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1

Genomewide transcriptional changes associated with genetic alterations and nutritional supplementation affecting tryptophan metabolism in Bacillus subtilis  

PubMed Central

DNA microarrays comprising ?95% of the Bacillus subtilis annotated protein coding ORFs were deployed to generate a series of snapshots of genomewide transcriptional changes that occur when cells are grown under various conditions that are expected to increase or decrease transcription of the trp operon segment of the aromatic supraoperon. Comparisons of global expression patterns were made between cells grown in the presence of indole acrylic acid, a specific inhibitor of tRNATrp charging; cells deficient in expression of the mtrB gene, which encodes the tryptophan-activated negative regulatory protein, TRAP; WT cells grown in the presence or absence of two or three of the aromatic amino acids; and cells harboring a tryptophanyl tRNA synthetase mutation conferring temperature-sensitive tryptophan-dependent growth. Our findings validate expected responses of the tryptophan biosynthetic genes and presumed regulatory interrelationships between genes in the different aromatic amino acid pathways and the histidine biosynthetic pathway. Using a combination of supervised and unsupervised statistical methods we identified ?100 genes whose expression profiles were closely correlated with those of the genes in the trp operon. This finding suggests that expression of these genes is influenced directly or indirectly by regulatory events that affect or are a consequence of altered tryptophan metabolism.

Berka, Randy M.; Cui, Xianju; Yanofsky, Charles

2003-01-01

2

Epigenetic drivers of genetic alterations.  

PubMed

DNA methylation plays a key role in the silencing of cancer-related genes, thereby affecting numerous cellular processes, including the cell cycle checkpoint, apoptosis, signal transduction, cell adhesion, and angiogenesis. DNA methylation also affects the expression of genes involved in maintaining the integrity of the genome through DNA repair and detoxification of reactive oxygen species. Here, we discuss how epigenetic changes lead to genetic alterations, including microsatellite instability and nucleotide and chromosomal alterations. Epigenetic inactivation of hMLH1 is a major cause of microsatellite instability in sporadic colorectal cancers, and germline epimutation of hMLH1 and hMSH2 is a cause of hereditary nonpolyposis colorectal cancers, which do not show mutation of mismatch repair genes. Epigenetic inactivation of MGMT is often associated with G:C-to-A:T mutations in K-ras and p53, while epigenetic inactivation of BRCA1, WRN, FANCF, and CHFR impairs the machinery involved in maintaining genomic integrity. Epigenetic alteration of the genes involved in the induction of senescence is often associated with cancers showing mutations in the Ras signaling pathway. In addition to regional hypermethylation, global hypomethylation is also a common feature of tumors. Hypomethylation of short and long interspersed repetitive elements has been reported, and hypomethylation affecting the integrity of the genome has been observed in ICF syndrome and various cancers. Dissection of the epigenetic drivers of genetic instability may be important for the development of novel approaches to the treatment of cancer. PMID:20920753

Toyota, Minoru; Suzuki, Hiromu

2010-01-01

3

Multiple genetic alterations in human carcinogenesis.  

PubMed Central

Cancer development in man appeared to be a multistage process as suggested by epidemiological studies on commonly occurring gastric, colon, and breast cancers and also on human retrovirus-related leukemia, and by the finding by physicians and surgeons of precancerous lesions for many types of neoplasias. In the last 10 years it has become evident that human cancers have multiple genetic alterations caused by point mutations, recombinations, amplifications, and/or deletions. The genes affected include both oncogenes and tumor-suppressor genes and genes that accelerate cell proliferation and metastasis. Cancers with more malignant properties and poorer prognosis are generally associated with larger numbers of genetic alterations. These multiple genetic alterations are considered to be a direct reflection of the multiple steps involved in carcinogenesis. The multiple genetic alterations are caused by multiple environmental carcinogenic substances or factors, each of which usually exists only at minute concentrations and does not exert any major impact alone except under particular occupational, iatrogenic, and locally geographic conditions. The fact that carcinogenesis is a multistep process involving multiple genetic alterations clearly needs to be taken into consideration in assessing the risks of environmental carcinogenic substances or factors. The increasing incidence of multiple primary cancers is also most easily understood from the viewpoint of multiple steps in carcinogenesis. Possible multiple approaches to cancer prevention should therefore be considered in relation to multistep carcinogenesis and multiple carcinogenic factors.

Sugimura, T; Terada, M; Yokota, J; Hirohashi, S; Wakabayashi, K

1992-01-01

4

Genetic and Epigenetic Alterations in Pancreatic Carcinogenesis  

PubMed Central

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers worldwide. Despite significant progresses in the last decades, the origin of this cancer remains unclear and no efficient therapy exists. PDAC does not arise de novo: three remarkable different types of pancreatic lesions can evolve towards pancreatic cancer. These precursor lesions include: Pancreatic intraepithelial neoplasia (PanIN) that are microscopic lesions of the pancreas, Intraductal Papillary Mucinous Neoplasms (IPMN) and Mucinous Cystic Neoplasms (MCN) that are both macroscopic lesions. However, the cellular origin of these lesions is still a matter of debate. Classically, neoplasm initiation or progression is driven by several genetic and epigenetic alterations. The aim of this review is to assemble the current information on genetic mutations and epigenetic disorders that affect genes during pancreatic carcinogenesis. We will further discuss the interest of the genetic and epigenetic alterations for the diagnosis and prognosis of PDAC. Large genetic alterations (chromosomal deletion/amplification) and single point mutations are well described for carcinogenesis inducers. Mutations classically occur within key regions of the genome. Consequences are various and include activation of mitogenic pathways or silencing of apoptotic processes. Alterations of K-RAS, P16 and DPC4 genes are frequently observed in PDAC samples and have been described to arise gradually during carcinogenesis. DNA methylation is an epigenetic process involved in imprinting and X chromosome inactivation. Alteration of DNA methylation patterns leads to deregulation of gene expression, in the absence of mutation. Both genetic and epigenetic events influence genes and non-coding RNA expression, with dramatic effects on proliferation, survival and invasion. Besides improvement in our fundamental understanding of PDAC development, highlighting the molecular alterations that occur in pancreatic carcinogenesis could provide new clinical tools for early diagnosis of PDAC and the molecular basis for the development of new effective therapies.

Delpu, Yannick; Hanoun, Naima; Lulka, Hubert; Sicard, Flavie; Selves, Janick; Buscail, Louis; Torrisani, Jerome; Cordelier, Pierre

2011-01-01

5

Genetic Alterations in Colorectal Cancer  

PubMed Central

ABSTRACT Colorectal cancer (CRC) is the third most common cancer in men and the second most common cancer in women worldwide. Both genetic and epigenetic alterations are common in CRC and are the driving force of tumorigenesis. The adenoma-carcinoma sequence was proposed in the 1980s that described transformation of normal colorectal epithelium to an adenoma and ultimately to an invasive and metastatic tumor. Initial genetic changes start in an early adenoma and accumulate as it transforms to carcinoma. Chromosomal instability, microsatellite instability and CpG island methylator phenotype pathways are responsible for genetic instability in colorectal cancer. Chromosomal instability pathway consist of activation of proto-oncogenes (KRAS) and inactivation of at least three tumor suppression genes, namely loss of APC, p53 and loss of heterozogosity (LOH) of long arm of chromosome 18. Mutations of TGFBR and PIK3CA genes have also been recently described. Herein we briefly discuss the basic concepts of genetic integrity and the consequences of defects in the DNA repair relevant to CRC. Epigenetic alterations, essential in CRC tumorigenesis, are also reviewed alongside clinical information relevant to CRC.

Wilson, Jon D.; Chu, Quyen; Mills, Glenn

2012-01-01

6

Human genetic variation altering anthrax toxin sensitivity  

PubMed Central

The outcome of exposure to infectious microbes or their toxins is influenced by both microbial and host genes. Some host genes encode defense mechanisms, whereas others assist pathogen functions. Genomic analyses have associated host gene mutations with altered infectious disease susceptibility, but evidence for causality is limited. Here we demonstrate that human genetic variation affecting capillary morphogenesis gene 2 (CMG2), which encodes a host membrane protein exploited by anthrax toxin as a principal receptor, dramatically alters toxin sensitivity. Lymphoblastoid cells derived from a HapMap Project cohort of 234 persons of African, European, or Asian ancestry differed in sensitivity mediated by the protective antigen (PA) moiety of anthrax toxin by more than four orders of magnitude, with 99% of the cohort showing a 250-fold range of sensitivity. We find that relative sensitivity is an inherited trait that correlates strongly with CMG2 mRNA abundance in cells of each ethnic/geographical group and in the combined population pool (P = 4 × 10?11). The extent of CMG2 expression in transfected murine macrophages and human lymphoblastoid cells affected anthrax toxin binding, internalization, and sensitivity. A CMG2 single-nucleotide polymorphism (SNP) occurring frequently in African and European populations independently altered toxin uptake, but was not statistically associated with altered sensitivity in HapMap cell populations. Our results reveal extensive human diversity in cell lethality dependent on PA-mediated toxin binding and uptake, and identify individual differences in CMG2 expression level as a determinant of this diversity. Testing of genomically characterized human cell populations may offer a broadly useful strategy for elucidating effects of genetic variation on infectious disease susceptibility.

Martchenko, Mikhail; Candille, Sophie I.; Tang, Hua; Cohen, Stanley N.

2012-01-01

7

Genetic alterations in primary and secondary hyperparathyroidism.  

PubMed

Hyperparathyroidism refers to a term representing a wide spectrum of parathyroid disorders that are characterized by the increased production of parathyroid hormone. Hyperparathyroidism was once thought to be rare but is now more commonly recognized, affecting 1 in 500 women over 40 years of age. Yet the interpretation of parathyroid pathology is still controversial and confusing. Over the past 10 years, genetic changes (ret and menin genes) involved in the pathogenesis of MEN 2 and MEN 1 have been discovered in succession. Different mutations of the calcium-sensing receptor gene have been identified in neonatal severe hyperparathyroidism and familial hypocalciuric hypercalcemia, respectively. The HRPT 2 gene responsible for the development of hereditary hyperparathyroidism and jaw tumors has been localized on the 1q21-31 locus. Several genetic alterations have also been characterized in primary and secondary hyperparathyroidism. Different genetic alterations appear to involve the development of different types of hyperparathyroidism. These novel advances give us new insights into the pathogenesis of hyperparathyroidism and allow better differentiation between the different types of parathyroid disorders. PMID:9736402

Shan, L; Nakamura, Y; Nakamura, M; Yokoi, T; Kakudo, K

1998-08-01

8

Epigenetic Drivers of Genetic Alterations  

Microsoft Academic Search

DNA methylation plays a key role in the silencing of cancer-related genes, thereby affecting numerous cellular processes, including the cell cycle checkpoint, apoptosis, signal transduction, cell adhesion, and angiogenesis. DNA methylation also affects the expression of genes involved in maintaining the integrity of the genome through DNA repair and detoxification of reactive oxygen species. Here, we discuss how epigenetic changes

Minoru Toyota; Hiromu Suzuki

2010-01-01

9

Genetic alterations in human pancreatic cancer  

Microsoft Academic Search

Pancreatic cancers, like many other solid tumors in humans, develop and progress toward malignancy through accumulation of\\u000a multiple genetic alterations. Previous studies demonstrated that point mutations of the c-K-ras gene and inactivation of thep53 gene were frequent events in human pancreatic cancers. The high incidence of mutation at codon 12 of the c-K-ras gene, which is detectable even in early

Yoshinori Murakami

1997-01-01

10

GENETIC SCREENING: Carriers and Affected Individuals  

Microsoft Academic Search

? Abstract Genetic screening,utilizes analytical approaches,adapted,for high throughput,to identify carrier and affected individuals in a targeted population. Cur- rently, genetic screening focuses on carrier screening, prenatal screening, and newborn screening. Newborn screening should serve as a model for all genetic screening, with more than forty years of experience and numerous,lessons learned. As with all genetic screening, there are policy concerns

Linda L. McCabe; Edward R. B. McCabe

2004-01-01

11

Genetic and epigenetic alterations during renal carcinogenesis  

PubMed Central

Renal cell carcinoma (RCC) is not a single entity, but comprises a group of tumors including clear cell RCC, papillary RCC and chromophobe RCC, which arise from the epithelium of renal tubules. The majority of clear cell RCCs, the major histological subtype, have genetic or epigenetic inactivation of the von Hippel-Lindau (VHL) gene. Germline mutations in the MET and fumarate hydratase (FH) genes lead to the development of type 1 and type 2 papillary RCCs, respectively, and such mutations of either the TSC1 or TSC2 gene increase the risk of RCC. Genome-wide copy number alteration analysis has suggested that loss of chromosome 3p and gain of chromosomes 5q and 7 may be copy number aberrations indispensable for the development of clear cell RCC. When chromosome 1p, 4, 9, 13q or 14q is also lost, more clinicopathologically aggressive clear cell RCC may develop. Since renal carcinogenesis is associated with neither chronic inflammation nor persistent viral infection, and hardly any histological change is evident in corresponding non-tumorous renal tissue from patients with renal tumors, precancerous conditions in the kidney have been rarely described. However, regional DNA hypermethylation on C-type CpG islands has already accumulated in such non-cancerous renal tissues, suggesting that, from the viewpoint of altered DNA methylation, the presence of precancerous conditions can be recognized even in the kidney. Genome-wide DNA methylation profiles in precancerous conditions are basically inherited by the corresponding clear cell RCCs developing in individual patients: DNA methylation alterations at the precancerous stage may further predispose renal tissue to epigenetic and genetic alterations, generate more malignant cancers, and even determine patient outcome. The list of tumor-related genes silenced by DNA hypermethylation has recently been increasing. Genetic and epigenetic profiling provides an optimal means of prognostication for patients with RCCs. Recently developed high-throughput technologies for genetic and epigenetic analyses will further accelerate the identification of key molecules for use in the prevention, diagnosis and therapy of RCCs.

Arai, Eri; Kanai, Yae

2011-01-01

12

PRODUCTION OF EXTRACELLULAR NUCLEIC ACIDS BY GENETICALLY ALTERED BACTERIA IN AQUATIC-ENVIRONMENT MICROCOSMS  

EPA Science Inventory

Factors which affect the production of extracellular DNA by genetically altered strains of Escherichia coli, Pseudomonas aeruginosa, pseudomonas cepacia, and Bradyrhizobium japonicum in aquatic environments were investigated. he presence or absence of the ambient microbial commun...

