Browsing by Author "Unnikrishnan, S"

Now showing 1 - 5 of 5
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    Children (10-12 years age) of women with epilepsy have lower intelligence, attention and memory: Observations from a prospective cohort case control study
    (EPILEPSY RESEARCH, 2015) Gopinath, N; Muneer, AK; Unnikrishnan, S; Varma, RP; Thomas, SV
    Objective: To compare the cognitive outcome of children of women with epilepsy (CWE) with matched controls (CWO). Methods: CWE (10-12 years) under follow up in Kerala Registry of Epilepsy and Pregnancy (n= 190) were evaluated with WISC-IV, Trail Making Test (TMT), Rey Auditory Verbal Learning Test (RAVLT) and compared with age and sex matched children of women without epilepsy - CWO (n = 149) drawn from schools in the same region. The dosage was expressed as prescribed daily dose/daily-defined dose (PDD/DDD) ratio in order to make comparisons. Results: The Full Scale IQ of CWE (77.9 +/- 14.6) was 8.5 points lower than that of CWO (86.4 +/- 13.4), which was statistically significant (p=0.001). They performed lower on TMT Part A & B and RAVLT. The FSIQ mean +/- SD; PDD/DDD ratio and number of monotherapy exposure for different anti-epileptic drugs were phenobarbital: (74.5 +/- 14; 1.1 +/- 0.8; 22), valproate: (82.8 +/- 12.4; 0.3 +/- 0.1; 36), carbamazepine: (82.2 +/- 13.9; 0.6 +/- 0.3; 41), phenytoin: (82.6 +/- 13.5; 0.8 +/- 0.3; 11). The FSIQ for those exposed to phenobarbital was significantly (p =0.01) lower than others. The significant predictors of FSIQ differed at lower and higher ends of its spectrum. These predictors were low body mass index and low maternal education for FSIQ < 80 and low maternal education, low maternal IQ and high anti-epileptic drug dosage for FSIQ < 86. High anti-epileptic drug dosage, low maternal IQ and low paternal education were the predictors for FSIQ < 92. Significance: The IQ attention and memory were significantly lower for 10-12 year old CWE when compared to CWO. The important predictors of low FSIQ were antiepileptic drug dosage, maternal IQ and parental education. (C) 2015 Elsevier B.V. All rights reserved.
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    Constitution of FibrinBased Niche for In Vitro Differentiation of Adipose-Derived Mesenchymal Stem Cells to Keratinocytes
    (BioResearch Open Access, 2015-04) Unnikrishnan, S; Jayakumar, K; Krishnan, LK
    Epithelialization of chronic cutaneous wound is troublesome and may require use of skin/cell substitutes. Adipose- derived mesenchymal stem cells (ADMSCs) have immense potential as autologous cell source for treating wounds; they can cross the germ layer boundary of differentiation and regenerate skin. When multipotent adult stem cells are considered for skin regeneration, lineage committed keratinocytes may be beneficial to prevent undesirable post-transplantation outcome. This study hypothesized that ADMSCs may be directed to epidermal lineage in vitro on a specifically designed biomimetic and biodegradable niche. Cells were seeded on the test niche constituted with fibrin, fibronectin, gelatin, hyaluronic acid, laminin V, platelet growth factor, and epidermal growth factor in the presence of cell-specific differentiation medium (DM). The ADMSCs grown on bare tissue culture polystyrene surface in DM is designated DM-control and those grown in basal medium (BM) is the BM-control. Lineage commitment was monitored with keratinocyte-specific markers such as cytokeratin 14, cytokeratin 5, cytokeratin 19, and integrin a6 at the transcriptional/translational level. The in vitro designed biomimetic fibrin composite matrix may have potential application as cell transplantation vehicle.
