Mobilome and genetic modification of bifidobacteria.

Science.gov (United States)

Guglielmetti, S; Mayo, B; Álvarez-Martín, P

2013-06-01

Until recently, proper development of molecular studies in Bifidobacterium species has been hampered by growth difficulties, because of their exigent nutritive requirements, oxygen sensitivity and lack of efficient genetic tools. These studies, however, are critical to uncover the cross-talk between bifidobacteria and their hosts' cells and to prove unequivocally the supposed beneficial effects provided through the endogenous bifidobacterial populations or after ingestion as probiotics. The genome sequencing projects of different bifidobacterial strains have provided a wealth of genetic data that will be of much help in deciphering the molecular basis of the physiological properties of bifidobacteria. To this end, the purposeful development of stable cloning and expression vectors based on robust replicons - either from temperate phages or resident plasmids - is still needed. This review addresses the current knowledge on the mobile genetic elements of bifidobacteria (prophages, plasmids and transposons) and summarises the different types of vectors already available, together with the transformation procedures for introducing DNA into the cells. It also covers recent molecular studies performed with such vectors and incipient results on the genetic modification of these organisms, establishing the basis that would allow the use of bifidobacteria for future biotechnological applications.

Repetitive sequences and epigenetic modification: inseparable partners play important roles in the evolution of plant sex chromosomes.

Science.gov (United States)

Li, Shu-Fen; Zhang, Guo-Jun; Yuan, Jin-Hong; Deng, Chuan-Liang; Gao, Wu-Jun

2016-05-01

The present review discusses the roles of repetitive sequences played in plant sex chromosome evolution, and highlights epigenetic modification as potential mechanism of repetitive sequences involved in sex chromosome evolution. Sex determination in plants is mostly based on sex chromosomes. Classic theory proposes that sex chromosomes evolve from a specific pair of autosomes with emergence of a sex-determining gene(s). Subsequently, the newly formed sex chromosomes stop recombination in a small region around the sex-determining locus, and over time, the non-recombining region expands to almost all parts of the sex chromosomes. Accumulation of repetitive sequences, mostly transposable elements and tandem repeats, is a conspicuous feature of the non-recombining region of the Y chromosome, even in primitive one. Repetitive sequences may play multiple roles in sex chromosome evolution, such as triggering heterochromatization and causing recombination suppression, leading to structural and morphological differentiation of sex chromosomes, and promoting Y chromosome degeneration and X chromosome dosage compensation. In this article, we review the current status of this field, and based on preliminary evidence, we posit that repetitive sequences are involved in sex chromosome evolution probably via epigenetic modification, such as DNA and histone methylation, with small interfering RNAs as the mediator.

Genetic Modification in Dedicated Bioenergy Crops and Strategies for Gene Confinement

Science.gov (United States)

Genetic modification of dedicated bioenergy crops is in its infancy; however, there are numerous advantages to the use of these tools to improve crops used for biofuels. Potential improved traits through genetic engineering (GE) include herbicide resistance, pest, drought, cold and salt tolerance, l...

GENETIC CONTROL OF RESTRICTION AND MODIFICATION IN ESCHERICHIA COLI1

Science.gov (United States)

Boyer, Herbert

1964-01-01

Boyer, Herbert (Yale University, New Haven, Conn.). Genetic control of restriction and modification in Escherichia coli. J. Bacteriol. 88:1652–1660. 1964.—Bacterial crosses with K-12 strains of Escherichia coli as Hfr donors (Hfr Hayes, Hfr Cavalli, and Hfr P4X-6) and B/r strains of E. coli as F− recipients were found to differ from crosses between K-12 Hfr donors and K-12 F− recipients in two ways: (i) recombinants (leu, pro, lac, and gal) did not appear at discrete time intervals but did appear simultaneously 30 min after matings were initiated, and (ii) the linkage of unselected markers to selected markers was reduced. Integration of a genetic region linked to the threonine locus of K-12 into the B/r genome resulted in a hybrid which no longer gave anomalous results in conjugation experiments. A similar region of the B strain was introduced into the K-12 strain, which then behaved as a typical B F− recipient. These observations are interpreted as the manifestation of host-controlled modification and restriction on the E. coli chromosome. This was verified by experiments on the restriction and modification of the bacteriophage lambda, F-lac, F-gal, and sex-factor, F1. It was found that the genetic region that controlled the mating responses of the K-12 and B/r strains also controlled the modification and restriction properties of these two strains. The genes responsible for the restricting and modifying properties of the K-12 and B strains of E. coli were found to be allelic, linked to each other, and linked to the threonine locus. PMID:14240953

Potential benefits of genetic modification (GM) technology for food ...

African Journals Online (AJOL)

We assessed the perception of farmers towards potential adoption of genetic modification (GM) technology for improving health, food security and agricultural productivity using a semi-structured interview. A total sample of 54 small-scale farmers participated in 6 focus group meetings (FGMs) and 23 in-depth interviews at ...

An environmental-economic assessment of genetic modification of agricultural crops

NARCIS (Netherlands)

van den Bergh, J.C.J.M.; Holley, J.M.

2002-01-01

The advantages and disadvantages of genetic modification of organisms in agriculture are reviewed. These relate to the environment, human health, socio-economic effects, population growth, and differential consequences for developed and developing countries. An overall evaluation requires that

Explaining consumer attitudes to genetic modification in food production

DEFF Research Database (Denmark)

Bredahl, Lone

for explaining consumer attitudes to genetic modification in food production which builds on modern cognitive psychology and multi-attribute attitude theory. In addition, the paper introduces the empirical research which is undertaken at present to validate and estimate the parameters of the model by means......Consumers have not had many possibilities yet for seeking out, buying and consuming genetically modified food products. However, for various reasons consumer attitude formation with regard to these products is likely to be complex and closely related to personal values. The paper presents a model...

Genetic modification of lymphocytes by retrovirus-based vectors.

Science.gov (United States)

Suerth, Julia D; Schambach, Axel; Baum, Christopher

2012-10-01

The genetic modification of lymphocytes is an important topic in the emerging field of gene therapy. Many clinical trials targeting immunodeficiency syndromes or cancer have shown therapeutic benefit; further applications address inflammatory and infectious disorders. Retroviral vector development requires a detailed understanding of the interactions with the host. Most researchers have used simple gammaretroviral vectors to modify lymphocytes, either directly or via hematopoietic stem and progenitor cells. Lentiviral, spumaviral (foamyviral) and alpharetroviral vectors were designed to reduce the necessity for cell stimulation and to utilize potentially safer integration properties. Novel surface modifications (pseudotyping) and transgenes, built using synthetic components, expand the retroviral toolbox, altogether promising increased specificity and potency. Product consistency will be an important criterion for routine clinical use. Copyright © 2012. Published by Elsevier Ltd.

Methods for genetic modification of megakaryocytes and platelets.

Science.gov (United States)

Pendaries, Caroline; Watson, Stephen P; Spalton, Jennifer C

2007-09-01

During recent decades there have been major advances in the fields of thrombosis and haemostasis, in part through development of powerful molecular and genetic technologies. Nevertheless, genetic modification of megakaryocytes and generation of mutant platelets in vitro remains a highly specialized area of research. Developments are hampered by the low frequency of megakaryocytes and their progenitors, a poor efficiency of transfection and a lack of understanding with regard to the mechanism by which megakaryocytes release platelets. Current methods used in the generation of genetically modified megakaryocytes and platelets include mutant mouse models, cell line studies and use of viruses to transform primary megakaryocytes or haematopoietic precursor cells. This review summarizes the advantages, limitations and technical challenges of such methods, with a particular focus on recent successes and advances in this rapidly progressing field including the potential for use in gene therapy for treatment of patients with platelet disorders.

Genetic modification and its impact on industry structure and performance

NARCIS (Netherlands)

Vlaar, P.W.L.; van Beek, P.; Visser, R.G.F.

2007-01-01

Genetic modification has led to fierce debates around the world. Nevertheless, scientific evidence for its potential effects on the structure and performance of industries has hitherto remained rather meagre. In this article, we take some preliminary steps towards closing this gap by exploring the

Consumer perception of food products involving genetic modification: Results from a qualitative study in four Nordic countries

DEFF Research Database (Denmark)

Grunert, Klaus G.; Lähteenmäki, Liisa; Nielsen, Niels Asger

2000-01-01

1. The present study addresses consumer acceptance of food products involving the use of different applications of genetic modification in four Nordic countries. Three food products were used as examples: hard cheese, hard candy, and salmon. Three types of applications of genetic modification were...... in the final product has a clear impact on consumer acceptance. When the GM material is present and viable/able to function, acceptance is lowest. 5. The type of application of genetic modification has an impact on consumer acceptance as well, but it differs across products. Still, there is a clear tendency...

Characterization of unknown genetic modifications using high throughput sequencing and computational subtraction

Directory of Open Access Journals (Sweden)

Butenko Melinka A

2009-10-01

Full Text Available Abstract Background When generating a genetically modified organism (GMO, the primary goal is to give a target organism one or several novel traits by using biotechnology techniques. A GMO will differ from its parental strain in that its pool of transcripts will be altered. Currently, there are no methods that are reliably able to determine if an organism has been genetically altered if the nature of the modification is unknown. Results We show that the concept of computational subtraction can be used to identify transgenic cDNA sequences from genetically modified plants. Our datasets include 454-type sequences from a transgenic line of Arabidopsis thaliana and published EST datasets from commercially relevant species (rice and papaya. Conclusion We believe that computational subtraction represents a powerful new strategy for determining if an organism has been genetically modified as well as to define the nature of the modification. Fewer assumptions have to be made compared to methods currently in use and this is an advantage particularly when working with unknown GMOs.

A scalable pipeline for highly effective genetic modification of a malaria parasite

KAUST Repository

Pfander, Claudia

2011-10-23

In malaria parasites, the systematic experimental validation of drug and vaccine targets by reverse genetics is constrained by the inefficiency of homologous recombination and by the difficulty of manipulating adenine and thymine (A+T)-rich DNA of most Plasmodium species in Escherichia coli. We overcame these roadblocks by creating a high-integrity library of Plasmodium berghei genomic DNA (>77% A+T content) in a bacteriophage N15-based vector that can be modified efficiently using the lambda Red method of recombineering. We built a pipeline for generating P. berghei genetic modification vectors at genome scale in serial liquid cultures on 96-well plates. Vectors have long homology arms, which increase recombination frequency up to tenfold over conventional designs. The feasibility of efficient genetic modification at scale will stimulate collaborative, genome-wide knockout and tagging programs for P. berghei. © 2011 Nature America, Inc. All rights reserved.

A scalable pipeline for highly effective genetic modification of a malaria parasite

KAUST Repository

Pfander, Claudia; Anar, Burcu; Schwach, Frank; Otto, Thomas D.; Brochet, Mathieu; Volkmann, Katrin; Quail, Michael A.; Pain, Arnab; Rosen, Barry; Skarnes, William; Rayner, Julian C.; Billker, Oliver

2011-01-01

In malaria parasites, the systematic experimental validation of drug and vaccine targets by reverse genetics is constrained by the inefficiency of homologous recombination and by the difficulty of manipulating adenine and thymine (A+T)-rich DNA of most Plasmodium species in Escherichia coli. We overcame these roadblocks by creating a high-integrity library of Plasmodium berghei genomic DNA (>77% A+T content) in a bacteriophage N15-based vector that can be modified efficiently using the lambda Red method of recombineering. We built a pipeline for generating P. berghei genetic modification vectors at genome scale in serial liquid cultures on 96-well plates. Vectors have long homology arms, which increase recombination frequency up to tenfold over conventional designs. The feasibility of efficient genetic modification at scale will stimulate collaborative, genome-wide knockout and tagging programs for P. berghei. © 2011 Nature America, Inc. All rights reserved.

Genetic Modification of the Lung Directed Toward Treatment of Human Disease.

Science.gov (United States)

Sondhi, Dolan; Stiles, Katie M; De, Bishnu P; Crystal, Ronald G

2017-01-01

Genetic modification therapy is a promising therapeutic strategy for many diseases of the lung intractable to other treatments. Lung gene therapy has been the subject of numerous preclinical animal experiments and human clinical trials, for targets including genetic diseases such as cystic fibrosis and α1-antitrypsin deficiency, complex disorders such as asthma, allergy, and lung cancer, infections such as respiratory syncytial virus (RSV) and Pseudomonas, as well as pulmonary arterial hypertension, transplant rejection, and lung injury. A variety of viral and non-viral vectors have been employed to overcome the many physical barriers to gene transfer imposed by lung anatomy and natural defenses. Beyond the treatment of lung diseases, the lung has the potential to be used as a metabolic factory for generating proteins for delivery to the circulation for treatment of systemic diseases. Although much has been learned through a myriad of experiments about the development of genetic modification of the lung, more work is still needed to improve the delivery vehicles and to overcome challenges such as entry barriers, persistent expression, specific cell targeting, and circumventing host anti-vector responses.

Quadratic genetic modifications: a streamlined route to cosmological simulations with controlled merger history

Science.gov (United States)

Rey, Martin P.; Pontzen, Andrew

2018-02-01

Recent work has studied the interplay between a galaxy's history and its observable properties using `genetically modified' cosmological zoom simulations. The approach systematically generates alternative histories for a halo, while keeping its cosmological environment fixed. Applications to date altered linear properties of the initial conditions, such as the mean overdensity of specified regions; we extend the formulation to include quadratic features, such as local variance, that determines the overall importance of smooth accretion relative to mergers in a galaxy's history. We introduce an efficient algorithm for this new class of modification and demonstrate its ability to control the variance of a region in a one-dimensional toy model. Outcomes of this work are twofold: (i) a clarification of the formulation of genetic modifications and (ii) a proof of concept for quadratic modifications leading the way to a forthcoming implementation in cosmological simulations.

Enzyme Technology of Peroxidases: Immobilization, Chemical and Genetic Modification

Science.gov (United States)

Longoria, Adriana; Tinoco, Raunel; Torres, Eduardo

An overview of enzyme technology applied to peroxidases is made. Immobilization on organic, inorganic, and hybrid supports; chemical modification of amino acids and heme group; and genetic modification by site-directed and random mutagenesis are included. Different strategies that were carried out to improve peroxidase performance in terms of stability, selectivity, and catalytic activity are analyzed. Immobilization of peroxidases on inorganic and organic materials enhances the tolerance of peroxidases toward the conditions normally found in many industrial processes, such as the presence of an organic solvent and high temperature. In addition, it is shown that immobilization helps to increase the Total Turnover Number at levels high enough to justify the use of a peroxidase-based biocatalyst in a synthesis process. Chemical modification of peroxidases produces modified enzymes with higher thermostability and wider substrate variability. Finally, through mutagenesis approaches, it is possible to produce modified peroxidases capable of oxidizing nonnatural substrates with high catalytic activity and affinity.

What's in a name? Y chromosomes, surnames and the genetic genealogy revolution.

Science.gov (United States)

King, Turi E; Jobling, Mark A

2009-08-01

Heritable surnames are highly diverse cultural markers of coancestry in human populations. A patrilineal surname is inherited in the same way as the non-recombining region of the Y chromosome and there should, therefore, be a correlation between the two. Studies of Y haplotypes within surnames, mostly of the British Isles, reveal high levels of coancestry among surname cohorts and the influence of confounding factors, including multiple founders for names, non-paternities and genetic drift. Combining molecular genetics and surname analysis illuminates population structure and history, has potential applications in forensic studies and, in the form of 'genetic genealogy', is an area of rapidly growing interest for the public.

Redirecting adenovirus tropism by genetic, chemical, and mechanical modification of the adenovirus surface for cancer gene therapy.

Science.gov (United States)

Yoon, A-Rum; Hong, Jinwoo; Kim, Sung Wan; Yun, Chae-Ok

2016-06-01

Despite remarkable advancements, clinical evaluations of adenovirus (Ad)-mediated cancer gene therapies have highlighted the need for improved delivery and targeting. Genetic modification of Ad capsid proteins has been extensively attempted. Although genetic modification enhances the therapeutic potential of Ad, it is difficult to successfully incorporate extraneous moieties into the capsid and the engineering process is laborious. Recently, chemical modification of the Ad surface with nanomaterials and targeting moieties has been found to enhance Ad internalization into the target by both passive and active mechanisms. Alternatively, external stimulus-mediated targeting can result in selective accumulation of Ad in the tumor and prevent dissemination of Ad into surrounding nontarget tissues. In the present review, we discuss various genetic, chemical, and mechanical engineering strategies for overcoming the challenges that hinder the therapeutic efficacy of Ad-based approaches. Surface modification of Ad by genetic, chemical, or mechanical engineering strategies enables Ad to overcome the shortcomings of conventional Ad and enhances delivery efficiency through distinct and unique mechanisms that unmodified Ad cannot mimic. However, although the therapeutic potential of Ad-mediated gene therapy has been enhanced by various surface modification strategies, each strategy still possesses innate limitations that must be addressed, requiring innovative ideas and designs.

Genetic modification: a tool for enhancing cellulase secretion

Directory of Open Access Journals (Sweden)

Anusuiya Singh

2017-06-01

Full Text Available Lignocellulosic (LC biomass is abundantly available as a low-cost resource on the Earth. LC conversion into energy carriers is the most accepted alternative energy production policy because it is non-competitor to food or feed. LC ethanol has brought cellulases to the forefront which was otherwise lost in oblivion during last decades. LC biomass can be converted into value added products or into sugars by various routes, e.g., thermo-chemical, chemical, or biological methods. Biological route via enzymes is one of the most eco-friendly and feasible method. Both fungi and bacteria are known to degrade biomass. Fungi have been greatly exploited for cellulase production due to their inherent properties of secreting extracellular cellulase. These microorganisms are known as cellulase producers for many decades, however, to bring the enzymatic biomass conversion to an economically feasible status, extensive research efforts have been made in last decade to enhance cellulase titers. Mutations and genetic interventions along with bioprocess development have played a very important role for enhancing cellulase production. This review will present a critical overview of the on-going research towards improving cellulase production for biofuel industry via genetic modification, which will include mutation and genetic engineering employed to exert changes at genetic level in microorganisms.

Immune modulation by genetic modification of dendritic cells with lentiviral vectors.

Science.gov (United States)

Liechtenstein, Therese; Perez-Janices, Noemi; Bricogne, Christopher; Lanna, Alessio; Dufait, Inès; Goyvaerts, Cleo; Laranga, Roberta; Padella, Antonella; Arce, Frederick; Baratchian, Mehdi; Ramirez, Natalia; Lopez, Natalia; Kochan, Grazyna; Blanco-Luquin, Idoia; Guerrero-Setas, David; Breckpot, Karine; Escors, David

2013-09-01

Our work over the past eight years has focused on the use of HIV-1 lentiviral vectors (lentivectors) for the genetic modification of dendritic cells (DCs) to control their functions in immune modulation. DCs are key professional antigen presenting cells which regulate the activity of most effector immune cells, including T, B and NK cells. Their genetic modification provides the means for the development of targeted therapies towards cancer and autoimmune disease. We have been modulating with lentivectors the activity of intracellular signalling pathways and co-stimulation during antigen presentation to T cells, to fine-tune the type and strength of the immune response. In the course of our research, we have found unexpected results such as the surprising immunosuppressive role of anti-viral signalling pathways, and the close link between negative co-stimulation in the immunological synapse and T cell receptor trafficking. Here we review our major findings and put them into context with other published work. Copyright © 2013 Elsevier B.V. All rights reserved.

Etikken bag kunstig selektion og genmodifikation af planter: The Ethics of Artificial Selection and Genetic Modification of Plants

OpenAIRE

Armstrong, Freya; Børgesen, Lasse Faber; Gierløff, Anders Pihl; Justesen, Louise; Niemeier, Sebastian; Sandgaard, Monica; Steensgaard, Ida Mathilde

2013-01-01

Artificial selection and genetic modification are both methods which are used to maximize crop profit. The recent years’ development in the genetic engineering sector has made it possible to transfer a specific trait from one organism to another. The development has caused a widespread ethical debate on the subject. This study examines two different cases based on genetic modification and artificial selection of plants respectively. The aim of this study is to determine, which ethics particip...

Consumer perceptions of food products involving genetic modification

DEFF Research Database (Denmark)

Grunert, Klaus G.; Lähteenmäki, L.; Nielsen, Niels Asger

2001-01-01

Product descriptions of cheese, candy and salmon products were presented to samples of respondents in four Nordic countries. The descriptions represented various applications of genetic modification (GM), varied along a "distance" dimension and a "what is modified" dimension, and were presented...... along with a conventionally produced product. Respondents ranked the products according to preference, and their perceptions were ascertained by the laddering method. Results indicate that respondents regard "non-GM" as a value in itself, and associate the use of GM with a host of negative consequences...... were product specific....

Genetic control of yeast cell radiosensitivity modification by oxygen and hypoxic sensitizers

International Nuclear Information System (INIS)

Zhuranovskaya, G.P.; Petin, V.G.

1984-01-01

Diploid yeast cells Saccharomyces cerevisiae ''of the wild type'', individual mutants, homozygous in rad 2 and rad 54 and double mutants, containing both these loci in homozygous state are considered to prove genetic determination of radiosensitivity modification of hypoxic cells by oxygen and electron acceptor compounds previously demonstrated on yeast cells of other genotypes. It is shown that both ''oxygen effect'' and the effect of hypoxic sensitizers depend on the activity of repair systems. The possible mechanism of participation of post-radiation restoration processes in the modification of cell radiosensitivity, is discussed

Genetic Control of the Secondary Modification of Deoxyribonucleic Acid in Escherichia coli1

Science.gov (United States)

Mamelak, Linda; Boyer, Herbert W.

1970-01-01

The wild-type restriction and modification alleles of Escherichia coli K-12 and B were found to have no measurable effect on the patterns of methylated bases in the deoxyribonucleic acid (DNA) of these strains. The genetic region controlling the methylation of cytosine in E. coli K-12 was mapped close to his, and the presence or absence of this gene in E. coli B or E. coli K had no effect on the restriction and modification properties of these strains. Thus, only a few of the methylated bases in the DNA of these strains are involved in host modification, and the biological role of the remainder remains obscure. PMID:4919756

Genetic modification of cells for transplantation.

Science.gov (United States)

Lai, Yi; Drobinskaya, Irina; Kolossov, Eugen; Chen, Chunguang; Linn, Thomas

2008-01-14

Progress in gene therapy has produced promising results that translate experimental research into clinical treatment. Gene modification has been extensively employed in cell transplantation. The main barrier is an effective gene delivery system. Several viral vectors were utilized in end-stage differentiated cells. Recently, successful applications were described with adenovirus-associated vectors. As an alternative, embryonic stem cell- and stem cell-like systems were established for generation of tissue-specified gene-modified cells. Owing to the feasibility for genetic manipulations and the self-renewing potency of these cells they can be used in a way enabling large-scale in vitro production. This approach offers the establishment of in vitro cell culture systems that will deliver sufficient amounts of highly purified, immunoautologous cells suitable for application in regenerative medicine. In this review, the current technology of gene delivery systems to cells is recapitulated and the latest developments for cell transplantation are discussed.

Genetic control of radiosensitivity modification of some yeast strons

International Nuclear Information System (INIS)

Petin, V.G.; Zhurakovskaya, I.P.

1982-01-01

The genetic determination of the relative biological effectiveness (RBE) of densely ionizing particles and cysteamine's radioprotective effect on irradiated cells, demonstrated earlier on yeast cells of different genotype, has been proved on diploid wild-type cells of Saccharomyces cerevisial yeasts, solitary mutants, homozygous with respect to rad 2 and rad 54, and double mutant containing both locuses in homozygous state. It is shown that RBE of α-particles and radioprotector's efficiency depend on repair system's activity. A possible mechanism of the participation of postirradiation recovery processes in the modification of cell radiosensitivity is discussed [ru

Attitudes Toward Genetic Modification Research: An Analysis of the Views of the Sputnik Generation.

Science.gov (United States)

Miller, Jon D.

1982-01-01

Utilizing data from the 1977 National Assessment of Educational Progress (NAEP) survey of young adults, summarizes attitudes toward genetic modification research and the demographic, educational, and occupational correlates of these attitudes. (Author/SK)

Progress in the molecular and genetic modification breeding of beef cattle in China.

Science.gov (United States)

Tong, Bin; Zhang, Li; Li, Guang-Peng

2017-11-20

The studies of beef cattle breeding in China have been greatly improved with the rapid development of the international beef cattle industrialization. The beef cattle breeding technologies have rapidly transformed from traditional breeding to molecular marker-assisted breeding, genomic selection and genetic modification breeding. Hundreds of candidate genes and molecular markers associated with growth, meat quality, reproduction performance and diseases resistance have been identified, and some of them have already been used in cattle breeding. Genes and molecular markers associated with growth and development are focused on the growth hormone, muscle regulatory factors, myostatin and insulin-like growth factors. Meat quality is mediated by fatty acid transport and deposition related signals, calpains and calpain system, muscle regulatory factors and muscle growth regulation pathways. Reproduction performance is regulated by GnRH-FSH-LH, growth differentiation factor 9, prolactin receptor and forkhead box protein O1. Disease resistance is modulated by the major histocompatibility complex gene family, toll-like receptors, mannose-binding lectin and interferon gene signals. In this review, we summarize the most recent progress in beef cattle breeding in marker-assisted selection, genome-wide selection and genetic modification breeding, aiming to provide a reference for further genetic breeding research of beef cattle in China.

Tailored HIV-1 vectors for genetic modification of primary human dendritic cells and monocytes.

Science.gov (United States)

Durand, Stéphanie; Nguyen, Xuan-Nhi; Turpin, Jocelyn; Cordeil, Stephanie; Nazaret, Nicolas; Croze, Séverine; Mahieux, Renaud; Lachuer, Joël; Legras-Lachuer, Catherine; Cimarelli, Andrea

2013-01-01

Monocyte-derived dendritic cells (MDDCs) play a key role in the regulation of the immune system and are the target of numerous gene therapy applications. The genetic modification of MDDCs is possible with human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LVs) but requires high viral doses to bypass their natural resistance to viral infection, and this in turn affects their physiological properties. To date, a single viral protein is able to counter this restrictive phenotype, Vpx, a protein derived from members of the HIV-2/simian immunodeficiency virus SM lineage that counters at least two restriction factors present in myeloid cells. By tagging Vpx with a short heterologous membrane-targeting domain, we have obtained HIV-1 LVs incorporating high levels of this protein (HIV-1-Src-Vpx). These vectors efficiently transduce differentiated MDDCs and monocytes either as previously purified populations or as populations within unsorted peripheral blood mononuclear cells (PBMCs). In addition, these vectors can be efficiently pseudotyped with receptor-specific envelopes, further restricting their cellular tropism almost uniquely to MDDCs. Compared to conventional HIV-1 LVs, these novel vectors allow for an efficient genetic modification of MDDCs and, more importantly, do not cause their maturation or affect their survival, which are unwanted side effects of the transduction process. This study describes HIV-1-Src-Vpx LVs as a novel potent tool for the genetic modification of differentiated MDDCs and of circulating monocyte precursors with strong potential for a wide range of gene therapy applications.

Genetic modification of stem cells for transplantation.

Science.gov (United States)

Phillips, M Ian; Tang, Yao Liang

2008-01-14

Gene modification of cells prior to their transplantation, especially stem cells, enhances their survival and increases their function in cell therapy. Like the Trojan horse, the gene-modified cell has to gain entrance inside the host's walls and survive and deliver its transgene products. Using cellular, molecular and gene manipulation techniques the transplanted cell can be protected in a hostile environment from immune rejection, inflammation, hypoxia and apoptosis. Genetic engineering to modify cells involves constructing modules of functional gene sequences. They can be simple reporter genes or complex cassettes with gene switches, cell specific promoters and multiple transgenes. We discuss methods to deliver and construct gene cassettes with viral and non-viral delivery, siRNA, and conditional Cre/Lox P. We review the current uses of gene-modified stem cells in cardiovascular disease, diabetes, neurological diseases, (including Parkinson's, Alzheimer's and spinal cord injury repair), bone defects, hemophilia, and cancer.

Mapping nonrecombining regions in barley using multicolor FISH

Czech Academy of Sciences Publication Activity Database

Karafiátová, Miroslava; Bartoš, Jan; Kopecký, David; Ma, L.; Sato, K.; Houben, A.; Stein, N.; Doležel, Jaroslav

2013-01-01

Roč. 21, č. 8 (2013), s. 739-751 ISSN 0967-3849 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional research plan: CEZ:AV0Z50380511 Keywords : cDNA * multicolor FISH * low-copy FISH Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.688, year: 2013

Genetic Modification of Human Pancreatic Progenitor Cells Through Modified mRNA.

Science.gov (United States)

Lu, Song; Chow, Christie C; Zhou, Junwei; Leung, Po Sing; Tsui, Stephen K; Lui, Kathy O

2016-01-01

In this chapter, we describe a highly efficient genetic modification strategy for human pancreatic progenitor cells using modified mRNA-encoding GFP and Neurogenin-3. The properties of modified mRNA offer an invaluable platform to drive protein expression, which has broad applicability in pathway regulation, directed differentiation, and lineage specification. This approach can also be used to regulate expression of other pivotal transcription factors during pancreas development and might have potential therapeutic values in regenerative medicine.

Reversibility of hepatocyte nuclear modifications in mice fed on genetically modified soybean

Directory of Open Access Journals (Sweden)

M Malatesta

2009-06-01

Full Text Available In the literature, the reports on the effects of a genetically modified (GM diet are scanty and heterogeneous; in particular, no direct evidence has so far been reported that GM food may affect human or animal health. Hepatocytes represent a suitable model for monitoring the effects of a GM diet, the liver potentially being a primary target. In a previous study, we demonstrated that some modifications occur in hepatocyte nuclei of mice fed on GM soybean. In order to elucidate whether such modifications can be reversed, in the present study, 3 months old mice fed on GM soybean since their weaning were submitted to a diet containing wild type soybean only, for one month. In parallel, to investigate the influence of GM soybean on adult individuals, mice fed on wild type soybean were changed to a GM diet, for the same time. Using immunoelectron microscopy, we demonstrated that a one-month diet reversion can influence some nuclear features in adult mice, restoring typical characteristics of controls in GM-fed animals, and inducing in control mice modifications similar to those observed in animals fed on GM soybean from weaning. This suggests that the modifications related to GM soybean are potentially reversible, but also that some modifications are inducible in adult organisms in a short time.

Gene Flow in Genetically Engineered Perennial Grasses: Lessons for Modification of Dedicated Bioenergy Crops

Science.gov (United States)

Genetic modification of dedicated bioenergy crops, such as switchgrass, will play a major role in crop improvement for a wide range of beneficial traits specific to biofuels. One obstacle that arises regarding transgenic improvement of perennials used for biofuels is the propensity of these plants t...

Recent patents on genetic modification of plants and microbes for biomass conversion to biofuels.

Science.gov (United States)

Lubieniechi, Simona; Peranantham, Thinesh; Levin, David B

2013-04-01

Development of sustainable energy systems based on renewable biomass feedstocks is now a global effort. Lignocellulosic biomass contains polymers of cellulose, hemicellulose, and lignin, bound together in a complex structure. Liquid biofuels, such as ethanol, can be made from biomass via fermentation of sugars derived from the cellulose and hemicellulose within lignocellulosic materials, but pre-treatment of the biomass to release sugars for microbial conversion is a significant barrier to commercial success of lignocellulosic biofuel production. Strategies to reduce the energy and cost inputs required for biomass pre-treatment include genetic modification of plant materials to reduce lignin content. Significant efforts are also underway to create recombinant microorganisms capable of converting sugars derived from lignocellulosic biomass to a variety of biofuels. An alternative strategy to reduce the costs of cellulosic biofuel production is the use of cellulolytic microorganisms capable of direct microbial conversion of ligno-cellulosic biomass to fuels. This paper reviews recent patents on genetic modification of plants and microbes for biomass conversion to biofuels.

Effect of genetic modification of potato starch on decomposition of leaves and tubers and on fungal decomposer communities

NARCIS (Netherlands)

Hannula, S.E.; De Boer, W.; Baldrian, P.; Van Veen, J.A.

2013-01-01

As part of a risk evaluation of growing genetically modified crops, we investigated the effects of a genetic modification of starch quality (increased level of amylopectin) in potato tubers (Solanum Tuberosum L.) on the decomposition of tissues (tubers and leaves) as well as on the associated fungal

Liberal or Conservative? Genetic Rhetoric, Disability, and Human Species Modification

Directory of Open Access Journals (Sweden)

Christopher F. Goodey

2016-11-01

Full Text Available A certain political rhetoric is implicit and sometimes explicit in the advocacy of human genetic modification (indicating here both the enhancement and the prevention of disability. The main claim is that it belongs to a liberal tradition. From a perspective supplied by the history and philosophy of science rather than by ethics, the content of that claim is examined to see if such a self-description is justified. The techniques are analyzed by which apparently liberal arguments get to be presented as “reasonable” in a juridical sense that draws on theories of law and rhetoric.

Improving efficacy of cancer immunotherapy by genetic modification of natural killer cells.

Science.gov (United States)

Burga, Rachel A; Nguyen, Tuongvan; Zulovich, Jane; Madonna, Sarah; Ylisastigui, Loyda; Fernandes, Rohan; Yvon, Eric

2016-11-01

Natural killer (NK) cells are members of the innate immune system that recognize target cells via activating and inhibitory signals received through cell receptors. Derived from the lymphoid lineage, NK cells are able to produce cytokines and exert a cytotoxic effect on viral infected and malignant cells. It is their unique ability to lyse target cells rapidly and without prior education that renders NK cells a promising effector cell for adoptive cell therapy. However, both viruses and tumors employ evasion strategies to avoid attack by NK cells, which represent biological challenges that need to be harnessed to fully exploit the cytolytic potential of NK cells. Using genetic modification, the function of NK cells can be enhanced to improve their homing, cytolytic activity, in vivo persistence and safety. Examples include gene modification to express chemokine, high-affinity Fc receptor and chimeric antigen receptors, suicide genes and the forced expression of cytokines such as interleukin (IL)-2 and IL-15. Preclinical studies have clearly demonstrated that such approaches are effective in improving NK-cell function, homing and safety. In this review, we summarize the recent advances in the genetic manipulations of NK cells and their application for cellular immunotherapeutic strategies. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Effects of inbreeding and genetic modification on Aedes aegypti larval competition and adult energy reserves

NARCIS (Netherlands)

Koenraadt, C.J.M.; Kormaksson, M.; Harrington, L.C.

2010-01-01

Background - Genetic modification of mosquitoes offers a promising strategy for the prevention and control of mosquito-borne diseases. For such a strategy to be effective, it is critically important that engineered strains are competitive enough to serve their intended function in population

Modification of the genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The authors study the effect of direct current of varying strength and polarity on the genetic damage due to gamma irradiation of Vicia faba seedlings. The modificational effect of direct current observed earlier is confirmed here. The extent and nature of this effect depends on the strength and polarity of the current as well as interval between irradiation and exposure to the electric field. Conditions having no effect on the irradiated seedlings, those protecting the cells from damage and enhancing the irradiation effect, are identified

Four questions on European consumers' attitudes to the use of genetic modification in food production

DEFF Research Database (Denmark)

Grunert, Klaus G.; Bredahl, Lone; Scholderer, Joachim

2003-01-01

Four questions on European consumers' attitudes to the use of genetic modification (GM) in food production are posed and answered: (1) how negative are consumer attitudes to GM applications in food production? (2) How do these attitudes affect perception of and preference for products involving GM...

Genetic modification of stem cells for improved therapy of the infarcted myocardium.

Science.gov (United States)

Haider, Husnain Kh; Mustafa, Anique; Feng, Yuliang; Ashraf, Muhammad

2011-10-03

The conventional treatment modalities for ischemic heart disease only provide symptomatic relief to the patient without repairing and regenerating the damaged myocardium. Stem cell transplantation has emerged as a promising alternative therapeutic approach for cardiovascular diseases. Stem cells possess the potential of differentiation to adopt morphofunctional cardiac and vasculogenic phenotypes to repopulate the scar tissue and restore regional blood flow in the ischemic myocardium. These beneficial therapeutic effects make stem cell transplantation the method of choice for the treatment of ischemic heart disease. The efficacy of stem cell transplantation may be augmented by genetic manipulation of the cells prior to transplantation. Not only will insertion of therapeutic transgene(s) into the stem cells support the survival and differentiation of cells in the unfavorable microenvironment of the ischemic myocardium, but also the genetically manipulated stem cells will serve as a source of the transgene expression product in the heart for therapeutic benefits. We provide an overview of the extensively studied stem cell types for cardiac regeneration, the various methods in which these cells have been genetically manipulated and rationale of genetic modification of stem cells for use in regenerative cardiovascular therapeutics.

Genetic Modification in Human Pluripotent Stem Cells by Homologous Recombination and CRISPR/Cas9 System.

Science.gov (United States)

Xue, Haipeng; Wu, Jianbo; Li, Shenglan; Rao, Mahendra S; Liu, Ying

2016-01-01

Genetic modification is an indispensable tool to study gene function in normal development and disease. The recent breakthrough of creating human induced pluripotent stem cells (iPSCs) by defined factors (Takahashi et al., Cell 131:861-872, 2007) provides a renewable source of patient autologous cells that not only retain identical genetic information but also give rise to many cell types of the body including neurons and glia. Meanwhile, the rapid advancement of genome modification tools such as gene targeting by homologous recombination (Capecchi, Nat Rev Genet 6:507-512, 2005) and genome editing tools such as CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas (CRISPR-associated) system, TALENs (Transcription activator-like effector nucleases), and ZFNs (Zinc finger nucleases) (Wang et al., Cell 153:910-918, 2013; Mali et al., Science 339:823-826, 2013; Hwang et al., Nat Biotechnol 31:227-229, 2013; Friedland et al., Nat Methods 10(8):741-743, 2013; DiCarlo et al., Nucleic Acids Res 41:4336-4343, 2013; Cong et al., Science 339:819-823, 2013) has greatly accelerated the development of human genome manipulation at the molecular level. This chapter describes the protocols for making neural lineage reporter lines using homologous recombination and the CRISPR/Cas system-mediated genome editing, including construction of targeting vectors, guide RNAs, transfection into hPSCs, and selection and verification of successfully targeted clones. This method can be applied to various needs of hPSC genetic engineering at high efficiency and high reliability.

Supernatural T cells: genetic modification of T cells for cancer therapy.

Science.gov (United States)

Kershaw, Michael H; Teng, Michele W L; Smyth, Mark J; Darcy, Phillip K

2005-12-01

Immunotherapy is receiving much attention as a means of treating cancer, but complete, durable responses remain rare for most malignancies. The natural immune system seems to have limitations and deficiencies that might affect its ability to control malignant disease. An alternative to relying on endogenous components in the immune repertoire is to generate lymphocytes with abilities that are greater than those of natural T cells, through genetic modification to produce 'supernatural' T cells. This Review describes how such T cells can circumvent many of the barriers that are inherent in the tumour microenvironment while optimizing T-cell specificity, activation, homing and antitumour function.

Genetic modification of hematopoietic stem cells as a therapy for HIV/AIDS.

Science.gov (United States)

Younan, Patrick; Kowalski, John; Kiem, Hans-Peter

2013-11-28

The combination of genetic modification and hematopoietic stem cell (HSC) transplantation may provide the necessary means to develop an alternative treatment option to conventional antiretroviral therapy. As HSCs give rise to all hematopoietic cell types susceptible to HIV infection, modification of HSCs is an ideal strategy for the development of infection-resistant immune cell populations. Although promising results have been obtained in multiple animal models, additional evidence is needed to convincingly demonstrate the feasibility of this approach as a treatment of HIV-1 infected patients. Here, we review the potential of HSC transplantation and the recently identified limitations of this approach. Using the Berlin Patient as a model for a functional cure, we contrast the confines of autologous versus allogeneic transplantation. Finally, we suggest that although autologous, gene-modified HSC-transplantation may significantly reduce plasma viremia, reaching the lower detection limits currently obtainable through daily HAART will remain a challenging endeavor that will require innovative combinatorial therapies.

Genetic Modification of Hematopoietic Stem Cells as a Therapy for HIV/AIDS

Directory of Open Access Journals (Sweden)

Patrick Younan

2013-11-01

Full Text Available The combination of genetic modification and hematopoietic stem cell (HSC transplantation may provide the necessary means to develop an alternative treatment option to conventional antiretroviral therapy. As HSCs give rise to all hematopoietic cell types susceptible to HIV infection, modification of HSCs is an ideal strategy for the development of infection-resistant immune cell populations. Although promising results have been obtained in multiple animal models, additional evidence is needed to convincingly demonstrate the feasibility of this approach as a treatment of HIV-1 infected patients. Here, we review the potential of HSC transplantation and the recently identified limitations of this approach. Using the Berlin Patient as a model for a functional cure, we contrast the confines of autologous versus allogeneic transplantation. Finally, we suggest that although autologous, gene-modified HSC-transplantation may significantly reduce plasma viremia, reaching the lower detection limits currently obtainable through daily HAART will remain a challenging endeavor that will require innovative combinatorial therapies.

Scalable human ES culture for therapeutic use: propagation, differentiation, genetic modification and regulatory issues.

Science.gov (United States)

Rao, M

2008-01-01

Embryonic stem cells unlike most adult stem cell populations can replicate indefinitely while preserving genetic, epigenetic, mitochondrial and functional profiles. ESCs are therefore an excellent candidate cell type for providing a bank of cells for allogenic therapy and for introducing targeted genetic modifications for therapeutic intervention. This ability of prolonged self-renewal of stem cells and the unique advantages that this offers for gene therapy, discovery efforts, cell replacement, personalized medicine and other more direct applications requires the resolution of several important manufacturing, gene targeting and regulatory issues. In this review, we assess some of the advance made in developing scalable culture systems, improvement in vector design and gene insertion technology and the changing regulatory landscape.

Advances in genetic modification of pluripotent stem cells.

Science.gov (United States)

Fontes, Andrew; Lakshmipathy, Uma

2013-11-15

Genetically engineered stem cells aid in dissecting basic cell function and are valuable tools for drug discovery, in vivo cell tracking, and gene therapy. Gene transfer into pluripotent stem cells has been a challenge due to their intrinsic feature of growing in clusters and hence not amenable to common gene delivery methods. Several advances have been made in the rapid assembly of DNA elements, optimization of culture conditions, and DNA delivery methods. This has lead to the development of viral and non-viral methods for transient or stable modification of cells, albeit with varying efficiencies. Most methods require selection and clonal expansion that demand prolonged culture and are not suited for cells with limited proliferative potential. Choosing the right platform based on preferred length, strength, and context of transgene expression is a critical step. Random integration of the transgene into the genome can be complicated due to silencing or altered regulation of expression due to genomic effects. An alternative to this are site-specific methods that target transgenes followed by screening to identify the genomic loci that support long-term expression with stem cell proliferation and differentiation. A highly precise and accurate editing of the genome driven by homology can be achieved using traditional methods as well as the newer technologies such as zinc finger nuclease, TAL effector nucleases and CRISPR. In this review, we summarize the different genetic engineering methods that have been successfully used to create modified embryonic and induced pluripotent stem cells. © 2013. Published by Elsevier Inc. All rights reserved.

Genetic modification and its impact on industry structure and performance: post-harvest deterioration of cassava in Thailand

NARCIS (Netherlands)

Vlaar, P.W.L.; Beek, van P.; Visser, R.G.F.

2007-01-01

Genetic modification has led to fierce debates around the world. Nevertheless, scientific evidence for its potential effects on the structure and performance of industries has hitherto remained rather meagre. In this article, we take some preliminary steps towards closing this gap by exploring the

Bioengineering a non-genotoxic vector for genetic modification of mesenchymal stem cells.

Science.gov (United States)

Chen, Xuguang; Nomani, Alireza; Patel, Niket; Nouri, Faranak S; Hatefi, Arash

2018-01-01

Vectors used for stem cell transfection must be non-genotoxic, in addition to possessing high efficiency, because they could potentially transform normal stem cells into cancer-initiating cells. The objective of this research was to bioengineer an efficient vector that can be used for genetic modification of stem cells without any negative somatic or genetic impact. Two types of multifunctional vectors, namely targeted and non-targeted were genetically engineered and purified from E. coli. The targeted vectors were designed to enter stem cells via overexpressed receptors. The non-targeted vectors were equipped with MPG and Pep1 cell penetrating peptides. A series of commercial synthetic non-viral vectors and an adenoviral vector were used as controls. All vectors were evaluated for their efficiency and impact on metabolic activity, cell membrane integrity, chromosomal aberrations (micronuclei formation), gene dysregulation, and differentiation ability of stem cells. The results of this study showed that the bioengineered vector utilizing VEGFR-1 receptors for cellular entry could transfect mesenchymal stem cells with high efficiency without inducing genotoxicity, negative impact on gene function, or ability to differentiate. Overall, the vectors that utilized receptors as ports for cellular entry (viral and non-viral) showed considerably better somato- and genosafety profiles in comparison to those that entered through electrostatic interaction with cellular membrane. The genetically engineered vector in this study demonstrated that it can be safely and efficiently used to genetically modify stem cells with potential applications in tissue engineering and cancer therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structural modification of polysaccharides: A biochemical-genetic approach

Science.gov (United States)

Kern, Roger G.; Petersen, Gene R.

1991-01-01

Polysaccharides have a wide range of industrial and biomedical applications. An industry trend is underway towards the increased use of bacteria to produce polysaccharides. Long term goals of this work are the adaptation and enhancement of saccharide properties for electronic and optic applications. In this report we illustrate the application of enzyme-bearing bacteriophage on strains of the enteric bacterium Klebsiella pneumoniae, which produces a polysaccharide with the relatively rare rheological property of drag-reduction. This has resulted in the production of new polysaccharides with enhanced rheological properties. Our laboratory is developing techniques for processing and structurally modifying bacterial polysaccharides and oligosaccharides which comprise their basic polymeric repeat units. Our research has focused on bacteriophage which produce specific polysaccharide degrading enzymes. This has lead to the development of enzymes generated by bacteriophage as tools for polysaccharide modification and purification. These enzymes were used to efficiently convert the native material to uniform-sized high molecular weight polymers, or alternatively into high-purity oligosaccharides. Enzyme-bearing bacteriophage also serve as genetic selection tools for bacteria that produce new families of polysaccharides with modified structures.

Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola

Directory of Open Access Journals (Sweden)

Rabia Arif

2017-01-01

Full Text Available Posttranslational modifications (PTMs occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment on proteins or various amino acids pickings and their ultimate impact on consensus sequences present in mating type proteins using bioinformatics tools. Furthermore, we have also measured and walked through genomic DNA of various Sordaria strains to determine genetic diversity by genotyping the short sequence repeats (SSRs of wild strains of S. fimicola collected from contrasting environments of two opposing slopes (harsh and xeric south facing slope and mild north facing slope of Evolution Canyon (EC, Israel. Based on the whole genome sequence of S. macrospora, we targeted 20 genomic regions in S. fimicola which contain short sequence repeats (SSRs. Our data revealed genetic variations in strains from south facing slope and these findings assist in the hypothesis that genetic variations caused by stressful environments lead to evolution.

Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola.

Science.gov (United States)

Arif, Rabia; Akram, Faiza; Jamil, Tazeen; Mukhtar, Hamid; Lee, Siu Fai; Saleem, Muhammad

2017-01-01

Posttranslational modifications (PTMs) occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment on proteins or various amino acids pickings and their ultimate impact on consensus sequences present in mating type proteins using bioinformatics tools. Furthermore, we have also measured and walked through genomic DNA of various Sordaria strains to determine genetic diversity by genotyping the short sequence repeats (SSRs) of wild strains of S. fimicola collected from contrasting environments of two opposing slopes (harsh and xeric south facing slope and mild north facing slope) of Evolution Canyon (EC), Israel. Based on the whole genome sequence of S. macrospora , we targeted 20 genomic regions in S. fimicola which contain short sequence repeats (SSRs). Our data revealed genetic variations in strains from south facing slope and these findings assist in the hypothesis that genetic variations caused by stressful environments lead to evolution.

Genetic modification of chondrocytes with insulin-like growth factor-1 enhances cartilage healing in an equine model.

Science.gov (United States)

Goodrich, L R; Hidaka, C; Robbins, P D; Evans, C H; Nixon, A J

2007-05-01

Gene therapy with insulin-like growth factor-1 (IGF-1) increases matrix production and enhances chondrocyte proliferation and survival in vitro. The purpose of this study was to determine whether arthroscopically-grafted chondrocytes genetically modified by an adenovirus vector encoding equine IGF-1 (AdIGF-1) would have a beneficial effect on cartilage healing in an equine femoropatellar joint model. A total of 16 horses underwent arthroscopic repair of a single 15 mm cartilage defect in each femoropatellar joint. One joint received 2 x 10(7) AdIGF-1 modified chondrocytes and the contralateral joint received 2 x 10(7) naive (unmodified) chondrocytes. Repairs were analysed at four weeks, nine weeks and eight months after surgery. Morphological and histological appearance, IGF-1 and collagen type II gene expression (polymerase chain reaction, in situ hybridisation and immunohistochemistry), collagen type II content (cyanogen bromide and sodium dodecyl sulphate-polyacrylamide gel electrophoresis), proteoglycan content (dimethylmethylene blue assay), and gene expression for collagen type I, matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, aggrecanase-1, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and TIMP-3 were evaluated. Genetic modification of chondrocytes significantly increased IGF-1 mRNA and ligand production in repair tissue for up to nine weeks following transplantation. The gross and histological appearance of IGF-1 modified repair tissue was improved over control defects. Gross filling of defects was significantly improved at four weeks, and a more hyaline-like tissue covered the lesions at eight months. Histological outcome at four and nine weeks post-transplantation revealed greater tissue filling of defects transplanted with genetically modified chondrocytes, whereas repair tissue in control defects was thin and irregular and more fibrous. Collagen type II expression in IGF-1 gene-transduced defects was increased 100-fold at four weeks and

Conversing about Citrus Greening: Extension's Role in Educating about Genetic Modification Science as a Solution

Science.gov (United States)

Ruth, Taylor K.; Lamm, Alexa J.; Rumble, Joy N.; Ellis, Jason D.

2017-01-01

Extension agents across the nation will need to facilitate difficult conversations with the public if genetic modification (GM) science is used to combat citrus greening disease. This study used the innovation characteristics described by Rogers to explore if using GM science as a solution to citrus greening had diffused amongst US residents. An…

Genetic Modification of Lignin in Hybrid Poplar (Populus alba × Populus tremula) Does Not Substantially Alter Plant Defense or Arthropod Communities.

Science.gov (United States)

Buhl, Christine; Meilan, Richard; Lindroth, Richard L

2017-05-01

Lignin impedes access to cellulose during biofuel production and pulping but trees can be genetically modified to improve processing efficiency. Modification of lignin may have nontarget effects on mechanical and chemical resistance and subsequent arthropod community responses with respect to pest susceptibility and arthropod biodiversity. We quantified foliar mechanical and chemical resistance traits in lignin-modified and wild-type (WT) poplar (Populus alba × Populus tremula) grown in a plantation and censused arthropods present on these trees to determine total abundance, as well as species richness, diversity and community composition. Our results indicate that mechanical resistance was not affected by lignin modification and only one genetic construct resulted in a (modest) change in chemical resistance. Arthropod abundance and community composition were consistent across modified and WT trees, but transgenics produced using one construct exhibited higher species richness and diversity relative to the WT. Our findings indicate that modification of lignin in poplar does not negatively affect herbivore resistance traits or arthropod community response, and may even result in a source of increased genetic diversity in trees and arthropod communities. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Genetic Evidence for Modifying Oceanic Boundaries Relative to Fiji.

Science.gov (United States)

Shipley, Gerhard P; Taylor, Diana A; N'Yeurt, Antoine D R; Tyagi, Anand; Tiwari, Geetanjali; Redd, Alan J

2016-07-01

We present the most comprehensive genetic characterization to date of five Fijian island populations: Viti Levu, Vanua Levu, Kadavu, the Lau Islands, and Rotuma, including nonrecombinant Y (NRY) chromosome and mitochondrial DNA (mtDNA) haplotypes and haplogroups. As a whole, Fijians are genetically intermediate between Melanesians and Polynesians, but the individual Fijian island populations exhibit significant genetic structure reflecting different settlement experiences in which the Rotumans and the Lau Islanders were more influenced by Polynesians, and the other Fijian island populations were more influenced by Melanesians. In particular, Rotuman and Lau Islander NRY chromosomal and mtDNA haplogroup frequencies and Rotuman mtDNA hypervariable segment 1 region haplotypes more closely resemble those of Polynesians, while genetic markers of the other populations more closely resemble those of the Near Oceanic Melanesians. Our findings provide genetic evidence supportive of modifying regional boundaries relative to Fiji, as has been suggested by others based on a variety of nongenetic evidence. Specifically, for the traditional Melanesia/Polynesia/Micronesia scheme, our findings support moving the Melanesia-Polynesia boundary to include Rotuma and the Lau Islands in Polynesia. For the newer Near/Remote Oceania scheme, our findings support keeping Rotuma and the Lau Islands in Remote Oceania and locating the other Fijian island populations in an intermediate or "Central Oceania" region to better reflect the great diversity of Oceania.

Detection of thermogenesis in rodents in response to anti-obesity drugs and genetic modification

Directory of Open Access Journals (Sweden)

Jonathan R S Arch

2013-04-01

Full Text Available Many compounds and genetic manipulations are claimed to confer resistance to obesity in rodents by raising energy expenditure. Examples taken from recent and older literature, demonstrate that such claims are often based on measurements of energy expenditure after body composition has changed and depend on comparisons of energy expenditure divided by body weight. This is misleading because white adipose tissue has less influence than lean tissue on energy expenditure. Application of this approach to human data would suggest that human obesity is usually due to a low metabolic rate, which is not an accepted view. Increased energy expenditure per animal is a surer way of demonstrating thermogenesis, but even then it is important to know whether this is due to altered body composition (repartitioning, or increased locomotor activity rather than thermogenesis per se. Regression analysis offers other approaches. The thermogenic response to some compounds has a rapid onset and so cannot be due to altered body composition. These compounds usually mimic or activate the sympathetic nervous system. Thermogenesis occurs in, but may not be confined to, brown adipose tissue. It should not be assumed that weight loss in response to these treatments is due to thermogenesis unless there is a sustained increase in 24-h energy expenditure. Thyroid hormones and fibroblast growth factor 21 also raise energy expenditure before they affect body composition. Some treatments and genetic modifications alter the diurnal rhythm of energy expenditure. It is important to establish whether this is due to altered locomotor activity or efficiency of locomotion. There are no good examples of compounds that do not affect short-term energy expenditure but have a delayed effect. How and under what conditions a genetic modification or compound increases energy expenditure influences the decision on whether to seek drugs for the target or take a candidate drug into clinical studies.

Tolerance to MHC class II disparate allografts through genetic modification of bone marrow

Science.gov (United States)

Jindra, Peter T.; Tripathi, Sudipta; Tian, Chaorui; Iacomini, John; Bagley, Jessamyn

2012-01-01

Induction of molecular chimerism through genetic modification of bone marrow is a powerful tool for the induction of tolerance. Here we demonstrate for the first time that expression of an allogeneic MHC class II gene in autologous bone marrow cells, resulting in a state of molecular chimerism, induces tolerance to MHC class II mismatched skin grafts, a stringent test of transplant tolerance. Reconstitution of recipients with syngeneic bone marrow transduced with retrovirus encoding H-2I-Ab (I-Ab) resulted the long-term expression of the retroviral gene product on the surface of MHC class II-expressing bone marrow derived cell types. Mechanistically, tolerance was maintained by the presence of regulatory T cells, which prevented proliferation and cytokine production by alloreactive host T cells. Thus, the introduction of MHC class II genes into bone marrow derived cells through genetic engineering results in tolerance. These results have the potential to extend the clinical applicability of molecular chimerism for tolerance induction. PMID:22833118

Genetic modification of cerebral arterial wall: implications for prevention and treatment of cerebral vasospasm.

Science.gov (United States)

Vijay, Anantha; Santhanam, R; Katusic, Zvonimir S

2006-10-01

Genetic modification of cerebral vessels represents a promising and novel approach for prevention and/or treatment of various cerebral vascular disorders, including cerebral vasospasm. In this review, we focus on the current understanding of the use of gene transfer to the cerebral arteries for prevention and/or treatment of cerebral vasospasm following subarachnoid hemorrhage (SAH). We also discuss the recent developments in vascular therapeutics, involving the autologous use of progenitor cells for repair of damaged vessels, as well as a cell-based gene delivery approach for the prevention and treatment of cerebral vasospasm.

An injectable spheroid system with genetic modification for cell transplantation therapy.

Science.gov (United States)

Uchida, Satoshi; Itaka, Keiji; Nomoto, Takahiro; Endo, Taisuke; Matsumoto, Yu; Ishii, Takehiko; Kataoka, Kazunori

2014-03-01

The new methodology to increase a therapeutic potential of cell transplantation was developed here by the use of three-dimensional spheroids of transplanting cells subsequent to the genetic modification with non-viral DNA vectors, polyplex nanomicelles. Particularly, spheroids in regulated size of 100-μm of primary hepatocytes transfected with luciferase gene were formed on the micropatterned culture plates coated with thermosensitive polymer, and were recovered in the form of injectable liquid suspension simply by cooling the plates. After subcutaneously transplanting these hepatocyte spheroids, efficient transgene expression was observed in host tissue for more than a month, whereas transplantation of a single-cell suspension from a monolayer culture resulted in an only transient expression. The spheroid system contributed to the preservation of innate functions of transplanted hepatocytes in the host tissue, such as albumin expression, thereby possessing high potential for expressing transgene. Intravital observation of transplanted cells showed that those from spheroid cultures had a tendency to localize in the vicinity of blood vessels, making a favorable microenvironment for preserving cell functionality. Furthermore, spheroids transfected with erythropoietin-expressing DNA showed a significantly higher hematopoietic effect than that of cell suspensions from monolayer cultures, demonstrating high potential of this genetically-modified spheroid transplantation system for therapeutic applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

On the genetic modification of psychology, personality, and behavior.

Science.gov (United States)

Neitzke, Alex B

2012-12-01

I argue that the use of heritable modifications for psychology, personality, and behavior should be limited to the reversal or prevention of relatively unambiguous instances of pathology or likely harm (e.g. sociopathy). Most of the likely modifications of psychological personality would not be of this nature, however, and parents therefore should not have the freedom to make such modifications to future children. I argue by examining the viewpoints of both the individual and society. For individuals, modifications would interfere with their capacity for self-determination in a way that undermines the very concept of self-determination. I argue that modification of psychology and personality is unlike present parenting in morally significant ways. For society, modification offers a medium for power to manipulate the makeup of persons and populations, possibly causing biological harm to the species and altering our conceptions of social responsibility.

HMCan-diff: a method to detect changes in histone modifications in cells with different genetic characteristics

KAUST Repository

Ashoor, Haitham

2016-12-19

Comparing histone modification profiles between cancer and normal states, or across different tumor samples, can provide insights into understanding cancer initiation, progression and response to therapy. ChIP-seq histone modification data of cancer samples are distorted by copy number variation innate to any cancer cell. We present HMCan-diff, the first method designed to analyze ChIP-seq data to detect changes in histone modifications between two cancer samples of different genetic backgrounds, or between a cancer sample and a normal control. HMCan-diff explicitly corrects for copy number bias, and for other biases in the ChIP-seq data, which significantly improves prediction accuracy compared to methods that do not consider such corrections. On in silico simulated ChIP-seq data generated using genomes with differences in copy number profiles, HMCan-diff shows a much better performance compared to other methods that have no correction for copy number bias. Additionally, we benchmarked HMCan-diff on four experimental datasets, characterizing two histone marks in two different scenarios. We correlated changes in histone modifications between a cancer and a normal control sample with changes in gene expression. On all experimental datasets, HMCan-diff demonstrated better performance compared to the other methods.