13

Low temperature alteration processes affecting ultramafic bodies  

USGS Publications Warehouse

At low temperatures, in the presence of an aqueous solution, olivine and orthopyroxene are not stable relative to the hydrous phases brucite, serpentine and talc. Alteration of dunite and peridotite to serpentine or steatite bodies must therefore proceed via non-equilibrium processes. The compositions of natural solutions emanating from dunites and peridotites demonstrate that the dissolution of forsterite and/or enstatite is rapid compared with the precipitation of the hydrous phases; consequently, dissolution of anhydrous minerals controls the chemistry of such solutions. In the presence of an aqueous phase, precipitation of hydrous minerals is the rate-controlling step. Brucite-bearing and -deficient serpentinites alter at low temperature by non-equilibrium processes, as evidenced by the composition of natural solutions from these bodies. The solutions approach equilibrium with the least stable hydrous phase and, as a consequence, are supersaturated with other hydrous phases. Dissolution of the least stable phase is rapid compared to precipitation of other phases, so that the dissolving mineral controls the solution chemistry. Non-equilibrium alteration of anhydrous ultramafic bodies continues until at least one anhydrous phase equilibrates with brucite, chrysotile or talc. The lowest temperature (at a given pressure) at which this happens is defined by the reaction: 3H2O + 2Mg2SiO4 ??? Mg3Si2O5(OH)4 + Mg(OH)2 (Johannes, 1968, Contrib. Mineral. Petrol. 19, 309-315) so that non-equilibrium alteration may occur well into greenschist facies metamorphic conditions. ?? 1978.

Nesbitt, H. W.; Bricker, O. P.

1978-01-01

14

Update on genetic disorders affecting white matter  

Microsoft Academic Search

The classification of diseases affecting white matter has changed dramatically with the use of magnetic resonance imaging. Classical leukodystrophies, such as metachromatic leukodystrophy and Krabbe’s disease, account for only a small number of inherited diseases that affect white matter. Magnetic resonance imaging has clarified genetic disorders that result in white matter changes or leukoencephalopathies. The term leukoencephalopathy is used to

Edward M Kaye

2001-01-01

15

Molecular genetics in affective illness  

SciTech Connect

Genetic transmission in manic depressive illness (MDI) has been explored in twins, adoption, association, and linkage studies. The X-linked transmission hypothesis has been tested by using several markers on chromosome X: Xg blood group, color blindness, glucose-6-phosphate dehydrogenase (G6PD), factor IX (hemophilia B), and DNA probes such as DXS15, DXS52, F8C, ST14. The hypothesis of autosomal transmission has been tested by association studies with the O blood group located on chromosome 9, as well as linkage studies on chromosome 6 with the Human Leucocyte Antigens (HLA) haplotypes and on Chromosome 11 with DNA markers for the following genes: D2 dopamine receptor, tyrosinase, C-Harvey-Ras-A (HRAS) oncogene, insuline (ins), and tyrosine hydroxylase (TH). Although linkage studies support the hypothesis of a major locus for the transmission of MDI in the Xq27-28 region, several factors are limiting the results, and are discussed in the present review. 105 refs., 1 fig., 2 tabs.

Mendlewicz, J.; Sevy, S.; Mendelbaum, K. (Erasme Univ. Hospital, Brussels (Belgium))

1993-01-01

16

Genetics of affective and anxiety disorders.  

PubMed

The study of the genetics of complex behaviors has evolved dramatically from the days of the nature versus nurture debates that dominated much of the past century. Here we discuss advances in our understanding of the genetics of affective and anxiety disorders. In particular, we highlight our growing understanding of specific gene-environment interactions that occur during critical periods in development, setting the stage for later behavioral phenotypes. We review the recent literature in the field, focusing on recent advances in our understanding of the role of the serotonin system in establishing normal anxiety levels during development. We emphasize the importance of understanding the effect of genetic variation at the level of functional circuits and provide examples from the literature of how such an approach has been exploited to study novel genetic endpoints, including genetically based variation in response to medication, a potentially valuable phenotype that has not received much attention to date. PMID:16318591

Leonardo, E D; Hen, René

2006-01-01

17

Elevated COâ alters genetic composition in plant populations: Parallel results from two model systems  

Microsoft Academic Search

Rising atmospheric COâ concentrations, in addition to affecting global climate and carbon balance, may also have a direct impact on genetic compositions of plant populations by altering microevolutionary processes. In two model systems, an annual plant and a temperate forest tree, performance under elevated COâ was both density-dependent and strongly genotype-specific. In dense stands, pronounced shifts in genetic composition occurred

F. A. Bazzaz; M. Jasienski; S. C. Thomas

1995-01-01

18

Raman spectroscopic study of a genetically altered kidney cell  

NASA Astrophysics Data System (ADS)

A Raman spectroscopic investigation of a genetically altered Human Embryonic Kidney Cell (HEK293) along with a pathologically normal cell has been carried out by a conventional method. The genetic alteration was carried out with a standard protocol by using a Green Fluorescence Protein (GFP). Raman spectra show that there are dramatic differences between the spectrum obtained from a genetically altered cell and that obtained from a pathologically normal cell. The former shows three broad bands; meanwhile the latter shows several sharp peaks corresponding to the ring vibrational modes of Phen, GFP and DNA. The present analysis provides an indication that the force field near Phen located at 64, 65 and 66 was altered during the genetic transformation. The Raman spectrum could be a direct experimental evidence for substantial modifications triggered due to the expression of specific genes.

Joshi, Joel; Garcia, Francisco; Centeno, Silvia P.; Joshi, N. V.

2008-03-01

19

Characterization of Genetic Alterations in Ovarian Cancer.  

National Technical Information Service (NTIS)

The goal of this Program Project was to utilize genetic technologies to begin to understand the important changes that underlie ovarian cancer development. Utilizing transcriptional profiling to ascertain consistently up- and down-regulated genes, we bega...

D. I. Smith

2003-01-01

20

[Autism, genetics and synaptic function alterations].  

PubMed

Autism is a neurodevelopmental disorder characterized by a deficit of language and communication both associated with a restricted repertoire of activities and interests. The current prevalence of autistic disorder stricto sensu is estimated at 1/500 whereas autism spectrum disorders (ASD) increases up to 1/150 to 1/200. Mental deficiency (MD) and epilepsy are present in numerous autistic individuals. Consequently, autism is as a major public health issue. Autism was first considered as a non biological disease; however various rational approaches for analysing epidemiological data suggested the possibility of the influence of genetic factors. In 2003, this hypothesis was clearly illustrated by the characterization of genetic mutations transmitted through a mendelian manner. Subsequently, the glutamate synapse appeared as a preferential causal target in autism because the identified genes encoded proteins present in this structure. Strikingly, the findings that an identical genetic dysfunction of the synapse might also explain some MD suggested the possibility of a genetic comorbidity between these neurodevelopmental conditions. To date, various identified genes are considered indifferently as "autism" or "MD" genes. The characterization of mutations in the NLGN4X gene in patients with Asperger syndrome, autism without MD, or MD without autism, was the first example. It appears that a genetic continuum between ASD on one hand, and between autism and MD on the other hand, is present. Consequently, it is likely that genes already involved in MD will be found mutated in autistic patients and will represent future target for finding new factors in autism. PMID:20181440

Perche, O; Laumonnier, F; Baala, L; Ardourel, M-Y; Menuet, A; Robin, V; Mortaud, S; Montécot-Dubourg, C; Richard, O; Pichon, J; Briault, S

2010-02-23

21

Genetic Alterations in Pesticide Exposed Bolivian Farmers  

PubMed Central

Background Pesticides are of concern in Bolivia because of increasing use. Frequent intoxications have been demonstrated due to use of very toxic pesticides, insufficient control of distribution and sale and little knowledge among farmers of protective measures and hygienic procedures. Method Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated with a mean age of 37.3 years (range 17–76). Data of exposure and possible genetic damage were collected and evaluated by well known statistical methods, controlling for relevant confounders. To measure genetic damage chromosomal aberrations and the comet assay analysis were performed. Results Pesticide exposed farmers had a higher degree of genetic damage compared to the control group. The number of chromosomal aberrations increased with the intensity of pesticide exposure. Females had a lower number of chromosomal aberrations than males, and people living at altitudes above 2500 metres seemed to exhibit more DNA damage measured by the comet assay. Conclusions Bolivian farmers showed signs of genotoxic damage, probably related to exposure to pesticides. Due to the potentially negative long term health effects of genetic damage on reproduction and the development of cancer, preventive measures are recommended. Effective control with imports and sales, banning of the most toxic pesticides, education and information are possible measures, which could help preventing the negative effects of pesticides on human health and the environment.

J?rs, Erik; Gonzales, Ana Rosa; Ascarrunz, Maria Eugenia; Tirado, Noemi; Takahashi, Catharina; Lafuente, Erika; Dos Santos, Raquel A; Bailon, Natalia; Cervantes, Rafael; O, Huici; Baelum, Jesper; Lander., Flemming

2007-01-01

22

Altered Affective Response in Marijuana Smokers: An FMRI Study  

PubMed Central

More than 94 million Americans have tried marijuana, and it remains the most widely used illicit drug in the nation. Investigations of the cognitive effects of marijuana report alterations in brain function during tasks requiring executive control, including inhibition and decision-making. Endogenous cannabinoids regulate a variety of emotional responses, including anxiety, mood control, and aggression; nevertheless, little is known about smokers’ responses to affective stimuli. The anterior cingulate and amygdala play key roles in the inhibition of impulsive behavior and affective regulation, and studies using PET and fMRI have demonstrated changes within these regions in marijuana smokers. Given alterations in mood and perception often observed in smokers, we hypothesized altered fMRI patterns of response in 15 chronic heavy marijuana smokers relative to 15 non-marijuana smoking control subjects during the viewing of masked happy and fearful faces. Despite no between-group differences on clinical or demographic measures, smokers demonstrated a relative decrease in both anterior cingulate and amygdalar activity during masked affective stimuli compared to controls, who showed relative increases in activation within these regions during the viewing of masked faces. Findings indicate that chronic heavy marijuana smokers demonstrate altered activation of frontal and limbic systems while viewing masked faces, consistent with autoradiographic studies reporting high CB-1 receptor density in these regions. These data suggest differences in affective processing in chronic smokers, even when stimuli are presented below the level of conscious processing, and underscore the likelihood that marijuana smokers process emotional information differently from those who do not smoke, which may result in negative consequences.

Gruber, Staci A.; Rogowska, Jadwiga; Yurgelun-Todd, Deborah A.

2009-01-01

23

Fuel properties of oil from genetically altered Cuphea viscosissima  

Microsoft Academic Search

A genetically altered plant strain (Cuphea viscosissima VS-320) was identified which produces an oil with elevated levels of medium- and short-chain triglycerides. Previous studies have suggested that such an oil may be appropriate for use as a substitute for diesel fuel without chemical conversion of component triglycerides to methyl esters. This oil is also of interest for other industrial applications.

Daniel P. Geller; John W. Goodrum; Steven J. Knapp

1999-01-01

24

Phenotypic and Evolutionary Consequences of Social Behaviours: Interactions among Individuals Affect Direct Genetic Effects  

PubMed Central

Traditional quantitative genetics assumes that an individual's phenotype is determined by both genetic and environmental factors. For many animals, part of the environment is social and provided by parents and other interacting partners. When expression of genes in social partners affects trait expression in a focal individual, indirect genetic effects occur. In this study, we explore the effects of indirect genetic effects on the magnitude and range of phenotypic values in a focal individual in a multi-member model analyzing three possible classes of interactions between individuals. We show that social interactions may not only cause indirect genetic effects but can also modify direct genetic effects. Furthermore, we demonstrate that both direct and indirect genetic effects substantially alter the range of phenotypic values, particularly when a focal trait can influence its own expression via interactions with traits in other individuals. We derive a function predicting the relative importance of direct versus indirect genetic effects. Our model reveals that both direct and indirect genetic effects can depend to a large extent on both group size and interaction strength, altering group mean phenotype and variance. This may lead to scenarios where between group variation is much higher than within group variation despite similar underlying genetic properties, potentially affecting the level of selection. Our analysis highlights key properties of indirect genetic effects with important consequences for trait evolution, the level of selection and potentially speciation.

Trubenova, Barbora; Hager, Reinmar

2012-01-01

25

Selected genetic disorders affecting Ashkenazi Jewish families.  

PubMed

Ashkenazi Jews of Central and Eastern European ancestry have a disproportionately high prevalence of several autosomal recessive genetic disorders. This article describes these 9 disorders and their genetic inheritance patterns: Bloom syndrome; Canavan disease; cystic fibrosis; familial dysautonomia; Fanconi anemia; Gaucher disease; Mucolipidosis IV; Niemann-Pick disease; and Tay-Sachs disease. Genetic testing, counseling, and family planning options for the at-risk population are described. The role of the community health nurse is addressed. PMID:17149032

Weinstein, Lenore B

26

Telomerase Activity and Genetic Alterations in Primary Breast Carcinomas  

PubMed Central

Abstract It has been proposed that the structural and numerical chromosome abnormalities recorded in breast cancer could be the result of telomere dysfunction and that telomerase is activated de novo to provide a survival mechanism curtailing further chromosomal aberrations. However, recent in vivo and in vitro data show that the ectopic expression of telomerase promotes tumorigenesis via a telomere length-independent mechanism. In this study, the relation between telomerase expression and the extent of chromosomal aberrations was investigated in 62 primary breast carcinomas. Telomerase activity was measured using a polymerase chain reaction-based telomeric repeat amplification protocol assay and 92% of the tumors were found to express telomerase with a relative activity ranging from 0 to 3839.6. Genetic alterations were determined by G-banding and comparative genomic hybridization analysis and 97% of the tumors exhibited chromosomal aberrations ranging from 0 to 44 (average: 10.98). In the overall series, the relationship between telomerase activity levels and genetic changes could be best described by a quadratic model, whereas in tumors with below-average genetic alteration numbers, a significant positive association was recorded between the two variables (coefficient=0.374, P= .017). The relationship between telomerase activity levels and the extent of genetic alteration may reflect the complex effect of telomerase activation upon tumor progression in breast carcinomas.

