Showing papers by "Central University of Kerala published in 2018"

Electrochemical Determination of Adrenaline Using MXene/Graphite Composite Paste Electrodes.

Abstract: MXene/graphite composite paste electrode (MXene/GCPE)-based electrochemical sensor has been fabricated for the detection of adrenaline. The electrode exhibits a sensitive response to adrenaline in phosphate buffer solution of pH 7.4, and its catalytic activity is much higher than that of the bare graphite paste electrode. The electron-transfer reaction of MXene/GCPE is a diffusion controlled process. The graph of concentration of adrenaline with the peak current exhibits two linearities, one in the lower and other in the higher concentration range with a detection limit of 9.5 nM. The simultaneous analyses of adrenaline, ascorbic acid, and serotonin reveal that the fabricated electrode could separate the overlapped cyclic voltammetric peaks of these ternary mixtures. This electrode has been further employed in the detection of adrenaline in pharmaceutical samples with 99.2-100.8% recoveries.

Gut Microbial Dysbiosis in Indian Children with Autism Spectrum Disorders.

Abstract: Autism spectrum disorder (ASD) is a term associated with a group of neurodevelopmental disorders. The etiology of ASD is not yet completely understood; however, a disorder in the gut-brain axis is emerging as a prominent factor leading to autism. To identify the taxonomic composition and markers associated with ASD, we compared the fecal microbiota of 30 ASD children diagnosed using Childhood Autism Rating Scale (CARS) score, DSM-5 approved AIIMS-modified INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD), and Indian Scale for Assessment of Autism (ISAA) tool, with family-matched 24 healthy children from Indian population using next-generation sequencing (NGS) of 16S rRNA gene amplicon. Our study showed prominent dysbiosis in the gut microbiome of ASD children, with higher relative abundances of families Lactobacillaceae, Bifidobacteraceae, and Veillonellaceae, whereas the gut microbiome of healthy children was dominated by the family Prevotellaceae. Comparative meta-analysis with a publicly available dataset from the US population consisting of 20 ASD and 20 healthy control samples from children of similar age, revealed a significantly high abundance of genus Lactobacillus in ASD children from both the populations. The results reveal the microbial dysbiosis and an association of selected Lactobacillus species with the gut microbiome of ASD children.

A peer-support lifestyle intervention for preventing type 2 diabetes in India: a cluster-randomized controlled trial of the Kerala Diabetes Prevention Program

Abstract: The major efficacy trials on diabetes prevention have used resource-intensive approaches to identify high-risk individuals and deliver lifestyle interventions. Such strategies are not feasible for wider implementation in low- and middle-income countries (LMICs). We aimed to evaluate the effectiveness of a peer-support lifestyle intervention in preventing type 2 diabetes among high-risk individuals identified on the basis of a simple diabetes risk score. Methods and findings: The Kerala Diabetes Prevention Program was a cluster-randomized controlled trial conducted in 60 polling areas (clusters) of Neyyattinkara taluk (subdistrict) in Trivandrum district, Kerala state, India. Participants (age 30–60 years) were those with an Indian Diabetes Risk Score (IDRS) ≥60 and were free of diabetes on an oral glucose tolerance test (OGTT). A total of 1,007 participants (47.2% female) were enrolled (507 in the control group and 500 in the intervention group). Participants from intervention clusters participated in a 12-month community-based peer-support program comprising 15 group sessions (12 of which were led by trained lay peer leaders) and a range of community activities to support lifestyle change. Participants from control clusters received an education booklet with lifestyle change advice. The primary outcome was the incidence of diabetes at 24 months, diagnosed by an annual OGTT. Secondary outcomes were behavioral, clinical, and biochemical characteristics and health-related quality of life (HRQoL). A total of 964 (95.7%) participants were followed up at 24 months. Baseline characteristics of clusters and participants were similar between the study groups. After a median follow-up of 24 months, diabetes developed in 17.1% (79/463) of control participants and 14.9% (68/456) of intervention participants (relative risk [RR] 0.88, 95% CI 0.66–1.16, p = 0.36). At 24 months, compared with the control group, intervention participants had a greater reduction in IDRS score (mean difference: −1.50 points, p = 0.022) and alcohol use (RR 0.77, p = 0.018) and a greater increase in fruit and vegetable intake (≥5 servings/day) (RR 1.83, p = 0.008) and physical functioning score of the HRQoL scale (mean difference: 3.9 score, p = 0.016). The cost of delivering the peer-support intervention was US$22.5 per participant. There were no adverse events related to the intervention. We did not adjust for multiple comparisons, which may have increased the overall type I error rate. Conclusions: A low-cost community-based peer-support lifestyle intervention resulted in a nonsignificant reduction in diabetes incidence in this high-risk population at 24 months. However, there were significant improvements in some cardiovascular risk factors and physical functioning score of the HRQoL scale

