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Find video protocols related to scientific articles indexed in Pubmed.
Improved physicochemical characteristics of artemisinin using succinic acid.
Acta Pol Pharm
PUBLISHED: 10-01-2014
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Artemisinin (ARMN) is a potent antimalarial drug, which is effective against multidrug resistant strains of Plasmodium falciparum and produces rapid recovery even in patients with cerebral malaria. Being poorly soluble in water, artemisinin is incompletely absorbed after oral intake due to poor dissolution characteristics in the intestinal fluids. To enhance these properties, solid dispersions of artemisinin with succinic acid (SUC) were prepared using drug-carrier ratios 1 : 1, 1 : 4, 1 : 6, 1 : 8 and 1 : 10 by solvent evaporation and freeze drying methods. These solid dispersions were characterized by differential scanning calorimetery (DSC), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction patterns (XRD), phase solubility and dissolution kinetics evaluated by applying zero order, first order, Higuchi, and Korsmeyer-Peppas models. Physical mixtures produced significantly higher aqueous solubility and rate of dissolution as compared to artemisinin alone. The dissolution profiles of all formulations followed Higuchi model and exhibited diffusion-controlled release of drug. Solvent evaporation method (SLVPs) exhibited improved solubility and freeze dried solid dispersions (FDSDs) produced highest solubility but stability constant was opposite. ARMN and SUC both were found completely crystalline as shown by their XRD patterns. Physical mixtures (PMs) showed reduced intensity in their XRD patterns while solid dispersions by SLVPs exhibited twice reduced intensity and much displaced angles, whereas FDSDs showed synergistic effects in some of ARMN and SUC peaks. DSC thermograms of FDSDs at drug-carrier ratios 1 : 1-1 : 4 showed lower melting temperature and enthalpy change (deltaH) values than respective SLVPs, whereas at higher ratios, a reverse was true. SLVPs showed displaced methyl stretching bands at lower drug-carrier ratios and exhibited O-H stretching characteristic bands of SUC at higher drug-carrier ratios. In addition, carbonyl group and C-O stretching vibrations characteristic of SUC (1307 cm(-1)) appeared prominently compared to PMs, whereas C-O stretching characteristic bands of ARMN disappeared at higher ratios. FDSDs exhibited distinct nature of bonding compared to respective SLVPs and PMs.
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Predictors of poor outcome of decompressive craniectomy in pediatric patients with severe traumatic brain injury: a retrospective single center study from Pakistan.
Childs Nerv Syst
PUBLISHED: 09-25-2014
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This study aimed to determine the risk factors associated with poor outcome of decompressive craniectomy (DC) for severe traumatic brain injury (TBI) in pediatric patients.
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SeqCompress: An algorithm for biological sequence compression.
Genomics
PUBLISHED: 08-27-2014
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The growth of Next Generation Sequencing technologies presents significant research challenges, specifically to design bioinformatics tools that handle massive amount of data efficiently. Biological sequence data storage cost has become a noticeable proportion of total cost in the generation and analysis. Particularly increase in DNA sequencing rate is significantly outstripping the rate of increase in disk storage capacity, which may go beyond the limit of storage capacity. It is essential to develop algorithms that handle large data sets via better memory management. This article presents a DNA sequence compression algorithm SeqCompress that copes with the space complexity of biological sequences. The algorithm is based on lossless data compression and uses statistical model as well as arithmetic coding to compress DNA sequences. The proposed algorithm is compared with recent specialized compression tools for biological sequences. Experimental results show that proposed algorithm has better compression gain as compared to other existing algorithms.
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Localization and characterization of ferritin in Demospongiae: a possible role on spiculogenesis.
Mar Drugs
PUBLISHED: 08-22-2014
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Iron, as inorganic ion or as oxide, is widely used by biological systems in a myriad of biological functions (e.g., enzymatic, gene activation and/or regulation). In particular, marine organisms containing silica structures--diatoms and sponges--grow preferentially in the presence of iron. Using primary sponge cell culture from S. domuncula-primmorphs--as an in vitro model to study the Demospongiae spiculogenesis, we found the presence of agglomerates 50 nm in diameter exclusively inside sponge specialized cells called sclerocytes. A clear phase/material separation is observed between the agglomerates and the initial stages of intracellular spicule formation. STEM-HRTEM-EDX analysis of the agglomerates (30-100 nm) showed that they are composed of pseudohexagonal nanoparticles between 5 and 15 nm in size, displaying lattice parameters corresponding to hematite (Fe2O3) and mixed iron oxide phases typically attributed to ferritin. Further analysis, using western blotting, inductively coupled plasma mass spectrometry (ICP-MS), sequence alignment analysis, immunostaining and magnetic resonance imaging (MRI), of mature spicule filaments confirm the presence of ferritin within these organic structures. We suggest that S. domuncula can be classified as a dual biomineralizating organism, i.e., within the same cellular structure two distinct biomineralizing processes can occur as a result of the same cellular/metabolic function, spiculogenesis.
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Synthesis of novel ZnV?O? hierarchical nanospheres and their applications as electrochemical supercapacitor and hydrogen storage material.
ACS Appl Mater Interfaces
PUBLISHED: 08-11-2014
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Hierarchical nanostructures (Hs) have recently garnered enormous attention due to their remarkable performances in catalysis, electronic devices, energy storage and conversion. Considering the advantage of hierarchical nanostructures, we have formulated a facile and template free method to synthesize novel hierarchical nanospheres (NHNs) of ZnV2O4. Both zinc and vanadium are earth abundant, relatively economical and can offer several oxidation states, which can render a broad range of redox reactions favorable for electrochemical energy storage applications. Keeping these points in mind, we investigated for the first time the electrochemical supercapacitor performance of NHNs. The electrochemical measurements were performed in 2 M KOH solution. The measured specific capacitance of ZnV2O4 electrode is 360 F/g at 1 A/g with good stability and retention capacity of 89% after 1000 cycles. Moreover, the hydrogen storage properties of NHNs were measured at 473, 573, and 623 K with an absorption of 1.76, 2.03, and 2.49 wt %. respectively. These studies pave the way to consider ZnV2O4 as prospective material for energy storage applications.
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Ferrocene-based guanidine derivatives: in vitro antimicrobial, DNA binding and docking supported urease inhibition studies.
Eur J Med Chem
PUBLISHED: 08-01-2014
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Some novel ferrocenyl guanidines 1-8 were synthesized and characterized by different spectroscopic methods, elemental analysis and single crystal X-rays diffraction techniques. The crystallographic studies revealed that the existence of the strong non-bonding interactions facilitate these molecules to interact with biological macro-molecules like DNA that described to inherit good biological activities. The DNA interaction studies carried out by cyclic voltammetry (CV) and UV-visible spectroscopy are in close agreement with the binding constants (K) (0.79-5.4) × 10(5) (CV) and (0.72-5.1) × 10(5) (UV-vis). The shift in peak potential, current and absorption maxima of the studied ferrocenyl guanidines in the presence of DNA revealed that CV coupled with UV-vis spectroscopy could provide an opportune to characterize metal-based compounds-DNA interaction mechanism, a prerequisite for the design of new anticancer agents and understanding the molecular basis of their action. The compounds 1-8 have been screened for their antibacterial, antifungal and urease inhibition potency. A concurrent in silico study has also been applied on ferrocene moiety impregnated guanidines 1-8 to identify most active compounds having for inhibiting the activity of urease (pdb id 3LA4). Most of the compounds were found as potent inhibitors of urease and the compound 1 was found to be the most active with an IC50 of 16.83 ± 0.03 ?M. The docking scores are in close agreement with the in vitro obtained IC50 values of inhibitors 1-8.
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Recent developments in therapeutic protein expression technologies in plants.
Biotechnol. Lett.
PUBLISHED: 07-31-2014
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Infectious diseases and cancers are some of the commonest causes of deaths throughout the world. The previous two decades have witnessed a combined endeavor across various biological sciences to address this issue in novel ways. The advent of recombinant DNA technologies has provided the tools for producing recombinant proteins that can be used as therapeutic agents. A number of expression systems have been developed for the production of pharmaceutical products. Recently, advances have been made using plants as bioreactors to produce therapeutic proteins directed against infectious diseases and cancers. This review highlights the recent progress in therapeutic protein expression in plants (stable and transient), the factors affecting heterologous protein expression, vector systems and recent developments in existing technologies and steps towards the industrial production of plant-made vaccines, antibodies, and biopharmaceuticals.
