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Mitochondrial amidoxime-reducing component 1 p.Ala165Thr increases protein degradation mediated by the proteasome. Liver Int 2024; 44:1219-1232. [PMID: 38375985 DOI: 10.1111/liv.15857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/21/2024]
Abstract
OBJECTIVE Metabolic dysfunction-associated steatotic liver disease (MASLD) is a global health concern with no effective and specific drug treatment available. The rs2642438 minor allele in mitochondrial amidoxime-reducing component 1 (MARC1) results in an aminoacidic substitution (p.Ala165Thr) and associates with protection against MASLD. However, the mechanisms behind this protective effect are unknown. In this study, we examined the consequences of this aminoacidic substitution on protein stability and subcellular localization. METHODS We overexpressed the human MARC1 A165 (wild-type) or 165T (mutant) in vivo in mice and in vitro in human hepatoma cells (HepG2 and HuH-7), generated several mutants at position 165 by in situ mutagenesis and then examined protein levels. We also generated HepG2 cells stably overexpressing MARC1 A165 or 165T to test the effect of this substitution on MARC1 subcellular localization. RESULTS MARC1 165T overexpression resulted in lower protein levels than A165 both in vivo and in vitro. Similarly, any mutant at position 165 showed lower protein levels compared to the wild-type protein. We showed that the 165T mutant protein is polyubiquitinated and its degradation is accelerated through lysine-48 ubiquitin-mediated proteasomal degradation. We also showed that the 165T substitution does not affect the MARC1 subcellular localization. CONCLUSIONS This study shows that alanine at position 165 in MARC1 is crucial for protein stability, and the threonine substitution at this position leads to a hypomorphic protein variant due to lower protein levels. Our result supports the notion that lowering hepatic MARC1 protein level may be a successful therapeutic strategy for treating MASLD.
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Synthesis and Characterization of Zn(II) Complex of 4-chloro-2-(((2-phenoxyphenyl)imino)methyl)phenol and its Biological Efficacies: DNA Interaction, ADMET, DFT and Molecular Docking Study. J Fluoresc 2024:10.1007/s10895-024-03687-9. [PMID: 38613713 DOI: 10.1007/s10895-024-03687-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 03/22/2024] [Indexed: 04/15/2024]
Abstract
Condensing 2-phenoxyaniline with 5-chlorosalicyldehyde under reflux conditions, a 4-chloro-2-(((2-phenoxyphenyl)imino)methyl)phenol Schiff base has been Synthesized. A zinc complex was synthesized by combining the ligand in a 1:1 molar ratio with zinc sulphateheptahydrate. Mass spectroscopy, NMR, infrared, and elemental analysis were used to characterize the ligand and zinc complex. By measuring the molar conductance, the non-electrolytic character of the complex was confirmed. The zinc ion is coordinated in a pentadentate manner, according to an IR and NMR investigation. Viscosity measurements, absorption and fluorescence spectroscopy were utilized to examine the complex's interaction with CT (calf thymus) DNA. Furthermore, the ligand and complex's ADMET characteristics were ascertained through the use of ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) study. Calculation of the different electronic parameters of the optimized structure through Density Functional Theory (DFT) indicated the stability of the Zn(II) complex. Molecular docking study reflected the future opportunity for the consideration of Zn(II) complex to fight against Alzheimer and Glaucoma diseases.
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Synthesis of Novel [{(2-Amino-5-Nitro-N-[(E)-Thiophen-2-yl-Methylidene]Aniline-κ 3N 1:N 4:S)(Sulphato-κ 2O 1:O 3)}Zinc(II)] Complex with Physico-Chemical and Biological Perspective Exploration: A Combined Experimental and Computational Studies. J Fluoresc 2024:10.1007/s10895-024-03612-0. [PMID: 38393498 DOI: 10.1007/s10895-024-03612-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 02/01/2024] [Indexed: 02/25/2024]
Abstract
A novel metal complex was synthesized using freshly prepared 2-Amino-5-nitro-N-[(E)-thiophen-2-yl-methylidene]aniline ligand with Zn (II) sulphate heptahydrate in a 1:1 molar ratio. The ligand and the complex were characterized using different spectroscopic techniques, and the complex was assigned a distorted square pyramidal geometry. Additionally, DNA binding assays and antibacterial activity were used to assess the biological perspectives for the synthesized complex, including the ligand and complex which was further confirmed by molecular docking. Fluorescence Spectroscopy, viscosity measurement, and adsorption measurement were used to investigate the interaction of the Zn (II) complex with CT-DNA. A comparative in vitro antibacterial activity study against Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, and Staphylococcus aureus strains were studied with free ligand and Zn (II) metal complex. The stable geometry of the complex was additionally established through computational simulation utilizing density functional theory, which was followed by the calculation of several electronic properties. The ADMET characteristics of the complex and ligand were also assessed using ADMET analysis. The in-silico ADMET properties pointed to a significant drug-likeness feature in the synthesized compounds, based on the Lipinski criteria.