Nutritional Value of the Duckweed Species of the Genus Wolffia (Lemnaceae) as Human Food.

Abstract: Species of the genus Wolffia are traditionally used as human food in some of the Asian countries. Therefore, all 11 species of this genus, identified by molecular barcoding, were investigated for ingredients relevant to human nutrition. The total protein content varied between 20 and 30% of the freeze-dry weight, the starch content between 10 and 20%, the fat content between 1 and 5%, and the fiber content was ~25%. The essential amino acid content was higher or close to the requirements of preschool-aged children according to standards of the World Health Organization. The fat content was low, but the fraction of polyunsaturated fatty acids was above 60% of total fat and the content of n-3 polyunsaturated fatty acids was higher than that of n-6 polyunsaturated fatty acids in most species. The content of macro- and microelements (minerals) not only depended on the cultivation conditions but also on the genetic background of the species. This holds true also for the content of tocopherols, several carotenoids and phytosterols in different species and even intraspecific, clonal differences were detected in Wolffia globosa and Wolffia arrhiza. Thus, the selection of suitable clones for further applications is important. Due to the very fast growth and the highest yield in most of the nutrients, Wolffia microscopica has a high potential for practical applications in human nutrition.

Plant reference genes for development and stress response studies

Abstract: Many reference genes are used by different laboratories for gene expression analyses to indicate the relative amount of input RNA/DNA in the experiment. These reference genes are supposed to show least variation among the treatments and with the control sets in a given experiment. However, expression of reference genes varies significantly from one set of experiment to the other. Thus, selection of reference genes depends on the experimental conditions. Sometimes the average expression of two or three reference genes is taken as standard. This review consolidated the details of about 120 genes attempted for normalization during comparative expression analysis in 16 different plants. Plant species included in this review are Arabidopsis thaliana, cotton (Gossypium hirsutum), tobacco (Nicotiana benthamiana and N. tabacum), soybean (Glycine max), rice (Oryza sativa), blueberry (Vaccinium corymbosum), tomato (Solanum lycopersicum), wheat (Triticum aestivum), potato (Solanum tuberosum), sugar cane (Saccharum sp.), carrot (Daucus carota), coffee (Coffea arabica), cucumber (Cucumis sativus), kiwi (Actinidia deliciosa) and grape (Vitis vinifera). The list includes model and cultivated crop plants from both monocot and dicot classes. We have categorized plant-wise the reference genes that have been used for expression analyses in any or all of the four different conditions such as biotic stress, abiotic stress, developmental stages and various organs and tissues, reported till date. This review serves as a guide during the reference gene hunt for gene expression analysis studies.

Electrochemical oxidation of paracetamol in water by graphite anode: Effect of pH, electrolyte concentration and current density