Papadopoulou, Anna; Trangas, Theoni; Teixeira, Manuel R; Heim, Sverre; Dimitriadis, Euthimios; Tsarouha, Haroula; Andersen, Johan A; Evangelou, Evangelos; Ioannidis, Panayiotis; Agnantis, Niki J; Pandis, Nikos

2003-01-01

27

Allende Dark Inclusions Affected by Different Degrees of Aqueous Alteration  

NASA Astrophysics Data System (ADS)

A variety of dark inclusions (DIs) have been reported from Allende and other CV3 chondrites [e. g., 1-3]. It has been controversial whether they were formed in the solar nebula [3] or on the meteorite parent body [2]. Recent studies of some DIs [4, 5] revealed evidence suggesting that they experienced intense aqueous alteration and subsequent thermal metamorphism on the meteorite parent body. We here present the results of petrographic and scanning electron microscope studies of two DIs in Allende that are very different in mineralogy and texture from each other. One of the two DIs (16-S-1), which was previously studied by Fruland et al. [1] and Zolensky and Buchanan [6], contains abundant chondrules that are composed mainly of Mg-rich olivine and pyroxene, embedded in a fine-grained matrix. Although the general petrographic feature appears to be common to the CV3 chondrites, 16-S-1 shows several features indicative of secondary alteration. Mesostasis in most chondrules is filled with fine-grained aggregates of Si-, Al-, Ca-rich phases, which were probably formed by replacing glass. Mg-rich olivine and pyroxene, especially those adjacent to mesostasis and matrix, have Fe-rich rims. Fracture-filling veins mainly of Fe-rich olivine occur both in chondrules and matrix. As reported by Zolensky and Buchanan [6], Fe-rich olivine grains in some portions of the matrix and chondrule mesostasis show fibrous to acicular morphology, suggesting that they were produced by dehydration and thermal transformation of phyllosilicate. The textures suggest that 16-S-1 was affected by relatively minor aqueous alteration, so only the chondrule mesostasis and the edges of Mg-rich olivine and pyroxene were affected. The other DI (DN1) lacks chondrules, but instead contains rounded to oval-shaped inclusions (< 600 micrometers, mostly about 150 micrometers in diameter) that are composed mostly of fine grains (<1 to about 20 micrometers in diameter) of homogeneous Fe-rich olivine (Fo(sub)65 to about 68). Olivine grains in the inclusions commonly show fibrous morphology, suggesting pseudomorphs after phyllosilicate. Matrix is also composed mostly of Fe-rich olivine which is similar in composition to that in the inclusions. Fracture-filling veins abundantly occur around relatively large inclusions. The mineralogical and textural features suggest that DN1 was once involved in intense aqueous alteration, so that original chondrules were almost entirely replaced by phyllosilicate. Subsequently, it was dehydrated by mild heating and transformed to a nearly homogeneous aggregate of Fe-rich olivine grains. The present study reveals that both 16-S-1 and DN1 show evidence that they experienced aqueous alteration and subsequent thermal metamorphism on the meteorite parent body, although they are very different in texture and mineralogy. This suggests that such a sequence of secondary process is not unique to the DIs previously studied [4, 5] but is common to other DIs. The differences in mineralogy and texture of DIs are probably explained by different degrees of aqueous alteration in which each DI was involved before thermal metamorphism. The sequence of alteration was probably a common event that occurred near the surfaces of meteorite parent bodies. We believe that systematic studies of DIs would provide a more precise view regarding the evolution of carbonaceous chondrite parent bodies. References: [1] Fruland R. M. et al. (1978) Proc. LPSC 9th, 1305-1329. [2] Bunch T. E. and Chang S. (1983) LPS XIV, 75-76. [3] Bischoff A. et al. (1988) LPS XIX, 88-89. [4] Kojima T. et al. (1993) Meteoritics, 28, 649-658. [5] Kojima T. and Tomeoka K. (1994) Meteoritics, 29, 484. [6] Zolensky M. E. and Buchanan P. C. (1995) LPS XXVI, 1565-1566.

Kojima, T.; Tomeoka, K.

1995-09-01

28

The complex landscape of genetic alterations in mantle cell lymphoma.  

PubMed

Mantle cell lymphoma (MCL) is genetically characterized by the t(11;14)(q13;q32) which deregulates cyclin D1. Small subsets of cases have been identified with variant CCND1 translocations with the immunoglobulin light chain genes or with alternative translocations involving CCND2 and CCND3. Additionally, double-hit MCL with MYC rearrangements with a highly aggressive clinical course have been reported, but no other frequent recurrent translocations have been identified. In recent years, genome-wide screening of copy number alterations by comparative genomic hybridization and genomic microarray platforms have revealed a characteristic MCL profile of multiple secondary gains and losses as well as regions of copy number neutral loss of heterozygosity that target mainly genes involved in cell cycle regulation, DNA damage response, and cell survival pathways. Several aberrations have been found to be associated with worse prognosis, 3q gains and losses of 8p, 9p, and 17p. An increased number of secondary alterations and blastoid morphology have also been shown to be associated with cases with short survival. On the contrary, indolent MCL cases carry only the primary t(11;14) and few or no other additional genomic alterations. Altogether these observations suggest that the genetic background of MCL is an important factor that dictates their different clinical behavior. This review will focus on MCL from a genetic perspective and will present next-generation sequencing technology as a new potential tool to complement the study of complex genomes. The better understanding of genetic alterations of MCL may offer new approaches for more patient-tailored, risk-adapted treatment options. PMID:21945515

Royo, Cristina; Salaverria, Itziar; Hartmann, Elena M; Rosenwald, Andreas; Campo, Elías; Beà, Sílvia

2011-09-18

29

Age-Dependent Prognostic Effects of Genetic Alterations in Glioblastoma  

Microsoft Academic Search

Purpose: Although the genetic alterations in glioblas- toma have been well characterized, reports regarding their prognostic effects have been inconsistent. Experimental Design: In this series of 140 consecutive cases of glioblastoma treated at a single center, we analyzed the frequency, age dependency and prognostic effects of TP53 mutation, CDKN2A\\/p16 deletion, EGFR amplification, as well as loss of chromosome 1p, chromosome

Tracy T. Batchelor; Rebecca A. Betensky; J. Matthew Esposito; Loc-Duyen D. Pham; Molly V. Dorfman; Nicole Piscatelli; Sarah Jhung; David Rhee; David N. Louis

2004-01-01

30

Genetic Contributions to Altered Callosal Morphology in Schizophrenia  

Microsoft Academic Search

Patients with schizophrenia exhibit abnormalities in midsagittal corpus callosum area, shape, and\\/or displacement. Our goal was to confirm these findings and to establish the genetic and nongenetic contributions to altered callosal morphology in schizophrenia. Relationships between ventricular enlargements potentially contributing to callosal displacements were as- sessed as a secondary goal. High-resolution magnetic reso- nance images were obtained from co-twins of

Katherine L. Narr; Tyrone D. Cannon; Roger P. Woods; Paul M. Thompson; Sharon Kim; Dina Asunction; Theo G. M. van Erp; Veli-Pekka Poutanen; Matti Huttunen; Jouko Lonnqvist; Jaakko Kaprio; John C. Mazziotta; Arthur W. Toga

2002-01-01

31

Genetic alterations in poorly differentiated and undifferentiated thyroid carcinomas.  

PubMed

Thyroid gland presents a wide spectrum of tumours derived from follicular cells that range from well differentiated, papillary and follicular carcinoma (PTC and FTC, respectively), usually carrying a good prognosis, to the clinically aggressive, poorly differentiated (PDTC) and undifferentiated thyroid carcinoma (UTC).It is usually accepted that PDTC and UTC occur either de novo or progress from a pre-existing well differentiated carcinoma through a multistep process of genetic and epigenetic changes that lead to clonal expansion and neoplastic development. Mutations and epigenetic alterations in PDTC and UTC are far from being totally clarified. Assuming that PDTC and UTC may derive from well differentiated thyroid carcinomas (WDTC), it is expected that some PDTC and UTC would harbour genetic alterations that are typical of PTC and FTC. This is the case for some molecular markers (BRAF and NRAS) that are present in WDTC, PDTC and UTC. Other genes, namely P53, are almost exclusively detected in less differentiated and undifferentiated thyroid tumours, supporting a diagnosis of PDTC or, much more often, UTC. Thyroid-specific rearrangements RET/PTC and PAX8/PPAR?, on the other hand, are rarely found in PDTC and UTC, suggesting that these genetic alterations do not predispose cells to dedifferentiation. In the present review we have summarized the molecular changes associated with the two most aggressive types of thyroid cancer. PMID:22654560

Soares, Paula; Lima, Jorge; Preto, Ana; Castro, Patricia; Vinagre, João; Celestino, Ricardo; Couto, Joana P; Prazeres, Hugo; Eloy, Catarina; Máximo, Valdemar; Sobrinho-Simões, M

2011-12-01

32

Genetic Alterations in Poorly Differentiated and Undifferentiated Thyroid Carcinomas  

PubMed Central

Thyroid gland presents a wide spectrum of tumours derived from follicular cells that range from well differentiated, papillary and follicular carcinoma (PTC and FTC, respectively), usually carrying a good prognosis, to the clinically aggressive, poorly differentiated (PDTC) and undifferentiated thyroid carcinoma (UTC). It is usually accepted that PDTC and UTC occur either de novo or progress from a pre-existing well differentiated carcinoma through a multistep process of genetic and epigenetic changes that lead to clonal expansion and neoplastic development. Mutations and epigenetic alterations in PDTC and UTC are far from being totally clarified. Assuming that PDTC and UTC may derive from well differentiated thyroid carcinomas (WDTC), it is expected that some PDTC and UTC would harbour genetic alterations that are typical of PTC and FTC. This is the case for some molecular markers (BRAF and NRAS) that are present in WDTC, PDTC and UTC. Other genes, namely P53, are almost exclusively detected in less differentiated and undifferentiated thyroid tumours, supporting a diagnosis of PDTC or, much more often, UTC. Thyroid-specific rearrangements RET/PTC and PAX8/PPAR?, on the other hand, are rarely found in PDTC and UTC, suggesting that these genetic alterations do not predispose cells to dedifferentiation. In the present review we have summarized the molecular changes associated with the two most aggressive types of thyroid cancer.

Soares, Paula; Lima, Jorge; Preto, Ana; Castro, Patricia; Vinagre, Joao; Celestino, Ricardo; Couto, Joana P; Prazeres, Hugo; Eloy, Catarina; Maximo, Valdemar; Sobrinho-Simoes, M

2011-01-01

33

Alterations in the RB1 pathway in low-grade diffuse gliomas lacking common genetic alterations.  

PubMed

We recently reported that the vast majority (>90%) of low-grade diffuse gliomas (diffuse astrocytoma, oligoastrocytoma and oligodendroglioma) carry at least one of the following genetic alterations: IDH1/2 mutation, TP53 mutation or 1p/19q loss. Only 7% of cases were triple-negative (ie, lacking any of these alterations). In the present study, array comparative genomic hybridization (CGH) in 15 triple-negative WHO grade II gliomas (eight diffuse astrocytomas and seven oligodendrogliomas) showed loss at 9p21 (p14(ARF) , p15(INK4b) , p16(INK4a) loci) and 13q14-13q32 (containing the RB1 locus) in three and two cases, respectively. Further analyses in 31 triple-negative cases as well as a total of 160 non-triple-negative cases revealed that alterations in the RB1 pathway (homozygous deletion and promoter methylation of the p15(INK4b) , p16(INK4a) and RB1 genes) were significantly more frequent in triple-negative (26%) than in non-triple-negative cases (11%; P?=?0.0371). Multivariate analysis after adjustment for age, histology and treatment showed that RB1 pathway alterations were significantly associated with unfavorable outcome for patients with low-grade diffuse glioma [hazard ratio, 3.024 (1.279-6.631); P?=?0.0057]. These results suggest that a fraction of low-grade diffuse gliomas lacking common genetic alterations may develop through a distinct genetic pathway, which may include loss of cell-cycle control regulated by the RB1 pathway. PMID:21470325

Kim, Young-Ho; Lachuer, Joel; Mittelbronn, Michel; Paulus, Werner; Brokinkel, Benjamin; Keyvani, Kathy; Sure, Ulrich; Wrede, Karsten; Nobusawa, Sumihito; Nakazato, Yoichi; Tanaka, Yuko; Vital, Anne; Mariani, Luigi; Ohgaki, Hiroko

2011-05-30

34

Human genetic variation influences vitamin C homeostasis by altering vitamin C transport and antioxidant enzyme function.  

PubMed

New evidence for the regulation of vitamin C homeostasis has emerged from several studies of human genetic variation. Polymorphisms in the genes encoding sodium-dependent vitamin C transport proteins are strongly associated with plasma ascorbate levels and likely impact tissue cellular vitamin C status. Furthermore, genetic variants of proteins that suppress oxidative stress or detoxify oxidatively damaged biomolecules, i.e., haptoglobin, glutathione-S-transferases, and possibly manganese superoxide dismutase, affect ascorbate levels in the human body. There also is limited evidence for a role of glucose transport proteins. In this review, we examine the extent of the variation in these genes, their impact on vitamin C status, and their potential role in altering chronic disease risk. We conclude that future epidemiological studies should take into account genetic variation in order to successfully determine the role of vitamin C nutriture or supplementation in human vitamin C status and chronic disease risk. PMID:23642198

Michels, Alexander J; Hagen, Tory M; Frei, Balz

2013-04-29

35

Minireview: Molecular genetics in affective illness.  