Pnp gene modification for improved xylose utilization in Zymomonas

Science.gov (United States)

Caimi, Perry G G; Qi, Min; Tao, Luan; Viitanen, Paul V; Yang, Jianjun

2014-12-16

The endogenous pnp gene encoding polynucleotide phosphorylase in the Zymomonas genome was identified as a target for modification to provide improved xylose utilizing cells for ethanol production. The cells are in addition genetically modified to have increased expression of ribose-5-phosphate isomerase (RPI) activity, as compared to cells without this genetic modification, and are not limited in xylose isomerase activity in the absence of the pnp modification.

Safe genetic modification of cardiac stem cells using a site-specific integration technique.

Science.gov (United States)

Lan, Feng; Liu, Junwei; Narsinh, Kazim H; Hu, Shijun; Han, Leng; Lee, Andrew S; Karow, Marisa; Nguyen, Patricia K; Nag, Divya; Calos, Michele P; Robbins, Robert C; Wu, Joseph C

2012-09-11

Human cardiac progenitor cells (hCPCs) are a promising cell source for regenerative repair after myocardial infarction. Exploitation of their full therapeutic potential may require stable genetic modification of the cells ex vivo. Safe genetic engineering of stem cells, using facile methods for site-specific integration of transgenes into known genomic contexts, would significantly enhance the overall safety and efficacy of cellular therapy in a variety of clinical contexts. We used the phiC31 site-specific recombinase to achieve targeted integration of a triple fusion reporter gene into a known chromosomal context in hCPCs and human endothelial cells. Stable expression of the reporter gene from its unique chromosomal integration site resulted in no discernible genomic instability or adverse changes in cell phenotype. Namely, phiC31-modified hCPCs were unchanged in their differentiation propensity, cellular proliferative rate, and global gene expression profile when compared with unaltered control hCPCs. Expression of the triple fusion reporter gene enabled multimodal assessment of cell fate in vitro and in vivo using fluorescence microscopy, bioluminescence imaging, and positron emission tomography. Intramyocardial transplantation of genetically modified hCPCs resulted in significant improvement in myocardial function 2 weeks after cell delivery, as assessed by echocardiography (P=0.002) and MRI (P=0.001). We also demonstrated the feasibility and therapeutic efficacy of genetically modifying differentiated human endothelial cells, which enhanced hind limb perfusion (Pmodification system is a safe, efficient tool to enable site-specific integration of reporter transgenes in progenitor and differentiated cell types.

Genetic Engineering: The Modification of Man

Science.gov (United States)

Sinsheimer, Robert L.

1970-01-01

Describes somatic and genetic manipulations of individual genotypes, using diabetes control as an example of the first mode that is potentially realizable be derepression or viral transduction of genes. Advocates the use of genetic engineering of the second mode to remove man from his biological limitations, but offers maxims to ensure the…

The Choice of Pre-Birth Genetic Modification : Through Kant´s Ethics in the 21st Century

OpenAIRE

Dumisic, Sanjin

2016-01-01

This essay discusses, departing from Kant’s deontological ethics, and deals with the ques- tion of which types of pre-birth genetic modification are acceptable from the perspective of Kant’s ethics theory? The conclusion is that Kant’s ethics can be in line with certain thera- peutic interventions. Yet the same ethics disapproves with any sort of pre-birth modifica- tion based on personal design, preferences and commodification of the process.

Recent advances in genetic modification of adenovirus vectors for cancer treatment.

Science.gov (United States)

Yamamoto, Yuki; Nagasato, Masaki; Yoshida, Teruhiko; Aoki, Kazunori

2017-05-01

Adenoviruses are widely used to deliver genes to a variety of cell types and have been used in a number of clinical trials for gene therapy and oncolytic virotherapy. However, several concerns must be addressed for the clinical use of adenovirus vectors. Selective delivery of a therapeutic gene by adenovirus vectors to target cancer is precluded by the widespread distribution of the primary cellular receptors. The systemic administration of adenoviruses results in hepatic tropism independent of the primary receptors. Adenoviruses induce strong innate and acquired immunity in vivo. Furthermore, several modifications to these vectors are necessary to enhance their oncolytic activity and ensure patient safety. As such, the adenovirus genome has been engineered to overcome these problems. The first part of the present review outlines recent progress in the genetic modification of adenovirus vectors for cancer treatment. In addition, several groups have recently developed cancer-targeting adenovirus vectors by using libraries that display random peptides on a fiber knob. Pancreatic cancer-targeting sequences have been isolated, and these oncolytic vectors have been shown by our group to be associated with a higher gene transduction efficiency and more potent oncolytic activity in cell lines, murine models, and surgical specimens of pancreatic cancer. In the second part of this review, we explain that combining cancer-targeting strategies can be a promising approach to increase the clinical usefulness of oncolytic adenovirus vectors. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Development of a Recombination System for the Generation of Occlusion Positive Genetically Modified Anticarsia Gemmatalis Multiple Nucleopolyhedrovirus

Directory of Open Access Journals (Sweden)

Santiago Haase

2015-03-01

Full Text Available Anticarsia gemmatalis is an important pest in legume crops in South America and it has been successfully controlled using Anticarsia gemmatalis Multiple Nucleopolyhedrovirus (AgMNPV in subtropical climate zones. Nevertheless, in temperate climates its speed of kill is too slow. Taking this into account, genetic modification of AgMNPV could lead to improvements of its biopesticidal properties. Here we report the generation of a two-component system that allows the production of recombinant AgMNPV. This system is based on a parental AgMNPV in which the polyhedrin gene (polh was replaced by a bacterial β-galactosidase (lacZ gene flanked by two target sites for the homing endonuclease I-PpoI. Co-transfection of insect cells with linearized (I-PpoI-digested parental genome and a transfer vector allowed the restitution of polh and the expression of a heterologous gene upon homologous recombination, with a low background of non-recombinant AgMNPV. The system was validated by constructing a recombinant occlusion-positive (polh+ AgMNPV expressing the green fluorescent protein gene (gfp. This recombinant virus infected larvae normally per os and led to the expression of GFP in cell culture as well as in A. gemmatalis larvae. These results demonstrate that the system is an efficient method for the generation of recombinant AgMNPV expressing heterologous genes, which can be used for manifold purposes, including biotechnological and pharmaceutical applications and the production of orally infectious recombinants with improved biopesticidal properties.

The impact of genetic modification of human foods in the 21st century: a review.

Science.gov (United States)

Uzogara, S G

2000-05-01

Genetic engineering of food is the science which involves deliberate modification of the genetic material of plants or animals. It is an old agricultural practice carried on by farmers since early historical times, but recently it has been improved by technology. Many foods consumed today are either genetically modified (GM) whole foods, or contain ingredients derived from gene modification technology. Billions of dollars in U.S. food exports are realized from sales of GM seeds and crops. Despite the potential benefits of genetic engineering of foods, the technology is surrounded by controversy. Critics of GM technology include consumer and health groups, grain importers from European Union (EU) countries, organic farmers, environmentalists, concerned scientists, ethicists, religious rights groups, food advocacy groups, some politicians and trade protectionists. Some of the specific fears expressed by opponents of GM technology include alteration in nutritional quality of foods, potential toxicity, possible antibiotic resistance from GM crops, potential allergenicity and carcinogenicity from consuming GM foods. In addition, some more general concerns include environmental pollution, unintentional gene transfer to wild plants, possible creation of new viruses and toxins, limited access to seeds due to patenting of GM food plants, threat to crop genetic diversity, religious, cultural and ethical concerns, as well as fear of the unknown. Supporters of GM technology include private industries, research scientists, some consumers, U.S. farmers and regulatory agencies. Benefits presented by proponents of GM technology include improvement in fruit and vegetable shelf-life and organoleptic quality, improved nutritional quality and health benefits in foods, improved protein and carbohydrate content of foods, improved fat quality, improved quality and quantity of meat, milk and livestock. Other potential benefits are: the use of GM livestock to grow organs for transplant

Generation and genetic modification of induced pluripotent stem cells.

Science.gov (United States)

Schambach, Axel; Cantz, Tobias; Baum, Christopher; Cathomen, Toni

2010-07-01

The generation of induced pluripotent stem cells (iPSCs) enabled by exogenous expression of the canonical Oct4, Sox2, Klf4 and c-Myc reprogramming factors has opened new ways to create patient- or disease-specific pluripotent cells. iPSCs represent an almost inexhaustible source of cells for targeted differentiation into somatic effector cells and hence are likely to be invaluable for therapeutic applications and disease-related research. After an introduction on the biology of reprogramming we cover emerging technological advances, including new reprogramming approaches, small-molecule compounds and tailored genetic modification, and give an outlook towards potential clinical applications of iPSCs. Although this field is progressing rapidly, reprogramming is still an inefficient process. The reader will learn about innovative tools to generate patient-specific iPSCs and how to modify these established lines in a safe way. Ideally, the disease-causing mutation is edited directly in the genome using novel technologies based on artificial nucleases, such as zinc-finger nucleases. Human iPSCs create fascinating options with regard to disease modeling, drug testing, developmental studies and therapeutic applications. However, important hurdles have to be taken and more efficient protocols to be established to achieve the ambitious goal of bringing iPSCs into clinical use.

Serum-free Erythroid Differentiation for Efficient Genetic Modification and High-Level Adult Hemoglobin Production.

Science.gov (United States)

Uchida, Naoya; Demirci, Selami; Haro-Mora, Juan J; Fujita, Atsushi; Raines, Lydia N; Hsieh, Matthew M; Tisdale, John F

2018-06-15

In vitro erythroid differentiation from primary human cells is valuable to develop genetic strategies for hemoglobin disorders. However, current erythroid differentiation methods are encumbered by modest transduction rates and high baseline fetal hemoglobin production. In this study, we sought to improve both genetic modification and hemoglobin production among human erythroid cells in vitro . To model therapeutic strategies, we transduced human CD34 + cells and peripheral blood mononuclear cells (PBMCs) with lentiviral vectors and compared erythropoietin-based erythroid differentiation using fetal-bovine-serum-containing media and serum-free media. We observed more efficient transduction (85%-93%) in serum-free media than serum-containing media (20%-69%), whereas the addition of knockout serum replacement (KSR) was required for serum-free media to promote efficient erythroid differentiation (96%). High-level adult hemoglobin production detectable by electrophoresis was achieved using serum-free media similar to serum-containing media. Importantly, low fetal hemoglobin production was observed in the optimized serum-free media. Using KSR-containing, serum-free erythroid differentiation media, therapeutic adult hemoglobin production was detected at protein levels with β-globin lentiviral transduction in both CD34 + cells and PBMCs from sickle cell disease subjects. Our in vitro erythroid differentiation system provides a practical evaluation platform for adult hemoglobin production among human erythroid cells following genetic manipulation.

Advancement of Phenotype Transformation of Cancer-associated Fibroblasts: 
from Genetic Alterations to Epigenetic Modification

Directory of Open Access Journals (Sweden)

Dali CHEN

2015-02-01

Full Text Available In the field of human cancer research, even though the vast majority attentions were paid to tumor cells as “the seeds”, the roles of tumor microenvironments as “the soil” are gradually explored in recent years. As a dominant compartment of tumor microenvironments, cancer-associated fibroblasts (CAFs were discovered to correlated with tumorigenesis, tumor progression and prognosis. And the exploration of the mechanisms of CAF phenotype transformation would conducive to the further understand of the CAFs function in human cancers. As we known that CAFs have four main origins, including epithelial cells, endothelial cells, mesenchymal stem cells (MSCs and local mesenchymal cells. However, researchers found that all these origins finally conduct similiar phenotypes from intrinsic to extrinsic ones. Thus, what and how a mechanism can conduct the phenotype transformation of CAFs with different origins? Two viewpoints are proposed to try to answer the quetsion, involving genetic alterations and epigenetic modifications. This review will systematically summarize the advancement of mechanisms of CAF phenotype transformations in the aspect of genentic and epigenetic modifications.

Genetic affinity among five different population groups in India reflecting a Y-chromosome gene flow.

Science.gov (United States)

Saha, Anjana; Sharma, Swarkar; Bhat, Audesh; Pandit, Awadesh; Bamezai, Ramesh

2005-01-01

Four binary polymorphisms and four multiallelic short tandem repeat (STR) loci from the nonrecombining region of the human Y-chromosome were typed in different Indian population groups from Uttar Pradeh (UP), Bihar (BI), Punjab (PUNJ), and Bengal (WB) speaking the Indo-Aryan dialects and from South India (SI) with the root in the Dravidian language. We identified four major haplogroups [(P) 1+, (C and F) 2+, (R1a) 3, (K) 26+] and 114 combinations of Y-STR haplotypes. Analyses of the haplogroups indicated no single origin from any lineage but a result of a conglomeration of different lineages from time to time. The phylogenetic analyses indicate a high degree of population admixture and a greater genetic proximity for the studied population groups when compared with other world populations.

Genetic recombination pathways and their application for genome modification of human embryonic stem cells.

Science.gov (United States)

Nieminen, Mikko; Tuuri, Timo; Savilahti, Harri

2010-10-01

Human embryonic stem cells are pluripotent cells derived from early human embryo and retain a potential to differentiate into all adult cell types. They provide vast opportunities in cell replacement therapies and are expected to become significant tools in drug discovery as well as in the studies of cellular and developmental functions of human genes. The progress in applying different types of DNA recombination reactions for genome modification in a variety of eukaryotic cell types has provided means to utilize recombination-based strategies also in human embryonic stem cells. Homologous recombination-based methods, particularly those utilizing extended homologous regions and those employing zinc finger nucleases to boost genomic integration, have shown their usefulness in efficient genome modification. Site-specific recombination systems are potent genome modifiers, and they can be used to integrate DNA into loci that contain an appropriate recombination signal sequence, either naturally occurring or suitably pre-engineered. Non-homologous recombination can be used to generate random integrations in genomes relatively effortlessly, albeit with a moderate efficiency and precision. DNA transposition-based strategies offer substantially more efficient random strategies and provide means to generate single-copy insertions, thus potentiating the generation of genome-wide insertion libraries applicable in genetic screens. 2010 Elsevier Inc. All rights reserved.

Modification of radiation induced genetic damage and impaired DNA synthesis by thiourea treatment in Solanum incanum L

International Nuclear Information System (INIS)

Kumar, Girish

1991-01-01

Modification of induced genetic damage after exposure to LD 50 and LD 90 doses of 60 Co gamma-irradiation on dormant seeds of Solanum incanum L. by pre- and post-treatments of thiourea was investigated. Thiourea pre-treatment reduced cellular lesions, growth injury and the death of seedlings, while post-treatment increased lethality. Incorporation of 3 H-tymidine into DNA fraction gradually increased with 10 -4 to 10 -2 M thiourea treatment when applied before irradiation. Post-treatment of the thiourea, on the other hand, not only showed poor labelling of DNA but also delayed its synthesis. (author)

A strategy for genetic modification of the spike-encoding segment of human reovirus T3D for reovirus targeting.

Science.gov (United States)

van den Wollenberg, D J M; van den Hengel, S K; Dautzenberg, I J C; Cramer, S J; Kranenburg, O; Hoeben, R C

2008-12-01

Human Orthoreovirus Type 3 Dearing is not pathogenic to humans and has been evaluated clinically as an oncolytic agent. Its transduction efficiency and the tumor cell selectivity may be enhanced by incorporating ligands for alternative receptors. However, the genetic modification of reoviruses has been difficult, and genetic targeting of reoviruses has not been reported so far. Here we describe a technique for generating genetically targeted reoviruses. The propagation of wild-type reoviruses on cells expressing a modified sigma 1-encoding segment embedded in a conventional RNA polymerase II transcript leads to substitution of the wild-type genome segment by the modified version. This technique was used for generating reoviruses that are genetically targeted to an artificial receptor expressed on U118MG cells. These cells lack the junction adhesion molecule-1 and therefore resist infection by wild-type reoviruses. The targeted reoviruses were engineered to carry the ligand for this receptor at the C terminus of the sigma 1 spike protein. This demonstrates that the C terminus of the sigma 1 protein is a suitable locale for the insertion of oligopeptide ligands and that targeting of reoviruses is feasible. The genetically targeted viruses can be propagated using the modified U118MG cells as helper cells. This technique may be applicable for the improvement of human reoviruses as oncolytic agents.

Drug Addiction and DNA Modifications.

Science.gov (United States)

Brown, Amber N; Feng, Jian

2017-01-01

Drug addiction is a complex disorder which can be influenced by both genetic and environmental factors. Research has shown that epigenetic modifications can translate environmental signals into changes in gene expression, suggesting that epigenetic changes may underlie the causes and possibly treatment of substance use disorders. This chapter will focus on epigenetic modifications to DNA, which include DNA methylation and several recently defined additional DNA epigenetic changes. We will discuss the functions of DNA modifications and methods for detecting them, followed by a description of the research investigating the function and consequences of drug-induced changes in DNA methylation patterns. Understanding these epigenetic changes may provide us translational tools for the diagnosis and treatment of addiction in the future.

Highly specific detection of genetic modification events using an enzyme-linked probe hybridization chip.

Science.gov (United States)

Zhang, M Z; Zhang, X F; Chen, X M; Chen, X; Wu, S; Xu, L L

2015-08-10

The enzyme-linked probe hybridization chip utilizes a method based on ligase-hybridizing probe chip technology, with the principle of using thio-primers for protection against enzyme digestion, and using lambda DNA exonuclease to cut multiple PCR products obtained from the sample being tested into single-strand chains for hybridization. The 5'-end amino-labeled probe was fixed onto the aldehyde chip, and hybridized with the single-stranded PCR product, followed by addition of a fluorescent-modified probe that was then enzymatically linked with the adjacent, substrate-bound probe in order to achieve highly specific, parallel, and high-throughput detection. Specificity and sensitivity testing demonstrated that enzyme-linked probe hybridization technology could be applied to the specific detection of eight genetic modification events at the same time, with a sensitivity reaching 0.1% and the achievement of accurate, efficient, and stable results.

Ancient Male Recombination Shaped Genetic Diversity of Neo-Y Chromosome in Drosophila albomicans.

Science.gov (United States)

Satomura, Kazuhiro; Tamura, Koichiro

2016-02-01

Researchers studying Y chromosome evolution have drawn attention to neo-Y chromosomes in Drosophila species due to their resembling the initial stage of Y chromosome evolution. In the studies of neo-Y chromosome of Drosophila miranda, the extremely low genetic diversity observed suggested various modes of natural selection acting on the nonrecombining genome. However, alternative possibility may come from its peculiar origin from a single chromosomal fusion event with male achiasmy, which potentially caused and maintained the low genetic diversity of the neo-Y chromosome. Here, we report a real case where a neo-Y chromosome is in transition from an autosome to a typical Y chromosome. The neo-Y chromosome of Drosophila albomicans harbored a rich genetic diversity comparable to its gametologous neo-X chromosome and an autosome in the same genome. Analyzing sequence variations in 53 genes and measuring recombination rates between pairs of loci by cross experiments, we elucidated the evolutionary scenario of the neo-Y chromosome of D. albomicans having high genetic diversity without assuming selective force, i.e., it originated from a single chromosomal fusion event, experienced meiotic recombination during the initial stage of evolution and diverged from neo-X chromosome by the suppression of recombination tens or a few hundreds of thousand years ago. Consequently, the observed high genetic diversity on the neo-Y chromosome suggested a strong effect of meiotic recombination to introduce genetic variations into the newly arisen sex chromosome. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effects of genetic modifications to flax (Linum usitatissimum) on arbuscular mycorrhiza and plant performance.

Science.gov (United States)

Wróbel-Kwiatkowska, Magdalena; Turnau, Katarzyna; Góralska, Katarzyna; Anielska, Teresa; Szopa, Jan

2012-10-01

Although arbuscular mycorrhizal fungi (AMF) are known for their positive effect on flax growth, the impact of genetic manipulation in this crop on arbuscular mycorrhiza and plant performance was assessed for the first time. Five types of transgenic flax that were generated to improve fiber quality and resistance to pathogens, through increased levels of either phenylpropanoids (W92.40), glycosyltransferase (GT4, GT5), or PR2 beta-1,3-glucanase (B14) or produce polyhydroxybutyrate (M50), were used. Introduced genetic modifications did not change the degree of mycorrhizal colonization as compared to parent cultivars Linola and Nike. Arbuscules were well developed in each tested transgenic type (except M50). In two lines (W92.40 and B14), a higher abundance of arbuscules was observed when compared to control, untransformed flax plants. However, in some cases (W92.40, GT4, GT5, and B14 Md), the mycorrhizal dependency for biomass production of transgenic plants was slightly lower when compared to the original cultivars. No significant influence of mycorrhiza on the photosynthetic activity of transformed lines was found, but in most cases P concentration in mycorrhizal plants remained higher than in nonmycorrhizal ones. The transformed flax lines meet the demands for better quality of fiber and higher resistance to pathogens, without significantly influencing the interaction with AMF.

Genetic modification of the human germ line: The reasons why this project has no future.

Science.gov (United States)

Morange, Michel

2015-01-01

Modification of the human germ line has remained a distant but valuable objective for most biologists since the emergence of genetics (and even before). To study the historical transformations of this project, I have selected three periods - the 1930s, at the pinnacle of eugenics, around 1974 when molecular biology triumphed, and today - and have adopted three criteria to estimate the feasibility of this project: the state of scientific knowledge, the existence of suitable tools, and societal demands. Although the long-awaited techniques to modify the germ line are now available, I will show that most of the expectations behind this project have disappeared, or are considered as being reachable by highly different strategies. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Genetically modified yeast species, and fermentation processes using genetically modified yeast

Energy Technology Data Exchange (ETDEWEB)

Rajgarhia, Vineet [Kingsport, TN; Koivuranta, Kari [Helsinki, FI; Penttila, Merja [Helsinki, FI; Ilmen, Marja [Helsinki, FI; Suominen, Pirkko [Maple Grove, MN; Aristidou, Aristos [Maple Grove, MN; Miller, Christopher Kenneth [Cottage Grove, MN; Olson, Stacey [St. Bonifacius, MN; Ruohonen, Laura [Helsinki, FI

2014-01-07

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetic Modification of Oncolytic Newcastle Disease Virus for Cancer Therapy.

Science.gov (United States)

Cheng, Xing; Wang, Weijia; Xu, Qi; Harper, James; Carroll, Danielle; Galinski, Mark S; Suzich, JoAnn; Jin, Hong

2016-06-01

Clinical development of a mesogenic strain of Newcastle disease virus (NDV) as an oncolytic agent for cancer therapy has been hampered by its select agent status due to its pathogenicity in avian species. Using reverse genetics, we have generated a lead candidate oncolytic NDV based on the mesogenic NDV-73T strain that is no longer classified as a select agent for clinical development. This recombinant NDV has a modification at the fusion protein (F) cleavage site to reduce the efficiency of F protein cleavage and an insertion of a 198-nucleotide sequence into the HN-L intergenic region, resulting in reduced viral gene expression and replication in avian cells but not in mammalian cells. In mammalian cells, except for viral polymerase (L) gene expression, viral gene expression is not negatively impacted or increased by the HN-L intergenic insertion. Furthermore, the virus can be engineered to express a foreign gene while still retaining the ability to grow to high titers in cell culture. The recombinant NDV selectively replicates in and kills tumor cells and is able to drive potent tumor growth inhibition following intratumoral or intravenous administration in a mouse tumor model. The candidate is well positioned for clinical development as an oncolytic virus. Avian paramyxovirus type 1, NDV, has been an attractive oncolytic agent for cancer virotherapy. However, this virus can cause epidemic disease in poultry, and concerns about the potential environmental and economic impact of an NDV outbreak have precluded its clinical development. Here we describe generation and characterization of a highly potent oncolytic NDV variant that is unlikely to cause Newcastle disease in its avian host, representing an essential step toward moving NDV forward as an oncolytic agent. Several attenuation mechanisms have been genetically engineered into the recombinant NDV that reduce chicken pathogenicity to a level that is acceptable worldwide without impacting viral production in

Beware of feedback effects among trust, risk and public opinion: Quantitative estimates of rational versus emotional influences on attitudes toward genetic modification

OpenAIRE

Kelley, Jonathan

2014-01-01

Support for genetic modification in agriculture mainly stems from approval of food and agricultural goals. It is facilitated by trust in the judgment of scientific authorities and undermined by anxiety about the risks involved. But there are symptoms of danger: Any public opinion data that show significant correlations between perceptions of fact (risk, trust etc.) and background characteristics (age, sex, religion, politics) or goals (environmental, medical, economic) typically reflect emoti...

Genetically modified yeast species, and fermentation processes using genetically modified yeast

Energy Technology Data Exchange (ETDEWEB)

Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

2017-09-12

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetically modified yeast species, and fermentation processes using genetically modified yeast

Energy Technology Data Exchange (ETDEWEB)

Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

2016-08-09

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetically modified yeast species and fermentation processes using genetically modified yeast

Energy Technology Data Exchange (ETDEWEB)

Rajgarhia, Vineet [Kingsport, TN; Koivuranta, Kari [Helsinki, FI; Penttila, Merja [Helsinki, FI; Ilmen, Marja [Helsinki, FI; Suominen, Pirkko [Maple Grove, MN; Aristidou, Aristos [Maple Grove, MN; Miller, Christopher Kenneth [Cottage Grove, MN; Olson, Stacey [St. Bonifacius, MN; Ruohonen, Laura [Helsinki, FI

2011-05-17

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications', include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetically modified yeast species and fermentation processes using genetically modified yeast

Science.gov (United States)

Rajgarhia, Vineet [Kingsport, TN; Koivuranta, Kari [Helsinki, FI; Penttila, Merja [Helsinki, FI; Ilmen, Marja [Helsinki, FI; Suominen, Pirkko [Maple Grove, MN; Aristidou, Aristos [Maple Grove, MN; Miller, Christopher Kenneth [Cottage Grove, MN; Olson, Stacey [St. Bonifacius, MN; Ruohonen, Laura [Helsinki, FI

2011-05-17

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications', include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetically modified yeast species, and fermentation processes using genetically modified yeast

Science.gov (United States)

Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

2013-05-14

Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

Genetic modification of hematopoietic stem cells with nonviral systems: past progress and future prospects.

Science.gov (United States)

Papapetrou, E P; Zoumbos, N C; Athanassiadou, A

2005-10-01

Serious unwanted complications provoked by retroviral gene transfer into hematopoietic stem cells (HSCs) have recently raised the need for the development and assessment of alternative gene transfer vectors. Within this context, nonviral gene transfer systems are attracting increasing interest. Their main advantages include low cost, ease of handling and large-scale production, large packaging capacity and, most importantly, biosafety. While nonviral gene transfer into HSCs has been restricted in the past by poor transfection efficiency and transient maintenance, in recent years, biotechnological developments are converting nonviral transfer into a realistic approach for genetic modification of cells of hematopoietic origin. Herein we provide an overview of past accomplishments in the field of nonviral gene transfer into hematopoietic progenitor/stem cells and we point at future challenges. We argue that episomally maintained self-replicating vectors combined with physical methods of delivery show the greatest promise among nonviral gene transfer strategies for the treatment of disorders of the hematopoietic system.

Bcl-xL Genetic Modification Enhanced the Therapeutic Efficacy of Mesenchymal Stem Cell Transplantation in the Treatment of Heart Infarction.

Science.gov (United States)

Xue, Xiaodong; Liu, Yu; Zhang, Jian; Liu, Tao; Yang, Zhonglu; Wang, Huishan

2015-01-01

Objectives. Low survival rate of mesenchymal stem cells (MSCs) severely limited the therapeutic efficacy of cell therapy in the treatment of myocardial infarction (MI). Bcl-xL genetic modification might enhance MSC survival after transplantation. Methods. Adult rat bone marrow MSCs were modified with human Bcl-xL gene (hBcl-xL-MSCs) or empty vector (vector-MSCs). MSC apoptosis and paracrine secretions were characterized using flow cytometry, TUNEL, and ELISA in vitro. In vivo, randomized adult rats with MI received myocardial injections of one of the three reagents: hBcl-xL-MSCs, vector-MSCs, or culture medium. Histochemistry, TUNEL, and echocardiography were carried out to evaluate cell engraftment, apoptosis, angiogenesis, scar formation, and cardiac functional recovery. Results. In vitro, cell apoptosis decreased 43%, and vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and plate-derived growth factor (PDGF) increased 1.5-, 0.7-, and 1.2-fold, respectively, in hBcl-xL-MSCs versus wild type and vector-MSCs. In vivo, cell apoptosis decreased 40% and 26% in hBcl-xL-MSC group versus medium and vector-MSC group, respectively. Similar results were observed in cell engraftment, angiogenesis, scar formation, and cardiac functional recovery. Conclusions. Genetic modification of MSCs with hBcl-xL gene could be an intriguing strategy to improve the therapeutic efficacy of cell therapy in the treatment of heart infarction.

Optimizing viral and non-viral gene transfer methods for genetic modification of porcine mesenchymal stem cells

DEFF Research Database (Denmark)

Stiehler, Maik; Duch, Mogens; Mygind, Tina

2006-01-01

INTRODUCTION: Mesenchymal stem cells (MSCs) provide an excellent source of pluripotent progenitor cells for tissue-engineering applications due to their proliferation capacity and differentiation potential. Genetic modification of MSCs with genes encoding tissue-specific growth factors...... viral and non-viral ex vivo gene delivery systems with respect to gene transfer efficiency, maintenance of transgene expression, and safety issues using primary porcine MSCs as target cells. MATERIALS AND METHODS: MSCs were purified from bone marrow aspirates from the proximal tibiae of four 3-month......-old Danish landrace pigs by Ficoll step gradient separation and polystyrene adherence technique. Vectors expressing enhanced green fluorescent protein (eGFP) and human bone morphogenetic protein-2 (BMP-2) were transferred to the cells by different non-viral methods and by use of recombinant adeno...

A new genetic linkage map of the zygomycete fungus Phycomyces blakesleeanus.

Directory of Open Access Journals (Sweden)

Suman Chaudhary

Full Text Available Phycomyces blakesleeanus is a member of the subphylum Mucoromycotina. A genetic map was constructed from 121 progeny of a cross between two wild type isolates of P. blakesleeanus with 134 markers. The markers were mostly PCR-RFLPs. Markers were located on 46 scaffolds of the genome sequence, covering more than 97% of the genome. Analysis of the alleles in the progeny revealed nine or 12 linkage groups, depending on the log of the odds (LOD score, across 1583.4 cM at LOD 5. The linkage groups were overlaid on previous mapping data from crosses between mutants, aided by new identification of the mutations in primary metabolism mutant strains. The molecular marker map, the phenotype map and the genome sequence are overall congruent, with some exceptions. The new genetic map provides a genome-wide estimate for recombination, with the average of 33.2 kb per cM. This frequency is one piece of evidence for meiosis during zygospore development in Mucoromycotina species. At the same time as meiosis, transmission of non-recombinant chromosomes is also evident in the mating process in Phycomyces. The new map provides scaffold ordering for the genome sequence and a platform upon which to identify the genes in mutants that are affected in traits of interest, such as carotene biosynthesis, phototropism or gravitropism, using positional cloning.

First successful reduction of clinical allergenicity of food by genetic modification: Mal d 1-silenced apples cause fewer allergy symptoms than the wild-type cultivar

DEFF Research Database (Denmark)

Dubois, A. E. J.; Pagliarani, G.; Brouwer, R. M.

2015-01-01

BACKGROUND: Genetic modification of allergenic foods such as apple has the potential to reduce their clinical allergenicity, but this has never been studied by oral challenges in allergic individuals. METHODS: We performed oral food challenges in 21 apple-allergic individuals with Elstar apples...... which had undergone gene silencing of the major allergen of apple, Mal d 1, by RNA interference. Downregulation of Mal d 1 gene expression in the apples was verified by qRT-PCR. Clinical responses to the genetically modified apples were compared to those seen with the wild-type Elstar using a visual...

Genetic demographic networks: Mathematical model and applications.

Science.gov (United States)

Kimmel, Marek; Wojdyła, Tomasz

2016-10-01

Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise

Genetic Diversity in the UV Sex Chromosomes of the Brown Alga Ectocarpus.

Science.gov (United States)

Avia, Komlan; Lipinska, Agnieszka P; Mignerot, Laure; Montecinos, Alejandro E; Jamy, Mahwash; Ahmed, Sophia; Valero, Myriam; Peters, Akira F; Cock, J Mark; Roze, Denis; Coelho, Susana M

2018-06-06

Three types of sex chromosome system exist in nature: diploid XY and ZW systems and haploid UV systems. For many years, research has focused exclusively on XY and ZW systems, leaving UV chromosomes and haploid sex determination largely neglected. Here, we perform a detailed analysis of DNA sequence neutral diversity levels across the U and V sex chromosomes of the model brown alga Ectocarpus using a large population dataset. We show that the U and V non-recombining regions of the sex chromosomes (SDR) exhibit about half as much neutral diversity as the autosomes. This difference is consistent with the reduced effective population size of these regions compared with the rest of the genome, suggesting that the influence of additional factors such as background selection or selective sweeps is minimal. The pseudoautosomal region (PAR) of this UV system, in contrast, exhibited surprisingly high neutral diversity and there were several indications that genes in this region may be under balancing selection. The PAR of Ectocarpus is known to exhibit unusual genomic features and our results lay the foundation for further work aimed at understanding whether, and to what extent, these structural features underlie the high level of genetic diversity. Overall, this study fills a gap between available information on genetic diversity in XY/ZW systems and UV systems and significantly contributes to advancing our knowledge of the evolution of UV sex chromosomes.

Genetic modification of wetland grasses for phytoremediation

Energy Technology Data Exchange (ETDEWEB)

Czako, M.; Liang Dali; Marton, L. [Dept. of Biological Sciences, Univ. of South Carolina, Columbia, SC (United States); Feng Xianzhong; He Yuke [National Lab. of Plant Molecular Genetics, Shanghai Inst. of Plant Physiology, Chinese Academy of Sciences, Shanghai, SH (China)

2005-04-01

Wetland grasses and grass-like monocots are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Tissue culture is prerequisite for genetic manipulation, and methods are reported here for in vitro culture and micropropagation of a number of wetland plants of various ecological requirements such as salt marsh, brackish water, riverbanks, and various zones of lakes and ponds, and bogs. The monocots represent numerous genera in various families such as Poaceae, Cyperaceae, Juncaceae, and Typhaceae. The reported species are in various stages of micropropagation and Arundo donax is scaled for mass propagation for selecting elite lines for pytoremediation. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is also reported here. All but one transgenic lines contained both the organomercurial lyase (merB) and mercuric reductase (merA) sequences showing that co-introduction into Spartina of two genes from separate Agrobacterium strains is possible. (orig.)

Lost in translation: Defects in transfer RNA modifications and neurological disorders

Czech Academy of Sciences Publication Activity Database

Bednářová, Andrea; Hanna, M.; Durham, I.; Van Cleave, T.; England, A.; Chaudhuri, A.; Krishnan, N.

2017-01-01

Roč. 10, MAY 09 (2017), č. článku 135. ISSN 1662-5099 Grant - others:GA ČR(CZ) L200961701 Institutional support: RVO:60077344 Keywords : transfer RNA modifications * modified nucleosides * neurological disease Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 5.076, year: 2016 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5422465/

Biochemical And Genetic Modification Of Polysaccharides

Science.gov (United States)

Kern, Roger G.; Petersen, Gene R.; Richards, Gil F.

1993-01-01

Bacteriophages producing endopolysaccharase-type enzymes used to produce, isolate, and purify high yields of modified polysaccharides from polysaccharides produced by, and incorporated into capsules of, certain bacteria. Bacteriophages used in conversion of native polysaccharide materials into polymers of nearly uniform high molecular weight or, alternatively, into highly pure oligosaccharides. Also used in genetic selection of families of polysaccharides structurally related to native polysaccharide materials, but having altered properties. Resulting new polysaccharides and oligosaccharides prove useful in variety of products, including pharmaceutical chemicals, coating materials, biologically active carbohydrates, and drag-reducing additives for fluids.

Dual targeting of gene delivery by genetic modification of adenovirus serotype 5 fibers and cell-selective transcriptional control.

Science.gov (United States)

Work, L M; Ritchie, N; Nicklin, S A; Reynolds, P N; Baker, A H

2004-08-01

Adenovirus (Ad)-mediated gene delivery is a promising approach for genetic manipulation of the vasculature and is being used in both preclinical models and clinical trials. However, safety concerns relating to infection of nontarget tissue and the poor infectivity of vascular cells compared to other cell types necessitates Ad vector refinement. Here, we combine a transductional targeting approach to improve vascular cell infectivity through RGD peptide insertion into adenovirus fibers, combined with transcriptional targeting to endothelial cells using a approximately 1 kb fragment of the fms-like tyrosine kinase receptor-1 (FLT-1) promoter. Single- and double-modified vectors were characterized in human cell lines that either support or have silenced FLT-1 expression. In rat hepatocytes and endothelial cells, the double modification substantially shifted transduction profiles toward vascular endothelial cells. Furthermore, in intact aortae derived from spontaneously hypertensive rats that display enhanced alphav integrin expression on dysfunctional endothelium, enhanced levels of transduction were observed using the double-modified vector but not in aortae derived from normotensive control rats. Our data indicate that Ad-mediated transduction can be beneficially modified in vitro and in vivo by combining fiber modification and a cell-selective promoter within a single-component vector system.

Bioethics, sport and the genetically enhanced athlete.

Science.gov (United States)

Miah, Andy

2002-01-01

This paper begins by acknowledging the interest taken by various international organisations in genetic enhancement and sport, including the US President's Council on Bioethics (July, 2002) and the World Anti-Doping Agency (March, 2002). It is noticed how sporting organisations have been particularly concerned to emphasize the 'threat' of genetics to sport, whereas other institutions have recognised the broader bioethical issues arising from this prospect, which do not readily reject the use of genetic technology in sport. Sports are identified as necessarily 'human' and 'moral' practices, the exploration of which can reveal greater insight into the intuitive fears about genetic modification. It is argued that anti-doping testing measures and sanctions unacceptably persecute the athlete. While there are substantial reasons to be concerned about the use of genetic modification in sport, the desire for policy ought not diminish the need for ethical research; nor ought such research embody the similar guise of traditional 'anti' doping strategies. Rather, the approach to genetics in sport must be informed more by broader social policies in bioethics and recognition of the greater goods arising from genetic technology.

Genetics & sport: bioethical concerns.

Science.gov (United States)

Miah, Andy

2012-12-01

This paper provides an overview of the ethical issues pertaining to the use of genetic insights and techniques in sport. Initially, it considers a range of scientific findings that have stimulated debate about the ethical issues associated with genetics applied to sport. It also outlines some of the early policy responses to these discoveries from world leading sports organizations, along with knowledge about actual use of gene technologies in sport. Subsequently, it considers the challenges with distinguishing between therapeutic use and human enhancement within genetic science, which is a particularly important issue for the world of sport. Next, particular attention is given to the use of genetic information, which raises questions about the legitimacy and reliability of genetic tests, along with the potential public value of having DNA databanks to economize in health care. Finally, the ethics of gene transfer are considered, inviting questions into the values of sport and humanity. It argues that, while gene modification may seem conceptually similar to other forms of doping, the requirements upon athletes are such that new forms of enhancement become increasingly necessary to discover. Insofar as genetic science is able to create safer, more effective techniques of human modification, then it may be an appealing route through which to modify athletes to safeguard the future of elite sports as enterprises of human excellence.

A genetically diverse but distinct North American population of Sarcocystis neurona includes an overrepresented clone described by 12 microsatellite alleles.

Science.gov (United States)

Asmundsson, Ingrid M; Dubey, J P; Rosenthal, Benjamin M

2006-09-01

The population genetics and systematics of most coccidians remain poorly defined despite their impact on human and veterinary health. Non-recombinant parasite clones characterized by distinct transmission and pathogenesis traits persist in the coccidian Toxoplasma gondii despite opportunities for sexual recombination. In order to determine whether this may be generally true for tissue-cyst forming coccidia, and to address evolutionary and taxonomic problems within the genus Sarcocystis, we characterized polymorphic microsatellite markers in Sarcocystis neurona, the major causative agent of equine protozoal myeloencephalitis (EPM). Bayesian statistical modeling, phylogenetic reconstruction based on genotypic chord distances, and analyses of linkage disequilibrium were employed to examine the population structure within S. neurona and closely related Sarcocystis falcatula isolates from North and South America. North American S. neurona were clearly differentiated from those of South America and also from isolates of S. falcatula. Although S. neurona is characterized by substantial allelic and genotypic diversity typical of interbreeding populations, one genotype occurs with significantly excessive frequency; thus, some degree of asexual propagation of S. neurona clones may naturally occur. Finally, S. neurona isolated from disparate North American localities and diverse hosts (opossums, a Southern sea otter, and horses) comprise a single genetic population. Isolates associated with clinical neurological disease bear no obvious distinction as measured by these presumably neutral genetic markers.

Application of genetic algorithm with genetic modification and quality map in production strategy optimization; Aplicacao de algoritmo genetico com modificacao genetica e mapa de qualidade na otimizacao de estrategia de producao

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Lincoln; Maschio, Celio; Schiozer, Denis J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia de Petroleo

2008-07-01

The definition of position and number of wells is the most important stage on production strategy selection, since it will affect the reservoir behavior, which influences future decisions. However this process is time-consuming and it is often a trial-and-error approach. Many studies have been made in order to reduce the engineer's effort in this stage, by minimizing the number of simulation runs through proxy models or by automating the whole process, using some optimization algorithm. This work proposes a methodology that integrates genetic algorithm and quality map to automate the production strategy optimization. It is also introduced the concept of genetic modification, which is the procedure to update the quality map according to the wells production of each evaluated strategy. The objective is to improve the evolutionary process, allowing the evaluation of more promising alternatives, improving the chance of obtaining better solutions without a substantial increase in the number of simulations. (author)

Modifications to the HIPAA Privacy, Security, Enforcement, and Breach Notification rules under the Health Information Technology for Economic and Clinical Health Act and the Genetic Information Nondiscrimination Act; other modifications to the HIPAA rules.

Science.gov (United States)

2013-01-25

The Department of Health and Human Services (HHS or ``the Department'') is issuing this final rule to: Modify the Health Insurance Portability and Accountability Act (HIPAA) Privacy, Security, and Enforcement Rules to implement statutory amendments under the Health Information Technology for Economic and Clinical Health Act (``the HITECH Act'' or ``the Act'') to strengthen the privacy and security protection for individuals' health information; modify the rule for Breach Notification for Unsecured Protected Health Information (Breach Notification Rule) under the HITECH Act to address public comment received on the interim final rule; modify the HIPAA Privacy Rule to strengthen the privacy protections for genetic information by implementing section 105 of Title I of the Genetic Information Nondiscrimination Act of 2008 (GINA); and make certain other modifications to the HIPAA Privacy, Security, Breach Notification, and Enforcement Rules (the HIPAA Rules) to improve their workability and effectiveness and to increase flexibility for and decrease burden on the regulated entities.

PLMD: An updated data resource of protein lysine modifications.

Science.gov (United States)

Xu, Haodong; Zhou, Jiaqi; Lin, Shaofeng; Deng, Wankun; Zhang, Ying; Xue, Yu

2017-05-20

Post-translational modifications (PTMs) occurring at protein lysine residues, or protein lysine modifications (PLMs), play critical roles in regulating biological processes. Due to the explosive expansion of the amount of PLM substrates and the discovery of novel PLM types, here we greatly updated our previous studies, and presented a much more integrative resource of protein lysine modification database (PLMD). In PLMD, we totally collected and integrated 284,780 modification events in 53,501 proteins across 176 eukaryotes and prokaryotes for up to 20 types of PLMs, including ubiquitination, acetylation, sumoylation, methylation, succinylation, malonylation, glutarylation, glycation, formylation, hydroxylation, butyrylation, propionylation, crotonylation, pupylation, neddylation, 2-hydroxyisobutyrylation, phosphoglycerylation, carboxylation, lipoylation and biotinylation. Using the data set, a motif-based analysis was performed for each PLM type, and the results demonstrated that different PLM types preferentially recognize distinct sequence motifs for the modifications. Moreover, various PLMs synergistically orchestrate specific cellular biological processes by mutual crosstalks with each other, and we totally found 65,297 PLM events involved in 90 types of PLM co-occurrences on the same lysine residues. Finally, various options were provided for accessing the data, while original references and other annotations were also present for each PLM substrate. Taken together, we anticipated the PLMD database can serve as a useful resource for further researches of PLMs. PLMD 3.0 was implemented in PHP + MySQL and freely available at http://plmd.biocuckoo.org. Copyright © 2017 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

Inhibition of oxygen-glucose deprivation-induced apoptosis of human adipose-derived stem cells by genetic modification with antiapoptotic protein bcl-2.

Science.gov (United States)

Cui, Ziwei; Shen, Liangyun; Lin, Yue; Wang, Shuqin; Zheng, Dongfeng; Tan, Qian

2014-08-01

Adipose-derived stem cells (ADSCs) have become a promising tool for a wide range of cell-based therapies. However, transplanted ADSCs do not survive well under ischemic conditions. In this study we aimed to inhibit oxygen-glucose deprivation (OGD)-induced apoptosis of human ADSCs by genetic modification with antiapoptotic protein Bcl-2. After isolation and culture, the phenotypes of human ADSCs at passage 3 were analyzed by flow cytometry. Then, genetic modification of ADSCs with Bcl-2 was carried out. Bcl-2 gene transfection was verified by Western blot analysis and multipotent differentiation properties were evaluated in Bcl-2-modified ADSCs (Bcl-2-ADSCs). Apoptosis was evaluated by a TUNEL assay under ischemic conditions induced by OGD. Apoptotic nuclei were also assessed and quantified by Hoechst staining. The cultured ADSCs expressed stem cell-associated markers CD29, CD34, CD44, and CD90, but not fibroblast marker HLA-DR or hematopoietic stem cell marker CD133. The Bcl-2 gene was transferred into ADSCs efficiently, and Bcl-2-ADSCs differentiated into adipocytes, chondrocytes, and osteoblasts. In addition, Bcl-2 overexpression reduced the percentage of apoptotic Bcl-2-ADSCs by 38 % under OGD. Our results indicate that Bcl-2 overexpression through gene transfection inhibits apoptosis of ADSCs under ischemic conditions. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Selected topics from classical bacterial genetics.

Science.gov (United States)

Raleigh, Elisabeth A; Elbing, Karen; Brent, Roger

2002-08-01

Current cloning technology exploits many facts learned from classical bacterial genetics. This unit covers those that are critical to understanding the techniques described in this book. Topics include antibiotics, the LAC operon, the F factor, nonsense suppressors, genetic markers, genotype and phenotype, DNA restriction, modification and methylation and recombination.

[Ethical challenges of genetic manipulation and research with animals].

Science.gov (United States)

Rodríguez Yunta, Eduardo

2012-01-01

Research with animals presents ethical questions both for being used as models of human diseases and for being a prerequisite for trials in humans, as in the introduction of genetic modifications. Some of these questions refer to the fact that, as models, they do not fully represent the human condition; that conducting toxicity tests causes great harm to animals; that their nature is altered by genetic modifications and that introducing genetically modified organisms is a risk. The use of animals in research for the benefit of humans imposes the moral responsibility to respect them, not making them suffer unnecessarily, since they are living beings capable of feeling.

Genetic transformation of fruit trees: current status and remaining challenges.

Science.gov (United States)

Gambino, Giorgio; Gribaudo, Ivana

2012-12-01

Genetic transformation has emerged as a powerful tool for genetic improvement of fruit trees hindered by their reproductive biology and their high levels of heterozygosity. For years, genetic engineering of fruit trees has focussed principally on enhancing disease resistance (against viruses, fungi, and bacteria), although there are few examples of field cultivation and commercial application of these transgenic plants. In addition, over the years much work has been performed to enhance abiotic stress tolerance, to induce modifications of plant growth and habit, to produce marker-free transgenic plants and to improve fruit quality by modification of genes that are crucially important in the production of specific plant components. Recently, with the release of several genome sequences, studies of functional genomics are becoming increasingly important: by modification (overexpression or silencing) of genes involved in the production of specific plant components is possible to uncover regulatory mechanisms associated with the biosynthesis and catabolism of metabolites in plants. This review focuses on the main advances, in recent years, in genetic transformation of the most important species of fruit trees, devoting particular attention to functional genomics approaches and possible future challenges of genetic engineering for these species in the post-genomic era.

Laboratory Course on "Streptomyces" Genetics and Secondary Metabolism

Science.gov (United States)

Siitonen, Vilja; Räty, Kaj; Metsä-Ketelä, Mikko

2016-01-01

The "'Streptomyces' genetics and secondary metabolism" laboratory course gives an introduction to the versatile soil dwelling Gram-positive bacteria "Streptomyces" and their secondary metabolism. The course combines genetic modification of "Streptomyces"; growing of the strain and protoplast preparation, plasmid…

Plasmid-based genetic modification of human bone marrow-derived stromal cells: analysis of cell survival and transgene expression after transplantation in rat spinal cord.

Science.gov (United States)

Ronsyn, Mark W; Daans, Jasmijn; Spaepen, Gie; Chatterjee, Shyama; Vermeulen, Katrien; D'Haese, Patrick; Van Tendeloo, Viggo Fi; Van Marck, Eric; Ysebaert, Dirk; Berneman, Zwi N; Jorens, Philippe G; Ponsaerts, Peter

2007-12-14

Bone marrow-derived stromal cells (MSC) are attractive targets for ex vivo cell and gene therapy. In this context, we investigated the feasibility of a plasmid-based strategy for genetic modification of human (h)MSC with enhanced green fluorescent protein (EGFP) and neurotrophin (NT)3. Three genetically modified hMSC lines (EGFP, NT3, NT3-EGFP) were established and used to study cell survival and transgene expression following transplantation in rat spinal cord. First, we demonstrate long-term survival of transplanted hMSC-EGFP cells in rat spinal cord under, but not without, appropriate immune suppression. Next, we examined the stability of EGFP or NT3 transgene expression following transplantation of hMSC-EGFP, hMSC-NT3 and hMSC-NT3-EGFP in rat spinal cord. While in vivo EGFP mRNA and protein expression by transplanted hMSC-EGFP cells was readily detectable at different time points post-transplantation, in vivo NT3 mRNA expression by hMSC-NT3 cells and in vivo EGFP protein expression by hMSC-NT3-EGFP cells was, respectively, undetectable or declined rapidly between day 1 and 7 post-transplantation. Further investigation revealed that the observed in vivo decline of EGFP protein expression by hMSC-NT3-EGFP cells: (i) was associated with a decrease in transgenic NT3-EGFP mRNA expression as suggested following laser capture micro-dissection analysis of hMSC-NT3-EGFP cell transplants at day 1 and day 7 post-transplantation, (ii) did not occur when hMSC-NT3-EGFP cells were transplanted subcutaneously, and (iii) was reversed upon re-establishment of hMSC-NT3-EGFP cell cultures at 2 weeks post-transplantation. Finally, because we observed a slowly progressing tumour growth following transplantation of all our hMSC cell transplants, we here demonstrate that omitting immune suppressive therapy is sufficient to prevent further tumour growth and to eradicate malignant xenogeneic cell transplants. In this study, we demonstrate that genetically modified hMSC lines can survive

Enhanced genetic modification of adult growth factor mobilized peripheral blood hematopoietic stem and progenitor cells with rapamycin.

Science.gov (United States)

Li, Lijing; Torres-Coronado, Mónica; Gu, Angel; Rao, Anitha; Gardner, Agnes M; Epps, Elizabeth W; Gonzalez, Nancy; Tran, Chy-Anh; Wu, Xiwei; Wang, Jin-Hui; DiGiusto, David L

2014-10-01

Genetic modification of adult human hematopoietic stem and progenitor cells (HSPCs) with lentiviral vectors leads to long-term gene expression in the progeny of the HSPCs and has been used to successfully treat several monogenic diseases. In some cases, the gene-modified cells have a selective growth advantage over nonmodified cells and eventually are the dominant engrafted population. However, in disease indications for which the gene-modified cells do not have a selective advantage, optimizing transduction of HSPC is paramount to successful stem cell-based gene therapy. We demonstrate here that transduction of adult CD34+ HSPCs with lentiviral vectors in the presence of rapamycin, a widely used mTORC1 inhibitor, results in an approximately threefold increase in stable gene marking with minimal effects on HSPC growth and differentiation. Using this approach, we have demonstrated that we can enhance the frequency of gene-modified HSPCs that give rise to clonogenic progeny in vitro without excessive increases in the number of vector copies per cell or changes in integration pattern. The genetic marking of HSPCs and expression of transgenes is durable, and transplantation of gene-modified HSPCs into immunodeficient mice results in high levels of gene marking of the lymphoid and myeloid progeny in vivo. The prior safe clinical history of rapamycin in other applications supports the use of this compound to generate gene-modified autologous HSPCs for our HIV gene therapy clinical trials. ©AlphaMed Press.

Epigenetic modifications in prostate cancer.

Science.gov (United States)

Ngollo, Marjolaine; Dagdemir, Aslihan; Karsli-Ceppioglu, Seher; Judes, Gaelle; Pajon, Amaury; Penault-Llorca, Frederique; Boiteux, Jean-Paul; Bignon, Yves-Jean; Guy, Laurent; Bernard-Gallon, Dominique J

2014-01-01

Prostate cancer is the most common cancer in men and the second leading cause of cancer deaths in men in France. Apart from the genetic alterations in prostate cancer, epigenetics modifications are involved in the development and progression of this disease. Epigenetic events are the main cause in gene regulation and the three most epigenetic mechanisms studied include DNA methylation, histone modifications and microRNA expression. In this review, we summarized epigenetic mechanisms in prostate cancer. Epigenetic drugs that inhibit DNA methylation, histone methylation and histone acetylation might be able to reactivate silenced gene expression in prostate cancer. However, further understanding of interactions of these enzymes and their effects on transcription regulation in prostate cancer is needed and has become a priority in biomedical research. In this study, we summed up epigenetic changes with emphasis on pharmacologic epigenetic target agents.

Determinants of consumer attitudes and purchase intentions with regard to genetically modified foods: Results of a cross-national survey

DEFF Research Database (Denmark)

Bredahl, Lone

2000-01-01

purchasing the products, which were, in turn, significantly influenced by overall attitudes towards genetic modification in food production through their effects on beliefs that consumer hold about the quality and trustworthiness of the products. 6. The results clearly verify that consumer acceptance...... the results of a survey which was carried out in Denmark, Germany, Italy and the United Kingdom to investigate the formation of consumer attitudes towards genetic modification in food production and of purchase decisions with regard to genetically modified yoghurt and beer. Altogether, 2031 consumers were...... towards nature and attitude towards technology. These general attitudes were found to influence attitudes towards genetic modification through their impact on perceived risks and benefits of the technology. In Denmark, Germany and the United Kingdom, perceived risks of applying genetic modification...

Safety assessment considerations for food and feed derived from plants with genetic modifications that modulate endogenous gene expression and pathways.

Science.gov (United States)

Kier, Larry D; Petrick, Jay S

2008-08-01

The current globally recognized comparative food and feed safety assessment paradigm for biotechnology-derived crops is a robust and comprehensive approach for evaluating the safety of both the inserted gene product and the resulting crop. Incorporating many basic concepts from food safety, toxicology, nutrition, molecular biology, and plant breeding, this approach has been used effectively by scientists and regulatory agencies for 10-15 years. Current and future challenges in agriculture include the need for improved yields, tolerance to biotic and abiotic stresses, and improved nutrition. The next generation of biotechnology-derived crops may utilize regulatory proteins, such as transcription factors that modulate gene expression and/or endogenous plant pathways. In this review, we discuss the applicability of the current safety assessment paradigm to biotechnology-derived crops developed using modifications involving regulatory proteins. The growing literature describing the molecular biology underlying plant domestication and conventional breeding demonstrates the naturally occurring genetic variation found in plants, including significant variation in the classes, expression, and activity of regulatory proteins. Specific examples of plant modifications involving insertion or altered expression of regulatory proteins are discussed as illustrative case studies supporting the conclusion that the current comparative safety assessment process is appropriate for these types of biotechnology-developed crops.

Acceptance of genetically modified foods: the relation between technology and evaluation.

Science.gov (United States)

Tenbült, Petra; De Vries, Nanne K; van Breukelen, Gerard; Dreezens, Ellen; Martijn, Carolien

2008-07-01

This study investigates why consumers accept different genetically modified food products to different extents. The study shows that whether food products are genetically modified or not and whether they are processed or not are the two important features that affect the acceptance of food products and their evaluation (in terms of perceived healthiness, naturalness, necessity and tastiness). The extent to which these evaluation attributes and acceptance of a product are affected by genetic modification or processing depends on whether the product is negatively affected by the other technology: Any technological change to a 'natural' product (when nonprocessed products are genetically modified or when non-genetically modified products are processed) affect evaluation and acceptance stronger than a change to an technologically adapted product (when processed products are also genetically modified or vice versa). Furthermore, evaluation attributes appear to mediate the effects of genetic modification and processing on acceptance.

Ancient DNA reveals genetic connections between early Di-Qiang and Han Chinese.

Science.gov (United States)

Li, Jiawei; Zeng, Wen; Zhang, Ye; Ko, Albert Min-Shan; Li, Chunxiang; Zhu, Hong; Fu, Qiaomei; Zhou, Hui

2017-12-04

Ancient Di-Qiang people once resided in the Ganqing region of China, adjacent to the Central Plain area from where Han Chinese originated. While gene flow between the Di-Qiang and Han Chinese has been proposed, there is no evidence to support this view. Here we analyzed the human remains from an early Di-Qiang site (Mogou site dated ~4000 years old) and compared them to other ancient DNA across China, including an early Han-related site (Hengbei site dated ~3000 years old) to establish the underlying genetic relationship between the Di-Qiang and ancestors of Han Chinese. We found Mogou mtDNA haplogroups were highly diverse, comprising 14 haplogroups: A, B, C, D (D*, D4, D5), F, G, M7, M8, M10, M13, M25, N*, N9a, and Z. In contrast, Mogou males were all Y-DNA haplogroup O3a2/P201; specifically one male was further assigned to O3a2c1a/M117 using targeted unique regions on the non-recombining region of the Y-chromosome. We compared Mogou to 7 other ancient and 38 modern Chinese groups, in a total of 1793 individuals, and found that Mogou shared close genetic distances with Taojiazhai (a more recent Di-Qiang population), Hengbei, and Northern Han. We modeled their interactions using Approximate Bayesian Computation, and support was given to a potential admixture of ~13-18% between the Mogou and Northern Han around 3300-3800 years ago. Mogou harbors the earliest genetically identifiable Di-Qiang, ancestral to the Taojiazhai, and up to ~33% paternal and ~70% of its maternal haplogroups could be found in present-day Northern Han Chinese.

Modification of genetic effect of gamma-irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1983-01-01

The effect of direct current of different polarity on genetic sequels of #betta#-radiation of Vicia faba seedlings is studied. It is established that weak current might modify genetic sequels of #betta#-radiation. Protective current effect on irradiated meristem cells of seedlings manifests at negative polarization of the meristem before radiation and at positive polarization-after radiation. Modifying effect of electric current is brought about at the expense of redistribution of anions and cations between the meristem and other root zones

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics. S. R. Bhat. Articles written in Journal of Genetics. Volume 85 Issue 2 August 2006 pp 133-139 Research Article. Homeotic-like modification of stamens to petals is associated with aberrant mitochondrial gene expression in cytoplasmic male sterile Ogura Brassica juncea · Gargi Meur K.

Factors influencing U.S. consumer support for genetic modification to prevent crop disease.