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Nasal MRSA carriage is a risk factor for development of antibiotic resistance in diabetic foot ulcers and is significantly higher than diabetic and non-diabetic individuals without foot ulcer. BMC Infect Dis 2023; 23:729. [PMID: 37884870 PMCID: PMC10601299 DOI: 10.1186/s12879-023-08673-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/06/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND Diabetic foot ulcer (DFU) is a major complication of diabetes often impacted by polymicrobial infection in the wound site. Diabetic patients are immunocompromised in nature and hence vulnerable to infection once the skin barrier is breached. Microbiological culture-based methods show that Staphylococcus aureus (SA) is the most frequently isolated bacteria from the DFU wounds. SA and its most clinically important antibiotic resistant variant methicillin-resistant S. aureus (MRSA) are commonly found in the nasal vestibule and colonization of SA as well as MRSA in any wound site can aggravate the condition. We hypothesize that the presence of nasal MRSA carriage can serve as a potential risk factor contributing to the emergence of antibiotic resistance in diabetic foot ulcer wounds. METHODS In the present study, we have compared the carriage of SA and MRSA in nasal cavity and foot skin among DFU patients (D+F+, n = 50), diabetic patients without any ulcer (D+F-, n = 50), and healthy controls (D-F-, n = 40) by using bacterial culture and PCR based methods. The D+F+, D+F- and D-F-individuals were further categorized based on the presence or absence of MRSA and clinical parameters were compared between MRSA+ ve and MRSA-ve individuals in each of the three groups mentioned above. RESULTS Our results show that, (a) nasal MRSA carriage is significantly higher (p < 0.05) in D+F+ group than the D+F- and D-F- and significantly associated with wound MRSA carriage in D+ F+ individuals (O.R. = 4.09; 95% C.I. = 1.12-15.05) and (b) the HbA1C level is significantly higher (p < 0.02) in wound MRSA positive, compared to MRSA negative D+F+ patients. Interestingly more than half of the MRSA (64%) isolated from DFU wound were identified to be multidrug resistant. CONCLUSION These findings strongly suggest that nasal MRSA carriage can act as a risk factor for development of antibiotic resistance in diabetic foot ulcers and it is therefore important to screen nasal and wound sites of these patients regularly. We have also developed a rapid multiplex PCR assay to detect MRSA from clinical isolates or microbial DNA isolated from clinical samples in the hospital settings.
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Comparative study of the efficiency of silicon carbide, boron nitride and carbon nanotube to deliver cancerous drug, azacitidine: A DFT study. Comput Biol Med 2023; 154:106593. [PMID: 36746115 DOI: 10.1016/j.compbiomed.2023.106593] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/17/2022] [Accepted: 01/22/2023] [Indexed: 01/31/2023]
Abstract
Herein we have made a comparative study of the efficiency of three different nanotubes viz. Carbon nanotube (CNT), boron nitride nanotube (BNNT) and silicon carbide nanotube (SiCNT) to deliver the cancerous drug, Azacitidine (AZD). The atomistic description of the encapsulation process of AZD in these nanotubes has been analyzed by evaluating parameters like adsorption energy, electrostatic potential map, reduced density gradient (RDG). Higher adsorption energy of AZD with BNNT (-0.66eV), SiCNT (-0.92eV) compared to CNT (-0.56eV) confirms stronger binding affinity of the drug for the former than the later. Charge density and electrostatic potential map suggest that charge separation involving BNNT and CNT is more prominent than SiCNT. Evaluation of different thermodynamic parameters like Gibbs free energy, enthalpy change revealed that the overall encapsulation process is spontaneous and exothermic in nature and much favorable with BNNT and SiCNT. Stabilizing interactions of the drug with BNNT and SiCNT has been confirmed from RDG analysis. ADMP molecular dynamics simulation supports that the encapsulation process of the drug within the NT at room temperature. These results open up unlimited opportunities for the applications of these NTs as a drug delivery system in the field of nanomedicine.
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Prolonged Inflammation and Infectious Changes in the Corneal Epithelium Are Associated with Persistent Epithelial Defect (PED). Pathogens 2023; 12:pathogens12020261. [PMID: 36839533 PMCID: PMC9960897 DOI: 10.3390/pathogens12020261] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/07/2023] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
Purpose: Failure of rapid re-epithelialization within 10-14 days after corneal injury, even with standard supportive treatment, is referred to as persistent corneal epithelial (CE) defect (PED). Though an array of genes regulates reepithelization, their mechanisms are poorly understood. We sought to understand the network of genes driving the re-epithelialization in PED. Method: After obtaining informed consent, patients underwent an ophthalmic examination. Epithelial scrapes and tears samples of six PED patients and six individuals (control) undergoing photorefractive keratectomy (PRK) were collected. RNA isolation and quantification were performed using either the epithelial scrape taken from PED patients or from HCLE cells treated with control tears or tears of PED patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of a few important genes in CE homeostasis, inflammation, and cell-cell communication, viz., Kruppel-like factor 4 (KLF4), GPX4, IL6, TNFα, STING, IL8, desmoglein, and E-cadherin, among others. Their expressions were normalized with their respective housekeeping genes and fold changes were recorded. KLF4 localization and MMPs activity was carried out via immunofluorescence and zymography, respectively. Results: KLF4, a transcription factor important for CE homeostasis, was upregulated in tears-treated HCLE cells and downregulated in PED patients compared to the healthy PRK group. Cell-cell communication genes were also upregulated in tears-treated cells, whereas they were downregulated in the PED tissue group. Genes involved in proinflammation (IL6, 282-fold; TNFα, 43-fold; IL8, 4.2-fold) were highly upregulated in both conditions. MMP9 activity increased upon tears treatment. Conclusions: This study suggests that tears create an acute proinflammatory milieu driving the PED disease pathology, whereas the PED patients scrapes are an indicator of the chronic stage of the disease. Interferons, pro-inflammatory genes, and their pathways are involved in PED, which can be a potential target for inducing epithelialization of the cornea.
