diet is differentially affected by cognitive status.
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- 2021
11. Factors Associated With Neonatal Pneumonia and its Mortality in India: A Systematic Review and Meta-Analysis
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N. Sreekumaran Nair, Leslie Edward Lewis, Vijay Shree Dhyani, Shruti Murthy, Myron Godinho, Theophilus Lakiang, and Bhumika T. Venkatesh
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PROSPERO 2016 CRD42016044019 (risk factors) ,Infant, Newborn ,Alveolar-arterial oxygen gradient ,Infant ,Pneumonia, Ventilator-Associated ,Infant, Premature, Diseases ,Respiratory distress ,Infant, Low Birth Weight ,Respiration, Artificial ,Risk factors ,PROSPERO 2016 CRD42016045398 (mortality) ,Pregnancy ,Infant Mortality ,Pediatrics, Perinatology and Child Health ,Humans ,Ventilator-associated pneumonia ,Female ,Systematic Review - Abstract
Background Neonatal pneumonia remains a significant contributor to infant mortality in India and responsible for increased prevalence of infant deaths globally. Objective To identify risk factors associated with neonatal pneumonia and its mortality in India. Study design A systematic review was conducted including both analytic study designs and descriptive study designs, which reported a quantitative analysis of factors associated with all the three types of pneumonia among neonates. The search was conducted from August to December, 2016 on the following databases; CINAHL, EMBASE, Ovid MEDLINE, PubMed, ProQuest, SCOPUS, Web of Science, WHO IMSEAR and IndMED. The search was restricted to Indian setting. Participants The population of interest was neonates. Outcomes The outcome measures included risk factors for incidences and mortality predictors of neonatal pneumonia. These could be related to neonate, maternal and pregnancy, caregiver, family, environment, healthcare system, iatrogenic and others. Results A total of three studies were included. For risk factors, two studies on ventilator-associated pneumonia were included with 194 neonates; whereas for mortality predictors, only one study with 150 neonates diagnosed with pneumonia was included. 11 risk factors were identified from two studies: duration of mechanical ventilation, postnatal age, birth weight, prematurity, sex of the neonate, length of stay in NICU, primary diagnosis, gestational age, number of re-intubation, birth asphyxia, and use of nasogastric tube. Metaanalysis with random-effects model was possible only for prematurity (250 mm Hg was found to be the single most significant predictor of mortality due to pneumonia in neonates. Conclusion The study found scant evidence from India on risk factors of neonatal pneumonia other than ventilator-associated pneumonia. Electronic Supplementary Material Supplementary material is available in the online version of this article at 10.1007/s13312-021-2374-4
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- 2021
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12. Impaired Muscle Mitochondrial Function in Familial Partial Lipodystrophy
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Vinaya Simha, John D. Port, Claudio Cobelli, Ivan Vuckovic, Katherine A. Klaus, Ian R. Lanza, Nathan Le Brasseur, Surendra Dasari, K. Sreekumaran Nair, and Marcello C. Laurenti
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Adult ,Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Biology ,Mitochondrion ,Biochemistry ,Muscle hypertrophy ,Young Adult ,Absorptiometry, Photon ,Endocrinology ,Insulin resistance ,Internal medicine ,medicine ,Humans ,Muscle Strength ,Muscle, Skeletal ,Clinical Research Articles ,Aged ,Catabolism ,Gene Expression Profiling ,Biochemistry (medical) ,Skeletal muscle ,Middle Aged ,medicine.disease ,Familial partial lipodystrophy ,Lipodystrophy, Familial Partial ,Mitochondria, Muscle ,medicine.anatomical_structure ,Mitochondrial biogenesis ,Proteolysis ,Physical Endurance ,Female ,Lipodystrophy - Abstract
Context Familial partial lipodystrophy (FPL), Dunnigan variety is characterized by skeletal muscle hypertrophy and insulin resistance besides fat loss from the extremities. The cause for the muscle hypertrophy and its functional consequences is not known. Objective To compare muscle strength and endurance, besides muscle protein synthesis rate between subjects with FPL and matched controls (n = 6 in each group). In addition, we studied skeletal muscle mitochondrial function and gene expression pattern to help understand the mechanisms for the observed differences. Methods Body composition by dual-energy X-ray absorptiometry, insulin sensitivity by minimal modelling, assessment of peak muscle strength and fatigue, skeletal muscle biopsy and calculation of muscle protein synthesis rate, mitochondrial respirometry, skeletal muscle transcriptome, proteome, and gene set enrichment analysis. Results Despite increased muscularity, FPL subjects did not demonstrate increased muscle strength but had earlier fatigue on chest press exercise. Decreased mitochondrial state 3 respiration in the presence of fatty acid substrate was noted, concurrent to elevated muscle lactate and decreased long-chain acylcarnitine. Based on gene transcriptome, there was significant downregulation of many critical metabolic pathways involved in mitochondrial biogenesis and function. Moreover, the overall pattern of gene expression was indicative of accelerated aging in FPL subjects. A lower muscle protein synthesis and downregulation of gene transcripts involved in muscle protein catabolism was observed. Conclusion Increased muscularity in FPL is not due to increased muscle protein synthesis and is likely due to reduced muscle protein degradation. Impaired mitochondrial function and altered gene expression likely explain the metabolic abnormalities and skeletal muscle dysfunction in FPL subjects.
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- 2021
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13. Impact of Genetic Variants on Postoperative Pain and Fentanyl Dose Requirement in Patients Undergoing Major Breast Surgery: A Candidate Gene Association Study
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Shathish Kumar, Ramasamy Kesavan, Sarath Chandra Sistla, Prasanth Penumadu, Harivenkatesh Natarajan, Sreekumaran Nair, Uppugunduri S. Chakradhara Rao, Vasuki Venkatesan, and Pankaj Kundra
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Anesthesiology and Pain Medicine - Abstract
Postoperative analgesia is crucial for the early and effective recovery of patients undergoing surgery. Although postoperative multimodal analgesia is widely practiced, opioids such as fentanyl are still one of the best analgesics. The analgesic response of fentanyl varies widely among individuals, probably due to genetic and nongenetic factors. Among genetic factors, single nucleotide polymorphisms (SNPs) may influence its analgesic response by altering the structure or function of genes involved in nociceptive, fentanyl pharmacodynamic, and pharmacokinetic pathways. Thus, it is necessary to comprehensively ascertain if the SNPs present in the aforementioned pathways are associated with interindividual differences in fentanyl requirement. In this study, we evaluated the association between 10 candidate SNPs in 9 genes and 24-hour postoperative fentanyl dose (primary outcome) and also with postoperative pain scores and time for first analgesia (secondary outcomes).A total of 257 South Indian women, aged 18-70 years, with American Society of Anesthesiologists (ASA) physical status I-III, undergoing major breast surgery under general anesthesia, were included in the study. Patients were genotyped for candidate SNPs using real-time polymerase chain reaction. All patients received a standardized intravenous fentanyl infusion through a patient-controlled analgesic (PCA) pump, and the 24-hour postoperative fentanyl dose requirement was measured using PCA.The median 24-hour postoperative fentanyl requirement was higher in rs1799971 carriers (G/G versus A/A + A/G-620 μg [500-700] vs 460 μg [400-580]) with a geometric mean (GM) ratio of 1.91 (95% confidence interval [CI], 1.071-1.327). The median 24-hour pain scores were higher in rs4680 carriers (A/G + A/A versus G/G-34 [30-38] vs 31 [30-38]) with a GM ratio of 1.059 (95% CI, 1.018-1.101) and were lower in rs1045642 carriers (A/A + A/G versus G/G-34 [30-38] vs 30 [30-34]) with a GM ratio of 0.936 (95% CI, 0.889-0.987). The median time for first analgesic was lower in rs734784 carriers [C/C versus T/T + C/T-240 minutes (180-270) vs 240 minutes (210-270)] with a GM ratio of 0.902 (95% CI, 0.837-0.972). Five of 9 clinical factors, namely, history of diabetes, hypertension, hypothyroidism, anesthesia duration, and intraoperative fentanyl requirement were associated with different outcomes individually (P.05) and were used to adjust the respective associations.The SNP opioid receptor mu-1 (OPRM1) (rs1799971) was associated with higher postoperative fentanyl requirement in South Indian patients undergoing major breast surgery. Twenty-four hour postoperative pain scores were higher in catechol-O-methyl transferase (COMT) (rs4680) carriers and lower in ATP binding cassette subfamily B member 1 (ABCB1) (rs1045642) carriers, whereas time for first analgesic was lower in potassium channel subunit 1 (KCNS1) (rs734784) carriers. However, these exploratory findings must be confirmed in a larger study.