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    Matrix-directed differentiation of human adipose derived mesenchymal stem cells to dermal-like fibroblasts that produce extracellular matrix
    (JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, 2015-04) Unnikrishnan, S; Jayakumar, K; Krishnan, LK
    Commercially available skin substitutes lack essential non-immune cells for adequate tissue regeneration of non-healing wounds. A tissue-engineered, patient-specific, dermal substitute could be an attractive option for regenerating chronic wounds, for which adipose-derived mesenchymal stem cells (ADMSCs) could become an autologous source. However, ADMSCs are multipotent in nature and may differentiate into adipocytes, osteocytes and chondrocytes in vitro, and may develop into undesirable tissues upon transplantation. Therefore, ADMSCs committed to the fibroblast lineage could be a better option for in vitro or in vivo skin tissue engineering. The objective of this study was to standardize in vitro culture conditions for ADMSCs differentiation into dermal-like fibroblasts which can synthesize extracellular matrix (ECM) proteins. Biomimetic matrix composite, deposited on tissue culture polystyrene (TCPS), and differentiationmedium(DM), supplemented with fibroblast-conditioned medium and growth factors,were used as a fibroblast-specific niche (FSN) for cell culture. For controls, ADMSCswere cultured on bare TCPS with either DM or basal medium (BM). Culture of ADMSCs on FSN upregulated the expression of differentiation markers such as fibroblast-specific protein-1 (FSP-1) and a panel of ECM molecules specific to the dermis, such as fibrillin-1, collagen I, collagen IV and elastin. Immunostaining showed the deposition of dermal-specific ECM,which was significantly higher in FSN compared to control. Fibroblasts derived from ADMSCs can synthesize elastin, which is an added advantage for successful skin tissue engineering as compared to fibroblasts fromskin biopsy. To obtain rapid differentiation of ADMSCs to dermal-like fibroblasts for regenerative medicine, a matrix-directed differentiation strategy may be employed. Copyright © 2014 John Wiley & Sons, Ltd
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    Synthesis and characterization of silver nanoparticle incorporated gelatin-hydroxypropyl methacrylate hydrogels for wound dressing applications
    (JOURNAL OF APPLIED POLYMER SCIENCE, 2017) Resmi, R; Unnikrishnan, S; Krishnan, LK; Krishnan, VK
    A replaceable wound cover which absorbs moisture and resist infection can be used to prevent development of chronic wounds. A major criterion for a replaceable wound dressing is nonadherence to cells to prevent pain upon removal. A major limitation of water absorbing hydrogels used in wound dressing applications is their poor mechanical strength. In this study, gelatin methacrylate (GelMA) was synthesized by reacting Type A porcine skin gelatin with methacrylic anhydride at 50 degrees C. Resultant GelMA monomer containing polyethylene glycol (PEG) protected silver nanoparticles were subsequently copolymerized with 2-hydroxypropyl methacrylate (HPMA) at room temperature by redox mechanism. This resulted in a hydrogel copolymer with optimum mechanical stability and moisture retention while inhibiting microbial contamination and FT-IR spectroscopy was used to confirm copolymer formation. Antimicrobial properties of the hydrogel using agar diffusion showed zone of inhibition against Staphylococcus aureus. Surface morphology was observed using scanning electron microscopy (SEM) and elemental analysis was carried out using energy-dispersive spectroscopy (EDS). Micro-computed tomography (micro-CT) analysis of the hydrogel showed enhancement in the pore size from around 32 m to 48-64 m after incorporation of silver nanoparticles. Degradation of the hydrogel was observed after 48 h when stored in PBS containing collagenase enzyme. In vitro cell culture experiments established absence of cytotoxicity in the hydrogel and nonadherence character to dermal fibroblasts. (C) 2016 Wiley Periodicals, Inc.
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    Synthesis and characterization of silver nanoparticle incorporated gelatinhydroxypropyl methacrylate hydrogels for wound dressing applications
    (Journal of Applied Polymer Science, 2016-12) Resmi, R; Unnikrishnan, S; Krishnan, LK; Krishnan, VK
    A replaceable wound cover which absorbs moisture and resist infection can be used to prevent development of chronic wounds. A major criterion for a replaceable wound dressing is nonadherence to cells to prevent pain upon removal. A major limitation of water absorbing hydrogels used in wound dressing applications is their poor mechanical strength. In this study, gelatin methacrylate (GelMA) was synthesized by reacting Type A porcine skin gelatin with methacrylic anhydride at 50 8C. Resultant GelMA monomer containing polyethylene glycol (PEG) protected silver nanoparticles were subsequently copolymerized with 2-hydroxypropyl methacrylate (HPMA) at room temperature by redox mechanism. This resulted in a hydrogel copolymer with optimum mechanical stability and moisture retention while inhibiting microbial contamination and FT-IR spectroscopy was used to confirm copolymer formation. Antimicrobial properties of the hydrogel using agar diffusion showed zone of inhibition against Staphylococcus aureus. Surface morphology was observed using scanning electron microscopy (SEM) and elemental analysis was carried out using energydispersive spectroscopy (EDS). Micro-computed tomography (micro-CT) analysis of the hydrogel showed enhancement in the pore size from around 32 m to 48–64 m after incorporation of silver nanoparticles. Degradation of the hydrogel was observed after 48 h when stored in PBS containing collagenase enzyme. In vitro cell culture experiments established absence of cytotoxicity in the hydrogel and nonadherence character to dermal fibroblasts