PubMed

Genetic transmission in manic depressive illness (MDI) has been explored in twins, adoption, association, and linkage studies. The X-linked transmission hypothesis has been tested by using several markers on chromosome X: Xg blood group, colour blindness, glucose-6-phosphate dehydrogenase (G6PD), factor IX (haemophilia B), and DNA probes such as DXS15, DXS52, F8C, ST14. The hypothesis of autosomal transmission has been tested by association studies with the O blood group located on chromosome 9, as well as linkage studies on chromosome 6 with the Human Leucocyte Antigens (HLA) haplotypes and on Chromosome 11 with DNA markers for the following genes: D2 dopamine receptor, tyrosinase, C-Harvey-Ras-A (HRAS) oncogene, insuline (ins), and tyrosine hydroxylase (TH). Although linkage studies support the hypothesis of a major locus for the transmission of MDI in the Xq27-28 region, several factors are limiting the results, and are discussed in the present review. PMID:8423707

Mendlewicz, J; Sevy, S; Mendelbaum, K

1993-01-01

36

Altered affective response in marijuana smokers: An FMRI study  

Microsoft Academic Search

More than 94 million Americans have tried marijuana, and it remains the most widely used illicit drug in the nation. Investigations of the cognitive effects of marijuana report alterations in brain function during tasks requiring executive control, including inhibition and decision-making. Endogenous cannabinoids regulate a variety of emotional responses, including anxiety, mood control, and aggression; nevertheless, little is known about

Staci A. Gruber; Jadwiga Rogowska; Deborah A. Yurgelun-Todd

2009-01-01

37

Altered Sleep and Affect in the Neurotensin Receptor 1 Knockout Mouse  

PubMed Central

Study Objective: Sleep and mood disorders have long been understood to have strong genetic components, and there is considerable comorbidity of sleep abnormalities and mood disorders, suggesting the involvement of common genetic pathways. Here, we examine a candidate gene implicated in the regulation of both sleep and affective behavior using a knockout mouse model. Design: Previously, we identified a quantitative trait locus (QTL) for REM sleep amount, REM sleep bout number, and wake amount in a genetically segregating population of mice. Here, we show that traits mapping to this QTL correlated with an expression QTL for neurotensin receptor 1 (Ntsr1), a receptor for neurotensin, a ligand known to be involved in several psychiatric disorders. We examined sleep as well as behaviors indicative of anxiety and depression in the NTSR1 knockout mouse. Measurements and Results: NTSR1 knockouts had a lower percentage of sleep time spent in REM sleep in the dark phase and a larger diurnal variation in REM sleep duration than wild types under baseline conditions. Following sleep deprivation, NTSR1 knockouts exhibited more wake and less NREM rebound sleep. NTSR1 knockouts also showed increased anxious and despair behaviors. Conclusions: Here we illustrate a link between expression of the Ntsr1 gene and sleep traits previously associated with a particular QTL. We also demonstrate a relationship between Ntsr1 and anxiety and despair behaviors. Given the considerable evidence that anxiety and depression are closely linked with abnormalities in sleep, the data presented here provide further evidence that neurotensin and Ntsr1 may be a component of a pathway involved in both sleep and mood disorders. Citation: Fitzpatrick K; Winrow CJ; Gotter AL; Millstein J; Arbuzova J; Brunner J; Kasarskis A; Vitaterna MH; Renger JJ; Turek FW. Altered sleep and affect in the neurotensin receptor 1 knockout mouse. SLEEP 2012;35(7):949-956.

Fitzpatrick, Karrie; Winrow, Christopher J.; Gotter, Anthony L.; Millstein, Joshua; Arbuzova, Janna; Brunner, Joseph; Kasarskis, Andrew; Vitaterna, Martha H.; Renger, John J.; Turek, Fred W.

2012-01-01

38

Evidence for altered hepatic matrix degradation in genetic haemochromatosis  

PubMed Central

Background—Altered matrix degradation contributes to fibrosis in some liver diseases but the role of matrix degradation in fibrogenesis associated with genetic haemochromatosis has not previously been addressed. ?Aims—To measure serum concentrations of tissue inhibitor of metalloproteinase 1 (TIMP-1) and matrix metalloproteinases (MMP), MMP-1, MMP-2, and MMP-3 in patients with haemochromatosis and control subjects. ?Patients—Forty patients with haemochromatosis and 19 healthy control subjects. Ten of the 40 patients were studied before and after venesection therapy. ?Methods—Serum levels of TIMP-1, MMP-1, MMP-2, and MMP-3 were measured by enzyme immunoassay and correlated to hepatic iron concentration and degree of histological fibrosis. ?Results—Serum TIMP-1 was increased in patients with haemochromatosis compared with controls (163 (30) versus 123 (28) ng/ml, p<0.0002). Mean serum TIMP-1 concentration of patients with haemochromatosis without fibrosis was significantly higher than in controls (153(16) versus 123 (28) ng/ml, p=0.03). Serum TIMP-1 concentration correlated with both hepatic iron concentration and hepatic iron index (r=0.42, p<0.01; r=0.42, p<0.01). Serum MMP-2 concentrations correlated with increasing degree of fibrosis in patients with haemochromatosis (r=0.38, p=0.01). The mean MMP-1:TIMP-1, MMP-2:TIMP-1 and age/sex matched MMP-3:TIMP-1 ratios were significantly lower in patients with haemochromatosis than controls (0.11 (0.06) versus 0.2 (0.14), p=0.02; 3.32 (0.9) versus 3.91 (0.81), p=0.05; and 0.26 (0.12) versus 0.47 (0.27), p=0.007, respectively). Following venesection, MMP-2 and MMP-3 concentrations increased by 11% (p=0.03) and 19% (p=0.03), respectively. ?Conclusions—This study provides the first evidence of an alteration in matrix degradation in haemochromatosis that may be a contributing factor to hepatic fibrogenesis in this disease. ?? Keywords: hepatic stellate cell; hepatic fibrosis; matrix metalloproteinase; tissue inhibitor of metalloproteinase-1; genetic haemochromatosis

George, D; Ramm, G; Powell, L; Fletcher, L; Walker, N; Cowley, L; Crawford, D

1998-01-01

39

Altered functional differentiation of mesoangioblasts in a genetic myopathy.  

PubMed

Mutations underlying genetic cardiomyopathies might affect differentiation commitment of resident progenitor cells. Cardiac mesoangioblasts (cMabs) are multipotent progenitor cells resident in the myocardium. A switch from cardiac to skeletal muscle differentiation has been recently described in cMabs from ?-sarcoglycan-null mice (?SG(-/-)), a murine model of genetic myopathy with early myocardial involvement. Although complementation with ?SG gene was inconsequential, knock-in of miRNA669a (missing in ?SG(-/-) cMabs) partially rescued the mutation-induced molecular phenotype. Here, we undertook a detailed evaluation of functional differentiation of ?SG(-/-) cMabs and tested the effects of miRNA669a-induced rescue in vitro. To this end, cMabs were compared with neonatal cardiomyocytes (CMs) and skeletal muscle C2C12 cells, representative of cardiac and skeletal muscle respectively. Consistent with previous data on molecular patterns, electrophysiological and Ca(2+)-handling properties of ?SG(-/-) cMabs were closer to C2C12 cells than to CM ones. Nevertheless, subtler aspects, including action potential contour, Ca(2+)-spark properties and RyR isoform expression, distinguished ?SG(-/-) cMabs from C2C12 cells. Contrary to previous reports, wild-type cMabs failed to show functional differentiation towards either cell type. Knock-in of miRNA669a in ?SG(-/-) cMabs rescued the wild-type functional phenotype, i.e. it completely prevented development of skeletal muscle functional responses. We conclude that miRNA669a expression, ablated by ?SG deletion, may prevent functional differentiation of cMabs towards the skeletal muscle phenotype. PMID:23387296

Altomare, Claudia; Barile, Lucio; Rocchetti, Marcella; Sala, Luca; Crippa, Stefania; Sampaolesi, Maurilio; Zaza, Antonio

2013-02-07

40

Altering ligament water content affects ligament pre-stress and creep behaviour  

Microsoft Academic Search

The water content of a ligament can be altered by injury and surgical intervention in vivo, and inadvertently or purposely during in vitro tests. We investigated how altering the water content of the rabbit medial collateral ligament (MCL) affected its resulting creep behaviour (defined as an increase in strain from sequential cyclic and static creep tests). The water content of

G. M. Thornton; N. G. Shrive; C. B. Frank

2001-01-01

41

Alteration of proteoglycan sulfation affects bone growth and remodeling.  

PubMed

Diastrophic dysplasia (DTD) is a chondrodysplasia caused by mutations in the SLC26A2 gene, leading to reduced intracellular sulfate pool in chondrocytes, osteoblasts and fibroblasts. Hence, proteoglycans are undersulfated in the cartilage and bone of DTD patients. To characterize the bone phenotype of this skeletal dysplasia we used the Slc26a2 knock-in mouse (dtd mouse), that was previously validated as an animal model of DTD in humans. X-rays, bone densitometry, static and dynamic histomorphometry, and in vitro studies revealed a primary bone defect in the dtd mouse model. We showed in vivo that this primary bone defect in dtd mice is due to decreased bone accrual associated with a decreased trabecular and periosteal appositional rate at the cell level in one month-old mice. Although the osteoclast number evaluated by histomorphometry was not different in dtd compared to wild-type mice, urine analysis of deoxypyridinoline cross-links and serum levels of type I collagen C-terminal telopeptides showed a higher resorption rate in dtd mice compared to wild-type littermates. Electron microscopy studies showed that collagen fibrils in bone were thinner and less organized in dtd compared to wild-type mice. These data suggest that the low bone mass observed in mutant mice could possibly be linked to the different bone matrix compositions/organizations in dtd mice triggering changes in osteoblast and osteoclast activities. Overall, these results suggest that proteoglycan undersulfation not only affects the properties of hyaline cartilage, but can also lead to unbalanced bone modeling and remodeling activities, demonstrating the importance of proteoglycan sulfation in bone homeostasis. PMID:23369989

Gualeni, Benedetta; de Vernejoul, Marie-Christine; Marty-Morieux, Caroline; De Leonardis, Fabio; Franchi, Marco; Monti, Luca; Forlino, Antonella; Houillier, Pascal; Rossi, Antonio; Geoffroy, Valerie

2013-01-28

42

Production of extracellular nucleic acids by genetically altered bacteria in aquatic-environment microcosms.  

PubMed Central

The factors which affect the production of extracellular DNA by genetically altered strains of Escherichia coli, Pseudomonas aeruginosa, Pseudomonas cepacia, and Bradyrhizobium japonicum in aquatic environments were investigated. Cellular nucleic acids were labeled in vivo by incubation with [3H]thymidine or [3H]adenine, and production of extracellular DNA in marine waters, artificial seawater, or minimal salts media was determined by detecting radiolabeled macromolecules in incubation filtrates. The presence or absence of the ambient microbial community had little effect on the production of extracellular DNA. Three of four organisms produced the greatest amounts of extracellular nucleic acids when incubated in low-salinity media (2% artificial seawater) rather than high-salinity media (10 to 50% artificial seawater). The greatest production of extracellular nucleic acids by P. cepacia occurred at pH 7 and 37 degrees C, suggesting that extracellular-DNA production may be a normal physiologic function of the cell. Incubation of labeled P. cepacia cells in water from Bimini Harbor, Bahamas, resulted in labeling of macromolecules of the ambient microbial population. Collectively these results indicate that (i) extracellular-DNA production by genetically altered bacteria released into aquatic environments is more strongly influenced by physiochemical factors than biotic factors, (ii) extracellular-DNA production rates are usually greater for organisms released in freshwater than marine environments, and (iii) ambient microbial populations can readily utilize materials released by these organisms.

Paul, J H; David, A W

1989-01-01

43

Genetically altered mice: phenotypes, no phenotypes, and Faux phenotypes  

Microsoft Academic Search

‘Phenotype’ means different things, but whatever the measure, phenotype can be profoundly influenced by genetic, environmental and infectious variables. The laboratory mouse is a complex multisystemic organism which, despite its genetically inbred nature, as highly variable pathophysiologic characteristics. Mouse strains have background characteristics that can influence genomics research. In addition to the mouse itself, different approaches toward creating mutant mice

Stephen W. Barthold

2004-01-01

44

Genetic, epigenetic and stem cell alterations in endometriosis: new insights and potential therapeutic perspectives.  

PubMed

Human endometrium is a highly dynamic tissue, undergoing periodic growth and regression at each menstrual cycle. Endometriosis is a frequent chronic pathological status characterized by endometrial tissue with an ectopic localization, causing pelvic pain and infertility and a variable clinical presentation. In addition, there is well-established evidence that, although endometriosis is considered benign, it is associated with an increased risk of malignant transformation in approximately 1.0% of affected women, with the involvement of multiple pathways of development. Increasing evidence supports a key contribution of different stem/progenitor cell populations not only in the cyclic regeneration of eutopic endometrium, but also in the pathogenesis of at least some types of endometriosis. Evidence has arisen from experiments in animal models of disease through different kinds of assays (including clonogenicity, the label-retaining cell approach, the analysis of undifferentiation markers), as well as from descriptive studies on ectopic and eutopic tissue samples harvested from affected women. Changes in stem cell populations in endometriotic lesions are associated with genetic and epigenetic alterations, including imbalance of miRNA expression, histone and DNA modifications and chromosomal aberrations. The present short review mainly summarizes the latest observations contributing to the current knowledge regarding the presence and the potential contribution of stem/progenitor cells in eutopic endometrium and the aetiology of endometriosis, together with a report of the most recently identified genetic and epigenetic alterations in endometriosis. We also describe the potential advantages of single cell molecular profiling in endometrium and in endometriotic lesions. All these data can have clinical implications and provide a basis for new potential therapeutic applications. PMID:24059589

Forte, Amalia; Cipollaro, Marilena; Galderisi, Umberto

2014-01-01

45

Integrated profiling reveals a global correlation between epigenetic and genetic alterations in mesothelioma  

PubMed Central

Development of mesothelioma is linked mainly to asbestos exposure but the combined contributions of genetic and epigenetic alterations are unclear. We investigated the potential relationships between gene copy number (CN) alterations and DNA methylation profiles in a case series of pleural mesotheliomas (n=23). There were no instances of significantly correlated CN alteration and methylation at probed loci, whereas averaging loci over their associated genes revealed only two genes with significantly correlated CN and methylation alterations. In contrast to the lack of discrete correlations, the overall extent of tumor CN alteration was significantly associated with DNA methylation profile when comparing CN alteration extent among methylation profile classes. Further, there was evidence that this association was partially attributable to prevalent allele loss at the DNA methyltransferase gene DNMT1. Our findings define a strong association between global genetic and global epigenetic dysregulation in mesothelioma, rather than a discrete, local coordination of gene inactivation.

Christensen, Brock C.; Houseman, E. Andres; Poage, Graham M.; Godleski, John J.; Bueno, Raphael; Sugarbaker, David J.; Wiencke, John K.; Nelson, Heather H.; Marsit, Carmen J.; Kelsey, Karl T.