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- 2022
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14. Can serum autoantibodies be a potential early detection biomarker for breast cancer in women? A diagnostic test accuracy review and meta-analysis
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Sreekumaran Nair, Aju Mathew, Suma Nair, PU Prakash Saxena, and Thejas R Kathrikolly
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Oncology ,medicine.medical_specialty ,business.industry ,Diagnostic Tests, Routine ,Serum autoantibodies ,Early detection ,Diagnostic test ,Medicine (miscellaneous) ,Breast Neoplasms ,medicine.disease ,Sensitivity and Specificity ,Breast cancer ,Meta-analysis ,Internal medicine ,Biomarker (medicine) ,Medicine ,Humans ,Female ,Cyclin B1 ,Tumor Suppressor Protein p53 ,business ,Biomarkers ,Early Detection of Cancer ,Autoantibodies - Abstract
Background The increasing incidence of breast cancer necessitates the need to explore alternate screening strategies that circumvent the setbacks of conventional techniques especially among population that report earlier age at diagnosis. Serum autoantibodies is one such potential area of interest. However, their ubiquitous presence across cancer types limits its applicability to any one specific type of cancer. This review was therefore carried out to explore and consolidate available evidence on autoantibodies for early detection of breast cancer and to identify those that demonstrated a higher sensitivity. Methods A diagnostic test accuracy (DTA) review was carried out to ascertain serum autoantibodies that could be used for early detection of breast cancer among women. All relevant articles that investigated the role of autoantibodies in early detection of breast cancer were included for the review. MEDLINE, Scopus, ProQuest, Ovid SP, and Cochrane Library were searched extensively for eligible studies. Quality of the included studies was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. RevMan 5.3 was used for exploratory and MetaDTA 2019 for hierarchical analyses. The review helped identify the most frequently investigated autoantibodies and a meta-analysis further consolidated the findings. Results A total of 53 articles were included for the final analysis that reported over a 100 autoantibodies that were studied for early detection of breast cancer in women. P53, MUC1, HER2, HSP60, P16, Cyclin B1, and c-Myc were the most frequently investigated autoantibodies. Of these P53, MUC1, HER2, and HSP60 exhibited higher summary sensitivity measures. While the individual pooled sensitivity estimates ranged between 10 and 56%, the panel sensitivity values reported across studies were higher with an estimated range of 60–87%. Conclusion Findings from the review indicate a higher sensitivity for an autoantibody panel in comparison to individual assays. A panel comprising of P53, MUC1, HER2, and HSP60 autoantibodies has the potential to be investigated as an early detection biomarker for breast cancer.
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- 2022
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15. A study on ectoparasites in Indian Mackerel, Rastrelliger kanagurta (Cuvier, 1817) of Thiruvananthapuram coast, South India
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Amrutha Shyla Suresh Suresh, Arya Unni, Balamurali Raghavan Pillai Sreekumaran Nair, and Binumon Thankachan Mangalathettu
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Gill ,Veterinary medicine ,Indian mackerel ,General Immunology and Microbiology ,biology ,Norileca indica ,Mucus production ,Marine fish ,Parasitic Infestation ,biology.organism_classification ,General Biochemistry, Genetics and Molecular Biology ,%22">Fish ,General Agricultural and Biological Sciences ,General Environmental Science ,Rastrelliger - Abstract
Parasitic infestation in marine fish requires urgent attention, especially those that infect economically important fishes, which affect their aesthetic quality and palatability. Ectoparasites in Indian Mackerel, Rastrelliger kanagurta (Cuvier, 1817), have not been studied well. Morphological and seasonal study of ectoparasites in R. kanagurta from the Thiruvananthapuram coast was conducted during March-August 2018. The study investigated three parasitic groups: Trichodinids, Digenean cysts (Centrocestus Looss, 1899), and Cymothoids (Norileca indica Milne Edwards, 1840 and Nerocila phaiopleura Bleeker, 1857) from R. kanagurta during the present study. Of the 240 fishes examined, the Trichodinids and digeneans showed 100% prevalence on the gill samples. Seasons had no significant effect on trichodinids and digeneans prevalence. However, parasitic Cmothoids fluctuated significantly according to the season. They showed greater prevalence during the pre-monsoon (45%) and least in monsoon (25%) due to environmental parameters like rainfall, salinity, and temperature. Trichodinids parasitized gills of R. kanagurta showed increased mucus production, paleness in the gills, and multifocal whitish areas. The Cymothoid infested fish showed lesions with the erosion of the epidermis and underlying dermis at the site of attachment. The noticeable changes were observed in the gill epithelium due to the encystment of digeneans. The Trichodinid ciliates and Heterophyid digenean cysts (Centrocestus Looss, 1899) are reported for the first time in R. kanagurta.
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- 2021
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16. Impact of views about knowledge and workplace relationships on tacit knowledge sharing
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Santhi Perumal and Shyam Sreekumaran Nair
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Knowledge management ,business.industry ,Process (engineering) ,Workplace relationships ,Library and Information Sciences ,Public good ,Management Information Systems ,Private good ,Appropriation ,Knowledge creation ,Tacit knowledge ,Management of Technology and Innovation ,Business and International Management ,business - Abstract
Tacit Knowledge Sharing (TKS) becomes vital for new knowledge creation. Knowledge creation process encourages the view of knowledge as a public good while knowledge appropriation process encourages...
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- 2021
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17. Characterization of cellular senescence in aging skeletal muscle
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Xu Zhang, Leena Habiballa, Zaira Aversa, Yan Er Ng, Ayumi E. Sakamoto, Davis A. Englund, Vesselina M. Pearsall, Thomas A. White, Matthew M. Robinson, Donato A. Rivas, Surendra Dasari, Adam J. Hruby, Anthony B. Lagnado, Sarah K. Jachim, Antoneta Granic, Avan A. Sayer, Diana Jurk, Ian R. Lanza, Sundeep Khosla, Roger A. Fielding, K. Sreekumaran Nair, Marissa J. Schafer, João F. Passos, and Nathan K. LeBrasseur
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Aging ,Neuroscience (miscellaneous) ,Geriatrics and Gerontology ,Article - Abstract
Senescence is a cell fate that contributes to multiple aging-related pathologies. Despite profound age-associated changes in skeletal muscle (SkM), whether its constituent cells are prone to senesce has not been methodically examined. Herein, using single cell and bulk RNA-sequencing and complementary imaging methods on SkM of young and old mice, we demonstrate that a subpopulation of old fibroadipogenic progenitors highly expresses p16(Ink4a) together with multiple senescence-related genes and, concomitantly, exhibits DNA damage and chromatin reorganization. Through analysis of isolated myofibers, we also detail a senescence phenotype within a subset of old cells, governed instead by p2(Cip1). Administration of a senotherapeutic intervention to old mice countered age-related molecular and morphological changes and improved SkM strength. Finally, we found that the senescence phenotype is conserved in SkM from older humans. Collectively, our data provide compelling evidence for cellular senescence as a hallmark and potentially tractable mediator of SkM aging.