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Fabrication of single cylindrical Au-coated nanopores with non-homogeneous fixed charge distribution exhibiting high current rectifications.
ACS Appl Mater Interfaces
PUBLISHED: 07-30-2014
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We designed and characterized a cylindrical nanopore that exhibits high electrochemical current rectification ratios at low and intermediate electrolyte concentrations. For this purpose, the track-etched single cylindrical nanopore in polymer membrane was coated with a gold (Au) layer via electroless plating technique. Then, a non-homogeneous fixed charge distribution inside the Au-coated nanopore was obtained by incorporating thiol-terminated uncharged poly(N-isopropylacrylamide) chains in series to poly(4-vinylpyridine) chains, which were positively charged at acidic pH values. The functionalization reaction was checked by measuring the current-voltage curves prior to and after the chemisorption of polymer chains. The experimental nanopore characterization included the effects of temperature, adsorption of chloride ions, electrolyte concentration, and pH of the external solutions. The results obtained are further explained in terms of a theoretical continuous model. The combination of well-established chemical procedures (thiol and self-assembled monolayer formation chemistry, electroless plating, ion track etching) and physical models (two-region pore and Nernst-Planck equations) permits the obtainment of a new nanopore with high current rectification ratios. The single pore could be scaled up to multipore membranes of potential interest for pH sensing and chemical actuators.
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Molecular Docking Based Screening of Plant Flavonoids as Dengue NS1 Inhibitors.
Bioinformation
PUBLISHED: 07-22-2014
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Dengue infection has turned into a serious health concern globally due to its high morbidity rate and a high possibility of increase in its mortality rate on the account of unavailability of any proper treatment for severe dengue infection. The situation demands an urgent development of efficient and practicable treatment to deal with Dengue virus (DENV). Flavonoids, a class of phytochemicals present in medicinal plants, possess anti-viral activity and can be strong drug candidates against viruses. NS1 glycoprotein of Dengue virus is involved in its RNA replication and can be a strong target for screening of drugs against this virus. Current study focuses on the identification of flavonoids which can block Asn-130 glycosylation site of Dengue virus NS1 to inhibit viral replication as glycosylation of NS1 is required for its biological functioning. Molecular docking approach was used in this study and the results revealed that flavonoids have strong potential interactions with active site of NS1. Six flavonoids (Deoxycalyxin A; 3,5,7,3',4'-pentahydroxyflavonol-3-O-beta-D-galactopyranoside; (3R)-3',8-Dihydroxyvestitol; Sanggenon O; Epigallocatechin gallate; Chamaejasmin) blocked the Asn-130 glycosylation site of NS1 and could be able to inhibit the viral replication. It can be concluded from this study that these flavonoids could serve as antiviral drugs for dengue infections. Further in-vitro analyses are required to confirm their efficacy and to evaluate their drug potency.
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Modelling and simulation of mutant alleles of breast cancer metastasis suppressor 1 (BRMS1) gene.
Bioinformation
PUBLISHED: 07-22-2014
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Computational tools occupy the prime position in the analysis of large volume of post-genomic data. These tools have advantage over the wet lab experiments in terms of high coverage, cost and time. Breast cancer is the most common cancer in females worldwide. It is a genetically heterogeneous disorder and many genes are involved in the pathway of the disease. Mutations in metastasis suppressor gene are the major cause of the disease. In this study, the effects of mutations in breast cancer metastasis suppressor 1gene upon protein structure and function were examined by means of computational tools and information from databases.This study can be useful to predict the potential effect of every allelic variant, devise new biological experiments and to interpret and predict the patho-physiological impact of new mutations or non-synonymous polymorphisms.
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Phylogenetic and Comparative Sequence Analysis of Thermostable Alpha Amylases of kingdom Archea, Prokaryotes and Eukaryotes.
Bioinformation
PUBLISHED: 07-22-2014
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Alpha amylase family is generally defined as a group of enzymes that can hydrolyse and transglycosylase ?-(1, 4) or ?-(1, 6) glycosidic bonds along with the preservation of anomeric configuration. For the comparative analysis of alpha amylase family, nucleotide sequences of seven thermo stable organisms of Kingdom Archea i.e. Pyrococcus furiosus (100-105°C), Kingdom Prokaryotes i.e. Bacillus licheniformis (90-95°C), Geobacillus stearothermophilus (75°C), Bacillus amyloliquefaciens (72°C), Bacillus subtilis (70°C) and Bacillus KSM K38 (55°C) and Eukaryotes i.e. Aspergillus oryzae (60°C) were selected from NCBI. Primary structure composition analysis and Conserved sequence analysis were conducted through Bio Edit tools. Results from BioEdit shown only three conserved regions of base pairs and least similarity in MSA of the above mentioned alpha amylases. In Mega 5.1 Phylogeny of thermo stable alpha amylases of Kingdom Archea, Prokaryotes and Eukaryote was handled by Neighbor-Joining (NJ) algorithm. Mega 5.1 phylogenetic results suggested that alpha amylases of thermo stable organisms i.e. Pyrococcus furiosus (100-105°C), Bacillus licheniformis (90-95°C), Geobacillus stearothermophilus (75°C) and Bacillus amyloliquefaciens (72°C) are more distantly related as compared to less thermo stable organisms. By keeping in mind the characteristics of most thermo stable alpha amylases novel and improved features can be introduced in less thermo stable alpha amylases so that they become more thermo tolerant and productive for industry.
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Effect of ketoprofen on lactic dehydrogenase from human platelets.
Adv Clin Exp Med
PUBLISHED: 07-01-2014
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In different clinical investigations of thrombocytopenia, ketoprofen was found to be the associated cause. Ketoprofen alone or in combination with other therapeutic regimens leads to a decrease in platelet count. Thrombocytopenia due to ketoprofen use can be a threatening condition to the patients who require uncompromised platelet function.
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In Silico Identification and Conservation Analysis of B-cell and T-Cell Epitopes of Hepatitis C Virus 3a Genotype Enveloped Glycoprotein 2 From Pakistan: A Step Towards Heterologous Vaccine Design.
Hepat Mon
PUBLISHED: 06-01-2014
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Hepatitis C virus (HCV) is known for the eminent global disease burden responsible for encumbering public health. Development of an effective vaccine is the major need of the day; however, several obstacles loom ahead of this objective. One of the major barriers is that as a RNA virus, it mutates rapidly resulting in high sequence divergence and several viral isolates in the world. Theglycoprotein 2 (gpE2) is the primary component of HCV envelope with direct interaction with the host cell surface receptors; it is an indispensable target of neutralizing antibodies and hence, should be a fundamental component of vaccine design.
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Di-?-chlorido-bis-(chlorido-{N'-[phen-yl(pyridin-2-yl-?N)methyl-idene]pyridine-2-carbohydrazide-?(2) N',O}cadmium).
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 06-01-2014
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The title compound, [Cd2Cl4(C18H14N4O)2], was obtained from the reaction of Cd(NO3)2·4H2O with 2-phenyl-pyridine-keton picolinoyl hydrazone and sodium chloride. Each Cd(2+) cation is coordinated by two N atoms and one O atom of the tridentate ligand and three chloride anions, forming a distorted CdNOCl3 octahedron. Each pair of adjacent metal cations is linked by two bridging chloride ligands, resulting in a dinuclear complex unit. The mol-ecular conformation is stabilized by intra-molecular N-H?N and C-H?O hydrogen bonds. In the crystal, mol-ecules are linked by nonclassical C-H?O and C-H?Cl hydrogen bonds into a three-dimensional network. In addition, ?-? stacking inter-actions [centroid-centroid distances = 3.777?(2) and 3.631?(2)?Å] contribute to the stabilization of the crystal packing.
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Wide range photodetector based on catalyst free grown indium selenide microwires.
ACS Appl Mater Interfaces
PUBLISHED: 05-29-2014
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We first report the catalyst free growth of indium selenide microwires through a facile approach in a horizontal tube furnace using indium and selenium elemental powders as precursors. The synthesized microwires are ?-phase, high quality, single crystalline and grown along the [112?0] direction. The wires have a uniform diameter of ?1 ?m and lengths of several micrometers. Photodetectors fabricated from synthesized microwires show reliable and stable photoresponse exhibiting a photoresponsivity of 0.54 A/W, external quantum efficiency of 1.23 at 633 nm with 4 V bias. The photodetector has a reasonable response time of 0.11 s and specific detectivity of 3.94 × 10(10) Jones at 633 nm with a light detection range from 350 to 1050 nm, covering the UV-vis-NIR region. The photoresponse shown by single wire is attributed to direct band gap (Eg = 1.3 eV) and superior single crystalline quality. The photoresponsive studies of single microwires clearly suggest the use of this new and facile growth technique without using catalysts for fabrication of indium selenide microwires in next-generation sensors and detectors for commercial and military applications.