Abstract: Paracetamol is one of the micropollutant in water and most frequently used drugs as moderate pain reliever. These micropollutants are serious threat to human and environment. In the present investigation, we made attempt to degrade the electrochemical oxidation of paracetamol in water by graphite as anode. Electrooxidation behavior of paracetamol at graphite anode was tested by cyclic voltammetry technique performed in the potential range of -1.0 to +1.0 V versus Ag/AgCl. The optimized conditions were obtained by varying different factors, such as electrolyte concentration (0.02-0.1 M), current density (3.1–7.1 mA/cm2), initial pH (4–8) and paracetamol concentration (20 mg L−1). The results showed that the maximum removal of paracetamol concentration, chemical oxygen demand (COD) and total organic carbon (TOC) reached >90%, >82% and >65% after 240 min electrolysis at an initial pH 4, having paracetamol concentration of 20 mg L−1 at a constant current density of 5.1 mA/cm2 with 0.1 M Na2SO4 supporting electrolyte. Different SO42- concentrations in water promoted the electro generation of strong mediator oxidant species, such as OH, SO4 - and S2O82- increasing the removal efficiency of paracetamol. The degradation of paracetamol and its mineralization trend were monitored by UV–vis spectrophotometric method and total organic carbon (TOC) analyzer, respectively. FT-IR spectra confirmed that the functional group changes after electrolysis of paracetamol. HPLC studies revealed the byproduct (hydroquinone, benzoquinone and carboxylic acid) formation during the electrolysis process. On the other hand, researchers are actively involved in ozonation, photocatalysis, activated charcoal and biological treatments etc., to remove/degrade micropollutant, which are major drawbacks for the implications.

Comparative mangrove metagenome reveals global prevalence of heavy metals and antibiotic resistome across different ecosystems.

Abstract: The mangrove ecosystem harbors a complex microbial community that plays crucial role in biogeochemical cycles. In this study, we analyzed mangrove sediments from India using de novo whole metagenome next generation sequencing (NGS) and compared their taxonomic and functional community structures to mangrove metagenomics samples from Brazil and Saudi Arabia. The most abundant phyla in the mangroves of all three countries was Proteobacteria, followed by Firmicutes and Bacteroidetes. A total of 1,942 genes were found to be common across all the mangrove sediments from each of the three countries. The mangrove resistome consistently showed high resistance to fluoroquinolone and acriflavine. A comparative study of the mangrove resistome with other ecosystems shows a higher frequency of heavy metal resistance in mangrove and terrestrial samples. Ocean samples had a higher abundance of drug resistance genes with fluoroquinolone and methicillin resistance genes being as high as 28.178% ± 3.619 and 10.776% ± 1.823. Genes involved in cobalt-zinc-cadmium resistance were higher in the mangrove (23.495% ± 4.701) and terrestrial (27.479% ± 4.605) ecosystems. Our comparative analysis of samples collected from a variety of habitats shows that genes involved in resistance to both heavy metals and antibiotics are ubiquitous, irrespective of the ecosystem examined.

Green Synthesis of High Temperature Stable Anatase Titanium Dioxide Nanoparticles Using Gum Kondagogu: Characterization and Solar Driven Photocatalytic Degradation of Organic Dye.

Abstract: The present study reports a green and sustainable method for the synthesis of titanium dioxide (TiO2) nanoparticles (NPs) from titanium oxysulfate solution using Kondagogu gum (Cochlospermum gossypium), a carbohydrate polymer, as the NPs formation agent. The synthesized TiO2 NPs were categorized by techniques such as X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy analysis, Raman spectroscopy, scanning electron microscope- Energy-dispersive X-ray spectroscopy (SEM-EDX), Transmission electron microscopy (TEM), High-resolution transmission electron microscopy (HR-TEM), UV-visible spectroscopy, Brunauer-Emmett-Teller (BET) surface area and particle size analysis. Additionally, the photocatalytic actions of TiO2 NPs were assessed with regard to their ability to degrade an organic dye (methylene blue) from aqueous solution in the presence of solar light. Various parameters affecting the photocatalytic activity of the TiO2 NPs were examined, including catalyst loading, reaction time, pH value and calcination temperature of the aforementioned particles. This green synthesis method involving TiO2 NPs explores the advantages of inexpensive and non-toxic precursors, the TiO2 NPs themselves exhibiting excellent photocatalytic activity against dye molecules.

Horizontal transfer of miR-23a from hypoxic tumor cell colonies can induce angiogenesis.