Science.gov (United States)

McComas, Katherine A; Besley, John C; Steinhardt, Joseph

2014-07-01

This study examines support for the genetic modification (GM) of crops in the context of preventing "late blight," a devastating potato and tomato disease that caused the Irish Potato Famine in the 1850s and results in substantial crop loss today. We surveyed U.S. adults who do the primary grocery shopping in their household (n = 859). Half of the respondents were randomly assigned to read a vignette describing late blight before responding to questions about GM, whereas the other half read a vignette about generic crop disease before responding to questions. We also examine how the perceived fairness of decision makers relates to GM support and the perceived legitimacy of GM decision making. We found that disease specificity mattered less to support and legitimacy than the perceived fairness of decision makers. The perceived risks of GM to human and environmental health negatively related to GM support and legitimacy, whereas the perceived benefits (e.g. reduced threats to crops and a more secure food supply) positively related to support and legitimacy. Objective knowledge about GM had a small, negative relationship with legitimacy whereas self-assessed familiarity with GM had a positive relationship. Overall, the results offer additional confirmation of past findings from more localized settings that perceived fairness of decision makers matters to support for GM and underscore the importance of considering how risk managers' behaviors and actions are perceived alongside individuals' perceptions about the risks and benefits. Copyright © 2014 Elsevier Ltd. All rights reserved.

An investigation of genetic algorithms

International Nuclear Information System (INIS)

Douglas, S.R.

1995-04-01

Genetic algorithms mimic biological evolution by natural selection in their search for better individuals within a changing population. they can be used as efficient optimizers. This report discusses the developing field of genetic algorithms. It gives a simple example of the search process and introduces the concept of schema. It also discusses modifications to the basic genetic algorithm that result in species and niche formation, in machine learning and artificial evolution of computer programs, and in the streamlining of human-computer interaction. (author). 3 refs., 1 tab., 2 figs

Epigenetic Modifications of Major Depressive Disorder

Directory of Open Access Journals (Sweden)

Kathleen Saavedra

2016-08-01

Full Text Available Major depressive disorder (MDD is a chronic disease whose neurological basis and pathophysiology remain poorly understood. Initially, it was proposed that genetic variations were responsible for the development of this disease. Nevertheless, several studies within the last decade have provided evidence suggesting that environmental factors play an important role in MDD pathophysiology. Alterations in epigenetics mechanism, such as DNA methylation, histone modification and microRNA expression could favor MDD advance in response to stressful experiences and environmental factors. The aim of this review is to describe genetic alterations, and particularly altered epigenetic mechanisms, that could be determinants for MDD progress, and how these alterations may arise as useful screening, diagnosis and treatment monitoring biomarkers of depressive disorders.

Mediation and modification of genetic susceptibility to obesity by eating behaviors.

Science.gov (United States)

de Lauzon-Guillain, Blandine; Clifton, Emma Ad; Day, Felix R; Clément, Karine; Brage, Soren; Forouhi, Nita G; Griffin, Simon J; Koudou, Yves Akoli; Pelloux, Véronique; Wareham, Nicholas J; Charles, Marie-Aline; Heude, Barbara; Ong, Ken K

2017-10-01

Background: Many genetic variants show highly robust associations with body mass index (BMI). However, the mechanisms through which genetic susceptibility to obesity operates are not well understood. Potentially modifiable mechanisms, including eating behaviors, are of particular interest to public health. Objective: Here we explore whether eating behaviors mediate or modify genetic susceptibility to obesity. Design: Genetic risk scores for BMI (BMI-GRSs) were calculated for 3515 and 2154 adults in the Fenland and EDEN (Etude des déterminants pré et postnatals de la santé et du développement de l'enfant) population-based cohort studies, respectively. The eating behaviors-emotional eating, uncontrolled eating, and cognitive restraint-were measured through the use of a validated questionnaire. The mediating effect of each eating behavior on the association between the BMI-GRS and measured BMI was assessed by using the Sobel test. In addition, we tested for interactions between each eating behavior and the BMI-GRS on BMI. Results: The association between the BMI-GRS and BMI was mediated by both emotional eating (EDEN: P- Sobel = 0.01; Fenland: P- Sobel = 0.02) and uncontrolled eating (EDEN: P- Sobel = 0.04; Fenland: P -Sobel = 0.0006) in both sexes combined. Cognitive restraint did not mediate this association ( P -Sobel > 0.10), except among EDEN women ( P -Sobel = 0.0009). Cognitive restraint modified the relation between the BMI-GRS and BMI among men (EDEN: P -interaction = 0.0001; Fenland: P -interaction = 0.04) and Fenland women ( P -interaction = 0.0004). By tertiles of cognitive restraint, the association between the BMI-GRS and BMI was strongest in the lowest tertile of cognitive restraint, and weakest in the highest tertile. Conclusions: Genetic susceptibility to obesity was partially mediated by the "appetitive" eating behavior traits (uncontrolled and emotional eating) and, in 3 of the 4 population groups studied, was modified by cognitive restraint

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Keywords. cytosine methylation; DNA methylation mechanisms; DNA demethylation mechanisms; Darwinian-cum-Lamarckian evolution; epialleles; epigenetic modifications; genetic recombination; heritable induced defence; mutational hotspots; transgenerational inheritance.

Persistence of antigen is required to maintain transplantation tolerance induced by genetic modification of bone marrow stem cells.

Science.gov (United States)

Tian, C; Bagley, J; Iacomini, J

2006-09-01

Genetic modification of hematopoietic stem cells (HSCs) resulting in a state of molecular chimerism can be used to induce donor-specific tolerance to allografts. However, the requirements for maintaining tolerance in molecular chimeras remain unknown. Here, we examined whether long-term expression of a retrovirally encoded alloantigen in hematopoietic cells is required to maintain donor-specific tolerance in molecular chimeras. To this end, mice were reconstituted with syngeneic bone marrow transduced with retroviruses carrying the gene encoding the allogeneic MHC class I molecule Kb. Following induction of molecular chimerism, mice were depleted of cells expressing Kb by administration of the anti-Kb monoclonal antibody Y-3. Mice that were effectively depleted of cells expressing the retrovirally encoded MHC class I antigen rejected Kb disparate skin allografts. In contrast, control molecular chimeras accepted Kb disparate skin allografts indefinitely. These data suggest maintenance of tolerance in molecular chimeras requires long-term expression of retrovirally transduced alloantigen on the progeny of retrovirally transduced HSCs.

Irradiation influence on the detection of genetic-modified soybeans

International Nuclear Information System (INIS)

Villavicencio, A.L.C.H.; Araujo, M.M.; Baldasso, J.G.; Aquino, S.; Konietzny, U.; Greiner, R.

2004-01-01

Three soybean varieties were analyzed to evaluate the irradiation influence on the detection of genetic modification. Samples were treated in a 60 Co facility at dose levels of 0, 500, 800, and 1000 Gy. The seeds were at first analyzed by Comet Assay as a rapid screening irradiation detection method. Secondly, germination test was performed to detect the viability of irradiated soybeans. Finally, because of its high sensitivity, its specificity and rapidity the polimerase chain reaction was the method applied for genetic modified organism detection. The analysis of DNA by the single technique of microgel electrophoresis of single cells (DNA Comet Assay) showed that DNA damage increased with increasing radiation doses. No negative influence of irradiation on the genetic modification detection was found

Genome editing and genetic engineering in livestock for advancing agricultural and biomedical applications.

Science.gov (United States)

Telugu, Bhanu P; Park, Ki-Eun; Park, Chi-Hun

2017-08-01

Genetic modification of livestock has a longstanding and successful history, starting with domestication several thousand years ago. Modern animal breeding strategies predominantly based on marker-assisted and genomic selection, artificial insemination, and embryo transfer have led to significant improvement in the performance of domestic animals, and are the basis for regular supply of high quality animal derived food. However, the current strategy of breeding animals over multiple generations to introduce novel traits is not realistic in responding to the unprecedented challenges such as changing climate, pandemic diseases, and feeding an anticipated 3 billion increase in global population in the next three decades. Consequently, sophisticated genetic modifications that allow for seamless introgression of novel alleles or traits and introduction of precise modifications without affecting the overall genetic merit of the animal are required for addressing these pressing challenges. The requirement for precise modifications is especially important in the context of modeling human diseases for the development of therapeutic interventions. The animal science community envisions the genome editors as essential tools in addressing these critical priorities in agriculture and biomedicine, and for advancing livestock genetic engineering for agriculture, biomedical as well as "dual purpose" applications.

Regeneration ability and genetic transformation of root type chicory ...

African Journals Online (AJOL)

This simple, efficient and reproducible protocol could be useful for inducing somaclonal variation and genetic modification of root chicory cultivars to broaden genetic variation and transferring of important genes. Keywords: Chicory, regeneration, transformation, 1-Naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), ...

Genetic variation and epigenetic modification of the prodynorphin gene in peripheral blood cells in alcoholism.

Science.gov (United States)

D'Addario, Claudio; Shchetynsky, Klementy; Pucci, Mariangela; Cifani, Carlo; Gunnar, Agneta; Vukojević, Vladana; Padyukov, Leonid; Terenius, Lars

2017-06-02

Dynorphins are critically involved in the development, maintenance and relapse of alcoholism. Alcohol-induced changes in the prodynorphin gene expression may be influenced by both gene polymorphisms and epigenetic modifications. The present study of human alcoholics aims to evaluate DNA methylation patterns in the prodynorphin gene (PDYN) promoter and to identify single nucleotide polymorphisms (SNPs) associated with alcohol dependence and with altered DNA methylation. Genomic DNA was isolated from peripheral blood cells of alcoholics and healthy controls, and DNA methylation was studied in the PDYN promoter by bisulfite pyrosequencing. In alcoholics, DNA methylation increased in three of the seven CpG sites investigated, as well as in the average of the seven CpG sites. Data stratification showed lower increase in DNA methylation levels in individuals reporting craving and with higher levels of alcohol consumption. Association with alcoholism was observed for rs2235751 and the presence of the minor allele G was associated with reduced DNA methylation at PDYN promoter in females and younger subjects. Genetic and epigenetic factors within PDYN are related to risk for alcoholism, providing further evidence of its involvement on ethanol effects. These results might be of relevance for developing new biomarkers to predict disease trajectories and therapeutic outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

The Optimal Design Method and Standardized Mathematical Model of Tooth Profile Modification of Spur Gear

Directory of Open Access Journals (Sweden)

Wenjie Mei

2016-01-01

Full Text Available The paper reports a tooth profile modification method of spur gear. After establishing a standardized mathematical model for optimized tooth profile and simulating meshing process with ANSYS finite element analysis, we obtained 625 groups of gear models with different modification parameters. The group with minimum transmission errors owns the optimal parameters. Genetic algorithm was adopted in the entire process for the purpose of reducing the variation of transmission errors in meshing process. The arc and parabolic modification were doing the same processing. After comparing the transmission errors fluctuation produced by the meshing process of gear of nonmodification with arc modification and parabolic modification, we found that the best modification effects of arc modification and parabolic modification were both reduced by 90%. The modification method makes the gear drive process more stable and efficient, and it is also promising in general application for gear drive.

Testing for Genetically Modified Foods Using PCR

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Taylor, Ann; Sajan, Samin

2005-01-01

The polymerase chain reaction (PCR) is a Nobel Prize-winning technique that amplifies a specific segment of DNA and is commonly used to test for the presence of genetic modifications. Students use PCR to test corn meal and corn-muffin mixes for the presence of a promoter commonly used in genetically modified foods, the cauliflower mosaic virus 35S…

Powerful tools for genetic modification: Advances in gene editing.

Science.gov (United States)

Roesch, Erica A; Drumm, Mitchell L

2017-11-01

Recent discoveries and technical advances in genetic engineering, methods called gene or genome editing, provide hope for repairing genes that cause diseases like cystic fibrosis (CF) or otherwise altering a gene for therapeutic benefit. There are both hopes and hurdles with these technologies, with new ideas emerging almost daily. Initial studies using intestinal organoid cultures carrying the common, F508del mutation have shown that gene editing by CRISPR/Cas9 can convert cells lacking CFTR function to cells with normal channel function, providing a precedent that this technology can be harnessed for CF. While this is an important precedent, the challenges that remain are not trivial. A logistical issue for this and many other genetic diseases is genetic heterogeneity. Approximately, 2000 mutations associated with CF have been found in CFTR, the gene responsible for CF, and thus a feasible strategy that would encompass all individuals affected by the disease is particularly difficult to envision. However, single strategies that would be applicable to all subjects affected by CF have been conceived and are being investigated. With all of these approaches, efficiency (the proportion of cells edited), accuracy (how often other sites in the genome are affected), and delivery of the gene editing components to the desired cells are perhaps the most significant, impending hurdles. Our understanding of each of these areas is increasing rapidly, and while it is impossible to predict when a successful strategy will reach the clinic, there is every reason to believe it is a question of "when" and not "if." © 2017 Wiley Periodicals, Inc.

Genetic modification of adeno-associated viral vector type 2 capsid enhances gene transfer efficiency in polarized human airway epithelial cells.

Science.gov (United States)

White, April F; Mazur, Marina; Sorscher, Eric J; Zinn, Kurt R; Ponnazhagan, Selvarangan

2008-12-01

Cystic fibrosis (CF) is a common genetic disease characterized by defects in the expression of the CF transmembrane conductance regulator (CFTR) gene. Gene therapy offers better hope for the treatment of CF. Adeno-associated viral (AAV) vectors are capable of stable expression with low immunogenicity. Despite their potential in CF gene therapy, gene transfer efficiency by AAV is limited because of pathophysiological barriers in these patients. Although a few AAV serotypes have shown better transduction compared with the AAV2-based vectors, gene transfer efficiency in human airway epithelium has still not reached therapeutic levels. To engineer better AAV vectors for enhanced gene delivery in human airway epithelium, we developed and characterized mutant AAV vectors by genetic capsid modification, modeling the well-characterized AAV2 serotype. We genetically incorporated putative high-affinity peptide ligands to human airway epithelium on the GH loop region of AAV2 capsid protein. Six independent mutant AAV were constructed, containing peptide ligands previously reported to bind with high affinity for known and unknown receptors on human airway epithelial cells. The vectors were tested on nonairway cells and nonpolarized and polarized human airway epithelial cells for enhanced infectivity. One of the mutant vectors, with the peptide sequence THALWHT, not only showed the highest transduction in undifferentiated human airway epithelial cells but also indicated significant transduction in polarized cells. Interestingly, this modified vector was also able to infect cells independently of the heparan sulfate proteoglycan receptor. Incorporation of this ligand on other AAV serotypes, which have shown improved gene transfer efficiency in the human airway epithelium, may enhance the application of AAV vectors in CF gene therapy.

Improving experimental phases for strong reflections prior to density modification

International Nuclear Information System (INIS)

Uervirojnangkoorn, Monarin; Hilgenfeld, Rolf; Terwilliger, Thomas C.; Read, Randy J.

2013-01-01

A genetic algorithm has been developed to optimize the phases of the strongest reflections in SIR/SAD data. This is shown to facilitate density modification and model building in several test cases. Experimental phasing of diffraction data from macromolecular crystals involves deriving phase probability distributions. These distributions are often bimodal, making their weighted average, the centroid phase, improbable, so that electron-density maps computed using centroid phases are often non-interpretable. Density modification brings in information about the characteristics of electron density in protein crystals. In successful cases, this allows a choice between the modes in the phase probability distributions, and the maps can cross the borderline between non-interpretable and interpretable. Based on the suggestions by Vekhter [Vekhter (2005 ▶), Acta Cryst. D61, 899–902], the impact of identifying optimized phases for a small number of strong reflections prior to the density-modification process was investigated while using the centroid phase as a starting point for the remaining reflections. A genetic algorithm was developed that optimizes the quality of such phases using the skewness of the density map as a target function. Phases optimized in this way are then used in density modification. In most of the tests, the resulting maps were of higher quality than maps generated from the original centroid phases. In one of the test cases, the new method sufficiently improved a marginal set of experimental SAD phases to enable successful map interpretation. A computer program, SISA, has been developed to apply this method for phase improvement in macromolecular crystallography

Chemical Strategies for the Covalent Modification of Filamentous Phage

Directory of Open Access Journals (Sweden)

Matthew B Francis

2014-12-01

Full Text Available Historically filamentous bacteriophage have been known to be the workhorse of phage display due to their ability to link genotype to phenotype. More recently, the filamentous phage scaffold has proved to be powerful outside the realms of phage display technology in fields such as molecular imaging, cancer research and materials and vaccine development. The ability of the virion to serve as a platform for a variety of applications heavily relies on the functionalization of the phage coat proteins with a wide variety of functionalities. Genetic modification of the coat proteins has been the most widely used strategy for functionalizing the virion; however complementary chemical modification strategies can help to diversify the range of materials that can be developed. This review emphasizes the recent advances that have been made in the chemical modification of filamentous phage as well as some of the challenges that are involved functionalizing the virion.

HMCan-diff: a method to detect changes in histone modifications in cells with different genetic characteristics

KAUST Repository

Ashoor, Haitham; Louis-Brennetot, Caroline; Janoueix-Lerosey, Isabelle; Bajic, Vladimir B.; Boeva, Valentina

2016-01-01

Comparing histone modification profiles between cancer and normal states, or across different tumor samples, can provide insights into understanding cancer initiation, progression and response to therapy. ChIP-seq histone modification data of cancer

Commodifying animals: ethical issues in genetic engineering of animals.

Science.gov (United States)

Almond, B

2000-03-01

The genetic modification of living beings raises special ethical concerns which go beyond general discussion of animal rights or welfare. Although the goals may be similar, biotechnology has accelerated the process of modification of types traditionally carried out by cross-breeding. These changes are discussed in relation to two areas: biomedicine, and animal husbandry. Alternative ethical approaches are reviewed, and it is argued that the teleological thesis underlying virtue ethics has special relevance here. The case for and the case against genetic engineering and patenting of life-forms are examined, and conclusions are drawn which favour regulation, caution and respect for animals and animal species.

Virus vector-mediated genetic modification of brain tumor stromal cells after intravenous delivery.

Science.gov (United States)

Volak, Adrienn; LeRoy, Stanley G; Natasan, Jeya Shree; Park, David J; Cheah, Pike See; Maus, Andreas; Fitzpatrick, Zachary; Hudry, Eloise; Pinkham, Kelsey; Gandhi, Sheetal; Hyman, Bradley T; Mu, Dakai; GuhaSarkar, Dwijit; Stemmer-Rachamimov, Anat O; Sena-Esteves, Miguel; Badr, Christian E; Maguire, Casey A

2018-05-16

The malignant primary brain tumor, glioblastoma (GBM) is generally incurable. New approaches are desperately needed. Adeno-associated virus (AAV) vector-mediated delivery of anti-tumor transgenes is a promising strategy, however direct injection leads to focal transgene spread in tumor and rapid tumor division dilutes out the extra-chromosomal AAV genome, limiting duration of transgene expression. Intravenous (IV) injection gives widespread distribution of AAV in normal brain, however poor transgene expression in tumor, and high expression in non-target cells which may lead to ineffective therapy and high toxicity, respectively. Delivery of transgenes encoding secreted, anti-tumor proteins to tumor stromal cells may provide a more stable and localized reservoir of therapy as they are more differentiated than fast-dividing tumor cells. Reactive astrocytes and tumor-associated macrophage/microglia (TAMs) are stromal cells that comprise a large portion of the tumor mass and are associated with tumorigenesis. In mouse models of GBM, we used IV delivery of exosome-associated AAV vectors driving green fluorescent protein expression by specific promoters (NF-κB-responsive promoter and a truncated glial fibrillary acidic protein promoter), to obtain targeted transduction of TAMs and reactive astrocytes, respectively, while avoiding transgene expression in the periphery. We used our approach to express the potent, yet toxic anti-tumor cytokine, interferon beta, in tumor stroma of a mouse model of GBM, and achieved a modest, yet significant enhancement in survival compared to controls. Noninvasive genetic modification of tumor microenvironment represents a promising approach for therapy against cancers. Additionally, the vectors described here may facilitate basic research in the study of tumor stromal cells in situ.

Possible modification of Alzheimer's disease by statins in midlife: interactions with genetic and non-genetic risk factors.

Science.gov (United States)

Shinohara, Mitsuru; Sato, Naoyuki; Shimamura, Munehisa; Kurinami, Hitomi; Hamasaki, Toshimitsu; Chatterjee, Amarnath; Rakugi, Hiromi; Morishita, Ryuichi

2014-01-01

The benefits of statins, commonly prescribed for hypercholesterolemia, in treating Alzheimer's disease (AD) have not yet been fully established. A recent randomized clinical trial did not show any therapeutic effects of two statins on cognitive function in AD. Interestingly, however, the results of the Rotterdam study, one of the largest prospective cohort studies, showed reduced risk of AD in statin users. Based on the current understanding of statin actions and AD pathogenesis, it is still worth exploring whether statins can prevent AD when administered decades before the onset of AD or from midlife. This review discusses the possible beneficial effects of statins, drawn from previous clinical observations, pathogenic mechanisms, which include β-amyloid (Aβ) and tau metabolism, genetic and non-genetic risk factors (apolipoprotein E, cholesterol, sex, hypertension, and diabetes), and other clinical features (vascular dysfunction and oxidative and inflammatory stress) of AD. These findings suggest that administration of statins in midlife might prevent AD in late life by modifying genetic and non-genetic risk factors for AD. It should be clarified whether statins inhibit Aβ accumulation, tau pathological features, and brain atrophy in humans. To answer this question, a randomized controlled study using amyloid positron emission tomography (PET), tau-PET, and magnetic resonance imaging would be useful. This clinical evaluation could help us to overcome this devastating disease.

Tropism-Modification Strategies for Targeted Gene Delivery Using Adenoviral Vectors

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Andrew H. Baker

2010-10-01

Full Text Available Achieving high efficiency, targeted gene delivery with adenoviral vectors is a long-standing goal in the field of clinical gene therapy. To achieve this, platform vectors must combine efficient retargeting strategies with detargeting modifications to ablate native receptor binding (i.e. CAR/integrins/heparan sulfate proteoglycans and “bridging” interactions. “Bridging” interactions refer to coagulation factor binding, namely coagulation factor X (FX, which bridges hepatocyte transduction in vivo through engagement with surface expressed heparan sulfate proteoglycans (HSPGs. These interactions can contribute to the off-target sequestration of Ad5 in the liver and its characteristic dose-limiting hepatotoxicity, thereby significantly limiting the in vivo targeting efficiency and clinical potential of Ad5-based therapeutics. To date, various approaches to retargeting adenoviruses (Ad have been described. These include genetic modification strategies to incorporate peptide ligands (within fiber knob domain, fiber shaft, penton base, pIX or hexon, pseudotyping of capsid proteins to include whole fiber substitutions or fiber knob chimeras, pseudotyping with non-human Ad species or with capsid proteins derived from other viral families, hexon hypervariable region (HVR substitutions and adapter-based conjugation/crosslinking of scFv, growth factors or monoclonal antibodies directed against surface-expressed target antigens. In order to maximize retargeting, strategies which permit detargeting from undesirable interactions between the Ad capsid and components of the circulatory system (e.g. coagulation factors, erythrocytes, pre-existing neutralizing antibodies, can be employed simultaneously. Detargeting can be achieved by genetic ablation of native receptor-binding determinants, ablation of “bridging interactions” such as those which occur between the hexon of Ad5 and coagulation factor X (FX, or alternatively, through the use of polymer

Infectious diseases: Surveillance, genetic modification and simulation

Science.gov (United States)

Koh, H. L.; Teh, S.Y.; De Angelis, D. L.; Jiang, J.

2011-01-01

Infectious diseases such as influenza and dengue have the potential of becoming a worldwide pandemic that may exert immense pressures on existing medical infrastructures. Careful surveillance of these diseases, supported by consistent model simulations, provides a means for tracking the disease evolution. The integrated surveillance and simulation program is essential in devising effective early warning systems and in implementing efficient emergency preparedness and control measures. This paper presents a summary of simulation analysis on influenza A (H1N1) 2009 in Malaysia. This simulation analysis provides insightful lessons regarding how disease surveillance and simulation should be performed in the future. This paper briefly discusses the controversy over the experimental field release of genetically modified (GM) Aedes aegypti mosquito in Malaysia. Model simulations indicate that the proposed release of GM mosquitoes is neither a viable nor a sustainable control strategy. ?? 2011 WIT Press.

m6ASNP: a tool for annotating genetic variants by m6A function.

Science.gov (United States)

Jiang, Shuai; Xie, Yubin; He, Zhihao; Zhang, Ya; Zhao, Yuli; Chen, Li; Zheng, Yueyuan; Miao, Yanyan; Zuo, Zhixiang; Ren, Jian

2018-04-02

Large-scale genome sequencing projects have identified many genetic variants for diverse diseases. A major goal of these projects is to characterize these genetic variants to provide insight into their function and roles in diseases. N6-methyladenosine (m6A) is one of the most abundant RNA modifications in eukaryotes. Recent studies have revealed that aberrant m6A modifications are involved in many diseases. In this study, we present a user-friendly web server called "m6ASNP" that is dedicated to the identification of genetic variants targeting m6A modification sites. A random forest model was implemented in m6ASNP to predict whether the methylation status of a m6A site is altered by the variants surrounding the site. In m6ASNP, genetic variants in a standard VCF format are accepted as the input data, and the output includes an interactive table containing the genetic variants annotated by m6A function. In addition, statistical diagrams and a genome browser are provided to visualize the characteristics and annotate the genetic variants. We believe that m6ASNP is a highly convenient tool that can be used to boost further functional studies investigating genetic variants. The web server "m6ASNP" is implemented in JAVA and PHP and is freely available at http://m6asnp.renlab.org.

Natural variation of histone modification and its impact on gene expression in the rat genome

Czech Academy of Sciences Publication Activity Database

Rintisch, C.; Heinig, M.; Bauerfeind, A.; Schafer, S.; Mieth, Ch.; Patone, G.; Hummel, O.; Chen, W.; Cook, S.; Cuppen, E.; Colomé-Tatché, M.; Johannes, F.; Jansen, R. C.; Neil, H.; Werner, M.; Pravenec, Michal; Vingron, M.; Hubner, N.

2014-01-01

Roč. 24, JUN (2014), s. 942-953 ISSN 1088-9051 R&D Projects: GA MŠk(CZ) 7E10067; GA ČR(CZ) GAP301/10/0290; GA MŠk(CZ) LL1204 Institutional support: RVO:67985823 Keywords : ChIP-seq * histone modification * gene expression * genetic linkage analysis Subject RIV: EB - Genetic s ; Molecular Biology Impact factor: 14.630, year: 2014

Impact of literacy and numeracy on motivation for behavior change after diabetes genetic risk testing.

Science.gov (United States)

Vassy, Jason L; O'Brien, Kelsey E; Waxler, Jessica L; Park, Elyse R; Delahanty, Linda M; Florez, Jose C; Meigs, James B; Grant, Richard W

2012-01-01

Type 2 diabetes genetic risk testing might motivate at-risk patients to adopt diabetes prevention behaviors. However, the influence of literacy and numeracy on patient response to diabetes genetic risk is unknown. The authors investigated the association of health literacy, genetic literacy, and health numeracy with patient responses to diabetes genetic risk. and Measurements Overweight patients at high phenotypic risk for type 2 diabetes were recruited for a clinical trial of diabetes genetic risk testing. At baseline, participants predicted how their motivation for lifestyle modification to prevent diabetes might change in response to hypothetical scenarios of receiving "high" and "low" genetic risk results. Responses were analyzed according to participants' health literacy, genetic literacy, and health numeracy. Two-thirds (67%) of participants (n = 175) reported very high motivation to prevent diabetes. Despite high health literacy (92% at high school level), many participants had limited health numeracy (30%) and genetic literacy (38%). Almost all (98%) reported that high-risk genetic results would increase their motivation for lifestyle modification. In contrast, response to low-risk genetic results varied. Higher levels of health literacy (P = 0.04), genetic literacy (P = 0.02), and health numeracy (P = 0.02) were associated with an anticipated decrease in motivation for lifestyle modification in response to low-risk results. While patients reported that high-risk genetic results would motivate them to adopt healthy lifestyle changes, response to low-risk results varied by patient numeracy and literacy. However, anticipated responses may not correlate with true behavior change. If future research justifies the clinical use of genetic testing to motivate behavior change, it may be important to assess how patient characteristics modify that motivational effect.

Microsatellites and agronomic traits for assessing genetic ...

African Journals Online (AJOL)

GRACE

2006-05-16

May 16, 2006 ... genetic relationships among 18 New Rice for Africa. (NERICA) varieties .... but two other modifications were later included as described in the discussion ..... markers and their application in wheat breeding: a review. Plant.

Breeding technique of Anastrepha fraterculus (Wied.) for genetic studies

International Nuclear Information System (INIS)

Manso, F.

1999-01-01

Various samples of Anastrepha fraterculus from different areas in Argentina were obtained to develop artificial breeding in the laboratory. Based on a modification of Salles's method, an improved artificial rearing of the species was developed with satisfactory results for genetic analysis. The advances made will contribute towards the search for genetic mechanisms for control. (author)

Review: Biological imprinting: Some genetic considerations | Saad ...

African Journals Online (AJOL)

... as for interpretation of possible mechanisms implicated in its occurrence. Keywords: Genetic imprinting; Mutations; Re-sense mutation; Epigenetic alterations; DNA methylation/demethylation; Parthenogenesis; Position-effect variegation; Post-fertilization genomic imprinting; microRNA; Chromatin modifications; Pyknons ...

Detection of the genetically modified organisms from food products/ Detecţia organismelor modificate genetic din produse alimentare

Directory of Open Access Journals (Sweden)

Curticăpean Manuela

2014-09-01

Full Text Available Încă de la apariţia primelor culturi modificate genetic, oamenii de ştiinţă au avut păreri pro şi contra asupra cultivării si utilizării lor, datorită potenţialelor riscuri pe care le pot avea asupra sănătăţii şi mediului înconjurător. Legislaţia europeană actuală (Directiva 2003/18/CE prevede obligativitatea informării publicului, a monitorizării efectelor pe termen lung, a etichetării şi trasabilităţii în toate stadiile introducerii pe piaţă a OMG. Scopul acestui studiu a fost evaluarea calitativă a produselor alimentare existente pe piaţă, în ceea ce priveşte detecţia prezenţei/ absenţei OMG. În acest sens au fost analizate două tipuri de făină de porumb şi patru tipuri de produse din soia, în perioada 2013. Kit-ul utilizat pentru detecţia prezenţei/absenţei OMG în probele testate, cuprinde etape de izolare ADN, amplificare ADN prin PCR şi electroforeza în gel de agaroză a produşilor amplificaţi şi foloseşte două secvenţe asociate OMG - promotorul 35S şi terminatorul NOS de la Agrobacterium tumefaciens. În urma studiului, au fost pozitive în ceea ce priveşte prezenţa OMG, o probă de mălai extra şi o probă de soia. Rezultatele obţinute ilustrează necesitatea efectuării de analize suplimentare pentru identificarea tipului exact de OMG şi pentru stabilirea cantităţii de OMG (pragul limită impus de legislaţia europeană fiind de 0,9% la nivel de ingredient.

"It just goes against the grain." Public understandings of genetically modified (GM) food in the UK.

Science.gov (United States)

Shaw, Alison

2002-07-01

This paper reports on one aspect of qualitative research on public understandings of food risks, focusing on lay understandings of genetically modified (GM) food in the UK context. A range of theoretical, conceptual, and empirical literature on food, risk, and the public understanding of science are reviewed. The fieldwork methods are outlined and empirical data from a range of lay groups are presented. Major themes include: varying "technical" knowledge of science, the relationship between knowledge and acceptance of genetic modification, the uncertainty of scientific knowledge, genetic modification as inappropriate scientific intervention in "nature", the acceptability of animal and human applications of genetic modification, the appropriate boundaries of scientific innovation, the necessity for GM foods, the uncertainty of risks in GM food, fatalism about avoiding risks, and trust in "experts" to manage potential risks in GM food. Key discussion points relating to a sociological understanding of public attitudes to GM food are raised and some policy implications are highlighted.

Genetic modifications of established varieties of potato through mutagenesis

International Nuclear Information System (INIS)

Brown, C.R.

1984-01-01

Owing to the high intercrossability of improved clones with primitive cultivars and many wild species there is little justification for use of induced mutations in potato to increase variability per se. Modification of certain traits while leaving the genotype basically intact is a promising use of mutagenesis in potato. The successful curing of defects in clones will depend on the establishment a priori of three principles. First, the clones undergoing mutagenesis should be well established varieties tolerant or resistant to the major biotic and abiotic stresses in the area of cultivation. The yield and culinary quality should also be considered high. Second, there should exist some indication that the variation desired is induceable, either through reports of natural intra-clone variation or previous mutagenesis studies. Third, initial screening should be done in virus-free materials

The genetics of radiation-induced osteosarcoma

International Nuclear Information System (INIS)

Rosemann, M.; Kuosaite, V.; Nathrath, M.; Atkinson, M.J.

2002-01-01

Individual genetic variation can influence susceptibility to the carcinogenic effects of many environmental carcinogens. In radiation-exposed populations those individuals with a greater genetically determined susceptibility would be at greater risk of developing cancer. To include this modification of risk into radiation protection schemes it is necessary to identify the genes responsible for determining individual sensitivity. Alpha-particle-induced osteosarcoma in the mouse has been adopted as a model of human radiation carcinogenesis, and genome-wide screens have been conducted for allelic imbalance and genetic linkage. These studies have revealed a series of genes involved in determining the sensitivity to radiogenic osteosarcoma formation. (author)

Artificial Metalloenzymes through Chemical Modification of Engineered Host Proteins

KAUST Repository

Zernickel, Anna

2014-10-01

With a few exceptions, all organisms are restricted to the 20 canonical amino acids for ribosomal protein biosynthesis. Addition of new amino acids to the genetic code can introduce novel functionalities to proteins, broadening the diversity of biochemical as well as chemical reactions and providing new tools to study protein structure, reactivity, dynamics and protein-protein-interactions. The site directed in vivo incorporation developed by P. G. SCHULTZ and coworkers, using an archeal orthogonal tRNA/aaRS (aminoacyl-tRNA synthase) pair, allows site-specifically insertion of a synthetic unnatural amino acid (UAA) by reprogramming the amber TAG stop codon. A variety of over 80 different UAAs can be introduced by this technique. However by now a very limited number can form kinetically stable bonds to late transition metals. This thesis aims to develop new catalytically active unnatural amino acids or strategies for a posttranslational modification of site-specific amino acids in order to achieve highly enantioselective metallorganic enzyme hybrids (MOEH). As a requirement a stable protein host has to be established, surviving the conditions for incorporation, posttranslational modification and the final catalytic reactions. mTFP* a fluorescent protein was genetically modified by excluding any exposed Cys, His and Met forming a variant mTFP*, which fulfills the required specifications. Posttranslational chemical modification of mTFP* allow the introduction of single site metal chelating moieties. For modification on exposed cysteines different maleiimid containing ligand structures were synthesized. In order to perform copper catalyzed click reactions, suitable unnatural amino acids (para-azido-(L)-phenylalanine, para-ethynyl-(L)-phenylalanine) were synthesized and a non-cytotoxic protocol was established. The triazole ring formed during this reaction may contribute as a moderate σ-donor/π-acceptor ligand to the metal binding site. Since the cell limits the

Do genetic modifications in crops affect soil fungi? a review

NARCIS (Netherlands)

Hannula, S.E.; Boer, de W.; Veen, van J.A.

2014-01-01

The use of genetically modified (GM) plants in agriculture has been a topic in public debate for over a decade. Despite their potential to increase yields, there may be unintended negative side-effects of GM plants on soil micro-organisms that are essential for functioning of agro-ecosystems. Fungi

Genetic Engineering of Energy Crops to Reduce Recalcitrance and Enhance Biomass Digestibility

Directory of Open Access Journals (Sweden)

Monika Yadav

2018-06-01

Full Text Available Bioenergy, biofuels, and a range of valuable chemicals may be extracted from the abundantly available lignocellulosic biomass. To reduce the recalcitrance imposed by the complex cell wall structure, genetic engineering has been proposed over the years as a suitable solution to modify the genes, thereby, controlling the overall phenotypic expression. The present review provides a brief description of the plant cell wall structure and its compositional array i.e., lignin, cellulose, hemicellulose, wall proteins, and pectin, along with their effect on biomass digestibility. Also, this review discusses the potential to increase biomass by gene modification. Furthermore, the review highlights the potential genes associated with the regulation of cell wall structure, which can be targeted for achieving energy crops with desired phenotypes. These genetic approaches provide a robust and assured method to bring about the desired modifications in cell wall structure, composition, and characteristics. Ultimately, these genetic modifications pave the way for achieving enhanced biomass yield and enzymatic digestibility of energy crops, which is crucial for maximizing the outcomes of energy crop breeding and biorefinery applications.

[Genetically modified food--unnecessary controversy?].

Science.gov (United States)

Tchórz, Michał; Radoniewicz-Chagowska, Anna; Lewandowska-Stanek, Hanna; Szponar, Elzbieta; Szponar, Jarosław

2012-01-01

Fast development of genetic engineering and biotechnology allows use of genetically modified organisms (GMO) more and more in different branches of science and economy. Every year we can see an increase of food amount produced with the use of modification of genetic material. In our supermarkets we can find brand new types of plants, products including genetically modified ingredients or meat from animals fed with food containing GMO. This article presents general information about genetically modified organisms, it also explains the range of genetic manipulation, use of newly developed products and current field area for GMO in the world. Based on scientific data the article presents benefits from development of biotechnology in reference to modified food. It also presents the voice of skeptics who are extremely concerned about the impact of those organisms on human health and natural environment. Problems that appear or can appear as a result of an increase of GMO are very important not only from a toxicologist's or a doctor's point of view but first of all from the point of view of ordinary consumers--all of us.

Global change and genetic diversity

International Nuclear Information System (INIS)

Kremer, Antoine

2000-01-01

Are there grounds for concern as to the impact of global change on the future of European forests? This question is approached from the genetic angle, considering the modifications produced by climate change on the diversity and adaptive potential of forest species. In the absence of experimental data, the answers are derived from a set of arguments based on knowledge of evolutionary mechanisms involved in genetic diversity, the post-glacial history of European forests and lessons drawn from recent introductions of foreign wood species. These arguments entail less pessimistic conclusions than those generally reached for consequences attributed to global change. Even if major changes in composition could occur, past events show that genetic erosion capable of challenging the adaptive potential of species is unlikely. (author)

Chapter VIII. Contributions of propagation techniques and genetic modification to breeding - genetic engineering for disease resistance

Science.gov (United States)

Genetic engineering offers an opportunity to develop flower bulb crops with resistance to fungal, viral, and bacterial pathogens. Several of the flower bulb crops, Lilium spp., Gladiolus, Zantedeschia, Muscari, Hyacinthus, Narcissus, Ornithogalum, Iris, and Alstroemeria, have been transformed with t...

histoneHMM: Differential analysis of histone modifications with broad genomic footprints

Czech Academy of Sciences Publication Activity Database

Heinig, M.; Colomé-Tatché, M.; Taudt, A.; Rintisch, C.; Schafer, S.; Pravenec, Michal; Hubner, N.; Vingron, M.; Johannes, F.

2015-01-01

Roč. 16, Feb 22 (2015), s. 60 ISSN 1471-2105 R&D Projects: GA MŠk(CZ) 7E10067; GA ČR(CZ) GA13-04420S Institutional support: RVO:67985823 Keywords : ChIP - seq * histone modifications * Hidden Markov model * computational biology * differential analysis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.435, year: 2015

Emotional attitudes of young people completing secondary schools towards genetic modification of organisms (GMO) and genetically modified foods (GMF).

Science.gov (United States)

Jurkiewicz, Anna; Zagórski, Jerzy; Bujak, Franciszek; Lachowski, Stanisław; Florek-Łuszczki, Magdalena

2014-01-01

The objective of the study was recognition of the opinions of adolescents completing secondary schools concerning genetically modified organisms and genetically modified food, especially the respondents' emotional attitude towards scientific achievements in the area of live genetically modified organisms. The study covered a group of 500 school adolescents completing secondary school at the level of maturity examination. The study was conducted by the method of a diagnostic survey using a self-designed questionnaire form. Knowledge concerning the possible health effects of consumption of food containing GMO among adolescents competing secondary schools is on a relatively low level; the adolescents examined 'know rather little' or 'very little know' about this problem. In respondents' opinions the results of reliable studies pertaining to the health effects of consumption of GMO 'rather do not exist'. The respondents are against the cultivation of GM plants and breeding of GM animals on own farm in the future. Secondary school adolescents considered that the production of genetically modified food means primarily the enrichment of biotechnological companies, higher income for food producers, and not the elimination of hunger in the world or elimination of many diseases haunting humans.

Genetic engineering including superseding microinjection: new ways to make GM pigs.

Science.gov (United States)

Galli, Cesare; Perota, Andrea; Brunetti, Dario; Lagutina, Irina; Lazzari, Giovanna; Lucchini, Franco

2010-01-01

Techniques for genetic engineering of swine are providing genetically modified animals of importance for the field of xenotransplantation, animal models for human diseases and for a variety of research applications. Many of these modifications have been directed toward avoiding naturally existing cellular and antibody responses to species-specific antigens. A number of techniques are today available to engineering the genome of mammals, these range from the well established less efficient method of DNA microinjection into the zygote, the use of viral vectors, to the more recent use of somatic cell nuclear transfer. The use of enzymatic engineering that are being developed now will refine the precision of the genetic modification combined with the use of new vectors like transposons. The use of somatic cell nuclear transfer is currently the most efficient way to generate genetically modified pigs. The development of enzymatic engineering with zinc-finger nucleases, recombinases and transposons will revolutionize the field. Nevertheless, genetic engineering in large domesticated animals will remain a challenging task. Recent improvements in several fields of cell and molecular biology offer new promises and opportunities toward an easier, cost-effective and efficient generation of transgenic pigs. © 2010 John Wiley & Sons A/S.

Emotional attitudes of young people completing secondary schools towards genetic modification of organisms (GMO and genetically modified foods (GMF

Directory of Open Access Journals (Sweden)

Anna Jurkiewicz

2014-03-01

Full Text Available Objective. The objective of the study was recognition of the opinions of adolescents completing secondary schools concerning genetically modified organisms and genetically modified food, especially the respondents’ emotional attitude towards scientific achievements in the area of live genetically modified organisms. Material and method. The study covered a group of 500 school adolescents completing secondary school at the level of maturity examination. The study was conducted by the method of a diagnostic survey using a self-designed questionnaire form. Results. Knowledge concerning the possible health effects of consumption of food containing GMO among adolescents competing secondary schools is on a relatively low level; the adolescents examined ‘know rather little’ or ‘very little know’ about this problem. In respondents’ opinions the results of reliable studies pertaining to the health effects of consumption of GMO ‘rather do not exist’. The respondents are against the cultivation of GM plants and breeding of GM animals on own farm in the future. Secondary school adolescents considered that the production of genetically modified food means primarily the enrichment of biotechnological companies, higher income for food producers, and not the elimination of hunger in the world or elimination of many diseases haunting humans.

Effects of environmental stressors on histone modifications and their relevance to carcinogenesis: a systematic review.

NARCIS (Netherlands)

Dik, S.; Scheepers, P.T.J.; Godderis, L.

2012-01-01

Carcinogenesis is a complex process involving both genetic and epigenetic mechanisms. The cellular molecular epigenetic machinery, including histone modifications, is associated with changes in gene expression induced by exposure to environmental agents. In this paper, we systematically reviewed

Genetic engineering applied to agriculture has a long row to hoe.

Science.gov (United States)

Miller, Henry I

2018-01-02

In spite of the lack of scientific justification for skepticism about crops modified with molecular techniques of genetic engineering, they have been the most scrutinized agricultural products in human history. The assumption that "genetically engineered" or "genetically modified" is a meaningful - and dangerous - classification has led to excessive and dilatory regulation. The modern molecular techniques are an extension, or refinement, of older, less precise, less predictable methods of genetic modification, but as long as today's activists and regulators remain convinced that so called "GMOs" represent a distinct and dangerous category of research and products, genetic engineering will fall short of its potential.

Heterogeneity of chromatin modifications in testicular spermatocytic seminoma point toward an epigenetically unstable phenotype

DEFF Research Database (Denmark)

Kristensen, Dina Graae; Mlynarska, Olga; Nielsen, John E

2012-01-01

Testicular spermatocytic seminoma (SS) is a rare tumor type predominantly found in elderly men. It is thought to originate from spermatogonia and shows cytological and genetic heterogeneity. In this study, we performed for the first time a comprehensive analysis of epigenetic modifications in a s...

RNA polymerase II transcriptional fidelity control and its functional interplay with DNA modifications

Science.gov (United States)

Xu, Liang; Wang, Wei; Chong, Jenny; Shin, Ji Hyun; Xu, Jun; Wang, Dong

2016-01-01

Accurate genetic information transfer is essential for life. As a key enzyme involved in the first step of gene expression, RNA polymerase II (Pol II) must maintain high transcriptional fidelity while it reads along DNA template and synthesizes RNA transcript in a stepwise manner during transcription elongation. DNA lesions or modifications may lead to significant changes in transcriptional fidelity or transcription elongation dynamics. In this review, we will summarize recent progress towards understanding the molecular basis of RNA Pol II transcriptional fidelity control and impacts of DNA lesions and modifications on Pol II transcription elongation. PMID:26392149

Genetic analysis of female mating recognition between Drosophila ananassae and Drosophila pallidosa: application of interspecific mosaic genome lines.

Science.gov (United States)

Sawamura, Kyoichi; Zhi, Hua; Setoguchi, Koji; Yamada, Hirokazu; Miyo, Takahiro; Matsuda, Muneo; Oguma, Yuzuru

2008-06-01

Drosophila ananassae and Drosophila pallidosa are closely related species that can produce viable and fertile hybrids of both sexes, although strong sexual isolation exists between the two species. Females are thought to discriminate conspecific from heterospecific males based on their courtship songs. The genetic basis of female discrimination behavior was analyzed using isogenic females from interspecific mosaic genome lines that carry homozygous recombinant chromosomes. Multiple regression analysis indicated a highly significant effect of the left arm of chromosome 2 (2L) on the willingness of females to mate with D. ananassae males. Not only 2L but also the left arm of chromosome X (XL) and the right arm of chromosome 3 (3R) had significant effects on the females' willingness to mate with D. pallidosa males. All regions with strong effects on mate choice have chromosome arrangements characterized by species-specific inversions. Heterospecific combinations of 2L and 3R have previously been suggested to cause postzygotic reproductive isolation. Thus, genes involved in premating as well as postmating isolation are located in or near chromosomal inversions. This conclusion is consistent with the recently proposed hypothesis that "speciation genes" accumulate at a higher rate in non-recombining genome regions when species divergence occurs in the presence of gene flow.

Recombination among multiple mitochondrial pseudogenes from a passerine genus

DEFF Research Database (Denmark)

Nielsen, Kirstine Klitgaard; Arctander, P.

2001-01-01

to the observed differences in substitution patterns 58% of the cloned sequences were identified as pseudogenes. Recombination could be traced in 19% of the inferred nuclear pseudogenes, but this figure probably represents a Significant underestimation of the factual recombination events. The nonrecombined...... pseudogenes consisted of multiple haplotypes found to diverge from 1 to 16% from the mitochondrial gene. The number of mitochondrial nuclear copies and their apparent frequent recombination suggest that pseudogenes constitute a serious potential risk in confounding phylogenetic studies and population genetic...

Genetic analysis of maternal and paternal lineages in Kabardian horses by uniparental molecular markers

Directory of Open Access Journals (Sweden)

Aliy-bek D. Khaudov

2018-02-01

Full Text Available Studies of mitochondrial DNA (mtDNA as well as the non-recombining part of the Y chromosome help to understand the origin and distribution of maternal and paternal lineages. The Kabardian horse from Northern Caucasia which is well-known for strength, stamina and endurance in distance riding has a large gap in its breeding documentation especially in the recent past. A 309 bp fragment of the mitochondrial D-loop (156 Kabardian horses and six mutations in Y chromosome (49 Kabardian stallions, respectively, were analyzed to get a better insight into breeding history, phylogenetic relationship to related breeds, maternal and paternal diversity and genetic structure. We found a high mitochondrial diversity represented by 64 D-loop haplotypes out of 14 haplogroups. The most frequent haplogroups were G (19.5%, L (12.3%, Q (11.7%, and B (11.0%. Although these four haplogroups are also frequently found in Asian riding horses (e.g. Buryat, Kirghiz, Mongolian, Transbaikalian, Tuvinian the percentage of the particular haplogroups varies sometimes remarkable. In contrast, the obtained haplogroup pattern from Kabardian horse was more similar to that of breeds reared in the Middle East. No specific haplotype cluster was observed in the phylogenetic tree for Kabardian horses. On Kabardian Y chromosome, two mutations were found leading to three haplotypes with a percentage of 36.7% (haplotype HT1, 38.8% (haplotype HT2 and 24.5% (haplotype HT3, respectively. The high mitochondrial and also remarkable paternal diversity of the Kabardian horse is caused by its long history with a widely spread maternal origin and the introduction of Arabian as well as Thoroughbred influenced stallions for improvement. This high genetic diversity provides a good situation for the ongoing breed development and performance selection as well as avoiding inbreeding.

Oxidative DNA base modifications as factors in carcinogenesis

International Nuclear Information System (INIS)

Olinski, R.; Jaruga, P.; Zastawny, T.H.

1998-01-01

Reactive oxygen species can cause extensive DNA modifications including modified bases. Some of the DNA base damage has been found to possess premutagenic properties. Therefore, if not repaired, it can contribute to carcinogenesis. We have found elevated amounts of modified bases in cancerous and precancerous tissues as compared with normal tissues. Most of the agents used in anticancer therapy are paradoxically responsible for induction of secondary malignancies and some of them may generate free radicals. The results of our experiments provide evidence that exposure of cancer patients to therapeutic doses of ionizing radiation and anticancer drugs cause base modifications in genomic DNA of lymphocytes. Some of these base damages could lead to mutagenesis in critical genes and ultimately to secondary cancers such as leukemias. This may point to an important role of oxidative base damage in cancer initiation. Alternatively, the increased level of the modified base products may contribute to genetic instability and metastatic potential of tumor cells. (author)

Genetic manipulation of structural color in bacterial colonies

DEFF Research Database (Denmark)

Johansen, Villads Egede; Catón, Laura; Hamidjaja, Raditijo

2018-01-01

analysis, we obtained a detailed correlation of how genetic modifications alter structural color in bacterial colonies. Understanding of genotype and phenotype relations in this system opens the way to genetic engineering of on-demand living optical materials, for use as paints and living sensors.......Naturally occurring photonic structures are responsible for the bright and vivid coloration in a large variety of living organisms. Despite efforts to understand their biological functions, development, and complex optical response, little is known of the underlying genes involved...

CAR models: next-generation CAR modifications for enhanced T-cell function

Directory of Open Access Journals (Sweden)

Daniel Abate-Daga

2016-01-01

Full Text Available T cells genetically targeted with a chimeric antigen receptor (CAR to B-cell malignancies have demonstrated tremendous clinical outcomes. With the proof in principle for CAR T cells as a therapy for B-cell malignancies being established, current and future research is being focused on adapting CAR technology to other cancers, as well as enhancing its efficacy and/or safety. The modular nature of the CAR, extracellular antigen-binding domain fused to a transmembrane domain and intracellular T-cell signaling domains, allows for optimization by replacement of the various components. These modifications are creating a whole new class of therapeutic CARs. In this review, we discuss the recent major advances in CAR design and how these modifications will impact its clinical application.

Modifications of the metabolic pathways of lipid and triacylglycerol production in microalgae

Directory of Open Access Journals (Sweden)

Yu Wei-Luen

2011-11-01

Full Text Available Abstract Microalgae have presented themselves as a strong candidate to replace diminishing oil reserves as a source of lipids for biofuels. Here we describe successful modifications of terrestrial plant lipid content which increase overall lipid production or shift the balance of lipid production towards lipid varieties more useful for biofuel production. Our discussion ranges from the biosynthetic pathways and rate limiting steps of triacylglycerol formation to enzymes required for the formation of triacylglycerol containing exotic lipids. Secondarily, we discuss techniques for genetic engineering and modification of various microalgae which can be combined with insights gained from research in higher plants to aid in the creation of production strains of microalgae.

The effect of communicating the genetic risk of cardiometabolic disorders on motivation and actual engagement in preventative lifestyle modification and clinical outcome: a systematic review and meta-analysis of randomised controlled trials.

Science.gov (United States)

Li, Sherly X; Ye, Zheng; Whelan, Kevin; Truby, Helen

2016-09-01

Genetic risk prediction of chronic conditions including obesity, diabetes and CVD currently has limited predictive power but its potential to engage healthy behaviour change has been of immense research interest. We aimed to understand whether the latter is indeed true by conducting a systematic review and meta-analysis investigating whether genetic risk communication affects motivation and actual behaviour change towards preventative lifestyle modification. We included all randomised controlled trials (RCT) since 2003 investigating the impact of genetic risk communication on health behaviour to prevent cardiometabolic disease, without restrictions on age, duration of intervention or language. We conducted random-effects meta-analyses for perceived motivation for behaviour change and clinical changes (weight loss) and a narrative analysis for other outcomes. Within the thirteen studies reviewed, five were vignette studies (hypothetical RCT) and seven were clinical RCT. There was no consistent effect of genetic risk on actual motivation for weight loss, perceived motivation for dietary change (control v. genetic risk group standardised mean difference (smd) -0·15; 95 % CI -1·03, 0·73, P=0·74) or actual change in dietary behaviour. Similar results were observed for actual weight loss (control v. high genetic risk SMD 0·29 kg; 95 % CI -0·74, 1·31, P=0·58). This review found no clear or consistent evidence that genetic risk communication alone either raises motivation or translates into actual change in dietary intake or physical activity to reduce the risk of cardiometabolic disorders in adults. Of thirteen studies, eight were at high or unclear risk of bias. Additional larger-scale, high-quality clinical RCT are warranted.

Au nanocrystals grown on a better-defined one-dimensional tobacco mosaic virus coated protein template genetically modified by a hexahistidine tag

International Nuclear Information System (INIS)

Liu Nan; Zhang Wei; Luo Zhaopeng; Zhai Niu; Zhang Hongfei; Li Zhonghao; Jiang Xingyi; Tang Gangling; Hu Qingyuan; Wang Chong; Tian Dandan

2012-01-01

In this paper, tobacco mosaic virus (TMV) coated protein (CP) was genetically modified by introducing a hexahistidine tag into it for a well-defined one-dimensional template, on which Au nanocrystals (NCs) were grown. The results showed that genetic modification could not only ameliorate the one-dimensional structure of the template, but also improve the growth density of Au NCs on the template. This indicated that genetic modification could be an effective method to modulate the structure of the TMVCP template-based nanocomposites allowing for a broader application of them. (paper)

Modification of genetic effects of gamma radiation by laser radiation

International Nuclear Information System (INIS)

Khotyljova, L.V.; Khokhlova, S.A.; Khokhlov, I.V.

1988-01-01

Full text: Mutants obtained by means of ionizing radiation and chemical mutagens often show low viability and productivity that makes their use in plant breeding difficult. Methods reducing the destructive mutagen action on important functions of plant organism and increasing quality and practical value of induced mutants would be interesting. We believe that one method for increasing efficiency of experimental mutagenesis in plants is the application of laser radiation as a modificator of genetic effects of ionizing radiation and chemical mutagens. Combined exposure of wheat seedlings to a gamma radiation dose of 2 kR and to laser radiation with the wave length of 632.8 nm (power density - 20 mVt/cm 2 , exposure - 30 min.) resulted in reducing the chromosomal aberration percentage from 30.5% in the gamma version to 16.3% in the combined treatment version. A radiosensibilizing effect was observed at additional exposure of gamma irradiated wheat seeds to laser light with the wave length of 441.6 nm where chromosomal aberration percentage increased from 22% in the gamma-irradiation version to 31% in the combined treatment version. By laser radiation it is also possible to normalize mitotic cell activity suppressed by gamma irradiation. Additional seedling irradiation with the light of helium-neon laser (632.8 nm) resulted in recovery of mitotic cell activity from 21% to 62% and increasing the average content of DNA per nucleus by 10%. The influence of only laser radiation on plant variability was also studied and it was shown that irradiation of wheat seeds and seedlings with pulsed and continuous laser light of visible spectrum resulted in phenotypically altered forms in M 2 . Their frequencies was dependent upon power density, dose and radiation wave length. Number of altered forms increased in going from long-wave to short-wave spectrum region. In comparing efficiency of different laser types of pulsed and continuous exposure (dose - 180 J/cm 2 ) 2% of altered

Genetics and epigenetics of rheumatoid arthritis

Science.gov (United States)

Viatte, Sebastien; Plant, Darren; Raychaudhuri, Soumya

2013-01-01

Investigators have made key advances in rheumatoid arthritis (RA) genetics in the past 10 years. Although genetic studies have had limited influence on clinical practice and drug discovery, they are currently generating testable hypotheses to explain disease pathogenesis. Firstly, we review here the major advances in identifying RA genetic susceptibility markers both within and outside of the MHC. Understanding how genetic variants translate into pathogenic mechanisms and ultimately into phenotypes remains a mystery for most of the polymorphisms that confer susceptibility to RA, but functional data are emerging. Interplay between environmental and genetic factors is poorly understood and in need of further investigation. Secondly, we review current knowledge of the role of epigenetics in RA susceptibility. Differences in the epigenome could represent one of the ways in which environmental exposures translate into phenotypic outcomes. The best understood epigenetic phenomena include post-translational histone modifications and DNA methylation events, both of which have critical roles in gene regulation. Epigenetic studies in RA represent a new area of research with the potential to answer unsolved questions. PMID:23381558

Consumers' cognitions with regard to genetically modified foods: Results of a qualitative study in four countries

DEFF Research Database (Denmark)

Bredahl, Lone

1999-01-01

Italy and the United Kingdom. In all four countries, however, genetic modification was associated with unnaturalness and low trustworthiness of the resulting product, independently of whether the genetically modified material was traceable in the product. Moral considerations were voiced as well...

Avian metapneumovirus M2:2 protein inhibits replication in Vero cells: modification facilitates live vaccine development.

Science.gov (United States)

Clubbe, Jayne; Naylor, Clive J

2011-11-28

Throughout the world, avian metapneumovirus (AMPV) infection of subtype A is principally controlled by two live vaccines both derived from UK field strain #8544. Improvements of those vaccines by use of reverse genetics technology was found to be hampered by the inability of #8544 to replicate in the commonly exploited Vero cell based reverse genetics system. A systematic reverse genetics based genome modification of a DNA copy of #8544, employing sequence data from a Vero grown, #8544 derived, live vaccine; was used to determine mutations required to facilitate virus recovery and replication in Vero cells. This identified a single coding substitution in the M2:2 reading frame as responsible. Furthermore, ablation of M2:2 was found to elicit the same outcome. M2:2 sequence analysis of seven AMPVs found Vero cell adaption to be associated with non similar amino acid changes in M2:2. The study shows that M2:2 modification of field virus #8544 will enable research leading to improved vaccines. This may have more general application to other AMPV field strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

[The discussion of the infiltrative model of mathematical knowledge to genetics teaching].

Science.gov (United States)

Liu, Jun; Luo, Pei-Gao

2011-11-01

Genetics, the core course of biological field, is an importance major-basic course in curriculum of many majors related with biology. Due to strong theoretical and practical as well as abstract of genetics, it is too difficult to study on genetics for many students. At the same time, mathematics is one of the basic courses in curriculum of the major related natural science, which has close relationship with the establishment, development and modification of genetics. In this paper, to establish the intrinsic logistic relationship and construct the integral knowledge network and to help students improving the analytic, comprehensive and logistic abilities, we applied some mathematical infiltrative model genetic knowledge in genetics teaching, which could help students more deeply learn and understand genetic knowledge.

