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Examination of Imprinting Process with Molsidomine as a Template  [PDF]
Piotr Luliński,Dorota Maciejewska
Molecules , 2009, DOI: 10.3390/molecules14062212
Abstract: Eight different functional monomers were used with ethylene glycol dimethacrylate as a cross-linker and molsidomine as a template to obtain molecularly imprinted polymers (MIPs). Non-covalent interactions between molsidomine and each functional monomer in DMSO prior to thermal bulk polymerization were utilized. On the basis of calculated imprinting factors, MIP prepared with N,N’-diallyltartaramide was chosen for further investigations. Examination of interactions in the prepolymerization complex between molsidomine and N,N’-diallyltartaramide was performed using the Job method. The absorbance of isomolar solutions reaching a maximum for the molar ratio of template to monomer equal to 1:4. Scatchard analysis was used for estimation of the dissociation constants and the maximum amounts of binding sites. The polymer based on N,N’-diallyltartaramide has two classes of heterogeneous binding sites characterized by two values of Kd and two Bmax: Kd(1) = 1.17 mM-1 and Bmax(1) = 0.8 μmol/mg for the higher affinity binding sites, and Kd(2) = 200 μM-1 and Bmax(2) = 2.05 μmol/mg for the lower affinity binding sites. Furthermore, effects of pH and organic solvent on binding properties of MIP and NIP were investigated, together with release of molsidomine from both MIP and NIP.
Dopamine-Imprinted Polymers: Template-Monomer Interactions, Analysis of Template Removal and Application to Solid Phase Extraction  [PDF]
Piotr Luliński,Dorota Maciejewska,Magdalena Bamburowicz-Klimkowska,Miros?aw Szutowski
Molecules , 2007, DOI: 10.3390/12112434
Abstract: A dopamine-imprinted polymer (MIP) was prepared in aqueous methanolsolution at 60oC by free-radical cross-linking polymerization of methacrylic acid in thepresence of ethylene glycol dimethacrylate as the cross-linker and dopamine hydrochlorideas the template molecule. Its ability to isolate dopamine was evaluated as the basis of asolid phase extraction procedure and compared with that of a non-imprinted polymer(NIP). The binding of dopamine was 84.1% and 29.1% for MIP and NIP, respectively.Various reported post-polymerization treatments to reduce template bleeding wereexamined. In our case the lowest bleeding was achieved after applying a combinedprocedure: continuous extraction in a Soxhlet apparatus (CE), followed by microwave-assisted extraction (ME) to a level of 0.061 μg/mL. A simplified model of the template-monomer complexes allowed rationalization of monomer choice based on the heats ofcomplex formation at a PM3 level of theory.
Imprinting in plants
Jose Gutierrez-Marcos
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0418-6
Abstract: Genomic imprinting leads to the differential expression of parental alleles after fertilization. Imprinting appears to have evolved independently in mammals and flowering plants to regulate the development of nutrient-transfer placental tissues. In addition, the regulation of imprinting in both mammals and flowering plants involves changes in DNA methylation and histone methylation, thus suggesting that the epigenetic signals that regulate imprinting have been co-opted in these distantly related species.
Genomic imprinting and human chromosome 15
Biological Research , 2001, DOI: 10.4067/S0716-97602001000200020
Abstract: genomic imprinting is a reversible phenomenon that affects the expression of genes depending on their parental origin. the best characterized human disorders resulting from an alteration of the imprinting process are angelman and prader-willi syndromes. they are due to the lack of active maternal or paternal genes, respectively, from chromosome region 15q11q13. most cases arise via interstitial deletions. we review evidence that other common cytogenetic alterations of this region, interstitial and supernumerary duplications, could be the reciprocal products of the deletions and are also affected by the imprinting phenomenon, given the predominance of maternally-derived duplications in patients ascertained due to developmental delays or autistic features.
Genomic imprinting and human chromosome 15  [cached]
Biological Research , 2001,
Abstract: Genomic imprinting is a reversible phenomenon that affects the expression of genes depending on their parental origin. The best characterized human disorders resulting from an alteration of the imprinting process are Angelman and Prader-Willi syndromes. They are due to the lack of active maternal or paternal genes, respectively, from chromosome region 15q11q13. Most cases arise via interstitial deletions. We review evidence that other common cytogenetic alterations of this region, interstitial and supernumerary duplications, could be the reciprocal products of the deletions and are also affected by the imprinting phenomenon, given the predominance of maternally-derived duplications in patients ascertained due to developmental delays or autistic features.