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- 2022
18. Establishment of Tissue Biodistribution and Blood Clearance Rates of Intravenously Administered Radioactive 51Cr3+ in New Zealand White Rabbits
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Prathap Moothamadathil Baby, Pramod Kumar, Rajesh Kumar, Sanu Susan Jacob, Dinesh Rawat, Binu V Sreekumaran Nair, and Kalesh M Karun
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Multidisciplinary ,Biodistribution ,blood volume ,Trivalent chromium ,New Zealand white rabbits ,blood clearance - Abstract
Radioactive trivalent chromium (51Cr3+) is a known radiopharmaceutical used to tag plasma proteins, platelets and also for estimation of blood volume. Nevertheless, there exist insufficient reports with limited sample sizes concerning its clearance from blood and its biodistribution after intravenous administration. This study focused to understand clearance rate of 51Cr3+ from blood and analyze its biodistribution. For biodistribution, six adult New Zealand white albino rabbits were injected with 51Cr3+ through their marginal vein. Percentage clearance of 51Cr3+ from blood was calculated by recording radioactive counts obtained at 1, 58, 61, 120, 180 and 240 minutes post-administration in thirty-three adult New Zealand white albino rabbits. For evaluating 51Cr3+ biodistribution, organs were surgically removed from the rabbits and weighed. Radioactivity of the organs and urine were counted in a nucleonix gamma-ray spectrometer with a NaI scintillation detector. Data were expressed as cps/g. Average clearance of 51Cr3+ was 34% from the first to the 58 minute. Subsequent measurements for hourly clearance at 120, 180 and 240 minutes showed percentage reduction of radioactivity of 33, 14 and 8, respectively. Minimal specific activities were found in the muscle and brain. Spleen, lungs, liver and kidneys exhibited moderate radioactivity. Urine tracer-concentrations were found to be ten times more than that of plasma. From this study, it has been observed that clearance of 51Cr3+ from blood was faster initially which slowed down progressively and there displayed moderate uptake of 51Cr3+ by certain organs. Understanding pharmacokinetics of 51Cr3+ is relevant for its potential use as a diagnostic tool.
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- 2022
19. The impact of organisational culture on occupational stress: Comparison of the SME IT sectors in India and the UK
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John A. D. Aston, Eugene Kozlovski, and Sree Lekshmi Sreekumaran Nair
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Role stress ,Public economics ,media_common.quotation_subject ,Perspective (graphical) ,Quota sampling ,Organizational culture ,General Medicine ,Occupational stress ,Ambiguity ,Business ,Role conflict ,media_common - Abstract
The study's main aim is to examine the impact of organisational culture on occupational stress by comparing the IT sectors in India and the UK. The paper adopts the application of Denison’s model for studying the organisational culture, whereas role conflict, role ambiguity, role overload and role stress are considered to discuss occupational stress. Through snowball, convenience, purposive and quota sampling techniques, 62 respondents (31 from India and 31 from the UK) were targeted to attain a qualitative perspective through a semi-structured questionnaire. Results showed that there is an impact of organisational culture on occupational stress. Moreover, the impact is mainly evident in the Indian IT sector than the UK IT sector. Moreover, considering the impact of organisational culture on occupational stress, overall employees experience occupational stress, role overload, role conflict, role ambiguity and role stress. In contrasting economies, Indian IT sector employee’s experience role conflict, role overload, role ambiguity and role stress, whereas UK IT sector employees’ experience role ambiguity.
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- 2021
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20. The Impact of Job Satisfaction on Occupational Stress at the Managerial Level
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Sree Lekshmi Sreekumaran Nair, John Aston, and Eugene Kozlovski
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The present study examines the impact of job satisfaction on occupational stress of IT employees working in both developed and developing economies (India and the UK). Generally, occupational stress is considered to have the negative impact on the individual as well as the organization's performance. The study has adopted the application of the Spector JSS survey to consider the job satisfaction of the employees using the five-point Likert scale. The role conflict, role ambiguity, role overload, and role stress are considered in relation to occupational stress. Quantitative approach has been adopted by combining area cluster sampling, purposive and convenience sampling to gather 200 quantitative responses (100 from India and 100 from the UK) through questionnaire and analyzed through IBM SPSS 24.0. The results demonstrated that there is a significant impact of job satisfaction on the occupational stress in the IT sector of the UK and India.
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- 2022
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21. Handbook of Research on the Complexities and Strategies of Occupational Stress
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Sree Lekshmi Sreekumaran Nair
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- 2022
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22. 1301-P: The Effect of Insulin on α-Aminoadipic Acid Metabolism in Polycystic Ovary Syndrome (PCOS) Patients with Insulin Resistance
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ALICE Y. CHANG, ANEESH K. ASOKAN, DHANANJAY SAKRIKAR, ANTIGONI LALIA, MAI PETTERSON, and K. SREEKUMARAN NAIR
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Endocrinology, Diabetes and Metabolism ,Internal Medicine - Abstract
Population studies have shown that the α-Aminoadipic Acid (AAA) , a lysine metabolite, predicts future type 2 diabetes and AAA concentrations decrease following administration of insulin sensitizers. To determine whether women with PCOS and insulin resistance have altered lysine and AAA kinetics we compared age-matched 18 women with PCOS to 12 women without PCOS using stable isotopes labeled [α-15N1]-lysine and [13C1]-AAA to measure lysine and AAA kinetics. Baseline levels of AAA flux and lysine concentrations were higher in PCOS compared to women without PCOS. Insulin decreased the concentrations and flux values of lysine and AAA. The conversion of lysine to AAA and AAA-metabolic clearance rates were increased on insulin infusion in both groups (Table) . Insulin sensitivity was negatively correlated with lysine concentration (r = - 0.547, p < 0.05) and AAA flux (r= - 0.587, p < 0.05) . In conclusion, our results indicate that insulin sensitivity is a determinant of AAA metabolism and insulin administration modulate the kinetics thus reducing AAA concentration indicating that altered AAA and lysine metabolism may result from insulin resistance. Disclosure A.Y.Chang: None. A.K.Asokan: None. D.Sakrikar: Employee; The Binding Site. A.Lalia: None. M.Petterson: None. K.Nair: None. Funding National Institutes of Health (RAG62859)
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- 2022
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23. The Effect of Glucagon on Protein Catabolism During Insulin Deficiency - Exchange of Amino acids across Skeletal Muscle and the Splanchnic Bed
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Haleigh James, Wilson I. Gonsalves, Shankarappa Manjunatha, Surendra Dasari, Ian R. Lanza, Katherine A. Klaus, Adrian Vella, James C. Andrews, and K. Sreekumaran Nair
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Insulin, Regular, Human ,Endocrinology, Diabetes and Metabolism ,Proteolysis ,Internal Medicine ,Humans ,Insulin ,Amino Acids ,Glucagon ,Muscle, Skeletal - Abstract
Transient insulin deprivation with concurrent hyperglucagonemia is a catabolic state that can occur in type 1 diabetes. To evaluate glucagon’s catabolic effect in the setting of its glucogenic effect, we measured the regional exchanges of amino-metabolites across muscle and splanchnic beds in 16 healthy humans during either somatostatin followed by glucagon or a saline infusion alone. Despite a >2-fold increase in the regional exchange of amino-metabolites by glucagon, whole body kinetics and concentrations of amino acids (AAs) remained stable. Glucagon increased the splanchnic uptake of not only gluconeogenic but also essential amino acids (EAAs) while increasing their release from the muscle bed. Regional tracer-based kinetics and 3-methyl-histidine release indicate that EAA release from muscle is likely caused by reduced protein synthesis rather than increased protein degradation. Furthermore, many metabolites known to affect insulin action and metabolism were altered by hyperglucagonemia including increase in branched amino acids and keto acids of leucine and isoleucine in arterial plasma. Further, an increase in arterial concentrations of α-aminoadipic acid arising from increased conversion from lysine in the splanchnic bed was noted. These results demonstrate that hyperglucagonemia during hypoinsulinemia increases net muscle protein catabolism and substantially increases the exchange of amino metabolites across splanchnic and muscle beds.
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- 2022
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24. Modulatory effects of vitamin D on <scp>IL</scp> ‐33/ <scp>ST2</scp> immune axis in <scp>Guillain–Barré</scp> syndrome… quo vadis ?