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Correlation of fine needle aspiration cytology and cell block study of category III, IV, and V (TBSRTC-2017) thyroid lesions with special reference to cytokeratin-19 immunohistochemical staining. INDIAN J PATHOL MICR 2022; 65:637-641. [PMID: 35900492 DOI: 10.4103/ijpm.ijpm_1037_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
CONTEXT Ascertaining the role of cytokeratin-19 (CK19) and its staining pattern helps to differentiate papillary carcinoma from other thyroid lesions. AIMS To correlate fine needle aspiration cytology (FNAC) and cell block study of equivocal cases (Category III, IV, and V) with the role of CK19 staining in it. SETTINGS AND DESIGN A hospital-based cross-sectional observational study was designed and conducted at North Bengal Medical College and Hospital, Shusrutnagar, Darjeeling. METHODS AND MATERIAL The FNAC performed and reported as per TBSRTC-2017.50 cases of Category III, IV, and V was selected for cell block study and CK19 staining followed by immunohistochemical scoring. RESULTS Out of 50 cases, 17 were follicular neoplasm, 21 papillary carcinoma, 6 lymphocytic thyroiditis, 1 Hürthle cell adenoma, 1 medullary carcinoma, 1 lymphoma, and 3 undifferentiated carcinomas. Among cases of papillary carcinoma, 10 showed 4+ positivity, 9 showed 3+ positivity, 2 showed focal 1+ and 2+ positivity. In the case of follicular neoplasm, 1 showed 3+ positivity, 3 cases had 1+ 2+ positivity, and 13 cases revealed negative staining. CONCLUSION Role of CK19 in distinguishing papillary carcinoma of thyroid from other lesions in cytologically diagnosed Category III, IV, and V (TBSRTC-2017) cases can be demonstrated.
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Repurposing of anti-lung cancer drugs as multi-target inhibitors of SARS-CoV-2 proteins: An insight from molecular docking and MD-simulation study. Microb Pathog 2022; 169:105615. [PMID: 35690231 PMCID: PMC9174081 DOI: 10.1016/j.micpath.2022.105615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 06/02/2022] [Accepted: 06/02/2022] [Indexed: 11/20/2022]
Abstract
Herein we have selected seventeen anti-lung cancer drugs to screen against Mpro, PLpro and spike glycoproteins of SARS-CoV-2to ascertain the potential therapeutic agent against COVID-19. ADMET profiling were employed to evaluate their pharmacokinetic properties. Molecular docking studies revealed that Capmatinib (CAP) showed highest binding affinity against the selected proteins of SARS-CoV-2. Molecular Dynamics (MD) simulation and the analysis of RMSD, RMSF, and binding energy confirmed the abrupt conformational changes of the proteins due to the presence of this drug. These findings provide an opportunity for doing advanced experimental research to evaluate the potential drug to combat COVID-19.
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Combinatorial topology and geometry of fracture networks. Phys Rev E 2022; 105:034801. [PMID: 35428072 DOI: 10.1103/physreve.105.034801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
A map is proposed from the space of planar surface fracture networks to a four-parameter mathematical space, summarizing the average topological connectivity and geometrical properties of a network idealized as a convex polygonal mesh. The four parameters are identified as the average number of nodes and edges, the angular defect with respect to regular polygons, and the isoperimetric ratio. The map serves as a low-dimensional signature of the fracture network and is visually presented as a pair of three-dimensional graphs. A systematic study is made of a wide collection of real crack networks for various materials, collected from different sources. To identify the characteristics of the real materials, several well-known mathematical models of convex polygonal networks are presented and worked out. These geometric models may correspond to different physical fracturing processes. The proposed map is shown to be discriminative, and the points corresponding to materials of similar properties are found to form closely spaced groups in the parameter space. Results for the real and simulated systems are compared in an attempt to identify crack networks of unknown materials.
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Green synthesis of antimicrobial silver nanoparticles using fruit extract of Glycosmis pentaphylla and its theoretical explanations. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2021.131361] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Frequency of glutathione S-Transferase M1, T1 and P1 genotypes and their combinations in northern West Bengal, India: Implications for disease association. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Publisher Correction: Graphene overcoats for ultra-high storage density magnetic media. Nat Commun 2021; 12:3437. [PMID: 34078909 PMCID: PMC8172630 DOI: 10.1038/s41467-021-23869-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Inhibitory efficacy of RNA virus drugs against SARS-CoV-2 proteins: An extensive study. J Mol Struct 2021; 1234:130152. [PMID: 33678903 PMCID: PMC7909904 DOI: 10.1016/j.molstruc.2021.130152] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/06/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023]
Abstract
Herein we have made a comprehensive analysis of inhibitory efficacy of 16 RNA virus drugs against RdRp, Mpro and PLpro proteins of SARS-CoV-2. Analysis of docked conformation revealed that Baloxavir marboxil (BMX) corresponds to the highest binding energy. Analysis of residue confirmed that BMX strongly interact with these three proteins involving H-bonding, ionic as well as hydrophobic interactions. Molecular dynamics simulation and analysis of parameters like RMSD, RMSF, binding energy confirmed noticeable conformational alternation with these proteins with makeable effect on RdRp. The potentially inhibitory action of BMX against these three proteins suggests the inhibition of overall transcription process of SARS-CoV-2. These observation along with the recently observed inhibitory action of BMX on influenza with clinically proven no side effects emphasizes to uncover the role of BMX by in-vitro and in-vivo analysis.
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Inhibitory efficiency of potential drugs against SARS-CoV-2 by blocking human angiotensin converting enzyme-2: Virtual screening and molecular dynamics study. Microb Pathog 2021; 152:104762. [PMID: 33524563 PMCID: PMC7845504 DOI: 10.1016/j.micpath.2021.104762] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/15/2020] [Accepted: 01/24/2021] [Indexed: 01/20/2023]
Abstract
Till date millions of people are infected by SARS-CoV-2 throughout the world, while no potential therapeutics or vaccines are available to combat this deadly virus. Blocking of human angiotensin-converting enzyme 2 (ACE-2) receptor, the binding site of SARS-CoV-2 spike protein, an effective strategy to discover a drug for COVID-19. Herein we have selected 24 anti-bacterial and anti-viral drugs and made a comprehensive analysis by screened them virtually against ACE-2 receptor to find the best blocker by molecular docking and molecular dynamics studies. Analysis of results revealed that, Cefpiramide (CPM) showed the highest binding affinity of −9.1 kcal/mol. Furthermore, MD study for 10 ns and evaluation of parameters like RMSD, RMSF, radius of gyration, solvent accessible surface area analysis confirmed that CPM effectively binds and blocks ACE-2 receptor efficiently.