A Novel Biometric Technique Benchmark Analysis For Selection Of Best Biometric Modality And Template Generation Method
Sharanabasappa Raikoti,Dr Sanjaypande M. B.2
International Journal of Biometric and Bioinformatics , 2011,
Abstract: A biometric security is a technique by means of which digital contents are protected by acryptographic key generated from the biometric features of a person like Retina, Iris, Fingerprint,Face, Voice and so on. Normally the digital contents like documents are protected by acryptographic key generated from a unique password. The process in irreversible, i.e the key canbe generated from the password but not the vice versa. Passwords are relatively easy to hack asmost of the users keep their personal information like date of birth as password and alsopassword length has a limit as human beings cannot remember a password of significantly largelength. Hence guessing the password of a user, whose significant information is available, iseasier. Therefore off late lot of emphasis has been given to biometric features. Biometric featuresof no two people are same. For example the finger prints or the face of any two people differ.Hence if a template (alphanumeric or binary representation of features from a biometric data) isselected for the key generation than cracking them for accessing information becomessignificantly difficult. But as with every advantage comes certain limitations also. The keys are nottime invariant. Templates tends to change based on the data acquisition, or with time. Forexample the finger prints or palm prints changes with ages. Iris, retina and face features changeswith change in light intensity during the acquisition phase. Fingerprint features changes withchange in the orientation of the finger while scanning. In a classic authentication problem, suchvariability’s can be easily dealt with by keeping a threshold for the acceptance of the features.Such acceptance threshold is not applicable for the case of biometric templates. Even slightest ofthe variability in the templates changes the generated key, therefore causing a high falserejection rate. Hence in this work we analyze the most accepted biometric features andtechniques for key generation and propose the most invariable technique in terms of dataacquisition invariability. The work analyzes Iris, Face, Fingerprint and Palm prints for analysis ofthe biometric template generation and key generation form the templates. Further a uniquebenchmark analysis technique is proposed for quantifying the quality of a biometric model orfeatures.
Synthesis and Theoretical Study of Molecularly Imprinted Nanospheres for Recognition of Tocopherols  [PDF]
Theeraphon Piacham,Chanin Nantasenamat,Thummaruk Suksrichavalit,Charoenchai Puttipanyalears,Tippawan Pissawong,Supanee Maneewas,Chartchalerm Isarankura-Na-Ayudhya,Virapong Prachayasittikul
Molecules , 2009, DOI: 10.3390/molecules14082985
Abstract: Molecular imprinting is a technology that facilitates the production of artificial receptors toward compounds of interest. The molecularly imprinted polymers act as artificial antibodies, artificial receptors, or artificial enzymes with the added benefit over their biological counterparts of being highly durable. In this study, we prepared molecularly imprinted polymers for the purpose of binding specifically to tocopherol (vitamin E) and its derivative, tocopherol acetate. Binding of the imprinted polymers to the template was found to be two times greater than that of the control, non-imprinted polymers, when using only 10 mg of polymers. Optimization of the rebinding solvent indicated that ethanol-water at a molar ratio of 6:4 (v/v) was the best solvent system as it enhanced the rebinding performance of the imprinted polymers toward both tocopherol and tocopherol acetate with a binding capacity of approximately 2 mg/g of polymer. Furthermore, imprinted nanospheres against tocopherol was successfully prepared by precipitation polymerization with ethanol-water at a molar ratio of 8:2 (v/v) as the optimal rebinding solvent. Computer simulation was also performed to provide mechanistic insights on the binding mode of template-monomer complexes. Such polymers show high potential for industrial and medical applications, particularly for selective separation of tocopherol and derivatives.
