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Fulltext Antioxidant Potential in Different Parts and Callus of Gynura procumbens and Different Parts of Gynura bicolor

Krishnan V, Ahmad S, Mahmood M

Biomed Res Int, 2015;2015:147909.
PMID: 26491654 DOI: 10.1155/2015/147909

Plants from Gynura family was used in this study, namely, Gynura procumbens and Gynura bicolor. Gynura procumbens is well known for its various medicinal properties such as antihyperglycaemic, antihyperlipidaemic, and antiulcerogenic; meanwhile, G. bicolor remains unexploited. Several nonenzymatic antioxidants methods were utilized to study the antioxidant capacity, which include ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, total flavonoid content, total phenolic content, and ascorbic acid content determination. DPPH assay reveals G. procumbens shoot as the lowest (66.885%) and G. procumbens root as the highest (93.499%) DPPH radical inhibitor. In FRAP assay, reducing power was not detected in G. procumbens leaf callus (0.000 TEAC mg/g FW) whereby G. procumbens root exhibits the highest (1.103 TEAC mg/g FW) ferric reducing power. Total phenolic content and total flavonoid content exhibited similar trend for both the intact plants analysed. In all antioxidant assays, G. procumbens callus culture exhibits very low antioxidant activity. However, G. procumbens root exhibited highest phenolic content, flavonoid content, and ascorbic acid content with 4.957 TEAC mg/g FW, 543.529 QE µg/g FW, and 54.723 µg/g FW, respectively. This study reveals that G. procumbens root extract is a good source of natural antioxidant.
Evaluation of anti-histidine-rich protein 2 monoclonal antibodies, developed by using poly (N-isopropylacrylamide) as an adjuvant for malarial diagnostic application

Vishalkumar P, Jayaprakash NS, Desai PK, Krishnan V, Vijayalakshmi MA

Trop Biomed, 2020 Dec 01;37(4):1050-1061.
PMID: 33612757 DOI: 10.47665/tb.37.4.1050

OBJECTIVE: To evaluate the sensitivity and the stability of the monoclonal antibodies (Aa3c10, b10c1), against truncated Histidine-rich protein 2 (PfHRP2), developed using smart polymer, poly N-isopropylacrylamide, as adjuvant for malarial diagnostic applications in comparison with the available commercial antibodies.
METHODS: Two hybridoma clones (Aa3c10, b10c1) were used for the production of ascites in BALB/c mice. Purification of monoclonal antibodies from the ascites was carried out using affinity columns. The thermal stability study of monoclonal antibodies was done by storing it at 37°C and 45°C for thirty days. The stored antibodies were analyzed using SDS-PAGE and flow-through device where the antigenantibody interaction was visualized by Protein A colloidal gold solution. Sensitivity was determined by endpoint dilution ELISA and the dissociation constant by competitive ELISA. Sensitive pair optimization was done by sandwich ELISA using biotinylated antibodies. Prototype preparation for lateral flow assay had a colloidal gold-based detection system.
RESULTS: Thermal stability experiments showed that both mAbs (Aa3c10; b10c1) are stable up to thirty days at 45°C while the commercially available mAbs were stable up to fifteen days only. Compared to commercial antibodies, the mAb Aa3c10, showed the highest sensitivity in end-point titre. In sensitive pair optimization, it was observed that the mAb, b10c1, as a detector and the mAb, Aa3c10, as a capture antibody showed the highest absorbance to detect 50pg/ml PfHRP2 antigen. The prototype formulation of lateral flow assay using the mAbs (Aa3c10; b10c1) showed good reactivity with WHO panel and no false-positive results were observed with twenty clinically negative samples and five P. vivax positive samples.
CONCLUSIONS: The novel monoclonal antibodies (Aa3c10, b10c1) against truncated PfHRP2, could be a strong potential candidates that can be included in making RDTs with better sensitivity and stability.
Fulltext Leptin and Associated Mediators of Immunometabolic Signaling: Novel Molecular Outcome Measures for Neurostimulation to Treat Chronic Pain

Kinfe TM, Buchfelder M, Chaudhry SR, Chakravarthy KV, Deer TR, Russo M, et al.