2010-01-01

46

Genetically altered mice: phenotypes, no phenotypes, and Faux phenotypes  

Microsoft Academic Search

‘Phenotype’ means different things, but whatever the measure, phenotype can be profoundly influenced by genetic, environmental\\u000a and infectious variables. The laboratory mouse is a complex multisystemic organism which, despite its genetically inbred nature,\\u000a as highly variable pathophysiologic characteristics. Mouse strains have background characteristics that can influence genomics\\u000a research. In addition to the mouse itself, different approaches toward creating mutant mice

Stephen W. Barthold

47

DNA fingerprinting techniques for the analysis of genetic and epigenetic alterations in colorectal cancer  

Microsoft Academic Search

Genetic somatic alterations are fundamental hallmarks of cancer. In addition to point and other small mutations targeting cancer genes, solid tumors often exhibit aneuploidy as well as multiple chromosomal rearrangements of large fragments of the genome. Whether somatic chromosomal alterations and aneuploidy are a driving force or a mere consequence of tumorigenesis remains controversial. Recently it became apparent that not

Johanna K. Samuelsson; Sergio Alonso; Fumiichiro Yamamoto; Manuel Perucho

2010-01-01

48

Evidence that disease-induced population decline changes genetic structure and alters dispersal patterns in the Tasmanian devil.  

PubMed

Infectious disease has been shown to be a major cause of population declines in wild animals. However, there remains little empirical evidence on the genetic consequences of disease-mediated population declines, or how such perturbations might affect demographic processes such as dispersal. Devil facial tumour disease (DFTD) has resulted in the rapid decline of the Tasmanian devil, Sarcophilus harrisii, and threatens to cause extinction. Using 10 microsatellite DNA markers, we compared genetic diversity and structure before and after DFTD outbreaks in three Tasmanian devil populations to assess the genetic consequences of disease-induced population decline. We also used both genetic and demographic data to investigate dispersal patterns in Tasmanian devils along the east coast of Tasmania. We observed a significant increase in inbreeding (F(IS) pre/post-disease -0.030/0.012, P<0.05; relatedness pre/post-disease 0.011/0.038, P=0.06) in devil populations after just 2-3 generations of disease arrival, but no detectable change in genetic diversity. Furthermore, although there was no subdivision apparent among pre-disease populations (?=0.005, 95% confidence interval (CI) -0.003 to 0.017), we found significant genetic differentiation among populations post-disease (?=0.020, 0.010-0.027), apparently driven by a combination of selection and altered dispersal patterns of females in disease-affected populations. We also show that dispersal is male-biased in devils and that dispersal distances follow a typical leptokurtic distribution. Our results show that disease can result in genetic and demographic changes in host populations over few generations and short time scales. Ongoing management of Tasmanian devils must now attempt to maintain genetic variability in this species through actions designed to reverse the detrimental effects of inbreeding and subdivision in disease-affected populations. PMID:20216571

Lachish, S; Miller, K J; Storfer, A; Goldizen, A W; Jones, M E

2010-03-10

49

Evidence that disease-induced population decline changes genetic structure and alters dispersal patterns in the Tasmanian devil  

PubMed Central

Infectious disease has been shown to be a major cause of population declines in wild animals. However, there remains little empirical evidence on the genetic consequences of disease-mediated population declines, or how such perturbations might affect demographic processes such as dispersal. Devil facial tumour disease (DFTD) has resulted in the rapid decline of the Tasmanian devil, Sarcophilus harrisii, and threatens to cause extinction. Using 10 microsatellite DNA markers, we compared genetic diversity and structure before and after DFTD outbreaks in three Tasmanian devil populations to assess the genetic consequences of disease-induced population decline. We also used both genetic and demographic data to investigate dispersal patterns in Tasmanian devils along the east coast of Tasmania. We observed a significant increase in inbreeding (FIS pre/post-disease ?0.030/0.012, P<0.05; relatedness pre/post-disease 0.011/0.038, P=0.06) in devil populations after just 2–3 generations of disease arrival, but no detectable change in genetic diversity. Furthermore, although there was no subdivision apparent among pre-disease populations (?=0.005, 95% confidence interval (CI) ?0.003 to 0.017), we found significant genetic differentiation among populations post-disease (?=0.020, 0.010–0.027), apparently driven by a combination of selection and altered dispersal patterns of females in disease-affected populations. We also show that dispersal is male-biased in devils and that dispersal distances follow a typical leptokurtic distribution. Our results show that disease can result in genetic and demographic changes in host populations over few generations and short time scales. Ongoing management of Tasmanian devils must now attempt to maintain genetic variability in this species through actions designed to reverse the detrimental effects of inbreeding and subdivision in disease-affected populations.

Lachish, S; Miller, K J; Storfer, A; Goldizen, A W; Jones, M E

2011-01-01

50

A natural genetic polymorphism affects retroactive interference in Drosophila melanogaster.  

PubMed

As environments change, animals update their internal representations of the external world. New information about the environment is learned and retained whereas outdated information is disregarded or forgotten. Retroactive interference (RI) occurs when the retrieval of previously learned information is less available owing to the acquisition of recently acquired information. Even though RI is thought to be a major cause of forgetting, its functional significance is still under debate. We find that natural allelic variants of the Drosophila melanogaster foraging gene known to affect rover and sitter behaviour differ in RI. More specifically, rovers who were previously shown to experience greater environmental heterogeneity while foraging display RI whereas sitters do not. Rover responses are biased towards more recent learning events. These results provide an ecological context to investigate the function of forgetting via RI and a suitable genetic model organism to address the evolutionary relevance of cognitive tasks. PMID:20667877

Reaume, Christopher J; Sokolowski, Marla B; Mery, Frederic

2010-07-28

51

Efficient quantitative morphological phenotyping of genetically altered organisms using stereology  

Microsoft Academic Search

Genetically modified organisms present the challenge of quantifying structures and functions in organs, tissues and cells.\\u000a Morphological investigation is greatly facilitated by taking sections in MRI, CAT scanning, histological preparations or EM,\\u000a and powerful unbiased quantitative tools called stereology can use these sections in a sampling based approach to measure\\u000a volume, number surface and length. Stereological tools have become methods

John Milton Lucocq

2007-01-01

52

Clinical implications of DNA repair genetic alterations in cancer  

Microsoft Academic Search

Summary  The overall prognosis of advanced cancer remains poor. Whilst accumulation of genetic mutations drives the cancerous phenotype,\\u000a it is well known that DNA damaging lesions that lead to such mutations are predominantly monitored and repaired by the highly\\u000a conserved DNA repair machinery in cells. Though chemotherapy as well as radiotherapy remains the mainstay of treatment, it\\u000a is clear that the

L. Gossage; M. Mohammed; S. Madhusudan

2009-01-01

53

Genetic alteration of Zymomonas mobilis for ethanol production  

SciTech Connect

Strain improvement by mutagenesis with UV resulted in Zymomonas mobilis strains which were highly EtOH and temperature tolerant and which were able to produce more than 100 g EtOH /h at EtOH concentrations of 80-90 g/L. Genetic engineering has the potential of producing strains with the ability to ferment starch and cellulose directly to EtOH.

Skotnicki, M.L.; Lee, K.J.; Tribe, D.E.; Rogers, P.L.

1982-01-01

54

GM1 gangliosidosis and Morquio B disease: an update on genetic alterations and clinical findings.  

PubMed

GM1 gangliosidosis and Morquio B syndrome, both arising from beta-galactosidase (GLB1) deficiency, are very rare lysosomal storage diseases with an incidence of about 1:100,000-1:200,000 live births worldwide. Here we report the beta-galactosidase gene (GLB1) mutation analysis of 21 unrelated GM1 gangliosidosis patients, and of 4 Morquio B patients, of whom two are brothers. Clinical features of the patients were collected and compared with those in literature. In silico analyses were performed by standard alignments tools and by an improved version of GLB1 three-dimensional models. The analysed cohort includes remarkable cases. One patient with GM1 gangliosidosis had a triple X syndrome. One patient with juvenile GM1 gangliosidosis was homozygous for a mutation previously identified in Morquio type B. A patient with infantile GM1 gangliosidosis carried a complex GLB1 allele harbouring two genetic variants leading to p.R68W and p.R109W amino acid changes, in trans with the known p.R148C mutation. Molecular analysis showed 27 mutations, 9 of which are new: 5 missense, 3 microdeletions and a nonsense mutation. We also identified four new genetic variants with a predicted polymorphic nature that was further investigated by in silico analyses. Three-dimensional structural analysis of GLB1 homology models including the new missense mutations and the p.R68W and p.R109W amino acid changes showed that all the amino acid replacements affected the resulting protein structures in different ways, from changes in polarity to folding alterations. Genetic and clinical associations led us to undertake a critical review of the classifications of late-onset GM1 gangliosidosis and Morquio B disease. PMID:21497194

Caciotti, Anna; Garman, Scott C; Rivera-Colón, Yadilette; Procopio, Elena; Catarzi, Serena; Ferri, Lorenzo; Guido, Carmen; Martelli, Paola; Parini, Rossella; Antuzzi, Daniela; Battini, Roberta; Sibilio, Michela; Simonati, Alessandro; Fontana, Elena; Salviati, Alessandro; Akinci, Gulcin; Cereda, Cristina; Dionisi-Vici, Carlo; Deodato, Francesca; d'Amico, Adele; d'Azzo, Alessandra; Bertini, Enrico; Filocamo, Mirella; Scarpa, Maurizio; di Rocco, Maja; Tifft, Cynthia J; Ciani, Federica; Gasperini, Serena; Pasquini, Elisabetta; Guerrini, Renzo; Donati, Maria Alice; Morrone, Amelia

2011-04-07

55

GM1 gangliosidosis and Morquio B disease: an update on genetic alterations and clinical findings  

PubMed Central

GM1 gangliosidosis and Morquio B syndrome, both arising from beta-galactosidase (GLB1) deficiency, are very rare lysosomal storage diseases with an incidence of about 1:100,000– 1:200,000 live births worldwide. Here we report the beta-galactosidase gene (GLB1) mutation analysis of 21 unrelated GM1 gangliosidosis patients, and of 4 Morquio B patients, of whom two are brothers. Clinical features of the patients were collected and compared with those in literature. In silico analyses were performed by standard alignments tools and by an improved version of GLB1 three-dimensional models. The analysed cohort includes remarkable cases. One patient with GM1 gangliosidosis had a triple X syndrome. One patient with juvenile GM1 gangliosidosis was homozygous for a mutation previously identified in Morquio type B. A patient with infantile GM1 gangliosidosis carried a complex GLB1 allele harbouring two genetic variants leading to p.R68W and p.R109W amino acid changes, in trans with the known p.R148C mutation. Molecular analysis showed 27 mutations, 9 of which are new: 5 missense, 3 microdeletions and a nonsense mutation. We also identified four new genetic variants with a predicted polymorphic nature that was further investigated by in silico analyses. Three-dimensional structural analysis of GLB1 homology models including the new missense mutations and the p.R68W and p.R109W amino acid changes, showed that all the amino acids replacements affected the resulting protein structures in different ways, from changes in polarity to folding alterations. Genetic and clinical associations led us to undertake a critical review of the classifications of late-onset GM1 gangliosidosis and Morquio B disease.

Caciotti, Anna; Garman, Scott C; Rivera-Colon, Yadilette; Procopio, Elena; Catarzi, Serena; Ferri, Lorenzo; Guido, Carmen; Martelli, Paola; Parini, Rossella; Antuzzi, Daniela; Battini, Roberta; Sibilio, Michela; Simonati, Alessandro; Fontana, Elena; Salviati, Alessandro; Akinci, Gulcin; Cereda, Cristina; Dionisi-Vici, Carlo; Deodato, Francesca; d'Amico, Adele; d'Azzo, Alessandra; Bertini, Enrico; Filocamo, Mirella; Scarpa, Maurizio; di Rocco, Maja; Tifft, Cynthia J; Ciani, Federica; Gasperini, Serena; Pasquini, Elisabetta; Guerrini, Renzo; Donati, Maria Alice; Morrone, Amelia

2011-01-01

56

Genetic alteration of endothelial heparan sulfate selectively inhibits tumor angiogenesis  

PubMed Central

To examine the role of endothelial heparan sulfate during angiogenesis, we generated mice bearing an endothelial-targeted deletion in the biosynthetic enzyme N-acetylglucosamine N-deacetylase/N-sulfotransferase 1 (Ndst1). Physiological angiogenesis during cutaneous wound repair was unaffected, as was growth and reproductive capacity of the mice. In contrast, pathological angiogenesis in experimental tumors was altered, resulting in smaller tumors and reduced microvascular density and branching. To simulate the angiogenic environment of the tumor, endothelial cells were isolated and propagated in vitro with proangiogenic growth factors. Binding of FGF-2 and VEGF164 to cells and to purified heparan sulfate was dramatically reduced. Mutant endothelial cells also exhibited altered sprouting responses to FGF-2 and VEGF164, reduced Erk phosphorylation, and an increase in apoptosis in branching assays. Corresponding changes in growth factor binding to tumor endothelium and apoptosis were also observed in vivo. These findings demonstrate a cell-autonomous effect of heparan sulfate on endothelial cell growth in the context of tumor angiogenesis.

Fuster, Mark M.; Wang, Lianchun; Castagnola, Janice; Sikora, Lyudmila; Reddi, Krisanavane; Lee, Phillip H.A.; Radek, Katherine A.; Schuksz, Manuela; Bishop, Joseph R.; Gallo, Richard L.; Sriramarao, P.; Esko, Jeffrey D.

2007-01-01

57

Biochemical genetics of altered acetylcholinesterase resistance to insecticides in the house fly  

Microsoft Academic Search

Resistance to the organophosphate insecticide tetrachlorvinphos was examined in a house fly (Musca domestica L.) strain with an altered acetylcholinesterase (AChE) of decreased sensitivity to inhibition by the insecticide. Genetic tests showed that both resistance and the altered AChE were controlled by semidominant gene(s) on chromosome II. The gene for resistance was five crossover units from the mutant marker stubby

F. W. Plapp; R. K. Tripathi

1978-01-01

58

Dietary and genetic manipulations of folate metabolism differentially affect neocortical functions in mice.  