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Praveen Pallathadka Sharma, Doniparthi V. Seshagiri, Madhu Nagappa, Thrinath Mullapudi, Nikhitha Sreenivas, Saikat Dey, Sumanth Shivaram, Rahul Wahatule, Vijay Kumawat, Binu V. Sreekumaran Nair, Sriganesh Kamath, Sanjib Sinha, Arun B. Taly, and Monojit Debnath
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Neurology ,Neurology (clinical) - Published
- 2022
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25. Analysis of postoperative complications following elective arthroscopic surgeries of the knee- a retrospective cohort study
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Ranjith Sreekumaran Nair, Rajiv Ramachandran Nair, Sandeep Munshi, Sriganesh Walkay, and Niranj Ganeshan Radhamony
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Surgery ,General Medicine - Abstract
Since their introduction, arthroscopic procedures have been increasingly utilized for the treatment of knee pathologies, especially Anterior Cruciate Ligament (ACL) reconstruction. Reduction of post-operative morbidity, shortened hospital stay and recovery period have all been identified as the benefits of arthroscopy. However, despite tremendous increase in the number of these procedures done, the postoperative complications associated have been infrequently analyzed. Hence, we performed this study to analyze the perioperative complications of arthroscopic ACL reconstruction.We performed a retrospective case control study from our hospital database from the cases performed in July 2015 to December 2016. We included 20 cases who developed postoperative complications within 30 days of the procedure and 60 controls operated during the same period who did not have any complications.The complications noted in the cases were surgical site infection (SSI), deep vein thrombosis (DVT), effusion and superficial infection. The risk factors associated with each complication were compared with the cases and analyzed.It was found that the lack of specialist physiotherapy, surgical prophylaxis and prolonged postoperative antibiotics were the major risk factors in the development of complications among our patients who underwent arthroscopic ACL reconstruction.
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- 2022
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26. Enhancement of anaerobic glycolysis – a role of PGC-1α4 in resistance exercise
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Jin-Ho Koh, Mark W. Pataky, Surendra Dasari, Katherine A. Klaus, Ivan Vuckovic, Gregory N. Ruegsegger, Arathi Prabha Kumar, Matthew M. Robinson, and K. Sreekumaran Nair
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Multidisciplinary ,Humans ,General Physics and Astronomy ,Resistance Training ,Anaerobiosis ,General Chemistry ,Glycolysis ,PPAR-beta ,General Biochemistry, Genetics and Molecular Biology ,Transcription Factors - Abstract
Resistance exercise training (RET) is an effective countermeasure to sarcopenia, related frailty and metabolic disorders. Here, we show that an RET-induced increase in PGC-1α4 (an isoform of the transcriptional co-activator PGC-1α) expression not only promotes muscle hypertrophy but also enhances glycolysis, providing a rapid supply of ATP for muscle contractions. In human skeletal muscle, PGC-1α4 binds to the nuclear receptor PPARβ following RET, resulting in downstream effects on the expressions of key glycolytic genes. In myotubes, we show that PGC-1α4 overexpression increases anaerobic glycolysis in a PPARβ-dependent manner and promotes muscle glucose uptake and fat oxidation. In contrast, we found that an acute resistance exercise bout activates glycolysis in an AMPK-dependent manner. These results provide a mechanistic link between RET and improved glucose metabolism, offering an important therapeutic target to counteract aging and inactivity-induced metabolic diseases benefitting those who cannot exercise due to many reasons.
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- 2022
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27. Chicken Bone Perforation 'The Missing Link' in a Bemused Breathless Octogenarian-A Case Report of Endoscopic Revivification
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Midhun Ramesh, Padmavathy Ramadoss, Ravi Sreekumaran Nair, and Abhilash Haridas
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medicine.medical_specialty ,Neurology ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Perforation (oil well) ,Stent ,030230 surgery ,medicine.disease ,Mediastinitis ,Endoscopy ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,medicine ,General Earth and Planetary Sciences ,030211 gastroenterology & hepatology ,Foreign body ,Hyponatremia ,business ,Complication ,General Environmental Science - Abstract
Esophageal perforation is a rare complication of foreign body ingestion. The most common foreign bodies causing esophageal perforation in adults are fish and chicken bones. We present the case of an octogenarian man with mild cognitive impairment presenting with respiratory complaints of dyspnoea and orthopnoea in the emergency room. He had hyponatremia induced confusion in addition to his mild cognitive impairment. The diagnosis for his clinical condition was not evident. Evaluation by imaging detected the "missing link" chicken bone as the cause of esophageal double perforation with mediastinitis and bilateral pleural effusion. Following multidisciplinary discussion, the minimally invasive endoscopic approach was decided as the definitive therapy. After medical stabilization in ICU, he underwent endoscopic retrieval of the foreign body followed by fully covered self-expandable metallic stenting. He recovered well and the stent removed after three weeks. Six months down the lane he is doing well and under neurology follow up for mild cognitive impairment. This clinical case shows the atypical, delayed perplexing presentation of esophageal foreign body in the elderly and the need for individualized treatment decision making for a successful outcome.
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- 2020
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28. Percutaneous balloon mitral valvotomy during pregnancy: A systematic review and meta‐analysis
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Ajith Ananthakrishna Pillai, Damini Sreerama, Latha Chaturvedula, Arun Keepanasseril, Anish Keepanasseril, Mahak Surana, Narayanapillai Sreekumaran Nair, and Kailash Moolchandani
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Balloon Valvuloplasty ,medicine.medical_specialty ,Pregnancy Complications, Cardiovascular ,law.invention ,Randomized controlled trial ,Pregnancy ,Risk Factors ,law ,Mitral valve ,Humans ,Mitral Valve Stenosis ,Medicine ,Mitral regurgitation ,business.industry ,Obstetrics ,Incidence (epidemiology) ,Pregnancy Outcome ,Obstetrics and Gynecology ,General Medicine ,medicine.disease ,Confidence interval ,medicine.anatomical_structure ,Meta-analysis ,Female ,business ,Cohort study - Abstract
INTRODUCTION The objective of this study was to systematically review the maternal and fetal outcomes in pregnant women who underwent percutaneous balloon mitral valvuloplasty (PBMV) during pregnancy. MATERIAL AND METHODS A search was conducted on MEDLINE and Embase databases to identify studies published between 2000 and 2018 that reported on maternal and fetal outcomes following PBMV performed in pregnancy. Randomized controlled trials, cohort studies, case-control studies, cross-sectional studies and case series with four or more pregnancies in which PBMV was performed during pregnancy were included. Reference lists from relevant articles were also hand-searched for relevant citations. A successful procedure was defined as one where there was a reported improvement in the valve area or reduction in the mitral valve gradient. A random effects model was used to derive pooled estimates of various outcomes and the final estimates were reported as percentages with a 95% confidence interval (95% CI). RESULTS Twenty-one observational studies reporting 745 pregnancies were included in the review, all of them having reported outcomes without a comparison group. Most of the studies fell into the low-risk category as determined using the Joanna Briggs Institute (JBI) critical appraisal checklist for case series. Most of the studies (86%) were reported from low- to middle-income countries and PBMV was mostly performed during the second trimester of pregnancy. Forty-three procedures (5.7%) were unsuccessful, nearly half (n = 19) of them reported among women with the severe subvalve disease (Wilkins subvalve score 3 or more). There were 11 maternal deaths among those with suboptimal valve anatomy (severe subvalve disease or Wilkin score >8). Mitral regurgitation was the most common cardiac complication (12.7%; 95% CI 7.3%-19.1%), followed by restenosis (2.4%; 95% CI 0.02%-7.2%). Pooled incidence of cesarean section was 12.1% (95% CI 3.6%-23.8%), preterm delivery 3.9% (95% CI 0.6%-9.0%), stillbirth 0.9% (95%CI 0.2%-2.2%) and low birthweight 5.4% (95% CI 0.2%-14.7%). CONCLUSIONS PBMV may be an effective and safe procedure for optimizing outcomes in pregnant women with mitral stenosis in the absence of severe subvalve disease.