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Biogenic silver nanoparticle synthesis and stabilization for apoptotic activity; insights from experimental and theoretical studies. CHEMICAL PAPERS 2020. [DOI: 10.1007/s11696-020-01216-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chitosan encapsulated water-soluble silver bionanocomposite for size-dependent antibacterial activity. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.nanoso.2019.100393] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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High resolution spectroscopy on Te 2: New lines for reference. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 208:109-113. [PMID: 30300860 DOI: 10.1016/j.saa.2018.09.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/25/2018] [Accepted: 09/30/2018] [Indexed: 06/08/2023]
Abstract
Ro-vibrational spectra of different electronic states of molecules are often used as absolute wavelength or frequency standards. These standards are also used to mitigate any slow drift of laser frequency during an experiment. In the precision experiment, the two most commonly used molecular standards are iodine and tellurium, both are homo-nuclear diatomic molecules. The former is mostly used as standard for the long wavelength (600-900 nm) region, while the tellurium spectrum is widely used in short wavelength (400-550 nm) including near ultraviolet. A comprehensive data on tellurium spectra can be obtained from the tellurium atlas [1]. However near the 455 nm range where a number of important atomic resonance line, the atlas provides no significant data. We have performed high resolution modulation transfer spectroscopy (MTS) on tellurium molecule in a hot cell in the region close to 455 nm wavelength thereby obtained more than 100 new spectral lines which were not observed before. The linewidth of each of these peaks is about a few tens of MHz, making them suitable for laser frequency locking.
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Performance of three delignifying pretreatments on hardwoods: hydrolysis yields, comprehensive mass balances, and lignin properties. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:213. [PMID: 31516552 PMCID: PMC6732840 DOI: 10.1186/s13068-019-1546-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/23/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND In this work, three pretreatments under investigation at the DOE Bioenergy Research Centers (BRCs) were subjected to a side-by-side comparison to assess their performance on model bioenergy hardwoods (a eucalyptus and a hybrid poplar). These include co-solvent-enhanced lignocellulosic fractionation (CELF), pretreatment with an ionic liquid using potentially biomass-derived components (cholinium lysinate or [Ch][Lys]), and two-stage Cu-catalyzed alkaline hydrogen peroxide pretreatment (Cu-AHP). For each of the feedstocks, the pretreatments were assessed for their impact on lignin and xylan solubilization and enzymatic hydrolysis yields as a function of enzyme loading. Lignins recovered from the pretreatments were characterized for polysaccharide content, molar mass distributions, β-aryl ether content, and response to depolymerization by thioacidolysis. RESULTS All three pretreatments resulted in significant solubilization of lignin and xylan, with the CELF pretreatment solubilizing the majority of both biopolymer categories. Enzymatic hydrolysis yields were shown to exhibit a strong, positive correlation with the lignin solubilized for the low enzyme loadings. The pretreatment-derived solubles in the [Ch][Lys]-pretreated biomass were presumed to contribute to inhibition of enzymatic hydrolysis in the eucalyptus as a substantial fraction of the pretreatment liquor was carried forward into hydrolysis for this pretreatment. The pretreatment-solubilized lignins exhibited significant differences in polysaccharide content, molar mass distributions, aromatic monomer yield by thioacidolysis, and β-aryl ether content. Key trends include a substantially higher polysaccharide content in the lignins recovered from the [Ch][Lys] pretreatment and high β-aryl ether contents and aromatic monomer yields from the Cu-AHP pretreatment. For all lignins, the 13C NMR-determined β-aryl ether content was shown to be correlated with the monomer yield with a second-order functionality. CONCLUSIONS Overall, it was demonstrated that the three pretreatments highlighted in this study demonstrated uniquely different functionalities in reducing biomass recalcitrance and achieving higher enzymatic hydrolysis yields for the hybrid poplar while yielding a lignin-rich stream that may be suitable for valorization. Furthermore, modification of lignin during pretreatment, particularly cleavage of β-aryl ether bonds, is shown to be detrimental to subsequent depolymerization.
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Efficient dehydration and recovery of ionic liquid after lignocellulosic processing using pervaporation. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:154. [PMID: 28638441 PMCID: PMC5472906 DOI: 10.1186/s13068-017-0842-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
BACKGROUND Biomass pretreatment using certain ionic liquids (ILs) is very efficient, generally producing a substrate that is amenable to saccharification with fermentable sugar yields approaching theoretical limits. Although promising, several challenges must be addressed before an IL pretreatment technology can become commercially viable. One of the most significant challenges is the affordable and scalable recovery and recycle of the IL itself. Pervaporation (PV) is a highly selective and scalable membrane separation process for quantitatively recovering volatile solutes or solvents directly from non-volatile solvents that could prove more versatile for IL dehydration. RESULTS We evaluated a commercially available PV system for IL dehydration and recycling as part of an integrated IL pretreatment process using 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) that has been proven to be very effective as a biomass pretreatment solvent. Separation factors as high as 1500 were observed. We demonstrate that >99.9 wt% [C2C1Im][OAc] can be recovered from aqueous solution (≤20 wt% IL) and recycled five times. A preliminary technoeconomic analysis validated the promising role of PV in improving overall biorefinery process economics, especially in the case where other IL recovery technologies might lead to significant losses. CONCLUSIONS These findings establish the foundation for further development of PV as an effective method of recovering and recycling ILs using a commercially viable process technology.