Benefits and risks associated with genetically modified food products.

Science.gov (United States)

Kramkowska, Marta; Grzelak, Teresa; Czyżewska, Krystyna

2013-01-01

Scientists employing methods of genetic engineering have developed a new group of living organisms, termed 'modified organisms', which found application in, among others, medicine, the pharmaceutical industry and food distribution. The introduction of transgenic products to the food market resulted in them becoming a controversial topic, with their proponents and contestants. The presented study aims to systematize objective data on the potential benefits and risks resulting from the consumption of transgenic food. Genetic modifications of plants and animals are justified by the potential for improvement of the food situation worldwide, an increase in yield crops, an increase in the nutritional value of food, and the development of pharmaceutical preparations of proven clinical significance. In the opinions of critics, however, transgenic food may unfavourably affect the health of consumers. Therefore, particular attention was devoted to the short- and long-lasting undesirable effects, such as alimentary allergies, synthesis of toxic agents or resistance to antibiotics. Examples arguing for the justified character of genetic modifications and cases proving that their use can be dangerous are innumerable. In view of the presented facts, however, complex studies are indispensable which, in a reliable way, evaluate effects linked to the consumption of food produced with the application of genetic engineering techniques. Whether one backs up or negates transgenic products, the choice between traditional and non-conventional food remains to be decided exclusively by the consumers.

Genetic variation among pelt sheep population using microsatellite ...

African Journals Online (AJOL)

Genetic variation in three Iranian pelt sheep breeds namely: Gray Shiraz, Zandi and Karakul were investigated using fifteen microsatellite loci. Genomic DNA was extracted from 360 blood samples by extraction kits and salting-out procedure with some modifications. The total number of alleles ranged from 6 to12 in loci.

Detection of genetically modified organisms in foods by protein- and DNA-based techniques : bridging the methods

NARCIS (Netherlands)

Duijn, G. van; Biert, R. van; Bleeker-Marcelis, H.; Boeijen, I. van; Adan, A.J.; Jhakrie, S.; Hessing, M.

2002-01-01

According to European Commission (EC) Regulation 1139/98, foods and food ingredients that are to be delivered to the final consumer in which either protein or DNA resulting from genetic modification is present, shall be subject to additional specific labeling requirements. Since 1994, genetically

Genetic Variation and Its Reflection on Posttranslational Modifications in Frequency Clock and Mating Type a-1 Proteins in Sordaria fimicola

OpenAIRE

Arif, Rabia; Akram, Faiza; Jamil, Tazeen; Mukhtar, Hamid; Lee, Siu Fai; Saleem, Muhammad

2017-01-01

Posttranslational modifications (PTMs) occur in all essential proteins taking command of their functions. There are many domains inside proteins where modifications take place on side-chains of amino acids through various enzymes to generate different species of proteins. In this manuscript we have, for the first time, predicted posttranslational modifications of frequency clock and mating type a-1 proteins in Sordaria fimicola collected from different sites to see the effect of environment o...

Electrospray mass spectrometry characterization of post-translational modifications of barley alpha-amylase 1 produced in yeast

DEFF Research Database (Denmark)

Søgaard, M; Andersen, Jens S.; Roepstorff, P

1993-01-01

We have used electrospray mass spectrometry (ESMS) in combination with protein chemistry and genetics to delineate post-translational modifications in yeast of barley alpha-amylase 1 (AMY1), a 45 kD enzyme crucial for production of malt, an important starting material in the manufacture of beer...

Public perceptions of agrifood applications of Genetic modification – A systematic review

NARCIS (Netherlands)

Frewer, L.J.; Lans, van der I.A.; Fischer, A.R.H.; Reinders, M.J.; Menozzi, D.; Zhang, X.Y.; Berg, van den I.; Zimmermann, K.L.

2012-01-01

An extensive literature relating to public perceptions of genetically modified foods applied to agri-food production has been identified through the process of systematic review. Application of systematic review criteria indicated that 335 papers were of appropriate quality or relevance to be

Domesticated, Genetically Engineered, and Wild Plant Relatives Exhibit Unintended Phenotypic Differences: A Comparative Meta-Analysis Profiling Rice, Canola, Maize, Sunflower, and Pumpkin

Directory of Open Access Journals (Sweden)

Alejandra Hernández-Terán

2017-12-01

Full Text Available Agronomic management of plants is a powerful evolutionary force acting on their populations. The management of cultivated plants is carried out by the traditional process of human selection or plant breeding and, more recently, by the technologies used in genetic engineering (GE. Even though crop modification through GE is aimed at specific traits, it is possible that other non-target traits can be affected by genetic modification due to the complex regulatory processes of plant metabolism and development. In this study, we conducted a meta-analysis profiling the phenotypic consequences of plant breeding and GE, and compared modified cultivars with wild relatives in five crops of global economic and cultural importance: rice, maize, canola, sunflower, and pumpkin. For these five species, we analyzed the literature with documentation of phenotypic traits that are potentially related to fitness for the same species in comparable conditions. The information was analyzed to evaluate whether the different processes of modification had influenced the phenotype in such a way as to cause statistical differences in the state of specific phenotypic traits or grouping of the organisms depending on their genetic origin [wild, domesticated with genetic engineering (domGE, and domesticated without genetic engineering (domNGE]. In addition, we tested the hypothesis that, given that transgenic plants are a construct designed to impact, in many cases, a single trait of the plant (e.g., lepidopteran resistance, the phenotypic differences between domGE and domNGE would be either less (or inexistent than between the wild and domesticated relatives (either domGE or domNGE. We conclude that (1 genetic modification (either by selective breeding or GE can be traced phenotypically when comparing wild relatives with their domesticated relatives (domGE and domNGE and (2 the existence and the magnitude of the phenotypic differences between domGE and domNGE of the same crop

Genetic Testing for Respiratory Disease: Are We There Yet?

Directory of Open Access Journals (Sweden)

Peter D Paré

2012-01-01

Full Text Available The human genome project promised a revolution in health care – the development of ‘personalized medicine’, where knowledge of an individual’s genetic code enables the prediction of risk for specific diseases and the potential to alter that risk based on preventive measures and lifestyle modification. The present brief review provides a report card on the progress toward that goal with respect to respiratory disease. Should generalized population screening for genetic risk factors for respiratory disease be instituted? Or not?

Palenque de San Basilio in Colombia: genetic data support an oral history of a paternal ancestry in Congo.

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Ansari-Pour, Naser; Moñino, Yves; Duque, Constanza; Gallego, Natalia; Bedoya, Gabriel; Thomas, Mark G; Bradman, Neil

2016-03-30

The Palenque, a black community in rural Colombia, have an oral history of fugitive African slaves founding a free village near Cartagena in the seventeenth century. Recently, linguists have identified some 200 words in regular use that originate in a Kikongo language, with Yombe, mainly spoken in the Congo region, being the most likely source. The non-recombining portion of the Y chromosome (NRY) and mitochondrial DNA were analysed to establish whether there was greater similarity between present-day members of the Palenque and Yombe than between the Palenque and 42 other African groups (for all individuals,n= 2799) from which forced slaves might have been taken. NRY data are consistent with the linguistic evidence that Yombe is the most likely group from which the original male settlers of Palenque came. Mitochondrial DNA data suggested substantial maternal sub-Saharan African ancestry and a strong founder effect but did not associate Palenque with any particular African group. In addition, based on cultural data including inhabitants' claims of linguistic differences, it has been hypothesized that the two districts of the village (Abajo and Arriba) have different origins, with Arriba founded by men originating in Congo and Abajo by those born in Colombia. Although significant genetic structuring distinguished the two from each other, no supporting evidence for this hypothesis was found. © 2016 The Author(s).

The mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma represents a model for early evolution of sex chromosomes.

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Audrius Menkis

2008-03-01

Full Text Available We combined gene divergence data, classical genetics, and phylogenetics to study the evolution of the mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma. In this species, a large non-recombining region of the mating-type chromosome is associated with a unique fungal life cycle where self-fertility is enforced by maintenance of a constant state of heterokaryosis. Sequence divergence between alleles of 35 genes from the two single mating-type component strains (i.e. the homokaryotic mat A or mat a-strains, derived from one N. tetrasperma heterokaryon (mat A+mat a, was analyzed. By this approach we were able to identify the boundaries and size of the non-recombining region, and reveal insight into the history of recombination cessation. The non-recombining region covers almost 7 Mbp, over 75% of the chromosome, and we hypothesize that the evolution of the mating-type chromosome in this lineage involved two successive events. The first event was contemporaneous with the split of N. tetrasperma from a common ancestor with its outcrossing relative N. crassa and suppressed recombination over at least 6.6 Mbp, and the second was confined to a smaller region in which recombination ceased more recently. In spite of the early origin of the first "evolutionary stratum", genealogies of five genes from strains belonging to an additional N. tetrasperma lineage indicate independent initiations of suppressed recombination in different phylogenetic lineages. This study highlights the shared features between the sex chromosomes found in the animal and plant kingdoms and the fungal mating-type chromosome, despite fungi having no separate sexes. As is often found in sex chromosomes of plants and animals, recombination suppression of the mating-type chromosome of N. tetrasperma involved more than one evolutionary event, covers the majority of the mating-type chromosome and is flanked by distal regions with obligate crossovers.

Enhancing the functional properties of thermophilic enzymes by chemical modification and immobilization.

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Cowan, Don A; Fernandez-Lafuente, Roberto

2011-09-10

The immobilization of proteins (mostly typically enzymes) onto solid supports is mature technology and has been used successfully to enhance biocatalytic processes in a wide range of industrial applications. However, continued developments in immobilization technology have led to more sophisticated and specialized applications of the process. A combination of targeted chemistries, for both the support and the protein, sometimes in combination with additional chemical and/or genetic engineering, has led to the development of methods for the modification of protein functional properties, for enhancing protein stability and for the recovery of specific proteins from complex mixtures. In particular, the development of effective methods for immobilizing large multi-subunit proteins with multiple covalent linkages (multi-point immobilization) has been effective in stabilizing proteins where subunit dissociation is the initial step in enzyme inactivation. In some instances, multiple benefits are achievable in a single process. Here we comprehensively review the literature pertaining to immobilization and chemical modification of different enzyme classes from thermophiles, with emphasis on the chemistries involved and their implications for modification of the enzyme functional properties. We also highlight the potential for synergies in the combined use of immobilization and other chemical modifications. Copyright © 2011 Elsevier Inc. All rights reserved.

When is genetic modification socially acceptable? When used to advance human health through avenues other than food.

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Olynk Widmar, Nicole J; Dominick, S R; Tyner, Wallace E; Ruple, Audrey

2017-01-01

Given the potential for genetic modification (GM) to impact human health, via food and health mechanisms, a greater understanding of the social acceptance of GM is necessary to facilitate improved health outcomes. This analysis sought to quantify U.S. residents' acceptance of GM across five potential uses (grain production, fruit or vegetable production, livestock production, human medicine, and human health, i.e. disease vector control) and provides an in-depth analysis of a timely case study-the Zika virus (ZIKV). The two categories with the highest levels of acceptance for GM use were human medicine (62% acceptance) and human health (68% acceptance); the proportions agreeing with the use of GM for these two categories were statistically different from all other categories. Acceptance of GM in food uses revealed 44% of the sample accepted the use of GM in livestock production while grain production and fruit and vegetable production showed similar levels of agreement with 49% and 48% of responses, respectively. Two variables were significant in all five models predicting GM acceptance; namely, being male and GM awareness. Being male was significant and positive for all models; respondents who reported being male were more likely (than those who reported female) to agree with all five of the uses of GM studied. Those who were reportedly aware of GM mosquito technology were also more likely to agree with all uses of GM technology investigated. The potential relationship between awareness of GM technology uses and acceptance of other uses could help inform rates of acceptance of new technologies by various population segments.

Genetic Mutations and Epigenetic Modifications: Driving Cancer and Informing Precision Medicine

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Coyle, Krysta Mila; Boudreau, Jeanette E.

2017-01-01

Cancer treatment is undergoing a significant revolution from “one-size-fits-all” cytotoxic therapies to tailored approaches that precisely target molecular alterations. Precision strategies for drug development and patient stratification, based on the molecular features of tumors, are the next logical step in a long history of approaches to cancer therapy. In this review, we discuss the history of cancer treatment from generic natural extracts and radical surgical procedures to site-specific and combinatorial treatment regimens, which have incrementally improved patient outcomes. We discuss the related contributions of genetics and epigenetics to cancer progression and the response to targeted therapies and identify challenges and opportunities for the success of precision medicine. The identification of patients who will benefit from targeted therapies is more complex than simply identifying patients whose tumors harbour the targeted aberration, and intratumoral heterogeneity makes it difficult to determine if a precision therapy is successful during treatment. This heterogeneity enables tumors to develop resistance to targeted approaches; therefore, the rational combination of therapeutic agents will limit the threat of acquired resistance to therapeutic success. By incorporating the view of malignant transformation modulated by networks of genetic and epigenetic interactions, molecular strategies will enable precision medicine for effective treatment across cancer subtypes. PMID:28685150

Benefits and risks associated with genetically modified food products

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Marta Kramkowska

2013-09-01

Full Text Available Scientists employing methods of genetic engineering have developed a new group of living organisms, termed ‘modified organisms’, which found application in, among others, medicine, the pharmaceutical industry and food distribution. The introduction of transgenic products to the food market resulted in them becoming a controversial topic, with their proponents and contestants. The presented study aims to systematize objective data on the potential benefits and risks resulting from the consumption of transgenic food. Genetic modifications of plants and animals are justified by the potential for improvement of the food situation worldwide, an increase in yield crops, an increase in the nutritional value of food, and the development of pharmaceutical preparations of proven clinical significance. In the opinions of critics, however, transgenic food may unfavourably affect the health of consumers. Therefore, particular attention was devoted to the short- and long-lasting undesirable effects, such as alimentary allergies, synthesis of toxic agents or resistance to antibiotics. Examples arguing for the justified character of genetic modifications and cases proving that their use can be dangerous are innumerable. In view of the presented facts, however, complex studies are indispensable which, in a reliable way, evaluate effects linked to the consumption of food produced with the application of genetic engineering techniques. Whether one backs up or negates transgenic products, the choice between traditional and non-conventional food remains to be decided exclusively by the consumers.

Adding 'epi-' to behaviour genetics: implications for animal domestication.

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Jensen, Per

2015-01-01

In this review, it is argued that greatly improved understanding of domestication may be gained from extending the field of behaviour genetics to also include epigenetics. Domestication offers an interesting framework of rapid evolutionary changes caused by well-defined selection pressures. Behaviour is an important phenotype in this context, as it represents the primary means of response to environmental challenges. An overview is provided of the evidence for genetic involvement in behavioural control and the presently used methods for finding so-called behaviour genes. This shows that evolutionary changes in behaviour are to a large extent correlated to changes in patterns of gene expression, which brings epigenetics into the focus. This area is concerned with the mechanisms controlling the timing and extent of gene expression, and a lot of focus has been placed on methylation of cytosine in promoter regions, usually associated with genetic downregulation. The review considers the available evidence that environmental input, for example stress, can modify methylation and other epigenetic marks and subsequently affect behaviour. Furthermore, several studies are reviewed, demonstrating that acquired epigenetic modifications can be inherited and cause trans-generational behaviour changes. In conclusion, epigenetics may signify a new paradigm in this respect, as it shows that genomic modifications can be caused by environmental signals, and random mutations in DNA sequence are therefore not the only sources of heritable genetic variation. © 2015. Published by The Company of Biologists Ltd.

Application of Carbon Nanotubes for Plant Genetic Transformation

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Burlaka, Olga M.; Pirko, Yaroslav V.; Yemets, Alla I.; Blume, Yaroslav B.

In this chapter, the current state of using carbon nanotubes (CNTs; single- and multi-walled) that have attracted great interdisciplinary interest in recent decades due to their peculiar properties for genetic transformation of prokaryotic and eukaryotic cells will be enlightened. The covalent and non-covalent surface chemistry for the CNT functionalization with focus on the potential applications of surface modifications in design of biocompatible CNTs will be discussed. The properties of CNTs that are favorable for biotechnological use and current status of technical approaches that allow the increase in biocompatibility and lower nanotoxicity of engineered CNTs will be described. Decisions proposed by non-covalent surface modification of CNTs will be discussed. Existing data concerning mechanisms of CNT cell entry and factors governing toxicity, cellular uptake, intracellular traffic, and biodegradation of CNTs along with bioavailability of molecular cargoes of loaded CNTs will be discussed. Eco-friendly production of water dispersions of biologically functionalized multi-walled and single-walled CNTs for use as nano-vehicles for the DNA delivery in plant genetic transformation of plants will be described. The background, advantages, and problems of using CNTs in developing of novel methods of genetic transformation, including plant genetic transformation, will be highlighted. Special attention will be paid to the limitations of conventional gene transfer techniques and promising features of CNT-based strategies having improved efficacy, reproducibility, and accuracy along with less time consumption. Issues impeding manipulation of CNTs such as entangled bundle formation, low water solubility, inert properties of pristine CNTs, etc., and ways to solve arising tasks will be overviewed.

Establishment of a tamoxifen-inducible Cre-driver mouse strain for widespread and temporal genetic modification in adult mice.

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Ichise, Hirotake; Hori, Akiko; Shiozawa, Seiji; Kondo, Saki; Kanegae, Yumi; Saito, Izumu; Ichise, Taeko; Yoshida, Nobuaki

2016-07-29

Temporal genetic modification of mice using the ligand-inducible Cre/loxP system is an important technique that allows the bypass of embryonic lethal phenotypes and access to adult phenotypes. In this study, we generated a tamoxifen-inducible Cre-driver mouse strain for the purpose of widespread and temporal Cre recombination. The new line, named CM32, expresses the GFPneo-fusion gene in a wide variety of tissues before FLP recombination and tamoxifen-inducible Cre after FLP recombination. Using FLP-recombined CM32 mice (CM32Δ mice) and Cre reporter mouse lines, we evaluated the efficiency of Cre recombination with and without tamoxifen administration to adult mice, and found tamoxifen-dependent induction of Cre recombination in a variety of adult tissues. In addition, we demonstrated that conditional activation of an oncogene could be achieved in adults using CM32Δ mice. CM32Δ;T26 mice, which harbored a Cre recombination-driven, SV40 large T antigen-expressing transgene, were viable and fertile. No overt phenotype was found in the mice up to 3 months after birth. Although they displayed pineoblastomas (pinealoblastomas) and/or thymic enlargement due to background Cre recombination by 6 months after birth, they developed epidermal hyperplasia when administered tamoxifen. Collectively, our results suggest that the CM32Δ transgenic mouse line can be applied to the assessment of adult phenotypes in mice with loxP-flanked transgenes.

Reasonable Foreseeability and Liability in Relation to Genetically Modified Organisms

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Khoury, Lara; Smyth, Stuart

2007-01-01

This article examines problems that may arise when addressing liability resulting from the genetic modification of microbes, animals, and plants. More specifically, it evaluates how uncertainties relating to the outcomes of these biotechnological innovations affect--or may affect--the courts' application of the reasonable foreseeability…

Methods for genetic transformation of filamentous fungi.

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Li, Dandan; Tang, Yu; Lin, Jun; Cai, Weiwen

2017-10-03

Filamentous fungi have been of great interest because of their excellent ability as cell factories to manufacture useful products for human beings. The development of genetic transformation techniques is a precondition that enables scientists to target and modify genes efficiently and may reveal the function of target genes. The method to deliver foreign nucleic acid into cells is the sticking point for fungal genome modification. Up to date, there are some general methods of genetic transformation for fungi, including protoplast-mediated transformation, Agrobacterium-mediated transformation, electroporation, biolistic method and shock-wave-mediated transformation. This article reviews basic protocols and principles of these transformation methods, as well as their advantages and disadvantages.

Modification of genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The effect of direct electric current of different value and polarity on genetic sequences of γ-irradiation of Vicia faba seedlings has been studied. The previously found modifying effect of direct electric current is confirmed. The extent and character of this effect depend on the value and polarity of current as well as time between irradiation and electric effects. Current effect modes having no effect on irradiated seedlings protecting cells from injury and the modes aggravating radiation effect have been found. At certain modes the effects of direct electric current on irradiated seedlings changes in the rearrangement spectrum are observed, particularly the number of bridges is increased

Transgenerational inheritance or resetting of stress-induced epigenetic modifications: two sides of the same coin.

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Tricker, Penny J

2015-01-01

The transgenerational inheritance of stress-induced epigenetic modifications is still controversial. Despite several examples of defense "priming" and induced genetic rearrangements, the involvement and persistence of transgenerational epigenetic modifications is not known to be general. Here I argue that non-transmission of epigenetic marks through meiosis may be regarded as an epigenetic modification in itself, and that we should understand the implications for plant evolution in the context of both selection for and selection against transgenerational epigenetic memory. Recent data suggest that both epigenetic inheritance and resetting are mechanistically directed and targeted. Stress-induced epigenetic modifications may buffer against DNA sequence-based evolution to maintain plasticity, or may form part of plasticity's adaptive potential. To date we have tended to concentrate on the question of whether and for how long epigenetic memory persists. I argue that we should now re-direct our question to investigate the differences between where it persists and where it does not, to understand the higher order evolutionary methods in play and their contribution.

Transgenerational inheritance or resetting of stress-induced epigenetic modifications: two sides of the same coin.

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Penny J Tricker

2015-09-01

Full Text Available The transgenerational inheritance of stress-induced epigenetic modifications is still controversial. Despite several examples of defence ‘priming’ and induced genetic rearrangements, the involvement and persistence of transgenerational epigenetic modifications is not known to be general. Here I argue that non-transmission of epigenetic marks through meiosis may be regarded as an epigenetic modification in itself, and that we should understand the implications for plant evolution in the context of both selection for and selection against transgenerational epigenetic memory. Recent data suggest that both epigenetic inheritance and resetting are mechanistically directed and targeted. Stress-induced epigenetic modifications may buffer against DNA sequence-based evolution to maintain plasticity, or may form part of plasticity’s adaptive potential. To date we have tended to concentrate on the question of whether and for how long epigenetic memory persists. I argue that we should now re-direct our question to investigate the differences between where it persists and where it does not, to understand the higher order evolutionary methods in play and their contribution.

tRNA's wobble decoding of the genome: 40 years of modification.

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Agris, Paul F; Vendeix, Franck A P; Graham, William D

2007-02-09

The genetic code is degenerate, in that 20 amino acids are encoded by 61 triplet codes. In 1966, Francis Crick hypothesized that the cell's limited number of tRNAs decoded the genome by recognizing more than one codon. The ambiguity of that recognition resided in the third base-pair, giving rise to the Wobble Hypothesis. Post-transcriptional modifications at tRNA's wobble position 34, especially modifications of uridine 34, enable wobble to occur. The Modified Wobble Hypothesis proposed in 1991 that specific modifications of a tRNA wobble nucleoside shape the anticodon architecture in such a manner that interactions were restricted to the complementary base plus a single wobble pairing for amino acids with twofold degenerate codons. However, chemically different modifications at position 34 would expand the ability of a tRNA to read three or even four of the fourfold degenerate codons. One foundation of Crick's Wobble Hypothesis was that a near-constant geometry of canonical base-pairing be maintained in forming all three base-pairs between the tRNA anticodon and mRNA codon on the ribosome. In accepting an aminoacyl-tRNA, the ribosome requires maintenance of a specific geometry for the anticodon-codon base-pairing. However, it is the post-transcriptional modifications at tRNA wobble position 34 and purine 37, 3'-adjacent to the anticodon, that pre-structure the anticodon domain to ensure the correct codon binding. The modifications create both the architecture and the stability needed for decoding through restraints on anticodon stereochemistry and conformational space, and through selective hydrogen bonding. A physicochemical understanding of modified nucleoside contributions to the tRNA anticodon domain architecture and its decoding of the genome has advanced RNA world evolutionary theory, the principles of RNA chemistry, and the application of this knowledge to the introduction of new amino acids to proteins.

Genetic and epigenetic control of plant heat responses

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Junzhong eLiu

2015-04-01

Full Text Available Plants have evolved sophisticated genetic and epigenetic regulatory systems to respond quickly to unfavorable environmental conditions such as heat, cold, drought, and pathogen infections. In particular, heat greatly affects plant growth and development, immunity and circadian rhythm, and poses a serious threat to the global food supply. According to temperatures exposing, heat can be usually classified as warm ambient temperature (about 22-27℃, high temperature (27-30℃ and extremely high temperature (37-42℃, also known as heat stress for the model plant Arabidopsis thaliana. The genetic mechanisms of plant responses to heat have been well studied, mainly focusing on elevated ambient temperature-mediated morphological acclimation and acceleration of flowering, modulation of plant immunity and circadian clock by high temperatures, and thermotolerance to heat stress. Recently, great progress has been achieved on epigenetic regulation of heat responses, including DNA methylation, histone modifications, histone variants, ATP-dependent chromatin remodeling, histone chaperones, small RNAs, long non-coding RNAs and other undefined epigenetic mechanisms. These epigenetic modifications regulate the expression of heat-responsive genes and function to prevent heat-related damage. This review focuses on recent progresses regarding the genetic and epigenetic control of heat responses in plants, and pays more attention to the role of the major epigenetic mechanisms in plant heat responses. Further research perspectives are also discussed.

Investigating Novice and Expert Conceptions of Genetically Modified Organisms

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Potter, Lisa M.; Bissonnette, Sarah A.; Knight, Jonathan D.; Tanner, Kimberly D.

2017-01-01

The aspiration of biology education is to give students tools to apply knowledge learned in the classroom to everyday life. Genetic modification is a real-world biological concept that relies on an in-depth understanding of the molecular behavior of DNA and proteins. This study investigated undergraduate biology students' conceptions of…

Something about Genetics in Psychiatry

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Bakir Mehić

2012-11-01

of the brain functioning and connect them with the hereditary basis. An important advantage of the endophenotype evaluation is also, that it can work in small groups of respondents. Endophenotype evaluation includes an assessment of cognitive deficits, EEG abnormalities, and data obtained by the method of neuroimaging. Considering the current cognition about the genetics of psychiatric disorders, especially schizophrenia [2], it can be said that no single gene by itself causes brain dysfunction. Many gene variants that have proved to be risky for psychiatric disorders have also been found in many healthy individuals. Strength of correlation of the detected genetic polymorphisms is estimated to be relatively low. This means: COMT genes’ polymorphisms (catecho-O-methyltransferase, but also many other genes, modulate cognitive functions, but they do not represent the primary cause of disease[3],genetic risk variants for psychiatric disorders are also found in many healthy people,“Strength” of correlation of detected genetic polymorphisms and diseases is estimated as relative. Except for the primary sequence of nucleotides in our genome, there is also likely a hidden genetic code, which does not determine the sequence of amino acids in proteins, but it determines the time when a gene turns on or off (rewrites or not. The problem with this code is that it is more or less changeable. It is because of the modification of the genome (DNA. The modification with metillization of cytosine in CpG dinucleotide turns off the gene, whereas the acetylation of histones alters the structure of chromatin and turns on the genes. Epigenetics studies[4] such modifications of genomes. Epigenetics may explain the large variability of phenotypes in human population, and why monozygotic twins are not quite identical. They do not differ in the sequence of nucleotides in DNA, but they have different modifications of DNA, because they occur and change by the effect of environmental

The influence of natural barriers in shaping the genetic structure of Maharashtra populations.

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Thangaraj, Kumarasamy; Naidu, B Prathap; Crivellaro, Federica; Tamang, Rakesh; Upadhyay, Shashank; Sharma, Varun Kumar; Reddy, Alla G; Walimbe, S R; Chaubey, Gyaneshwer; Kivisild, Toomas; Singh, Lalji

2010-12-20

The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. To address this issue, we have analyzed the mitochondrial DNA (mtDNA) of 185 individuals and NRY (non-recombining region of Y chromosome) of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older) detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations.

Genetically modified plants: Decade of commercial cultivation

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Mladenović-Drinić Snežana

2005-01-01

Full Text Available The year 2005 marks the beginning of the 10th consecutive year of commercial cultivation of genetically modified plants all around the world. The first GM variety of crops appeared on market during 1995 year and from that global area of biotech crops increased to 81 mil hectares in 2004. Genetically modified plant tolerant to herbicides, resistant to insects, improved quality have been developed. The use of GMO, their release into environment cultivation, utilization as food and feed is regulated in the EU by set of directives: 90/220, 2001/18, 2002/53, 1830/2003. Informer Yugoslavia the low about GMO was adopted in may 2001. That law consist of common regulation and it is in accordinance with EU regulation. Detection of genetic modification in seed and food could be done by PCR or ELISA methods.

Does a medical history of hypertension influence disclosing genetic testing results of the risk for salt-sensitive hypertension, in primary care?

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Okayama M

2016-07-01

Full Text Available Masanobu Okayama,1,2 Taro Takeshima,2 Masanori Harada,3 Ryusuke Ae,4 Eiji Kajii2 1Division of Community Medicine and Medical Education, Kobe University Graduate School of Medicine, Kobe, Hyogo, 2Division of Community and Family Medicine, Center for Community Medicine, Jichi Medical University, Shimotsuke, Tochigi, 3Department of Support of Rural Medicine, Yamaguchi Grand Medical Center, Hofu, Yamaguchi, 4Division of Public Health, Center for Community Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan Objective: Disclosing genetic testing results may contribute to the prevention and management of many common diseases. However, whether the presence of a disease influences these effects is unclear. This study aimed to clarify the difference in the effects of disclosing genetic testing results of the risk for developing salt-sensitive hypertension on the behavioral modifications with respect to salt intake in hypertensive and nonhypertensive patients.Methods: A cross-sectional study using a self-administered questionnaire was conducted for outpatients aged >20 years (N=2,237 at six primary care clinics and hospitals in Japan. The main factors assessed were medical histories of hypertension, salt preferences, reduced salt intakes, and behavior modifications for reducing salt intake. Behavioral modifications of participants were assessed using their behavior stages before and after disclosure of the hypothetical genetic testing results. Results: Of the 2,237 participants, 1,644 (73.5% responded to the survey. Of these respondents, 558 (33.9% patients were hypertensive and 1,086 (66.1% were nonhypertensive. After being notified of the result “If with genetic risk”, the nonhypertensive participants were more likely to make positive behavioral modifications compared to the hypertensive patients among all participants and in those aged <65 years (adjusted relative ratio [ad-RR], 1.76; 95% confidence interval, 1.12−2.76 and ad-RR, 1

Genetic affinities between the Yami tribe people of Orchid Island and the Philippine Islanders of the Batanes archipelago

Science.gov (United States)

2011-01-01

Background Yami and Ivatan islanders are Austronesian speakers from Orchid Island and the Batanes archipelago that are located between Taiwan and the Philippines. The paternal genealogies of the Yami tribe from 1962 monograph of Wei and Liu were compared with our dataset of non-recombining Y (NRY) chromosomes from the corresponding families. Then mitochondrial DNA polymorphism was also analyzed to determine the matrilineal relationships between Yami, Ivatan, and other East Asian populations. Results The family relationships inferred from the NRY Phylogeny suggested a low number of paternal founders and agreed with the genealogy of Wei and Liu (P Philippine people was closer than that between Yami and Ivatan, suggesting that the Orchid islanders were colonized separately by their nearest neighbors and bred in isolation. However a northward gene flow to Orchid Island from the Philippines was suspected as Yami and Ivatan peoples both speak Western Malayo-Polynesian languages which are not spoken in Taiwan. Actually, only very little gene flow was observed between Yami and Ivatan or between Yami and the Philippines as indicated by the sharing of mtDNA haplogroup B4a1a4 and one O1a1* Y-STR lineage. Conclusions The NRY and mtDNA genetic information among Yami tribe peoples fitted well the patrilocal society model proposed by Wei and Liu. In this proposal, there were likely few genetic exchanges among Yami and the Philippine people. Trading activities may have contributed to the diffusion of Malayo-Polynesian languages among them. Finally, artifacts dating 4,000 YBP, found on Orchid Island and indicating association with the Out of Taiwan hypothesis might be related to a pioneering stage of settlement, as most dating estimates inferred from DNA variation in our data set ranged between 100-3,000 YBP. PMID:21281460

Genetic modification of T cells improves the effectiveness of adoptive tumor immunotherapy.

Science.gov (United States)

Jakóbisiak, Marek; Gołab, Jakub

2010-10-01

Appropriate combinations of immunotherapy and gene therapy promise to be more effective in the treatment of cancer patients than either of these therapeutic approaches alone. One such treatment is based on the application of patients' cytotoxic T cells, which can be activated, expanded, and genetically engineered to recognize particular tumor-associated antigens (TAAs). Because T cells recognizing TAAs might become unresponsive in the process of tumor development as a result of tumor evasion strategies, immunogenic viral antigens or alloantigens could be used for the expansion of cytotoxic T cells and then redirected through genetic engineering. This therapeutic approach has already demonstrated promising results in melanoma patients and could be used in the treatment of many other tumors. The graft-versus-leukemia, or more generally graft-versus-tumor, reaction based on the application of a donor lymphocyte infusion can also be ameliorated through the incorporation of suicide genes into donor lymphocytes. Such lymphocytes could be safely and more extensively used in tumor patients because they could be eliminated should a severe graft-versus-host reaction develop.

Genetic Modification of Short Rotation Poplar Biomass Feedstock for Efficient Conversion to Ethanol

Energy Technology Data Exchange (ETDEWEB)

Dinus, R.J.

2000-08-30

The Bioenergy Feedstock Development Program, Environmental Sciences Division, Oak Ridge National Laboratory is developing poplars (Populus species and hybrids) as sources of renewable energy, i.e., ethanol. Notable increases in adaptability, volume productivity, and pest/stress resistance have been achieved via classical selection and breeding and intensified cultural practices. Significant advances have also been made in the efficiencies of harvesting and handling systems. Given these and anticipated accomplishments, program leaders are considering shifting some attention to genetically modifying feedstock physical and chemical properties, so as to improve the efficiency with which feedstocks can be converted to ethanol. This report provides an in-depth review and synthesis of opportunities for and feasibilities of genetically modifying feedstock qualities via classical selection and breeding, marker-aided selection and breeding, and genetic transformation. Information was collected by analysis of the literature, with emphasis on that published since 1995, and interviews with prominent scientists, breeders, and growers. Poplar research is well advanced, and literature is abundant. The report therefore primarily reflects advances in poplars, but data from other species, particularly other shortrotation hardwoods, are incorporated to fill gaps. An executive summary and recommendations for research, development, and technology transfer are provided immediately after the table of contents. The first major section of the report describes processes most likely to be used for conversion of poplar biomass to ethanol, the various physical and chemical properties of poplar feedstocks, and how such properties are expected to affect process efficiency. The need is stressed for improved understanding of the impact of change on both overall process and individual process step efficiencies. The second part documents advances in trait measurement instrumentation and methodology

Dealing with an Unconventional Genetic Code in  Mitochondria: The Biogenesis and Pathogenic  Defects of the 5‐Formylcytosine Modification in  Mitochondrial tRNAMet

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Lindsey Van Haute

2017-03-01

Full Text Available Human mitochondria contain their own genome, which uses an unconventional genetic code. In addition to the standard AUG methionine codon, the single mitochondrial tRNA Methionine (mt‐tRNAMet also recognises AUA during translation initiation and elongation. Post‐transcriptional modifications of tRNAs are important for structure, stability, correct folding and aminoacylation as well as decoding. The unique 5‐formylcytosine (f5C modification of position 34 in mt‐tRNAMet has been long postulated to be crucial for decoding of unconventional methionine codons and efficient mitochondrial translation. However, the enzymes responsible for the formation of mitochondrial f5C have been identified only recently. The first step of the f5C pathway consists of methylation of cytosine by NSUN3. This is followed by further oxidation by ABH1. Here, we review the role of f5C, the latest breakthroughs in our understanding of the biogenesis of this unique mitochondrial tRNA modification and its involvement in human disease.

[Chromosome as a chronicler: Genetic dating, historical events, and DNA-genealogic temptation].

Science.gov (United States)

Balanovsky, O P; Zaporozhchenko, V V

2016-07-01

Nonrecombinant portions of the genome, Y chromosome and mitochondrial DNA, are widely used for research on human population gene pools and reconstruction of their history. These systems allow the genetic dating of clusters of emerging haplotypes. The main method for age estimations is ρ statistics, which is an average number of mutations from founder haplotype to all modern-day haplotypes. A researcher can estimate the age of the cluster by multiplying this number by the mutation rate. The second method of estimation, ASD, is used for STR haplotypes of the Y chromosome and is based on the squared difference in the number of repeats. In addition to the methods of calculation, methods of Bayesian modeling assume a new significance. They have greater computational cost and complexity, but they allow obtaining an a posteriori distribution of the value of interest that is the most consistent with experimental data. The mutation rate must be known for both calculation methods and modeling methods. It can be determined either during the analysis of lineages or by providing calibration points based on populations with known formation time. These two approaches resulted in rate estimations for Y-chromosomal STR haplotypes with threefold difference. This contradiction was only recently refuted through the use of sequence data for the complete Y chromosome; “whole-genomic” rates of single nucleotide mutations obtained by both methods are mutually consistent and mark the area of application for different rates of STR markers. An issue even more crucial than that of the rates is correlation of the reconstructed history of the haplogroup (a cluster of haplotypes) and the history of the population. Although the need for distinguishing “lineage history” and “population history” arose in the earliest days of phylogeographic research, reconstructing the population history using genetic dating requires a number of methods and conditions. It is known that population

Genetic transformation of Populus tomentosa to improve salt tolerance

Science.gov (United States)

Ningxia Du; Xin Liu; Yun Li; Shouyi Chen; Jinsong Zhang; Da Ha; Wenguang Deng; Chunkui Sun; Yingzhi Zhang; Paula M Pijut

2012-01-01

Soil salinity can be a limiting factor for productivity in agriculture and forestry. In order to fully utilize saline lands productively in plantation forestry for pulp production, the genetic modification of tree species for salt tolerance may be required. The AhDREB1 gene, a DREB-like transcription factor gene, was transferred into ...

Genetic engineering and chemical conjugation of potato virus X.

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Lee, Karin L; Uhde-Holzem, Kerstin; Fischer, Rainer; Commandeur, Ulrich; Steinmetz, Nicole F

2014-01-01

Here we report the genetic engineering and chemical modification of potato virus X (PVX) for the presentation of various peptides, proteins, and fluorescent dyes, or other chemical modifiers. Three different ways of genetic engineering are described and by these means, peptides are successfully expressed not only when the foot and mouth disease virus (FMDV) 2A sequence or a flexible glycine-serine linker is included, but also when the peptide is fused directly to the PVX coat protein. When larger proteins or unfavorable peptide sequences are presented, a partial fusion via the FMDV 2A sequence is preferable. When these PVX chimeras retain the ability to assemble into viral particles and are thus able to infect plants systemically, they can be utilized to inoculate susceptible plants for isolation of sufficient amounts of virus particles for subsequent chemical modification. Chemical modification is required for the display of nonbiological ligands such as fluorophores, polymers, and small drug compounds. We present three methods of chemical bioconjugation. For direct conjugation of small chemical modifiers to solvent exposed lysines, N-hydroxysuccinimide chemistry can be applied. Bio-orthogonal reactions such as copper-catalyzed azide-alkyne cycloaddition or hydrazone ligation are alternatives to achieve more efficient conjugation (e.g., when working with high molecular weight or insoluble ligands). Furthermore, hydrazone ligation offers an attractive route for the introduction of pH-cleavable cargos (e.g., therapeutic molecules).

Biochemical systems approaches for the analysis of histone modification readout.

Science.gov (United States)

Soldi, Monica; Bremang, Michael; Bonaldi, Tiziana

2014-08-01

Chromatin is the macromolecular nucleoprotein complex that governs the organization of genetic material in the nucleus of eukaryotic cells. In chromatin, DNA is packed with histone proteins into nucleosomes. Core histones are prototypes of hyper-modified proteins, being decorated by a large number of site-specific reversible and irreversible post-translational modifications (PTMs), which contribute to the maintenance and modulation of chromatin plasticity, gene activation, and a variety of other biological processes and disease states. The observations of the variety, frequency and co-occurrence of histone modifications in distinct patterns at specific genomic loci have led to the idea that hPTMs can create a molecular barcode, read by effector proteins that translate it into a specific transcriptional state, or process, on the underlying DNA. However, despite the fact that this histone-code hypothesis was proposed more than 10 years ago, the molecular details of its working mechanisms are only partially characterized. In particular, two questions deserve specific investigation: how the different modifications associate and synergize into patterns and how these PTM configurations are read and translated by multi-protein complexes into a specific functional outcome on the genome. Mass spectrometry (MS) has emerged as a versatile tool to investigate chromatin biology, useful for both identifying and validating hPTMs, and to dissect the molecular determinants of histone modification readout systems. We review here the MS techniques and the proteomics methods that have been developed to address these fundamental questions in epigenetics research, emphasizing approaches based on the proteomic dissection of distinct native chromatin regions, with a critical evaluation of their present challenges and future potential. This article is part of a Special Issue entitled: Molecular mechanisms of histone modification function. Copyright © 2014 Elsevier B.V. All rights reserved.

Epigenetics and Evolution: Transposons and the Stochastic Epigenetic Modification Model

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Sergio Branciamore

2015-04-01

Full Text Available In addition to genetic variation, epigenetic variation and transposons can greatly affect the evolutionary fitnesses landscape and gene expression. Previously we proposed a mathematical treatment of a general epigenetic variation model that we called Stochastic Epigenetic Modification (SEM model. In this study we follow up with a special case, the Transposon Silencing Model (TSM, with, once again, emphasis on quantitative treatment. We have investigated the evolutionary effects of epigenetic changes due to transposon (T insertions; in particular, we have considered a typical gene locus A and postulated that (i the expression level of gene A depends on the epigenetic state (active or inactive of a cis- located transposon element T, (ii stochastic variability in the epigenetic silencing of T occurs only in a short window of opportunity during development, (iii the epigenetic state is then stable during further development, and (iv the epigenetic memory is fully reset at each generation. We develop the model using two complementary approaches: a standard analytical population genetics framework (di usion equations and Monte-Carlo simulations. Both approaches led to similar estimates for the probability of fixation and time of fixation of locus TA with initial frequency P in a randomly mating diploid population of effective size Ne. We have ascertained the e ect that ρ, the probability of transposon Modification during the developmental window, has on the population (species. One of our principal conclusions is that as ρ increases, the pattern of fixation of the combined TA locus goes from "neutral" to "dominant" to "over-dominant". We observe that, under realistic values of ρ, epigenetic Modifications can provide an e cient mechanism for more rapid fixation of transposons and cis-located gene alleles. The results obtained suggest that epigenetic silencing, even if strictly transient (being reset at each generation, can still have signi cant

Integrated screening concept in women with genetic predisposition for breast cancer

International Nuclear Information System (INIS)

Bick, U.

1997-01-01

Breast cancer is in 5% of cases due to a genetic disposition. BRCA1 and BRCA2 are by far the most common breast cancer susceptibility genes. For a woman with a genetic predisposition, the individual risk of developing breast cancer sometime in her life is between 70 and 90%. Compared to the spontaneous forms of breast cancer, woman with a genetic predisposition often develop breast cancer at a much younger age. This is why conventional screening programs on the basis of mammography alone cannot be applied without modification to this high-risk group. In this article, an integrated screening concept for women with genetic prodisposition for breast cancer using breast self-examination, clinical examination, ultrasound, mammography and magnetic resonance imaging is introduced. (orig.) [de

Readiness of adolescents to use genetically modified organisms according to their knowledge and emotional attitude towards GMOs

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Stanisław Lachowski

2017-06-01

Stepwise regression analysis showed that the readiness of adolescents to use genetically modified organisms as food or for the production of pharmaceuticals, the production of GM plants or animals on own farm, depends on an emotional-evaluative attitude towards GMOs, and the level of knowledge concerning the essence of genetic modifications.

Genetically modified organisms in New Zealand and cultural issues

International Nuclear Information System (INIS)

McFarlane, R.; Roberts, M.

2005-01-01

One of the ironies of the current debate in New Zealand about genetic modification is that it highlights the age-old conflict between science and religion, and in so doing demonstrates that modem society is still caught in the dilemma posed by these two views of the world. Two case studies are presented that demonstrate the distance between proponents and opponents of genetic modification (GM), and the difficulty of resolution within the secular-based framework of quantitative risk assessment applied by the Environmental Risk Management Authority (ERMA) and decision-making committees. Alternative frameworks suggested by Maori are beginning to emerge, and along with the results of several government-funded research projects in this area, should make a valuable contribution to a new framework that more equitably incorporates the fundamental principles of both knowledge systems. If this aim is achieved, it will be of considerable interest to other indigenous peoples in the world who are also faced with real and perceived threats to their cultural beliefs and values originating from new biotechnologies. (author)

Reconciling genetic evolution and the associative learning account of mirror neurons through data-acquisition mechanisms.

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Lotem, Arnon; Kolodny, Oren

2014-04-01

An associative learning account of mirror neurons should not preclude genetic evolution of its underlying mechanisms. On the contrary, an associative learning framework for cognitive development should seek heritable variation in the learning rules and in the data-acquisition mechanisms that construct associative networks, demonstrating how small genetic modifications of associative elements can give rise to the evolution of complex cognition.

Genetically Modified Food: Knowledge and Attitude of Teachers and Students

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Mohapatra, Animesh K.; Priyadarshini, Deepika; Biswas, Antara

2010-01-01

The concepts behind the technology of genetic modification of organisms and its applications are complex. A diverse range of opinions, public concern and considerable media interest accompanies the subject. This study explores the knowledge and attitudes of science teachers and senior secondary biology students about the application of a rapidly…

Global genetic diversity of Aedes aegypti.

Science.gov (United States)

Gloria-Soria, Andrea; Ayala, Diego; Bheecarry, Ambicadutt; Calderon-Arguedas, Olger; Chadee, Dave D; Chiappero, Marina; Coetzee, Maureen; Elahee, Khouaildi Bin; Fernandez-Salas, Ildefonso; Kamal, Hany A; Kamgang, Basile; Khater, Emad I M; Kramer, Laura D; Kramer, Vicki; Lopez-Solis, Alma; Lutomiah, Joel; Martins, Ademir; Micieli, Maria Victoria; Paupy, Christophe; Ponlawat, Alongkot; Rahola, Nil; Rasheed, Syed Basit; Richardson, Joshua B; Saleh, Amag A; Sanchez-Casas, Rosa Maria; Seixas, Gonçalo; Sousa, Carla A; Tabachnick, Walter J; Troyo, Adriana; Powell, Jeffrey R

2016-11-01

Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations. © 2016 John Wiley & Sons Ltd.

Global Genetic Diversity of Aedes aegypti

Science.gov (United States)

Gloria-Soria, Andrea; Ayala, Diego; Bheecarry, Ambicadutt; Calderon-Arguedas, Olger; Chadee, Dave D.; Chiappero, Marina; Coetzee, Maureen; Elahee, Khouaildi bin; Fernandez-Salas, Ildefonso; Kamal, Hany A.; Kamgang, Basile; Khater, Emad I. M.; Kramer, Laura D.; Kramer, Vicki; Lopez-Solis, Alma; Lutomiah, Joel; Martins, Ademir; Micieli, Maria Victoria; Paupy, Christophe; Ponlawat, Alongkot; Rahola, Nil; Rasheed, Syed Basit; Richardson, Joshua B.; Saleh, Amag A.; Sanchez-Casas, Rosa Maria; Seixas, Gonçalo; Sousa, Carla A.; Tabachnick, Walter J.; Troyo, Adriana; Powell, Jeffrey R.

2016-01-01

Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti, from 30 countries in six continents and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya) the two subspecies remain genetically distinct whereas in urban settings they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats, and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th Centuries was followed by its introduction to Asia in the late 19th Century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l.. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for methods using genetic modification of populations. PMID:27671732

[Safety assessment of foods derived from genetically modified plants].

Science.gov (United States)

Pöting, A; Schauzu, M

2010-06-01

The placing of genetically modified plants and derived food on the market falls under Regulation (EC) No. 1829/2003. According to this regulation, applicants need to perform a safety assessment according to the Guidance Document of the Scientific Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA), which is based on internationally agreed recommendations. This article gives an overview of the underlying legislation as well as the strategy and scientific criteria for the safety assessment, which should generally be based on the concept of substantial equivalence and carried out in relation to an unmodified conventional counterpart. Besides the intended genetic modification, potential unintended changes also have to be assessed with regard to potential adverse effects for the consumer. All genetically modified plants and derived food products, which have been evaluated by EFSA so far, were considered to be as safe as products derived from the respective conventional plants.

Common genetic variants and modification of penetrance of BRCA2-associated breast cancer

DEFF Research Database (Denmark)

Gaudet, Mia M; Kirchhoff, Tomas; Green, Todd

2010-01-01

The considerable uncertainty regarding cancer risks associated with inherited mutations of BRCA2 is due to unknown factors. To investigate whether common genetic variants modify penetrance for BRCA2 mutation carriers, we undertook a two-staged genome-wide association study in BRCA2 mutation carri...

Common genetic variants and modification of penetrance of BRCA2-associated breast cancer

DEFF Research Database (Denmark)

Gaudet, Mia M; Kirchhoff, Tomas; Green, Todd

2010-01-01

The considerable uncertainty regarding cancer risks associated with inherited mutations of BRCA2 is due to unknown factors. To investigate whether common genetic variants modify penetrance for BRCA2 mutation carriers, we undertook a two-staged genome-wide association study in BRCA2 mutation...

Genetically Modified Food: Knowledge and Attitude of Teachers and Students

Science.gov (United States)

Mohapatra, Animesh K.; Priyadarshini, Deepika; Biswas, Antara

2010-10-01

The concepts behind the technology of genetic modification of organisms and its applications are complex. A diverse range of opinions, public concern and considerable media interest accompanies the subject. This study explores the knowledge and attitudes of science teachers and senior secondary biology students about the application of a rapidly expanding technology, genetic engineering, to food production. The results indicated significant difference in understanding of concepts related with genetically engineered food stuffs between teachers and students. The most common ideas about genetically modified food were that cross bred plants and genetically modified plants are not same, GM organisms are produced by inserting a foreign gene into a plant or animal and are high yielding. More teachers thought that genetically engineered food stuffs were unsafe for the environment. Both teachers and students showed number of misconceptions, for example, the pesticidal proteins produced by GM organisms have indirect effects through bioaccumulation, induces production of allergic proteins, genetic engineering is production of new genes, GM plants are leaky sieves and that transgenes are more likely to introgress into wild species than mutated species. In general, more students saw benefits while teachers were cautious about the advantages of genetically engineered food stuffs.

Roads, interrupted dispersal, and genetic diversity in timber rattlesnakes.

Science.gov (United States)

Clark, Rulon W; Brown, William S; Stechert, Randy; Zamudio, Kelly R

2010-08-01

Anthropogenic habitat modification often creates barriers to animal movement, transforming formerly contiguous habitat into a patchwork of habitat islands with low connectivity. Roadways are a feature of most landscapes that can act as barriers or filters to migration among local populations. Even small and recently constructed roads can have a significant impact on population genetic structure of some species, but not others. We developed a research approach that combines fine-scale molecular genetics with behavioral and ecological data to understand the impacts of roads on population structure and connectivity. We used microsatellite markers to characterize genetic variation within and among populations of timber rattlesnakes (Crotalus horridus) occupying communal hibernacula (dens) in regions bisected by roadways. We examined the impact of roads on seasonal migration, genetic diversity, and gene flow among populations. Snakes in hibernacula isolated by roads had significantly lower genetic diversity and higher genetic differentiation than snakes in hibernacula in contiguous habitat. Genetic-assignment analyses revealed that interruption to seasonal migration was the mechanism underlying these patterns. Our results underscore the sizeable impact of roads on this species, despite their relatively recent construction at our study sites (7 to 10 generations of rattlesnakes), the utility of population genetics for studies of road ecology, and the need for mitigating effects of roads.

The role of non-genetic inheritance in evolutionary rescue: epigenetic buffering, heritable bet hedging and epigenetic traps.

Science.gov (United States)

O'Dea, Rose E; Noble, Daniel W A; Johnson, Sheri L; Hesselson, Daniel; Nakagawa, Shinichi

2016-01-01

Rapid environmental change is predicted to compromise population survival, and the resulting strong selective pressure can erode genetic variation, making evolutionary rescue unlikely. Non-genetic inheritance may provide a solution to this problem and help explain the current lack of fit between purely genetic evolutionary models and empirical data. We hypothesize that epigenetic modifications can facilitate evolutionary rescue through 'epigenetic buffering'. By facilitating the inheritance of novel phenotypic variants that are generated by environmental change-a strategy we call 'heritable bet hedging'-epigenetic modifications could maintain and increase the evolutionary potential of a population. This process may facilitate genetic adaptation by preserving existing genetic variation, releasing cryptic genetic variation and/or facilitating mutations in functional loci. Although we show that examples of non-genetic inheritance are often maladaptive in the short term, accounting for phenotypic variance and non-adaptive plasticity may reveal important evolutionary implications over longer time scales. We also discuss the possibility that maladaptive epigenetic responses may be due to 'epigenetic traps', whereby evolutionarily novel factors (e.g. endocrine disruptors) hack into the existing epigenetic machinery. We stress that more ecologically relevant work on transgenerational epigenetic inheritance is required. Researchers conducting studies on transgenerational environmental effects should report measures of phenotypic variance, so that the possibility of both bet hedging and heritable bet hedging can be assessed. Future empirical and theoretical work is required to assess the relative importance of genetic and epigenetic variation, and their interaction, for evolutionary rescue.

How modification of accessible lysines to phenylalanine modulates the structural and functional properties of horseradish peroxidase: a simulation study.

Directory of Open Access Journals (Sweden)

Leila Navapour

Full Text Available Horseradish Peroxidase (HRP is one of the most studied peroxidases and a great number of chemical modifications and genetic manipulations have been carried out on its surface accessible residues to improve its stability and catalytic efficiency necessary for biotechnological applications. Most of the stabilized derivatives of HRP reported to date have involved chemical or genetic modifications of three surface-exposed lysines (K174, K232 and K241. In this computational study, we altered these lysines to phenylalanine residues to model those chemical modifications or genetic manipulations in which these positively charged lysines are converted to aromatic hydrophobic residues. Simulation results implied that upon these substitutions, the protein structure becomes less flexible. Stability gains are likely to be achieved due to the increased number of stable hydrogen bonds, improved heme-protein interactions and more integrated proximal Ca2+ binding pocket. We also found a new persistent hydrogen bond between the protein moiety (F174 and the heme prosthetic group as well as two stitching hydrogen bonds between the connecting loops GH and F'F″ in mutated HRP. However, detailed analysis of functionally related structural properties and dynamical features suggests reduced reactivity of the enzyme toward its substrates. Molecular dynamics simulations showed that substitutions narrow the bottle neck entry of peroxide substrate access channel and reduce the surface accessibility of the distal histidine (H42 and heme prosthetic group to the peroxide and aromatic substrates, respectively. Results also demonstrated that the area and volume of the aromatic-substrate binding pocket are significantly decreased upon modifications. Moreover, the hydrophobic patch functioning as a binding site or trap for reducing aromatic substrates is shrunk in mutated enzyme. Together, the results of this simulation study could provide possible structural clues to explain

Electrostatic bio-manipulation for the modification of cellular functions

International Nuclear Information System (INIS)

Washizu, Masao

2013-01-01

The use of electrostatic field effects, including field-induced reversible-breakdown of the membrane and dielectrophoresis (DEP), in microfabricated structures are investigated. With the use of field constriction created by a micro-orifice whose diameter is smaller than the cells, controlled magnitude of pulsed voltage can be applied across the cell membrane regardless of the cell size, shape or orientation. As a result, the breakdown occurs reproducibly and with minimal invasiveness. The breakdown is used for two purposes, electroporation by which foreign substances can be fed into cells, and electrofusion which creates genetic and/or cytoplasmic mixture among two cells. When GFP plasmid is fed into MSC cell, the gene expression started within 2 hours, and finally observed in more than 50% of cells. For cell fusion, several ten percent fusion yield is achieved for most cell types, with the colony formation in several percents. Timing-controlled feeding foreign substances or mixing cellular contents, with high-yield and low-invasiveness, is expected to bring about a new technology for both genetic and epigenetic modifications of cellular functions, in such field as regenerative medicine.

Modification effect of Ni-38 wt.%Si on Al-12 wt.%Si alloy

International Nuclear Information System (INIS)

Wu Yuying; Liu Xiangfa; Jiang Binggang; Huang Chuanzhen

2009-01-01

Modification effect of Ni-38 wt.%Si on the Al-12 wt.%Si alloy has been studied by differential scanning calorimeter, torsional oscillation viscometer and liquid X-ray diffraction experiments. It is found that there is a modification effect of Ni-38 wt.%Si on Al-12 wt.%Si alloy, i.e. primary Si can precipitate in the microstructure of Al-12 wt.%Si alloy when Ni and Si added in the form of Ni-38 wt.%Si, but not separately. Ni-38 wt.%Si alloy brings 'genetic materials' into the Al-Si melt, which makes the melt to form more ordering structure, promotes the primary Si precipitated. Moreover, the addition of Ni-38 wt.%Si, which decreases the solidification supercooling degree of Al-12 wt.%Si alloy, is identical to the effect of heterogeneous nuclei.

Modification effect of Ni-38 wt.%Si on Al-12 wt.%Si alloy

Energy Technology Data Exchange (ETDEWEB)

Wu Yuying [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Ji' nan 250061 (China)], E-mail: wyy532001@163.com; Liu Xiangfa [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Ji' nan 250061 (China); Shandong Binzhou Bohai Piston Co., Ltd., Binzhou 256602, Shandong (China); Jiang Binggang [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Ji' nan 250061 (China); Huang Chuanzhen [School of Mechanical Engineering, Shandong University, Jinan 250061 (China)

2009-05-27

Modification effect of Ni-38 wt.%Si on the Al-12 wt.%Si alloy has been studied by differential scanning calorimeter, torsional oscillation viscometer and liquid X-ray diffraction experiments. It is found that there is a modification effect of Ni-38 wt.%Si on Al-12 wt.%Si alloy, i.e. primary Si can precipitate in the microstructure of Al-12 wt.%Si alloy when Ni and Si added in the form of Ni-38 wt.%Si, but not separately. Ni-38 wt.%Si alloy brings 'genetic materials' into the Al-Si melt, which makes the melt to form more ordering structure, promotes the primary Si precipitated. Moreover, the addition of Ni-38 wt.%Si, which decreases the solidification supercooling degree of Al-12 wt.%Si alloy, is identical to the effect of heterogeneous nuclei.

Behavioral and environmental modification of the genetic influence on body mass index: A twin study

Science.gov (United States)

Horn, Erin E.; Turkheimer, Eric; Strachan, Eric; Duncan, Glen E.

2015-01-01

Body mass index (BMI) has a strong genetic basis, with a heritability around 0.75, but is also influenced by numerous behavioral and environmental factors. Aspects of the built environment (e.g., environmental walkability) are hypothesized to influence obesity by directly affecting BMI, by facilitating or inhibiting behaviors such as physical activity that are related to BMI, or by suppressing genetic tendencies toward higher BMI. The present study investigated relative influences of physical activity and walkability on variance in BMI using 5,079 same-sex adult twin pairs (70% monozygotic, 65% female). High activity and walkability levels independently suppressed genetic variance in BMI. Estimating their effects simultaneously, however, suggested that the walkability effect was mediated by activity. The suppressive effect of activity on variance in BMI was present even with a tendency for low-BMI individuals to select into environments that require higher activity levels. Overall, our results point to community- or macro-level interventions that facilitate individual-level behaviors as a plausible approach to addressing the obesity epidemic among U.S. adults. PMID:25894925

First successful reduction of clinical allergenicity of food by genetic modification: Mal d 1-silenced apples cause fewer allergy symptoms than the wild-type cultivar.