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- 2020
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29. A diffusion tensor imaging study to compare normative fractional anisotropy values with patients suffering from Parkinson’s disease in the brain grey and white matter
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N. Sreekumaran Nair, K Prakashini, and Rahul P Kotian
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Pathology ,medicine.medical_specialty ,020205 medical informatics ,Biomedical Engineering ,Caudate nucleus ,Bioengineering ,02 engineering and technology ,Grey matter ,Corpus callosum ,Applied Microbiology and Biotechnology ,White matter ,03 medical and health sciences ,Nuclear magnetic resonance ,0302 clinical medicine ,mental disorders ,Centrum semiovale ,Fractional anisotropy ,0202 electrical engineering, electronic engineering, information engineering ,Medicine ,030212 general & internal medicine ,business.industry ,Putamen ,medicine.anatomical_structure ,nervous system ,business ,psychological phenomena and processes ,Biotechnology ,Diffusion MRI - Abstract
BackgroundDiffusion tensor imaging (DTI) appears as a sensitive method to study Parkinson’s disease (PD) pathophysiology and severity. Fractional anisotropy (FA) value is one of the scalar derivatives of DTI used to find out anisotropy within a voxel in a tissue and used for determining white matter integrity in aging and neurodegenerative diseases. We studied DTI derived FA in early PD subjects as their routine MRI scans were normal.Methods40 patients with early PD and 40 healthy controls were employed to evaluate changes in microstructural white and grey matter in the brain’s using DTI derived FA values. Comparison of FA values in the brain’s white and grey matter of patients with PD and age matched controls at the corpus callosum, centrum semiovale, pons, putamen, caudate nucleus, substantia nigra, cerebral peduncles and cerebellar peduncles, was done using a region of interest (ROI) technique, with b-value 1000s/mm2 and TE=100 milliseconds using 1.5T MRI system.ResultsPD patients showed differences in FA values in both the grey and white matter areas of the brain’s compared to healthy controls. Our study revealed the presence of damage in the substantia nigra, corpus callosum, putamen and cerebral peduncles mainly in the PD group.ConclusionOur findings indicate that DTI and region of interest (ROI) methods can be used in patients with early PD to study microstructural alterations mainly in the substantia nigra, putamen and corpus callosum.
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- 2020
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30. Nonstoichiometric Copper Sulfide Nanostructures at the Brass–Rubber Interface: Implications for Rubber Vulcanization Temperature in the Tire Industry
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A. Sreekumaran Nair, V. Subramanian, Tripti Ahuja, Anirban Som, M. P. Kannan, and Thalappil Pradeep
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Materials science ,Alloy ,Metallurgy ,Vulcanization ,chemistry.chemical_element ,Zinc ,engineering.material ,Copper ,law.invention ,Brass ,Copper sulfide ,chemistry.chemical_compound ,Natural rubber ,chemistry ,law ,visual_art ,visual_art.visual_art_medium ,engineering ,General Materials Science ,Tread - Abstract
Brass (which is an alloy of copper and zinc)-coated steel cords (BCSCs) in the form of belts are embedded in a rubber compound in radial tires (beneath the tread) to give stability and strength to ...
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- 2020
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31. Triple helix in practice in Indian HEIs using lens of academic patenting
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Ramesh Unnikrishnan, Shyam Sreekumaran Nair, and Santhi Perumal
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Strategy and Management ,0502 economics and business ,05 social sciences ,Optometry ,Lens (geology) ,Sociology ,0509 other social sciences ,Management Science and Operations Research ,050905 science studies ,050203 business & management ,Triple helix - Abstract
This paper studies the practice of triple helix phenomena in India using lens of academic patenting. In first part of the paper, using citation counts of patents assigned to Indian HEIs and BSE Sen...
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- 2020
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32. Photovoltaic Application of Rice Flake-Shaped ZnO Nanostructures
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S. Suresh, Sajini Vadukumpully, G. S. Anjusree, Gautam E. Unni, A. Sreekumaran Nair, V.P. Mahadevan Pillai, and V. N. Vineeth
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Materials science ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,law ,0103 physical sciences ,Solar cell ,Materials Chemistry ,Electrical and Electronic Engineering ,Niobium pentoxide ,Thin film ,010302 applied physics ,food and beverages ,Sputter deposition ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Dye-sensitized solar cell ,Chemical engineering ,chemistry ,0210 nano-technology - Abstract
Rice flake-shaped zinc oxide nanocrystallites were synthesized through a polymer-assisted, one-step hydrothermal route with an average size of 200–600 nm. The role of polymer concentration in the evolution of the nanostructure was evaluated, and the material was characterized using x-ray diffraction, electron microscopy, x-ray photoelectron spectroscopy, and ultraviolet–visible (UV–Vis) spectroscopy. The two-dimensional (2D) nanoflakes were demonstrated as promising photoanode material for dye-sensitized solar cells. Compared with hydrothermally prepared zinc oxide nanoparticles, the rice flake-shaped crystallites exhibited higher dye loading and light-scattering ability, which elicited a substantial increase in the light conversion efficiency. Thus, a fabricated solar cell with an active area of of 0.25 cm2 was provided with a niobium pentoxide blocking layer through radio frequency magnetron sputter coating at the zinc oxide/transparent conducting oxide interface to boost the efficiency up to 7.09% from 5.72% under 1.5-AM conditions.
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- 2020
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33. Diabetes Mellitus
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K. Sreekumaran Nair and Yogish C. Kudva
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medicine.medical_specialty ,business.industry ,Insulin ,medicine.medical_treatment ,Diabetes mellitus ,Perspective (graphical) ,medicine ,MEDLINE ,General Medicine ,Intensive care medicine ,business ,medicine.disease - Published
- 2020
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34. Surface modification of electrospun nanofibers of TiO2 in TiCl4 treatment for cactus-like TiO2 nanostructures
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Gautam E. Unni, A. Sreekumaran Nair, V. N. Vineeth, Sandeep Nandan, and Pillalamarri Srikrishnarka
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010302 applied physics ,Nanostructure ,Materials science ,Energy conversion efficiency ,Nanotechnology ,02 engineering and technology ,Tio2 nanofibers ,021001 nanoscience & nanotechnology ,01 natural sciences ,Electrospun nanofibers ,0103 physical sciences ,Surface modification ,0210 nano-technology ,Current density - Abstract
A cactus-like TiO2 nanostructure morphology was easily synthesized from electrospun TiO2 nanofibers as the template. The upgraded cactus-like TiO2 nanostructures were used as a photoanode material in dye-sensitized solar cells which showed 6.00 mA/cm2 higher current density and 10 mV higher open-circuit voltage to boost the overall power conversion efficiency to 5.21% from 2.13% for the solar cells having TiO2 nanofibrous photoanodes of the same active area and illumination conditions. In short, the result was a combination of the characteristics of both 0D and 1D nanostructures, i.e., higher surface area and improved electron transport. This was achieved through a simple TiCl4 treatment in room temperature conditions which has never resulted in any morphological advantages in any of the previous reports. Since these values were achieved without a separate TiCl4 treatment of the photoanode film, much higher performance is anticipated upon applying enhancement techniques. In a bird’s-eye view, this article provides insights into chemically modifying 1D nanostructures for an improved surface area and better results in their applications.
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- 2020
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35. Efficacy of pharmacological interventions in COVID-19: A network meta-analysis
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Sandhiya Selvarajan, Annuja Anandaradje, Santhosh Shivabasappa, Deepthy Melepurakkal Sadanandan, N. Sreekumaran Nair, and Melvin George
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Pharmacology ,Treatment Outcome ,Network Meta-Analysis ,Humans ,Pharmacology (medical) ,Antiviral Agents ,Dexamethasone ,Lopinavir ,Hydroxychloroquine ,Randomized Controlled Trials as Topic ,COVID-19 Drug Treatment - Abstract
To perform network meta-analysis for a head-to-head comparison of various interventions used in coronavirus disease 2019 (COVID-19) on mortality, clinical recovery, time to clinical improvement and the occurrence of serious adverse events.Systematic search was performed using online databases with suitable MeSH terms including coronavirus, COVID-19, randomized controlled trial, hydroxychloroquine, lopinavir/ritonavir, tocilizumab, remdesivir, favipiravir, dexamethasone and interferon-β. Data were independently extracted by 2 study investigators and analysed.Out of 1225 studies screened, 23 were included for qualitative and quantitative analysis. Among the drugs studied, dexamethasone reduces mortality by 10%, with a relative risk of 0.90 (95% confidence interval [0.82-0.97]) and increases clinical recovery by 6% (relative risk 1.06, 95% confidence interval [1.02-1.10]) compared to standard of care. Similarly, remdesivir administered for 10 days increased clinical recovery by 10%, reduced time to clinical improvement by 4 days and lowered the occurrence of serious adverse events by 27% as compared to standard of care.In comparison to standard of care, dexamethasone was found to increase clinical recovery and lower mortality; remdesivir was significantly associated with a lower risk of mortality as compared to tocilizumab and higher clinical recovery and shorter time to clinical improvement as compared to hydroxychloroquine and tocilizumab; remdesivir followed by tocilizumab were found to have lesser occurrence of serious adverse events in patients with moderate to severe COVID-19.