PubMed

Converging evidence suggests that folate-mediated one-carbon metabolism may modulate cognitive functioning throughout the lifespan, but few studies have directly tested this hypothesis. This study examined the separate and combined effects of dietary and genetic manipulations of folate metabolism on neocortical functions in mice, modeling a common genetic variant in the MTHFD1 gene in humans. Mutant (Mthfd1(gt/+)) and wildtype (WT) male mice were assigned to a folate sufficient or deficient diet at weaning and continued on these diets throughout testing on a series of visual attention tasks adapted from the 5-choice serial reaction time task. WT mice on a deficient diet exhibited impulsive responding immediately following a change in task parameters that increased demands on attention and impulse control, and on trials following an error. This pattern of findings indicates a heightened affective response to stress and/or an inability to regulate negative emotions. In contrast, Mthfd1(gt/+) mice (regardless of diet) exhibited attentional dysfunction and a blunted affective response to committing an error. The Mthfd1(gt/+) mice also showed significantly decreased expression levels for genes encoding choline dehydrogenase and the alpha 7 nicotinic cholinergic receptor. The effects of the MTHFD1 mutation were less pronounced when combined with a deficient diet, suggesting a compensatory mechanism to the combined genetic and dietary perturbation of folate metabolism. These data demonstrate that common alterations in folate metabolism can produce functionally distinct cognitive and affective changes, and highlight the importance of considering genotype when making dietary folate recommendations. PMID:23684804

Ash, J A; Jiang, X; Malysheva, O V; Fiorenza, C G; Bisogni, A J; Levitsky, D A; Strawderman, M S; Caudill, M A; Stover, P J; Strupp, B J

2013-05-15

59

Altered Striatal Activation Predicting Real-World Positive Affect in Adolescent Major Depressive Disorder  

PubMed Central

Objective Alterations in reward-related brain function and phenomenological aspects of positive affect are increasingly examined in the development of major depressive disorder. The authors tested differences in reward-related brain function in healthy and depressed adolescents, and the authors examined direct links between reward-related brain function and positive mood that occurred in real-world contexts. Method Fifteen adolescents with major depressive disorder and 28 adolescents with no history of psychiatric disorder, ages 8–17 years, completed a functional magnetic resonance imaging guessing task involving monetary reward. Participants also reported their subjective positive affect in natural environments during a 4-day cell-phone-based ecological momentary assessment. Results Adolescents with major depressive disorder exhibited less striatal response than healthy comparison adolescents during reward anticipation and reward outcome, but more response in dorsolateral and medial prefrontal cortex. Diminished activation in a caudate region associated with this depression group difference was correlated with lower subjective positive affect in natural environments, particularly within the depressed group. Conclusions Results support models of altered reward processing and related positive affect in young people with major depressive disorder and indicate that depressed adolescents’ brain response to monetary reward is related to their affective experience in natural environments. Additionally, these results suggest that reward-processing paradigms capture brain function relevant to real-world positive affect.

Forbes, Erika E.; Hariri, Ahmad R.; Martin, Samantha L.; Silk, Jennifer S.; Moyles, Donna L.; Fisher, Patrick M.; Brown, Sarah M.; Ryan, Neal D.; Birmaher, Boris; Axelson, David A.; Dahl, Ronald E.

2009-01-01

60

Genetic Determinants of Altered Virulence of Taiwanese Foot-and-Mouth Disease Virus  

Microsoft Academic Search

In 1997, a devastating outbreak of foot-and-mouth disease (FMD) in Taiwan was caused by a serotype O virus (referred to here as OTai) with atypical virulence. It produced high morbidity and mortality in swine but did not affect cattle. We have defined the genetic basis of the species specificity of OTai by evaluating the properties of genetically engineered chimeric viruses

CLAYTON W. BEARD; PETER W. MASON

2000-01-01

61

The potential for genetically altered microglia to influence glioma treatment.  

PubMed

Diffuse and unstoppable infiltration of brain and spinal cord tissue by neoplastic glial cells is the single most important therapeutic problem posed by the common glioma group of tumors: astrocytoma, oligoastrocytoma, oligodendroglioma, their malignant variants and glioblastoma. These neoplasms account for more than two thirds of all malignant central nervous system tumors. However, most glioma research focuses on an examination of the tumor cells rather than on host-specific, tumor micro-environmental cells and factors. This can explain why existing diffuse glioma therapies fail and why these tumors have remained incurable. Thus, there is a great need for innovation. We describe a novel strategy for the development of a more effective treatment of diffuse glioma. Our approach centers on gaining control over the behavior of the microglia, the defense cells of the CNS, which are manipulated by malignant glioma and support its growth. Armoring microglia against the influences from glioma is one of our research goals. We further discuss how microglia precursors may be genetically enhanced to track down infiltrating glioma cells. PMID:24047526

Li, W; Holsinger, R M D; Kruse, C A; Flügel, A; Graeber, M B

2013-09-01

62

Post-weaning environmental enrichment alters affective responses and interacts with behavioral testing to alter nNOS immunoreactivity.  

PubMed

Challenging early life events can dramatically affect mental health and wellbeing. Childhood trauma and neglect can increase the risk for developing depressive, anxiety, and substance abuse disorders. Early maternal separation in rodents has been extensively studied and induces long-lasting alterations in affective and stress responses. However, other developmental periods (e.g., the pubertal period) comprise a critical window whereby social and environmental complexity can exert lasting changes on the brain and behavior. In this study, we tested whether early life environmental complexity impacts affective responses, aggressive behaviors, and expression of neuronal nitric oxide synthase (nNOS), the synthetic enzyme for nitric oxide, in adulthood. Mice were weaned into social+nonsocial enrichment, social only enrichment, or standard (isolated) laboratory environments and were tested in open field, elevated plus maze, forced swim, and resident-intruder aggression tests 60 days later. Social+nonsocial enrichment reduced locomotor behavior and anxiety-like responses in the open field and reduced depressive-like responses in the forced swim test. Social housing increased open arm exploration in the elevated plus maze. Both social+nonsocial enrichment and social housing only reduced aggressive behaviors compared with isolation. Social+nonsocial enrichment also increased body mass gain throughout the study. Finally, socially-housed mice had reduced corticosterone concentrations compared with social+nonsocial-enriched mice. Behavioral testing reduced nNOS-positive neurons in the basolateral amygdala and the ventral lateral septum, but not in the social+nonsocial-enriched mice, suggesting that environmental complexity may buffer the brain against some environmental perturbations. PMID:21777607

Workman, Joanna L; Fonken, Laura K; Gusfa, James; Kassouf, Kathleen M; Nelson, Randy J

2011-07-18

63

Genetic Alterations of the WT1 Gene in Papillary Serous Carcinoma of the Peritoneum  

Microsoft Academic Search

Objective. The Wilms' tumor (WT1) gene product is consistently detectable in both normal ovarian germinal epithelium and human mesothelium. Ovarian carcinomas frequently exhibit alterations in WT1 function. Papillary serous carcinoma of the peritoneum (PSCP) is believed to develop de novo from the peritoneal lining (mesothelium) of the pelvis and abdomen. The purpose of this study was to determine if genetic

John O. Schorge; Yvette B. Miller; Lai-Jun Qi; Michael G. Muto; William R. Welch; Ross S. Berkowitz; Samuel C. Mok

2000-01-01

64

Genetic variations alter production and behavioral responses following heat stress in two strains of laying hens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Heat stress is a problem for both egg production and hen well-being. Given a stressor, genetic differences alter the type and degree of hens’ responses and their adaptation. This study examined heat stress responses of two strains of White Leghorns: Dekalb XL (DXL), a commercial strain individually ...

65

Verbal fluency deficits and altered lateralization of language brain areas in individuals genetically predisposed to schizophrenia  

Microsoft Academic Search

Alterations of verbal fluency may correlate with deficits of gray matter volume and hemispheric lateralization of language brain regions like the pars triangularis (PT) in schizophrenia. Examining non-psychotic individuals at high genetic risk (HR) for schizophrenia may clarify if these deficits represent heritable trait markers or state dependent phenomena. We assessed adolescent and young adult HR subjects (N=60) and healthy

Tejas S Bhojraj; Alan N Francis; Rajaprabhakaran Rajarethinam; Shaun Eack; Shreedhar Kulkarni; Konasale M Prasad; Debra M Montrose; Diana Dworakowski; Vaibhav Diwadkar; Matcheri S Keshavan

2009-01-01

66

Analysis of genetic alterations in uterine leiomyomas and leiomyosarcomas by comparative genomic hybridization.  

PubMed

Uterine leiomyomas are the most prevalent tumor type in women of reproductive age and are the most common reason for hysterectomies. Although uterine leiomyomas are considered to be benign, they are a major public health concern for women. In contrast, leiomyosarcomas are rare but highly malignant uterine tumors. They may arise in uteri with preexisting leiomyomas and histologically sometimes resemble leiomyomas, thus causing controversy about whether leiomyosarcomas arise within leiomyomas. In this study, we used comparative genomic hybridization (CGH) to identify genetic alterations unique to each tumor type and alterations that are common between the two tumors. We analyzed 14 cases of uterine leiomyomas and eight cases of uterine leiomyosarcomas. Only two of the 14 leiomyomas exhibited genetic alterations, and those were restricted to gains on chromosomes 14 and 19 and losses on chromosomes 1 and 4. In addition, 68 leiomyomas were examined for loss of heterozygosity on chromosomes 1 and 4, and only three tumors exhibited any losses. In contrast, all eight leiomyosarcomas showed gains and losses of DNA by CGH, and in many cases multiple changes were observed. The most commonly observed genetic aberration, occurring in five tumors, was gains on both arms of chromosome 1, suggesting that this chromosome contains loci involved in the development of leiomyosarcoma. Our results do not provide evidence for the progression from benign leiomyoma to malignant leiomyosarcoma. Moreover, the large number of random chromosomal alterations in the leiomyosarcomas suggests that increased genetic instability plays a role in the formation of these tumors. PMID:9290705

Packenham, J P; du Manoir, S; Schrock, E; Risinger, J I; Dixon, D; Denz, D N; Evans, J A; Berchuck, A; Barrett, J C; Devereux, T R; Ried, T

1997-08-01

67

DNA Fingerprinting Techniques for the Analysis of Genetic and Epigenetic Alterations in Colorectal Cancer  

PubMed Central

Genetic somatic alterations are fundamental hallmarks of cancer. In addition to point and other small mutations targeting cancer genes, solid tumors often exhibit aneuploidy as well as multiple chromosomal rearrangements of large fragments of the genome. Whether somatic chromosomal alterations and aneuploidy are a driving force or a mere consequence of tumorigenesis remains controversial. Recently it became apparent that not only genetic but also epigenetic alterations play a major role in carcinogenesis. Epigenetic regulation mechanisms underlie the maintenance of cell identity crucial for development and differentiation. These epigenetic regulatory mechanisms have been found substantially altered during cancer development and progression. In this review, we discuss approaches designed to analyze genetic and epigenetic alterations in colorectal cancer, especially DNA fingerprinting approaches to detect changes in DNA copy number and methylation. DNA fingerprinting techniques, despite their modest throughput, played a pivotal role in significant discoveries in the molecular basis of colorectal cancer. The aim of this review is to revisit the fingerprinting technologies employed and the oncogenic processes that they unveiled.

Samuelsson, Johanna K.; Alonso, Sergio; Yamamoto, Fumiichiro; Perucho, Manuel

2010-01-01

68

Arachidonic Acid Metabolism in Brain Physiology and Pathology: Lessons from Genetically Altered Mouse Models  

PubMed Central

The arachidonic acid (AA) cascade involves the release of AA from the membrane phospholipids by a phospholipase A2 (PLA2), followed by its subsequent metabolism to bioactive prostanoids by cyclooxygenases (COX) coupled with terminal synthases. Altered brain AA metabolism has been implicated in neurological, neurodegenerative and psychiatric disorders. The development of genetically altered mice lacking specific enzymes of the AA cascade has helped to elucidate the individual roles of these enzymes in brain physiology and pathology. The roles of AA and its metabolites in brain physiology, with a particular emphasis on the PLA2 /COX pathway, are summarized, and the specific phenotypes of genetically altered mice relevant to brain physiology and neurotoxic models are discussed.

Bosetti, Francesca

2007-01-01

69

Torn at the Genes One Family's Debate Over Genetically Altered Plants  

NSDL National Science Digital Library

The setting for this case is the family dinner table, where a heated discussion about genetically altered foods is taking place. Marsha Cumberland’s brother-in-law has joined the family for dinner. Ed is an industry official whose job it is to decide whether or not new products need pre-market approval by the FDA. He has just returned from a conference on transgenic foods.  When it turns out that some of the food on the dinner table is genetically modified, a debate ensues with different members of the family at different ends of the spectrum. Written for an introductory biology course, the case considers the scientific and ethical issues of genetically altered plants.

Nelson, Jennifer; Herreid, Clyde F.

2000-01-01

70

Identification of differential broodstock contribution affecting genetic variability in hatchery stocks of Atlantic salmon ( Salmo salar)  

Microsoft Academic Search

Supportive breeding of Atlantic salmon (Salmo salar) is commonly employed to maintain numbers of fish where the species has become locally endangered. Increasingly, one of the main aims of population management is the preservation of natural genetic diversity. If the stocks employed in supportive breeding exhibit reduced variation they can alter the natural pattern of genetic variation observed in wild

Jose L. Horreo; Gonzalo Machado-Schiaffino; Andrew Griffiths; Dylan Bright; Jamie Stevens; Eva Garcia-Vazquez

2008-01-01

71

Genetic epidemiologic studies of affective disorders in childhood and adolescence  

Microsoft Academic Search

Summary The application of the methods of genetic epidemiology appears to be one of the most promising avenues to unravel the complex mechanisms through which genes may exert their influence. The approaches of genetic epidemiology are particularly important for those diseases which are characterized by moderate degrees of heritability and lack of direct correspondence between the underlying vulnerability factors and

Kathleen Ries Merikangas

1993-01-01

72

Genetic Screens for Mutations Affecting Development of Xenopus tropicalis  

Microsoft Academic Search

We present here the results of forward and reverse genetic screens for chemically-induced mutations in Xenopus tropicalis. In our forward genetic screen, we have uncovered 77 candidate phenotypes in diverse organogenesis and differentiation processes. Using a gynogenetic screen design, which minimizes time and husbandry space expenditures, we find that if a phenotype is detected in the gynogenetic F2 of a

Tadahiro Goda; Anita Abu-Daya; Samantha Carruthers; Matthew D. Clark; Derek L. Stemple; Lyle B. Zimmerman

2006-01-01

73

Toward altering milk composition by genetic manipulation: current status and challenges.  