Science.gov (United States)

Dubois, A E J; Pagliarani, G; Brouwer, R M; Kollen, B J; Dragsted, L O; Eriksen, F D; Callesen, O; Gilissen, L J W J; Krens, F A; Visser, R G F; Smulders, M J M; Vlieg-Boerstra, B J; Flokstra-de Blok, B J; van de Weg, W E

2015-11-01

Genetic modification of allergenic foods such as apple has the potential to reduce their clinical allergenicity, but this has never been studied by oral challenges in allergic individuals. We performed oral food challenges in 21 apple-allergic individuals with Elstar apples which had undergone gene silencing of the major allergen of apple, Mal d 1, by RNA interference. Downregulation of Mal d 1 gene expression in the apples was verified by qRT-PCR. Clinical responses to the genetically modified apples were compared to those seen with the wild-type Elstar using a visual analogue scale (VAS). Gene silencing produced two genetically modified apple lines expressing Mal d 1.02 and other Mal d 1 gene mRNA levels which were extensively downregulated, that is only 0.1-16.4% (e-DR1) and 0.2-9.9% (e-DR2) of those of the wild-type Elstar, respectively. Challenges with these downregulated apple lines produced significantly less intense maximal symptoms to the first dose (Vmax1) than with Elstar (Vmax1 Elstar 3.0 mm vs 0.0 mm for e-DR1, P = 0.017 and 0.0 mm for e-DR2, P = 0.043), as well as significantly less intense mean symptoms per dose (meanV/d) than with Elstar (meanV/d Elstar 2.2 mm vs 0.2 mm for e-DR1, P = 0.017 and 0.0 mm for e-DR2, P = 0.043). Only one subject (5%) remained symptom-free when challenged with the Elstar apple, whereas 43% did so with e-DR1 and 63% with e-DR2. These data show that mRNA silencing of Mal d 1 results in a marked reduction of Mal d 1 gene expression in the fruit and reduction of symptoms when these apples are ingested by allergic subjects. Approximately half of the subjects developed no symptoms whatsoever, and virtually all subjects wished to consume the apple again in the future. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The influence of natural barriers in shaping the genetic structure of Maharashtra populations.

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Kumarasamy Thangaraj

Full Text Available BACKGROUND: The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue, we have analyzed the mitochondrial DNA (mtDNA of 185 individuals and NRY (non-recombining region of Y chromosome of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. CONCLUSIONS/SIGNIFICANCE: Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations.

A cross-cultural comparison of consumers' purchase intentions with regard to genetically modified foods

DEFF Research Database (Denmark)

Bredahl, Lone

1999-01-01

CONSUMERS' PURCHASE INTENTIONS WITH REGARD TO GENETICALLY MODIFIED FOODS ARE INVESTIGATED THROUGH A CROSS-NATIONAL SURVEY IN DENMARK, GERMANY, GREAT BRITAIN AND ITALY, USING BEER AND YOGHURT AS EXAMPLES (N=1000 PER PRODUCT). RESULTS SHOW THAT GENERALLY COGNITIVE STRUCTURES OF ITALIAN CONSUMERS...... ARE NOT COMPARABLE WITH COGNITIVE STRUCTURES OF CONSUMERS OF THE THREE OTHER COUNTRIES. IN ALL CASES, HOWEVER, PUR-CHASE INTENTIONS ARE STRONGLY EXPLAINED BY CONSUMERS' OVERALL ATTITUDES TOWARDS GENETIC MODIFICATION IN FOOD PRODUCTION....

Genetic effects of ionizing radiation and repair processes

International Nuclear Information System (INIS)

Tuschl, H.

1986-11-01

Since DNA (=desoxyribonucleic acid) is the largest molecule within the cell it is the most important target for direct and indirect radiation effects. Within DNA the total genetic information is stored, thus damage to DNA in germ cells causes genetic disorders and damage in somatic cells is implicated in cancer and immunodeficiences. Alterations of DNA structure are not only due to ionizing radiation effects, but also to spontaneous DNA modifications and damage from interactions with environmental ultraviolet light and chemical agents. To maintain its genetic integrity, each organism had to develop different repair systems able to recognize and remove DNA damage. Repeated exposure to a DNA damaging agent can even lead to adaptation processes and increased resistance to the same agent. At normal function of repair systems it can be assumed that the capacity of those systems is adequate to scope with the effects of low radiation doses. (Author)

Novel base-pairing interactions at the tRNA wobble position crucial for accurate reading of the genetic code

Science.gov (United States)

Rozov, Alexey; Demeshkina, Natalia; Khusainov, Iskander; Westhof, Eric; Yusupov, Marat; Yusupova, Gulnara

2016-01-01

Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNALysUUU with hypermodified 5-methylaminomethyl-2-thiouridine (mnm5s2U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine-pyrimidine mismatches. We show that mnm5s2U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism.

DNA Mapping Made Simple: An Intellectual Activity about the Genetic Modification of Organisms

Science.gov (United States)

Marques, Miguel; Arrabaca, Joao; Chagas, Isabel

2004-01-01

Since the discovery of the DNA double helix (in 1953 by Watson and Crick), technologies have been developed that allow scientists to manipulate the genome of bacteria to produce human hormones, as well as the genome of crop plants to achieve high yield and enhanced flavor. The universality of the genetic code has allowed DNA isolated from a…

CRISPR-Cas and Restriction-Modification Act Additively against Conjugative Antibiotic Resistance Plasmid Transfer in Enterococcus faecalis

OpenAIRE

Price, Valerie J.; Huo, Wenwen; Sharifi, Ardalan; Palmer, Kelli L.

2016-01-01

ABSTRACT Enterococcus faecalis is an opportunistic pathogen and a leading cause of nosocomial infections. Conjugative pheromone-responsive plasmids are narrow-host-range mobile genetic elements (MGEs) that are rapid disseminators of antibiotic resistance in the faecalis species. Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification confer acquired and innate immunity, respectively, against MGE acquisition in bacteria. Most multidrug-resistant E.?fa...

A new physical mapping approach refines the sex-determining gene positions on the Silene latifolia Y-chromosome

Science.gov (United States)

Kazama, Yusuke; Ishii, Kotaro; Aonuma, Wataru; Ikeda, Tokihiro; Kawamoto, Hiroki; Koizumi, Ayako; Filatov, Dmitry A.; Chibalina, Margarita; Bergero, Roberta; Charlesworth, Deborah; Abe, Tomoko; Kawano, Shigeyuki

2016-01-01

Sex chromosomes are particularly interesting regions of the genome for both molecular genetics and evolutionary studies; yet, for most species, we lack basic information, such as the gene order along the chromosome. Because they lack recombination, Y-linked genes cannot be mapped genetically, leaving physical mapping as the only option for establishing the extent of synteny and homology with the X chromosome. Here, we developed a novel and general method for deletion mapping of non-recombining regions by solving “the travelling salesman problem”, and evaluate its accuracy using simulated datasets. Unlike the existing radiation hybrid approach, this method allows us to combine deletion mutants from different experiments and sources. We applied our method to a set of newly generated deletion mutants in the dioecious plant Silene latifolia and refined the locations of the sex-determining loci on its Y chromosome map.

Most Colorful Example of Genetic Assimilation? Exploring the Evolutionary Destiny of Recurrent Phenotypic Accommodation.

Science.gov (United States)

Badyaev, Alexander V; Potticary, Ahva L; Morrison, Erin S

2017-08-01

Evolution of adaptation requires both generation of novel phenotypic variation and retention of a locally beneficial subset of this variation. Such retention can be facilitated by genetic assimilation, the accumulation of genetic and molecular mechanisms that stabilize induced phenotypes and assume progressively greater control over their reliable production. A particularly strong inference into genetic assimilation as an evolutionary process requires a system where it is possible to directly evaluate the extent to which an induced phenotype is progressively incorporated into preexisting developmental pathways. Evolution of diet-dependent pigmentation in birds-where external carotenoids are coopted into internal metabolism to a variable degree before being integrated with a feather's developmental processes-provides such an opportunity. Here we combine a metabolic network view of carotenoid evolution with detailed empirical study of feather modifications to show that the effect of physical properties of carotenoids on feather structure depends on their metabolic modification, their environmental recurrence, and biochemical redundancy, as predicted by the genetic assimilation hypothesis. Metabolized carotenoids caused less stochastic variation in feather structure and were more closely integrated with feather growth than were dietary carotenoids of the same molecular weight. These patterns were driven by the recurrence of organism-carotenoid associations: commonly used dietary carotenoids and biochemically redundant derived carotenoids caused less stochastic variation in feather structure than did rarely used or biochemically unique compounds. We discuss implications of genetic assimilation processes for the evolutionary diversification of diet-dependent animal coloration.

Ultrastructural demonstration of chemical modification of melanogenesis in hairless mouse skin

International Nuclear Information System (INIS)

Nishimura, M.; Gellin, G.A.; Hoshino, S.; Epstein, J.H.; Epstein, W.L.; Fukuyama, K.

1982-01-01

We investigated chemical and physical modifications of the genetically determined ultrastructure of melanosomes. The flank skin of hairless mice was treated with ultraviolet energy (UV) shorter than 320 nm or with a combination of a photosensitizer and UV (PUVA treatment). All melanosomes in the induced melanocytes and those in resident melanocytes in the ear skin showed eumelanogenesis, although the degree of melanin deposition differed considerably according to the induction process. Eumelanogenesis was most advanced in the resident melanocytes while PUVA-induced melanocytes showed more immature premelanosomes. We then topically applied 4-tertiary butyl catechol on the skin. The depigmenting agent caused an appearance of pheomelanosomes. The alteration in melanogenesis was seen most distinctly in premelanosomes of the PUVA-induced cells. Altered ultrastructure was also observed in matured melanosomes; this change was most apparent in the resident melanocytes. These findings indicate that cells with eumelanogenesis may undergo pheomelanogenesis. The present study demonstrated effects of chemicals on genetically determined function of melanocytes by quantitative analysis of melanosome ultrastructure

Modifications to POISSON

International Nuclear Information System (INIS)

Harwood, L.H.

1981-01-01

At MSU we have used the POISSON family of programs extensively for magnetic field calculations. In the presently super-saturated computer situation, reducing the run time for the program is imperative. Thus, a series of modifications have been made to POISSON to speed up convergence. Two of the modifications aim at having the first guess solution as close as possible to the final solution. The other two aim at increasing the convergence rate. In this discussion, a working knowledge of POISSON is assumed. The amount of new code and expected time saving for each modification is discussed

Genetic Testing for Type 2 Diabetes in High-Risk Children: the Case for Primordial Prevention

Directory of Open Access Journals (Sweden)

Jennifer Wessel

2017-09-01

Full Text Available Extensive research now demonstrates that lifestyle modification can significantly lower risk of developing type 2 diabetes (T2D in high-risk adults. In children, the evidence for lifestyle modification is not as robust, but the rapidly rising rate of obesity in children coupled with the substantial difficulty in changing behaviors later in life illuminates the need to implement prevention efforts early in the life course of children. Genetic data can now be used early in the life course to identify children at high-risk of developing T2D before traditional clinical measures can detect the presence of prediabetes; a metabolic condition associated with obesity that significantly increases risk for developing T2D.  Such early detection of risk may enable the promotion of “primordial prevention” in which parents implement behavior change for their at risk children.  Young children with genetic risk are a novel target population.  Here we review the literature on genetic testing for prevention as it relates to chronic diseases and specifically use T2D as a model. We discuss the history of primordial prevention, the need for primordial prevention of T2D and the role genetic testing has in primordial prevention of high-risk families.

Genetic modification of risk assessment based on staging of preclinical type 1 diabetes in siblings of affected children.

Science.gov (United States)

Mrena, S; Savola, K; Kulmala, P; Reijonen, H; Ilonen, J; Akerblom, H K; Knip, M

2003-06-01

We set out to study the association between human leukocyte antigen-defined genetic disease susceptibility and the stage of preclinical type 1 diabetes and whether genetic predisposition affects the natural course of preclinical diabetes in initially nondiabetic siblings of affected children. A total of 701 initially unaffected siblings were graded into four stages of preclinical type 1 diabetes based on the initial number of disease-associated autoantibodies detectable close to the time of diagnosis of the index case: no prediabetes (no antibodies), early (one antibody specificity), advanced (two antibodies), and late prediabetes (three or more antibodies). Another classification system covering 659 siblings was based on a combination of the initial number of antibodies and the first-phase insulin response (FPIR) to iv glucose: no prediabetes (no antibodies), early (one antibody specificity, normal FPIR), advanced (two or more antibodies, normal FPIR), and late prediabetes (at least one antibody, reduced FPIR). Genetic susceptibility to type 1 diabetes was defined by human leukocyte antigen identity and DR and DQ genotypes. There was a higher proportion of siblings with late prediabetes initially among those with strong genetic disease susceptibility than among those with decreased genetic predisposition (16.7% vs. 0.5%; P siblings with no signs of prediabetes among those with genotypes conferring decreased risk (91.2% vs. 70.4% among those with high-risk DQB1 genotypes; P siblings than when combined with genetic susceptibility. Genetic susceptibility played a role in whether the initial prediabetic stage progressed (progression in 29.6% of the high-risk siblings compared with 6.6% of the siblings with DQB1 genotypes conferring decreased risk; P siblings of affected children.

Evaluation of Gene Modification Strategies for the Development of Low-Alcohol-Wine Yeasts

Science.gov (United States)

Kutyna, D. R.; Solomon, M. R.; Black, C. A.; Borneman, A.; Henschke, P. A.; Pretorius, I. S.; Chambers, P. J.

2012-01-01

Saccharomyces cerevisiae has evolved a highly efficient strategy for energy generation which maximizes ATP energy production from sugar. This adaptation enables efficient energy generation under anaerobic conditions and limits competition from other microorganisms by producing toxic metabolites, such as ethanol and CO2. Yeast fermentative and flavor capacity forms the biotechnological basis of a wide range of alcohol-containing beverages. Largely as a result of consumer demand for improved flavor, the alcohol content of some beverages like wine has increased. However, a global trend has recently emerged toward lowering the ethanol content of alcoholic beverages. One option for decreasing ethanol concentration is to use yeast strains able to divert some carbon away from ethanol production. In the case of wine, we have generated and evaluated a large number of gene modifications that were predicted, or known, to impact ethanol formation. Using the same yeast genetic background, 41 modifications were assessed. Enhancing glycerol production by increasing expression of the glyceraldehyde-3-phosphate dehydrogenase gene, GPD1, was the most efficient strategy to lower ethanol concentration. However, additional modifications were needed to avoid negatively affecting wine quality. Two strains carrying several stable, chromosomally integrated modifications showed significantly lower ethanol production in fermenting grape juice. Strain AWRI2531 was able to decrease ethanol concentrations from 15.6% (vol/vol) to 13.2% (vol/vol), whereas AWRI2532 lowered ethanol content from 15.6% (vol/vol) to 12% (vol/vol) in both Chardonnay and Cabernet Sauvignon juices. Both strains, however, produced high concentrations of acetaldehyde and acetoin, which negatively affect wine flavor. Further modifications of these strains allowed reduction of these metabolites. PMID:22729542

Ultrasensitive Direct Quantification of Nucleobase Modifications in DNA by Surface-Enhanced Raman Scattering: The Case of Cytosine.

Science.gov (United States)

Morla-Folch, Judit; Xie, Hai-nan; Gisbert-Quilis, Patricia; Gómez-de Pedro, Sara; Pazos-Perez, Nicolas; Alvarez-Puebla, Ramon A; Guerrini, Luca

2015-11-09

Recognition of chemical modifications in canonical nucleobases of nucleic acids is of key importance since such modified variants act as different genetic encoders, introducing variability in the biological information contained in DNA. Herein, we demonstrate the feasibility of direct SERS in combination with chemometrics and microfluidics for the identification and relative quantification of 4 different cytosine modifications in both single- and double-stranded DNA. The minute amount of DNA required per measurement, in the sub-nanogram regime, removes the necessity of pre-amplification or enrichment steps (which are also potential sources of artificial DNA damages). These findings show great potentials for the development of fast, low-cost and high-throughput screening analytical devices capable of detecting known and unknown modifications in nucleic acids (DNA and RNA) opening new windows of activity in several fields such as biology, medicine and forensic sciences. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Defective APETALA2 Genes Lead to Sepal Modification in Brassica Crops

Science.gov (United States)

Zhang, Yanfeng; Huang, Shuhua; Wang, Xuefang; Liu, Jianwei; Guo, Xupeng; Mu, Jianxin; Tian, Jianhua; Wang, Xiaofeng

2018-01-01

Many vegetable and oilseed crops belong to Brassica species. The seed production of these crops is hampered often by abnormal floral organs, especially under the conditions of abiotic conditions. However, the molecular reasons for these abnormal floral organs remains poorly understood. Here, we report a novel pistil-like flower mutant of B. rapa. In the flower of this mutant, the four sepals are modified to one merged carpel that look like a ring in the sepal positions, enveloping some abnormal stamens and a pistil, and resulting in poor seed production. This novel mutant is named sepal-carpel modification (scm). DNA sequencing showed that the BrAP2a gene, the ortholog of Arabidopsis APETALA2 (AP2) that specifies sepal identity, losses the function of in scm mutant due to a 119-bp repeated sequence insertion that resulted in an early transcription termination. BrAP2b, the paralog of BrAP2a featured two single-nucleotide substitutions that cause a single amino acid substitution in the highly conserved acidic serine-rich transcriptional activation domain. Each of the two BrAP2 genes rescues the sepal defective phenotype of the ap2-5 mutant of Arabidopsis. Furthermore, the knockout mutation of the corresponding BnAP2 genes of oilseed rape (B. napus) by CRISPR/Cas9-mediated genome editing system resulted in scm-like phenotype. These results suggest that BrAP2 gene plays a key role in sepal modification. Our finding provides an insight into molecular mechanism underlying morphological modification of floral organs and is useful for genetic manipulation of flower modification and improvement of seed production of Brassica crops. PMID:29616073

Defective APETALA2 Genes Lead to Sepal Modification in Brassica Crops

Directory of Open Access Journals (Sweden)

Yanfeng Zhang

2018-03-01

Full Text Available Many vegetable and oilseed crops belong to Brassica species. The seed production of these crops is hampered often by abnormal floral organs, especially under the conditions of abiotic conditions. However, the molecular reasons for these abnormal floral organs remains poorly understood. Here, we report a novel pistil-like flower mutant of B. rapa. In the flower of this mutant, the four sepals are modified to one merged carpel that look like a ring in the sepal positions, enveloping some abnormal stamens and a pistil, and resulting in poor seed production. This novel mutant is named sepal-carpel modification (scm. DNA sequencing showed that the BrAP2a gene, the ortholog of Arabidopsis APETALA2 (AP2 that specifies sepal identity, losses the function of in scm mutant due to a 119-bp repeated sequence insertion that resulted in an early transcription termination. BrAP2b, the paralog of BrAP2a featured two single-nucleotide substitutions that cause a single amino acid substitution in the highly conserved acidic serine-rich transcriptional activation domain. Each of the two BrAP2 genes rescues the sepal defective phenotype of the ap2-5 mutant of Arabidopsis. Furthermore, the knockout mutation of the corresponding BnAP2 genes of oilseed rape (B. napus by CRISPR/Cas9-mediated genome editing system resulted in scm-like phenotype. These results suggest that BrAP2 gene plays a key role in sepal modification. Our finding provides an insight into molecular mechanism underlying morphological modification of floral organs and is useful for genetic manipulation of flower modification and improvement of seed production of Brassica crops.

Detecting genetic introgression: high levels of intersubspecific recombination found in Xylella fastidiosa in Brazil.

Science.gov (United States)

Nunney, Leonard; Yuan, Xiaoli; Bromley, Robin E; Stouthamer, Richard

2012-07-01

Documenting the role of novel mutation versus homologous recombination in bacterial evolution, and especially in the invasion of new hosts, is central to understanding the long-term dynamics of pathogenic bacteria. We used multilocus sequence typing (MLST) to study this issue in Xylella fastidiosa subsp. pauca from Brazil, a bacterium causing citrus variegated chlorosis (CVC) and coffee leaf scorch (CLS). All 55 citrus isolates typed (plus one coffee isolate) defined three similar sequence types (STs) dominated by ST11 (85%), while the remaining 22 coffee isolates defined two STs, mainly ST16 (74%). This low level of variation masked unusually large allelic differences (>1% divergence with no intermediates) at five loci (leuA, petC, malF, cysG, and holC). We developed an introgression test to detect whether these large differences were due to introgression via homologous recombination from another X. fastidiosa subspecies. Using additional sequencing around these loci, we established that the seven randomly chosen MLST targets contained seven regions of introgression totaling 2,172 bp of 4,161 bp (52%), only 409 bp (10%) of which were detected by other recombination tests. This high level of introgression suggests the hypothesis that X. fastidiosa subsp. pauca became pathogenic on citrus and coffee (crops cultivated in Brazil for several hundred years) only recently after it gained genetic variation via intersubspecific recombination, facilitating a switch from native hosts. A candidate donor is the subspecies infecting plum in the region since 1935 (possibly X. fastidiosa subsp. multiplex). This hypothesis predicts that nonrecombinant native X. fastidiosa subsp. pauca (not yet isolated) does not cause disease in citrus or coffee.

Unassigned Codons, Nonsense Suppression, and Anticodon Modifications in the Evolution of the Genetic Code

NARCIS (Netherlands)

P.T.S. van der Gulik (Peter); W.D. Hoff (Wouter)

2011-01-01

htmlabstractThe origin of the genetic code is a central open problem regarding the early evolution of life. Here, we consider two undeveloped but important aspects of possible scenarios for the evolutionary pathway of the translation machinery: the role of unassigned codons in early stages

Chemical Genetics — A Versatile Method to Combine Science and Higher Level Teaching in Molecular Genetics

Directory of Open Access Journals (Sweden)

Björn Sandrock

2012-10-01

Full Text Available Phosphorylation is a key event in many cellular processes like cell cycle, transformation of environmental signals to transcriptional activation or polar growth. The chemical genetics approach can be used to analyse the effect of highly specific inhibition in vivo and is a promising method to screen for kinase targets. We have used this approach to study the role of the germinal centre kinase Don3 during the cell division in the phytopathogenic fungus Ustilago maydis. Due to the easy determination of the don3 phenotype we have chosen this approach for a genetic course for M.Sc. students and for IMPRS (International Max-Planck research school students. According to the principle of “problem-based learning” the aim of this two-week course is to transfer knowledge about the broad spectrum of kinases to the students and that the students acquire the ability to design their own analog-sensitive kinase of interest. In addition to these training goals, we benefit from these annual courses the synthesis of basic constructs for genetic modification of several kinases in our model system U. maydis.

Profiling bacterial kinase activity using a genetic circuit

DEFF Research Database (Denmark)

van der Helm, Eric; Bech, Rasmus; Lehning, Christina Eva

Phosphorylation is a post-translational modification that regulates the activity of several key proteins in bacteria and eukaryotes. Accordingly, a variety of tools has been developed to measure kinase activity. To couple phosphorylation to an in vivo fluorescent readout we used the Bacillus...... subtilis kinase PtkA, transmembrane activator TkmA and the repressor FatR to construct a genetic circuit in E. coli. By tuning the repressor and kinase expression level at the same time, we were able to show a 4.2-fold increase in signal upon kinase induction. We furthermore validated that the previously...... reported FatR Y45E mutation1 attenuates operator repression. This genetic circuit provides a starting point for computational protein design and a metagenomic library-screening tool....

Genetic Variations Involved in Vitamin E Status

Directory of Open Access Journals (Sweden)

Patrick Borel

2016-12-01

Full Text Available Vitamin E (VE is the generic term for four tocopherols and four tocotrienols that exhibit the biological activity of α-tocopherol. VE status, which is usually estimated by measuring fasting blood VE concentration, is affected by numerous factors, such as dietary VE intake, VE absorption efficiency, and VE catabolism. Several of these factors are in turn modulated by genetic variations in genes encoding proteins involved in these factors. To identify these genetic variations, two strategies have been used: genome-wide association studies and candidate gene association studies. Each of these strategies has its advantages and its drawbacks, nevertheless they have allowed us to identify a list of single nucleotide polymorphisms associated with fasting blood VE concentration and α-tocopherol bioavailability. However, much work remains to be done to identify, and to replicate in different populations, all the single nucleotide polymorphisms involved, to assess the possible involvement of other kind of genetic variations, e.g., copy number variants and epigenetic modifications, in order to establish a reliable list of genetic variations that will allow us to predict the VE status of an individual by knowing their genotype in these genetic variations. Yet, the potential usefulness of this area of research is exciting with regard to personalized nutrition and for future clinical trials dedicated to assessing the biological effects of the various isoforms of VE.

Modification of COMT-dependent pain sensitivity by psychological stress and sex.

Science.gov (United States)

Meloto, Carolina B; Bortsov, Andrey V; Bair, Eric; Helgeson, Erika; Ostrom, Cara; Smith, Shad B; Dubner, Ronald; Slade, Gary D; Fillingim, Roger B; Greenspan, Joel D; Ohrbach, Richard; Maixner, William; McLean, Samuel A; Diatchenko, Luda

2016-04-01

Catecholamine-O-methyltransferase (COMT) is a polymorphic gene whose variants affect enzymatic activity and pain sensitivity via adrenergic pathways. Although COMT represents one of the most studied genes in human pain genetics, findings regarding its association with pain phenotypes are not always replicated. Here, we investigated if interactions among functional COMT haplotypes, stress, and sex can modify the effect of COMT genetic variants on pain sensitivity. We tested these interactions in a cross-sectional study, including 2 cohorts, one of 2972 subjects tested for thermal pain sensitivity (Orofacial Pain: Prospective Evaluation and Risk Assessment) and one of 948 subjects with clinical acute pain after motor vehicle collision (post-motor vehicle collision). In both cohorts, the COMT high-pain sensitivity (HPS) haplotype showed robust interaction with stress and number of copies of the HPS haplotype was positively associated with pain sensitivity in nonstressed individuals, but not in stressed individuals. In the post-motor vehicle collision cohort, there was additional modification by sex: the HPS-stress interaction was apparent in males, but not in females. In summary, our findings indicate that stress and sex should be evaluated in association studies aiming to investigate the effect of COMT genetic variants on pain sensitivity.

Radiation-induced-radioresistance: mechanisms and modification radioprotection

International Nuclear Information System (INIS)

Bala, Madhu

2005-01-01

Full text: The term radiation-induced-radioresistance (RIR) has been chosen to explain a particular class of resistance against lethal doses of radiation, which is transient and is induced by pre-exposure to low doses of radiation. This is a genetically governed phenomenon and is different from adaptation which in one of its several senses, refers to evolutionary transformation into new behavioural patterns. RIR is understood to be an evolutionarily conserved fundamental cellular defense mechanism. Small doses of radiation acting as stress stimuli evoke a concerted action of molecular pathways which help the organism to cope-up with the genotoxic effects of lethal doses of radiation given subsequently. Such molecular pathways are a complex interplay of genetic and biochemical entities and are increasingly becoming the focus of research world over. Most of our information on this subject has been gathered from prokaryotes, simpler eukaryotes, human cells and the epidemiological studies. A number of genes such as GADD 45, CDKN1A, PBP74, DIR1, DDR have been reported by to participate in RIR. However, till date, the mechanism of RIR remain poorly understood. In this deliberation some of our findings on mechanisms of RIR will be presented. Further, modification of RIR by a metabolic modifier, presently under clinical investigations for tumor radiotherapy, will also be presented

Nuclear lactate dehydrogenase modulates histone modification in human hepatocytes

Energy Technology Data Exchange (ETDEWEB)

Castonguay, Zachary; Auger, Christopher; Thomas, Sean C.; Chahma, M’hamed; Appanna, Vasu D., E-mail: vappanna@laurentian.ca

2014-11-07

Highlights: • Nuclear LDH is up-regulated under oxidative stress. • SIRT1 is co-immunoprecipitated bound to nuclear LDH. • Nuclear LDH is involved in histone deacetylation and epigenetics. - Abstract: It is becoming increasingly apparent that the nucleus harbors metabolic enzymes that affect genetic transforming events. Here, we describe a nuclear isoform of lactate dehydrogenase (nLDH) and its ability to orchestrate histone deacetylation by controlling the availability of nicotinamide adenine dinucleotide (NAD{sup +}), a key ingredient of the sirtuin-1 (SIRT1) deacetylase system. There was an increase in the expression of nLDH concomitant with the presence of hydrogen peroxide (H{sub 2}O{sub 2}) in the culture medium. Under oxidative stress, the NAD{sup +} generated by nLDH resulted in the enhanced deacetylation of histones compared to the control hepatocytes despite no discernable change in the levels of SIRT1. There appeared to be an intimate association between nLDH and SIRT1 as these two enzymes co-immunoprecipitated. The ability of nLDH to regulate epigenetic modifications by manipulating NAD{sup +} reveals an intricate link between metabolism and the processing of genetic information.

Readiness of adolescents to use genetically modified organisms according to their knowledge and emotional attitude towards GMOs.

Science.gov (United States)

Lachowski, Stanisław; Jurkiewicz, Anna; Choina, Piotr; Florek-Łuszczki, Magdalena; Buczaj, Agnieszka; Goździewska, Małgorzata

2017-06-07

Agriculture based on genetically modified organisms plays an increasingly important role in feeding the world population, which is evidenced by a considerable growth in the size of land under genetically modified crops (GM). Uncertainty and controversy around GM products are mainly due to the lack of accurate and reliable information, and lack of knowledge concerning the essence of genetic modifications, and the effect of GM food on the human organism, and consequently, a negative emotional attitude towards what is unknown. The objective of the presented study was to discover to what extent knowledge and the emotional attitude of adolescents towards genetically modified organisms is related with acceptance of growing genetically modified plants or breeding GM animals on own farm or allotment garden, and the purchase and consumption of GM food, as well as the use of GMOs in medicine. The study was conducted by the method of a diagnostic survey using a questionnaire designed by the author, which covered a group of 500 adolescents completing secondary school on the level of maturity examination. The collected material was subjected to statistical analysis. Research hypotheses were verified using chi-square test (χ 2 ), t-Student test, and stepwise regression analysis. Stepwise regression analysis showed that the readiness of adolescents to use genetically modified organisms as food or for the production of pharmaceuticals, the production of GM plants or animals on own farm, depends on an emotional-evaluative attitude towards GMOs, and the level of knowledge concerning the essence of genetic modifications.

Invited review: Breeding and ethical perspectives on genetically modified and genome edited cattle.

Science.gov (United States)

Eriksson, S; Jonas, E; Rydhmer, L; Röcklinsberg, H

2018-01-01

The hot topic of genetic modification and genome editing is sometimes presented as a rapid solution to various problems in the field of animal breeding and genetics. These technologies hold potential for future use in agriculture but we need to be aware of difficulties in large-scale application and integration in breeding schemes. In this review, we discuss applications of both classical genetic modifications (GM) using vectors and genome editing in dairy cattle breeding. We use an interdisciplinary approach considering both ethical and animal breeding perspectives. Decisions on how to make use of these techniques need to be made based not only on what is possible, but on what is reasonable to do. Principles of animal integrity, naturalness, risk perception, and animal welfare issues are examples of ethically relevant factors to consider. These factors also influence public perception and decisions about regulations by authorities. We need to acknowledge that we lack complete understanding of the genetic background of complex traits. It may be difficult, therefore, to predict the full effect of certain modifications in large-scale breeding programs. We present 2 potential applications: genome editing to dispense with dehorning, and insertion of human genes in bovine genomes to improve udder health as an example of classical GM. Both of these cases could be seen as beneficial for animal welfare but they differ in other aspects. In the former case, a genetic variant already present within the species is introduced, whereas in the latter case, transgenic animals are generated-this difference may influence how society regards the applications. We underline that the use of GM, as well as genome editing, of farm animals such as cattle is not independent of the context, and should be considered as part of an entire process, including, for example, the assisted reproduction technology that needs to be used. We propose that breeding organizations and breeding companies

GENETIC MODIFICATION OF GIBBERELLIC ACID SIGNALING TO PROMOTE CARBON SEQUESTRATION IN TREE ROOTS AND STEMS

Energy Technology Data Exchange (ETDEWEB)

Busov, Victor

2013-03-05

encode proteins involved in gibberellin metabolism or signalling. Intact genomic copies of PtGA20ox7, PtGA2ox2,Pt RGL1_1, PtRGL1_2 and PtGAI1 genes from the genome-sequenced Populus trichocarpa clone Nisqually-1 were transformed into Populus tremula - alba (clone INRA 717-1B4), and growth, morphology and xylem cell size characterized in the greenhouse. Each cisgene encompassed 1-2?kb of 5' and 1?kb of 3' flanking DNA, as well as all native exons and introns. Large numbers of independent insertion events per cisgene (19-38), including empty vector controls, were studied. Three of the cisgenic modifications had significant effects on plant growth rate, morphology or wood properties. The PtGA20ox7 cisgene increased rate of shoot regeneration in vitro, accelerated early growth, and variation in growth rate was correlated with PtGA20ox7 gene expression. PtRGL1_1 and PtGA2ox2 caused reduced growth, while PtRGL1_2 gave rise to plants that grew normally but had significantly longer xylem fibres. RT-PCR studies suggested that the lack of growth inhibition observed in PtRGL1_2 cisgenic plants was a result of co-suppression. PtGAI1 slowed regeneration rate and both PtGAI1 and PtGA20ox7 gave rise to increased variance among events for early diameter and volume index, respectively. Our work suggests that cisgenic insertion of additional copies of native genes involved in growth regulation may provide tools to help modify plant architecture, expand the genetic variance in plant architecture available to breeders and accelerate transfer of alleles between difficult-to-cross species. The role of gibberellins (GAs) in regulation of lateral root development is poorly understood. We show that GA-deficient (35S:PcGA2ox1) and GA-insensitive (35S:rgl1) transgenic Populus exhibited increased lateral root proliferation and elongation under in vitro and greenhouse conditions, and these effects were reversed by exogenous GA treatment. In addition, RNA interference suppression of two

Accommodating for plant modifications

International Nuclear Information System (INIS)

Weirich, P.H.

1977-01-01

Modification to a nuclear power plant may have different causes: 1) new instructions by the authorities; 2) changes of the marginal conditions on the construction site; 3) progress in the technological development. - Examples from different plants are supposed to demonstrate how such changes influence the planning or the construction and how they are integrated in the process of preparation. A distinction can be made between modifications before the completion of the submission of the order, during the phase of preparatory planning and during the construction phase. Of great importance are especially modifications made after the beginning of the construction works, since, in general, there is little scope for technical modifications and since consequences for the time schedule are to be expected. (orig.) [de

Investigating Novice and Expert Conceptions of Genetically Modified Organisms.

Science.gov (United States)

Potter, Lisa M; Bissonnette, Sarah A; Knight, Jonathan D; Tanner, Kimberly D

2017-01-01

The aspiration of biology education is to give students tools to apply knowledge learned in the classroom to everyday life. Genetic modification is a real-world biological concept that relies on an in-depth understanding of the molecular behavior of DNA and proteins. This study investigated undergraduate biology students' conceptions of genetically modified organisms (GMOs) when probed with real-world, molecular and cellular, and essentialist cues, and how those conceptions compared across biology expertise. We developed a novel written assessment tool and administered it to 120 non-biology majors, 154 entering biology majors, 120 advanced biology majors (ABM), and nine biology faculty. Results indicated that undergraduate biology majors rarely included molecular and cellular rationales in their initial explanations of GMOs. Despite ABM demonstrating that they have much of the biology knowledge necessary to understand genetic modification, they did not appear to apply this knowledge to explaining GMOs. Further, this study showed that all undergraduate student populations exhibited evidence of essentialist thinking while explaining GMOs, regardless of their level of biology training. Finally, our results suggest an association between scientifically accurate ideas and the application of molecular and cellular rationales, as well as an association between misconceptions and essentialist rationales. © 2017 L. M. Potter et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Mammalian small nucleolar RNAs are mobile genetic elements.

Directory of Open Access Journals (Sweden)

Michel J Weber

2006-12-01

Full Text Available Small nucleolar RNAs (snoRNAs of the H/ACA box and C/D box categories guide the pseudouridylation and the 2'-O-ribose methylation of ribosomal RNAs by forming short duplexes with their target. Similarly, small Cajal body-specific RNAs (scaRNAs guide modifications of spliceosomal RNAs. The vast majority of vertebrate sno/scaRNAs are located in introns of genes transcribed by RNA polymerase II and processed by exonucleolytic trimming after splicing. A bioinformatic search for orthologues of human sno/scaRNAs in sequenced mammalian genomes reveals the presence of species- or lineage-specific sno/scaRNA retroposons (sno/scaRTs characterized by an A-rich tail and an approximately 14-bp target site duplication that corresponds to their insertion site, as determined by interspecific genomic alignments. Three classes of snoRTs are defined based on the extent of intron and exon sequences from the snoRNA parental host gene they contain. SnoRTs frequently insert in gene introns in the sense orientation at genomic hot spots shared with other genetic mobile elements. Previously characterized human snoRNAs are encoded in retroposons whose parental copies can be identified by phylogenic analysis, showing that snoRTs can be faithfully processed. These results identify snoRNAs as a new family of mobile genetic elements. The insertion of new snoRNA copies might constitute a safeguard mechanism by which the biological activity of snoRNAs is maintained in spite of the risk of mutations in the parental copy. I furthermore propose that retroposition followed by genetic drift is a mechanism that increased snoRNA diversity during vertebrate evolution to eventually acquire new RNA-modification functions.

Biomaterials modification by ion beam

International Nuclear Information System (INIS)

Zhang Tonghe; Yi Zhongzhen; Zhang Xu; Wu Yuguang

2001-01-01

Ion beam technology is one of best ways for the modification of biomaterials. The results of ion beam modification of biomaterials are given. The method and results of improved biocompatibility are indicated by ion beam technology. The future development of ion beam modification of biomaterials is discussed

Assessment of genetic results of ionizing radiation effect on hydrobionts population

International Nuclear Information System (INIS)

Pechkurenkov, V.L.; Pokrovskaya, L.G.; Fetisov, A.N.

1987-01-01

The effect of dose value and rate on genetic results of chronic radiation with the low dose rate is estimated. At such irradiation the yield of abberant anaphases of embryos is determined by the dose value and it does not depend on the dose rate. The threshold radiation dose rate of the developing fish roe equals 2-3 cGy/h when ignoring the medium modifying factors. The estimation of possible limits of modification of genetic effects of radiation with the low rate when changing environmental factors is given. The model allowing to forecast the appearance of genetic effects of radiation with the low dose rate is constructed. The correspondence between the data obtained in laboratory experiments using organisms living in water reservoirs contaminated experimentally by radionuclides is marked

Safety of modifications at nuclear power plants - the role of minor modifications and human and organisational factors

International Nuclear Information System (INIS)

2005-01-01

Operating experience repeatedly shows that changes and modifications at nuclear power plants (NPPs) may lead to safety significant events. At the same time, modifications are necessary to ensure a safe and economic functioning of the NPPs. To ensure safety in all plant configurations it is important that modification processes are given proper attention both by the utilities and the regulators. The operability, maintainability and testability of every modification should be thoroughly assessed from different points of view to ensure that no safety problems are introduced. The OECD/NEA Committee on Safety of Nuclear Installations (CSNI) has recently addressed the issue of modifications by organising a 'Workshop on Modifications at Nuclear Power Plants Operating Experience, Safety Significance and Role of Human Factors'. This workshop was undertaken as a joint effort of the Working Group on Operating Experience (WGOE) and the Special Experts Group on Human and Organisational Factors (SEGHOF), and it was held at the OECD Headquarters in Paris on October 6 to 8, 2003. The initiative to organise the workshop was taken by the WGOE and the SEGHOF based on findings from events and incidents due to modifications at nuclear power plants in the world and weaknesses experienced in modification processes. During the workshop, the WGOE focused on the theme of 'Minor Modifications and their Safety Significance', while the SEGHOF focused on the topic 'Human and Organisational Factors in NPP Modifications'. This report is based on material collected before the workshop, the workshop proceedings, discussions of the group of experts responsible for the arrangement of the workshop, and additional material collected by a consultant. The workshop was preceded by extensive preparations, which included collection of national surveys in response to questionnaires on modifications at the NPPs. Not all of these surveys were available at the workshop, but their findings have now been included

Modification of JRR-2

International Nuclear Information System (INIS)

Miyasaka, Yasuhiko

1978-01-01

This report gives an outline of some of the main modifications carried out around the Reactor Core on the Research Reactor JRR-2, at the Tokai Research Establishment of JAERI. The JRR-2 was shut down in December 1973, to improve it in heavy water leakage from the metal packing between core tank and support ring, corrosion of the lower shielding plug, and fault in the control-rod mechanism. Main modifications were a standing seal weld at the support ring to stop heavy water leakage, replacement of the reactor top shield and improvement of the helium system. The control-rod assemblies and the refueling devices were replaced by the newly designed ones also. In addition to the modification plan, the irradiated air exhaust system was improved to reduce radioactive argon gas release through the stack. Works were completed successfully in September 1975. But a light water leakage occurred at the stand pipe below the light water tank on November 11, 1975, which was repaired in about 4 months. When considering the operation of above 5,000 hours after the modification, however, the quality of the modification work may be said to be quite satisfactory. The present report in which works to the completion are described may be valuable as a record of reactor modification which is a new experience at JAERI. (auth.)

The perspectives for genetically modified cellulosic biofuels in the Central European conditions

Czech Academy of Sciences Publication Activity Database

Bláhová, P.; Janda, K.; Krištoufek, Ladislav

2014-01-01

Roč. 60, č. 6 (2014), s. 247-259 ISSN 0139-570X Grant - others:GA ČR(CZ) GAP402/11/0948 Program:GA Institutional support: RVO:67985556 Keywords : ellulosic biofuels * genetic modifications Subject RIV: AH - Economics Impact factor: 0.442, year: 2014 http://library.utia.cas.cz/separaty/2014/E/kristoufek-0433521.pdf

Recent advances on the posttranslational modifications of EXTs and their roles in plant cell walls

DEFF Research Database (Denmark)

Velasquez, Melina; Salter, Juan Salgado; Dorosz, Javier Gloazzo

2012-01-01

The genetic set up and the enzymes that define the O-glycosylation sites and transfer the activated sugars to cell wall glycoprotein Extensins (EXTs) have remained unknown for a long time. We are now beginning to see the emerging components of the molecular machinery that assembles these complex O......-glycoproteins on the plant cell wall. Genes conferring the posttranslational modifications, i.e., proline hydroxylation and subsequent O-glycosylation, of the EXTs have been recently identified. In this review we summarize the enzymes that define the O-glycosylation sites on the O-glycoproteins, i.e., the prolyl 4......-hydroxylases (P4Hs), the glycosyltransferases that transfer arabinose units (named arabinosyltransferases, AraTs), and the one responsible for transferring a single galactose (galactosyltransferase, GalT) on the protein EXT backbones. We discuss the effects of posttranslational modifications on the structure...

Genetic modulation of lipid profiles following lifestyle modification or metformin treatment: the Diabetes Prevention Program.

Directory of Open Access Journals (Sweden)

Toni I Pollin

Full Text Available Weight-loss interventions generally improve lipid profiles and reduce cardiovascular disease risk, but effects are variable and may depend on genetic factors. We performed a genetic association analysis of data from 2,993 participants in the Diabetes Prevention Program to test the hypotheses that a genetic risk score (GRS based on deleterious alleles at 32 lipid-associated single-nucleotide polymorphisms modifies the effects of lifestyle and/or metformin interventions on lipid levels and nuclear magnetic resonance (NMR lipoprotein subfraction size and number. Twenty-three loci previously associated with fasting LDL-C, HDL-C, or triglycerides replicated (P = 0.04-1 × 10(-17. Except for total HDL particles (r = -0.03, P = 0.26, all components of the lipid profile correlated with the GRS (partial |r| = 0.07-0.17, P = 5 × 10(-5-1 10(-19. The GRS was associated with higher baseline-adjusted 1-year LDL cholesterol levels (β = +0.87, SEE ± 0.22 mg/dl/allele, P = 8 × 10(-5, P(interaction = 0.02 in the lifestyle intervention group, but not in the placebo (β = +0.20, SEE ± 0.22 mg/dl/allele, P = 0.35 or metformin (β = -0.03, SEE ± 0.22 mg/dl/allele, P = 0.90; P(interaction = 0.64 groups. Similarly, a higher GRS predicted a greater number of baseline-adjusted small LDL particles at 1 year in the lifestyle intervention arm (β = +0.30, SEE ± 0.012 ln nmol/L/allele, P = 0.01, P(interaction = 0.01 but not in the placebo (β = -0.002, SEE ± 0.008 ln nmol/L/allele, P = 0.74 or metformin (β = +0.013, SEE ± 0.008 nmol/L/allele, P = 0.12; P(interaction = 0.24 groups. Our findings suggest that a high genetic burden confers an adverse lipid profile and predicts attenuated response in LDL-C levels and small LDL particle number to dietary and physical activity interventions aimed at weight loss.

Current issues connected with usage of genetically modified crops in production of feed and livestock feeding.

Science.gov (United States)

Kwiatek, K; Mazur, M; Sieradzki, Z

2008-01-01

Progress, which is brought by new advances in modern molecular biology, allowed interference in the genome of live organisms and gene manipulation. Introducing new genes to the recipient organism enables to give them new features, absent before. Continuous increase in the area of the biotech crops triggers continuous discussion about safety of genetically modified (GM) crops, including food and feed derived from them. Important issue connected with cultivation of genetically modified crops is a horizontal gene transfer and a bacterial antibiotic resistance. Discussion about safety of GM crops concerns also food allergies caused by eating genetically modified food. The problem of genetic modifications of GM crops used for livestock feeding is widely discussed, taking into account Polish feed law.

Permit application modifications

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

Permit application modifications

International Nuclear Information System (INIS)

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils

Trade-offs in the formation of consumer purchase intentions with regard to complex genetically modified products

DEFF Research Database (Denmark)

Bredahl, Lone; Søndergaard, Helle Alsted; Grunert, Klaus G.

2004-01-01

Consumers' product choices are increasingly influenced not only by the attributes of the products themselves, but also by characteristics of the way in which the product have been produced, including factors like origin, working conditions, and production technology. Genetic modification (GM...

Behavior Modification in Coaching.

Science.gov (United States)

Lynch, Annette Rutt; Stillman, Stephen M.

1979-01-01

An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors

Directory of Open Access Journals (Sweden)

Sylva Brabencová

2017-12-01

Full Text Available Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0 and Wassilewskija (Ws homogenized by two techniques (grinding in a cryomill or with a mortar and pestle. We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants. Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors.

Science.gov (United States)

Brabencová, Sylva; Ihnatová, Ivana; Potěšil, David; Fojtová, Miloslava; Fajkus, Jiří; Zdráhal, Zbyněk; Lochmanová, Gabriela

2017-01-01

Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation) among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0) and Wassilewskija (Ws) homogenized by two techniques (grinding in a cryomill or with a mortar and pestle). We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants). Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

Genetics of Schizophrenia: Historical Insights and Prevailing Evidence.

Science.gov (United States)

van de Leemput, J; Hess, J L; Glatt, S J; Tsuang, M T

2016-01-01

Schizophrenia's (SZ's) heritability and familial transmission have been known for several decades; however, despite the clear evidence for a genetic component, it has been very difficult to pinpoint specific causative genes. Even so genetic studies have taught us a lot, even in the pregenomic era, about the molecular underpinnings and disease-relevant pathways. Recurring themes emerged revealing the involvement of neurodevelopmental processes, glutamate regulation, and immune system differential activation in SZ etiology. The recent emergence of epigenetic studies aimed at shedding light on the biological mechanisms underlying SZ has provided another layer of information in the investigation of gene and environment interactions. However, this epigenetic insight also brings forth another layer of complexity to the (epi)genomic landscape such as interactions between genetic variants, epigenetic marks-including cross-talk between DNA methylation and histone modification processes-, gene expression regulation, and environmental influences. In this review, we seek to synthesize perspectives, including limitations and obstacles yet to overcome, from genetic and epigenetic literature on SZ through a qualitative review of risk factors and prevailing hypotheses. Encouraged by the findings of both genetic and epigenetic studies to date, as well as the continued development of new technologies to collect and interpret large-scale studies, we are left with a positive outlook for the future of elucidating the molecular genetic mechanisms underlying SZ and other complex neuropsychiatric disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

A reconfigurable NAND/NOR genetic logic gate.

Science.gov (United States)

Goñi-Moreno, Angel; Amos, Martyn

2012-09-18

Engineering genetic Boolean logic circuits is a major research theme of synthetic biology. By altering or introducing connections between genetic components, novel regulatory networks are built in order to mimic the behaviour of electronic devices such as logic gates. While electronics is a highly standardized science, genetic logic is still in its infancy, with few agreed standards. In this paper we focus on the interpretation of logical values in terms of molecular concentrations. We describe the results of computational investigations of a novel circuit that is able to trigger specific differential responses depending on the input standard used. The circuit can therefore be dynamically reconfigured (without modification) to serve as both a NAND/NOR logic gate. This multi-functional behaviour is achieved by a) varying the meanings of inputs, and b) using branch predictions (as in computer science) to display a constrained output. A thorough computational study is performed, which provides valuable insights for the future laboratory validation. The simulations focus on both single-cell and population behaviours. The latter give particular insights into the spatial behaviour of our engineered cells on a surface with a non-homogeneous distribution of inputs. We present a dynamically-reconfigurable NAND/NOR genetic logic circuit that can be switched between modes of operation via a simple shift in input signal concentration. The circuit addresses important issues in genetic logic that will have significance for more complex synthetic biology applications.

Genetic effects of combined chemical-X-ray treatments in male mouse germ cells

International Nuclear Information System (INIS)

Cattanach, B.M.; Rasberry, C.

1987-01-01

Several studies have shown that the yield of genetic damage induced by radiation in male mouse germ cells can be modified by chemical treatments. Pre-treatments with radio-protecting agents have given contradictory results but this appears to be largely attributable to the different germ cell stages tested and dependent upon the level of radiation damage induced. Pre-treatments which enhance the yield of genetic damage have been reported although, as yet, no tests have been conducted with radio-sensitizers. Another form of interaction between chemicals and radiation is specifically found with spermatogonial stem cells. Chemicals that kill cells can, by population depletion, substantially and predictably modify the genetic response to subsequent radiation exposure over a period of several days, or even weeks. Enhancement and reduction in the genetic yield can be attained, dependent upon the interval between treatments, with the modification also varying with the type of genetic damage scored. Post-treatment with one chemical (TEM) has been shown to reduce the genetic response to radiation exposure. (author)

Consumer preferences of genetically modified foods of vegetal and animal origin in Chile

Directory of Open Access Journals (Sweden)

Berta Schnettler

2012-03-01

Full Text Available Given the debate generated by Genetically Modified (GM foods in developed and developing countries, the aim was to evaluate the importance of determining factors in the preference of consumers in Temuco and Talca in central-southern Chile for GM foods using conjoint analysis and to determine the existence of different market segments using a survey of 800 people. Using conjoint analysis, it was established that, in general, genetic modification was a more important factor than either brand or price in the consumer's decision to purchase either food. Cluster analysis identified three segments: the largest (51.4% assigned greatest importance to brand and preferred genetically modified milk and tomato sauce; the second group (41.0% gave greatest importance to the existence of genetic manipulation and preferred non-genetically modified foods; the smallest segment (7.6% mainly valued price and preferred milk and tomato sauce with no genetic manipulation. The three segments rejected the store brand and preferred to pay less for both foods. The results are discussed based on studies conducted in developed and developing countries.

Genetic Modulation of Lipid Profiles following Lifestyle Modification or Metformin Treatment: The Diabetes Prevention Program

Science.gov (United States)

Jablonski, Kathleen A.; de Bakker, Paul I. W.; Taylor, Andrew; McAteer, Jarred; Pan, Qing; Horton, Edward S.; Delahanty, Linda M.; Altshuler, David; Shuldiner, Alan R.; Goldberg, Ronald B.; Florez, Jose C.; Bray, George A.; Culbert, Iris W.; Champagne, Catherine M.; Eberhardt, Barbara; Greenway, Frank; Guillory, Fonda G.; Herbert, April A.; Jeffirs, Michael L.; Kennedy, Betty M.; Lovejoy, Jennifer C.; Morris, Laura H.; Melancon, Lee E.; Ryan, Donna; Sanford, Deborah A.; Smith, Kenneth G.; Smith, Lisa L.; Amant, Julia A. St.; Tulley, Richard T.; Vicknair, Paula C.; Williamson, Donald; Zachwieja, Jeffery J.; Polonsky, Kenneth S.; Tobian, Janet; Ehrmann, David; Matulik, Margaret J.; Clark, Bart; Czech, Kirsten; DeSandre, Catherine; Hilbrich, Ruthanne; McNabb, Wylie; Semenske, Ann R.; Caro, Jose F.; Watson, Pamela G.; Goldstein, Barry J.; Smith, Kellie A.; Mendoza, Jewel; Liberoni, Renee; Pepe, Constance; Spandorfer, John; Donahue, Richard P.; Goldberg, Ronald B.; Prineas, Ronald; Rowe, Patricia; Calles, Jeanette; Cassanova-Romero, Paul; Florez, Hermes J.; Giannella, Anna; Kirby, Lascelles; Larreal, Carmen; McLymont, Valerie; Mendez, Jadell; Ojito, Juliet; Perry, Arlette; Saab, Patrice; Haffner, Steven M.; Montez, Maria G.; Lorenzo, Carlos; Martinez, Arlene; Hamman, Richard F.; Nash, Patricia V.; Testaverde, Lisa; Anderson, Denise R.; Ballonoff, Larry B.; Bouffard, Alexis; Calonge, B. Ned; Delve, Lynne; Farago, Martha; Hill, James O.; Hoyer, Shelley R.; Jortberg, Bonnie T.; Lenz, Dione; Miller, Marsha; Price, David W.; Regensteiner, Judith G.; Seagle, Helen; Smith, Carissa M.; Steinke, Sheila C.; VanDorsten, Brent; Horton, Edward S.; Lawton, Kathleen E.; Arky, Ronald A.; Bryant, Marybeth; Burke, Jacqueline P.; Caballero, Enrique; Callaphan, Karen M.; Ganda, Om P.; Franklin, Therese; Jackson, Sharon D.; Jacobsen, Alan M.; Jacobsen, Alan M.; Kula, Lyn M.; Kocal, Margaret; Malloy, Maureen A.; Nicosia, Maryanne; Oldmixon, Cathryn F.; Pan, Jocelyn; Quitingon, Marizel; Rubtchinsky, Stacy; Seely, Ellen W.; Schweizer, Dana; Simonson, Donald; Smith, Fannie; Solomon, Caren G.; Warram, James; Kahn, Steven E.; Montgomery, Brenda K.; Fujimoto, Wilfred; Knopp, Robert H.; Lipkin, Edward W.; Marr, Michelle; Trence, Dace; Kitabchi, Abbas E.; Murphy, Mary E.; Applegate, William B.; Bryer-Ash, Michael; Frieson, Sandra L.; Imseis, Raed; Lambeth, Helen; Lichtermann, Lynne C.; Oktaei, Hooman; Rutledge, Lily M.K.; Sherman, Amy R.; Smith, Clara M.; Soberman, Judith E.; Williams-Cleaves, Beverly; Metzger, Boyd E.; Johnson, Mariana K.; Behrends, Catherine; Cook, Michelle; Fitzgibbon, Marian; Giles, Mimi M.; Heard, Deloris; Johnson, Cheryl K.H.; Larsen, Diane; Lowe, Anne; Lyman, Megan; McPherson, David; Molitch, Mark E.; Pitts, Thomas; Reinhart, Renee; Roston, Susan; Schinleber, Pamela A.; Nathan, David M.; McKitrick, Charles; Turgeon, Heather; Abbott, Kathy; Anderson, Ellen; Bissett, Laurie; Cagliero, Enrico; Florez, Jose C.; Delahanty, Linda; Goldman, Valerie; Poulos, Alexandra; Olefsky, Jerrold M.; Carrion-Petersen, Mary Lou; Barrett-Connor, Elizabeth; Edelman, Steven V.; Henry, Robert R.; Horne, Javiva; Janesch, Simona Szerdi; Leos, Diana; Mudaliar, Sundar; Polonsky, William; Smith, Jean; Vejvoda, Karen; Pi-Sunyer, F. Xavier; Lee, Jane E.; Allison, David B.; Aronoff, Nancy J.; Crandall, Jill P.; Foo, Sandra T.; Pal, Carmen; Parkes, Kathy; Pena, Mary Beth; Rooney, Ellen S.; Wye, Gretchen E.H. Van; Viscovich, Kristine A.; Marrero, David G.; Prince, Melvin J.; Kelly, Susie M.; Dotson, Yolanda F.; Fineberg, Edwin S.; Guare, John C; Hadden, Angela M.; Ignaut, James M.; Jackson, Marcia L.; Kirkman, Marion S.; Mather, Kieren J.; Porter, Beverly D.; Roach, Paris J.; Rowland, Nancy D.; Wheeler, Madelyn L.; Ratner, Robert E.; Youssef, Gretchen; Shapiro, Sue; Bavido-Arrage, Catherine; Boggs, Geraldine; Bronsord, Marjorie; Brown, Ernestine; Cheatham, Wayman W.; Cola, Susan; Evans, Cindy; Gibbs, Peggy; Kellum, Tracy; Levatan, Claresa; Nair, Asha K.; Passaro, Maureen; Uwaifo, Gabriel; Saad, Mohammed F.; Budget, Maria; Jinagouda, Sujata; Akbar, Khan; Conzues, Claudia; Magpuri, Perpetua; Ngo, Kathy; Rassam, Amer; Waters, Debra; Xapthalamous, Kathy; Santiago, Julio V.; Dagogo-Jack, Samuel; White, Neil H.; Das, Samia; Santiago, Ana; Brown, Angela; Fisher, Edwin; Hurt, Emma; Jones, Tracy; Kerr, Michelle; Ryder, Lucy; Wernimont, Cormarie; Saudek, Christopher D.; Bradley, Vanessa; Sullivan, Emily; Whittington, Tracy; Abbas, Caroline; Brancati, Frederick L.; Clark, Jeanne M.; Charleston, Jeanne B.; Freel, Janice; Horak, Katherine; Jiggetts, Dawn; Johnson, Deloris; Joseph, Hope; Loman, Kimberly; Mosley, Henry; Rubin, Richard R.; Samuels, Alafia; Stewart, Kerry J.; Williamson, Paula; Schade, David S.; Adams, Karwyn S.; Johannes, Carolyn; Atler, Leslie F.; Boyle, Patrick J.; Burge, Mark R.; Canady, Janene L.; Chai, Lisa; Gonzales, Ysela; Hernandez-McGinnis, Doris A.; Katz, Patricia; King, Carolyn; Rassam, Amer; Rubinchik, Sofya; Senter, Willette; Waters, Debra; Shamoon, Harry; Brown, Janet O.; Adorno, Elsie; Cox, Liane; Crandall, Jill; Duffy, Helena; Engel, Samuel; Friedler, Allison; Howard-Century, Crystal J.; Kloiber, Stacey; Longchamp, Nadege; Martinez, Helen; Pompi, Dorothy; Scheindlin, Jonathan; Violino, Elissa; Walker, Elizabeth; Wylie-Rosett, Judith; Zimmerman, Elise; Zonszein, Joel; Orchard, Trevor; Wing, Rena R.; Koenning, Gaye; Kramer, M. Kaye; Barr, Susan; Boraz, Miriam; Clifford, Lisa; Culyba, Rebecca; Frazier, Marlene; Gilligan, Ryan; Harrier, Susan; Harris, Louann; Jeffries, Susan; Kriska, Andrea; Manjoo, Qurashia; Mullen, Monica; Noel, Alicia; Otto, Amy; Semler, Linda; Smith, Cheryl F.; Smith, Marie; Venditti, Elizabeth; Weinzierl, Valarie; Williams, Katherine V.; Wilson, Tara; Arakaki, Richard F.; Latimer, Renee W.; Baker-Ladao, Narleen K.; Beddow, Ralph; Dias, Lorna; Inouye, Jillian; Mau, Marjorie K.; Mikami, Kathy; Mohideen, Pharis; Odom, Sharon K.; Perry, Raynette U.; Knowler, William C.; Cooeyate, Norman; Hoskin, Mary A.; Percy, Carol A.; Acton, Kelly J.; Andre, Vickie L.; Barber, Rosalyn; Begay, Shandiin; Bennett, Peter H.; Benson, Mary Beth; Bird, Evelyn C.; Broussard, Brenda A.; Chavez, Marcella; Dacawyma, Tara; Doughty, Matthew S.; Duncan, Roberta; Edgerton, Cyndy; Ghahate, Jacqueline M.; Glass, Justin; Glass, Martia; Gohdes, Dorothy; Grant, Wendy; Hanson, Robert L.; Horse, Ellie; Ingraham, Louise E.; Jackson, Merry; Jay, Priscilla; Kaskalla, Roylen S.; Kessler, David; Kobus, Kathleen M.; Krakoff, Jonathan; Manus, Catherine; Michaels, Sara; Morgan, Tina; Nashboo, Yolanda; Nelson, Julie A.; Poirier, Steven; Polczynski, Evette; Reidy, Mike; Roumain, Jeanine; Rowse, Debra; Sangster, Sandra; Sewenemewa, Janet; Tonemah, Darryl; Wilson, Charlton; Yazzie, Michelle; Bain, Raymond; Fowler, Sarah; Brenneman, Tina; Abebe, Solome; Bamdad, Julie; Callaghan, Jackie; Edelstein, Sharon L.; Gao, Yuping; Grimes, Kristina L.; Grover, Nisha; Haffner, Lori; Jones, Steve; Jones, Tara L.; Katz, Richard; Lachin, John M.; Mucik, Pamela; Orlosky, Robert; Rochon, James; Sapozhnikova, Alla; Sherif, Hanna; Stimpson, Charlotte; Temprosa, Marinella; Walker-Murray, Fredricka; Marcovina, Santica; Strylewicz, Greg; Aldrich, F. Alan; O'Leary, Dan; Stamm, Elizabeth; Rautaharju, Pentti; Prineas, Ronald J.; Alexander, Teresa; Campbell, Charles; Hall, Sharon; Li, Yabing; Mills, Margaret; Pemberton, Nancy; Rautaharju, Farida; Zhang, Zhuming; Mayer-Davis, Elizabeth; Moran, Robert R.; Ganiats, Ted; David, Kristin; Sarkin, Andrew J.; Eastman, R.; Fradkin, Judith; Garfield, Sanford; Gregg, Edward; Zhang, Ping; Herman, William; Florez, Jose C.; Altshuler, David; de Bakker, Paul I.W.; Franks, Paul W.; Hanson, Robert L.; Jablonski, Kathleen; Knowler, William C.; McAteer, Jarred B.; Pollin, Toni I.; Shuldiner, Alan R.