Int J Mol Sci, 2019 Sep 24;20(19).
PMID: 31554241 DOI: 10.3390/ijms20194737

Chronic pain is a devastating condition affecting the physical, psychological, and socioeconomic status of the patient. Inflammation and immunometabolism play roles in the pathophysiology of chronic pain disorders. Electrical neuromodulation approaches have shown a meaningful success in otherwise drug-resistant chronic pain conditions, including failed back surgery, neuropathic pain, and migraine. A literature review (PubMed, MEDLINE/OVID, SCOPUS, and manual searches of the bibliographies of known primary and review articles) was performed using the following search terms: chronic pain disorders, systemic inflammation, immunometabolism, prediction, biomarkers, metabolic disorders, and neuromodulation for chronic pain. Experimental studies indicate a relationship between the development and maintenance of chronic pain conditions and a deteriorated immunometabolic state mediated by circulating cytokines, chemokines, and cellular components. A few uncontrolled in-human studies found increased levels of pro-inflammatory cytokines known to drive metabolic disorders in chronic pain patients undergoing neurostimulation therapies. In this narrative review, we summarize the current knowledge and possible relationships of available neurostimulation therapies for chronic pain with mediators of central and peripheral neuroinflammation and immunometabolism on a molecular level. However, to address the needs for predictive factors and biomarkers, large-scale databank driven clinical trials are needed to determine the clinical value of molecular profiling.
Fulltext The longitudinal relationship between nutritional status and anaemia among Malaysian adolescents

Krishnan V, Zaki RA, Nahar AM, Jalaludin MY, Majid HA

Lancet Reg Health West Pac, 2021 Oct;15:100228.
PMID: 34528009 DOI: 10.1016/j.lanwpc.2021.100228

Introduction: The triple burden of malnutrition characterised by stunting and wasting, overweight/obesity, and anaemia experienced by Malaysians causes severe and long-lasting damage during the period of development and rapid growth, particularly in adolescence. This study aimed to demonstrate the trend of anaemia prevalence and to determine its longitudinal association with nutritional status and lifestyle among Malaysian adolescents.
Method: The study involved secondary data analysis from the Malaysian Health and Adolescents Longitudinal Research Team (MyHeART) study. A closed cohort secondary data analysis was performed from the dynamic cohort of 528 adolescents (male = 151; female = 377) aged 13 years attending secondary school who were followed up at 15 and 17 years. Anaemia status was determined by haemoglobin level < 12g/dL based on FBC, and iron deficiency anaemia (IDA) was determined when the Mentzer Index < 13. A generalised estimating equation (GEE) was constructed to investigate the longitudinal relationship between nutritional status and lifestyle on anaemia status over five years.
Results: The trend of anaemia prevalence increased significantly across the age group (7•9%; 95% CI: 2•3-11•1, 13•9%; 95% CI: 10•8-15•7 and 15•8%; 95% CI: 3•8-23•1) at 13, 15 and 17 years, respectively, especially among females. The trend of anaemia prevalence among females, also increased significantly across the age group (11.1%;95% CI:6.7-17.8, 15.7%;95% CI:11.4-21.3, 23.1%;95% CI:16.8-31.0). A similar trend was noted for the prevalence of IDA among those who were anaemic (66•5%; 95% CI: 40•4-85•3, 72•2%;95% CI: 54•8-85•4, 76•3%; 95% CI: 59•2-87•7). A longitudinal analysis using GEE revealed that adolescents who did not meet the Recommended Nutrient Intake (RNI) for total iron intake per day were significantly associated with anaemia (RR=1•517;95% CI: 1•012-2•275; p=0•044) and IDA (RR=1•776;95% CI: 1•225-2•57; p= 0•002).
Conclusion: The overall trend of anaemia among adolescents is in increasing trend and anaemia is prevalent among female adolescents in this study. It is crucial to understand that the current fortification strategy may need to be revisited, and robust intervention programmes are necessary and should be sex specific.
Plant extract as environmental-friendly green catalyst for the reduction of hexavalent chromium in tannery effluent

Johnson P, Loganathan C, Krishnan V, Sakayanathan P, Raji V, Vijayan S, et al.