PubMed

The implementation of large-scale genome mapping and sequencing has improved the understanding of animal genetics. A large number of gene sequences are now available to serve as regulatory elements or genes of interest. Although the central thrust of this work is focused on understanding disease states, the manipulation of normal metabolic processes is feasible. To date, the genetic manipulation of livestock has been limited to the permanent addition of genes of clinical interest. This study explores the utility of genetically engineered cattle as a means of altering milk composition to improve the functional properties of milk, increasing marketability. Improvements would include increasing the concentration of valuable components in milk (e.g., casein), removing undesirable components (e.g., lactose), or altering composition to resemble that of human milk as a means of improving human neonatal nutrition. The protracted time lines of genetically modifying dairy cattle has prompted the development of animal models. A model for dwarf goats is discussed in terms of circumventing the lengthy time lines involved in generating transgenic cattle and allowing for an accelerated expansion of research in molecular genetics of dairy animals. Thus, the genetic manipulation of dairy cattle is feasible and could have significant impacts on milk quality, attributes of novel dairy products, and human health. PMID:9313168

Karatzas, C N; Turner, J D

1997-09-01

74

Dim light at night interacts with intermittent hypoxia to alter cognitive and affective responses.  

PubMed

Obstructive sleep apnea (OSA) and dim light at night (dLAN) have both been independently associated with alterations in mood and cognition. We aimed to determine whether dLAN would interact with intermittent hypoxia (IH), a condition characteristic of OSA, to alter the behavioral, cognitive, and affective responses. Adult male mice were housed in either standard lighting conditions (14:10-h light-dark cycle; 150 lux:0 lux) or dLAN (150 lux:5 lux). Mice were then exposed to IH (15 cycles/h, 8 h/day, FiO2 nadir of 5%) for 3 wk, then tested in assays of affective and cognitive responses; brains were collected for dendritic morphology and PCR analysis. Exposure to dLAN and IH increased anxiety-like behaviors, as assessed in the open field, elevated plus maze, and the light/dark box. dLAN and IH increased depressive-like behaviors in the forced swim test. IH impaired learning and memory performance in the passive avoidance task; however, no differences were observed in spatial working memory, as assessed by y-maze or object recognition. IH combined with dLAN decreased cell body area in the CA1 and CA3 regions of the hippocampus. Overall, IH decreased apical spine density in the CA3, whereas dLAN decreased spine density in the CA1 of the hippocampus. TNF-? gene expression was not altered by IH or lighting condition, whereas VEGF expression was increased by dLAN. The combination of IH and dLAN provokes negative effects on hippocampal dendritic morphology, affect, and cognition, suggesting that limiting nighttime exposure to light in combination with other established treatments may be of benefit to patients with OSA. PMID:23657638

Aubrecht, Taryn G; Weil, Zachary M; Magalang, Ulysses J; Nelson, Randy J

2013-05-08

75

Genetic interactions between polymorphisms that affect gene expression in yeast  

PubMed Central

Interactions between polymorphisms at different quantitative trait loci (QTLs) are thought to contribute to the genetics of many traits, and can dramatically impact the power of genetic studies to detect QTLs1. Interacting loci have been identified in many organisms1–5. However, the prevalence of interactions6–8, and the nucleotide changes underlying them9,10, are largely unknown. Here we search for naturally occurring genetic interactions in a large set of quantitative phenotypes—the levels of all transcripts in a cross between two strains of S. cerevisiae7. For each transcript, we searched for secondary loci that interact with primary QTLs detected by their individual effects. Such locus pairs were estimated to play a role in the inheritance of 57% of transcripts; statistically significant pairs were identified for 225 transcripts. Among these, 67% of secondary loci had individual effects too small to be significant in a genome-wide scan. Engineered polymorphisms in isogenic strains confirmed an interaction between the mating-type locus MAT and the pheromone response gene GPA1. Our results suggest that genetic interactions are widespread in the genetics of transcript levels, and that many QTLs will be missed by single-locus tests but can be detected by two-stage tests that allow for interactions.

Brem, Rachel B.; Storey, John D.; Whittle, Jacqueline; Kruglyak, Leonid

2005-01-01

76

Tissue culture-induced genetic and epigenetic alterations in rice pure-lines, F1 hybrids and polyploids  

PubMed Central

Background Genetic and epigenetic alterations can be invoked by plant tissue culture, which may result in heritable changes in phenotypes, a phenomenon collectively termed somaclonal variation. Although extensive studies have been conducted on the molecular nature and spectrum of tissue culture-induced genomic alterations, the issue of whether and to what extent distinct plant genotypes, e.g., pure-lines, hybrids and polyploids, may respond differentially to the tissue culture condition remains poorly understood. Results We investigated tissue culture-induced genetic and epigenetic alterations in a set of rice genotypes including two pure-lines (different subspecies), a pair of reciprocal F1 hybrids parented by the two pure-lines, and a pair of reciprocal tetraploids resulted from the hybrids. Using two molecular markers, amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP), both genetic and DNA methylation alterations were detected in calli and regenerants from all six genotypes, but genetic alteration is more prominent than epigenetic alteration. While significant genotypic difference was observed in frequencies of both types of alterations, only genetic alteration showed distinctive features among the three types of genomes, with one hybrid (N/9) being exceptionally labile. Surprisingly, difference in genetic alteration frequencies between the pair of reciprocal F1 hybrids is much greater than that between the two pure-line subspecies. Difference also exists in the pair of reciprocal tetraploids, but is to a less extent than that between the hybrids. The steady-state transcript abundance of genes involved in DNA repair and DNA methylation was significantly altered in both calli and regenerants, and some of which were correlated with the genetic and/or epigenetic alterations. Conclusions Our results, based on molecular marker analysis of ca. 1,000 genomic loci, document that genetic alteration is the major cause of somaclonal variation in rice, which is concomitant with epigenetic alterations. Perturbed expression by tissue culture of a set of 41 genes encoding for enzymes involved in DNA repair and DNA methylation is associated with both genetic and epigenetic alterations. There exist fundamental differences among distinct genotypes, pure-lines, hybrids and tetraploids, in propensities of generating both genetic and epigenetic alterations under the tissue culture condition. Parent-of-origin has a conspicuous effect on the alteration frequencies.

2013-01-01

77

Altering SARS Coronavirus Frameshift Efficiency Affects Genomic and Subgenomic RNA Production  

PubMed Central

In previous studies, differences in the amount of genomic and subgenomic RNA produced by coronaviruses with mutations in the programmed ribosomal frameshift signal of ORF1a/b were observed. It was not clear if these differences were due to changes in genomic sequence, the protein sequence or the frequency of frameshifting. Here, viruses with synonymous codon changes are shown to produce different ratios of genomic and subgenomic RNA. These findings demonstrate that the protein sequence is not the primary cause of altered genomic and subgenomic RNA production. The synonymous codon changes affect both the structure of the frameshift signal and frameshifting efficiency. Small differences in frameshifting efficiency result in dramatic differences in genomic RNA production and TCID50 suggesting that the frameshifting frequency must stay above a certain threshold for optimal virus production. The data suggest that either the RNA sequence or the ratio of viral proteins resulting from different levels of frameshifting affects viral replication.

Plant, Ewan P.; Sims, Amy C.; Baric, Ralph S.; Dinman, Jonathan D.; Taylor, Deborah R.

2013-01-01

78

Genetic background affects susceptibility to tumoral stem cell reprogramming.  

PubMed

The latest studies of the interactions between oncogenes and its target cell have shown that certain oncogenes may act as passengers to reprogram tissue-specific stem/progenitor cell into a malignant cancer stem cell state. In this study, we show that the genetic background influences this tumoral stem cell reprogramming capacity of the oncogenes using as a model the Sca1-BCRABLp210 mice, where the type of tumor they develop, chronic myeloid leukemia (CML), is a function of tumoral stem cell reprogramming. Sca1-BCRABLp210 mice containing FVB genetic components were significantly more resistant to CML. However, pure Sca1-BCRABLp210 FVB mice developed thymomas that were not seen in the Sca1-BCRABLp210 mice into the B6 background. Collectively, our results demonstrate for the first time that tumoral stem cell reprogramming fate is subject to polymorphic genetic control. PMID:23839033

García-Ramírez, Idoia; Ruiz-Roca, Lucía; Martín-Lorenzo, Alberto; Blanco, Oscar; García-Cenador, María Begoña; García-Criado, Francisco Javier; Vicente-Dueñas, Carolina; Sánchez-García, Isidro

2013-07-08

79

Alterations in expression levels of deafness dystonia protein 1 affect mitochondrial morphology.  

PubMed

Deafness-Dystonia-Optic Neuropathy (DDON) Syndrome is a rare X-linked progressive neurodegenerative disorder resulting from mutations in the TIMM8A gene encoding for the deafness dystonia protein 1 (DDP1). Despite important progress in identifying and characterizing novel mutations in this gene, little is known about the underlying pathomechanisms. Deficiencies in the biogenesis of hTim23 and consecutive alterations in biogenesis of inner membrane and matrix proteins have been proposed to serve as one possible mechanistic explanation. To shed new light on the role of DDP1 in the biogenesis of mammalian mitochondria, we investigated the effects of reduced or elevated DDP1 levels on mitochondrial dynamics and function. Our results show a reduction in the import of ?-barrel proteins into mitochondria from cells overexpressing DDP1. This effect was not observed when the DDON-related mutant form DDP1-C66W was overexpressed. Live cell microscopy of primary fibroblasts derived from DDON patients and of DDP1 downregulated HeLa cells displayed alterations of mitochondrial morphology with notable extensions in the length of mitochondrial tubules, whereas overexpression of DDP1 induced the formation of hollow spherical mitochondria. Of note, knockdown of the TIMM8A gene by RNA interference did not show an influence on the oxygen respiration rate and the mitochondrial membrane potential. Taken together, these results suggest that alterations in the levels of DDP1 can affect the morphology of mitochondria and thus shed new light on the pathogenic mechanisms of DDON. PMID:21984432

Engl, Gertraud; Florian, Stefan; Tranebjærg, Lisbeth; Rapaport, Doron

2011-10-07

80

Naturally occurring genetic variation affects Drosophila photoreceptor determination  

Microsoft Academic Search

The signal transduction pathway controlling determination of the identity of the R7 photoreceptor in the Drosophila eye is shown to harbor high levels of naturally occurring genetic variation. The number of ectopic R7 cells induced by the\\u000a dosage-sensitive Sev\\u000a \\u000a S11.1\\u000a transgene that encodes a mildly activated form of the Sevenless tyrosine kinase receptor is highly sensitive to the wild-type\\u000a genetic

Patricia J. Polaczyk; Robert Gasperini; Greg Gibson

1998-01-01

81

Genetic Alterations in Goblet Cell Carcinoids of the Vermiform Appendix and Comparison with Gastrointestinal Carcinoid Tumors  

Microsoft Academic Search

Goblet cell carcinoid is a relatively rare neuroendocrine tumor of the vermiform appendix with poorly understood molecular pathogenesis. We studied the clinicopathologic features and genetic alterations, including allelic loss of chromosomes 11q, 16q, and 18q; sequencing of the K-ras, ?-catenin, and DPC4 (SMAD4) genes; and p53 overexpression and loss of DPC4 by immunohistochemistry; in 16 goblet cell carcinoids. We compared

Mirela Stancu; Tsung-Teh Wu; Charita Wallace; Patrick S Houlihan; Asif Rashid

2003-01-01

82

Genetic alterations associated with the evolution and progression of astrocytic brain tumours  

Microsoft Academic Search

Diffusely infiltrating low-grade astrocytomas (WHO grade II) have an intrinsic tendency for progression to anaplastic astrocytoma (WHO grade III) and glioblastoma (WHO grade IV). This change is due to the sequential acquisition of genetic alterations, several of which have recently been identified. In low-grade astrocytomas, p53 mutations with or without loss of heterozygosity on chromosome 17p are the principal detectable

H. Ohgaki; P. Kleihues; B. Schäuble; A. Hausen; K. Ammon

1995-01-01

83

Alterations in the Endogenous Ascorbic Acid Content Affect Flowering Time in Arabidopsis1[W][OA  

PubMed Central

Ascorbic acid (AA) protects plants against abiotic stress. Previous studies suggested that this antioxidant is also involved in the control of flowering. To decipher how AA influences flowering time, we studied the four AA-deficient Arabidopsis (Arabidopsis thaliana) mutants vtc1-1, vtc2-1, vtc3-1, and vtc4-1 when grown under short and long days. These mutants flowered and senesced before the wild type irrespective of the photoperiod, a response that cannot simply be attributed to slightly elevated oxidative stress in the mutants. Transcript profiling of various flowering pathway genes revealed a correlation of altered mRNA levels and flowering time. For example, circadian clock and photoperiodic pathway genes were significantly higher in the vtc mutants than in the wild type under both short and long days, a result that is consistent with the early-flowering phenotype of the mutants. In contrast, when the AA content was artificially increased, flowering was delayed, which correlated with lower mRNA levels of circadian clock and photoperiodic pathway genes compared with plants treated with water. Similar observations were made for the autonomous pathway. Genetic analyses demonstrated that various photoperiodic and autonomous pathway mutants are epistatic to the vtc1-1 mutant. In conclusion, our transcript and genetic analyses suggest that AA acts upstream of the photoperiodic and autonomous pathways.

Kotchoni, Simeon O.; Larrimore, Katherine E.; Mukherjee, Madhumati; Kempinski, Chase F.; Barth, Carina

2009-01-01

84

Genetic variations alter production and behavioral responses following heat stress in 2 strains of laying hens.  

PubMed

Genetic differences alter the type and degree of hens' responses and their ability to adapt to a stressor. This study examined the effects of genotypic variations on the productivity and behavior of laying hens following heat stress (HS). Two strains of White Leghorn hens were used: DXL (Dekalb XL), a commercial strain individually selected for egg production and KGB (kind, gentle bird), a strain selected for high group productivity and survivability. Ninety hens (48 DXL and 42 KGB) at 28 wk of age were randomly assigned to either a hot (H: mean = 32.6°C) or control (C: mean = 24.3°C) treatment and housed in pairs by strain for 9 d. Egg production and quality, behavior, body and organ weights, and circulating hormone concentrations were measured. Heat-stressed hens had lower egg production [adjusted (adj) P < 0.001] than their respective controls. Among H-DXL hens, egg weight tended to be reduced at d 1 and was reduced at d 9 (adj P = 0.007), but was reduced only at d 9 among H-KGB hens (adj P = 0.007). Eggshell thickness was also reduced among H hens at d 9 (adj P = 0.007), especially among H-KGB hens (adj P = 0.01). Plasma triiodothyronine concentration was reduced among H-hens (adj P = 0.01), especially among H-DXL hens (adj P = 0.01). Neither temperature nor strain affected the plasma thyroxine and plasma and yolk corticosterone concentrations. Heat-stressed hens spent less time walking (adj P = 0.001) and more time drinking (adj P = 0.007) and resting (adj P = 0.001) than C-hens. The results indicate that although HS reduced production and caused behavioral changes among hens from both strains, the responses differed by genotype. The data provide evidence that genetic selection is a useful strategy for reducing HS response in laying hens. The results provide insights for conducting future studies to develop heat-resistant strains to improve hen well-being, especially under the current commercial conditions. PMID:23300291

Mack, L A; Felver-Gant, J N; Dennis, R L; Cheng, H W

2013-02-01

85

Reversion of a fungal genetic code alteration links proteome instability with genomic and phenotypic diversification.  