2012-01-01

Weight-loss interventions generally improve lipid profiles and reduce cardiovascular disease risk, but effects are variable and may depend on genetic factors. We performed a genetic association analysis of data from 2,993 participants in the Diabetes Prevention Program to test the hypotheses that a genetic risk score (GRS) based on deleterious alleles at 32 lipid-associated single-nucleotide polymorphisms modifies the effects of lifestyle and/or metformin interventions on lipid levels and nuclear magnetic resonance (NMR) lipoprotein subfraction size and number. Twenty-three loci previously associated with fasting LDL-C, HDL-C, or triglycerides replicated (P = 0.04–1×10−17). Except for total HDL particles (r = −0.03, P = 0.26), all components of the lipid profile correlated with the GRS (partial |r| = 0.07–0.17, P = 5×10−5–1×10−19). The GRS was associated with higher baseline-adjusted 1-year LDL cholesterol levels (β = +0.87, SEE±0.22 mg/dl/allele, P = 8×10−5, P interaction = 0.02) in the lifestyle intervention group, but not in the placebo (β = +0.20, SEE±0.22 mg/dl/allele, P = 0.35) or metformin (β = −0.03, SEE±0.22 mg/dl/allele, P = 0.90; P interaction = 0.64) groups. Similarly, a higher GRS predicted a greater number of baseline-adjusted small LDL particles at 1 year in the lifestyle intervention arm (β = +0.30, SEE±0.012 ln nmol/L/allele, P = 0.01, P interaction = 0.01) but not in the placebo (β = −0.002, SEE±0.008 ln nmol/L/allele, P = 0.74) or metformin (β = +0.013, SEE±0.008 nmol/L/allele, P = 0.12; P interaction = 0.24) groups. Our findings suggest that a high genetic burden confers an adverse lipid profile and predicts attenuated response in LDL-C levels and small LDL particle number to dietary and physical activity interventions aimed at weight loss. PMID:22951888

Genetic variability in MCF-7 sublines: evidence of rapid genomic and RNA expression profile modifications

International Nuclear Information System (INIS)

Nugoli, Mélanie; Theillet, Charles; Chuchana, Paul; Vendrell, Julie; Orsetti, Béatrice; Ursule, Lisa; Nguyen, Catherine; Birnbaum, Daniel; Douzery, Emmanuel JP; Cohen, Pascale

2003-01-01

Both phenotypic and cytogenetic variability have been reported for clones of breast carcinoma cell lines but have not been comprehensively studied. Despite this, cell lines such as MCF-7 cells are extensively used as model systems. In this work we documented, using CGH and RNA expression profiles, the genetic variability at the genomic and RNA expression levels of MCF-7 cells of different origins. Eight MCF-7 sublines collected from different sources were studied as well as 3 subclones isolated from one of the sublines by limit dilution. MCF-7 sublines showed important differences in copy number alteration (CNA) profiles. Overall numbers of events ranged from 28 to 41. Involved chromosomal regions varied greatly from a subline to another. A total of 62 chromosomal regions were affected by either gains or losses in the 11 sublines studied. We performed a phylogenetic analysis of CGH profiles using maximum parsimony in order to reconstruct the putative filiation of the 11 MCF-7 sublines. The phylogenetic tree obtained showed that the MCF-7 clade was characterized by a restricted set of 8 CNAs and that the most divergent subline occupied the position closest to the common ancestor. Expression profiles of 8 MCF-7 sublines were analyzed along with those of 19 unrelated breast cancer cell lines using home made cDNA arrays comprising 720 genes. Hierarchical clustering analysis of the expression data showed that 7/8 MCF-7 sublines were grouped forming a cluster while the remaining subline clustered with unrelated breast cancer cell lines. These data thus showed that MCF-7 sublines differed at both the genomic and phenotypic levels. The analysis of CGH profiles of the parent subline and its three subclones supported the heteroclonal nature of MCF-7 cells. This strongly suggested that the genetic plasticity of MCF-7 cells was related to their intrinsic capacity to generate clonal heterogeneity. We propose that MCF-7, and possibly the breast tumor it was derived from, evolved

Sequence-engineered mRNA Without Chemical Nucleoside Modifications Enables an Effective Protein Therapy in Large Animals

OpenAIRE

Thess, Andreas; Grund, Stefanie; Mui, Barbara L; Hope, Michael J; Baumhof, Patrick; Fotin-Mleczek, Mariola; Schlake, Thomas

2015-01-01

Being a transient carrier of genetic information, mRNA could be a versatile, flexible, and safe means for protein therapies. While recent findings highlight the enormous therapeutic potential of mRNA, evidence that mRNA-based protein therapies are feasible beyond small animals such as mice is still lacking. Previous studies imply that mRNA therapeutics require chemical nucleoside modifications to obtain sufficient protein expression and avoid activation of the innate immune system. Here we sh...

Hypothetical link between infertility and genetically modified food.

Science.gov (United States)

Gao, Mingxia; Li, Bin; Yuan, Wenzhen; Zhao, Lihui; Zhang, Xuehong

2014-01-01

It is speculated that genetically modified food (GMF)/genetically modified organism (GMO) is responsible for infertility development. The risk linked with a wide use of GMFs/GMOs offers the basic elements for social criticism. However, to date, it has not been justified whether the bad effects are directly resulted from products of genetic modifications or trans-genesis process. Extensive experience with the risk assessment of whole foods has been applied recently on the safety and nutritional testing of GMFs/GMOs. Investigations have tested the safety of GMFs including sub-acute, chronic, reproductive, multi-generation and carcinogenicity studies. We extrapolated the potential risks associated with GMFs/GMOs on reproduction, and analyzed the multi-aspect linked between infertility and GMFs/GMOs. It could be conjectured that GMFs/GMOs could be potential hazard on reproduction, linking to the development of infertility through influencing the endocrine metabolism, endometriosis. However, little evidence shows the impaction on embryo or reproductive related tumor due to the limited literatures, and needs further research. The article presents some related patents on GMFs/GMOs, and some methods for tracking GMOs.

Specific genetic modifications of domestic animals by gene targeting and animal cloning

Directory of Open Access Journals (Sweden)

Zhou Jiangfeng

2003-11-01

Full Text Available Abstract The technology of gene targeting through homologous recombination has been extremely useful for elucidating gene functions in mice. The application of this technology was thought impossible in the large livestock species until the successful creation of the first mammalian clone "Dolly" the sheep. The combination of the technologies for gene targeting of somatic cells with those of animal cloning made it possible to introduce specific genetic mutations into domestic animals. In this review, the principles of gene targeting in somatic cells and the challenges of nuclear transfer using gene-targeted cells are discussed. The relevance of gene targeting in domestic animals for applications in bio-medicine and agriculture are also examined.

Behavior of restriction–modification systems as selfish mobile elements and their impact on genome evolution

Science.gov (United States)

Kobayashi, Ichizo

2001-01-01

Restriction–modification (RM) systems are composed of genes that encode a restriction enzyme and a modification methylase. RM systems sometimes behave as discrete units of life, like viruses and transposons. RM complexes attack invading DNA that has not been properly modified and thus may serve as a tool of defense for bacterial cells. However, any threat to their maintenance, such as a challenge by a competing genetic element (an incompatible plasmid or an allelic homologous stretch of DNA, for example) can lead to cell death through restriction breakage in the genome. This post-segregational or post-disturbance cell killing may provide the RM complexes (and any DNA linked with them) with a competitive advantage. There is evidence that they have undergone extensive horizontal transfer between genomes, as inferred from their sequence homology, codon usage bias and GC content difference. They are often linked with mobile genetic elements such as plasmids, viruses, transposons and integrons. The comparison of closely related bacterial genomes also suggests that, at times, RM genes themselves behave as mobile elements and cause genome rearrangements. Indeed some bacterial genomes that survived post-disturbance attack by an RM gene complex in the laboratory have experienced genome rearrangements. The avoidance of some restriction sites by bacterial genomes may result from selection by past restriction attacks. Both bacteriophages and bacteria also appear to use homologous recombination to cope with the selfish behavior of RM systems. RM systems compete with each other in several ways. One is competition for recognition sequences in post-segregational killing. Another is super-infection exclusion, that is, the killing of the cell carrying an RM system when it is infected with another RM system of the same regulatory specificity but of a different sequence specificity. The capacity of RM systems to act as selfish, mobile genetic elements may underlie the structure and

Behavior of restriction-modification systems as selfish mobile elements and their impact on genome evolution.

Science.gov (United States)

Kobayashi, I

2001-09-15

Restriction-modification (RM) systems are composed of genes that encode a restriction enzyme and a modification methylase. RM systems sometimes behave as discrete units of life, like viruses and transposons. RM complexes attack invading DNA that has not been properly modified and thus may serve as a tool of defense for bacterial cells. However, any threat to their maintenance, such as a challenge by a competing genetic element (an incompatible plasmid or an allelic homologous stretch of DNA, for example) can lead to cell death through restriction breakage in the genome. This post-segregational or post-disturbance cell killing may provide the RM complexes (and any DNA linked with them) with a competitive advantage. There is evidence that they have undergone extensive horizontal transfer between genomes, as inferred from their sequence homology, codon usage bias and GC content difference. They are often linked with mobile genetic elements such as plasmids, viruses, transposons and integrons. The comparison of closely related bacterial genomes also suggests that, at times, RM genes themselves behave as mobile elements and cause genome rearrangements. Indeed some bacterial genomes that survived post-disturbance attack by an RM gene complex in the laboratory have experienced genome rearrangements. The avoidance of some restriction sites by bacterial genomes may result from selection by past restriction attacks. Both bacteriophages and bacteria also appear to use homologous recombination to cope with the selfish behavior of RM systems. RM systems compete with each other in several ways. One is competition for recognition sequences in post-segregational killing. Another is super-infection exclusion, that is, the killing of the cell carrying an RM system when it is infected with another RM system of the same regulatory specificity but of a different sequence specificity. The capacity of RM systems to act as selfish, mobile genetic elements may underlie the structure and

The management of modifications

International Nuclear Information System (INIS)

Bernard, C.

1992-01-01

Description of the management methods of modifications at EDF. To maintain safety standards of the nuclear power station the 'Direction de l'Equipment' and the 'Direction du Parc en Exploitation' have jointly fixed the modalities of management for all modifications and recorded them in a 'Practical Guide'

Variables Affecting Secondary School Students' Willingness to Eat Genetically Modified Food Crops

Science.gov (United States)

Maes, Jasmien; Bourgonjon, Jeroen; Gheysen, Godelieve; Valcke, Martin

2017-04-01

A large-scale cross-sectional study (N = 4002) was set up to determine Flemish secondary school students' willingness to eat genetically modified food (WTE) and to link students' WTE to previously identified key variables from research on the acceptance of genetic modification (GM). These variables include subjective and objective knowledge about genetics and biotechnology, perceived risks and benefits of GM food crops, trust in information from different sources about GM, and food neophobia. Differences between WTE-related variables based on students' grade level, educational track, and gender were analyzed. The students displayed a rather indecisive position toward GM food and scored weakly on a genetics and biotechnology knowledge test. WTE correlated most strongly with perceived benefits and subjective and objective knowledge. The results have clear implications for education, as they reiterate the need to strengthen students' scientific knowledge base and to introduce a GM-related debate at a much earlier stage in their school career.

Directional cultural change by modification and replacement of memes.

Science.gov (United States)

Cardoso, Gonçalo C; Atwell, Jonathan W

2011-01-01

Evolutionary approaches to culture remain contentious. A source of contention is that cultural mutation may be substantial and, if it drives cultural change, then current evolutionary models are not adequate. But we lack studies quantifying the contribution of mutations to directional cultural change. We estimated the contribution of one type of cultural mutations--modification of memes--to directional cultural change using an amenable study system: learned birdsongs in a species that recently entered an urban habitat. Many songbirds have higher minimum song frequency in cities, to alleviate masking by low-frequency noise. We estimated that the input of meme modifications in an urban songbird population explains about half the extent of the population divergence in song frequency. This contribution of cultural mutations is large, but insufficient to explain the entire population divergence. The remaining divergence is due to selection of memes or creation of new memes. We conclude that the input of cultural mutations can be quantitatively important, unlike in genetic evolution, and that it operates together with other mechanisms of cultural evolution. For this and other traits, in which the input of cultural mutations might be important, quantitative studies of cultural mutation are necessary to calibrate realistic models of cultural evolution. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

Food safety evaluation of crops produced through genetic engineering--how to reduce unintended effects?

Science.gov (United States)

Jelenić, Srećko

2005-06-01

Scientists started applying genetic engineering techniques to improve crops two decades ago; about 70 varieties obtained via genetic engineering have been approved to date. Although genetic engineering offers the most precise and controllable genetic modification of crops in entire history of plant improvement, the site of insertion of a desirable gene cannot be predicted during the application of this technology. As a consequence, unintended effects might occur due to activation or silencing of genes, giving rise to allergic reactions or toxicity. Therefore, extensive chemical, biochemical and nutritional analyses are performed on each new genetically engineered variety. Since the unintended effects may be predictable on the basis of what is known about the insertion place of the transgenic DNA, an important aim of plant biotechnology is to define techniques for the insertion of transgene into the predetermined chromosomal position (gene targeting). Although gene targeting cannot be applied routinely in crop plants, given the recent advances, that goal may be reached in the near future.

Genetic modification of mesenchymal stem cells overexpressing CCR1 increases cell viability, migration, engraftment, and capillary density in the injured myocardium.

Science.gov (United States)

Huang, Jing; Zhang, Zhiping; Guo, Jian; Ni, Aiguo; Deb, Arjun; Zhang, Lunan; Mirotsou, Maria; Pratt, Richard E; Dzau, Victor J

2010-06-11

Although mesenchymal stem cell (MSC) transplantation has been shown to promote cardiac repair in acute myocardial injury in vivo, its overall restorative capacity appears to be restricted mainly because of poor cell viability and low engraftment in the ischemic myocardium. Specific chemokines are upregulated in the infarcted myocardium. However the expression levels of the corresponding chemokine receptors (eg, CCR1, CXCR2) in MSCs are very low. We hypothesized that this discordance may account for the poor MSC engraftment and survival. To determine whether overexpression of CCR1 or CXCR2 chemokine receptors in MSCs augments their cell survival, migration and engraftment after injection in the infarcted myocardium. Overexpression of CCR1, but not CXCR2, dramatically increased chemokine-induced murine MSC migration and protected MSC from apoptosis in vitro. Moreover, when MSCs were injected intramyocardially one hour after coronary artery ligation, CCR1-MSCs accumulated in the infarcted myocardium at significantly higher levels than control-MSCs or CXCR2-MSCs 3 days postmyocardial infarction (MI). CCR1-MSC-injected hearts exhibited a significant reduction in infarct size, reduced cardiomyocytes apoptosis and increased capillary density in injured myocardium 3 days after MI. Furthermore, intramyocardial injection of CCR1-MSCs prevented cardiac remodeling and restored cardiac function 4 weeks after MI. Our results demonstrate the in vitro and in vivo salutary effects of genetic modification of stem cells. Specifically, overexpression of chemokine receptor enhances the migration, survival and engraftment of MSCs, and may provide a new therapeutic strategy for the injured myocardium.

Deciphering the Translation Initiation Factor 5A Modification Pathway in Halophilic Archaea

Directory of Open Access Journals (Sweden)

Laurence Prunetti

2016-01-01

Full Text Available Translation initiation factor 5A (IF5A is essential and highly conserved in Eukarya (eIF5A and Archaea (aIF5A. The activity of IF5A requires hypusine, a posttranslational modification synthesized in Eukarya from the polyamine precursor spermidine. Intracellular polyamine analyses revealed that agmatine and cadaverine were the main polyamines produced in Haloferax volcanii in minimal medium, raising the question of how hypusine is synthesized in this halophilic Archaea. Metabolic reconstruction led to a tentative picture of polyamine metabolism and aIF5A modification in Hfx. volcanii that was experimentally tested. Analysis of aIF5A from Hfx. volcanii by LC-MS/MS revealed it was exclusively deoxyhypusinylated. Genetic studies confirmed the role of the predicted arginine decarboxylase gene (HVO_1958 in agmatine synthesis. The agmatinase-like gene (HVO_2299 was found to be essential, consistent with a role in aIF5A modification predicted by physical clustering evidence. Recombinant deoxyhypusine synthase (DHS from S. cerevisiae was shown to transfer 4-aminobutyl moiety from spermidine to aIF5A from Hfx. volcanii in vitro. However, at least under conditions tested, this transfer was not observed with the Hfx. volcanii DHS. Furthermore, the growth of Hfx. volcanii was not inhibited by the classical DHS inhibitor GC7. We propose a model of deoxyhypusine synthesis in Hfx. volcanii that differs from the canonical eukaryotic pathway, paving the way for further studies.

Human Rights and Behavior Modification

Science.gov (United States)

Roos, Philip

1974-01-01

Criticisms of behavior modification, which charge that it violates ethical and legal principles, are discussed and reasons are presented to explain behavior modification's susceptibility to attack. (GW)

Restriction-modification mediated barriers to exogenous DNA uptake and incorporation employed by Prevotella intermedia.

Science.gov (United States)

Johnston, Christopher D; Skeete, Chelsey A; Fomenkov, Alexey; Roberts, Richard J; Rittling, Susan R

2017-01-01

Prevotella intermedia, a major periodontal pathogen, is increasingly implicated in human respiratory tract and cystic fibrosis lung infections. Nevertheless, the specific mechanisms employed by this pathogen remain only partially characterized and poorly understood, largely due to its total lack of genetic accessibility. Here, using Single Molecule, Real-Time (SMRT) genome and methylome sequencing, bisulfite sequencing, in addition to cloning and restriction analysis, we define the specific genetic barriers to exogenous DNA present in two of the most widespread laboratory strains, P. intermedia ATCC 25611 and P. intermedia Strain 17. We identified and characterized multiple restriction-modification (R-M) systems, some of which are considerably divergent between the two strains. We propose that these R-M systems are the root cause of the P. intermedia transformation barrier. Additionally, we note the presence of conserved Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) systems in both strains, which could provide a further barrier to exogenous DNA uptake and incorporation. This work will provide a valuable resource during the development of a genetic system for P. intermedia, which will be required for fundamental investigation of this organism's physiology, metabolism, and pathogenesis in human disease.

GRFT – Genetic records family tree web applet

Directory of Open Access Journals (Sweden)

Samuel ePimentel

2011-03-01

Full Text Available Current software for storing and displaying records of genetic crosses does not provide an easy way to determine the lineage of an individual. The genetic records family tree (GRFT applet processes records of genetic crosses and allows researchers to quickly visualize lineages using a family tree construct and to access other information from these records using any Internet browser. Users select from three display features: 1 a family tree view which displays a color-coded family tree for an individual, 2 a sequential list of crosses, and 3 a list of crosses matching user-defined search criteria. Each feature contains options to specify the number of records shown and the latter two contain an option to filter results by the owner of the cross. The family tree feature is interactive, displaying a popup box with genetic information when the user mouses over an individual and allowing the user to draw a new tree by clicking on any individual in the current tree. The applet is written in Javascript and reads genetic records from a tab-delimited text file on the server, so it is cross-platform, can be accessed by anyone with an Internet connection, and supports almost instantaneous generation of new trees and table lists. Researchers can use the tool with their own genetic cross records for any sexually-reproducing organism. No additional software is required and with only minor modifications to the script, researchers can add their own custom columns. GRFT's speed, versatility, and low overhead make it an effective and innovative visualization method for genetic records. A sample tool is available at http://stanford.edu/~walbot/grft-sample.html.

Gene therapy in dentistry: tool of genetic engineering. Revisited.

Science.gov (United States)

Gupta, Khushboo; Singh, Saurabh; Garg, Kavita Nitish

2015-03-01

Advances in biotechnology have brought gene therapy to the forefront of medical research. The concept of transferring genes to tissues for clinical applications has been discussed nearly half a century, but the ability to manipulate genetic material via recombinant DNA technology has brought this goal to reality. The feasibility of gene transfer was first demonstrated using tumour viruses. This led to development of viral and nonviral methods for the genetic modification of somatic cells. Applications of gene therapy to dental and oral problems illustrate the potential impact of this technology on dentistry. Preclinical trial results regarding the same have been very promising. In this review we will discuss methods, vectors involved, clinical implication in dentistry and scientific issues associated with gene therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Behavior Modification in the Classroom

Science.gov (United States)

Whitman, Mryon; Whitman, Joan

1971-01-01

This article presents the theoretical rationale for behavior modification, principally through its comparison with traditional psychotherapies, and suggests some behavior modification techniques for the classroom management of maladaptive behavior. (Author)

A Key Opinion Leaders Analysis of the Critical Success Factors for the Market Potential of Genetically Modified Vaccines

NARCIS (Netherlands)

Ramezanpour, B.; Kamphuis, Pim; Claassen, H.J.H.M.

2016-01-01

Conventional vaccines have been very successful in preventing and controlling many diseases. One of the next steps in vaccine innovation is the introduction of genetic modification, which provides various novel opportunities in the vaccine field. Although the market potential for conventional

A nursing theory-guided framework for genetic and epigenetic research.

Science.gov (United States)

Maki, Katherine A; DeVon, Holli A

2018-04-01

The notion that genetics, through natural selection, determines innate traits has led to much debate and divergence of thought on the impact of innate traits on the human phenotype. The purpose of this synthesis was to examine how innate theory informs genetic research and how understanding innate theory through the lens of Martha Rogers' theory of unitary human beings can offer a contemporary view of how innate traits can inform epigenetic and genetic research. We also propose a new conceptual model for genetic and epigenetic research. The philosophical, theoretical, and research literatures were examined for this synthesis. We have merged philosophical and conceptual phenomena from innate theory with the theory of unitary beings into the University of Illinois at Chicago model for genetic and epigenetic research. Innate traits are the cornerstone of the framework but may be modified epigenetically by biological, physiological, psychological, and social determinants as they are transcribed. These modifiers serve as important links between the concept of innate traits and epigenetic modifications, and, like the theory of unitary human beings, the process is understood in the context of individual and environmental interaction that has the potential to evolve as the determinants change. © 2018 John Wiley & Sons Ltd.

Evidence for Absolute Moral Opposition to Genetically Modified Food in the United States.

Science.gov (United States)

Scott, Sydney E; Inbar, Yoel; Rozin, Paul

2016-05-01

Public opposition to genetic modification (GM) technology in the food domain is widespread (Frewer et al., 2013). In a survey of U.S. residents representative of the population on gender, age, and income, 64% opposed GM, and 71% of GM opponents (45% of the entire sample) were "absolutely" opposed-that is, they agreed that GM should be prohibited no matter the risks and benefits. "Absolutist" opponents were more disgust sensitive in general and more disgusted by the consumption of genetically modified food than were non-absolutist opponents or supporters. Furthermore, disgust predicted support for legal restrictions on genetically modified foods, even after controlling for explicit risk-benefit assessments. This research suggests that many opponents are evidence insensitive and will not be influenced by arguments about risks and benefits. © The Author(s) 2016.

MODIFICATION OF PAPERMAKING GRADE FILLERS: A BRIEF REVIEW

Directory of Open Access Journals (Sweden)

Jing Shen

2009-08-01

Full Text Available The use of fillers in paper products can provide cost and energy savings, improved paper properties, increased productivities, and specifically desired paper functionalities. There are many problems associated with the use of fillers, such as unsuitability of calcium carbonate fillers in acid papermaking, negative effects of filler loading on paper strength, sizing, and retention, and tendencies of fillers to cause abrasion and dusting. In order to solve these problems and to make better use of fillers, many methods have been proposed, among which filler modification has been a hot topic. The available technologies of filler modification mainly include modification with inorganic substances, modification with natural polymers or their derivatives, modification with water-soluble synthetic polymers, modification with surfactants, modification with polymer latexes, hydrophobic modification, cationic modification, surface nano-structuring, physical modification by compressing, calcination or grinding, and modification for use in functional papers. The methods of filler modification can provide improved acid tolerant and optical properties of fillers, enhanced fiber-filler bonding, improved filler retention and filler sizabilities, alleviated filler abrasiveness, improved filler dispersability, and functionalization of filled papers. Filler modification has been an indispensable way to accelerate the development of high filler technology in papermaking, which is likely to create additional benefits to papermaking industry in the future.

Unintended compositional changes in genetically modified (GM) crops: 20 years of research.

Science.gov (United States)

Herman, Rod A; Price, William D

2013-12-04

The compositional equivalency between genetically modified (GM) crops and nontransgenic comparators has been a fundamental component of human health safety assessment for 20 years. During this time, a large amount of information has been amassed on the compositional changes that accompany both the transgenesis process and traditional breeding methods; additionally, the genetic mechanisms behind these changes have been elucidated. After two decades, scientists are encouraged to objectively assess this body of literature and determine if sufficient scientific uncertainty still exists to continue the general requirement for these studies to support the safety assessment of transgenic crops. It is concluded that suspect unintended compositional effects that could be caused by genetic modification have not materialized on the basis of this substantial literature. Hence, compositional equivalence studies uniquely required for GM crops may no longer be justified on the basis of scientific uncertainty.

Scientific Opinion on Lipase from a Genetically Modified Strain of Aspergillus oryzae (strain NZYM-LH)

OpenAIRE

EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

2014-01-01

The food enzyme considered in this opinion is a lipase (triacylglycerol lipase; EC 3.1.1.3) produced with a genetically modified strain of Aspergillus oryzae. The genetic modifications do not raise safety concern. The food enzyme contains neither the production organism nor recombinant DNA. The lipase is intended to be used in a number of food manufacturing processes, such as in baking and other cereal-based processes. The dietary exposure was assessed on the basis of data retrieved from the ...

Genetically modified soybeans and food allergies.

Science.gov (United States)

Herman, Eliot M

2003-05-01

Allergenic reactions to proteins expressed in GM crops has been one of the prominent concerns among biotechnology critics and a concern of regulatory agencies. Soybeans like many plants have intrinsic allergens that present problems for sensitive people. Current GM crops, including soybean, have not been shown to add any additional allergenic risk beyond the intrinsic risks already present. Biotechnology can be used to characterize and eliminate allergens naturally present in crops. Biotechnology has been used to remove a major allergen in soybean demonstrating that genetic modification can be used to reduce allergenicity of food and feed. This provides a model for further use of GM approaches to eliminate allergens.

Behaviour of wild-type and genetically modified baculoviruses in the Helicoverpa armigera - cotton system: a simulation approach

NARCIS (Netherlands)

Sun, X.

2005-01-01

Keywords:   Helicoverpa armigera , baculovirus, genetic modification, cotton,transmission

Comparative genomic and phylogenetic approaches to characterize the role of genetic recombination in mycobacterial evolution.

Science.gov (United States)

Smith, Silvia E; Showers-Corneli, Patrice; Dardenne, Caitlin N; Harpending, Henry H; Martin, Darren P; Beiko, Robert G

2012-01-01

The genus Mycobacterium encompasses over one hundred named species of environmental and pathogenic organisms, including the causative agents of devastating human diseases such as tuberculosis and leprosy. The success of these human pathogens is due in part to their ability to rapidly adapt to their changing environment and host. Recombination is the fastest way for bacterial genomes to acquire genetic material, but conflicting results about the extent of recombination in the genus Mycobacterium have been reported. We examined a data set comprising 18 distinct strains from 13 named species for evidence of recombination. Genomic regions common to all strains (accounting for 10% to 22% of the full genomes of all examined species) were aligned and concatenated in the chromosomal order of one mycobacterial reference species. The concatenated sequence was screened for evidence of recombination using a variety of statistical methods, with each proposed event evaluated by comparing maximum-likelihood phylogenies of the recombinant section with the non-recombinant portion of the dataset. Incongruent phylogenies were identified by comparing the site-wise log-likelihoods of each tree using multiple tests. We also used a phylogenomic approach to identify genes that may have been acquired through horizontal transfer from non-mycobacterial sources. The most frequent associated lineages (and potential gene transfer partners) in the Mycobacterium lineage-restricted gene trees are other members of suborder Corynebacterinae, but more-distant partners were identified as well. In two examined cases of potentially frequent and habitat-directed transfer (M. abscessus to Segniliparus and M. smegmatis to Streptomyces), observed sequence distances were small and consistent with a hypothesis of transfer, while in a third case (M. vanbaalenii to Streptomyces) distances were larger. The analyses described here indicate that whereas evidence of recombination in core regions within the genus is

Experimental evolution and the dynamics of genomic mutation rate modifiers.

Science.gov (United States)

Raynes, Y; Sniegowski, P D

2014-11-01

Because genes that affect mutation rates are themselves subject to mutation, mutation rates can be influenced by natural selection and other evolutionary forces. The population genetics of mutation rate modifier alleles has been a subject of theoretical interest for many decades. Here, we review experimental contributions to our understanding of mutation rate modifier dynamics. Numerous evolution experiments have shown that mutator alleles (modifiers that elevate the genomic mutation rate) can readily rise to high frequencies via genetic hitchhiking in non-recombining microbial populations. Whereas these results certainly provide an explanatory framework for observations of sporadically high mutation rates in pathogenic microbes and in cancer lineages, it is nonetheless true that most natural populations have very low mutation rates. This raises the interesting question of how mutator hitchhiking is suppressed or its phenotypic effect reversed in natural populations. Very little experimental work has addressed this question; with this in mind, we identify some promising areas for future experimental investigation.

Modifications to Replacement Costs System

International Nuclear Information System (INIS)

Godec, M.

1989-01-01

The purpose of this memorandum is to document the improvements and modifications made to the Replacement Costs of Crude Oil (REPCO) Supply Analysis System. While some of this work was performed under our previous support contract to DOE/ASFE, we are presenting all modifications and improvements are presented here for completeness. The memo primarily documents revisions made to the Lower-48 Onshore Model. Revisions and modifications made to other components and models in the REPCO system which are documented elsewhere are only highlighted in this memo. Generally, the modifications made to the Lower-48 Onshore Model reflect changes that have occurred in domestic drilling, oil field costs, and reserves since 1982, the date of the most recent available data used for the original Replacement Costs report, published in 1985

Influence of race/ethnicity on genetic counseling and testing for hereditary breast and ovarian cancer.

Science.gov (United States)

Forman, Andrea D; Hall, Michael J

2009-01-01

Risk assessment coupled with genetic counseling and testing for the cancer predisposition genes BRCA1 and BRCA2 (BRCA1/2) has become an integral element of comprehensive patient evaluation and cancer risk management in the United States for individuals meeting high-risk criteria for hereditary breast and ovarian cancer (HBOC). For mutation carriers, several options for risk modification have achieved substantial reductions in future cancer risk. However, several recent studies have shown lower rates of BRCA1/2 counseling and testing among minority populations. Here, we explore the role of race/ethnicity in cancer risk assessment, genetic counseling and genetic testing for HBOC and the BRCA1/2 cancer predisposition genes. Barriers to genetic services related to race/ethnicity and underserved populations, including socioeconomic barriers (e.g., time, access, geographic, language/cultural, awareness, cost) and psychosocial barriers (e.g., medical mistrust, perceived disadvantages to genetic services), as well as additional barriers to care once mutation carriers are identified, will be reviewed.

Value-impact assessment of safety-related modifications

International Nuclear Information System (INIS)

Knowles, W.M.C.; Dinnie, K.S.; Gordon, C.W.

1992-01-01

Like other nuclear utilities, Ontario Hydro, as part of its risk management activities, continually assesses the safety of its nuclear operations. In addition, new regulatory requirements are being applied to the older nuclear power plants. Both of these result in proposed plant modifications designed to reduce the risk to the public. However, modifications to an operating plant can have serious economic effects, and the resources, both financial and personnel, required for the implementation of these modifications are limited. Thus, all potential benefits and effects of a proposed modification must be thoroughly investigated to judge whether the modification is beneficial. Ontario Hydro has begun to use comprehensive value-impact assessments, utilizing plant-specific probabilistic risk assessments (PRAs), as tools to provide an informed basis for judgments on the benefit of safety-related modifications. The results from value-impact assessments can also be used to prioritize the implementation of these modifications

Epigenetic modification of the oxytocin and glucocorticoid receptor genes is linked to attachment avoidance in young adults.

Science.gov (United States)

Ein-Dor, Tsachi; Verbeke, Willem J M I; Mokry, Michal; Vrtička, Pascal

2018-08-01

Attachment in the context of intimate pair bonds is most frequently studied in terms of the universal strategy to draw near, or away, from significant others at moments of personal distress. However, important interindividual differences in the quality of attachment exist, usually captured through secure versus insecure - anxious and/or avoidant - attachment orientations. Since Bowlby's pioneering writings on the theory of attachment, it has been assumed that attachment orientations are influenced by both genetic and social factors - what we would today describe and measure as gene by environment interaction mediated by epigenetic DNA modification - but research in humans on this topic remains extremely limited. We for the first time examined relations between intra-individual differences in attachment and epigenetic modification of the oxytocin receptor (OXTR) and glucocorticoid receptor (NR3C1) gene promoter in 109 young adult human participants. Our results revealed that attachment avoidance was significantly and specifically associated with increased OXTR and NR3C1 promoter methylation. These findings offer first tentative clues on the possible etiology of attachment avoidance in humans by showing epigenetic modification in genes related to both social stress regulation and HPA axis functioning.

Modification of Sr on 4004 Aluminum Alloy

Science.gov (United States)

Guo, Erjun; Cao, Guojian; Feng, Yicheng; Wang, Liping; Wang, Guojun; Lv, Xinyu

2013-05-01

As a brazing foil, 4004 Al alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. To improve the plasticity of 4004 Al alloy and subsequently improve the productivity of 4004 Al foil or 434 composite foil, 4004 Al alloy was modified by Al-10%Sr master alloy. Modification effects of an additional amount of Sr, modification temperature, and holding time on 4004 aluminum alloy were studied by orthogonal design. The results showed that the greatest impact parameter of 4004 aluminum alloy modification was the additional amount of Sr, followed by holding time and modification temperature. The optimum modification parameters obtained by orthogonal design were as follows: Sr addition of 0.04%, holding time of 60 min, and modification temperature of 760°C. The effect of Sr addition on modification was analyzed in detail based on orthogonal results. With increasing of Sr addition, elongation of 4004 alloy increased at first, and decreased after reaching the maximum value.

Chemical Modifications of Starch: Microwave Effect

Directory of Open Access Journals (Sweden)

Kamila Lewicka

2015-01-01

Full Text Available This paper presents basic methods of starch chemical modification, the effect of microwave radiation on the modification process, and the physicochemical properties of starch. It has been shown that the modifications contribute to improvement of the material performance and likewise to significant improvement of its mechanical properties. As a result, more and more extensive use of starch is possible in various industries. In addition, methods of oxidized starch and starch esters preparation are discussed. Properties of microwave radiation and its impact on starch (with particular regard to modifications described in literature are characterized.

EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2014. Scientific Opinion on lipase from a genetically modified strain of Aspergillus oryzae (strain NZYM-FL)

DEFF Research Database (Denmark)

Poulsen, Morten; Hallas-Møller, Torben; Binderup, Mona-Lise

The food enzyme considered in this opinion is a lipase (triacylglycerol lipase; EC 3.1.1.3) produced with a genetically modified strain of Aspergillus oryzae. The genetic modifications do not raise safety concern. The food enzyme contains neither the production organism nor recombinant DNA...

Modification Semantics in Now-Relative Databases

DEFF Research Database (Denmark)

Torp, Kristian; Jensen, Christian Søndergaard; Snodgrass, R. T.

2004-01-01

Most real-world databases record time-varying information. In such databases, the notion of ??the current time,?? or NOW, occurs naturally and prominently. For example, when capturing the past states of a relation using begin and end time columns, tuples that are part of the current state have some...... past time as their begin time and NOW as their end time. While the semantics of such variable databases has been described in detail and is well understood, the modification of variable databases remains unexplored. This paper defines the semantics of modifications involving the variable NOW. More...... specifically,  the problems with modifications in the presence of NOW are explored, illustrating that the main problems are with modifications of tuples that reach into the future. The paper defines the semantics of modifications?including insertions, deletions, and updates?of databases without NOW, with NOW...

Norway spruce (Picea abies) genetic transformation with modified Cry3A gene of Bacillus thuringiensis

Czech Academy of Sciences Publication Activity Database

Bříza, Jindřich; Pavingerová, Daniela; Vlasák, Josef; Niedermeierová, Hana

2013-01-01

Roč. 60, č. 3 (2013), s. 395-400 ISSN 0001-527X R&D Projects: GA MZe QH71290; GA ČR(CZ) GAP502/11/1471 Institutional support: RVO:60077344 Keywords : Cry3A gene modification * Picea abies * Agrobacterium tumefaciens Subject RIV: EB - Genetic s ; Molecular Biology Impact factor: 1.389, year: 2013

Hybridizing Differential Evolution with a Genetic Algorithm for Color Image Segmentation

Directory of Open Access Journals (Sweden)

R. V. V. Krishna

2016-10-01

Full Text Available This paper proposes a hybrid of differential evolution and genetic algorithms to solve the color image segmentation problem. Clustering based color image segmentation algorithms segment an image by clustering the features of color and texture, thereby obtaining accurate prototype cluster centers. In the proposed algorithm, the color features are obtained using the homogeneity model. A new texture feature named Power Law Descriptor (PLD which is a modification of Weber Local Descriptor (WLD is proposed and further used as a texture feature for clustering. Genetic algorithms are competent in handling binary variables, while differential evolution on the other hand is more efficient in handling real parameters. The obtained texture feature is binary in nature and the color feature is a real value, which suits very well the hybrid cluster center optimization problem in image segmentation. Thus in the proposed algorithm, the optimum texture feature centers are evolved using genetic algorithms, whereas the optimum color feature centers are evolved using differential evolution.

Epigenetic modification and inheritance in sexual reversal of fish.

Science.gov (United States)

Shao, Changwei; Li, Qiye; Chen, Songlin; Zhang, Pei; Lian, Jinmin; Hu, Qiaomu; Sun, Bing; Jin, Lijun; Liu, Shanshan; Wang, Zongji; Zhao, Hongmei; Jin, Zonghui; Liang, Zhuo; Li, Yangzhen; Zheng, Qiumei; Zhang, Yong; Wang, Jun; Zhang, Guojie

2014-04-01

Environmental sex determination (ESD) occurs in divergent, phylogenetically unrelated taxa, and in some species, co-occurs with genetic sex determination (GSD) mechanisms. Although epigenetic regulation in response to environmental effects has long been proposed to be associated with ESD, a systemic analysis on epigenetic regulation of ESD is still lacking. Using half-smooth tongue sole (Cynoglossus semilaevis) as a model-a marine fish that has both ZW chromosomal GSD and temperature-dependent ESD-we investigated the role of DNA methylation in transition from GSD to ESD. Comparative analysis of the gonadal DNA methylomes of pseudomale, female, and normal male fish revealed that genes in the sex determination pathways are the major targets of substantial methylation modification during sexual reversal. Methylation modification in pseudomales is globally inherited in their ZW offspring, which can naturally develop into pseudomales without temperature incubation. Transcriptome analysis revealed that dosage compensation occurs in a restricted, methylated cytosine enriched Z chromosomal region in pseudomale testes, achieving equal expression level in normal male testes. In contrast, female-specific W chromosomal genes are suppressed in pseudomales by methylation regulation. We conclude that epigenetic regulation plays multiple crucial roles in sexual reversal of tongue sole fish. We also offer the first clues on the mechanisms behind gene dosage balancing in an organism that undergoes sexual reversal. Finally, we suggest a causal link between the bias sex chromosome assortment in the offspring of a pseudomale family and the transgenerational epigenetic inheritance of sexual reversal in tongue sole fish.

THE GENETIC STRUCTURE OF DIFFERENT AGE GROUPS OF SILVER (HYPOPHTHALMICHTHYS MOLITRIX) AND BIGHEAD (ARISTICHTHYS NOBILIS) CARPS FROM FISH FARM LIMANSKE

OpenAIRE

Т. Nagorniuk; I. Hrytsyniak; N. Borysenko

2015-01-01

Purpose. Studying the peculiarities of the genetic structure of different age groups of silver and bighead carps from fish farm Limanske with the use of genetic-biochemical markers. Methodology. The methods of vertical polyacrylamide and horizontal starch electrophoresis with our own modifications have been used for the study. Sampling of the biological material and histochemical staining of gel plates were carried out using the generally accepted methods. Statistical analysis of the obta...

Dendrite and spine modifications in autism and related neurodevelopmental disorders in patients and animal models.

Science.gov (United States)

Martínez-Cerdeño, Verónica

2017-04-01

Dendrites and spines are the main neuronal structures receiving input from other neurons and glial cells. Dendritic and spine number, size, and morphology are some of the crucial factors determining how signals coming from individual synapses are integrated. Much remains to be understood about the characteristics of neuronal dendrites and dendritic spines in autism and related disorders. Although there have been many studies conducted using autism mouse models, few have been carried out using postmortem human tissue from patients. Available animal models of autism include those generated through genetic modifications and those non-genetic models of the disease. Here, we review how dendrite and spine morphology and number is affected in autism and related neurodevelopmental diseases, both in human, and genetic and non-genetic animal models of autism. Overall, data obtained from human and animal models point to a generalized reduction in the size and number, as well as an alteration of the morphology of dendrites; and an increase in spine densities with immature morphology, indicating a general spine immaturity state in autism. Additional human studies on dendrite and spine number and morphology in postmortem tissue are needed to understand the properties of these structures in the cerebral cortex of patients with autism. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 419-437, 2017. © 2016 Wiley Periodicals, Inc.

Evolutionary model with genetics, aging, and knowledge

Science.gov (United States)

Bustillos, Armando Ticona; de Oliveira, Paulo Murilo

2004-02-01

We represent a process of learning by using bit strings, where 1 bits represent the knowledge acquired by individuals. Two ways of learning are considered: individual learning by trial and error, and social learning by copying knowledge from other individuals or from parents in the case of species with parental care. The age-structured bit string allows us to study how knowledge is accumulated during life and its influence over the genetic pool of a population after many generations. We use the Penna model to represent the genetic inheritance of each individual. In order to study how the accumulated knowledge influences the survival process, we include it to help individuals to avoid the various death situations. Modifications in the Verhulst factor do not show any special feature due to its random nature. However, by adding years to life as a function of the accumulated knowledge, we observe an improvement of the survival rates while the genetic fitness of the population becomes worse. In this latter case, knowledge becomes more important in the last years of life where individuals are threatened by diseases. Effects of offspring overprotection and differences between individual and social learning can also be observed. Sexual selection as a function of knowledge shows some effects when fidelity is imposed.

Merging data from genetic and epigenetic approaches to better understand autistic spectrum disorder.

Science.gov (United States)

Grayson, Dennis R; Guidotti, Alessandro

2016-01-01

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that is characterized by a wide range of cognitive and behavioral abnormalities. Genetic research has identified large numbers of genes that contribute to ASD phenotypes. There is compelling evidence that environmental factors contribute to ASD through influences that differentially impact the brain through epigenetic mechanisms. Both genetic mutations and epigenetic influences alter gene expression in different cell types of the brain. Mutations impact the expression of large numbers of genes and also have downstream consequences depending on specific pathways associated with the mutation. Environmental factors impact the expression of sets of genes by altering methylation/hydroxymethylation patterns, local histone modification patterns and chromatin remodeling. Herein, we discuss recent developments in the research of ASD with a focus on epigenetic pathways as a complement to current genetic screening.

WONOEP appraisal: new genetic approaches to study epilepsy

Science.gov (United States)

Rossignol, Elsa; Kobow, Katja; Simonato, Michele; Loeb, Jeffrey A.; Grisar, Thierry; Gilby, Krista L.; Vinet, Jonathan; Kadam, Shilpa D.; Becker, Albert J.

2014-01-01

Objective New genetic investigation techniques, including next-generation sequencing, epigenetic profiling, cell lineage mapping, targeted genetic manipulation of specific neuronal cell types, stem cell reprogramming and optogenetic manipulations within epileptic networks are progressively unravelling the mysteries of epileptogenesis and ictogenesis. These techniques have opened new avenues to discover the molecular basis of epileptogenesis and to study the physiological impacts of mutations in epilepsy-associated genes on a multilayer level, from cells to circuits. Methods This manuscript reviews recently published applications of these new genetic technologies in the study of epilepsy, as well as work presented by the authors at the genetic session of the XII Workshop on the Neurobiology of Epilepsy in Quebec, Canada. Results Next-generation sequencing is providing investigators with an unbiased means to assess the molecular causes of sporadic forms of epilepsy and have revealed the complexity and genetic heterogeneity of sporadic epilepsy disorders. To assess the functional impact of mutations in these newly identified genes on specific neuronal cell-types during brain development, new modeling strategies in animals, including conditional genetics in mice and in utero knockdown approaches, are enabling functional validation with exquisite cell-type and temporal specificity. In addition, optogenetics, using cell-type specific Cre recombinase driver lines, is enabling investigators to dissect networks involved in epilepsy. Genetically-encoded cell-type labeling is also providing new means to assess the role of the non-neuronal components of epileptic networks such as glial cells. Furthermore, beyond its role in revealing coding variants involved in epileptogenesis, next-generation sequencing can be used to assess the epigenetic modifications that lead to sustained network hyperexcitability in epilepsy, including methylation changes in gene promoters and non

From Precaution to Peril: Public Relations Across Forty Years of Genetic Engineering.

Science.gov (United States)

Hogan, Andrew J

2016-12-01

The Asilomar conference on genetic engineering in 1975 has long been pointed to by scientists as a model for internal regulation and public engagement. In 2015, the organizers of the International Summit on Human Gene Editing in Washington, DC looked to Asilomar as they sought to address the implications of the new CRISPR gene editing technique. Like at Asilomar, the conveners chose to limit the discussion to a narrow set of potential CRISPR applications, involving inheritable human genome editing. The adoption by scientists in 2015 of an Asilomar-like script for discussing genetic engineering offers historians the opportunity to analyze the adjustments that have been made since 1975, and to identify the blind spots that remain in public engagement. Scientists did take important lessons from the fallout of their limited engagement with public concerns at Asilomar. Nonetheless, the scientific community has continued to overlook some of the longstanding public concerns about genetic engineering, in particular the broad and often covert genetic modification of food products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Acceptance of a food of animal origin obtained through genetic modification and cloning in South America

DEFF Research Database (Denmark)

Schnettler, Berta; Velásquez, Carlos; Miranda, Horacio

2015-01-01

With the aim of comparing the acceptance of milk obtained from cloned, genetically modified (GM) and conventionally bred cows among working adults and university students, and identifying and characterizing typologies among both subsamples in terms of their preferences, a survey was applied to 40...

Genetic interaction analysis of point mutations enables interrogation of gene function at a residue-level resolution

Science.gov (United States)

Braberg, Hannes; Moehle, Erica A.; Shales, Michael; Guthrie, Christine; Krogan, Nevan J.

2014-01-01

We have achieved a residue-level resolution of genetic interaction mapping – a technique that measures how the function of one gene is affected by the alteration of a second gene – by analyzing point mutations. Here, we describe how to interpret point mutant genetic interactions, and outline key applications for the approach, including interrogation of protein interaction interfaces and active sites, and examination of post-translational modifications. Genetic interaction analysis has proven effective for characterizing cellular processes; however, to date, systematic high-throughput genetic interaction screens have relied on gene deletions or knockdowns, which limits the resolution of gene function analysis and poses problems for multifunctional genes. Our point mutant approach addresses these issues, and further provides a tool for in vivo structure-function analysis that complements traditional biophysical methods. We also discuss the potential for genetic interaction mapping of point mutations in human cells and its application to personalized medicine. PMID:24842270

Whole-genome gene expression modifications associated with nitrosamine exposure and micronucleus frequency in human blood cells

DEFF Research Database (Denmark)

Hebels, Dennie G A J; Jennen, Danyel G J; van Herwijnen, Marcel H M

2011-01-01

association between MN frequency and urinary NOCs (r = 0.41, P = 0.025) and identified modifications in among others cytoskeleton remodeling, cell cycle, apoptosis and survival, signal transduction, immune response, G-protein signaling and development pathways, which indicate a response to NOC......-induced genotoxicity. Moreover, we established a network of genes, the most important ones of which include FBXW7, BUB3, Caspase 2, Caspase 8, SMAD3, Huntingtin and MGMT, which are involved in processes relevant in carcinogenesis. The modified genetic processes and genes found in this study may be of interest...

Epigenetic Modifications and Diabetic Retinopathy

Directory of Open Access Journals (Sweden)

Renu A. Kowluru

2013-01-01

Full Text Available Diabetic retinopathy remains one of the most debilitating chronic complications, but despite extensive research in the field, the exact mechanism(s responsible for how retina is damaged in diabetes remains ambiguous. Many metabolic pathways have been implicated in its development, and genes associated with these pathways are altered. Diabetic environment also facilitates epigenetics modifications, which can alter the gene expression without permanent changes in DNA sequence. The role of epigenetics in diabetic retinopathy is now an emerging area, and recent work has shown that genes encoding mitochondrial superoxide dismutase (Sod2 and matrix metalloproteinase-9 (MMP-9 are epigenetically modified, activates of epigenetic modification enzymes, histone lysine demethylase 1 (LSD1, and DNA methyltransferase are increased, and the micro RNAs responsible for regulating nuclear transcriptional factor and VEGF are upregulated. With the growing evidence of epigenetic modifications in diabetic retinopathy, better understanding of these modifications has potential to identify novel targets to inhibit this devastating disease. Fortunately, the inhibitors and mimics targeted towards histone modification, DNA methylation, and miRNAs are now being tried for cancer and other chronic diseases, and better understanding of the role of epigenetics in diabetic retinopathy will open the door for their possible use in combating this blinding disease.

Y-chromosome variation in Altaian Kazakhs reveals a common paternal gene pool for Kazakhs and the influence of Mongolian expansions.

Science.gov (United States)

Dulik, Matthew C; Osipova, Ludmila P; Schurr, Theodore G

2011-03-11

Kazakh populations have traditionally lived as nomadic pastoralists that seasonally migrate across the steppe and surrounding mountain ranges in Kazakhstan and southern Siberia. To clarify their population history from a paternal perspective, we analyzed the non-recombining portion of the Y-chromosome from Kazakh populations living in southern Altai Republic, Russia, using a high-resolution analysis of 60 biallelic markers and 17 STRs. We noted distinct differences in the patterns of genetic variation between maternal and paternal genetic systems in the Altaian Kazakhs. While they possess a variety of East and West Eurasian mtDNA haplogroups, only three East Eurasian paternal haplogroups appear at significant frequencies (C3*, C3c and O3a3c*). In addition, the Y-STR data revealed low genetic diversity within these lineages. Analysis of the combined biallelic and STR data also demonstrated genetic differences among Kazakh populations from across Central Asia. The observed differences between Altaian Kazakhs and indigenous Kazakhs were not the result of admixture between Altaian Kazakhs and indigenous Altaians. Overall, the shared paternal ancestry of Kazakhs differentiates them from other Central Asian populations. In addition, all of them showed evidence of genetic influence by the 13(th) century CE Mongol Empire. Ultimately, the social and cultural traditions of the Kazakhs shaped their current pattern of genetic variation.

Y-chromosome variation in Altaian Kazakhs reveals a common paternal gene pool for Kazakhs and the influence of Mongolian expansions.

Directory of Open Access Journals (Sweden)

Matthew C Dulik

Full Text Available Kazakh populations have traditionally lived as nomadic pastoralists that seasonally migrate across the steppe and surrounding mountain ranges in Kazakhstan and southern Siberia. To clarify their population history from a paternal perspective, we analyzed the non-recombining portion of the Y-chromosome from Kazakh populations living in southern Altai Republic, Russia, using a high-resolution analysis of 60 biallelic markers and 17 STRs. We noted distinct differences in the patterns of genetic variation between maternal and paternal genetic systems in the Altaian Kazakhs. While they possess a variety of East and West Eurasian mtDNA haplogroups, only three East Eurasian paternal haplogroups appear at significant frequencies (C3*, C3c and O3a3c*. In addition, the Y-STR data revealed low genetic diversity within these lineages. Analysis of the combined biallelic and STR data also demonstrated genetic differences among Kazakh populations from across Central Asia. The observed differences between Altaian Kazakhs and indigenous Kazakhs were not the result of admixture between Altaian Kazakhs and indigenous Altaians. Overall, the shared paternal ancestry of Kazakhs differentiates them from other Central Asian populations. In addition, all of them showed evidence of genetic influence by the 13(th century CE Mongol Empire. Ultimately, the social and cultural traditions of the Kazakhs shaped their current pattern of genetic variation.

An integrated epigenetic and genetic analysis of DNA methyltransferase genes (DNMTs) in tumor resistant and susceptible chicken lines

Science.gov (United States)

Both epigenetic alterations and genetic variations play essential roles in tumorigenesis. The epigenetic modification of DNA methylation is catalyzed and maintained by the DNA methyltransferases (DNMT3a, DNMT3b and DNMT1). DNA mutations and DNA methylation profiles of DNMTs themselves and their rela...

DNA extraction methods for detecting genetically modified foods: A comparative study.

Science.gov (United States)

Elsanhoty, Rafaat M; Ramadan, Mohamed Fawzy; Jany, Klaus Dieter

2011-06-15

The work presented in this manuscript was achieved to compare six different methods for extracting DNA from raw maize and its derived products. The methods that gave higher yield and quality of DNA were chosen to detect the genetic modification in the samples collected from the Egyptian market. The different methods used were evaluated for extracting DNA from maize kernels (without treatment), maize flour (mechanical treatment), canned maize (sweet corn), frozen maize (sweet corn), maize starch, extruded maize, popcorn, corn flacks, maize snacks, and bread made from corn flour (mechanical and thermal treatments). The quality and quantity of the DNA extracted from the standards, containing known percentages of GMO material and from the different food products were evaluated. For qualitative detection of the GMO varieties in foods, the GMOScreen 35S/NOS test kit was used, to screen the genetic modification in the samples. The positive samples for the 35S promoter and/or the NOS terminator were identified by the standard methods adopted by EU. All of the used methods extracted yielded good DNA quality. However, we noted that the purest DNA extract were obtained using the DNA extraction kit (Roche) and this generally was the best method for extracting DNA from most of the maize-derived foods. We have noted that the yield of DNA extracted from maize-derived foods was generally lower in the processed products. The results indicated that 17 samples were positive for the presence of 35S promoter, while 34% from the samples were positive for the genetically modified maize line Bt-176. Copyright © 2010 Elsevier Ltd. All rights reserved.

Fatty acid modification of Wnt1 and Wnt3a at serine is prerequisite for lipidation at cysteine and is essential for Wnt signalling

Czech Academy of Sciences Publication Activity Database

Doubravská, Lenka; Krausová, Michaela; Gradl, D.; Vojtěchová, Martina; Tůmová, Lucie; Lukáš, Jan; Valenta, Tomáš; Pospíchalová, Vendula; Fafílek, Bohumil; Plachý, Jiří; Sebesta, O.; Kořínek, Vladimír

2011-01-01

Roč. 23, č. 5 (2011), s. 837-848 ISSN 0898-6568 R&D Projects: GA ČR(CZ) GA204/07/1567; GA MŠk 1M0506 Institutional research plan: CEZ:AV0Z50520514 Keywords : Wnt signaling * post-translational modification * acylation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.058, year: 2011

Risk assessment: the importance of genetic polymorphisms in man

DEFF Research Database (Denmark)

Knudsen, Lisbeth E.; Loft, S H; Autrup, H

2001-01-01

and increased cancer risk, such results indicate effect modification regarding cancer risk. In risk assessment the safety 'factor' of 10 is generally accepted to allow for variation in individual susceptibility. Reviewing the literature justifies the factor of 10 when considering single polymorphisms. However......Many genetic polymorphisms in metabolism enzymes are important for the risk of cancer as shown in a large number of case-control studies. The relative risk estimates have shown large variations between such population studies. However, in most studies the relative risk estimates are in the range...

Genetic Techniques for Manipulation of the Phytosterol Biotransformation Strain Mycobacterium neoaurum NRRL B-3805.