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- 2022
36. Transcriptomic Regulation of Muscle Mitochondria and Calcium Signaling by Insulin/IGF-1 Receptors Depends on FoxO Transcription Factors
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Gourav Bhardwaj, Christie M. Penniman, Katherine Klaus, Eric T. Weatherford, Hui Pan, Jonathan M. Dreyfuss, K. Sreekumaran Nair, C. Ronald Kahn, and Brian T. O’Neill
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insulin/IGF-1 receptors ,diabetes ,Physiology ,Physiology (medical) ,mitochondrial dysfunction ,QP1-981 ,RNA sequencing ,FoxO transcription factors ,muscle transcription - Abstract
Insulin and IGF-1, acting through the insulin receptor (IR) and IGF-1 receptor (IGF1R), maintain muscle mass and mitochondrial function, at least part of which occurs via their action to regulate gene expression. Here, we show that while muscle-specific deletion of IR or IGF1R individually results in only modest changes in the muscle transcriptome, combined deletion of IR/IGF1R (MIGIRKO) altered > 3000 genes, including genes involved in mitochondrial dysfunction, fibrosis, cardiac hypertrophy, and pathways related to estrogen receptor, protein kinase A (PKA), and calcium signaling. Functionally, this was associated with decreased mitochondrial respiration and increased ROS production in MIGIRKO muscle. To determine the role of FoxOs in these changes, we performed RNA-Seq on mice with muscle-specific deletion of FoxO1/3/4 (M-FoxO TKO) or combined deletion of IR, IGF1R, and FoxO1/3/4 in a muscle quintuple knockout (M-QKO). This revealed that among IR/IGF1R regulated genes, >97% were FoxO-dependent, and their expression was normalized in M-FoxO TKO and M-QKO muscle. FoxO-dependent genes were related to oxidative phosphorylation, inflammatory signaling, and TCA cycle. Metabolomic analysis showed accumulation of TCA cycle metabolites in MIGIRKO, which was reversed in M-QKO muscle. Likewise, calcium signaling genes involved in PKA signaling and sarcoplasmic reticulum calcium homeostasis were markedly altered in MIGIRKO muscle but normalized in M-QKO. Thus, combined loss of insulin and IGF-1 action in muscle transcriptionally alters mitochondrial function and multiple regulatory and signaling pathways, and these changes are mediated by FoxO transcription factors.
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- 2022
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37. Impact of Antecedent Infections on the Antibodies against Gangliosides and Ganglioside Complexes in Guillain-Barré Syndrome: A Correlative Study
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Madhu Nagappa, Debprasad Dutta, Monojit Debnath, DoniparthiV Seshagiri, BinuV Sreekumaran Nair, SumitK Das, Rahul Wahatule, Sanjib Sinha, Vasanthapuram Ravi, and ArunB Taly
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Neurology (clinical) - Abstract
Guillain-Barré Syndrome (GBS), an immune-mediated neuropathy, is characterized by antibodies against gangliosides/ganglioside complexes (GSCs) of peripheral nerves. Antecedent infections have been reported to induce antibodies that cross-react with the host gangliosides and thereby have a pivotal role in conferring an increased risk for developing GBS. Data pertaining to the impact of various antecedent infections, particularly those prevalent in tropical countries like India on the ganglioside/GSC antibodies is sparse. We aimed at exploring the association between six antecedent infections and the profile of ganglioside/GSC antibodies in GBS.Patients with GBS (n = 150) and healthy controls (n = 50) were examined for the serum profile of antibodies against GM1, GM2, GD1a, GD1b, GT1b, and GQ1b and their GSCs by ELISA. These antibodies were correlated with immunoreactivities againstThe frequencies of antibodies against six single gangliosides (This study for the first time shows an association between antecedent JE infection and ganglioside antibodies in GBS. This finding reinforces the determining role of antecedent infections on ganglioside antibody responses and the subsequent immunological processes in GBS.
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- 2022
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38. Application of Principal Component Analysis in Dealing with Multicollinearity in Modelling Clinical Data
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Akash Mishra, N Sreekumaran Nair, KT Harichandrakumar, VS Binu, and Santhosh Satheesh
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Clinical Biochemistry ,General Medicine - Abstract
Introduction: One of the stringent assumptions about covariates in the Cox hazard and Logistic regression modelling is that they should be independent. Incorporating correlated covariates as such into the model might distort the precision of the estimates due to multicollinearity. One way to deal with multicollinearity is by using Principal Component Analysis (PCA) technique. Aim: To demonstrate the application of PCA in dealing with correlated covariates while modelling time to event and casecontrol study data. Materials and Methods: This study was conducted at Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India, from February 2021 to January 2022. Two datasets were used for the demonstration i.e., data relates to a time to event outcome and a case-control study with binary outcome in which lipids were the correlated covariates. Three sets of Cox regression models were used to demonstrate change in hazard ratios with 95% Confidence Intervals (CI) for evaluating the effect of intervention at a different time of lipid measurement. Model I has evaluated treatment/ Body Mass Index (BMI) effect on the outcome by ignoring the effect of lipid parameters. Model II has evaluated treatment/ BMI effect on the outcome by incorporating lipid variables but ignoring multicollinearity. Model III has evaluated treatment/ BMI effect on the outcome by incorporating lipid variables through principal component analysis and thus adjusting for multicollinearity. Similarly, a logistic regression model was performed by using the same three sets of models to evaluate the effect of exposure (BMI). The comparability of lipids between the two groups for both datasets was tested using Hotelling’s T-squared statistic. Results: The lipids measured at 12th, 24th and 36th months between the two groups in the first data set as well as between cases and controls in the second data set were statistically significant. In the first dataset, at baseline, the Hazard Ratio’s (HR’s) were statistically similar irrespective of the models used; while decreasing successively with narrowing 95% CI’s as moving from model I to model III for the lipid measured at 12th, 24th and 36th months. Further, at 24th and 36th months, the HR in model-III found to be significant. In the second data set, the Odds Ratio (OR) were significant for all the three models and it was almost similar for model I and II but in model III it was elevated. Conclusion: The multicollinearity issue should be properly addressed before including correlated covariates in the Cox regression hazard and Logistic regression model. The PCA technique would be a favourable method.