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CD 10 expression intensity in various grades and stages of urothelial carcinoma of urinary bladder.
J Coll Physicians Surg Pak
PUBLISHED: 05-23-2014
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To evaluate CD10 expression in urothelial carcinoma of the urinary bladder and the association of immunohistochemical (IHC) CD10 expression intensity with grade and stage.
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OVGP1 is expressed in the canine oviduct at the time and place of oocyte maturation and fertilization.
Mol. Reprod. Dev.
PUBLISHED: 05-12-2014
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In the dog, oocyte maturation, fertilization, and early embryo development take place within the oviduct in the presence of increasing circulating progesterone (P4) levels. Expression of the oviduct-specific glycoprotein 1 (OVGP1), known in other species to be estrogen-dependent, was explored by real-time quantitative reverse-transcriptase PCR, Western blotting, and immunohistochemistry in oviducts from adult Beagle bitches during anestrus and at five specific time periods around ovulation: during pro-estrus before the luteinizing hormone (LH) peak (Pre-LH); after the LH peak and before ovulation (Pre-ov); and at Days 1, 4, and 7 after ovulation (n?=?6 bitches per stage). Plasma estradiol-17? (E2) and P4 were assayed at all stages. The expression of canine OVGP1 (cOVGP1) was undetectable during anestrus, increased significantly from Pre-LH to Day 1 in parallel with a decrease in plasma E2-to-P4 levels, remained high at Day 4, then decreased at Day 7 in parallel with an increase in plasma P4 levels. In contrast to other mammals, the expression of cOVGP1 was higher in the isthmus than in the ampulla at all stages. In order to explore the potential regulation of cOVGP1 expression by steroids, the 5'-flanking region of the corresponding gene was analyzed for the presence of estrogen- (ERE) and P4-response-element (PRE). An imperfect ERE and three half-ERE were found in this region, but no PREs. In conclusion, cOVGP1 is highly expressed at the time and site of oocyte maturation and fertilization, and is probably under E2 regulation. Further studies are needed to identify the potential roles of cOVGP1 in each process. Mol. Reprod. Dev. 81: 972-982, 2014. © 2014 Wiley Periodicals, Inc.
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Synthesis of carboxymethyl cellulose from waste of cotton ginning industry.
Carbohydr Polym
PUBLISHED: 05-12-2014
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The aim of present work was to isolate cellulose from cotton gin waste (CGW) and synthesis of carboxymethyl cellulose (CMC) from it. Scoured and bleached CGW was used to investigate the effects of temperature, reaction time, acid-base concentration on the physiology of the resultant cellulose polymer. The isolated cellulose from CGW was converted to CMC by etherification using sodium monochloroacetic acid and different sodium hydroxide (NaOH) concentrations (5-40 g/100mL) were tested to get high quality product. The optimum condition for carboxymethylation was found to be 20 g/100mL NaOH which provided the highest viscosity and degree of substitution (DS=0.874). Isolated cellulose and CMC were characterized using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). FT-IR analysis revealed that the produced cellulose was of very good quality. Furthermore, X-ray diffraction (XRD) analysis spotlighted crystalline nature of cellulose. SEM images showed rough structure of cellulose while that of the CMC had a smooth surface. This optimized method will be tested at pilot scale in collaboration with local industry.
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Molybdenum trioxide nanoparticles with intrinsic sulfite oxidase activity.
ACS Nano
PUBLISHED: 04-09-2014
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Sulfite oxidase is a mitochondria-located molybdenum-containing enzyme catalyzing the oxidation of sulfite to sulfate in the amino acid and lipid metabolism. Therefore, it plays a major role in detoxification processes, where defects in the enzyme cause a severe infant disease leading to early death with no efficient or cost-effective therapy in sight. Here we report that molybdenum trioxide (MoO3) nanoparticles display an intrinsic biomimetic sulfite oxidase activity under physiological conditions, and, functionalized with a customized bifunctional ligand containing dopamine as anchor group and triphenylphosphonium ion as targeting agent, they selectively target the mitochondria while being highly dispersible in aqueous solutions. Chemically induced sulfite oxidase knockdown cells treated with MoO3 nanoparticles recovered their sulfite oxidase activity in vitro, which makes MoO3 nanoparticles a potential therapeutic for sulfite oxidase deficiency and opens new avenues for cost-effective therapies for gene-induced deficiencies.
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Enhancing business intelligence by means of suggestive reviews.
ScientificWorldJournal
PUBLISHED: 03-25-2014
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Appropriate identification and classification of online reviews to satisfy the needs of current and potential users pose a critical challenge for the business environment. This paper focuses on a specific kind of reviews: the suggestive type. Suggestions have a significant influence on both consumers' choices and designers' understanding and, hence, they are key for tasks such as brand positioning and social media marketing. The proposed approach consists of three main steps: (1) classify comparative and suggestive sentences; (2) categorize suggestive sentences into different types, either explicit or implicit locutions; (3) perform sentiment analysis on the classified reviews. A range of supervised machine learning approaches and feature sets are evaluated to tackle the problem of suggestive opinion mining. Experimental results for all three tasks are obtained on a dataset of mobile phone reviews and demonstrate that extending a bag-of-words representation with suggestive and comparative patterns is ideal for distinguishing suggestive sentences. In particular, it is observed that classifying suggestive sentences into implicit and explicit locutions works best when using a mixed sequential rule feature representation. Sentiment analysis achieves maximum performance when employing additional preprocessing in the form of negation handling and target masking, combined with sentiment lexicons.
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Biogenic synthesis of palladium nanoparticles using Pulicaria glutinosa extract and their catalytic activity towards the Suzuki coupling reaction.
Dalton Trans
PUBLISHED: 03-13-2014
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Green synthesis of nanomaterials finds the edge over chemical methods due to its environmental compatibility. Herein, we report a facile and eco-friendly method for the synthesis of palladium (Pd) nanoparticles (NPs) using an aqueous solution of Pulicaria glutinosa, a plant widely found in a large region of Saudi Arabia, as a bioreductant. The as-prepared Pd NPs were characterized using ultraviolet-visible (UV-vis) spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform-infrared spectroscopy (FT-IR). The hydroxyl groups of the plant extract (PE) molecules were found mainly responsible for the reduction and growth of Pd NPs. FT-IR analysis confirmed the dual role of the PE, both as a bioreductant as well as a capping ligand, which stabilizes the surface of Pd NPs. The crystalline nature of the Pd NPs was identified using XRD analysis which confirmed the formation of a face-centered cubic structure (JCPDS: 87-0641, space group: Fm3m (225)). Furthermore, the as-synthesized Pd NPs demonstrated excellent catalytic activity towards the Suzuki coupling reaction under aqueous and aerobic conditions. Kinetic studies of the catalytic reaction monitored using GC confirmed that the reaction completes in less than 5 minutes.
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Changing pattern of malignancies: analysis of histopathology based tumour registry data and comparison of three decades at Armed Forces Institute of Pathology, Rawalpindi, Pakistan.
J Pak Med Assoc
PUBLISHED: 03-11-2014
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To assess the pattern of malignancies from tumour registry data and to find any changing pattern by comparing corresponding data from earlier periods.
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Luteovirus: insights into pathogenicity.
Arch. Virol.
PUBLISHED: 02-21-2014
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Luteoviruses are economically important plant viruses, infecting almost all cereals throughout the world. Idiosyncrasies related to this virus group may be a strategic consequence of viral genome compression. However, many fundamental questions have yet to be resolved. This review summarizes selected findings covering molecular aspects of pathogenesis relating to plant-infecting RNA viruses in general, and luteoviruses in specific. These studies enhance our understanding of the replication structures and the virus infection pathways.
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Ambient surface analysis of organic monolayers using direct analysis in real time Orbitrap mass spectrometry.
Anal. Chem.