Abstract: Neo vessel formation by angiogenesis is an important event during many pathological conditions including cancer, where it is indispensable for tumor growth and survival. Although, various pro-angiogenic cytokines and soluble factors, secreted by tumor cells, have been reported to promote angiogenesis, recent studies have shown regulatory role of exosomes, secreted by tumor cells in the process of angiogenesis. These exosomes are capable of carrying nucleic acids, proteins, etc., as their cargo. Under the light of these facts and considering the presence of miRNAs, the non-coding RNAs capable of regulating target gene expression, as one of the major cargos in the exosomes, we investigated, whether exosomes derived from normoxic and hypoxic tumor cell colonies exhibit difference in levels of miR-23∼27∼24 cluster members and if so, to check the significance of their horizontal transfer on the process of angiogenesis. Results of our study showed that exosomes secreted by hypoxic tumor cell colonies possess significantly higher levels of miR23a and can induce angiogenesis. Further, we have shown that exosomes secreted by cells that ectopically over express miR23a is capable of inducing angiogenesis in different angiogenic model systems such as CAM, in ovo Xenograft and HUVEC models systems. Further, mechanistic analysis revealed that miR23a driven regulation of angiogenesis is brought about by down regulation of SIRT1 in the recipient cells. Collectively, the results presented here suggest that exosomal transfer of miR23a from tumor cell colonies can induce the process of angiogenesis by targeting SIRT1 in the recipient endothelial cells.

Experimental demonstration of non-local controlled-unitary quantum gates using a five-qubit quantum computer

Abstract: Local implementation of non-local quantum gates is necessary in a distributed quantum computer. Here, we demonstrate the non-local implementation of controlled-unitary quantum gates proposed by Eisert et al. (Phys Rev A 62:052317, 2000) using the five-qubit IBM quantum computer. We verify the fidelity and accuracy of the implementation through the techniques of quantum state and process tomographies.

Extraction of phenolic compounds with antioxidant potential from coconut (Cocos nucifera L.) testa and identification of phenolic acids and flavonoids using UPLC coupled with TQD-MS/MS

Abstract: Coconut testa, a brown skin covering of a coconut endosperm, is a rich source of phenolics. It is one of the by-products obtained in the coconut processing industries and currently underutilized despite being rich in phenolic compounds. A study was conducted to identify the suitable solvent system for maximum extractability of total phenolic content (TPC) and total flavonoid content (TFC) with antioxidant potential from the testa. Individual phenolic acids and flavonoids of different solvent extracts were also determined using UPLC-H class coupled with TQD-MS/MS. The TPC and TFC ranged from 4.9 to 167 mg GAE/g and 8.84–115 mg QE/g defatted testa, respectively; significant differences were observed for various solvent systems studied. Acidification of solvents significantly increased the extractability of TPC and reduced the extractability of TFC. A total of 28 phenolics comprising 16 phenolic acids and 12 flavonoids were identified. Protocatechuic acid, p-coumaric acid and ferulic acid are the major phenolic acids identified whereas, catechin, apigenin and kaempferol are the major flavonoids identified. In summary, this study proved that coconut testa is a natural source of multiple phenolics acids and flavonoids with potent antioxidant capacity, and it can be used as a natural source of antioxidants.

Application of high-salinity stress for enhancing the lipid productivity of Chlorella sorokiniana HS1 in a two-phase process

Abstract: Increased lipid accumulation of algal cells as a response to environmental stress factors attracted much attention of researchers to incorporate this stress response into industrial algal cultivation process with the aim of enhancing algal lipid productivity. This study applies high-salinity stress condition to a two-phase process in which microalgal cells are initially grown in freshwater medium until late exponential phase and subsequently subjected to high-salinity condition that induces excessive lipid accumulation. Our initial experiment revealed that the concentrated culture of Chlorella sorokiniana HS1 exhibited the intense fluorescence of Nile red at the NaCl concentration of 60 g/L along with 1 g/L of supplemental bicarbonate after 48 h of induction period without significantly compromising cultural integrity. These conditions were further verified with the algal culture grown for 7 days in a 1 L bottle reactor that reached late exponential phase; a 12% increment in the lipid content of harvested biomass was observed upon inducing high lipid accumulation in the concentrated algal culture at the density of 5.0 g DW/L. Although an increase in the sum of carbohydrate and lipid contents of harvested biomass indicated that the external carbon source supplemented during the induction period increased overall carbon assimilation, a decrease in carbohydrate content suggested the potential reallocation of cellular carbon that promoted lipid droplet formation under high-salinity stress. These results thus emphasize that the two-phase process can be successfully implemented to enhance algal lipid productivity by incorporating high-salinity stress conditions into the pre-concentrated sedimentation ponds of industrial algal production system.