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- 2022
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39. Echocardiographic nomograms and Z-scores for term Indian neonates
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Avinash Anantharaj, Vatsal Singh, Santhosh Satheesh, Sachit Ganapathy, Narayana-Pillai Sreekumaran Nair, Nivedita Mondal, Raja Selvaraj, and Neeraj Mishra
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Pediatrics, Perinatology and Child Health ,Cardiology and Cardiovascular Medicine - Published
- 2023
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40. TH-251. The Th17 pathway-related gene signatures modulate the risk and severity of Myasthenia gravis (MG)
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Nibu Varghese, Nikhitha Sreenivas, Sumanth Shivaram, Thrinath Mullapudi, Doniparthi V Seshagiri, Binu V Sreekumaran Nair, Monojith Debnath, and Madhu Nagappa
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Neurology ,Physiology (medical) ,Neurology (clinical) ,Sensory Systems - Published
- 2022
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41. Role of Zinc Oxide in the Compounding Formulation on the Growth of Nonstoichiometric Copper Sulfide Nanostructures at the Brass-Rubber Interface
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Kannan Murugesan Paulthangam, Anirban Som, Tripti Ahuja, Pillalamarri Srikrishnarka, Appukuttan Sreekumaran Nair, and Thalappil Pradeep
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General Chemical Engineering ,General Chemistry - Abstract
Tire technology has evolved substantially by the introduction of brass-coated steel cords (BCSCs) in radial tires. The durability of radial tires is dependent on the integrity of the brass-rubber interface composed predominantly of nonstoichiometric copper sulfide (Cu
- Published
- 2021
42. Re-examining Psychometric Properties of Fertility Problem Inventory: A Clinic-Based Study from India
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Ansha Patel, BinuValsalakumari Sreekumaran Nair, SumitKumar Das, Pratap Kumar, and PodilaSatya Venkata Narasimha Sharma
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Reproductive Medicine - Abstract
The fertility problem inventory (FPI) is one of the most widely used measures that tap the diverse psychological problems faced by infertile couples. Research on translated versions of FPI has also reflected its high clinical significance.This research aimed to explore the psychometric properties and the clinical validity of the original 46-item FPI in an Indian sample.This cross-sectional study was conducted in a tertiary hospital setup of a medical college.The original FPI was translated and pilot tested. The translated FPI was taken by 205 consenting infertile patients (113 women and 92 men). The psychometric properties of FPI were thus explored.Exploratory factor analysis with minimum residual method of extraction followed by oblimin rotation was performed. Perceived Stress Scale was used to establish the convergent validity of the newly developed FPI-Kannada version (FPI-K). A cut-off score for the FPI-K was obtained separately for males and females using ROC analysis in which hamilton anxiety scale was used as the gold standard.Only 32 items of the original FPI had factor loadings above 0.3 and overall six factors explained these items with a cumulative percentage variation of 32%. Overall Cronbach's alpha for FPI-K was 0.671 and it had a good convergent validity.The new FPI-K had 6 sub-domains and the clinical utility of same is discussed.
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- 2021
43. Metabolic responsiveness to training depends on insulin sensitivity and protein content of exosomes in insulin-resistant males
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Christian Herder, Hadi Al-Hasani, Stefan Lehr, Michael Roden, Karsten Müssig, Yanislava Karusheva, Maria Apostolopoulou, Sofiya Gancheva, Klaus Straßburger, Lucia Mastrototaro, Andreas S. Reichert, Dominik Pesta, Elisabetta De Filippo, Julia Szendroedi, Sonja Hartwig, K. Sreekumaran Nair, Daniel F. Markgraf, and Tomas Jelenik
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medicine.medical_specialty ,Multidisciplinary ,business.industry ,Insulin sensitivity ,Insulin resistant ,SciAdv r-articles ,Cardiorespiratory fitness ,Metabolism ,Cell Biology ,Microvesicles ,Interval training ,Protein content ,Endocrinology ,Internal medicine ,medicine ,Biomedicine and Life Sciences ,Health and Medicine ,business ,human activities ,Research Article - Abstract
Description, SEV may serve as new biomarkers for predicting the individual response of insulin sensitivity to exercising., High-intensity interval training (HIIT) improves cardiorespiratory fitness (VO2max), but its impact on metabolism remains unclear. We hypothesized that 12-week HIIT increases insulin sensitivity in males with or without type 2 diabetes [T2D and NDM (nondiabetic humans)]. However, despite identically higher VO2max, mainly insulin-resistant (IR) persons (T2D and IR NDM) showed distinct alterations of circulating small extracellular vesicles (SEVs) along with lower inhibitory metabolic (protein kinase Cε activity) or inflammatory (nuclear factor κB) signaling in muscle of T2D or IR NDM, respectively. This is related to the specific alterations in SEV proteome reflecting down-regulation of the phospholipase C pathway (T2D) and up-regulated antioxidant capacity (IR NDM). Thus, SEV cargo may contribute to modulating the individual metabolic responsiveness to exercise training in humans.
- Published
- 2021
44. Parametric evaluation of dynamic multistage centrifugal humidifier
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Shiva Kumar, Sampath Suranjan Salins, Prasanth Sreekumaran Nair, and Ana Tejero-González
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Mechanics of Materials ,Architecture ,Building and Construction ,Safety, Risk, Reliability and Quality ,Civil and Structural Engineering - Published
- 2022
- Full Text
- View/download PDF
45. Multivariate approach in analyzing medical data with correlated multiple outcomes: An exploration using ACCORD trial data
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K T Harichandrakumar, VS Binu, Santhosh Satheesh, N. Sreekumaran Nair, and Akash Mishra
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Microbiology (medical) ,Multivariate statistics ,Epidemiology ,media_common.quotation_subject ,Context (language use) ,Bivariate approach ,Bivariate analysis ,03 medical and health sciences ,0302 clinical medicine ,Statistics ,Statistical inference ,030212 general & internal medicine ,Analysis of correlated outcomes ,Normality ,Mathematics ,media_common ,Univariate analysis ,030219 obstetrics & reproductive medicine ,Public Health, Environmental and Occupational Health ,Univariate ,Infectious Diseases ,Sample size determination ,Univariate approach ,Public aspects of medicine ,RA1-1270 ,Simulation - Abstract
Background In clinical setting, to answer a research question, very often more than one outcome variables are used which are statistically correlated. Univariate analysis approach, which is commonly used in such context, violates the assumption of independence for correlated variables, while multivariate approach could give more robust and precise clinical decision by accounting this correlation. This paper is a demonstration of the change in statistical decision in multivariate approach compared to univariate approach in analysing medical data with multiple correlated outcome variables. Method ology: The data used in this paper was the ACCORD trial data and the variables were Systolic blood pressure (SBP) and Diastolic blood pressure (DBP) which are correlated. The condition of bivariate normality was checked after removing the outliers. We compared the differences in means of SBP and DBP separately between the groups at different follow up time points by univariate approach using unpaired ‘t' test and thereafter together by bivariate approach using Hotelling ‘T2'. Further the role of varied levels of correlation between SBP and DBP coupled with the variations in sample size in changing the statistical inference has been investigated. Robustness of these results were demonstrated through 1000 samples of simulated data from Accord trial data. Results The statistical decision regarding difference in means of either SBP or DBP between the two groups at baseline, 12th, 36th and 84th month in both univariate and bivariate approaches were similar. At baseline and 84th month the hypotheses were accepted and at 12th and 36th month the hypotheses were rejected with both the approaches. However at 60th and 72nd month the univariate and multivariate approach results contradicted each other which reflect the significance of correlation in modifying the inference. The analysis results further indicated that varied levels of correlation and sample size too modify the inference in bivariate approach and contradict univariate results. Conclusion Studies with multiple correlated outcomes, the multivariate approach which accounts this statistical correlation has potential to change statistical decisions and provide more precise results. Hence multivariate approach is recommended in such situations.
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- 2021
46. Rubber–rubber blends: A critical review
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A. Sreekumaran Nair, Sabu Thomas, Abitha Vayyaprontavida Kaliyathan, and KM Varghese
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Materials science ,Polymers and Plastics ,Polymer science ,General Chemical Engineering ,Organic Chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Natural rubber ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,0210 nano-technology - Abstract
The blending of different rubbers is one of the effective methods to achieve required performance properties in their final products. This article reviews the thermodynamic considerations of rubber–rubber blends and their filled systems. Factors affecting the rubber blend morphology (i.e. distribution mechanism of fillers, curatives and other compounding ingredients) and preparation techniques for rubber–rubber blends emphasizing their advantages and disadvantages are well discussed in this review. Microscopy is the field of interest to all material scientists. In the case of rubber blends, microscopy is an essential tool in order to understand the morphology, that is, size, shape and distribution of phases and filler particles in the rubber–rubber blend. In this review, selected scientific reports based on optical microscopy, electron microscopy and atomic force microscopy in rubber–rubber blends are discussed. Rubber material is a complex macromolecule; it has significant proportion of fillers, processing aids and curing agents; therefore, only a very few studies have been reported on the microscopic aspects of filled rubber–rubber blends. In particular, influence of rubber blend composition, fillers (micro and nano length scales) and processing additives on the morphology of rubber blends systems has not been systematically reviewed and discussed in the scientific literature. Therefore, in the present scenario, this review was thought of, which deals with the essential background to rubber–rubber blends, miscibility and morphological characterization of various rubber blend systems by microscopy. It is very important to add that although there is scattered information on these aspects in the scientific literature, to date a comprehensive review has not been published. The pros, cons, artefacts and the new challenges on the use of microscopy for the characterization of rubber–rubber blends are also discussed here.