PUBLISHED: 02-13-2014
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A better characterization of nanometer-thick organic layers (monolayers) as used for engineering surface properties, biosensing, nanomedicine, and smart materials will widen their application. The aim of this study was to develop direct analysis in real time high-resolution mass spectrometry (DART-HRMS) into a new and complementary analytical tool for characterizing organic monolayers. To assess the scope and formulate general interpretation rules, DART-HRMS was used to analyze a diverse set of monolayers having different chemistries (amides, esters, amines, acids, alcohols, alkanes, ethers, thioethers, polymers, sugars) on five different substrates (Si, Si3N4, glass, Al2O3, Au). The substrate did not play a major role except in the case of gold, for which breaking of the weak Au-S bond that tethers the monolayer to the surface, was observed. For monolayers with stronger covalent interfacial bonds, fragmentation around terminal groups was found. For ester and amide-terminated monolayers, in situ hydrolysis during DART resulted in the detection of ions characteristic of the terminal groups (alcohol, amine, carboxylic acid). For ether and thioether-terminated layers, scission of C-O or C-S bonds also led to the release of the terminal part of the monolayer in a predictable manner. Only the spectra of alkane monolayers could not be interpreted. DART-HRMS allowed for the analysis of and distinction between monolayers containing biologically relevant mono or disaccharides. Overall, DART-HRMS is a promising surface analysis technique that combines detailed structural information on nanomaterials and ultrathin films with fast analyses under ambient conditions.
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Identification of a distinct strain of cotton leaf curl Burewala virus.
Arch. Virol.
PUBLISHED: 01-26-2014
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Cotton leaf curl disease (CLCuD) is the major biotic limitation to cotton production in Pakistan and northwestern India. The disease is caused by various distinct viruses of the genus Begomovirus (family Geminiviridae) in association with a disease-specific betasatellite - cotton leaf curl Multan betasatellite (CLCuMB). Since 2001, when resistance to CLCuD in cotton was broken, only one virus was consistently identified in cotton exhibiting CLCuD symptoms in Punjab province (Pakistan) - cotton leaf curl Burewala virus (CLCuBuV). An analysis of all CLCuBuV isolates available in the databases showed these to represent only a single strain, based on currently applicable criteria. Virus and betasatellite clones were obtained from a leaf sample (isolate C49) collected from a CLCuD symptomatic cotton plant in Layyah district, Punjab province, in 2012. Analysis of the sequence of the betasatellite showed this to be an isolate of CLCuMB containing the recombinant fragment typical of this satellite post-resistance-breaking. The virus was shown it to be an isolate of CLCuBuV but to be distinct from all previously characterised isolates and to represent a distinct strain. In common with previous CLCuBuV isolates, the virus from C49 is a recombinant containing sequences derived from viruses of two species that were prevalent in cotton pre-resistance-breaking but with distinct recombination break sites. As was the case with the earlier CLCuBuV, the newly identified strain of CLCuBuV lacks an intact transcriptional activator protein.
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Biotinylation of the rhizobial cyclic ?-glucans and succinoglycans crucial for symbiosis with legumes.
Carbohydr. Res.
PUBLISHED: 01-22-2014
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The cyclic ?-glucans and succinoglycans produced by rhizobia are required for nodulation during symbiosis with legume hosts. However, only gene deletion analyses have been used to investigate their biological importance. For future studies on the physiological activity of those during symbiosis, biochemical methods need to be developed with separate carbohydrate compounds. Here, we isolated and purified rhizobial cellular carbohydrates using various chromatographic methods. Purified cyclic ?-glucans, cyclosophoraoses, were monofunctionalized with biotin using the following three steps: tosylation, azidation, and amination. The mono-6-amino-cyclosophoraoses were linked with biotinamidohexanoic acid N-hydroxysuccinimide ester. Succinoglycans and monomers were tagged with biotinamidocaproyl hydrazide at the reducing sugar via reductive amination. The resulting biotinylated rhizobial carbohydrates were characterized by Fourier transform infrared and nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and electrospray ionization mass spectrometry. The resulting neoglycoconjugates can be used as solid probes to study putative plant receptors and for non-invasive imaging for in vivo tracing.
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Hypospadias repair: a single centre experience.
Plast Surg Int
PUBLISHED: 01-20-2014
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Objectives. To determine the demographics and analyze the management and factors influencing the postoperative complications of hypospadias repair. Settings. Hayatabad Medical Complex Peshawar, Pakistan, from January 2007 to December 2011. Material and Methods. All male patients presenting with hypospadias irrespective of their ages were included in the study. The data were acquired from the hospital's database and analyzed with Statistical Package for Social Sciences (SPSS). Results. A total of 428 patients with mean age of 8.12 ± 5.04 SD presented for hypospadias repair. Midpenile hypospadias were the most common. Chordee, meatal abnormalities, cryptorchidism, and inguinal hernias were observed in 74.3%, 9.6%, 2.8%, and 2.1% cases, respectively. Two-stage (Bracka) and TIP (tubularized incised urethral plate) repairs were performed in 76.2% and 20.8% of cases, respectively. The most common complications were edema and urethrocutaneous fistula (UCF). The complications were significantly lower in the hands of specialists than residents (P-value = 0.0086). The two-stage hypospadias repair resulted in higher complications frequency than single-stage repair (P value = 0.0001). Conclusion. Hypospadias surgery has a long learning curve because it requires a great deal of temperament, surgical skill and acquaintance with magnifications. Single-stage repair should be encouraged wherever applicable due to its lower postoperative complications.
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Multifunctional g-C(3)N(4) nanofibers: a template-free fabrication and enhanced optical, electrochemical, and photocatalyst properties.
ACS Appl Mater Interfaces
PUBLISHED: 01-03-2014
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We have developed a facile, scale up, and efficient method for the preparation of graphitic-C3N4 nanofibers (GCNNFs) as electrodes for supercapacitors and photocatalysts. The as-synthesized GCNNFs have 1D structure with higher concentration of nitrogen that is favorable for higher conductivity and electrochemical performance. Secondly, the high surface area of GCNNF provides a large electrode-electrolyte contact area, sufficient light harvesting and mass transfer, as well as increased redox potential. Thus, the GCNNF supercapacitor electrode shows high capacitance of 263.75 F g(-1) and excellent cyclic stability in 0.1 M Na2SO4 aqueous electrolyte with the capacitance retention of 93.6% after 2000 cycles at 1 A g(-1) current density. GCNNFs exhibit high capacitance of 208 F g(-1) even at 10 A g(-1), with the appreciable capacitance retention of 89.5%, which proves its better rate capability. Moreover, the GCNNF shows enhanced photocatalytic activity in the photodegradation of RhB in comparison to the bulk graphitic-C3N4 (GCN). The degradation rate constant of GCNNF photocatalyst is almost 4 times higher than GCN. The enhanced photocatalytic activity of GCNNF is mainly due to the higher surface area, appropriate bandgap, and fewer defects in GCNNF as compared to GCN. As an economical precursor (melamine) and harmless, facile, and template-free synthesis method with excellent performance both in supercapacitors and in photodegradation, GCNNF is a strong candidate for energy storage and environment protection applications.
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A preliminary investigation of user perception and behavioral intention for different review types: customers and designers perspective.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Existing opinion mining studies have focused on and explored only two types of reviews, that is, regular and comparative. There is a visible gap in determining the useful review types from customers and designers perspective. Based on Technology Acceptance Model (TAM) and statistical measures we examine users' perception about different review types and its effects in terms of behavioral intention towards using online review system. By using sample of users (N = 400) and designers (N = 106), current research work studies three review types, A (regular), B (comparative), and C (suggestive), which are related to perceived usefulness, perceived ease of use, and behavioral intention. The study reveals that positive perception of the use of suggestive reviews improves users' decision making in business intelligence. The results also depict that type C (suggestive reviews) could be considered a new useful review type in addition to other types, A and B.
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Experimental study of direct laser deposition of Ti-6Al-4V and Inconel 718 by using pulsed parameters.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Laser direct metal deposition (LDMD) has developed from a prototyping to a single metal manufacturing tool. Its potential for creating multimaterial and functionally graded structures is now beginning to be explored. This work is a first part of a study in which a single layer of Inconel 718 is deposited on Ti-6Al-4V substrate. Single layer tracks were built at a range of powder mass flow rates using a coaxial nozzle and 1.5?kW diode laser operating in both continuous and pulsed beam modes. This part of the study focused on the experimental findings during the deposition of Inconel 718 powder on Ti-6Al-4V substrate. Scanning electron microscopy (SEM) and X-ray diffraction analysis were performed for characterization and phase identification. Residual stress measurement had been carried out to ascertain the effects of laser pulse parameters on the crack development during the deposition process.