Science.gov (United States)

Loraine, Jessica K; Smith, Margaret C M

2017-01-01

Mycobacterium neoaurum is a saprophytic, soil-dwelling bacterium. The strain NRRL B-3805 converts phytosterols to androst-4-ene-3,17-dione (androstenedione; AD), a precursor of multiple C19 steroids of importance to industry. NRRL B-3805 itself is able to convert AD to other steroid products, including testosterone (Ts) and androst-1,4-diene-3,17-dione (androstadienedione; ADD). However to improve this strain for industrial use, genetic modification is a priority. In this chapter, we describe a range of genetic techniques that can be used for M. neoaurum NRRL B-3805. Methods for transformation, expression, and gene knockouts are presented as well as plasmid maintenance and stability.

Use of a Yeast tRNase Killer Toxin to Diagnose Kti12 Motifs Required for tRNA Modification by Elongator.

Science.gov (United States)

Mehlgarten, Constance; Prochaska, Heike; Hammermeister, Alexander; Abdel-Fattah, Wael; Wagner, Melanie; Krutyhołowa, Rościsław; Jun, Sang Eun; Kim, Gyung-Tae; Glatt, Sebastian; Breunig, Karin D; Stark, Michael J R; Schaffrath, Raffael

2017-09-05

Saccharomyces cerevisiae cells are killed by zymocin, a tRNase ribotoxin complex from Kluyveromyces lactis , which cleaves anticodons and inhibits protein synthesis. Zymocin's action requires specific chemical modification of uridine bases in the anticodon wobble position (U34) by the Elongator complex (Elp1-Elp6). Hence, loss of anticodon modification in mutants lacking Elongator or related KTI ( K. lactis Toxin Insensitive) genes protects against tRNA cleavage and confers resistance to the toxin. Here, we show that zymocin can be used as a tool to genetically analyse KTI12 , a gene previously shown to code for an Elongator partner protein. From a kti12 mutant pool of zymocin survivors, we identify motifs in Kti12 that are functionally directly coupled to Elongator activity. In addition, shared requirement of U34 modifications for nonsense and missense tRNA suppression ( SUP4 ; SOE1 ) strongly suggests that Kti12 and Elongator cooperate to assure proper tRNA functioning. We show that the Kti12 motifs are conserved in plant ortholog DRL1/ELO4 from Arabidopsis thaliana and seem to be involved in binding of cofactors (e.g., nucleotides, calmodulin). Elongator interaction defects triggered by mutations in these motifs correlate with phenotypes typical for loss of U34 modification. Thus, tRNA modification by Elongator appears to require physical contact with Kti12, and our preliminary data suggest that metabolic signals may affect proper communication between them.

Proteomic analysis of post-translational modifications

DEFF Research Database (Denmark)

Mann, Matthias; Jensen, Ole N

2003-01-01

Post-translational modifications modulate the activity of most eukaryote proteins. Analysis of these modifications presents formidable challenges but their determination generates indispensable insight into biological function. Strategies developed to characterize individual proteins are now...... systematically applied to protein populations. The combination of function- or structure-based purification of modified 'subproteomes', such as phosphorylated proteins or modified membrane proteins, with mass spectrometry is proving particularly successful. To map modification sites in molecular detail, novel...

Chemical Modifications of Starch: Microwave Effect

OpenAIRE

Lewicka, Kamila; Siemion, Przemysław; Kurcok, Piotr

2015-01-01

This paper presents basic methods of starch chemical modification, the effect of microwave radiation on the modification process, and the physicochemical properties of starch. It has been shown that the modifications contribute to improvement of the material performance and likewise to significant improvement of its mechanical properties. As a result, more and more extensive use of starch is possible in various industries. In addition, methods of oxidized starch and starch esters preparation ...

The surface modification of polystyrene

International Nuclear Information System (INIS)

Tremlett, C.

2000-03-01

Polymers have ideal bulk properties for many applications. However, adhesion to many polymers is poor without surface pretreatment. This can result, for example, in peeling paint and printing, adhesive joint failure and bio-incompatibility. In applications such as painting, printing, adhesive bonding and biocompatibility, various cleaning or surface chemical modifications may be employed. A commodity polymer where pretreatment is sometimes needed is polystyrene. This project investigated, in detail, the effects of a novel method of modification namely mediated electrochemical oxidation (MEO), as a mode of surface modification on polystyrene and a comparison was made with other polymers. The resulting modification was investigated using a range of surface analysis techniques to obtain complementary information. These included, X-ray photoelectron spectroscopy, contact angles, static secondary ion mass spectrometry, atomic force microscopy, chemical derivatization, scanning electron microscopy, attenuated total reflection Fourier Transform infrared spectroscopy and composite lap shear joint testing. It has been shown that MEO modifies the surface of polystyrene introduced oxygen mainly as hydroxyl groups, and a small number of carbonyl groups, that are positioned only on the backbone hydrocarbon chain. This modification improved adhesion, was stable and samples could be stored in aqueous media. The resulting hydroxylation was further derivatized using an amino acid to provide a specialised surface. This was very different from the multiple oxygen functionalities introduced in the comparison studies by UV/ozone and plasma treatments. (author)

Characterization of the E.coli proteome and its modifications during growth and ethanol stress

Directory of Open Access Journals (Sweden)

Boumediene eSoufi

2015-02-01

Full Text Available We set out to provide a resource to the microbiology community especially with respect to systems biology based endeavors. To this end, we generated a comprehensive dataset monitoring the changes in protein expression, copy number, and post translational modifications in a systematic fashion during growth and ethanol stress in E.coli. We utilized high-resolution mass spectrometry combined with the Super-SILAC approach. In a single experiment, we have identified over 2,300 proteins, which represent approximately 88% of the estimated expressed proteome of E. coli and estimated protein copy numbers using the Intensity Based Absolute Quantitation (IBAQ. The dynamic range of protein expression spanned up to six orders of magnitude, with the highest protein copy per cell estimated at approximately 300,000. We focused on the proteome dynamics involved during stationary phase growth. A global up-regulation of proteins related to stress response was detected in later stages of growth. We observed the down-regulation of the methyl directed mismatch repair system containing MutS and MutL of E. coli growing in long term growth cultures, confirming that higher incidence of mutations presents an important mechanism in the increase in genetic diversity and stationary phase survival in E.coli. During ethanol stress, known markers such as alcohol dehydrogenase and aldehyde dehydrogenase were induced, further validating the dataset. Finally, we performed unbiased protein modification detection and revealed changes of many known and unknown protein modifications in both experimental conditions.

Application of radiation technology in starch modification

International Nuclear Information System (INIS)

Chen Huiyuan; Peng Zhigang; Ding Zhongmin; Lu Jiajiu

2007-01-01

In order to commercialize the radiation modification of starch, corn starch was irradiated with different dose of 60 Co gamma radiations. Some basic physical and chemical properties of the resulted modified starch paste were measured with emphasis on the viscosity stability and tensile strength. The results indicate that irradiation of corn starch with a dose of 4-10 kGy can decrease its viscosity to 5-14 mPa·s, and the tensile strength can meet the standard set up for textile paste. In comparison with chemical modification for starch, radiation modification is simpler in technology, more convenient in operation, more stable in modification quality, and easier to control. The mechanism of radiation modification of starch was also discussed. (authors)

Assessment of genetically modified soybean crops and different cultivars by Fourier transform infrared spectroscopy and chemometric analysis

Directory of Open Access Journals (Sweden)

Glaucia Braz Alcantara

2010-06-01

Full Text Available This paper describes the potentiality of Fourier transform infrared (FT-IR spectroscopy associated to chemometric analysis for assessment of conventional and genetically modified soybean crops. Recently, genetically modified organisms have been queried about their influence on the environment and their safety as food/feed. In this regard, chemical investigations are ever more required. Thus three different soybean cultivars distributed in transgenic Roundup ReadyTM soybean and theirs conventional counterparts were directly investigated by FT-IR spectroscopy and chemometric analysis. The application of PCA and KNN methods permitted the discrimination and classification of the genetically modified samples from conventional ones when they were separately analysed. The analyses showed the chemical variation according to genetic modification. Furthermore, this methodology was efficient for cultivar grouping and highlights cultivar dependence for discrimination between transgenic and non-transgenic samples. According to this study, FT-IR and chemometrics could be used as a quick, easy and low cost tool to assess the chemical composition variation in genetically modified organisms.

A symbiotic liaison between the genetic and epigenetic code

Directory of Open Access Journals (Sweden)

Holger eHeyn

2014-05-01

Full Text Available With rapid advances in sequencing technologies, we are undergoing a paradigm shift from hypothesis- to data-driven research. Genome-wide profiling efforts gave informative insights into biological processes; however, considering the wealth of variation, the major challenge remains their meaningful interpretation. In particular sequence variation in non-coding contexts is often challenging to interpret. Here, data integration approaches for the identification of functional genetic variability represent a likely solution. Exemplary, functional linkage analysis integrating genotype and expression data determined regulatory quantitative trait loci (QTL and proposed causal relationships. In addition to gene expression, epigenetic regulation and specifically DNA methylation was established as highly valuable surrogate mark for functional variance of the genetic code. Epigenetic modification served as powerful mediator trait to elucidate mechanisms forming phenotypes in health and disease. Particularly, integrative studies of genetic and DNA methylation data yet guided interpretation strategies of risk genotypes, but also proved their value for physiological traits, such as natural human variation and aging. This Perspective seeks to illustrate the power of data integration in the genomic era exemplified by DNA methylation quantitative trait loci (meQTLs. However, the model is further extendable to virtually all traceable molecular traits.

Emerging technologies to create inducible and genetically defined porcine cancer models

Directory of Open Access Journals (Sweden)

Lawrence B Schook

2016-02-01

Full Text Available There is an emerging need for new animal models that address unmet translational cancer research requirements. Transgenic porcine models provide an exceptional opportunity due to their genetic, anatomic and physiological similarities with humans. Due to recent advances in the sequencing of domestic animal genomes and the development of new organism cloning technologies, it is now very feasible to utilize pigs as a malleable species, with similar anatomic and physiological features with humans, in which to develop cancer models. In this review, we discuss genetic modification technologies successfully used to produce porcine biomedical models, in particular the Cre-loxP System as well as major advances and perspectives the CRISPR/Cas9 System. Recent advancements in porcine tumor modeling and genome editing will bring porcine models to the forefront of translational cancer research.

Emerging Technologies to Create Inducible and Genetically Defined Porcine Cancer Models.

Science.gov (United States)

Schook, Lawrence B; Rund, Laurie; Begnini, Karine R; Remião, Mariana H; Seixas, Fabiana K; Collares, Tiago

2016-01-01

There is an emerging need for new animal models that address unmet translational cancer research requirements. Transgenic porcine models provide an exceptional opportunity due to their genetic, anatomic, and physiological similarities with humans. Due to recent advances in the sequencing of domestic animal genomes and the development of new organism cloning technologies, it is now very feasible to utilize pigs as a malleable species, with similar anatomic and physiological features with humans, in which to develop cancer models. In this review, we discuss genetic modification technologies successfully used to produce porcine biomedical models, in particular the Cre-loxP System as well as major advances and perspectives the CRISPR/Cas9 System. Recent advancements in porcine tumor modeling and genome editing will bring porcine models to the forefront of translational cancer research.

New Genetic Insights from Autoimmune Thyroid Disease

Directory of Open Access Journals (Sweden)

Terry F. Davies

2012-01-01

Full Text Available The autoimmune thyroid diseases (AITDs (Graves’ disease and Hashimoto’s thyroiditis are complex genetic diseases which most likely have more than 20 genes contributing to the clinical phenotypes. To date, the genes known to be contributing fall into two categories: immune regulatory genes (including HLA, CTLA4, PTPN22, CD40, CD25, and FCRL3 and thyroid-specific genes (TG and TSHR. However, none of these genes contribute more than a 4-fold increase in risk of developing one of these diseases, and none of the polymorphisms discovered is essential for disease development. Hence, it appears that a variety of different gene interactions can combine to cause the same clinical disease pattern, but the contributing genes may differ from patient to patient and from population to population. Furthermore, this possible mechanism leaves open the powerful influence of the environment and epigenetic modifications of gene expression. For the clinician, this means that genetic profiling of such patients is unlikely to be fruitful in the near future.

Pragmatic Graph Rewriting Modifications

OpenAIRE

Rodgers, Peter; Vidal, Natalia

1999-01-01

We present new pragmatic constructs for easing programming in visual graph rewriting programming languages. The first is a modification to the rewriting process for nodes the host graph, where nodes specified as 'Once Only' in the LHS of a rewrite match at most once with a corresponding node in the host graph. This reduces the previously common use of tags to indicate the progress of matching in the graph. The second modification controls the application of LHS graphs, where those specified a...

Methodological guidelines for developing accident modification functions

DEFF Research Database (Denmark)

Elvik, Rune

2015-01-01

This paper proposes methodological guidelines for developing accident modification functions. An accident modification function is a mathematical function describing systematic variation in the effects of road safety measures. The paper describes ten guidelines. An example is given of how to use...... limitations in developing accident modification functions are the small number of good evaluation studies and the often huge variation in estimates of effect. It is therefore still not possible to develop accident modification functions for very many road safety measures. © 2015 Elsevier Ltd. All rights...... the guidelines. The importance of exploratory analysis and an iterative approach in developing accident modification functions is stressed. The example shows that strict compliance with all the guidelines may be difficult, but represents a level of stringency that should be strived for. Currently the main...

Identification of a herpes simplex labialis susceptibility region on human chromosome 21.

Science.gov (United States)

Hobbs, Maurine R; Jones, Brandt B; Otterud, Brith E; Leppert, Mark; Kriesel, John D

2008-02-01

Most of the United States population is infected with either herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2, or both. Reactivations of HSV-1 infection cause herpes simplex labialis (HSL; cold sores or fever blisters), which is the most common recurring viral infection in humans. To investigate the possibility of a human genetic component conferring resistance or susceptibility to cold sores (i.e., a HSL susceptibility gene), we conducted a genetic linkage analysis that included serotyping and phenotyping 421 individuals from 39 families enrolled in the Utah Genetic Reference Project. Linkage analysis identified a 2.5-Mb nonrecombinant region of interest on the long arm of human chromosome 21, with a multipoint logarithm of odds score of 3.9 noted near marker abmc65 (D21S409). Nonparametric linkage analysis of the data also provided strong evidence for linkage (P = .0005). This region of human chromosome 21 contains 6 candidate genes for herpes susceptibility. The development of frequent cold sores is associated with a region on the long arm of human chromosome 21. This region contains several candidate genes that could influence the frequency of outbreaks of HSL.

The genetic signature of sex-biased migration in patrilocal chimpanzees and humans.

Directory of Open Access Journals (Sweden)

Kevin E Langergraber

Full Text Available A large body of theoretical work suggests that analyses of variation at the maternally inherited mitochondrial (mtDNA and the paternally inherited non-recombining portion of the Y chromosome (NRY are a potentially powerful way to reveal the differing migratory histories of men and women across human societies. However, the few empirical studies comparing mtDNA and NRY variation and known patterns of sex-biased migration have produced conflicting results. Here we review some methodological reasons for these inconsistencies, and take them into account to provide an unbiased characterization of mtDNA and NRY variation in chimpanzees, one of the few mammalian taxa where males routinely remain in and females typically disperse from their natal groups. We show that patterns of mtDNA and NRY variation are more strongly contrasting in patrilocal chimpanzees compared with patrilocal human societies. The chimpanzee data we present here thus provide a valuable comparative benchmark of the patterns of mtDNA and NRY variation to be expected in a society with extremely female-biased dispersal.

Mixtures of genetically modified wheat lines outperform monocultures.

Science.gov (United States)

Zeller, Simon L; Kalinina, Olena; Flynn, Dan F B; Schmid, Bernhard

2012-09-01

Biodiversity research shows that diverse plant communities are more stable and productive than monocultures. Similarly, populations in which genotypes with different pathogen resistance are mixed may have lower pathogen levels and thus higher productivity than genetically uniform populations. We used genetically modified (GM) wheat as a model system to test this prediction, because it allowed us to use genotypes that differed only in the trait pathogen resistance but were otherwise identical. We grew three such genotypes or lines in monocultures or two-line mixtures. Phenotypic measurements were taken at the level of individual plants and of entire plots (population level). We found that resistance to mildew increased with both GM richness (0, 1, or 2 Pm3 transgenes with different resistance specificities per plot) and GM concentration (0%, 50%, or 100% of all plants in a plot with a Pm3 transgene). Plots with two transgenes had 34.6% less mildew infection and as a consequence 7.3% higher seed yield than plots with one transgene. We conclude that combining genetic modification with mixed cropping techniques could be a promising approach to increase sustainability and productivity in agricultural systems, as the fitness cost of stacking transgenes within individuals may thus be avoided.

Empirical study of self-configuring genetic programming algorithm performance and behaviour

International Nuclear Information System (INIS)

KrasnoyarskiyRabochiy prospect, Krasnoyarsk, 660014 (Russian Federation))" data-affiliation=" (Siberian State Aerospace University named after Academician M.F. Reshetnev 31 KrasnoyarskiyRabochiy prospect, Krasnoyarsk, 660014 (Russian Federation))" >Semenkin, E; KrasnoyarskiyRabochiy prospect, Krasnoyarsk, 660014 (Russian Federation))" data-affiliation=" (Siberian State Aerospace University named after Academician M.F. Reshetnev 31 KrasnoyarskiyRabochiy prospect, Krasnoyarsk, 660014 (Russian Federation))" >Semenkina, M

2015-01-01

The behaviour of the self-configuring genetic programming algorithm with a modified uniform crossover operator that implements a selective pressure on the recombination stage, is studied over symbolic programming problems. The operator's probabilistic rates interplay is studied and the role of operator variants on algorithm performance is investigated. Algorithm modifications based on the results of investigations are suggested. The performance improvement of the algorithm is demonstrated by the comparative analysis of suggested algorithms on the benchmark and real world problems

GENETIC CONTRIBUTION OF RAM ON LITTER SIZE IN ŠUMAVA SHEEP

Directory of Open Access Journals (Sweden)

Jitka Schmidová

2015-09-01

Full Text Available The objective of the present study was to quantify the service sire effect in terms of (co variance components of born and weaned lambs number and to propose models for the potential inclusion of this effect in the linear equations for breeding value estimation. The database with 21,324 lambings in Šumava sheep from 1992- 2013 was used. The basic model equation for the analysis of variance of litter size contained effects of ewe´s age at lambing, contemporary group, permanent environmental effect of ewe and direct additive genetic effect of ewe. Two modifications of the basic model were used for estimation of service sire effect. The proportions of variance for the service sire effect for number of born and weaned lambs were 2.1% and 2.0%, when service sire was not included into relationship matrix; while included into the relationship matrix and dividing effect into genetic contribution and permanent environment effect refer that nongenetic effect seems to be bigger than genetic (0.013 vs. 0.009 for number of born and 0.017 vs. 0.004 for number of weaned. Changes in other variance components were relatively low, except of contemporary group. Model including service sire effect as a simple random effect without genetic relationship matrix inclusion is recommended for genetic evaluation of litter size traits.

Genetically encoded lipid-polypeptide hybrid biomaterials that exhibit temperature-triggered hierarchical self-assembly

Science.gov (United States)

Mozhdehi, Davoud; Luginbuhl, Kelli M.; Simon, Joseph R.; Dzuricky, Michael; Berger, Rüdiger; Varol, H. Samet; Huang, Fred C.; Buehne, Kristen L.; Mayne, Nicholas R.; Weitzhandler, Isaac; Bonn, Mischa; Parekh, Sapun H.; Chilkoti, Ashutosh

2018-05-01

Post-translational modification of proteins is a strategy widely used in biological systems. It expands the diversity of the proteome and allows for tailoring of both the function and localization of proteins within cells as well as the material properties of structural proteins and matrices. Despite their ubiquity in biology, with a few exceptions, the potential of post-translational modifications in biomaterials synthesis has remained largely untapped. As a proof of concept to demonstrate the feasibility of creating a genetically encoded biohybrid material through post-translational modification, we report here the generation of a family of three stimulus-responsive hybrid materials—fatty-acid-modified elastin-like polypeptides—using a one-pot recombinant expression and post-translational lipidation methodology. These hybrid biomaterials contain an amphiphilic domain, composed of a β-sheet-forming peptide that is post-translationally functionalized with a C14 alkyl chain, fused to a thermally responsive elastin-like polypeptide. They exhibit temperature-triggered hierarchical self-assembly across multiple length scales with varied structure and material properties that can be controlled at the sequence level.

Ethics of genetic testing and research in sport: a position statement from the Australian Institute of Sport

Science.gov (United States)

Vlahovich, Nicole; Fricker, Peter A; Brown, Matthew A; Hughes, David

2017-01-01

As Australia's peak high-performance sport agency, the Australian Institute of Sport (AIS) has developed this position statement to address the implications of recent advances in the field of genetics and the ramifications for the health and well-being of athletes. Genetic testing has proven of value in the practice of clinical medicine. There are, however, currently no scientific grounds for the use of genetic testing for athletic performance improvement, sport selection or talent identification. Athletes and coaches should be discouraged from using direct-to-consumer genetic testing because of its lack of validation and replicability and the lack of involvement of a medical practitioner in the process. The transfer of genetic material or genetic modification of cells for performance enhancement is gene doping and should not be used on athletes. There are, however, valid roles for genetic research and the AIS supports genetic research which aims to enhance understanding of athlete susceptibility to injury or illness. Genetic research is only to be conducted after careful consideration of a range of ethical concerns which include the provision of adequate informed consent. The AIS is committed to providing leadership in delivering an ethical framework that protects the well-being of athletes and the integrity of sport, in the rapidly changing world of genomic science. PMID:27899345

Bioethanol production using genetically modified and mutant wheat and barley straws

Energy Technology Data Exchange (ETDEWEB)

Li, Z. [Washington State Univ., Pullman, WA (US). Dept. of Biological Engineering; East China Univ. of Science and Technology, Shanghai (CN). State Key Laboratory of Bioreactor Engineering; Liu, Y. [Michigan State Univ., East Lansing, MI (US). Biosystems and Agricultural Engineering; Chen, S. [Washington State Univ., Pullman, WA (US). Dept. of Biological Systems Engineering; Zemetra, R.S. [Univ. of Idaho, Moscow, ID (US). Plant, Soil, and Entomological Sciences

2011-01-15

To improve the performance of wheat and barley straws as feedstocks for ethanol biorefining, the genetic modifications of down regulating Cinnamoyl-CoA reductase and low phytic acid mutation have been introduced into wheat and barley respectively. In this study, total 252 straw samples with different genetic background and location were collected from the field experiment based on a randomized complete block design. The fiber analysis (neutral detergent fiber, acid detergent fiber, and acid detergent lignin) indicated that there were no significant differences between modified and wild type straw lines in terms of straw compositions. However, the difference did exist among straw lines on fiber utilization. 16 straw samples were further selected to conduct diluted acid pretreatment, enzymatic hydrolysis and fermentation. The data indicated that the phytic acid mutant and transgenic straws have changed the fiber structure, which significantly influences their hydrolysibility. These results may lead to a possible solution of mutant or genetic modified plant species that is capable to increase the hydrolysibility of biomass without changing their compositions and sacrificing their agronomy performance. (author)

Huntingtin interacting proteins are genetic modifiers of neurodegeneration.

Directory of Open Access Journals (Sweden)

Linda S Kaltenbach

2007-05-01

Full Text Available Huntington's disease (HD is a fatal neurodegenerative condition caused by expansion of the polyglutamine tract in the huntingtin (Htt protein. Neuronal toxicity in HD is thought to be, at least in part, a consequence of protein interactions involving mutant Htt. We therefore hypothesized that genetic modifiers of HD neurodegeneration should be enriched among Htt protein interactors. To test this idea, we identified a comprehensive set of Htt interactors using two complementary approaches: high-throughput yeast two-hybrid screening and affinity pull down followed by mass spectrometry. This effort led to the identification of 234 high-confidence Htt-associated proteins, 104 of which were found with the yeast method and 130 with the pull downs. We then tested an arbitrary set of 60 genes encoding interacting proteins for their ability to behave as genetic modifiers of neurodegeneration in a Drosophila model of HD. This high-content validation assay showed that 27 of 60 orthologs tested were high-confidence genetic modifiers, as modification was observed with more than one allele. The 45% hit rate for genetic modifiers seen among the interactors is an order of magnitude higher than the 1%-4% typically observed in unbiased genetic screens. Genetic modifiers were similarly represented among proteins discovered using yeast two-hybrid and pull-down/mass spectrometry methods, supporting the notion that these complementary technologies are equally useful in identifying biologically relevant proteins. Interacting proteins confirmed as modifiers of the neurodegeneration phenotype represent a diverse array of biological functions, including synaptic transmission, cytoskeletal organization, signal transduction, and transcription. Among the modifiers were 17 loss-of-function suppressors of neurodegeneration, which can be considered potential targets for therapeutic intervention. Finally, we show that seven interacting proteins from among 11 tested were able to

The computational nature of memory modification.

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-03-15

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature.

Improvement in PWR automatic optimization reloading methods using genetic algorithm

International Nuclear Information System (INIS)

Levine, S.H.; Ivanov, K.; Feltus, M.

1996-01-01

The objective of using automatic optimized reloading methods is to provide the Nuclear Engineer with an efficient method for reloading a nuclear reactor which results in superior core configurations that minimize fuel costs. Previous methods developed by Levine et al required a large effort to develop the initial core loading using a priority loading scheme. Subsequent modifications to this core configuration were made using expert rules to produce the final core design. Improvements in this technique have been made by using a genetic algorithm to produce improved core reload designs for PWRs more efficiently (authors)

Improvement in PWR automatic optimization reloading methods using genetic algorithm

Energy Technology Data Exchange (ETDEWEB)

Levine, S H; Ivanov, K; Feltus, M [Pennsylvania State Univ., University Park, PA (United States)

1996-12-01

The objective of using automatic optimized reloading methods is to provide the Nuclear Engineer with an efficient method for reloading a nuclear reactor which results in superior core configurations that minimize fuel costs. Previous methods developed by Levine et al required a large effort to develop the initial core loading using a priority loading scheme. Subsequent modifications to this core configuration were made using expert rules to produce the final core design. Improvements in this technique have been made by using a genetic algorithm to produce improved core reload designs for PWRs more efficiently (authors).

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2004-01-01

This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2007-01-01

This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

Energy conservation potential of surface modification technologies

Energy Technology Data Exchange (ETDEWEB)

Le, H.K.; Horne, D.M.; Silberglitt, R.S.

1985-09-01

This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

Histone modifications: Cycling with chromosomal replication

DEFF Research Database (Denmark)

Thon, Genevieve

2008-01-01

Histone modifications tend to be lost during chromosome duplication. Several recent studies suggest that the RNA interference pathway becomes active during the weakened transcriptional repression occurring at centromeres in S phase, resulting in the re-establishment of histone modifications...

Histone modifications influence mediator interactions with chromatin

Science.gov (United States)

Zhu, Xuefeng; Zhang, Yongqiang; Bjornsdottir, Gudrun; Liu, Zhongle; Quan, Amy; Costanzo, Michael; Dávila López, Marcela; Westholm, Jakub Orzechowski; Ronne, Hans; Boone, Charles; Gustafsson, Claes M.; Myers, Lawrence C.

2011-01-01

The Mediator complex transmits activation signals from DNA bound transcription factors to the core transcription machinery. Genome wide localization studies have demonstrated that Mediator occupancy not only correlates with high levels of transcription, but that the complex also is present at transcriptionally silenced locations. We provide evidence that Mediator localization is guided by an interaction with histone tails, and that this interaction is regulated by their post-translational modifications. A quantitative, high-density genetic interaction map revealed links between Mediator components and factors affecting chromatin structure, especially histone deacetylases. Peptide binding assays demonstrated that pure wild-type Mediator forms stable complexes with the tails of Histone H3 and H4. These binding assays also showed Mediator—histone H4 peptide interactions are specifically inhibited by acetylation of the histone H4 lysine 16, a residue critical in transcriptional silencing. Finally, these findings were validated by tiling array analysis that revealed a broad correlation between Mediator and nucleosome occupancy in vivo, but a negative correlation between Mediator and nucleosomes acetylated at histone H4 lysine 16. Our studies show that chromatin structure and the acetylation state of histones are intimately connected to Mediator localization. PMID:21742760

Enhancement of antitumor activity of gammaretrovirus carrying IL-12 gene through genetic modification of envelope targeting HER2 receptor: a promising strategy for bladder cancer therapy.

Science.gov (United States)

Tsai, Y-S; Shiau, A-L; Chen, Y-F; Tsai, H-T; Tzai, T-S; Wu, C-L

2010-01-01

The objective of this study was to develop an HER2-targeted, envelope-modified Moloney murine leukemia virus (MoMLV)-based gammaretroviral vector carrying interleukin (IL)-12 gene for bladder cancer therapy. It displayed a chimeric envelope protein containing a single-chain variable fragment (scFv) antibody to the HER2 receptor and carried the mouse IL-12 gene. The fragment of anti-erbB2scFv was constructed into the proline-rich region of the viral envelope of the packaging vector lacking a transmembrane subunit of the carboxyl terminal region of surface subunit. As compared with envelope-unmodified gammaretroviruses, envelope-modified ones had extended viral tropism to human HER2-expressing bladder cancer cell lines, induced apoptosis, and affected cell cycle progression despite lower viral titers. Moreover, animal studies showed that envelope-modified gammaretroviruses carrying IL-12 gene exerted higher antitumor activity in terms of retarding tumor growth and prolonging the survival of tumor-bearing mice than unmodified ones, which were associated with enhanced tumor cell apoptosis as well as increased intratumoral levels of IL-12, interferon-gamma, IL-1beta, and tumor necrosis factor-alpha proteins. Therefore, the antitumor activity of gammaretroviruses carrying the IL-12 gene was enhanced through genetic modification of the envelope targeting HER2 receptor, which may be a promising strategy for bladder cancer therapy.

Genetic diversity of the HpyC1I restriction modification system in Helicobacter pylori.

Science.gov (United States)

Lehours, Philippe; Dupouy, Sandrine; Chaineux, Julien; Ruskoné-Fourmestraux, Agnès; Delchier, Jean-Charles; Morgner, Andrea; Mégraud, Francis; Ménard, Armelle

2007-04-01

Helicobacter pylori is unique because of the unusually high number and diversity of its restriction modification (R-M) systems. HpyC1I R-M was recently characterized and contains an endonuclease which is an isoschizomer of the endonuclease BccI. This R-M is involved in adherence to gastric epithelial cells, a crucial step in bacterial pathogenesis. This observation illustrates the fact that R-M systems have other putative biological functions in addition to protecting the bacterial genome from external DNA. The genomic diversity of HpyC1I R-M was evaluated more precisely on a large collection of H. pylori strains by PCR, susceptibility to BccI digestion and sequencing. The results obtained support the mechanism of gain and loss of this R-M system in the H. pylori genome, and suggest that it is an ancestral system which gradually disappears during H. pylori evolution, following successive steps: (1) inactivation of the endonuclease gene, followed or accompanied by: (2) inactivation of the methyltransferase genes, and then: (3) definitive loss, leaving only short endonuclease remnant sequences.

Endogenous allergens and compositional analysis in the allergenicity assessment of genetically modified plants.

Science.gov (United States)

Fernandez, A; Mills, E N C; Lovik, M; Spoek, A; Germini, A; Mikalsen, A; Wal, J M

2013-12-01

Allergenicity assessment of genetically modified (GM) plants is one of the key pillars in the safety assessment process of these products. As part of this evaluation, one of the concerns is to assess that unintended effects (e.g. over-expression of endogenous allergens) relevant for the food safety have not occurred due to the genetic modification. Novel technologies are now available and could be used as complementary and/or alternative methods to those based on human sera for the assessment of endogenous allergenicity. In view of these developments and as a step forward in the allergenicity assessment of GM plants, it is recommended that known endogenous allergens are included in the compositional analysis as additional parameters to be measured. Copyright © 2013 Elsevier Ltd. All rights reserved.

75 FR 41529 - Petitions for Modification

Science.gov (United States)

2010-07-16

... application of existing mandatory safety standards published in Title 30 of the Code of Federal Regulations... DEPARTMENT OF LABOR Mine Safety and Health Administration Petitions for Modification AGENCY: Mine Safety and Health Administration (MSHA), Labor. ACTION: Notice of petitions for modification of existing...

75 FR 29784 - Petitions for Modification

Science.gov (United States)

2010-05-27

... application of existing mandatory safety standards published in Title 30 of the Code of Federal Regulations... DEPARTMENT OF LABOR Mine Safety and Health Administration Petitions for Modification AGENCY: Mine Safety and Health Administration (MSHA), Labor. ACTION: Notice of petitions for modification of existing...

75 FR 34486 - Petitions for Modification

Science.gov (United States)

2010-06-17

... application of existing mandatory safety standards published in Title 30 of the Code of Federal Regulations... DEPARTMENT OF LABOR Mine Safety and Health Administration Petitions for Modification AGENCY: Mine Safety and Health Administration (MSHA), Labor. ACTION: Notice of petitions for modification of existing...

Post-Translational Modifications of TRP Channels

Directory of Open Access Journals (Sweden)

Olaf Voolstra

2014-04-01

Full Text Available Transient receptor potential (TRP channels constitute an ancient family of cation channels that have been found in many eukaryotic organisms from yeast to human. TRP channels exert a multitude of physiological functions ranging from Ca2+ homeostasis in the kidney to pain reception and vision. These channels are activated by a wide range of stimuli and undergo covalent post-translational modifications that affect and modulate their subcellular targeting, their biophysical properties, or channel gating. These modifications include N-linked glycosylation, protein phosphorylation, and covalent attachment of chemicals that reversibly bind to specific cysteine residues. The latter modification represents an unusual activation mechanism of ligand-gated ion channels that is in contrast to the lock-and-key paradigm of receptor activation by its agonists. In this review, we summarize the post-translational modifications identified on TRP channels and, when available, explain their physiological role.

Genetic and non-iodine-related factors in the aetiology of nodular goitre

DEFF Research Database (Denmark)

Knudsen, Nils; Brix, Thomas Heiberg

2014-01-01

Genetic and a large number of environmental non-iodine-related factors play a role in the cause of nodular goitre. Most evidence for the influence of genetic and environmental factors in the cause of goitre is from cross-sectional, population-based studies. Only a few studies have included...... prospective data on risk factors for nodular goitre, although few prospective data are available on the effect of iodine and tobacco smoking on goitre development. Goitre is not one single phenotype. Many epidemiological studies do not distinguish diffuse from nodular goitre, as the investigated parameter...... is often thyroid volume or frequency with increased thyroid volume. Moreover, information on the presence and effect of gene-environment, gene-gene, and environment-environment effect modifications is limited. Thus, firm conclusions about the relative contributions and causality of the investigated risk...

Genetic differences in hemoglobin function between highland and lowland deer mice

DEFF Research Database (Denmark)

Storz, Jay F.; Runck, Amy M.; Moriyama, Hideaki

2010-01-01

In high-altitude vertebrates, adaptive changes in blood–O2 affinity may be mediated by modifications of hemoglobin (Hb) structure that affect intrinsic O2 affinity and/or responsiveness to allosteric effectors that modulate Hb–O2 affinity. This mode of genotypic specialization is considered typical...... of mammalian species that are high-altitude natives. Here we investigated genetically based differences in Hb–O2 affinity between highland and lowland populations of the deer mouse (Peromyscus maniculatus), a generalist species that has the broadest altitudinal distribution of any North American mammal....... The results of a combined genetic and proteomic analysis revealed that deer mice harbor a high level of Hb isoform diversity that is attributable to allelic polymorphism at two tandemly duplicated -globin genes and two tandemly duplicated β-globin genes. This high level of isoHb diversity translates...

Advanced technologies for genetically manipulating the silkworm Bombyx mori, a model Lepidopteran insect

Science.gov (United States)

Xu, Hanfu; O'Brochta, David A.

2015-01-01

Genetic technologies based on transposon-mediated transgenesis along with several recently developed genome-editing technologies have become the preferred methods of choice for genetically manipulating many organisms. The silkworm, Bombyx mori, is a Lepidopteran insect of great economic importance because of its use in silk production and because it is a valuable model insect that has greatly enhanced our understanding of the biology of insects, including many agricultural pests. In the past 10 years, great advances have been achieved in the development of genetic technologies in B. mori, including transposon-based technologies that rely on piggyBac-mediated transgenesis and genome-editing technologies that rely on protein- or RNA-guided modification of chromosomes. The successful development and application of these technologies has not only facilitated a better understanding of B. mori and its use as a silk production system, but also provided valuable experiences that have contributed to the development of similar technologies in non-model insects. This review summarizes the technologies currently available for use in B. mori, their application to the study of gene function and their use in genetically modifying B. mori for biotechnology applications. The challenges, solutions and future prospects associated with the development and application of genetic technologies in B. mori are also discussed. PMID:26108630

An improved genetic algorithm for designing optimal temporal patterns of neural stimulation

Science.gov (United States)

Cassar, Isaac R.; Titus, Nathan D.; Grill, Warren M.

2017-12-01

Objective. Electrical neuromodulation therapies typically apply constant frequency stimulation, but non-regular temporal patterns of stimulation may be more effective and more efficient. However, the design space for temporal patterns is exceedingly large, and model-based optimization is required for pattern design. We designed and implemented a modified genetic algorithm (GA) intended for design optimal temporal patterns of electrical neuromodulation. Approach. We tested and modified standard GA methods for application to designing temporal patterns of neural stimulation. We evaluated each modification individually and all modifications collectively by comparing performance to the standard GA across three test functions and two biophysically-based models of neural stimulation. Main results. The proposed modifications of the GA significantly improved performance across the test functions and performed best when all were used collectively. The standard GA found patterns that outperformed fixed-frequency, clinically-standard patterns in biophysically-based models of neural stimulation, but the modified GA, in many fewer iterations, consistently converged to higher-scoring, non-regular patterns of stimulation. Significance. The proposed improvements to standard GA methodology reduced the number of iterations required for convergence and identified superior solutions.

Roles of Vascular and Metabolic Components in Cognitive Dysfunction of Alzheimer disease: Short- and Long-term Modification by Non-genetic Risk Factors

Directory of Open Access Journals (Sweden)

Naoyuki eSato

2013-11-01

Full Text Available It is well known that a specific set of genetic and non-genetic risk factors contributes to the onset of Alzheimer disease (AD. Non-genetic risk factors include diabetes, hypertension in mid-life, and probably dyslipidemia in mid-life. This review focuses on the vascular and metabolic components of non-genetic risk factors. The mechanisms whereby non-genetic risk factors modify cognitive dysfunction are divided into four components, short- and long-term effects of vascular and metabolic factors. These consist of 1 compromised vascular reactivity, 2 vascular lesions, 3 hypo/hyperglycemia, and 4 exacerbated AD histopathological features, respectively. Vascular factors compromise cerebrovascular reactivity in response to neuronal activity and also cause irreversible vascular lesions. On the other hand, representative short-term effects of metabolic factors on cognitive dysfunction occur due to hypoglycemia or hyperglycemia. Non-genetic risk factors also modify the pathological manifestations of AD in the long-term. Therefore, vascular and metabolic factors contribute to aggravation of cognitive dysfunction in AD through short-term and long-term effects. Beta-amyloid could be involved in both vascular and metabolic components. It might be beneficial to support treatment in AD patients by appropriate therapeutic management of non-genetic risk factors, considering the contributions of these four elements to the manifestation of cognitive dysfunction in individual patients, though all components are not always present. It should be clarified how these four components interact with each other. To answer this question, a clinical prospective study that follows up clinical features with respect to these four components: 1 functional MRI or SPECT for cerebrovascular reactivity, 2 MRI for ischemic lesions and atrophy, 3 clinical episodes of hypoglycemia and hyperglycemia, 4 amyloid-PET and tau-PET for pathological features of AD, would be required.

Roles of vascular and metabolic components in cognitive dysfunction of Alzheimer disease: short- and long-term modification by non-genetic risk factors.

Science.gov (United States)

Sato, Naoyuki; Morishita, Ryuichi

2013-11-05

It is well known that a specific set of genetic and non-genetic risk factors contributes to the onset of Alzheimer disease (AD). Non-genetic risk factors include diabetes, hypertension in mid-life, and probably dyslipidemia in mid-life. This review focuses on the vascular and metabolic components of non-genetic risk factors. The mechanisms whereby non-genetic risk factors modify cognitive dysfunction are divided into four components, short- and long-term effects of vascular and metabolic factors. These consist of (1) compromised vascular reactivity, (2) vascular lesions, (3) hypo/hyperglycemia, and (4) exacerbated AD histopathological features, respectively. Vascular factors compromise cerebrovascular reactivity in response to neuronal activity and also cause irreversible vascular lesions. On the other hand, representative short-term effects of metabolic factors on cognitive dysfunction occur due to hypoglycemia or hyperglycemia. Non-genetic risk factors also modify the pathological manifestations of AD in the long-term. Therefore, vascular and metabolic factors contribute to aggravation of cognitive dysfunction in AD through short-term and long-term effects. β-amyloid could be involved in both vascular and metabolic components. It might be beneficial to support treatment in AD patients by appropriate therapeutic management of non-genetic risk factors, considering the contributions of these four elements to the manifestation of cognitive dysfunction in individual patients, though all components are not always present. It should be clarified how these four components interact with each other. To answer this question, a clinical prospective study that follows up clinical features with respect to these four components: (1) functional MRI or SPECT for cerebrovascular reactivity, (2) MRI for ischemic lesions and atrophy, (3) clinical episodes of hypoglycemia and hyperglycemia, (4) amyloid-PET and tau-PET for pathological features of AD, would be required.

Modification-specific proteomics: strategies for characterization of post-translational modifications using enrichment techniques

DEFF Research Database (Denmark)

Zhao, Yingming; Jensen, Ole N

2009-01-01

More than 300 different types of protein post-translational modifications (PTMs) have been described, many of which are known to have pivotal roles in cellular physiology and disease. Nevertheless, only a handful of PTMs have been extensively investigated at the proteome level. Knowledge of protein...... substrates and their PTM sites is key to dissection of PTM-mediated cellular processes. The past several years have seen a tremendous progress in developing MS-based proteomics technologies for global PTM analysis, including numerous studies of yeast and other microbes. Modification-specific enrichment...

SMRT Sequencing Revealed Mitogenome Characteristics and Mitogenome-Wide DNA Modification Pattern in Ophiocordyceps sinensis.

Science.gov (United States)

Kang, Xincong; Hu, Liqin; Shen, Pengyuan; Li, Rui; Liu, Dongbo

2017-01-01

Single molecule, real-time (SMRT) sequencing was used to characterize mitochondrial (mt) genome of Ophiocordyceps sinensis and to analyze the mt genome-wide pattern of epigenetic DNA modification. The complete mt genome of O. sinensis , with a size of 157,539 bp, is the fourth largest Ascomycota mt genome sequenced to date. It contained 14 conserved protein-coding genes (PCGs), 1 intronic protein rps3 , 27 tRNAs and 2 rRNA subunits, which are common characteristics of the known mt genomes in Hypocreales. A phylogenetic tree inferred from 14 PCGs in Pezizomycotina fungi supports O. sinensis as most closely related to Hirsutella rhossiliensis in Ophiocordycipitaceae. A total of 36 sequence sites in rps3 were under positive selection, with dN/dS >1 in the 20 compared fungi. Among them, 16 sites were statistically significant. In addition, the mt genome-wide base modification pattern of O. sinensis was determined in this study, especially DNA methylation. The methylations were located in coding and uncoding regions of mt PCGs in O. sinensis , and might be closely related to the expression of PCGs or the binding affinity of transcription factor A to mtDNA. Consequently, these methylations may affect the enzymatic activity of oxidative phosphorylation and then the mt respiratory rate; or they may influence mt biogenesis. Therefore, methylations in the mitogenome of O. sinensis might be a genetic feature to adapt to the cold and low PO 2 environment at high altitude, where O. sinensis is endemic. This is the first report on epigenetic modifications in a fungal mt genome.

Modifications at operating nuclear power plants

International Nuclear Information System (INIS)

Duffy, T.J.; Gazda, P.A.

1985-01-01

Modifications at operating nuclear power plants offer the structural engineer many challenges in the areas of scheduling of work, field adjustments, and engineering staff planning. The scheduling of structural modification work for operating nuclear power plants is normally closely tied to planned or unplanned outages of the plant. Coordination between the structural engineering effort, the operating plant staff, and the contractor who will be performing the modifications is essential to ensure that all work can be completed within the allotted time. Due to the inaccessibility of some areas in operating nuclear power plants or the short time available to perform the structural engineering in the case of an unscheduled outrage, field verification of a design is not always possible prior to initiating the construction of the modification. This requires the structural engineer to work closely with the contractor to promptly resolve problems due to unanticipated interferences or material procurement problems that may arise during the course of construction. The engineering staff planning for structural modifications at an operating nuclear power plant must be flexible enough to permit rapid response to the common ''fire drills,'' but controlled enough to ensure technically correct designs and to minimize the expenditure of man-hours and the resulting engineering cost

Standard approach to plant modifications

International Nuclear Information System (INIS)

Mecredy, R.C.

1988-01-01

Organizational and management approaches to the design, installation, and turnover of nuclear plant modifications have changed dramatically in the last 10 to 15 yr. In response to these changes, organizational and individual responsibilities have been defined and management systems have been established at Rochester Gas and Electric (RG and E) Corporation to ensure that high-quality plant modifications are installed in a timely manner that satisfies user needs at minimal cost

Efficient reanalysis of structures by a direct modification method. [local stiffness modifications of large structures

Science.gov (United States)

Raibstein, A. I.; Kalev, I.; Pipano, A.

1976-01-01

A procedure for the local stiffness modifications of large structures is described. It enables structural modifications without an a priori definition of the changes in the original structure and without loss of efficiency due to multiple loading conditions. The solution procedure, implemented in NASTRAN, involved the decomposed stiffness matrix and the displacement vectors of the original structure. It solves the modified structure exactly, irrespective of the magnitude of the stiffness changes. In order to investigate the efficiency of the present procedure and to test its applicability within a design environment, several real and large structures were solved. The results of the efficiency studies indicate that the break-even point of the procedure varies between 8% and 60% stiffness modifications, depending upon the structure's characteristics and the options employed.

The computational nature of memory modification

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-01-01

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature. DOI: http://dx.doi.org/10.7554/eLife.23763.001 PMID:28294944

Technical evaluation report on the proposed design modifications and technical-specification changes on grid voltage degradation for the San Onofre Nuclear Genetating Station, Unit 1

International Nuclear Information System (INIS)

Selan, J.C.

1982-01-01

This report documents the technical evaluation of the proposed design modifications and Technical Specification changes for protection of Class 1E equipment from grid voltage degradation for the San Onofre Nuclear Generating Station, Unit 1. The review criteria are based on several IEEE standards and the Code of Federal Regulations. The evaluation finds that the proposed design modifications and Technical Specification changes will ensure that the Class 1E equipment will be protected from sustained voltage degradation

23 CFR 630.110 - Modification of original agreement.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Modification of original agreement. 630.110 Section 630... OPERATIONS PRECONSTRUCTION PROCEDURES Project Authorization and Agreements § 630.110 Modification of original agreement. (a) When changes are needed to the original project agreement, a modification of agreement shall...

[Dignity or integrity - does the genetic modification of animals require new concepts in animal ethics?].

Science.gov (United States)

Schmidt, Kirsten

2008-01-01

Animal genetic engineering seems to point at a normative gap beyond pathocentric welfare theories in animal ethics. Recently developed approaches aim to bridge this gap by means of new normative criteria such as animal dignity and animal integrity. The following comparison of dignity and integrity in the context of animal ethics shows that the dignity concept faces serious problems because of its necessarily anthroporelational character and the different functions of contingent and inherent dignity within ethical reasoning. Unlike animal dignity the concept of animal integrity could prove to be a useful enhancement for pathocentric approaches.

Surface modification of ceramics. Ceramics no hyomen kaishitsu

Energy Technology Data Exchange (ETDEWEB)

Hioki, T. (Toyota Central Research and Development Labs., Inc., Nagoya (Japan))

1993-07-05

Surface modification of ceramics and some study results using in implantation in surface modification are introduced. The mechanical properties (strength, fracture toughness, flaw resistance) of ceramics was improved and crack was repaired using surface modification by ion implantation. It is predicted that friction and wear properties are considerably affected because the hardness of ceramics is changed by ion implantation. Cementing and metalization are effective as methods for interface modification and the improvement of the adhesion power of the interface between metal and ceramic is their example. It was revealed that the improvement of mechanical properties of ceramics was achieved if appropriate surface modification was carried out. The market of ceramics mechanical parts is still small, therefore, the present situation is that the field of activities for surface modification of ceramics is also narrow. However, it is thought that in future, ceramics use may be promoted surely in the field like medicine and mechatronics. 8 refs., 4 figs.

Monster potential meets potential monster: pros and cons of deploying genetically modified microalgae for biofuels production.

Science.gov (United States)

Flynn, K J; Mitra, A; Greenwell, H C; Sui, J

2013-02-06

Biofuels production from microalgae attracts much attention but remains an unproven technology. We explore routes to enhance production through modifications to a range of generic microalgal physiological characteristics. Our analysis shows that biofuels production may be enhanced ca fivefold through genetic modification (GM) of factors affecting growth rate, respiration, photoacclimation, photosynthesis efficiency and the minimum cell quotas for nitrogen and phosphorous (N : C and P : C). However, simulations indicate that the ideal GM microalgae for commercial deployment could, on escape to the environment, become a harmful algal bloom species par excellence, with attendant risks to ecosystems and livelihoods. In large measure, this is because an organism able to produce carbohydrate and/or lipid at high rates, providing stock metabolites for biofuels production, will also be able to attain a stoichiometric composition that will be far from optimal as food for the support of zooplankton growth. This composition could suppress or even halt the grazing activity that would otherwise control the microalgal growth in nature. In consequence, we recommend that the genetic manipulation of microalgae, with inherent consequences on a scale comparable to geoengineering, should be considered under strict international regulation.

Structural dynamic modification

Indian Academy of Sciences (India)

and stiffness matrices) andaor modal parameters, in order to acquire some ... For the above reasons, another modification approach is presented here ... The data necessary to solve the direct problem are dynamic behaviour of the original.

Substantial equivalence--an appropriate paradigm for the safety assessment of genetically modified foods?

International Nuclear Information System (INIS)

Kuiper, Harry A.; Kleter, Gijs A.; Noteborn, Hub P.J.M.; Kok, Esther J.

2002-01-01

Safety assessment of genetically modified food crops is based on the concept of substantial equivalence, developed by OECD and further elaborated by FAO/WHO. The concept embraces a comparative approach to identify possible differences between the genetically modified food and its traditional comparator, which is considered to be safe. The concept is not a safety assessment in itself, it identifies hazards but does not assess them. The outcome of the comparative exercise will further guide the safety assessment, which may include (immuno)toxicological and biochemical testing. Application of the concept of substantial equivalence may encounter practical difficulties: (i) the availability of near-isogenic parental lines to compare the genetically modified food with; (ii) limited availability of methods for the detection of (un)intended effects resulting from the genetic modification; and (iii) limited information on natural variations in levels of relevant crop constituents. In order to further improve the methodology for identification of unintended effects, new 'profiling' methods are recommended. Such methods will allow for the screening of potential changes in the modified host organism at different integration levels, i.e. at the genome level, during gene expression and protein translation, and at the level of cellular metabolism

Genetic engineering of industrial Saccharomyces cerevisiae strains using a selection/counter-selection approach.

Science.gov (United States)

Kutyna, Dariusz R; Cordente, Antonio G; Varela, Cristian

2014-01-01

Gene modification of laboratory yeast strains is currently a very straightforward task thanks to the availability of the entire yeast genome sequence and the high frequency with which yeast can incorporate exogenous DNA into its genome. Unfortunately, laboratory strains do not perform well in industrial settings, indicating the need for strategies to modify industrial strains to enable strain development for industrial applications. Here we describe approaches we have used to genetically modify industrial strains used in winemaking.

Investigating MCTS Modifications in General Video Game Playing

DEFF Research Database (Denmark)

Frydenberg, Frederik; Andersen, Kasper; Risi, Sebastian

2015-01-01

-style video games. This paper investigates of how well these modifications perform in general video game playing using the general video game AI (GVG-AI) framework and introduces a new MCTS modification called UCT reverse penalty that penalizes the MCTS controller for exploring recently visited children......While Monte Carlo tree search (MCTS) methods have shown promise in a variety of different board games, more complex video games still present significant challenges. Recently, several modifications to the core MCTS algorithm have been proposed with the hope to increase its effectiveness on arcade....... The results of our experiments show that a combination of two MCTS modifications can improve the performance of the vanilla MCTS controller, but the effectiveness of the modifications highly depends on the particular game being played....

Minimal modification to tribimaximal mixing

International Nuclear Information System (INIS)

He Xiaogang; Zee, A.

2011-01-01

We explore some ways of minimally modifying the neutrino mixing matrix from tribimaximal, characterized by introducing at most one mixing angle and a CP violating phase thus extending our earlier work. One minimal modification, motivated to some extent by group theoretic considerations, is a simple case with the elements V α2 of the second column in the mixing matrix equal to 1/√(3). Modifications by keeping one of the columns or one of the rows unchanged from tribimaximal mixing all belong to the class of minimal modification. Some of the cases have interesting experimentally testable consequences. In particular, the T2K and MINOS collaborations have recently reported indications of a nonzero θ 13 . For the cases we consider, the new data sharply constrain the CP violating phase angle δ, with δ close to 0 (in some cases) and π disfavored.

Disassembling and modification of RA-3

International Nuclear Information System (INIS)

Tarizzo, R.D.

1990-01-01

The objective of this paper is to describe the partial disassembling and modification of RA-3, called the Modernization Project. It comprises all the technical and administrative steps directly related with this task. The improvement of RA-3 is a result of the lack of 90% enriched uranium obliging a change over to 20% enriched uranium. This brought about design modifications both in fuel elements and the reactor. The presentation of documents for the licensing authority as well as are detailed separately. The modernization project was divided in 25 tasks: 1) changing fuel element support table, 2) changing heat exchanger, 3) repairing of cooling towers, 4) repairing of primary circuit valves, 5) repairing of irradiation channels, 6) construction of a new sampler, 7) changing tangential channel, 8) cleaning and disassembling of reactor (inside), 9) changing continuous demineralizer (ion exchange column), 10) detection of failure in fuel elements, 11) modification of nuclear instrumentation, 12) modification of conventional instrumentation, 13) modification of electrical system, 14) changing telemanipulators, 15) construction of mechanism bridge, 16) changing a primary circuit valve when the heat exchanger is changed too, 17) painting ground floor, hall floor, and pump room floor with epoxy resin levelling, 18) installation of fire alarm system, 19) radioactive liquid discharge, 20) modification of secondary circuit (This task involves: a) installation of a third secondary pump, b) extension of this piping, c) installation of two 12 inch valves to the present cooling towers pools independent, d) installation of filtering system), 21) optimization hot water bed, 22) changing detector support table, 23) removal, decontamination and reinstallation of shielding, 25) changing pneumatic system

Low genetic diversity and strong population structure shaped by anthropogenic habitat fragmentation in a critically endangered primate, Trachypithecus leucocephalus.

Science.gov (United States)

Wang, W; Qiao, Y; Li, S; Pan, W; Yao, M

2017-06-01

Habitat fragmentation may strongly impact population genetic structure and reduce the genetic diversity and viability of small and isolated populations. The white-headed langur (Trachypithecus leucocephalus) is a critically endangered primate species living in a highly fragmented and human-modified habitat in southern China. We examined the population genetic structure and genetic diversity of the species and investigated the environmental and anthropogenic factors that may have shaped its population structure. We used 214 unique multi-locus genotypes from 41 social groups across the main distribution area of T. leucocephalus, and found strong genetic structure and significant genetic differentiation among local populations. Our landscape genetic analyses using a causal modelling framework suggest that a large habitat gap and geographical distance represent the primary landscape elements shaping genetic structure, yet high levels of genetic differentiation also exist between patches separated by a small habitat gap or road. This is the first comprehensive study that has evaluated the population genetic structure and diversity of T. leucocephalus using nuclear markers. Our results indicate strong negative impacts of anthropogenic land modifications and habitat fragmentation on primate genetic connectivity between forest patches. Our analyses suggest that two management units of the species could be defined, and indicate that habitat continuity should be enforced and restored to reduce genetic isolation and enhance population viability.

Modification degrees at specific sites on heparan sulphate: an approach to measure chemical modifications on biological molecules with stable isotope labelling

Science.gov (United States)

Wu, Zhengliang L.; Lech, Miroslaw

2005-01-01

Chemical modification of biological molecules is a general mechanism for cellular regulation. A quantitative approach has been developed to measure the extent of modification on HS (heparan sulphates). Sulphation on HS by sulphotransferases leads to variable sulphation levels, which allows cells to tune their affinities to various extracellular proteins, including growth factors. With stable isotope labelling and HPLC-coupled MS, modification degrees at various O-sulphation sites could be determined. A bovine kidney HS sample was first saturated in vitro with 34S by an OST (O-sulphotransferase), then digested with nitrous acid and analysed with HPLC-coupled MS. The 34S-labelled oligosaccharides were identified based on their unique isotope clusters. The modification degrees at the sulphotransferase recognition sites were obtained by calculating the intensities of isotopic peaks in the isotope clusters. The modification degrees at 3-OST-1 and 6-OST-1 sites were examined in detail. This approach can also be used to study other types of chemical modifications on biological molecules. PMID:15743272

Stress-induced variation in evolution: from behavioural plasticity to genetic assimilation.

Science.gov (United States)

Badyaev, Alexander V

2005-05-07

Extreme environments are closely associated with phenotypic evolution, yet the mechanisms behind this relationship are poorly understood. Several themes and approaches in recent studies significantly further our understanding of the importance that stress-induced variation plays in evolution. First, stressful environments modify (and often reduce) the integration of neuroendocrinological, morphological and behavioural regulatory systems. Second, such reduced integration and subsequent accommodation of stress-induced variation by developmental systems enables organismal 'memory' of a stressful event as well as phenotypic and genetic assimilation of the response to a stressor. Third, in complex functional systems, a stress-induced increase in phenotypic and genetic variance is often directional, channelled by existing ontogenetic pathways. This accounts for similarity among individuals in stress-induced changes and thus significantly facilitates the rate of adaptive evolution. Fourth, accumulation of phenotypically neutral genetic variation might be a common property of locally adapted and complex organismal systems, and extreme environments facilitate the phenotypic expression of this variance. Finally, stress-induced effects and stress-resistance strategies often persist for several generations through maternal, ecological and cultural inheritance. These transgenerational effects, along with both the complexity of developmental systems and stressor recurrence, might facilitate genetic assimilation of stress-induced effects. Accumulation of phenotypically neutral genetic variance by developmental systems and phenotypic accommodation of stress-induced effects, together with the inheritance of stress-induced modifications, ensure the evolutionary persistence of stress-response strategies and provide a link between individual adaptability and evolutionary adaptation.

Epigenetic Modifications: Therapeutic Potential in Cancer

Directory of Open Access Journals (Sweden)

Manisha Sachan

2015-08-01

Full Text Available Epigenetic modifications and alterations in chromatin structure and function contribute to the cumulative changes observed as normal cells undergo malignant transformation. These modifications and enzymes (DNA methyltransferases, histone deacetylases, histone methyltransferases, and demethylases related to them have been deeply studied to develop new drugs, epigenome-targeted therapies and new diagnostic tools. Epigenetic modifiers aim to restore normal epigenetic modification patterns through the inhibition of epigenetic modifier enzymes. Four of them (azacitidine, decitabine, vorinostat and romidepsin are approved by the U.S. Food and Drug Administration. This article provides an overview about the known functional roles of epigenetic enzymes in cancer development.