Preparation of Molecularly Imprinted Polymer for Sulpiride and Its Adsorption Characteristics

ZHANG Wei,SHE Xu-hui,FAN Hua-jun,JIANG Zi-tao,WU Kun-hong,WANG Li-ping,

过程工程学报 , 2012,
Abstract: Using sulpiride(SUL) as template,methacrylic acid(MAA) as function monomer,and ethyleneglycol dimethacrylate(EDMA) as cross linker,a molecularly imprinted polymer(MIP) was synthesized by bulk polymerization.Static adsorption and isothermal adsorption experiments were performed to study the influential factors on adsorption properties of the MIP to SUL by UV,FT-IR and SEM analysis.Adsorption mechanism of the MIP was also analyzed.The results showed that its best imprinting effect on SUL was observed when the volume of acetonitrile was 6 mL,molar ratio of SUL to MAA 1 to 4,and methanol-acetic acid(9:1,φ) used as eluting agent.The MIP offered uniform,loose and porous structure with 79.12 μmol/g of maximum adsorption capacity and 3.76 of imprinted factor for SUL.The main recognition sites of MIP were cavities caused by three types of amino groups on amide,benzsulfamide and 1-methylpyrrolidine in molecular structure.The MIP had better specific adsorption and exhibited good recognition and selectivity to SUL and its analogues such as amisulpride and tiapride.Their specific adsorption rates were respectively 68.35%,66.72% and 58.8%.Thus,the MIP could be used in separation and analysis for SUL drugs.
Preparation and Optimization of a Palladium Ion Imprinted Polymer

- , 2018, DOI: 10.13209/j.0479-8023.2018.015
Abstract: 摘要 采用沉淀聚合法, 以PdCl42?为模板, 以4-乙烯基吡啶(4-VP)、2-烯丙巯基烟酸(ANA)、2-乙酸胺基丙烯酸(AAA)为功能单体, 加入交联剂二甲基丙烯酸乙二醇酯(EGDMA)、引发剂偶氮二异丁腈(AIBN)和致孔剂甲醇, 制备钯离子印迹聚合物。通过添加不同种类、用量的功能单体和不同用量的交联剂, 探究不同制备条件对钯离子印迹聚合物制备效果的影响。优化结果表明, 与ANA和AAA功能单体对比, 4-VP和PdCl42–能形成4:1的稳定配合物, 结合常数最大, 印迹效果最好, 是 3 种功能单体中用于制备钯离子印迹聚合物的最佳选择。吸附试验结果进一步表明, 按照模板、功能单体、交联剂用量比例为1:4:40制备的钯离子印迹聚合物对Pd(II)的吸附量最大, 为5.042 mg/g。
Abstract Palladium (II) ion imprinted polymers (IIP) were prepared by precipitation polymerization method using PdCl42– as template, 4-vinylpridine(4-VP), 2-(allylthio)nicotinic acid (ANA), 2-Acetamidoacrylic acid (AAA) as functional monomer, respectively. In the polymerization method, the polymerization mixture included ethylene glycoldimethacrylate (EGDMA, cross-linking monomer), 2,2-azobisisobutyronitrile (AIBN, initiator) and methanol (porogen). The effects of different preparation conditions on the preparation of palladium ion imprinted polymers were investigated by the type of functional monomers, the dosage of functional monomers and crosslinking agents. The optimization results showed that compared with ANA and AAA, 4 -VP could form a stable complex with PdCl42– in the molar ratio of 4:1 with the largest binding constant and the best imprinting effect, which was the best choice for the synthesis of palladium (II) ion imprinted polymer. Furthermore, the adsorption experiment proved the adsorption capacity of 4-VP on its corresponding imprinted polymers in accordance to the ratio of template, functional monomer and cross-linking monomer as 1:4:40 reached a maximum of 5.042 mg/g.
The Importance of Imprinting in the Human Placenta  [PDF]
Jennifer M. Frost ,Gudrun E. Moore
PLOS Genetics , 2010, DOI: 10.1371/journal.pgen.1001015
Abstract: As a field of study, genomic imprinting has grown rapidly in the last 20 years, with a growing figure of around 100 imprinted genes known in the mouse and approximately 50 in the human. The imprinted expression of genes may be transient and highly tissue-specific, and there are potentially hundreds of other, as yet undiscovered, imprinted transcripts. The placenta is notable amongst mammalian organs for its high and prolific expression of imprinted genes. This review discusses the development of the human placenta and focuses on the function of imprinting in this organ. Imprinting is potentially a mechanism to balance parental resource allocation and it plays an important role in growth. The placenta, as the interface between mother and fetus, is central to prenatal growth control. The expression of genes subject to parental allelic expression bias has, over the years, been shown to be essential for the normal development and physiology of the placenta. In this review we also discuss the significance of genes that lack conservation of imprinting between mice and humans, genes whose imprinted expression is often placental-specific. Finally, we illustrate the importance of imprinting in the postnatal human in terms of several human imprinting disorders, with consideration of the brain as a key organ for imprinted gene expression after birth.
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