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Performance analysis of a semiactive suspension system with particle swarm optimization and fuzzy logic control.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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This paper uses a quarter model of an automobile having passive and semiactive suspension systems to develop a scheme for an optimal suspension controller. Semi-active suspension is preferred over passive and active suspensions with regard to optimum performance within the constraints of weight and operational cost. A fuzzy logic controller is incorporated into the semi-active suspension system. It is able to handle nonlinearities through the use of heuristic rules. Particle swarm optimization (PSO) is applied to determine the optimal gain parameters for the fuzzy logic controller, while maintaining within the normalized ranges of the controller inputs and output. The performance of resulting optimized system is compared with different systems that use various control algorithms, including a conventional passive system, choice options of feedback signals, and damping coefficient limits. Also, the optimized semi-active suspension system is evaluated for its performance in relation to variation in payload. Furthermore, the systems are compared with respect to the attributes of road handling and ride comfort. In all the simulation studies it is found that the optimized fuzzy logic controller surpasses the other types of control.
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Asymmetric Synthesis of 4,1-Benzoxazepine-2,5-Diones - Effect of the Halogen of (2S)-?-Haloacids.
Molecules
PUBLISHED: 11-28-2013
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Novel chiral 4,1-benzoxazepine-2,5-diones have been unusually synthesized in a single step by exploiting the chiral pool methodology. Substituted anthranilic acids afford N-acylanthranilic acids and (3R)-3-alkyl-4,1-benzoxazepines-2,5-dione upon coupling with ?-chloroacids or ?-bromoacids, respectively.
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Controlled synthesis of linear and branched Au@ZnO hybrid nanocrystals and their photocatalytic properties.
Nanoscale
PUBLISHED: 08-30-2013
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Colloidal Au@ZnO hybrid nanocrystals with linear and branched shape were synthesized. The number of ZnO domains on the Au seeds can be controlled by the solvent mixture. Imidazole-functionalized Au@ZnO hybrid nanocrystals were soluble in water and exhibited a greatly enhanced photocatalytic activity compared to ZnO nanocrystals. The pristine heterodimeric NPs were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Vis spectroscopy.
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Translational and rotational diffusion of gold nanorods near a wall.
J Chem Phys
PUBLISHED: 08-17-2013
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We measured the rotational and translational diffusivity of dilute gold nanorods in aqueous suspension close to a hard planar wall. Therefore, resonance enhanced dynamic light scattering, an evanescent technique, was applied, making use of the strong scattering intensity near the longitudinal surface plasmon resonance frequency of the particle. We observed a slowing down beyond the known hydrodynamic models.
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Solubility enhancement of ?-naphthoflavone by synthesized hydroxypropyl cyclic-(1?2)-?-d-glucans (cyclosophoroases).
Carbohydr Polym
PUBLISHED: 08-03-2013
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Rhizobium leguminosarum produces unbranched cyclic ?-1,2-glucans, cyclosophoraoses (Cys). In the present study, Cys were modified with hydroxypropyl groups via a one step chemical derivatization and the complexation ability and solubility enhancement of hydroxypropyl cyclosophoraoses (HP Cys) with ?-naphthoflavone (?-NF) were investigated. In the presence of HP Cys, the aqueous solubility of ?-NF greatly increased up to 257-fold. Complex formation of HP Cys and ?-NF was confirmed by nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR) spectroscopy, and differential scanning calorimetry (DSC). Furthermore, the morphological structure of ?-NF with HP Cys was examined using scanning electron microscopy (SEM). A hypothetical model was proposed based on molecular dynamics (MD) simulations and a docking study of ?-NF with HP Cys. Our results suggest that HP Cys form complexes with ?-NF and can be utilized as a promising solubilizer. This is the first study to identify carbohydrates that can enhance the solubility of ?-NF.
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Synthesis, Chemical Characterization, DNA Binding, Antioxidant, Antibacterial, and Antifungal Activities of Ferrocence Incorporated Selenoureas.
J. Biochem. Mol. Toxicol.
PUBLISHED: 08-03-2013
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Ferrocene-incorporated selenoureas 1-(4-methoxybenzoyl)-3-(4-ferrocenylphenyl)selenourea (P4Me), 1-(3-methoxybenzoyl)-3-(4-ferrocenylphenyl)selenourea (P3Me), and 1-(2-methoxybenzoyl)-3-(4-ferrocenylphenyl)selenourea (P2Me) were synthesized and characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, atomic absorption spectroscopy, CHNS, and single-crystal X-ray diffraction. DNA interaction of the compounds was investigated with cyclic voltammetry, UV-visible spectroscopy, and viscometry, which is a prerequisite for anticancer agents. Drug-DNA binding constant was found to vary in the sequence: KP4Me (4.9000 × 10(4) M(-1) ) > KP2Me (2.318 × 10(4) M(-1) ) > KP3Me (1.296 × 10(4) M(-1) ). Antioxidant (1,1-diphenyl-2-picrylhydrazyl), antifungal (against Faussarium solani and Helmentosporium sativum), and antibacterial (against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis) activities have also been reported in addition.
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1,3-Bis[(5-amino-furan-2-yl)meth-yl]-3,4,5,6-tetra-hydro-pyrimidin-1-ium hexa-fluoro-phosphate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 08-01-2013
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The asymmetric unit of the title salt, C16H21N2O2 (+)·PF6 (-), contains half of the whole ion pair, which has crystallographic mirror symmetry. Two F atoms related by the mirror plane are disordered over two sites of equal occupancy. The dihedral angle between the central ring and the furan ring is 59.3?()°. In the crystal, the anions and cations are linked through C-H?F inter-actions, forming a three-dimensional network.
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Breast lesions in adolescents and young women in Pakistan--a 5 year study of significance of early recognition.
Asian Pac. J. Cancer Prev.
PUBLISHED: 07-27-2013
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Breast cancer is the most frequent malignant disease amongst young women. If we review local data in Pakistan then breast cancer represents approximately a third of all cancers in females. The age standardized incidence rate (ASR) world per 100,000 is 53.8 and crude incidence rate is 30.9. We have observed during our surgical pathology practice and it is also reported by other Asian studies that breast carcinoma is amongst the leading malignancies in the region and the patients are at least a decade younger than counterparts in developed nations. Age is an important issue in effective screening, diagnosis and management of breast cancer, especially in this geographical region where late presentation and poor prognosis are a hallmark of the disease.
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Prediction of Protein Structure Classes Using Hybrid Space of Multi-Profile Bayes and bi-gram Probability Feature Spaces.
J. Theor. Biol.
PUBLISHED: 07-26-2013
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Proteins are the executants of biological functions in living organisms. Comprehension of protein structure is a challenging problem in the era of proteomics, computational biology, and bioinformatics because of its pivotal role in protein folding patterns. Owing to the large exploration of protein sequences in protein databanks and intricacy of protein structures, experimental and theoretical methods are insufficient for prediction of protein structure classes. Therefore, it is highly desirable to develop an accurate, reliable, and high throughput computational model to predict protein structure classes correctly from polygenetic sequences. In this regards, we propose a promising model employing hybrid descriptor space in conjunction with optimized evidence-theoretic K-nearest neighbor algorithm. Hybrid space is the composition of two descriptor spaces including Multi-profile Bayes and bi-gram probability. In order to enhance the generalization power of the classifier, we have selected high discriminative descriptors from the hybrid space using particle swarm optimization, a well-known evolutionary feature selection technique. Performance evaluation of the proposed model is performed using the jackknife test on three low similarity benchmark datasets including 25PDB, 1189, and 640. The success rates of the proposed model are 87.0%, 86.6%, and 88.4%, respectively on the three benchmark datasets. The comparative analysis exhibits that our proposed model has yielded promising results compared to the existing methods in the literature. In addition, our proposed prediction system might be helpful in future research particularly in cases where the major focus of research is on low similarity datasets.
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Evaluation of silica-H2SO4 as an efficient heterogeneous catalyst for the synthesis of chalcones.
Molecules
PUBLISHED: 07-19-2013
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We report an efficient silica-H2SO4 mediated synthesis of a variety of chalcones that afforded the targeted compounds in very good yield compared to base catalyzed solvent free conditions as well as acid or base catalyzed refluxing conditions.