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Rhodosporidium toruloides: a new platform organism for conversion of lignocellulose into terpene biofuels and bioproducts. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:241. [PMID: 29075325 PMCID: PMC5651578 DOI: 10.1186/s13068-017-0927-5] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/10/2017] [Indexed: 05/22/2023]
Abstract
BACKGROUND Economical conversion of lignocellulosic biomass into biofuels and bioproducts is central to the establishment of a robust bioeconomy. This requires a conversion host that is able to both efficiently assimilate the major lignocellulose-derived carbon sources and divert their metabolites toward specific bioproducts. RESULTS In this study, the carotenogenic yeast Rhodosporidium toruloides was examined for its ability to convert lignocellulose into two non-native sesquiterpenes with biofuel (bisabolene) and pharmaceutical (amorphadiene) applications. We found that R. toruloides can efficiently convert a mixture of glucose and xylose from hydrolyzed lignocellulose into these bioproducts, and unlike many conventional production hosts, its growth and productivity were enhanced in lignocellulosic hydrolysates relative to purified substrates. This organism was demonstrated to have superior growth in corn stover hydrolysates prepared by two different pretreatment methods, one using a novel biocompatible ionic liquid (IL) choline α-ketoglutarate, which produced 261 mg/L of bisabolene at bench scale, and the other using an alkaline pretreatment, which produced 680 mg/L of bisabolene in a high-gravity fed-batch bioreactor. Interestingly, R. toruloides was also observed to assimilate p-coumaric acid liberated from acylated grass lignin in the IL hydrolysate, a finding we verified with purified substrates. R. toruloides was also able to consume several additional compounds with aromatic motifs similar to lignin monomers, suggesting that this organism may have the metabolic potential to convert depolymerized lignin streams alongside lignocellulosic sugars. CONCLUSIONS This study highlights the natural compatibility of R. toruloides with bioprocess conditions relevant to lignocellulosic biorefineries and demonstrates its ability to produce non-native terpenes.
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Impact of lignin polymer backbone esters on ionic liquid pretreatment of poplar. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:101. [PMID: 28439294 PMCID: PMC5399332 DOI: 10.1186/s13068-017-0784-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/11/2017] [Indexed: 05/18/2023]
Abstract
BACKGROUND Biomass pretreatment remains an essential step in lignocellulosic biofuel production, largely to facilitate the efficient removal of lignin and increase enzyme accessibility to the polysaccharides. In recent years, there have been significant efforts in planta to reduce lignin content or modify its composition to overcome the inherent recalcitrance that it imposes on lignocellulosic biomass during processing. Here, transgenic poplar lines in which monolignol ferulate conjugates were synthesized during cell wall development to introduce, during lignification, readily cleavable ester linkages into the lignin polymer backbone (i.e., "zip lignin"), along with wild-type (WT) controls, were pretreated with different ionic liquids (ILs). RESULTS The strategic introduction of ester bonds into the lignin backbone resulted in increased pretreatment efficiency and released more carbohydrates with lower energy input. After pretreatment with any of three different ILs, and after limited saccharification, the transgenic poplars, especially those with relatively higher amounts of incorporated monolignol ferulate conjugates, yielded up to 23% higher sugar levels compared to WT plants. CONCLUSION Our findings clearly demonstrate that the introduction of ester linkages into the lignin polymer backbone decreases biomass recalcitrance in poplar has the potential to reduce the energy and/or amount of IL required for effective pretreatment, and could enable the development of an economically viable and sustainable biorefinery process.
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Activation of lignocellulosic biomass for higher sugar yields using aqueous ionic liquid at low severity process conditions. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:160. [PMID: 27486479 PMCID: PMC4969646 DOI: 10.1186/s13068-016-0561-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/12/2016] [Indexed: 05/02/2023]
Abstract
BACKGROUND Concerns around greenhouse gas emissions necessitate the development of sustainable processes for the production of chemicals, materials, and fuels from alternative renewable sources. The lignocellulosic plant cell walls are one of the most abundant sources of carbon for renewable bioenergy production. Certain ionic liquids (ILs) are very effective at disrupting the plant cell walls of lignocellulose, and generate a substrate that is effectively hydrolyzed into fermentable sugars. Conventional ILs are relatively expensive in terms of purchase price, and the most effective imidazolium-based ILs also require energy intensive processing conditions (>140 °C, 3 h) to release >90 % fermentable sugar yields after saccharification. RESULTS We have developed a highly effective pretreatment technology utilizing the relatively inexpensive IL comprised tetrabutylammonium [TBA](+) and hydroxide [OH](-) ions that generate high glucose yields (~95 %) after pretreatment at very mild processing conditions (50 °C). The efficiency of [TBA][OH] pretreatment of lignocellulose was further studied by analyzing chemical composition, powder X-ray diffraction for cellulose structure, NMR and SEC for lignin dissolution/depolymerization, and glycome profiling for cell wall modifications. Glycome profiling experiments and computational results indicate that removal of the noncellulosic polysaccharides occurs due to the ionic mobility of [TBA][OH] and is the key factor in determining pretreatment efficiency. Process modeling and energy demand analysis suggests that this [TBA][OH] pretreatment could potentially reduce the energy required in the pretreatment unit operation by more than 75 %. CONCLUSIONS By leveraging the benefits of ILs that are effective at very mild processing conditions, such as [TBA][OH], lignocellulosic biomass can be pretreated at similar efficiency as top performing conventional ILs, such as 1-ethyl-3-methylimidazolium acetate [C2C1Im][OAc], but at much lower temperatures, and with less than half the IL normally required to be effective. [TBA][OH] IL is more reactive in terms of ionic mobility which extends removal of lignin and noncellulosic components of biomass at the lower temperature pretreatment. This approach to biomass pretreatment at lower temperatures could be transformative in the affordability and energy efficiency of lignocellulosic biorefineries.