Environ Technol, 2018 Jun;39(11):1376-1383.
PMID: 28488473 DOI: 10.1080/09593330.2017.1329355

The aqueous extract of various plants like Coriandrum sativum (AECS), Alternanthera tenella colla (AEAT), Spermacoce hispida (AESH) and Mollugo verticillata (AEMV) was studied for its hexavalent chromium (CrVI) reduction property. Even though antioxidant activity was present, AEAT, AESH and AEMV did not reduce CrVI. AECS showed rapid and dose-dependent CrVI reduction. The efficient reduction of 50 mg/L of CrVI using AECS was attained in the presence of 250 µg/mL of starting plant material, incubating the reaction mixture at pH 2, 30°C and agitation at 190 rpm. Under such conditions, about 40 mg/L of CrVI was reduced at 3 h of incubation. FT-IR analysis revealed the involvement of phenols, alcohols, alpha-hydroxy acid and flavonoids present in the AECS for the CrVI reduction. These results indicate that not all the plant extracts with rich antioxidants are capable of reducing CrVI. Using the conditions standardized in the present study, AECS reduced about 80% of CrVI present in the tannery effluent. These results signify the application of AECS as an eco-friendly method in the wastewater treatment.
Rapid biosynthesis of Bauhinia variegata flower extract-mediated silver nanoparticles: an effective antioxidant scavenger and α-amylase inhibitor

Johnson P, Krishnan V, Loganathan C, Govindhan K, Raji V, Sakayanathan P, et al.

Artif Cells Nanomed Biotechnol, 2018 Nov;46(7):1488-1494.
PMID: 28885044 DOI: 10.1080/21691401.2017.1374283

Silver nanoparticles (AgNPs) were biosynthesized using Bauhinia variegata flower extract (BVFE). The BVF-AgNPs was found to be spherical shaped with the size of 5-15 nm. The phytoconstituents analysis and FTIR spectrum indicated that bioactive compounds like, phenols, flavonoids, benzophenones, nitro compounds, aromatics and aliphatic amines from BVFE might absorb on the surface of BVF-AgNPs. The synthesized BVF-AgNPs showed potent antioxidant property and α-amylase enzyme activity inhibition. The IC50 value of BVF-AgNPs was found to be 4.64 and 16.6 µg/ml for DPPH and ferric reducing power assay, respectively. The IC50 value of BVF-AgNPs for α-amylase inhibition was found to be 38 µg/ml. The Ki value of BVF-AgNPs for α-amylase inhibitory effect was found to be 21 µg/ml with the non-competitive mode of inhibition. These results suggest that BVF-AgNPs might be an effective nano-drug to treat diabetic conditions.
Fulltext The impact factor of an open access journal does not contribute to an article's citations

Chua SK, Qureshi AM, Krishnan V, Pai DR, Kamal LB, Gunasegaran S, et al.

F1000Res, 2017;6:208.
PMID: 28649365 DOI: 10.12688/f1000research.10892.1

Background Citations of papers are positively influenced by the journal's impact factor (IF). For non-open access (non-OA) journals, this influence may be due to the fact that high-IF journals are more often purchased by libraries, and are therefore more often available to researchers, than low-IF journals. This positive influence has not, however, been shown specifically for papers published in open access (OA) journals, which are universally accessible, and do not need library purchase. It is therefore important to ascertain if the IF influences citations in OA journals too. Methods 203 randomized controlled trials (102 OA and 101 non-OA) published in January 2011 were included in the study. Five-year citations for papers published in OA journals were compared to those for non-OA journals. Source papers were derived from PubMed. Citations were retrieved from Web of Science, Scopus, and Google Scholar databases. The Thompson-Reuter's IF was used. Results OA journals were found to have significantly more citations overall compared to non-OA journals (median 15.5 vs 12, p=0.039). The IF did not correlate with citations for OA journals (Spearman's rho =0.187, p=0.60). The increase in the citations with increasing IF was minimal for OA journals (beta coefficient = 3.346, 95% CI -0.464, 7.156, p=0.084). In contrast, the IF did show moderate correlation with citations for articles published in non-OA journals (Spearman's rho=0.514, p<0.001). The increase in the number of citations was also significant (beta coefficient = 4.347, 95% CI 2.42, 6.274, p<0.001). Conclusion It is better to publish in an OA journal for more citations. It may not be worth paying high publishing fees for higher IF journals, because there is minimal gain in terms of increased number of citations. On the other hand, if one wishes to publish in a non-OA journal, it is better to choose one with a high IF.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.

Autophagy, 2016;12(1):1-222.
PMID: 26799652 DOI: 10.1080/15548627.2015.1100356
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1

Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.

Autophagy, 2021 Jan;17(1):1-382.
PMID: 33634751 DOI: 10.1080/15548627.2020.1797280

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.