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Synthesis, spectroscopic, X-ray crystal structure, biological and DNA interaction studies of organotin(IV) complexes of 2-(4-ethoxybenzylidene) butanoic acid.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-18-2013
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Six organotin(IV) carboxylates of the type R2SnL2 [R=CH3 (1), n-C4H9 (2), n-C8H17 (3)] and R3SnL [R=CH3 (4), n-C4H9 (5), C6H5 (6), where L=2-(4-ethoxybenzylidene) butanoic acid, have been synthesized and characterized by elemental analysis, FT-IR and NMR ((1)H, (13)C). The complex (1) was also analyzed by single crystal X-ray analysis. The complexes were screened for antimicrobial, cytotoxic and anti-tumor activities. The results showed significant activity in each area of the activity with few exceptions. DNA interactions studies of ligand HL and representative complex 2 were investigated by UV-Visible absorption spectroscopy and viscosity measurements. The results showed that both ligand HL and complex 2 interact with SS-DNA via intercalation as well as minor groove binding.
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Polyacrylonitrile block copolymers for the preparation of a thin carbon coating around TiO2 nanorods for advanced lithium-ion batteries.
Macromol Rapid Commun
PUBLISHED: 07-10-2013
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Herein, a new method for the realization of a thin and homogenous carbonaceous particle coating, made by carbonizing RAFT polymerization derived block copolymers anchored on anatase TiO2 nanorods, is presented. These block copolymers consist of a short anchor block (based on dopamine) and a long, easily graphitizable block of polyacrylonitrile. The grafting of such block copolymers to TiO2 nanorods creates a polymer shell, which can be visualized by atomic force microscopy (AFM). Thermal treatment at 700 °C converts the polyacrylonitrile block to partially graphitic structures (as determined by Raman spectroscopy), establishing a thin carbon coating (as determined by transmission electron microscopy, TEM, analysis). The carbon-coated TiO2 nanorods show improved electrochemical performance in terms of achievable specific capacity and, particularly, long-term cycling stability by reducing the average capacity fading per cycle from 0.252 mAh g(-1) to only 0.075 mAh g(-1) .
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Stereoselective Synthesis of (3R)-3-Alkyl-4,1-Benzoxazepine-2,5-Diones.
Chirality
PUBLISHED: 06-17-2013
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Novel 3-alkyl-4,1-benzoxazepine-2,5-diones were synthesized in good ee exploiting the chiral pool methodology, an economical way of asymmetric synthesis. Various anthranilic acids are coupled with different ?-haloacids to afford N-acylated anthranilic acid intermediates which undergo cyclization to (3R)-3-alkyl-4,1-benzoxazepines-2,5-diones. Chirality 00:000-000, 2013. © 2013 Wiley Periodicals, Inc.
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Development of an in-house hospital information system in a hospital in Pakistan.
Int J Med Inform
PUBLISHED: 05-28-2013
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To review our experience of development and implementation of an electronic hospital information system, its costs and return on investment as well as incorporation of some key quality standards.
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Melanotic neuroectodermal tumour of infancy: a rare brain tumour of childhood.
J Coll Physicians Surg Pak
PUBLISHED: 05-16-2013
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Melanotic neuroectodermal tumour of infancy is a rare, mostly benign but locally aggressive tumour of neural crest cell origin occurring in infants. The most commonly affected anatomic site is the maxilla. Such tumours of the brain and skull are very rare. We present the case of an 8 months old baby girl whose presenting complaint was a swelling in the scalp for 6 months. She was otherwise asymptomatic. CT imaging confirmed the presence of an osteolytic tumour in the anterior parasagittal skull with dural involvement. The tumour was surgically excised enbloc. The patient has been well at 2 years follow-up without any evidence of recurrence.
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Pentynyl dextran as a support matrix for immobilization of serine protease subtilisin Carlsberg and its use for transesterification of N-acetyl-L-phenylalanine ethyl ester in organic media.
Bioprocess Biosyst Eng
PUBLISHED: 05-14-2013
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In this study, serine protease (subtilisin Carlsberg) was immobilized on pentynyl dextran (PyD, O-alkynyl ether of dextran, 1) and used for the transesterification of N-acetyl-L-phenylalanine ethyl ester (2) with different aliphatic (1-propanol, 1-butanol, 1-pentanol, 1-hexanol) and aromatic (benzyl alcohol, 2-phenyl ethanol, 4-phenyl-1-butanol) alcohols in tetrahydrofuran (THF). The effect of carbon chain length in aliphatic and aromatic alcohols on initial and average transesterification rate, transesterification activity of immobilized enzyme and yield of the reaction under selected reaction conditions was investigated. The transesterification reactivity of the enzyme and yield of the reaction increased as the chain length of the alcohols decreased. Furthermore, almost no change in yield was observed when the immobilized enzyme was repeatedly used for selected alcohols over six cycles. Intrinsic fluorescence analysis showed that the catalytic activity of the immobilized enzyme in THF was maintained due to retention of the tertiary structure of the enzyme after immobilization on PyD (1).
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Protein subcellular localization in human and hamster cell lines: Employing local ternary patterns of fluorescence microscopy images.
J. Theor. Biol.
PUBLISHED: 05-03-2013
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Discriminative feature extraction technique is always required for the development of accurate and efficient prediction systems for protein subcellular localization so that effective drugs can be developed. In this work, we showed that Local Ternary Patterns (LTPs) effectively exploit small variations in pixel intensities; present in fluorescence microscopy based protein images of human and hamster cell lines. Further, Synthetic Minority Oversampling Technique is applied to balance the feature space for the classification stage. We observed that LTPs coupled with data balancing technique could enable a classifier, in this case support vector machine, to yield good performance. The proposed ensemble based prediction system, using 10-fold cross-validation, has yielded better performance compared to existing techniques in predicting various subcellular compartments for both 2D HeLa and CHO datasets. The proposed predictor is available online at: http://111.68.99.218/Protein_SubLoc/, which is freely accessible to the public.
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Assessment of xanthan gum based sustained release matrix tablets containing highly water-soluble propranolol HCl.
Acta Pol Pharm
PUBLISHED: 04-26-2013
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The present study was carried out to develop oral sustained release tablets of propranolol HCl by different ratios of drug : matrix. Tablets were prepared by direct compression technique using xanthan gum and lactose. All the formulations (tablets) were evaluated for thickness, diameter, hardness, friability, weight variation, content of active ingredient, in vitro dissolution using USP dissolution apparatus-II and swelling index. In case of dissolution, an inverse relationship was noted between amount of xanthan gum and release rate of propranolol HCl and the drug release was gradually enhanced as the amount of the lactose increased. The direct release was observed between swelling index and xanthan gum concentration. Significant difference in different media was observed in release profile, indicating that propranolol HCI has better solubility in HCI buffer pH 1.2. Moreover, dissolution data at differing stirring speeds was also analyzed, indicating that the drug release profile was at 50 rpm comparative to 100 rpm. The kinetic treatment showed the best fitted different mathematical models (zero order, first order, Higuchis, Hixson-Crowell and Korsmeyer Peppas model. Most of the formulations showed linearity in Higuchis model. The drug release from these tablets was by Fickian diffusion and anomalous (non-Fickian) mechanisms.
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MitProt-Pred: Predicting mitochondrial proteins of Plasmodium falciparum parasite using diverse physiochemical properties and ensemble classification.
Comput. Biol. Med.
PUBLISHED: 04-22-2013
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Mitochondrial protein of Plasmodium falciparum is an important target for anti-malarial drugs. Experimental approaches for detecting mitochondrial proteins are costly and time consuming. Therefore, MitProt-Pred is developed that utilizes Bi-profile Bayes, Pseudo Average Chemical Shift, Split Amino Acid Composition, and Pseudo Amino Acid Composition based features of the protein sequences. Hybrid feature space is also developed by combining different individual feature spaces. These feature spaces are learned and exploited through SVM based ensemble. MitProt-Pred achieved significantly improved prediction performance for two standard datasets. We also developed the score level ensemble, which outperforms the feature level ensemble.
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Self-cleaning antimicrobial surfaces by bio-enabled growth of SnO2 coatings on glass.