Influence of Water Depth on Microalgal Production, Biomass Harvest, and Energy Consumption in High Rate Algal Pond Using Municipal Wastewater.

Abstract: The high rate algal ponds (HRAP) powered and mixed by a paddlewheel have been widely used for over 50 years to culture microalgae for the production of various products. Since light incidence is limited to the surface, water depth can affect microalgal growth in HRAP. To investigate the effect of water depth on microalgal growth, a mixed microalgal culture constituting three major strains of microalgae including Chlorella sp., Scenedesmus sp., and Stigeoclonium sp. (CSS), was grown at different water depths (20, 30, and 40 cm) in the HRAP, respectively. The HRAP with 20cm of water depth had about 38% higher biomass productivity per unit area (6.16 ± 0.33 g·m⁻²·d⁻¹) and required lower nutrients and energy consumption than the other water depths. Specifically, the algal biomass of HRAP under 20c m of water depth had higher settleability through larger floc size (83.6% settleability within 5 min). These results indicate that water depth can affect the harvesting process as well as cultivation of microalgae. Therefore, we conclude that water depth is an important parameter in HRAP design for mass cultivation of microalgae.

A group-based lifestyle intervention for diabetes prevention in low- and middle-income country: implementation evaluation of the Kerala Diabetes Prevention Program

Abstract: While several efficacy trials have demonstrated diabetes risk reduction through targeting key lifestyle behaviours, there is a significant evidence gap in relation to the successful implementation of such interventions in low- and middle-income countries (LMICs). This paper evaluates the implementation of a cluster randomised controlled trial of a group-based lifestyle intervention among individuals at high-risk of developing type 2 diabetes mellitus (T2DM) in the state of Kerala, India. Our aim is to uncover provider-, participant- and community-level factors salient to successful implementation and transferable to other LMICs. The 12-month intervention program consisted of (1) a group-based peer-support program consisting of 15 sessions over a period of 12 months for high-risk individuals, (2) peer leader (PL) training and ongoing support for intervention delivery, (3) diabetes education resource materials and (4) strategies to stimulate broader community engagement. The evaluation was informed by the RE-AIM and PIPE frameworks. Provider-level factors: Twenty-nine (29/30, 97%) intervention groups organised all 15 sessions. A 2-day PL training was attended by 51(85%) of 60 PLs. The PL handbook was found to be ‘very useful’ by 78% of PLs. Participant-level factors: Of 1327 eligible individuals, 1007(76%) participants were enrolled. On average, participants attended eight sessions. Sixty-eight percent rated their interest in group sessions as ‘very interested’, and 55% found the group sessions ‘very useful’ in making lifestyle changes. Inconvenient time (43%) and location (21%) were found to be important barriers for participants who did not attend any sessions. Community-level factors: Community-based activities reached to 41% of the participants for walking groups, 40% for kitchen garden training, and 31% for yoga training. PLs were readily available for support outside the sessions, as 75% of participants reported extracurricular contacts with their PLs. The commitment from the local partner institute and political leaders facilitated the high uptake of the program. A comprehensive evaluation of program implementation from the provider-, participant- and community-level perspectives demonstrates that the K-DPP program was feasible and acceptable in changing lifestyle behaviours in high-risk individuals. The findings from this evaluation will guide the future delivery of structured lifestyle modification diabetes programs in LMICs. Trial registration: Australia and New Zealand Clinical Trials Registry ACTRN12611000262909 . Registered 10 March 2011.

Dual responsive salen-type Schiff bases for the effective detection of L-arginine via a static quenching mechanism

Abstract: L-Arginine is one of the most important amino acids and plays a key role in diagnostic studies. Herein, we report four salen-type Schiff base fluorimetric/colorimetric sensors for the rapid detection of L-arginine. Substituents play a major role in the sensing mechanism of probes with the nitro-substituent bearing probe showing the highest efficiency. A 1 : 2 complexation between all the probes and the analyte was evidenced from the absorption titrations; and the fluorescence studies revealed a quenching phenomenon occurring during complex formation. From the life time measurements, the nature of quenching was found to be static and the formation of a ground state complex was confirmed. DFT calculations done at the B3LYP/TZVP level of theory corroborated the experimental findings and further established the proton transfer from the probe to the analyte during the complex formation.