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Assessment of anti-inflammatory and anti-arthritic properties of Acmella uliginosa (Sw.) Cass. based on experiments in arthritic rat models and qualitative gas chromatography-mass spectrometry analyses. JOURNAL OF COMPLEMENTARY MEDICINE RESEARCH 2016; 5:257-62. [PMID: 27366352 PMCID: PMC4927131 DOI: 10.5455/jice.20160521010145] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/03/2016] [Indexed: 11/29/2022]
Abstract
Aim: The principle objective of the study was to explore the anti-arthritic properties of Acmella uliginosa (AU) (Sw.) Cass. flower in a rat model and to identify potential anti-inflammatory compounds derived from flower extracts. The synergistic role played by a combination of AU flower and Aloe vera (AV) gel crude extracts was also investigated. Materials and Methods: Male Wistar rats induced with Freund’s complete adjuvant (FCA) were used as a disease model of arthritic paw swelling. There were three experimental and two control groups, each consisting of five rats. Paw circumference and serum biochemical parameters were evaluated to investigate the role of the flower extracts in disease amelioration through a feeding schedule spanning 21 days. Gas chromatography/mass spectrometry (GC/MS) analyses were performed to search for the presence of anti-inflammatory compounds in the ethanolic and n-hexane solvent extracts of the flower. Results: As a visual cue to the experimental outcomes, FCA-induced paw swelling decreased to the normal level; and hemoglobin, serum protein, and albumin levels were significantly increased in the treated animals. The creatinine level was estimated to be normal in the experimental rats after the treatment. The combination of AU and AV showed the best recovery potential in all the studied parameters, confirming the synergistic efficacy of the herbal formulation. GC/MS analyses revealed the presence of at least 5 anti-inflammatory compounds including 9-octadecenoic acid (Z)-, phenylmethyl ester, astaxanthin, à-N-Normethadol, fenretinide that have reported anti-inflammatory/anti-arthritic properties. Conclusion: Our findings indicated that the crude flower homogenate of AU contains potential anti-inflammatory compounds which could be used as an anti-inflammatory/anti-arthritic medication.
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Conjugated foldamers with unusually high space-charge-limited current hole mobilities. ACS APPLIED MATERIALS & INTERFACES 2015; 7:9372-9384. [PMID: 25915005 DOI: 10.1021/acsami.5b01676] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Charge carrier mobility and its optimization play a critical role in the development of cutting-edge organic electronic and optoelectronic devices. Even though space-charge-limited current (SCLC) hole mobilities as high as 1.4 cm(2) V(-1) s(-1) have been reported for microscopically sized highly ordered liquid-crystalline conjugated small molecules, the SCLC hole mobility of device-sized thin films of conjugated polymers is still much lower, ranging from 10(-6) to 10(-3) cm(2) V(-1) s(-1). Herein, we report the synthesis, characterizations, and thin-film SCLC mobility of three discotic conjugated polymers, INDT-TT, INDT-BT, and INDT-NDT. Optical studies indicate that polymer INDT-NDT adopts a folded conformation in solutions of good or poor solvents, whereas polymer INDT-TT stays as random monomeric chains in good solvents and interchain aggregates in poor solvents. INDT-BT polymer chains, however, stay as foldamers in dilute solutions of good solvents but interchain aggregates in concentrated solutions or poor solvents. Circular dichroism spectroscopy provides clear evidence for the helical folding of INDT-NDT in solutions. Thin films spin-coated from 1,2-dichlorobenzene solutions of the polymers show SCLC hole mobility of 2.20 × 10(-6), 8.79 × 10(-5), and 2.77 × 10(-2) cm(2) V(-1) s(-1) for INDT-TT, INDT-BT, and INDT-NDT, respectively. HRTEM and powder XRD measurements show that INDT-NDT pristine thin films contain nanocrystalline domains, whereas the INDT-TT and INDT-BT films are amorphous. Thin films of INDT-NDT:PC71BM blends show increased crystallinity and further improved SCLC hole mobility up to 1.29 × 10(-1) cm(2) V(-1) s(-1), one of the highest SCLC mobility values ever recorded on solution-processed organic semiconducting thin films. The persistent folding conformation of INDT-NDT is believed to be responsible for the high crystallinity of its thin films and its high SCLC mobilities.
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Luminescent Polythiophene-Based Main-Chain Polyoxometalate-Containing Conjugated Polymers with Improved Solar-Cell Performance. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201402839] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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CHAPTER 3. Ionic Liquid Pretreatment of Lignocellulosic Biomass for Biofuels and Chemicals. GREEN CHEMISTRY SERIES 2015. [DOI: 10.1039/9781782622598-00065] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Ramp dynamics of phonons in an ion trap: entanglement generation and cooling. PHYSICAL REVIEW LETTERS 2013; 111:170406. [PMID: 24206467 DOI: 10.1103/physrevlett.111.170406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Indexed: 06/02/2023]
Abstract
We show that the ramp dynamics of phonons in a one-dimensional ion trap can be used for both generating multiparticle entangled states and motional state cooling of a string of trapped ions. We study such ramp dynamics using an effective Bose-Hubbard model which describes these phonons at low energies and show that specific protocols, involving site-specific dynamical tuning of the on-site potential of the model, can be used to generate entangled states and to achieve motional state cooling without involving electronic states of the ions. We compare and contrast our schemes for these to the earlier suggested ones and discuss specific experiments to realize the suggested protocols.