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- 2019
- Full Text
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47. Evaluating Sanitization of Toothbrushes Using Various Decontamination Methods: A Meta-Analysis
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N. Sreekumaran Nair, Santosh Kumari Agrawal, T. V. Bhumika, and Sirjana Dahal
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Toothbrushing ,Ultraviolet Rays ,Dentistry ,Oral cavity ,Oral hygiene ,law.invention ,Nepal ,Tea Tree Oil ,law ,medicine ,Humans ,Garlic ,Microwaves ,Tea ,business.industry ,Chlorhexidine ,Tea tree oil ,General Medicine ,Human decontamination ,Oral Hygiene ,Disinfection ,Chemical agents ,Meta-analysis ,Toothbrush ,business ,medicine.drug - Abstract
Toothbrushes play an essential role in personal oral hygiene by effective plaque removal.However, they get heavily contaminated by bacteria, viruses, yeasts, and fungi which may originate from the oral cavity after every use as well as from the environment where they are stored. This systematic review was conducted to identify various decontamination interventions attempted scientifically and it summarizes the efficacy of each. Meta-analysis illustrated that the use of Ultra-violet rays and Microwave had a significant effect on reduction of the microbial count of a used toothbrush with a mean difference of -2.61 and CI (-4.66,-0.76) with I2=98%. When compared with non-active treatment group, the natural agents (garlic, green tree and tea-tree oil) proved to sterilize the toothbrushes effectively with mean difference of -483.34, CI (-914.79, -51.88) and I2=100%.In contrast, chlorhexidine showed the insignificant result with a mean difference of -347.55 and CI (-951.90, 256.80) with I2=100%. The evidence from this review suggests that decontaminating toothbrush reduces bacterial load. Toothbrushes exposed to radiation and natural agents proved to sanitize them effectively but chlorhexidine rendered insignificant results.Keywords: Chemical agent; disinfection; radiation; microbial load; natural agent; toothbrush.
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- 2019
- Full Text
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48. Insulin deficiency and intranasal insulin alter brain mitochondrial function: a potential factor for dementia in diabetes
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Priska Summer, Srinivas Gopala, Patrick M. Vanderboom, Gregory N. Ruegsegger, Surendra Dasari, K. Sreekumaran Nair, Katherine A. Klaus, Ian R. Lanza, Piotr Zabeilski, and Shankarappa Manjunatha
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Male ,0301 basic medicine ,medicine.medical_treatment ,medicine.disease_cause ,Biochemistry ,Mice ,Adenosine Triphosphate ,0302 clinical medicine ,Homeostasis ,Insulin ,Citrate synthase ,Phosphorylation ,Drug Implants ,biology ,Chemistry ,Brain ,Ketones ,Mitochondria ,mitochondrial fusion ,Biotechnology ,Monocarboxylic Acid Transporters ,medicine.medical_specialty ,Coumaric Acids ,Nerve Tissue Proteins ,Oxidative phosphorylation ,Diabetes Mellitus, Experimental ,03 medical and health sciences ,Internal medicine ,Diabetes mellitus ,Genetics ,medicine ,Animals ,Cytochrome c oxidase ,Lactic Acid ,Molecular Biology ,Administration, Intranasal ,Research ,medicine.disease ,Mice, Inbred C57BL ,Oxidative Stress ,030104 developmental biology ,Endocrinology ,Mitochondrial biogenesis ,biology.protein ,Dementia ,Energy Metabolism ,Reactive Oxygen Species ,Protein Processing, Post-Translational ,030217 neurology & neurosurgery ,Oxidative stress - Abstract
Despite the strong association between diabetes and dementia, it remains to be fully elucidated how insulin deficiency adversely affects brain functions. We show that insulin deficiency in streptozotocin-induced diabetic mice decreased mitochondrial ATP production and/or citrate synthase and cytochrome oxidase activities in the cerebrum, hypothalamus, and hippocampus. Concomitant decrease in mitochondrial fusion proteins and increased fission proteins in these brain regions likely contributed to altered mitochondrial function. Although insulin deficiency did not cause any detectable increase in reactive oxygen species (ROS) emission, inhibition of monocarboxylate transporters increased ROS emission and further reduced ATP production, indicating the causative roles of elevated ketones and lactate in counteracting oxidative stress and as a fuel source for ATP production during insulin deficiency. Moreover, in healthy mice, intranasal insulin administration increased mitochondrial ATP production, demonstrating a direct regulatory role of insulin on brain mitochondrial function. Proteomics analysis of the cerebrum showed that although insulin deficiency led to oxidative post-translational modification of several proteins that cause tau phosphorylation and neurofibrillary degeneration, insulin administration enhanced neuronal development and neurotransmission pathways. Together these results render support for the critical role of insulin to maintain brain mitochondrial homeostasis and provide mechanistic insight into the potential therapeutic benefits of intranasal insulin.—Ruegsegger, G. N., Manjunatha, S., Summer, P., Gopala, S., Zabeilski, P., Dasari, S., Vanderboom, P. M., Lanza, I. R., Klaus, K. A., Nair, K. S. Insulin deficiency and intranasal insulin alter brain mitochondrial function: a potential factor for dementia in diabetes.
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- 2019
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49. Natural rubber–SiO2 nanohybrids: interface structures and dynamics
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P J Xavier, A. Sreekumaran Nair, Abdul Sattar, and Archita Patnaik
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chemistry.chemical_classification ,Canonical ensemble ,Materials science ,Aqueous solution ,Nanocomposite ,02 engineering and technology ,General Chemistry ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electrostatics ,01 natural sciences ,0104 chemical sciences ,Molecular dynamics ,Chemical engineering ,chemistry ,Natural rubber ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Dispersion (chemistry) - Abstract
Homogeneous dispersion of silica nanoparticles (SiO2 NPs) in natural rubber (NR) is a key challenge for engineering high-performance nanocomposites and elucidation of their structure on a molecular basis. Towards this, the present work devised a novel route for obtaining 3D self-assembled SiO2 NP-NR nanocomposites under aqueous conditions and in the presence of Mg2+, by establishing a molecular bridge that clamped the negatively charged NR and SiO2 colloidal particles with a favoured NR-SiO2 NP hetero-aggregation. The characteristic NR-SiO2 NP hetero-aggregates displayed a decreased heat capacity with increase in the SiO2 mass-fraction, implying a restricted NR chain mobility. Such changes in the interfacial layers were tapped by 29Si NMR, DFT calculations and molecular dynamics simulations towards a mechanistic understanding of the structure and dynamics of the NR/SiO2 NP hybrid. Simple models were used to illustrate basic ideas; specific electrostatic interactions such as ion-dipole and H-bonding interactions proved to be the driving forces for the organized assembly leading to the NR-SiO2 hetero-aggregate over the NR-NR or SiO2 NP-SiO2 NP homo-aggregate. Molecular dynamics simulation of the aqueous canonical ensemble of the hybrid showed the stable molecular conformation to reveal a SiO2 NP spherical core encapsulated by a hydrophobically interconnected NR polymer layer as the outer shell, as a unique structural model. Specifically, the lipid end of the NR was involved electrostatically while the lysine end (the protein part of NR) H-bonded to the core silica cluster thereby restricting random aggregation. The calculated negative free energy changes for the hetero-aggregate composites via their vibrational and rotational spectra proved the spontaneity of composite formation.
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- 2019
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50. Comparison of Bayesian, Frequentist and Machine learning models for predicting the two-year mortality of patients diagnosed with squamous cell carcinoma of the oral cavity
- Author
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Sachit Ganapathy, K.T. Harichandrakumar, Prasanth Penumadu, Kadhiravan Tamilarasu, and N. Sreekumaran Nair
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Microbiology (medical) ,Infectious Diseases ,Epidemiology ,Public Health, Environmental and Occupational Health - Published
- 2022
- Full Text
- View/download PDF
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