Nanoscale
PUBLISHED: 03-11-2013
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Conventional vapor-deposition techniques for coatings require sophisticated equipment and/or high-temperature resistant substrates. Therefore bio-inspired techniques for the fabrication of inorganic coatings have been developed in recent years. Inspired by the biology behind the formation of the intricate skeletons of diatoms orchestrated by a class of cationic polyamines (silaffins) we have used surface-bound spermine, a naturally occurring polyamine, to promote the fast deposition of homogeneous, thin and transparent biomimetic SnO2 coatings on glass surfaces. The bio-enabled SnO2 film is highly photoactive, i.e. it generates superoxide radicals (O2?(-)) upon sunlight exposure resulting in a strong degradation of organic contaminants and a strong antimicrobial activity. Upon illumination the biomimetic SnO2 coating exhibits a switchable amphiphilic behavior, which - in combination with its photoactivity - creates a self-cleaning surface. The intrinsic self-cleaning properties could lead to the development of new protective, antifouling coatings on various substrates.
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Immunolocalization of aquaporin-10 in tuberculous human ileum.
J Coll Physicians Surg Pak
PUBLISHED: 02-25-2013
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To determine the presence of AQP-10 in the ileum of patients suffering from intestinal tuberculosis.
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Graphene-type sheets of Nb(1-x)W(x)S2: synthesis and in situ functionalization.
Dalton Trans
PUBLISHED: 02-12-2013
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Enlightened by the discovery of graphenes, a variety of inorganic analogues have been synthesized and characterized in recent years. Solvated Nb1-xWxS2 analogues of graphene-type sheets were prepared by lithiation and exfoliation of multistacked Nb1-xWxS2 coin roll nanowires (CRNWs), followed by in situ functionalization with gold nanoparticles to synthesize gold-loaded Nb1-xWxS2/Au nanocomposites. The Nb1-xWxS2 nanosheets and the corresponding Nb1-xWxS2/Au nanocomposites were characterized by high resolution electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), scanning transmission electron microscopy (STEM), dynamic light scattering (DLS) and scanning force microscopy (AFM). The graphene-type sheets are stable in water and other solvents and can be functionalized similarly as chalcogen-terminated surfaces (e.g. with Au nanoparticles).
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Potential bioactive Schiff base compounds: synthesis, characterization, X-ray structures, biological screenings and interaction with Salmon sperm DNA.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-11-2013
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Three Schiff base compounds ofN-substituted benzohydrazide and sulfonohydrazide derivatives: N-(2-hydroxy-3-methoxybenzylidene)-4-tert-butyl- benzohydrazide (1), N-(5-bromo-2-hydroxybenzylidene)-4-tert-butylbenzohydrazide (2) and N-(2-hydroxy-3-methoxybenzylidene)-4-methylbenzenesulfonohydrazide (3) were synthesized and characterized by elemental analysis, FT-IR, (1)H, (13)C NMR spectroscopy and single crystal analysis. The title compounds have been screened for their biological activities including, antibacterial, antifungal, antioxidant, cytotoxic, enzymatic activities as well as interaction with SS-DNA which showed remarkable activities in each area of research. The DNA binding of the compounds 1-3 with SS-DNA has been carried out with absorption spectroscopy, which reveals the binding propensity towards SS-DNA via intercalation mode of interaction. The intercalative mode of interaction is also supported by viscometric results. The synthesized compounds were also found to be effective against alkaline phosphatase enzyme. They also show significant to good antimicrobial activity against six bacterial and five fungal strains. The MIC (minimum inhibitory concentration) for antibacterial activity ranges from 1.95-500 ?g/mL. Compounds 1-3 show cytotoxic activity comparable to the control. At higher conc. (100 ?g/L) compound 3 shows 100% activity means that it has killed all brine shrimps. They were also found to be effective antioxidant of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and show almost comparable antioxidant activity to that of the standard and known antioxidant, ascorbic acid.
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Silicatein conjugation inside nanoconfined geometries through immobilized NTA-Ni(II) chelates.
Chem. Commun. (Camb.)
PUBLISHED: 02-08-2013
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The chemical modification and bioconjugation processes inside confined geometries by His-tagged silicatein promote sensitive changes in the polarity and surface charge density that mainly contribute to the ionic current rectification properties of the single conical nanopores.
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Ethyl N-(2-benzoyl-3-oxo-3-phenyl-propano-yl)carbamate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 01-04-2013
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In the title compound, C(19)H(17)NO(5), the dihedral angle between the phenyl groups is 79.55?(15)°. The terminal eth-oxy group is disordered over two orientations in a 0.873?(6):0.127?(6) ratio. In the crystal, mol-ecules are linked by N-H?O and C-H?O hydrogen bonds into [001] chains which incorporate R(1) (2)(6) loops. A very weak C-H?? contact also occurs.
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4-(1-Methyl-eth-yl)-N-((E)-4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)aniline.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 01-03-2013
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In the title compound, C(22)H(24)N(4)O, the terminal and central benzene rings make dihedral angles of 52.7?(3) and 43.8?(2)°, respectively, with the triazole ring. The dihedral angle between the benzene rings is 8.9?(2)°. The crystal structure features C-H?? inter-actions. The atoms of the terminal propenyl group are disordered over two sets of sites, with a refined occupancy ratio of 0.714?(14):0.286?(14).
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Green synthesis of silver nanoparticles mediated by Pulicaria glutinosa extract.
Int J Nanomedicine
PUBLISHED: 01-01-2013
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The green synthesis of metallic nanoparticles (NPs) has attracted tremendous attention in recent years because these protocols are low cost and more environmentally friendly than standard methods of synthesis. In this article, we report a simple and eco-friendly method for the synthesis of silver NPs using an aqueous solution of Pulicaria glutinosa plant extract as a bioreductant. The as-prepared silver NPs were characterized using ultraviolet-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. Moreover, the effects of the concentration of the reductant (plant extract) and precursor solution (silver nitrate), the temperature on the morphology, and the kinetics of reaction were investigated. The results indicate that the size of the silver NPs varied as the plant extract concentration increased. The as-synthesized silver NPs were phase pure and well crystalline with a face-centered cubic structure. Further, Fourier-transform infrared spectroscopy analysis confirmed that the plant extract not only acted as a bioreductant but also functionalized the NPs surfaces to act as a capping ligand to stabilize them in the solvent. The developed eco-friendly method for the synthesis of NPs could prove a better substitute for the physical and chemical methods currently used to prepare metallic NPs commonly used in cosmetics, foods, and medicines.
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{4,4-Dimethyl-2,2-[(2,2-dimethyl-propane-1,3-di-yl)bis-(nitrilo-methanylyl-idene)]diphenolato}nickel(II) monohydrate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 12-11-2011
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In the title compound, [Ni(C(21)H(24)N(2)O(2))]·H(2)O, both the complex mol-ecule and the water mol-ecule lie on a twofold rotation axis. The Ni(II) ion is coordinated in a distorted square-planar geometry by the tetra-dentate ligand. The dihedral angle between the two symmetry-related benzene rings is 47.12?(8)°. In the crystal, pairs of symmetry-related O-H?O hydrogen bonds form R(2) (2)(6) ring motifs. In addition, there are weak inter-molecular C-H?O hydrogen bonds, and ?-? stacking inter-actions with a centroid-centroid distance of 3.4760?(8)?Å.
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4,6-Dichloro-2-{[(E)-(3-{[(E)-3,5-dichloro-2-hy-droxy-benzyl-idene]amino}-2,2-dimethyl-prop-yl)imino]-meth-yl}phenol.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 12-09-2011
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In the title compound, C(19)H(18)Cl(4)N(2)O(2), a potential tetra-dentate Schiff base ligand, the dihedral angle between the two benzene rings is 48.01?(10)°. The configuration about the two C=N bonds is E and two intra-molecular O-H?N hydrogen bonds make S(6) ring motifs. In the crystal, mol-ecules are linked along the b axis via inter-molecular C-H?Cl inter-actions. The crystal structure is further stabilized by an inter-molecular ?-? inter-action [centroid-centroid distance = 3.5744?(12)?Å].
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A prospective study of cefepime versus ticarcilline/clavulanate as empirical treatment of febrile neutropenia in lymphoma patients.
J Pak Med Assoc
PUBLISHED: 12-05-2011
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To check the effectiveness of ticarcillin clavulanate versus cefepime as monotherapy in febrile neutropenia in lymphoma patients and also to check tolerability profile of both drugs.
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Intraspinal neurenteric cyst--a rare entity.