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Imide-functionalized naphthodithiophene based donor-acceptor conjugated polymers for solar cells. ACTA ACUST UNITED AC 2013. [DOI: 10.1002/pola.26799] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Synthesis, Characterizations, and Morphological Studies of Polyoxometalate-Containing Rod-Coil Diblock Copolymers. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201201127] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Synthesis and optical properties of perylene diimide derivatives with triphenylene-based dendrons linked at the bay positions through a conjugated ethynyl linkage. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.02.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Synthesis and Optical Properties of Triphenylene-Based Dendritic Donor Perylene Diimide Acceptor Systems. J Phys Chem A 2011; 115:1579-92. [DOI: 10.1021/jp1085334] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Development, characterization and in vitro assessement of stearylamine-based lipid nanoparticles of paclitaxel. DIE PHARMAZIE 2011; 66:171-177. [PMID: 21553646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The objective of the study was to design and evaluate a solid lipid nanoparticle (SLN) drug delivery system for delivery of paclitaxel. Components of the SLN were lipid (stearylamine) and surfactants (Pluronic F68 and Soya lecithin). The paclitaxel loaded nanoparticles were prepared by a modified solvent injection method. Experiments were carried out with excipients, where surfactants, lipid and drug molar ratios were varied to optimize the formulation characteristics. The in vitro drug release profile from the nanoparticles followed a diffusion controlled mechanism. The modified solvent injection method ensured high entrapment efficiency (approximately 75%), produced smaller, stable nanoparticles with a narrow size distribution and proved to be a reproducible and fast production method. The present study describes the feasibility and suitability of stearylamine based SLN produced using a mixture of surfactants to develop a clinically useful system with targeting potential for poorly soluble antineoplastic drugs.
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Conjugated polymers with large effective Stokes shift: benzobisdioxole-based poly(phenylene ethynylene)s. J Am Chem Soc 2010; 131:17321-7. [PMID: 19891484 DOI: 10.1021/ja9068134] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phenyleneethynylene-based conjugated copolymers using benzo[1,2-d:4,5-d']bis[1,3]dioxole (BDO) in the repeating unit are reported. The electronic structure of the BDO unit imparts a localized HOMO topology while the LUMO is delocalized over the polymer backbone, so that the lowest optical absorption band of the polymer has considerable intramolecular charge transfer character. This contrasts with published donor-acceptor polymers with localized LUMO and delocalized HOMO. The very large Stokes shifts of the monomers, which are due to the small oscillator strength of the lowest optical transition, are largely retained in the polymers as a result of covalently constrained dihedral angles in the substituents (not the backbone), as predicted/explained by calculations.
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Characterization and in vitro assessment of paclitaxel loaded lipid nanoparticles formulated using modified solvent injection technique. DIE PHARMAZIE 2009; 64:301-310. [PMID: 19530440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This study investigates the design and characterization of solid lipid nanoparticles (SLNs) containing paclitaxel fabricated by a modified solvent injection technique using stearic acid as lipid and stabilized by a mixture of surfactants, for future evaluation of this colloidal carrier system for the oral delivery of paclitaxel, devoid of the side effects of Cremophor EL. SLN formulations of paclitaxel stabilized by mixture of surfactants i.e. lecithin/poloxamer 188 were developed with smaller size and narrow size distribution. The paclitaxel-loaded SLNs exhibited spherical shape with smooth surface as analyzed by transmission electron microscopy (TEM). The average particle size obtained through this method was found to be approximately 113 nm. The zeta potential was between -32 and -39 mV with poloxamer 188. Encapsulation efficiencies of about 72.18 +/- 3.7 and 89.0 +/- 2.4% were achieved using 0.05 and 0.25 mmol of paclitaxel, respectively. Paclitaxel showed a sustained in vitro release profile and was found to follow Higuchi kinetic equations. In vitro cytotoxicity assay confirmed that paclitxel entrapped in SLNs showed higher cytotoxicity against cultured hepatocelluler carcinoma cells than paclitaxel alone. The modified solvent injection technique used in this research proved to be a simple, easily available and effective method to produce SLNs and could be used for controlled delivery of different lipophilic drugs for cancer chemotherapy.
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Desiccation of a clay film: cracking versus peeling. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2008; 27:391-395. [PMID: 19067005 DOI: 10.1140/epje/i2008-10401-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Revised: 10/21/2008] [Accepted: 11/11/2008] [Indexed: 05/27/2023]
Abstract
We report a simulation study on competition between cracking and peeling, in a layer of clay on desiccation and how this is affected by the rate of drying, as well as the roughness of the substrate. The system is based on a simple 2-dimensional spring model. A vertical section through the layer with finite thickness is represented by a rectangular array of nodes connected by linear springs on a square lattice. The effect of reduction of the natural length of the springs, which mimics the drying is studied. Varying the strength of adhesion between sample and substrate and the rate of penetration of the drying front produces an interesting phase diagram, showing cross-over from peeling to cracking behavior. Changes in the number and width of cracks on varying the layer thickness is observed to reproduce experimental reports.
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Adhesion and fingering in the lifting Hele-Shaw cell: role of the substrate. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2008; 25:267-275. [PMID: 18385932 DOI: 10.1140/epje/i2007-10289-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Accepted: 02/06/2008] [Indexed: 05/26/2023]
Abstract
The lifting Hele-Shaw cell (LHSC) is used to study adhesion as well as viscous fingering. In the present paper we report a series of observations of development of the interface for different viscous fluids, both Newtonian and non-Newtonian, in a LHSC operated at a constant lifting force. Glass and perspex are used as the plates in two different sets of experiments. The objectives are 1) to measure the time required to separate the plates as a function of the lifting force and 2) to note the force above which viscous fingering appears. We find that for the Newtonian fluids, the plate separation time follows a universal power law with the lifting force, irrespective of fluid and substrate. The non-Newtonian fluids too, with proper scaling obey the same power law. The appearance of fingering, however, depends on the properties of the fluid as well as the substrate. We suggest a modified form of the capillary number which controls the onset of fingering; this new quantity, termed the "fingering parameter" involves the dielectric constants of the substrate and fluid in addition to the viscosity and surface tension.