Licarin A induces cell death by activation of autophagy and apoptosis in non-small cell lung cancer cells.

Abstract: Lung cancer has a relatively poor prognosis with a low survival rate and drugs that target other cell death mechanism like autophagy may help improving current therapeutic strategy. This study investigated the anti-proliferative effect of Licarin A (LCA) from Myristica fragrans in non-small cell lung cancer cell lines—A549, NCI-H23, NCI-H520 and NCI-H460. LCA inhibited proliferation of all the four cell lines in a dose and time dependent manner with minimum IC50 of 20.03 ± 3.12, 22.19 ± 1.37 µM in NCI-H23 and A549 cells respectively. Hence NCI-H23 and A549 cells were used to assess the ability LCA to induce autophagy and apoptosis. LCA treatment caused G1 arrest, increase in Beclin 1, LC3II levels and degradation of p62 indicating activation of autophagy in both NCI-H23 and A549 cells. In addition, LCA mediated apoptotic cell death was confirmed by MMP loss, increased ROS, cleaved PARP and decreased pro-caspase3. To understand the role of LCA induced autophagy and its association with apoptosis, cells were analysed following treatment with a late autophagy inhibitor-chloroquine and also after Beclin 1 siRNA transfection. Data indicated that inhibition of autophagy resulted in reduced anti-proliferative as well as pro-apoptotic ability of LCA. These findings confirmed that LCA brought about autophagy dependent apoptosis in non-small cell lung cancer cells and hence it may serve as a potential drug candidate for non-small cell lung cancer therapy.

Low genetic variation is associated with low mutation rate in the giant duckweed

Abstract: Mutation rate and effective population size (Ne) jointly determine intraspecific genetic diversity, but the role of mutation rate is often ignored. We investigate genetic diversity, spontaneous mutation rate and Ne in the giant duckweed (Spirodela polyrhiza). Despite its large census population size, whole-genome sequencing of 68 globally sampled individuals revealed extremely low within-species genetic diversity. Assessed under natural conditions, the genome-wide spontaneous mutation rate is at least seven times lower than estimates made for other multicellular eukaryotes, whereas Ne is large. These results demonstrate that low genetic diversity can be associated with large-Ne species, where selection can reduce mutation rates to very low levels, and accurate estimates of mutation rate can help to explain seemingly counter-intuitive patterns of genome-wide variation.

MoS2-ZnO nanocomposites as highly functional agents for anti-angiogenic and anti-cancer theranostics.

Abstract: Due to its excellent properties, 2D-MoS2 finds potential applications in the fields of electronics, optoelectronics, energy storage and conversion, biomedicine, etc. This work deals with the incorporation of ZnO into 2D-MoS2, its structural, morphological, optical, and magnetic studies and its application as an efficient cancer therapeutic agent. The MoS2–ZnO nanocomposite exhibits remarkable excitation wavelength dependent down-conversion and up-conversion photoluminescence. The observation of wasp-waisted magnetism in the MoS2–ZnO nanocomposite indicates the coupling of ZnO and MoS2 materials inducing multimodal population. The MoS2–ZnO nanocomposite showed cytotoxic properties with a safety index reaching up to ∼2. An in ovo xenograft assay revealed that the MoS2–ZnO nanocomposite retards tumor growth by specifically activating caspase-3 and thereby inducing cellular apoptosis. Moreover, the treatment of xenografts with the MoS2–ZnO nanocomposite down regulated the expression of major pro-angiogenic genes such as VEGF, VEGFR2 etc. thereby curtailing vascularization into the tumor intima. Treatment of tumor xenografts with the MoS2–ZnO nanocomposite caused reduced expression of mesenchymal specific genes and elevated expression of epithelial specific genes, implying a role of the MoS2–ZnO nanocomposite in retarding the process of epithelial to mesenchymal transition (EMT). This study highlights that the introduction of ZnO into MoS2 nanostructures offers a unique idea to design efficient MoS2-based multifunctional nanocomposites that provide opportunities in advanced biomedical and optoelectronic applications.