J Pak Med Assoc
PUBLISHED: 12-01-2011
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Neurenteric cysts are uncommonly reported congenital abnormalities that are thought to be an abnormal connection between the endoderm and ectoderm during the 3rd week of life. We report a case of a 17 years old male who presented with one year history of pain in the right arm for which he had been taking pain killer medication from the local general practitioner. The pain progressed over several months and developed into numbness and weakness of the right arm. Magnetic resonance imaging revealed a cystic mass at the C7 to D2 location. The mass was removed surgically and the specimen sent to Armed Forces Institute of Pathology for histopathological examination. On the basis of morphological features, an endodermal mass was diagnosed as Intraspinal Neurenteric cyst.
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Protein subcellular localization of fluorescence imagery using spatial and transform domain features.
Bioinformatics
PUBLISHED: 11-15-2011
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Subcellular localization of proteins is one of the most significant characteristics of living cells. Prediction of protein subcellular locations is crucial to the understanding of various protein functions. Therefore, an accurate, computationally efficient and reliable prediction system is required.
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5-[(E)-(5-Bromo-2-hy-droxy-benzyl-idene)amino]-1,3,4-thia-diazole-2(3H)-thione.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 11-13-2011
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In the title mol-ecule, C(9)H(6)BrN(3)OS(2), the dihedral angle between the benzene ring and the five-membered ring is 5.5?(3)°. An intra-molecular O-H?N hydrogen bond forms an S(6) ring motif. In the crystal, N-H?S hydrogen bonds link mol-ecules into centrosymmetric dimers creating R(2) (2)(8) ring motifs. In addition, there are inter-molecular S?S [3.430?(2)?Å] contacts. The crystal used was a non-merohedral twin with a ratio of 0.113?(3):0.887?(3) for the components.
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(E)-5-[(2-Hy-droxy-5-meth-oxy-benzyl-idene)amino]-1,3,4-thia-diazole-2(3H)-thione.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 11-03-2011
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In the title thione-Schiff base compound, C(10)H(9)N(3)O(2)S(2), the dihedral angle between the benzene ring and the five-membered ring is 6.69?(8)°. An intra-molecular O-H?N hydrogen bond forms an S(2) (2)(6) ring. In the crystal, inversion dimers linked by pairs of N-H?S inter-actions occur, generating R(2) (2)(8) ring motifs. The crystal structure features a S?S contact [3.3776?(7)?Å], which is significantly shorter than the sum of the van der Waals radii (3.7?Å). The crystal structure also features C-H?O and ?-? inter-actions [centroid-centroid distances = 3.4636?(9)-3.808?(1)?Å].
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Antihaemorrhagic potentials of Fagonia cretica against Naja naja karachiensis (black Pakistan cobra) venom.
Nat. Prod. Res.
PUBLISHED: 11-01-2011
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Plants have been extensively used as a remedy for the treatment of snake bites. The aim of this study was to determine the antivenom potentials of methanolic extract from the aerial parts (leaves and twigs) of Fagonia cretica L. on a haemorrhage induced by venom from Naja naja karachiensis. The haemorrhagic response of venom was dose dependent from 0.1 to 4.0?µg per 1.5?µL phosphate buffer saline (PBS) on vitelline veins of fertilised hens eggs in their shells. The extract effectively eliminated and neutralised, in a dose-dependent manner, the haemorrhagic activity of snake venom. The minimum effective neutralising dose of F. cretica extract was found to be 15?µg per 1.5?µL PBS. The extract possesses potentials as haemorrhagic inhibitor against snake venom compared to the standard antiserum and various plants reported in the literature. This study also provides a scientific base for the use of F. cretica in traditional medicine for the treatment of snake bite.
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Metal ion affinity-based biomolecular recognition and conjugation inside synthetic polymer nanopores modified with iron-terpyridine complexes.
J. Am. Chem. Soc.
PUBLISHED: 10-10-2011
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Here we demonstrate a novel biosensing platform for the detection of lactoferrin (LFN) via metal-organic frameworks, in which the metal ions have accessible free coordination sites for binding, inside the single conical nanopores fabricated in polymeric membrane. First, monolayer of amine-terminated terpyridine (metal-chelating ligand) is covalently immobilized on the inner walls of the nanopore via carbodiimide coupling chemistry. Second, iron-terpyridine (iron-terPy) complexes are obtained by treating the terpyridine modified-nanopores with ferrous sulfate solution. The immobilized iron-terPy complexes can be used as recognition elements to fabricate biosensing nanodevice. The working principle of the proposed biosensor is based on specific noncovalent interactions between LFN and chelated metal ions in the immobilized terpyridine monolayer, leading to the selective detection of analyte protein. In addition, control experiments proved that the designed biosensor exhibits excellent biospecificity and nonfouling properties. Furthermore, complementary experiments are conducted with multipore membranes containing an array of cylindrical nanopores. We demonstrate that in the presence of LFN in the feed solution, permeation of methyl viologen (MV(2+)) and 1,5-naphthalenedisulphate (NDS(2-)) is drastically suppressed across the iron-terPy modified membranes. On the basis of these findings, we envision that apart from conventional ligand-receptor interactions, the designing and immobilization of alternative functional ligands inside the synthetic nanopores would extend this method for the construction of new metal ion affinity-based biomimetic systems for the specific binding and recognition of other biomolecules.
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Fabrication of potential macromolecular prodrugs of aspirin and diclofenac with dextran.
Pak J Pharm Sci
PUBLISHED: 10-01-2011
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Aspirin and diclofenac conjugates with dextran were synthesized as potential macromolecular prodrugs under homogeneous reaction conditions by using 4-methyl-benzenesulfonyl chloride as an acylating agent in the presence of triethylamine as a base. Highly pure conjugates with good yields were synthesized by this acylation method. All of the products were found soluble in aqueous medium as well as in dimethylsulfoxide and N,N-dimethylacetamide. The UV/Vis spectrophotometry has indicated the incorporation of drugs in conjugates and extent of substitution of drug onto dextran polymer. Covalent attachment of the drug onto the drug carrier polymer (dextran) was verified by (1)H NMR and Fourier transform infrared (FTIR) spectroscopic analysis. The prodrugs were analysed by powder X-ray diffraction (XRD) measurements. Phase changes were noticed by powder XRD for all macromolecular prodrugs indicating the change of state of matter towards more crystallinity. Therefore, fabricated macromolecular prodrugs are potential candidates to show better pharmacokinetic profile. All of the products were thoroughly characterized by using different spectroscopic techniques.
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Engineered multifunctional nanotools for biological applications.
Methods Mol. Biol.
PUBLISHED: 09-28-2011
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Smart multifunctional magnetic nanoparticles are popular candidates for several biological applications owing to their intrinsic magnetic property and diverse applications that range from rare protein separation and biomedical utilization to cancer therapy and diagnostics. A universal protocol, for the development of such nanocarriers, is highly desirable for scientists with different backgrounds so that custom-made multifunctional nanoparticles can be developed to address their needs, among which are the superparamagnetic iron oxide and manganese oxide nanoparticles that are synthesized through high temperature decomposition reactions. However, an interface is needed to present these inorganic materials to biomolecules to enhance their application for different biological use. This compatibility is achieved by introducing a class of multifunctional copolymers. Magnetic nanoparticles are elaborately decorated with copolymers that carry three principle functionalities as follows: (1) dopamine moieties for surface anchorage of metal oxides; (2) dyes for optical detection; and (3) a large variety of functional molecules such as amines or carboxylates for conjugation of various biomolecules (i.e., proteins, nucleic acids, enzymes, etc.). These copolymers, in combination with nanoparticles, serve as a tool box that results in engineered nanotools with customized modifications and functionalities for applications in fields ranging from proteomics -bioseparation to tumor therapy.
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?C1 of chili leaf curl betasatellite is a pathogenicity determinant.
Virol. J.
PUBLISHED: 09-12-2011
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Cotton leaf curl disease in the Indian subcontinent is associated with several distinct begomoviruses that interact with a disease-specific DNA satellite named Cotton leaf curl Multan betasatellite (CLCuMB). However, we have recently reported that Chili leaf curl betasatellite (ChLCB) is also occasionally found associated with the disease in Pakistan. The question as to whether ChLCB contributes to the development of disease symptoms such as leaf curling and enations remain to be answered. We have previously shown that the expression of ?C1 of CLCuMB develops all symptoms of cotton leaf curl disease in Nicotiana benthamiana when expressed from PVX vector.
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