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Transition-metal-free synthesis of poly(phenylene ethynylene)s with alternating aryl-perfluoroaryl units. J Am Chem Soc 2007; 130:452-3. [PMID: 18088129 DOI: 10.1021/ja710564b] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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A novel cellulase free alkaliphilic xylanase from alkali tolerant Penicillium citrinum: production, purification and characterization. Lett Appl Microbiol 2007; 44:206-11. [PMID: 17257262 DOI: 10.1111/j.1472-765x.2006.02042.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIMS The enzymatic hydrolysis of xylan has potential economic and environment-friendly applications. Therefore, attention is focused here on the discovery of new extremophilic xylanase in order to meet the requirements of industry. METHODS AND RESULTS An extracellular xylanase was purified from the culture filtrate of P. citrinum grown on wheat bran bed in solid substrate fermentation. Single step purification was achieved using hydrophobic interaction chromatography. The purified enzyme showed a single band on SDS-PAGE with an apparent molecular weight of c. 25 kDa and pI of 3.6. Stimulation of the activity by beta mercaptoethanol, dithiotheritol (DTT) and cysteine was observed. Moderately thermostable xylanase showed optimum activity at 50 degrees C at pH 8.5. CONCLUSION Xylanase purified from P. citrinum was alkaliphilic and moderately thermostable in nature. SIGNIFICANCE AND IMPACT OF THE STUDY The present work reports for the first time the purification and characterization of a novel endoglucanase free alkaliphilic xylanase from the alkali tolerant fungus Penicillium citrinum. The alkaliphilicity and moderate thermostability of this xylanase may have potential implications in paper and pulp industries.
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Body Mass Index in Central India: Inter District Variation. Journal of Biological and Clinical Anthropology 2006. [DOI: 10.1127/anthranz/64/2006/447] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Body mass index in Central India: inter district variation. ANTHROPOLOGISCHER ANZEIGER; BERICHT UBER DIE BIOLOGISCH-ANTHROPOLOGISCHE LITERATUR 2006; 64:447-61. [PMID: 17240962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Basic causes of poor state of nutrition and infections in developing countries are poverty, low level of hygienic conditions and little access to preventive and health care. Central India is known for its high rate of population growth and mortality, which persisted over time along with a low level of social, economic and infrastructure development. In the present study the body mass index (BMI) of 31 populations residing in 38 districts of Central India (comprising the States of Madhya Pradesh and Chhattisgarh) is assessed. Anthropometric data collected by the Anthropological Survey of India were utilized in this context. The mean body mass index values of the populations of total backward and non-backward districts are found to be lower than that of well-to-do individuals of India (Bharati 1989, Khongsdier 1997, Reddy 1998), but it is not as low as that found among the South Indian populations (Ferro-Luzzi et al. 1992). In the present investigation, it is also found that the majority of the backward districts fall in the category of different grade of chronic energy deficiency (CED), while in the non-backward districts a considerably less number of districts follows this trend. A better level of the nutritional status among the populations of the non-backward districts corroborates the findings of the Ministry of Health and Family Welfare (NFHS 1992). It reveals that the apparently healthy individuals with CED grade I in the present study may be thin but physically active and healthy. The present study, however, narrates further intensive investigations in these populations, because the BMI as a measure of the CED should incorporate the aspects like morbidity and health status of a population.
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Forceshoes: Portable ground reaction sensors for biomechanical analysis in the work place. J Biomech 2006. [DOI: 10.1016/s0021-9290(06)85209-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
The purpose of this study was to examine (a) the incidence of leftward bias for paired organs (hand, foot, eye, and ear) in India (n = 418) and Japan (n = 697), and (b) the incidence of accident amongst individuals with leftward, rightward, and no bias across countries. The impetus for the study was obtained from a speculation that individuals with leftward bias commit more accidents than their counterparts. Data were collected with the help of a questionnaire on side bias, along with a check-list on accidents (included in the questionnaire). Results showed that participants from these two countries did not differ in terms of leftwardness for any of these forms of side bias. Left-handers were found to commit more accidents in India but not in Japan. Reanalysis of data in terms of left-, mixed-, and right-handedness indicated that mixed handers committed more accidents than extreme (left- + right-) handers in Japan but not in India.
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Initiation and regulation of the response to brain micro-tumor. J Neuroimmunol 1998. [DOI: 10.1016/s0165-5728(98)91782-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Leiomyomatosis peritonealis disseminata. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1995; 93:19-20. [PMID: 7759901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Abstract
Complete eventration of the diaphragm and pulmonary aplasia, though rare anomalies, should be considered in new-borns with respiratory distress. Such anomalous conditions occurring either alone or in combination elude diagnosis and pose problems for management. CT is a very effective, non invasive means of diagnosis which in the past depended largely on invasive procedures such as bronchography, angiography and thoracotomy.
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Abstract
Strangulated diaphragmatic hernia is a surgical emergency which on occasions can be a diagnostic dilemma. We report of a 2-year-old-male child with strangulated diaphragmatic hernia in whom a correct preoperative diagnosis was made with progression of illness. CT depicted a curvilinear fat stripe in a fluid filled hemithorax.
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Abstract
Genituorinary tract is a common site of origin of rhabdomyosarcomas. Not very many cases of urinary bladder rhabdomyosarcomas have been reported in the computed tomography literature. We present computed tomography appearances which were virtually classical to diagnose botryoid variety of embryonal rhabdomyosarcoma in a two year old male child.
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Alport's syndrome--study of a family. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1985; 33:746. [PMID: 4093391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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