Interplay of Inflammatory Mediators with Epigenetics and Cartilage Modifications in Osteoarthritis

Directory of Open Access Journals (Sweden)

Swarna Raman

2018-03-01

Full Text Available Osteoarthritis (OA, a degenerative disease of diarthrodial joints, is influenced by mechanical and inflammatory factors with aging, obesity, chronic injuries, and secondary diseases thought to be major factors driving the process of articular cartilage degeneration. Chondrocytes, the cellular component of cartilage, reside in an avascular environment and normally have limited potential to replicate. However, extrinsic factors such as injury to the joint or intrinsic alterations to the chondrocytes themselves can lead to an altered phenotype and development of OA. Synovial inflammation is also a pivotal element of the osteoarthritic, degenerative process: influx of pro-inflammatory cytokines and production of matrix metalloproteinases accelerate advanced cellular processes such as synovitis and cartilage damage. As well as a genetic input, recent data have highlighted epigenetic factors as contributing to disease. Studies conducted over the last decade have focused on three key aspects in OA; inflammation and the immune response, genome-wide association studies that have identified important genes undergoing epigenetic modifications, and finally how chondrocytes transform in their function during development and disease. Data highlighted here have identified critical inflammatory genes involved in OA and how these factors impact chondrocyte hypertrophy in the disease. This review also addresses key inflammatory factors in synovial inflammation, epigenetics, and chondrocyte fate, and how agents that inhibit epigenetic mechanisms like DNA methylation and histone modifications could aid in development of long-term treatment strategies for the disease.

14 CFR 21.9 - Replacement and modification articles.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to be...

Modification of metallic corrosion by ion implantation

International Nuclear Information System (INIS)

Clayton, C.R.

1981-01-01

This review will consider some of the properties of surface alloys, formed by ion implantation, which are effective in modifying corrosion behaviour. Examples will be given of the modification of the corrosion behaviour of pure metals, steels and other engineering alloys, resulting from implantation with metals and metalloids. Emphasis will be given to the modification of anodic processes produced by ion implantation since a review will be given elsewhere in the proceedings concerning the modification of cathodic processes. (orig.)

Production of marine plant biomass: Management, cultivation, and genetic modification of macrophytic algae

Science.gov (United States)

Vandermeer, J. P.

1982-12-01

Every second of every day, the Sun's fusion reactions convert thousands of tons of hydrogen into helium with the release of almost unimaginable amounts of energy. Through the photosynthetic activity of plants, both aquatic and terrestrial, a small fraction of this energy is trapped and stored as plant biomass. The oceans cover a greater fraction of the globe than do the land masses, making it appropriate to consider their contribution to the total biomass production, and their potential as a source of raw materials for the extraction of chemicals and fuels. A rather broad synthesis, convering the total seaweed resource and some of the constraints placed on harvesting these plants, attempts to farm the oceans to increase the supply of desirable species, attempts to cultivate seaweeds in enclosures where environmental parameters are controlled, and finally, the limited amount of genetic manipulation that was applied to these plants was presented. Only the larger red and brown seaweeds were considered because they represent the bulk of the biomass.

Large-Scale Culture and Genetic Modification of Human Natural Killer Cells for Cellular Therapy.

Science.gov (United States)

Lapteva, Natalia; Parihar, Robin; Rollins, Lisa A; Gee, Adrian P; Rooney, Cliona M

2016-01-01

Recent advances in methods for the ex vivo expansion of human natural killer (NK) cells have facilitated the use of these powerful immune cells in clinical protocols. Further, the ability to genetically modify primary human NK cells following rapid expansion allows targeting and enhancement of their immune function. We have successfully adapted an expansion method for primary NK cells from peripheral blood mononuclear cells or from apheresis products in gas permeable rapid expansion devices (G-Rexes). Here, we describe an optimized protocol for rapid and robust NK cell expansion as well as a method for highly efficient retroviral transduction of these ex vivo expanded cells. These methodologies are good manufacturing practice (GMP) compliant and could be used for clinical-grade product manufacturing.

Evolutionary changes of Hox genes and relevant regulatory factors provide novel insights into mammalian morphological modifications.

Science.gov (United States)

Li, Kui; Sun, Xiaohui; Chen, Meixiu; Sun, Yingying; Tian, Ran; Wang, Zhengfei; Xu, Shixia; Yang, Guang

2018-01-01

The diversity of body plans of mammals accelerates the innovation of lifestyles and the extensive adaptation to different habitats, including terrestrial, aerial and aquatic habitats. However, the genetic basis of those phenotypic modifications, which have occurred during mammalian evolution, remains poorly explored. In the present study, we synthetically surveyed the evolutionary pattern of Hox clusters that played a powerful role in the morphogenesis along the head-tail axis of animal embryos and the main regulatory factors (Mll, Bmi1 and E2f6) that control the expression of Hox genes. A deflected density of repetitive elements and lineage-specific radical mutations of Mll have been determined in marine mammals with morphological changes, suggesting that evolutionary changes may alter Hox gene expression in these lineages, leading to the morphological modification of these lineages. Although no positive selection was detected at certain ancestor nodes of lineages, the increased ω values of Hox genes implied the relaxation of functional constraints of these genes during the mammalian evolutionary process. More importantly, 49 positively-selected sites were identified in mammalian lineages with phenotypic modifications, indicating adaptive evolution acting on Hox genes and regulatory factors. In addition, 3 parallel amino acid substitutions in some Hox genes were examined in marine mammals, which might be responsible for their streamlined body. © 2017 The Authors. Integrative Zoology published by International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Genetically modified organisms in light of domestic and world regulations

Directory of Open Access Journals (Sweden)

Nikolić Zorica

2007-01-01

Full Text Available At the same time as development and registration of new genetic modification of plant species have intensified, the number of countries in which they are grown has also increased considerably. Genetically modified crops were grown in 22 countries in 2006, six of which were in European Union. Protocol on Biosafety, known as Cartagena protocol was adopted at the international level in February, 2000. Presence, but not growing of GMO in food is allowed in many countries, while in some others labeling of food origination from GMO is obligatory. Labeling is obligatory in European Union, Australia, New Zealand, Japan, Norway, Switzerland and some others. In our country the Law on GMO and sub-law acts were conceived according to EU regulative. The terms for limited use, production, trade of GMO and GMO products have been prescribed. Validation and standardization of GMO testing methods are now being implemented. It is expected that the analytical GMO methods will soon be harmonized at the international level. .

Genetic Manipulations of PPARs: Effects on Obesity and Metabolic Disease

Directory of Open Access Journals (Sweden)

Yaacov Barak

2007-01-01

Full Text Available The interest in genetic manipulations of PPARs is as old as their discovery as receptors of ligands with beneficial clinical activities. Considering the effects of PPAR ligands on critical aspects of systemic physiology, including obesity, lipid metabolism, insulin resistance, and diabetes, gene knockout (KO in mice is the ideal platform for both hypothesis testing and discovery of new PPAR functions in vivo. With the fervent pursuit of the magic bullet to eradicate the obesity epidemic, special emphasis has been placed on the impacts of PPARs on obesity and its associated diseases. As detailed in this review, understanding how PPARs regulate gene expression and basic metabolic pathways is a necessary intermediate en route to deciphering their effects on obesity. Over a decade and dozens of genetic modifications of PPARs into this effort, valuable lessons have been learned, but we are left with more questions to be answered. These lessons and future prospects are the subject of this review.

TWO MODIFICATIONS OF SCALERS FOR RATE STUDIES

Energy Technology Data Exchange (ETDEWEB)

Hodgson, T. S.; Gordon, B. E.

1964-04-15

Two simple modifications to nuclear scalers have been developed. The first involves an automatic stepping switch which permits a single scaler to be actuated by up to four Geiger counters in sequence and to record the time to reach a preset count for each. The second modification is designed to pick a pulse off a conventional scaler when a preset count has been reached and to use the pulse to actuate a recorder. Both modifications considerably extend the utility of conventional scalers.

Recent Developments on Genetic Engineering of Microalgae for Biofuels and Bio-Based Chemicals.

Science.gov (United States)

Ng, I-Son; Tan, Shih-I; Kao, Pei-Hsun; Chang, Yu-Kaung; Chang, Jo-Shu

2017-10-01

Microalgae serve as a promising source for the production of biofuels and bio-based chemicals. They are superior to terrestrial plants as feedstock in many aspects and their biomass is naturally rich in lipids, carbohydrates, proteins, pigments, and other valuable compounds. Due to the relatively slow growth rate and high cultivation cost of microalgae, to screen efficient and robust microalgal strains as well as genetic modifications of the available strains for further improvement are of urgent demand in the development of microalgae-based biorefinery. In genetic engineering of microalgae, transformation and selection methods are the key steps to accomplish the target gene modification. However, determination of the preferable type and dosage of antibiotics used for transformant selection is usually time-consuming and microalgal-strain-dependent. Therefore, more powerful and efficient techniques should be developed to meet this need. In this review, the conventional and emerging genome-editing tools (e.g., CRISPR-Cas9, TALEN, and ZFN) used in editing the genomes of nuclear, mitochondria, and chloroplast of microalgae are thoroughly surveyed. Although all the techniques mentioned above demonstrate their abilities to perform gene editing and desired phenotype screening, there still need to overcome higher production cost and lower biomass productivity, to achieve efficient production of the desired products in microalgal biorefineries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modifications of the Weibull distribution: A review

International Nuclear Information System (INIS)

Almalki, Saad J.; Nadarajah, Saralees

2014-01-01

It is well known that the Weibull distribution is the most popular and the most widely used distribution in reliability and in analysis of lifetime data. Unfortunately, its hazard function cannot exhibit non-monotonic shapes like the bathtub shape or the unimodal shape. Since 1958, the Weibull distribution has been modified by many researchers to allow for non-monotonic hazard functions. This paper gives an extensive review of some discrete and continuous versions of the modifications of the Weibull distribution. - Highlights: • A comprehensive review of known discrete modifications and generalizations of the Weibull distribution. • A comprehensive review of known continuous modifications and generalizations of the Weibull distribution. • Over 110 references on modifications/generalizations of the Weibull distribution. • More than 55% of the cited references appeared in the last 5 years

Genetic engineering of microorganisms for biodiesel production

Science.gov (United States)

Lin, Hui; Wang, Qun; Shen, Qi; Zhan, Jumei; Zhao, Yuhua

2013-01-01

Biodiesel, as one type of renewable energy, is an ideal substitute for petroleum-based diesel fuel and is usually made from triacylglycerides by transesterification with alcohols. Biodiesel production based on microbial fermentation aiming to establish more efficient, less-cost and sustainable biodiesel production strategies is under current investigation by various start-up biotechnology companies and research centers. Genetic engineering plays a key role in the transformation of microbes into the desired cell factories with high efficiency of biodiesel production. Here, we present an overview of principal microorganisms used in the microbial biodiesel production and recent advances in metabolic engineering for the modification required. Overexpression or deletion of the related enzymes for de novo synthesis of biodiesel is highlighted with relevant examples. PMID:23222170

Assessment of the safety of foods derived from genetically modified (GM) crops

DEFF Research Database (Denmark)

Konig, A.; Cockburn, A.; Crewel, R. W. R.

2004-01-01

of the modified crop and the introduced trait, and assessing potential unintended effects from the genetic modification. The proposed approach to safety assessment starts with the comparison of the new GM crop with a traditional counterpart that is generally accepted as safe based on a history of human food use......This paper provides guidance on how to assess the safety of foods derived from genetically modified crops (GM crops); it summarises conclusions and recommendations of Working Group I of the ENTRANSFOOD project. The paper provides an approach for adapting the test strategy to the characteristics...... (the concept of substantial equivalence). This case-focused approach ensures that foods derived from GM crops that have passed this extensive test-regime are as safe and nutritious as currently consumed plant-derived foods. The approach is suitable for current and future GM crops with more complex...

Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study

Science.gov (United States)

Weisskopf, Marc G.; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

2016-01-01

Background Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. Objectives We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. Methods We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Results Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50–3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Conclusions Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data. PMID:27584680

Three Sisters Dam modifications and performance

Energy Technology Data Exchange (ETDEWEB)

Courage, L.J.R. [Monenco AGRA Inc., Calgary, AB (Canada)

1995-12-31

Recent modifications and maintenance carried out at the Three Sisters Dam, in the Alberta Rockies south of the town of Canmore, were described. A detailed account was given of the dam`s geological setting, its abnormally high leakage through the foundation and its sinkhole activity. Results of studies aimed at finding the cause of leakage and sinkhole occurrences were reviewed. Modifications made to the dam since 1951 were detailed, as were modifications to handle probable maximum flood levels. Three approaches for estimating failure probabilities after identification of failure modes were described. The overall conclusion was that based on constant leakage, no settlement in the dam, penstocks, or the powerhouse since construction, the Three Sisters Dam was stable. 1 ref.

[Sporulation or competence development? A genetic regulatory network model of cell-fate determination in Bacillus subtilis].

Science.gov (United States)

Lu, Zhenghui; Zhou, Yuling; Zhang, Xiaozhou; Zhang, Guimin

2015-11-01

Bacillus subtilis is a generally recognized as safe (GRAS) strain that has been widely used in industries including fodder, food, and biological control. In addition, B. subtilis expression system also plays a significant role in the production of industrial enzymes. However, its application is limited by its low sporulation frequency and transformation efficiency. Immense studies have been done on interpreting the molecular mechanisms of sporulation and competence development, whereas only few of them were focused on improving sporulation frequency and transformation efficiency of B. subtilis by genetic modification. The main challenge is that sporulation and competence development, as the two major developmental events in the stationary phase of B. subtilis, are regulated by the complicated intracellular genetic regulatory systems. In addition, mutual regulatory mechanisms also exist in these two developmental events. With the development of genetic and metabolic engineering, constructing genetic regulatory networks is currently one of the most attractive research fields, together with the genetic information of cell growth, metabolism, and development, to guide the industrial application. In this review, the mechanisms of sporulation and competence development of B. subtilis, their interactions, and the genetic regulation of cell growth were interpreted. In addition, the roles of these regulatory networks in guiding basic and applied research of B. subtilis and its related species were discussed.

CRISPR/Cas9 : A molecular Swiss army knife for simultaneous introduction of multiple genetic modifications in Saccharomyces cerevisiae

NARCIS (Netherlands)

Mans, R.; Van Rossum, H.M.; Wijsman, M.; Backx, A.; Kuijpers, N.G.A.; van den Broek, M.; Daran-Lapujade, P.A.S.; Pronk, J.T.; Van Maris, A.J.A.; Daran, J.G.

2015-01-01

A variety of techniques for strain engineering in Saccharomyces cerevisiae have recently been developed. However, especially when multiple genetic manipulations are required, strain construction is still a time-consuming process. This study describes new CRISPR/Cas9-based approaches for easy, fast

Microscopic mechanism of amino silicone oil modification and modification effect with different amino group contents based on molecular dynamics simulation

Science.gov (United States)

He, Liping; Li, Wenjun; Chen, Dachuan; Yuan, Jianmin; Lu, Gang; Zhou, Dianwu

2018-05-01

The microscopic mechanism of amino silicone oil (ASO) modification of natural fiber was investigated for the first time using molecular dynamics (MD) simulation at the atomic and molecular levels. The MD simulation results indicated that the ASO molecular interacted with the cellulose molecular within the natural fiber, mainly by intermolecular forces of Nsbnd Hsbnd O and Osbnd Hsbnd N hydrogen bonds and the molecular chain of ASO absorbed onto the natural fiber in a selective orientation, i.e., the hydrophobic alkyl groups (sbnd CnH2n+1) project outward and the polar amino groups (sbnd NH2) point to the surface of natural fiber. Consequently, the ASO modification changed the surface characteristic of natural fiber from hydrophilic to hydrophobic. Furthermore, the modification effects of the ASO modification layer with different amino group contents (m:n ratio) were also evaluated in this study by calculating the binding energy between the ASO modifier and natural fiber, and the cohesive energy density and free volume of the ASO modification layer. The results showed that the binding energy reached a maximum when the m:n ratio of ASO was of 8:4, suggesting that a good bonding strength was achieved at this m:n ratio. It was also found that the cohesive energy density enhanced with the increase in the amino group content, and the higher the cohesive energy density, the easier the formation of the ASO modification layer. However, the fraction free volume decreased with the increase in the amino group content. This is good for improving the water-proof property of natural fiber. The present work can provide an effective method for predicting the modification effects and designing the optimized m:n ratio of ASO modification.

Posttranslational Modification Biology of Glutamate Receptors and Drug Addiction

Directory of Open Access Journals (Sweden)

Li-Min eMao

2011-03-01

Full Text Available Posttranslational covalent modifications of glutamate receptors remain a hot topic. Early studies have established that this family of receptors, including almost all ionotropic and metabotropic glutamate receptor subtypes, undergoes active phosphorylation at serine, threonine, or tyrosine residues on their intracellular domains. Recent evidence identifies several glutamate receptor subtypes to be direct substrates for palmitoylation at cysteine residues. Other modifications such as ubiquitination and sumoylation at lysine residues also occur to certain glutamate receptors. These modifications are dynamic and reversible in nature and are regulatable by changing synaptic inputs. The regulated modifications significantly impact the receptor in many ways, including interrelated changes in biochemistry (synthesis, subunit assembling and protein-protein interactions, subcellular redistribution (trafficking, endocytosis, synaptic delivery and clustering, and physiology, usually associated with changes in synaptic plasticity. Glutamate receptors are enriched in the striatum and cooperate closely with dopamine to regulate striatal signaling. Emerging evidence shows that modification processes of striatal glutamate receptors are sensitive to addictive drugs, such as psychostimulants (cocaine and amphetamines. Altered modifications are believed to be directly linked to enduring receptor/synaptic plasticity and drug-seeking. This review summarizes several major types of modifications of glutamate receptors and analyzes the role of these modifications in striatal signaling and in the pathogenesis of psychostimulant addiction.

New Algorithm of Automatic Complex Password Generator Employing Genetic Algorithm

Directory of Open Access Journals (Sweden)

Sura Jasim Mohammed

2018-01-01

Full Text Available Due to the occurred increasing in information sharing, internet popularization, E-commerce transactions, and data transferring, security and authenticity become an important and necessary subject. In this paper an automated schema was proposed to generate a strong and complex password which is based on entering initial data such as text (meaningful and simple information or not, with the concept of encoding it, then employing the Genetic Algorithm by using its operations crossover and mutation to generated different data from the entered one. The generated password is non-guessable and can be used in many and different applications and internet services like social networks, secured system, distributed systems, and online services. The proposed password generator achieved diffusion, randomness, and confusions, which are very necessary, required and targeted in the resulted password, in addition to the notice that the length of the generated password differs from the length of initial data, and any simple changing and modification in the initial data produces more and clear modification in the generated password. The proposed work was done using visual basic programing language.

Comparative genome and methylome analysis reveals restriction/modification system diversity in the gut commensal Bifidobacterium breve

Science.gov (United States)

Bottacini, Francesca; Morrissey, Ruth; Roberts, Richard John; James, Kieran; van Breen, Justin; Egan, Muireann; Lambert, Jolanda; van Limpt, Kees; Knol, Jan; Motherway, Mary O’Connell; van Sinderen, Douwe

2018-01-01

Abstract Bifidobacterium breve represents one of the most abundant bifidobacterial species in the gastro-intestinal tract of breast-fed infants, where their presence is believed to exert beneficial effects. In the present study whole genome sequencing, employing the PacBio Single Molecule, Real-Time (SMRT) sequencing platform, combined with comparative genome analysis allowed the most extensive genetic investigation of this taxon. Our findings demonstrate that genes encoding Restriction/Modification (R/M) systems constitute a substantial part of the B. breve variable gene content (or variome). Using the methylome data generated by SMRT sequencing, combined with targeted Illumina bisulfite sequencing (BS-seq) and comparative genome analysis, we were able to detect methylation recognition motifs and assign these to identified B. breve R/M systems, where in several cases such assignments were confirmed by restriction analysis. Furthermore, we show that R/M systems typically impose a very significant barrier to genetic accessibility of B. breve strains, and that cloning of a methyltransferase-encoding gene may overcome such a barrier, thus allowing future functional investigations of members of this species. PMID:29294107

Sequence tagging reveals unexpected modifications in toxicoproteomics

Science.gov (United States)

Dasari, Surendra; Chambers, Matthew C.; Codreanu, Simona G.; Liebler, Daniel C.; Collins, Ben C.; Pennington, Stephen R.; Gallagher, William M.; Tabb, David L.

2010-01-01

Toxicoproteomic samples are rich in posttranslational modifications (PTMs) of proteins. Identifying these modifications via standard database searching can incur significant performance penalties. Here we describe the latest developments in TagRecon, an algorithm that leverages inferred sequence tags to identify modified peptides in toxicoproteomic data sets. TagRecon identifies known modifications more effectively than the MyriMatch database search engine. TagRecon outperformed state of the art software in recognizing unanticipated modifications from LTQ, Orbitrap, and QTOF data sets. We developed user-friendly software for detecting persistent mass shifts from samples. We follow a three-step strategy for detecting unanticipated PTMs in samples. First, we identify the proteins present in the sample with a standard database search. Next, identified proteins are interrogated for unexpected PTMs with a sequence tag-based search. Finally, additional evidence is gathered for the detected mass shifts with a refinement search. Application of this technology on toxicoproteomic data sets revealed unintended cross-reactions between proteins and sample processing reagents. Twenty five proteins in rat liver showed signs of oxidative stress when exposed to potentially toxic drugs. These results demonstrate the value of mining toxicoproteomic data sets for modifications. PMID:21214251

Ion bombardment modification of surfaces

International Nuclear Information System (INIS)

Auciello, O.

1984-01-01

Ion bombardment-induced modification of surfaces may be considered one of the significant scientific and technological developments of the last two decades. The understanding acquired concerning the underlying mechanisms of several phenomena occurring during ion-surface interactions has led to applications within different modern technologies. These include microelectronics, surface acoustical and optical technologies, solar energy conversion, thin film technology, ion implantation metallurgy, nuclear track technology, thermonuclear fusion, vacuum technology, cold welding technology, biomedicine (implantology). It has become clear that information on many relevant advances, regarding ion bombardment modification of surfaces is dispersed among journals involving fields sometimes not clearly related. This may result, in some cases, in a loss of the type of interdisciplinary exchange of ideas, which has proved to be so fruitful for the advancement of science and technology. This book has been planned in an attempt to collect at least some of today's relevant information about the experimental and theoretical knowledge related to surface modification and its application to technology. (Auth.)

Genetically modified (GM) crops: milestones and new advances in crop improvement.

Science.gov (United States)

Kamthan, Ayushi; Chaudhuri, Abira; Kamthan, Mohan; Datta, Asis

2016-09-01

New advances in crop genetic engineering can significantly pace up the development of genetically improved varieties with enhanced yield, nutrition and tolerance to biotic and abiotic stresses. Genetically modified (GM) crops can act as powerful complement to the crops produced by laborious and time consuming conventional breeding methods to meet the worldwide demand for quality foods. GM crops can help fight malnutrition due to enhanced yield, nutritional quality and increased resistance to various biotic and abiotic stresses. However, several biosafety issues and public concerns are associated with cultivation of GM crops developed by transgenesis, i.e., introduction of genes from distantly related organism. To meet these concerns, researchers have developed alternative concepts of cisgenesis and intragenesis which involve transformation of plants with genetic material derived from the species itself or from closely related species capable of sexual hybridization, respectively. Recombinase technology aimed at site-specific integration of transgene can help to overcome limitations of traditional genetic engineering methods based on random integration of multiple copy of transgene into plant genome leading to gene silencing and unpredictable expression pattern. Besides, recently developed technology of genome editing using engineered nucleases, permit the modification or mutation of genes of interest without involving foreign DNA, and as a result, plants developed with this technology might be considered as non-transgenic genetically altered plants. This would open the doors for the development and commercialization of transgenic plants with superior phenotypes even in countries where GM crops are poorly accepted. This review is an attempt to summarize various past achievements of GM technology in crop improvement, recent progress and new advances in the field to develop improved varieties aimed for better consumer acceptance.

Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

Directory of Open Access Journals (Sweden)

Huaqiang Chu

2013-09-01

Full Text Available The application of low pressure membranes (microfiltration/ultrafiltration has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM. This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.. Perspectives of further research are also discussed.

Genetic and non-iodine-related factors in the aetiology of nodular goitre.

Science.gov (United States)

Knudsen, Nils; Brix, Thomas Heiberg

2014-08-01

Genetic and a large number of environmental non-iodine-related factors play a role in the cause of nodular goitre. Most evidence for the influence of genetic and environmental factors in the cause of goitre is from cross-sectional, population-based studies. Only a few studies have included prospective data on risk factors for nodular goitre, although few prospective data are available on the effect of iodine and tobacco smoking on goitre development. Goitre is not one single phenotype. Many epidemiological studies do not distinguish diffuse from nodular goitre, as the investigated parameter is often thyroid volume or frequency with increased thyroid volume. Moreover, information on the presence and effect of gene-environment, gene-gene, and environment-environment effect modifications is limited. Thus, firm conclusions about the relative contributions and causality of the investigated risk factors should be made with caution. Smoking seems to be an established risk factor for nodular goitre, possibly with effect modification from iodine intake, as the risk associated with smoking is smaller or absent in areas with sufficient iodine intake. The use of oral contraceptives might have protective effects against goitre, and childbirth is an increased risk factor for goitre in areas with non-optimal iodine intake. Insulin resistance is a recently investigated risk factor, and the risk of goitre may be reversible with metformin treatment. Iodine remains the major environmental risk factor for nodular goitre. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stochastic stabilization of phenotypic States: the genetic bistable switch as a case study.

Science.gov (United States)

Weber, Marc; Buceta, Javier

2013-01-01

We study by means of analytical calculation and stochastic simulations how intrinsic noise modifies the bifurcation diagram of gene regulatory processes that can be effectively described by the Langevin formalism. In a general context, our study raises the intriguing question of how biochemical fluctuations redesign the epigenetic landscape in differentiation processes. We have applied our findings to a general class of regulatory processes that includes the simplest case that displays a bistable behavior and hence phenotypic variability: the genetic auto-activating switch. Thus, we explain why and how the noise promotes the stability of the low-state phenotype of the switch and show that the bistable region is extended when increasing the intensity of the fluctuations. This phenomenology is found in a simple one-dimensional model of the genetic switch as well as in a more detailed model that takes into account the binding of the protein to the promoter region. Altogether, we prescribe the analytical means to understand and quantify the noise-induced modifications of the bifurcation points for a general class of regulatory processes where the genetic bistable switch is included.

Endothelial cell repopulation after stenting determines in-stent neointima formation: effects of bare-metal vs. drug-eluting stents and genetic endothelial cell modification.

Science.gov (United States)

Douglas, Gillian; Van Kampen, Erik; Hale, Ashley B; McNeill, Eileen; Patel, Jyoti; Crabtree, Mark J; Ali, Ziad; Hoerr, Robert A; Alp, Nicholas J; Channon, Keith M

2013-11-01

Understanding endothelial cell repopulation post-stenting and how this modulates in-stent restenosis is critical to improving arterial healing post-stenting. We used a novel murine stent model to investigate endothelial cell repopulation post-stenting, comparing the response of drug-eluting stents with a primary genetic modification to improve endothelial cell function. Endothelial cell repopulation was assessed en face in stented arteries in ApoE(-/-) mice with endothelial-specific LacZ expression. Stent deployment resulted in near-complete denudation of endothelium, but was followed by endothelial cell repopulation, by cells originating from both bone marrow-derived endothelial progenitor cells and from the adjacent vasculature. Paclitaxel-eluting stents reduced neointima formation (0.423 ± 0.065 vs. 0.240 ± 0.040 mm(2), P = 0.038), but decreased endothelial cell repopulation (238 ± 17 vs. 154 ± 22 nuclei/mm(2), P = 0.018), despite complete strut coverage. To test the effects of selectively improving endothelial cell function, we used transgenic mice with endothelial-specific overexpression of GTP-cyclohydrolase 1 (GCH-Tg) as a model of enhanced endothelial cell function and increased NO production. GCH-Tg ApoE(-/-) mice had less neointima formation compared with ApoE(-/-) littermates (0.52 ± 0.08 vs. 0.26 ± 0.09 mm(2), P = 0.039). In contrast to paclitaxel-eluting stents, reduced neointima formation in GCH-Tg mice was accompanied by increased endothelial cell coverage (156 ± 17 vs. 209 ± 23 nuclei/mm(2), P = 0.043). Drug-eluting stents reduce not only neointima formation but also endothelial cell repopulation, independent of strut coverage. In contrast, selective targeting of endothelial cell function is sufficient to improve endothelial cell repopulation and reduce neointima formation. Targeting endothelial cell function is a rational therapeutic strategy to improve vascular healing and decrease neointima formation after stenting.

Modification of JRR-4 based on safety evaluation

Energy Technology Data Exchange (ETDEWEB)

Izumo, Hironobu; Nakajima, Teruo; Funayama, Yoshiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-10-01

Since the first criticality was achieved on January 28, 1965, JRR-4 has been operated safely until on January 12, 1996. The modification of JRR-4 was planned according to the framework of reduced enrichment on research reactor program. The modification was designed based on the several national safety guides. JRR-4 has some modifications of facilities to satisfy the guides and guides criteria. (author)

Mapping Base Modifications in DNA by Transverse-Current Sequencing

Science.gov (United States)

Alvarez, Jose R.; Skachkov, Dmitry; Massey, Steven E.; Kalitsov, Alan; Velev, Julian P.

2018-02-01

Sequencing DNA modifications and lesions, such as methylation of cytosine and oxidation of guanine, is even more important and challenging than sequencing the genome itself. The traditional methods for detecting DNA modifications are either insensitive to these modifications or require additional processing steps to identify a particular type of modification. Transverse-current sequencing in nanopores can potentially identify the canonical bases and base modifications in the same run. In this work, we demonstrate that the most common DNA epigenetic modifications and lesions can be detected with any predefined accuracy based on their tunneling current signature. Our results are based on simulations of the nanopore tunneling current through DNA molecules, calculated using nonequilibrium electron-transport methodology within an effective multiorbital model derived from first-principles calculations, followed by a base-calling algorithm accounting for neighbor current-current correlations. This methodology can be integrated with existing experimental techniques to improve base-calling fidelity.

Surface modification of polyester biomaterials for tissue engineering

International Nuclear Information System (INIS)

Jiao Yanpeng; Cui Fuzhai

2007-01-01

Surfaces play an important role in a biological system for most biological reactions occurring at surfaces and interfaces. The development of biomaterials for tissue engineering is to create perfect surfaces which can provoke specific cellular responses and direct new tissue regeneration. The improvement in biocompatibility of biomaterials for tissue engineering by directed surface modification is an important contribution to biomaterials development. Among many biomaterials used for tissue engineering, polyesters have been well documented for their excellent biodegradability, biocompatibility and nontoxicity. However, poor hydrophilicity and the lack of natural recognition sites on the surface of polyesters have greatly limited their further application in the tissue engineering field. Therefore, how to introduce functional groups or molecules to polyester surfaces, which ideally adjust cell/tissue biological functions, becomes more and more important. In this review, recent advances in polyester surface modification and their applications are reviewed. The development of new technologies or methods used to modify polyester surfaces for developing their biocompatibility is introduced. The results of polyester surface modifications by surface morphological modification, surface chemical group/charge modification, surface biomacromolecule modification and so on are reported in detail. Modified surface properties of polyesters directly related to in vitro/vivo biological performances are presented as well, such as protein adsorption, cell attachment and growth and tissue response. Lastly, the prospect of polyester surface modification is discussed, especially the current conception of biomimetic and molecular recognition. (topical review)

Ethics of genetic testing and research in sport: a position statement from the Australian Institute of Sport.

Science.gov (United States)

Vlahovich, Nicole; Fricker, Peter A; Brown, Matthew A; Hughes, David

2017-01-01

As Australia's peak high-performance sport agency, the Australian Institute of Sport (AIS) has developed this position statement to address the implications of recent advances in the field of genetics and the ramifications for the health and well-being of athletes. Genetic testing has proven of value in the practice of clinical medicine. There are, however, currently no scientific grounds for the use of genetic testing for athletic performance improvement, sport selection or talent identification. Athletes and coaches should be discouraged from using direct-to-consumer genetic testing because of its lack of validation and replicability and the lack of involvement of a medical practitioner in the process. The transfer of genetic material or genetic modification of cells for performance enhancement is gene doping and should not be used on athletes. There are, however, valid roles for genetic research and the AIS supports genetic research which aims to enhance understanding of athlete susceptibility to injury or illness. Genetic research is only to be conducted after careful consideration of a range of ethical concerns which include the provision of adequate informed consent. The AIS is committed to providing leadership in delivering an ethical framework that protects the well-being of athletes and the integrity of sport, in the rapidly changing world of genomic science. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Lentiviral vector mediated modification of mesenchymal stem cells & enhanced survival in an in vitro model of ischaemia.

LENUS (Irish Health Repository)

McGinley, Lisa

2012-01-31

INTRODUCTION: A combination of gene and cell therapies has the potential to significantly enhance the therapeutic value of mesenchymal stem cells (MSCs). The development of efficient gene delivery methods is essential if MSCs are to be of benefit using such an approach. Achieving high levels of transgene expression for the required period of time, without adversely affecting cell viability and differentiation capacity, is crucial. In the present study, we investigate lentiviral vector-mediated genetic modification of rat bone-marrow derived MSCs and examine any functional effect of such genetic modification in an in vitro model of ischaemia. METHODS: Transduction efficiency and transgene persistence of second and third generation rHIV-1 based lentiviral vectors were tested using reporter gene constructs. Use of the rHIV-pWPT-EF1-alpha-GFP-W vector was optimised in terms of dose, toxicity, cell species, and storage. The in vivo condition of ischaemia was modelled in vitro by separation into its associated constituent parts i.e. hypoxia, serum and glucose deprivation, in which the effect of therapeutic gene over-expression on MSC survival was investigated. RESULTS: The second generation lentiviral vector rHIV-pWPT-EF1-alpha-GFP-W, was the most efficient and provided the most durable transgene expression of the vectors tested. Transduction with this vector did not adversely affect MSC morphology, viability or differentiation potential, and transgene expression levels were unaffected by cryopreservation of transduced cells. Over-expression of HSP70 resulted in enhanced MSC survival and increased resistance to apoptosis in conditions of hypoxia and ischaemia. MSC differentiation capacity was significantly reduced after oxygen deprivation, but was preserved with HSP70 over-expression. CONCLUSIONS: Collectively, these data validate the use of lentiviral vectors for efficient in vitro gene delivery to MSCs and suggest that lentiviral vector transduction can facilitate

Lentiviral vector mediated modification of mesenchymal stem cells & enhanced survival in an in vitro model of ischaemia

LENUS (Irish Health Repository)

McGinley, Lisa

2011-03-07

Abstract Introduction A combination of gene and cell therapies has the potential to significantly enhance the therapeutic value of mesenchymal stem cells (MSCs). The development of efficient gene delivery methods is essential if MSCs are to be of benefit using such an approach. Achieving high levels of transgene expression for the required period of time, without adversely affecting cell viability and differentiation capacity, is crucial. In the present study, we investigate lentiviral vector-mediated genetic modification of rat bone-marrow derived MSCs and examine any functional effect of such genetic modification in an in vitro model of ischaemia. Methods Transduction efficiency and transgene persistence of second and third generation rHIV-1 based lentiviral vectors were tested using reporter gene constructs. Use of the rHIV-pWPT-EF1-α-GFP-W vector was optimised in terms of dose, toxicity, cell species, and storage. The in vivo condition of ischaemia was modelled in vitro by separation into its associated constituent parts i.e. hypoxia, serum and glucose deprivation, in which the effect of therapeutic gene over-expression on MSC survival was investigated. Results The second generation lentiviral vector rHIV-pWPT-EF1-α-GFP-W, was the most efficient and provided the most durable transgene expression of the vectors tested. Transduction with this vector did not adversely affect MSC morphology, viability or differentiation potential, and transgene expression levels were unaffected by cryopreservation of transduced cells. Over-expression of HSP70 resulted in enhanced MSC survival and increased resistance to apoptosis in conditions of hypoxia and ischaemia. MSC differentiation capacity was significantly reduced after oxygen deprivation, but was preserved with HSP70 over-expression. Conclusions Collectively, these data validate the use of lentiviral vectors for efficient in vitro gene delivery to MSCs and suggest that lentiviral vector transduction can facilitate

Repair-modification of radiodamaged genes

International Nuclear Information System (INIS)

Volpe, P.; Institute of Experimental Medicine, Rome; Eremenko, T.

1995-01-01

It is proposed that through repair-modification, the modified base 5mC may have facilitated the divergent evolution of coding (hypomethylated exon) and uncoding (hypermethylated promoter and intron) sequences in eukaryotic genes. The radioinduced repair patches appearing in regions lacking 5mC are fully reconstructed by excision-repair, whereas those appearing in regions containing 5mC are incompletely reconstructed by this conventional mechanism. Such a second class of repair patches may, however, become fully reconstructed, in the S phase, by repair-modification. In fact, while DNA polymerase β - which is a key enzyme of excision-repair - is active through the whole interphase. DNA methylase - which is responsible for post-synthetic DNA modification - is essentially active in S. Uncoupling of these two enzyme systems, outside S, might explain why in unsynchronised cells repair patches of non-replicating strands are hypomethylated when compared with specific methylation of replicating strands. In other words, excision-repair would always be able to re-establish the primary ATGC language of both damaged unmethylated and methylated regions, while repair-modification would be able to re-establish the modified ATGC(5mC) language of the damaged methylated regions, only in S, but not in G 1 or G 2 . In these two phases, when DNA methylation is inversely correlated with pre-mRNA transcription (as in the case of many tissue-specific genes), such demethylation might induce a silent transcriptional unit to become active. (Author)

A new methodology to obtain wine yeast strains overproducing mannoproteins.

Science.gov (United States)

Quirós, Manuel; Gonzalez-Ramos, Daniel; Tabera, Laura; Gonzalez, Ramon

2010-04-30

Yeast mannoproteins are highly glycosylated proteins that are covalently bound to the beta-1,3-glucan present in the yeast cell wall. Among their outstanding enological properties, yeast mannoproteins contribute to several aspects of wine quality by protecting against protein haze, reducing astringency, retaining aroma compounds and stimulating growth of lactic-acid bacteria. The development of a non-recombinant method to obtain enological yeast strains overproducing mannoproteins would therefore be very useful. Our previous experience on the genetic determinants of the release of these molecules by Saccharomyces cerevisiae has allowed us to propose a new methodology to isolate and characterize wine yeast that overproduce mannoproteins. The described methodology is based on the resistance of the killer 9 toxin produced by Williopsis saturnus, a feature linked to an altered biogenesis of the yeast cell wall. Copyright 2010 Elsevier B.V. All rights reserved.

DNA modification by alkylating compounds

Energy Technology Data Exchange (ETDEWEB)

Kruglyakova, E.E.

1985-09-01

Results are given for research on the physico-chemical properties of alkylating compounds - nitroso alkyl ureas (NAU) which possess a broad spectrum of biological activity, such as mutagenic, carcinogenic, and anti-tumor action that is due to the alkylation and carbamoylation of DNA as well as other cellular components. Identified chemical products of NAU interaction with DNA and its components are cited. Structural conversions of a DNA macromolecule resulting from its chemical modification are examined. NAU are used to discuss possible biological consequences of DNA modification. 148 references.

Corrosion principles and surface modification

International Nuclear Information System (INIS)

Kruger, J.

1982-01-01

This chapter examines the important strategies provided by the newer ideas of corrosion science and engineering that surface modification techniques must utilize to help prevent corrosion, especially the most damaging kind of aqueous corrosion, localized corrosion. Provides a brief introduction to the principles underlying the phenomenon of corrosion in order to use them to discuss surface modification strategies to combat corrosion. Discusses the electrochemistry of corrosion; the thermodynamics of corrosion; the kinetics of corrosion; thermodynamic strategies; and kinetic strategies (formation of more protective passive films; resistance to breakdown; ductility; repassivation)

Meiotic transmission of Drosophila pseudoobscura chromosomal arrangements.

Directory of Open Access Journals (Sweden)

Richard P Meisel

Full Text Available Drosophila pseudoobscura harbors a rich gene arrangement polymorphism on the third chromosome generated by a series of overlapping paracentric inversions. The arrangements suppress recombination in heterokaryotypic individuals, which allows for the selective maintenance of coadapted gene complexes. Previous mapping experiments used to determine the degree to which recombination is suppressed in gene arrangement heterozygotes produced non-recombinant progeny in non-Mendelian ratios. The deviations from Mendelian expectations could be the result of viability differences between wild and mutant chromosomes, meiotic drive because of achiasmate pairing of homologues in heterokaryotypic females during meiosis, or a combination of both mechanisms. The possibility that the frequencies of the chromosomal arrangements in natural populations are affected by mechanisms other than adaptive selection led us to consider these hypotheses. We performed reciprocal crosses involving both heterozygous males and females to determine if the frequency of the non-recombinant progeny deviates significantly from Mendelian expectations and if the frequencies deviate between reciprocal crosses. We failed to observe non-Mendelian ratios in multiple crosses, and the frequency of the non-recombinant classes differed in only one of five pairs of reciprocal crosses despite sufficient power to detect these differences in all crosses. Our results indicate that deviations from Mendelian expectations in recombination experiments involving the D. pseudoobscura inversion system are most likely due to fitness differences of gene arrangement karyotypes in different environments.

A Novel Tool for Microbial Genome Editing Using the Restriction-Modification System.

Science.gov (United States)

Bai, Hua; Deng, Aihua; Liu, Shuwen; Cui, Di; Qiu, Qidi; Wang, Laiyou; Yang, Zhao; Wu, Jie; Shang, Xiuling; Zhang, Yun; Wen, Tingyi

2018-01-19

Scarless genetic manipulation of genomes is an essential tool for biological research. The restriction-modification (R-M) system is a defense system in bacteria that protects against invading genomes on the basis of its ability to distinguish foreign DNA from self DNA. Here, we designed an R-M system-mediated genome editing (RMGE) technique for scarless genetic manipulation in different microorganisms. For bacteria with Type IV REase, an RMGE technique using the inducible DNA methyltransferase gene, bceSIIM (RMGE-bceSIIM), as the counter-selection cassette was developed to edit the genome of Escherichia coli. For bacteria without Type IV REase, an RMGE technique based on a restriction endonuclease (RMGE-mcrA) was established in Bacillus subtilis. These techniques were successfully used for gene deletion and replacement with nearly 100% counter-selection efficiencies, which were higher and more stable compared to conventional methods. Furthermore, precise point mutation without limiting sites was achieved in E. coli using RMGE-bceSIIM to introduce a single base mutation of A128C into the rpsL gene. In addition, the RMGE-mcrA technique was applied to delete the CAN1 gene in Saccharomyces cerevisiae DAY414 with 100% counter-selection efficiency. The effectiveness of the RMGE technique in E. coli, B. subtilis, and S. cerevisiae suggests the potential universal usefulness of this technique for microbial genome manipulation.

Multiple Posttranslational Modifications of Leptospira biflexa Proteins as Revealed by Proteomic Analysis.

Science.gov (United States)

Stewart, Philip E; Carroll, James A; Olano, L Rennee; Sturdevant, Daniel E; Rosa, Patricia A

2016-02-15

The saprophyte Leptospira biflexa is an excellent model for studying the physiology of the medically important Leptospira genus, the pathogenic members of which are more recalcitrant to genetic manipulation and have significantly slower in vitro growth. However, relatively little is known regarding the proteome of L. biflexa, limiting its utility as a model for some studies. Therefore, we have generated a proteomic map of both soluble and membrane-associated proteins of L. biflexa during exponential growth and in stationary phase. Using these data, we identified abundantly produced proteins in each cellular fraction and quantified the transcript levels from a subset of these genes using quantitative reverse transcription-PCR (RT-PCR). These proteins should prove useful as cellular markers and as controls for gene expression studies. We also observed a significant number of L. biflexa membrane-associated proteins with multiple isoforms, each having unique isoelectric focusing points. L. biflexa cell lysates were examined for several posttranslational modifications suggested by the protein patterns. Methylation and acetylation of lysine residues were predominately observed in the proteins of the membrane-associated fraction, while phosphorylation was detected mainly among soluble proteins. These three posttranslational modification systems appear to be conserved between the free-living species L. biflexa and the pathogenic species Leptospira interrogans, suggesting an important physiological advantage despite the varied life cycles of the different species. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

MODIFICATION OF SURFACE KONDENSITSIONNYH AEROSOLS WELDING AND METALLURGICHESKIH PRODUCTIONS

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A. A. Ennan

2016-04-01

Full Text Available Chemical modification of surface kondensitsionnyh aerosols (KA which formation when heat treatment metals (process of weld, foundry processes with application chlorosilanes are suggested. Adsorbtion vapor of water on modification powders KA decreases and changes in varies from modifier and conditions modification are setted.

12 CFR 725.21 - Modification of agreements.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Modification of agreements. 725.21 Section 725.21 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.21 Modification of agreements. The...

Surface Modification of Biomaterials: A Quest for Blood Compatibility

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Achala de Mel

2012-01-01

Full Text Available Cardiovascular implants must resist thrombosis and intimal hyperplasia to maintain patency. These implants when in contact with blood face a challenge to oppose the natural coagulation process that becomes activated. Surface protein adsorption and their relevant 3D confirmation greatly determine the degree of blood compatibility. A great deal of research efforts are attributed towards realising such a surface, which comprise of a range of methods on surface modification. Surface modification methods can be broadly categorized as physicochemical modifications and biological modifications. These modifications aim to modulate platelet responses directly through modulation of thrombogenic proteins or by inducing antithrombogenic biomolecules that can be biofunctionalised onto surfaces or through inducing an active endothelium. Nanotechnology is recognising a great role in such surface modification of cardiovascular implants through biofunctionalisation of polymers and peptides in nanocomposites and through nanofabrication of polymers which will pave the way for finding a closer blood match through haemostasis when developing cardiovascular implants with a greater degree of patency.

The Pleiotropic Phenotype of Apc Mutations in the Mouse: Allele Specificity and Effects of the Genetic Background

Science.gov (United States)

Halberg, Richard B.; Chen, Xiaodi; Amos-Landgraf, James M.; White, Alanna; Rasmussen, Kristin; Clipson, Linda; Pasch, Cheri; Sullivan, Ruth; Pitot, Henry C.; Dove, William F.

2008-01-01

Familial adenomatous polyposis (FAP) is a human cancer syndrome characterized by the development of hundreds to thousands of colonic polyps and extracolonic lesions including desmoid fibromas, osteomas, epidermoid cysts, and congenital hypertrophy of the pigmented retinal epithelium. Afflicted individuals are heterozygous for mutations in the APC gene. Detailed investigations of mice heterozygous for mutations in the ortholog Apc have shown that other genetic factors strongly influence the phenotype. Here we report qualitative and quantitative modifications of the phenotype of Apc mutants as a function of three genetic variables: Apc allele, p53 allele, and genetic background. We have found major differences between the Apc alleles Min and 1638N in multiplicity and regionality of intestinal tumors, as well as in incidence of extracolonic lesions. By contrast, Min mice homozygous for either of two different knockout alleles of p53 show similar phenotypic effects. These studies illustrate the classic principle that functional genetics is enriched by assessing penetrance and expressivity with allelic series. The mouse permits study of an allelic gene series on multiple genetic backgrounds, thereby leading to a better understanding of gene action in a range of biological processes. PMID:18723878

Trophic interaction modifications: an empirical and theoretical framework.

Science.gov (United States)

Terry, J Christopher D; Morris, Rebecca J; Bonsall, Michael B

2017-10-01

Consumer-resource interactions are often influenced by other species in the community. At present these 'trophic interaction modifications' are rarely included in ecological models despite demonstrations that they can drive system dynamics. Here, we advocate and extend an approach that has the potential to unite and represent this key group of non-trophic interactions by emphasising the change to trophic interactions induced by modifying species. We highlight the opportunities this approach brings in comparison to frameworks that coerce trophic interaction modifications into pairwise relationships. To establish common frames of reference and explore the value of the approach, we set out a range of metrics for the 'strength' of an interaction modification which incorporate increasing levels of contextual information about the system. Through demonstrations in three-species model systems, we establish that these metrics capture complimentary aspects of interaction modifications. We show how the approach can be used in a range of empirical contexts; we identify as specific gaps in current understanding experiments with multiple levels of modifier species and the distributions of modifications in networks. The trophic interaction modification approach we propose can motivate and unite empirical and theoretical studies of system dynamics, providing a route to confront ecological complexity. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Drug delivery from hydrophobic-modified mesoporous silicas: Control via modification level and site-selective modification

International Nuclear Information System (INIS)

Tang Qunli; Chen Yuxi; Chen Jianghua; Li Jin; Xu Yao; Wu Dong; Sun Yuhan

2010-01-01

Dimethylsilyl (DMS) modified mesoporous silicas were successfully prepared via co-condensation and post-grafting modification methods. The post-grafting modification was carried out by the reaction of the as-synthesized MCM-41 material (before CTAB removal) with diethoxydimethylsinale (DEDMS). N 2 adsorption-desorption and 29 Si MAS NMR characterization demonstrated that different amount of DMS groups were successfully incorporated into the co-condensation modified samples, and the functional DMS groups were placed selectively on the pore openings and external pore surfaces in the post-grafting modified samples. Subsequently, the controlled drug delivery properties from the resulting DMS-modified mesoporous silicas were investigated in detail. The drug adsorption experiments showed that the adsorption capacities were mainly depended on the content of silanol group (CSG) in the corresponding carriers. The in vitro tests exhibited that the incorporation of DMS groups greatly retarded the ibuprofen release rate. Moreover, the ibuprofen release profiles could be well modulated by varying DMS modification levels and site-selective distribution of functional groups in mesoporous carriers. - The distribution of DMS groups on the pore surfaces of the mesostructures strongly affects the drug release rate. The P-M41-1 and the P-M41-2 possess the close DMS modification levels as the C-M41-10, but the ibuprofen release rates from the P-M41-1 and P-M41-2 are much slower than that from the C-M41-10.

Medium Modifications of Hadrons in Photon Induced Reactions

International Nuclear Information System (INIS)

Schadmand, S.

2004-01-01

Indications for in-medium modifications of hadron properties are reported from photoabsorption and meson production experiments. Strong medium modifications are observed in inclusive photoabsorption experiments and theoretical models investigate the in-medium dynamics of baryon resonances and their coupling to mesons. Recent experiments study the in-medium behavior of scalar and vector mesons where theoretical models expect in-medium modifications of the meson spectral functions that might be connected to partial restoration of chiral symmetry

Protein covalent modification by biologically active quinones

Directory of Open Access Journals (Sweden)

MIROSLAV J. GASIC

2004-11-01

Full Text Available The avarone/avarol quinone/hydroquinone couple shows considerable antitumor activity. In this work, covalent modification of b-lactoglobulin by avarone and its derivatives as well as by the synthetic steroidal quinone 2,5(10-estradiene-1,4,17-trione and its derivatives were studied. The techniques for studying chemical modification of b-lactoglobulin by quinones were: UV/Vis spectrophotometry, SDS PAGE and isoelectrofocusing. SDS PAGE results suggest that polymerization of the protein occurs. It could be seen that the protein of 18 kD gives the bands of 20 kD, 36 kD, 40 kD, 45 kD, 64 kD and 128 kD depending on modification agent. The shift of the pI of the protein (5.4 upon modification toward lower values (from pI 5.0 to 5.3 indicated that lysine amino groups are the principal site of the reaction of b-lactoglobulin with the quinones.

A proposed impact assessment method for genetically modified plants (AS-GMP Method)

International Nuclear Information System (INIS)

Jesus-Hitzschky, Katia Regina Evaristo de; Silveira, Jose Maria F.J. da

2009-01-01

An essential step in the development of products based on biotechnology is an assessment of their potential economic impacts and safety, including an evaluation of the potential impact of transgenic crops and practices related to their cultivation on the environment and human or animal health. The purpose of this paper is to provide an assessment method to evaluate the impact of biotechnologies that uses quantifiable parameters and allows a comparative analysis between conventional technology and technologies using GMOs. This paper introduces a method to perform an impact analysis associated with the commercial release and use of genetically modified plants, the Assessment System GMP Method. The assessment is performed through indicators that are arranged according to their dimension criterion likewise: environmental, economic, social, capability and institutional approach. To perform an accurate evaluation of the GMP specific indicators related to genetic modification are grouped in common fields: genetic insert features, GM plant features, gene flow, food/feed field, introduction of the GMP, unexpected occurrences and specific indicators. The novelty is the possibility to include specific parameters to the biotechnology under assessment. In this case by case analysis the factors of moderation and the indexes are parameterized to perform an available assessment.

The ethics of molecular memory modification.

Science.gov (United States)

Hui, Katrina; Fisher, Carl E

2015-07-01

Novel molecular interventions have recently shown the potential to erase, enhance and alter specific long-term memories. Unique features of this form of memory modification call for a close examination of its possible applications. While there have been discussions of the ethics of memory modification in the literature, molecular memory modification (MMM) can provide special insights. Previously raised ethical concerns regarding memory enhancement, such as safety issues, the 'duty to remember', selfhood and personal identity, require re-evaluation in light of MMM. As a technology that exploits the brain's updating processes, MMM helps correct the common misconception that memory is a static entity by demonstrating how memory is plastic and subject to revision even in the absence of external manipulation. Furthermore, while putatively safer than other speculative technologies because of its high specificity, MMM raises notable safety issues, including potential insidious effects on the agent's emotions and personal identity. Nonetheless, MMM possesses characteristics of a more permissible form of modification, not only because it is theoretically safer, but because its unique mechanism of action requires a heightened level of cooperation from the agent. Discussions of memory modification must consider the specific mechanisms of action, which can alter the weight and relevance of various ethical concerns. MMM also highlights the need for conceptual accuracy regarding the term 'enhancement'; this umbrella term will have to be differentiated as new technologies are applied to a widening array of purposes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Safety improvement plant modifications at Forsmark 3, 1986-1995

Energy Technology Data Exchange (ETDEWEB)

Kjellander, M. [Kaernkraftsaekerhet och utbildning, Nykoeping (Sweden)

1998-10-01

All important plant modifications implemented in safety-related equipment or software at Forsmark 3 are compiled in this report. The report covers the period from the start of commercial operation in 1985 up to and including 1995. The plant modifications, which were carried out by different suppliers during the guarantee period, are not included in the report since they have not been administered by the Forsmark organisation. The report contains references to relevant modification notices and to files and file divider numbers. These data refer to the Safety Department central archives. The report is based on Forsmark 3 Technical Specifications (STF) which means that Chapter 3 is divided into the same sections as in the STF. Modifications, which cannot be directly attributed to any specific STF chapter, and major modifications are described separately

Chemical modification of b-lactoglobulin by quinones

Directory of Open Access Journals (Sweden)

DUSAN SLADIC

2003-05-01

Full Text Available The avarone/avarol quinone/hydroquinone couple, as well as their derivatives show considerable antitumor activity. In this work, covalent modifications of b-lactoglobulin, isolated from cow milk, by avarone, its model compound 2-tert-butyl-1,4-benzoquinone, and several of their alkylthio derivatives were studied. The techniques applied for assaying the modifications were: UV/VIS spectrophotometry, SDS PAGE and isoelectrofocusing. The results of the SDS PAGE suggest that polymerisation of the protein occurs. The shift of the pI of the protein upon modification toward lower values indicates that lysine amino groups are the principal site of the reaction of b-lactoglobulin with the quinones.

OCCASIONAL ADNOMINAL IDIOM MODIFICATION - A COGNITIVE LINGUISTIC APPROACH

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Andreas Langlotz

2006-06-01

Full Text Available occasional Adnominal Idiom Modification - A Cognitive Linguistic Approach From a cognitive-linguistic perspective, this paper explores alternative types of adnoniinal modification in occasional variants of English verbal idioms. Being discussed against data extracted from the British National Corpiis (BNC, the model claims that in idioni-production idiomatic constructions are activated as complex linguistic schemas to code a context-specific target-conceptualisation. Adnominal pre- and postmodifications are one specific form of creative alteration to adapt the idiom for this purpose. Semantically, idiom-interna1 NPextension is not a uniforni process. It is necessary to distinguish two systematic types of adnominal modification: external and internal modification (Ernst 1981. While external NPmodification has adverbial function, ¡.e. it modifies the idiom as a unit, internal modification directly applies to the head-noun and thus depends on the degree of motivation and analysability of a given idiom. Following the cognitive-linguistic framework, these dimensions of idiom-transparency result from the language user's ability to remotivate the bipartite semantic structure by conceptual metaphors and metonymies.

Development of FOCUS-GC: Framework for Outcomes of Clinical Communication Services in Genetic Counseling.

Science.gov (United States)

Cragun, Deborah; Zierhut, Heather

2018-02-01

Conceptual frameworks bring together existing theories and models in order to identify, consolidate, and fill in gaps between theory, practice, and evidence. Given the vast number of possible outcomes that could be studied in genetic counseling, a framework for organizing outcomes and postulating relationships between communication services and genetic counseling outcomes was sought. Through an iterative approach involving literature review, thematic analysis, and consolidation, outcomes and processes were categorized to create and define components of a conceptual framework. The final product, "Framework for Outcomes of Clinical commUnication Services" (FOCUS) contains the following domains: communication strategy; communication process measures; patient care experience, patient changes, patient health; and family changes. A website was created to allow easier access and ongoing modifications to the framework. In addition, a step-by-step guide and two examples were created to show flexibility in how the framework can be used. FOCUS may help in conceptualizing, organizing and summarizing outcomes research related to risk communication and counseling in genetic service delivery as well as other healthcare settings.

42 CFR 412.72 - Modification of base-year costs.

Science.gov (United States)

2010-10-01

... 42 Public Health 2 2010-10-01 2010-10-01 false Modification of base-year costs. 412.72 Section 412... Modification of base-year costs. (a) Bases for modification of base-year costs. Base-year costs as determined... before November 16, 1983 has until November 15, 1983 to request its intermediary to reestimate its base...

Genetic classes and genetic categories : Protecting genetic groups through data protection law

NARCIS (Netherlands)

Hallinan, Dara; de Hert, Paul; Taylor, L.; Floridi, L.; van der Sloot, B.

2017-01-01

Each person shares genetic code with others. Thus, one individual’s genome can reveal information about other individuals. When multiple individuals share aspects of genetic architecture, they form a ‘genetic group’. From a social and legal perspective, two types of genetic group exist: Those which

Plant Genetic Resources: Selected Issues from Genetic Erosion to Genetic Engineering

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Karl Hammer

2008-04-01

Full Text Available Plant Genetic Resources (PGR continue to play an important role in the development of agriculture. The following aspects receive a special consideration:1. Definition. The term was coined in 1970. The genepool concept served as an important tool in the further development. Different approaches are discussed.2. Values of Genetic Resources. A short introduction is highlighting this problem and stressing the economic usfulness of PGR.3. Genetic Erosion. Already observed by E. Baur in 1914, this is now a key issue within PGR. The case studies cited include Ethiopia, Italy, China, S Korea, Greece and S. Africa. Modern approaches concentrate on allelic changes in varieties over time but neglect the landraces. The causes and consequences of genetic erosion are discussed.4. Genetic Resources Conservation. Because of genetic erosion there is a need for conservation. PGR should be consigned to the appropriate method of conservation (ex situ, in situ, on-farm according to the scientific basis of biodiversity (genetic diversity, species diversity, ecosystem diversity and the evolutionary status of plants (cultivated plants, weeds, related wild plants (crop wild relatives.5. GMO. The impact of genetically engineered plants on genetic diversity is discussed.6. The Conclusions and Recommendations stress the importance of PGR. Their conservation and use are urgent necessities for the present development and future survival of mankind.

Tribological effects of polymer surface modification through plastic

Indian Academy of Sciences (India)