PubMed

Many fungi restructured their proteomes through incorporation of serine (Ser) at thousands of protein sites coded by the leucine (Leu) CUG codon. How these fungi survived this potentially lethal genetic code alteration and its relevance for their biology are not understood. Interestingly, the human pathogen Candida albicans maintains variable Ser and Leu incorporation levels at CUG sites, suggesting that this atypical codon assignment flexibility provided an effective mechanism to alter the genetic code. To test this hypothesis, we have engineered C. albicans strains to misincorporate increasing levels of Leu at protein CUG sites. Tolerance to the misincorporations was very high, and one strain accommodated the complete reversion of CUG identity from Ser back to Leu. Increasing levels of Leu misincorporation decreased growth rate, but production of phenotypic diversity on a phenotypic array probing various metabolic networks, drug resistance, and host immune cell responses was impressive. Genome resequencing revealed an increasing number of genotype changes at polymorphic sites compared with the control strain, and 80% of Leu misincorporation resulted in complete loss of heterozygosity in a large region of chromosome V. The data unveil unanticipated links between gene translational fidelity, proteome instability and variability, genome diversification, and adaptive phenotypic diversity. They also explain the high heterozygosity of the C. albicans genome and open the door to produce microorganisms with genetic code alterations for basic and applied research. PMID:23776239

Bezerra, Ana R; Simões, João; Lee, Wanseon; Rung, Johan; Weil, Tobias; Gut, Ivo G; Gut, Marta; Bayés, Mónica; Rizzetto, Lisa; Cavalieri, Duccio; Giovannini, Gloria; Bozza, Silvia; Romani, Luigina; Kapushesky, Misha; Moura, Gabriela R; Santos, Manuel A S

2013-06-17

86

Signs of Selective Pressure on Genetic Variants Affecting Human Height  

Microsoft Academic Search

Many decades of scientific investigation have proved the role of selective pressure in Homo Sapiens at least at the level of individual genes or loci. Nevertheless, there are examples of polygenic traits that are bound to be under selection, but studies devoted to apply population genetics methods to unveil such occurrence are still lacking. Stature provides a relevant example of

Roberto Amato; Gennaro Miele; Antonella Monticelli; Sergio Cocozza

2011-01-01

87

Analysis of genetic factors affecting egg production in Drosophila melanogaster  

Microsoft Academic Search

Genetic determinants of egg production were studied in two inbred lines of Drosophila melanogaster. Chromosome III was the only one responsible for differences in egg laying between them; its effect is completely dominant. By means of a marker stock, synthetic chromosomes were constructed consisting of known portions of the two third chromosomes but without carrying any marker genes themselves. Chromosome

A Dominguez; J Rubio

1986-01-01

88

Progress in detecting genetic alterations and their association with human disease.  

PubMed

The completion of the Human Genome Project provided a reference sequence to which researchers could compare sequences from individual patients in the hope of identifying disease-causing mutations. However, this still necessitated candidate gene testing or a very limited screen of multiple genes using Sanger sequencing. With the advent of high-throughput Sanger sequencing, it became possible to screen hundreds of patients for alterations in hundreds of genes. This process was time consuming and limited to a few locations/institutions that had the space to house tens of sequencing equipment. The development of next generation sequencing revolutionized the process. It is now feasible to sequence the entire exome of multiple individuals in about 10 days. However, this meant that a massive amount of data needed to be filtered to identify the relevant alteration. This is presently the rate-limiting step in providing a convincing association between a genetic alteration and a human disorder. PMID:23876707

Schwartz, Charles E; Chen, Chin-Fu

2013-07-20

89

Genetic alterations activating kinase and cytokine receptor signaling in high-risk acute lymphoblastic leukemia  

PubMed Central

SUMMARY Genomic profiling has identified a subtype of high-risk B-progenitor acute lymphoblastic leukemia (B-ALL) with alteration of IKZF1, a gene expression profile similar to BCR-ABL1-positive ALL and poor outcome (Ph-like ALL). The genetic alterations that activate kinase signaling in Ph-like ALL are poorly understood. We performed transcriptome and whole genome sequencing on 15 cases of Ph-like ALL, and identified rearrangements involving ABL1, JAK2, PDGFRB, CRLF2 and EPOR, activating mutations of IL7R and FLT3, and deletion of SH2B3, which encodes the JAK2 negative regulator LNK. Importantly, several of these alterations induce transformation that is attenuated with tyrosine kinase inhibitors, suggesting the treatment outcome of these patients may be improved with targeted therapy.

Roberts, Kathryn G.; Morin, Ryan D.; Zhang, Jinghui; Hirst, Martin; Zhao, Yongjun; Su, Xiaoping; Chen, Shann-Ching; Payne-Turner, Debbie; Churchman, Michelle; Harvey, Richard C.; Chen, Xiang; Kasap, Corynn; Yan, Chunhua; Becksfort, Jared; Finney, Richard P.; Teachey, David T.; Maude, Shannon L.; Tse, Kane; Moore, Richard; Jones, Steven; Mungall, Karen; Birol, Inanc; Edmonson, Michael N.; Hu, Ying; Buetow, Kenneth E.; Chen, I-Ming; Carroll, William L.; Wei, Lei; Ma, Jing; Kleppe, Maria; Levine, Ross L.; Garcia-Manero, Guillermo; Larsen, Eric; Shah, Neil P.; Devidas, Meenakshi; Reaman, Gregory; Smith, Malcolm; Paugh, Steven W.; Evans, William E.; Grupp, Stephan A.; Jeha, Sima; Pui, Ching-Hon; Gerhard, Daniela S.; Downing, James R.; Willman, Cheryl L.; Loh, Mignon; Hunger, Stephen P.; Marra, Marco; Mullighan, Charles G.

2012-01-01

90

Genetic effects in Drosophila on the potency of diverse general anesthetics: a distinctive pattern of altered sensitivity  

PubMed Central

Mutations that influence the sensitivity of an organism to a volatile general anesthetic can be divided into two classes. In one, sensitivity to all other volatile agents is affected to a similar degree. Although this class may contain mutations of interest for understanding anesthesia, it is also likely to contain mutations that merely alter general health. In the second class, mutations confer non-uniform effects on potency (NEP), i.e., larger effects for some volatile anesthetics than for others. Members of this class are of special interest for studies of arousal and its pharmacological suppression because they not only avoid the pitfall of effects on global health, they imply the existence of drug targets that are preferentially affected by particular agents. In this work we provide the first systematic investigation of the relative frequency and diversity of NEP mutations in Drosophila. As a first step we isolated and characterized a set of P element insertion mutations that confer altered sensitivity of the fruit fly to the clinical anesthetic halothane. Then we tested the members of this collection for their effect on the sensitivity of flies to five other volatile agents. Not only do we find that most of the mutations show non-uniform effects, they share a characteristic arrangement of altered potencies (halothane >>desflurane ? enflurane ? isoflurane ? methoxyflurane > sevoflurane). From this result, although we do not know how direct or indirect are the effects of the mutations, we infer the existence of a biologically relevant target for anesthetic action that has a distinct preference for halothane over other agents. Intriguingly, P element insertions that co-map with several NEP loci have been shown to alter the fly’s response to cocaine and ethanol, suggesting that common genetic elements are involved in the response to all three drugs.

Campbell, Joseph L.; Gu, Qun; Guo, Dongyu; Nash, Howard A.

2009-01-01

91

Genetic effects in Drosophila on the potency of diverse general anesthetics: a distinctive pattern of altered sensitivity.  

PubMed

Mutations that influence the sensitivity of an organism to a volatile general anesthetic can be divided into two classes. In one, sensitivity to all other volatile agents is affected to a similar degree. Although this class may contain mutations of interest for understanding anesthesia, it is also likely to contain mutations that merely alter general health. In the second class, mutations confer non-uniform effects on potency (NEP), i.e., larger effects for some volatile anesthetics than for others. Members of this class are of special interest for studies of arousal and its pharmacological suppression because they not only avoid the pitfall of effects on global health, but also imply the existence of drug targets that are preferentially affected by particular agents. In this work, we provide the first systematic investigation of the relative frequency and diversity of NEP mutations in Drosophila. As a first step, we isolated and characterized a set of P element insertion mutations that confer altered sensitivity of the fruit fly to the clinical anesthetic halothane. Then we tested the members of this collection for their effect on the sensitivity of flies to five other volatile agents. Not only do we find that most of the mutations show non-uniform effects, they also share a characteristic arrangement of altered potencies (halothane > >desflurane >or= enflurane approximately isoflurane approximately methoxyflurane > sevoflurane). From this result, although we do not know how direct or indirect are the effects of the mutations, we infer the existence of a biologically relevant target for anesthetic action that has a distinct preference for halothane over other agents. Intriguingly, P element insertions that co-map with several NEP loci have been shown to alter the fly's response to cocaine and ethanol, suggesting that common genetic elements are involved in the response to all three drugs. PMID:19863272

Campbell, Joseph L; Gu, Qun; Guo, Dongyu; Nash, Howard A

2009-01-01

92

Predictors of uptake of obesity genetic testing among affected adults  

Microsoft Academic Search

Given that a large number of candidate genes coding for a tendency toward obesity have been identified and some findings have\\u000a been replicated, we explored characteristics of those who would be most likely to obtain future genetic testing for this tendency.\\u000a During a series of focus groups, obese respondents rated their likelihood of obtaining testing under conditions in which either

Mary E. Segal; Marcia Polansky; Pamela Sankar

2007-01-01

93

Genetics of early onset bipolar affective disorder: are we making progress?  

PubMed

Though considerable progress has been made in understanding the molecular genetics of bipolar affective dis order, few studies are currently focusing on the genetics of prepubertal or early adolescent onset illness. A variety of studies of the phenomenology, imaging and comorbidity of early onset bipolarity find significant differences from late onset illness. These studies raise the notion that early onset cases may represent a distinct genetic form or forms of manic-depressive illness. PMID:11914176

Todd, Richard D

2002-04-01

94

Docosahexaenoic acid affects insulin deficiency- and insulin resistance-induced alterations in cardiac mitochondria.  

PubMed

The effect of docosahexaenoic acid (DHA) intake on cardiac mitochondrial function was evaluated in permeabilized fibers in insulin deficiency and insulin resistance in rats. The insulin-deficient state was obtained by streptozotocin injection 2 mo before investigations. Insulin resistance was obtained by feeding a 62% fructose diet for 3 mo. DHA was incorporated in the diet to modify the fatty acid composition of cardiac membranes, including mitochondria. Insulin deficiency decreased mitochondrial creatine kinase (mi-CK) activity and mitochondrial sensitivity to ADP. DHA intake prevented these alterations. Moreover, the insulin-deficient state significantly decreased n-3 polyunsaturated fatty acids (PUFA) and slightly increased n-6 PUFA in both cardiac and mitochondrial membranes, inducing a significant increase in the n-6-to-n-3 ratio. DHA intake maintained high myocardial and mitochondrial DHA content. Insulin deficiency also decreased glutamate- and palmitoylcarnitine-supported mitochondrial respiration, but DHA intake did not prevent these effects. In contrast, insulin resistance did not affect mi-CK activity or sensitivity to ADP. However, insulin resistance influenced the myocardial fatty acid composition with decreased n-6 and n-3 PUFA contents and increased monounsaturated fatty acid content. Only slight alterations were observed in mitochondrial fatty acid composition, and they were corrected by DHA intake. Moreover, insulin resistance decreased the glutamate-supported respiration, and DHA intake did not influence this effect. In conclusion, the impairment of cardiac mitochondrial function was more pronounced in the insulin-deficient state than in insulin resistance. The modification of fatty acid composition of cardiac and mitochondrial membranes by DHA partially prevented the mitochondrial alterations induced in the two models. PMID:14604840

Ovide-Bordeaux, Stéphanie; Grynberg, Alain

2003-11-06

95

Signs of selective pressure on genetic variants affecting human height.  

PubMed

Many decades of scientific investigation have proved the role of selective pressure in Homo Sapiens at least at the level of individual genes or loci. Nevertheless, there are examples of polygenic traits that are bound to be under selection, but studies devoted to apply population genetics methods to unveil such occurrence are still lacking. Stature provides a relevant example of well-studied polygenic trait for which is now available a genome-wide association study which has identified the genes involved in this trait, and which is known to be under selection. We studied the behavior of F(ST) in a simulated toy model to detect population differentiation on a generic polygenic phenotype under selection. The simulations showed that the set of alleles involved in the trait has a higher mean F(ST) value than those undergoing genetic drift only. In view of this we looked for an increase in the mean F(ST) value of the 180 variants associated to human height. For this set of alleles we found F(ST) to be significantly higher than the genomic background (p?=?0.0356). On the basis of a statistical analysis we excluded that the increase was just due to the presence of outliers. We also proved as marginal the role played by local adaptation phenomena, even on different phenotypes in linkage disequilibrium with genetic variants involved in height. The increase of F(ST) for the set of alleles involved in a polygenic trait seems to provide an example of symmetry breaking phenomenon concerning the population differentiation. The splitting in the allele frequencies would be driven by the initial conditions in the population dynamics which are stochastically modified by events like drift, bottlenecks, etc, and other stochastic events like the born of new mutations. PMID:22096598

Amato, Roberto; Miele, Gennaro; Monticelli, Antonella; Cocozza, Sergio

2011-11-09

96

Alteration of Soil Rhizosphere Communities following Genetic Transformation of White Spruce?  

PubMed Central

The application of plant genetic manipulations to agriculture and forestry with the aim of alleviating insect damage through Bacillus thuringiensis transformation could lead to a significant reduction in the release of pesticides into the environment. However, many groups have come forward with very valid and important questions related to potentially adverse effects, and it is crucial to assess and better understand the impact that this technology might have on ecosystems. In this study, we analyzed rhizosphere soil samples collected from the first B. thuringiensis-transformed trees [with insertion of the CryIA(b) toxin-encoding gene] grown in Canada (Val-Cartier, QC, Canada) as part of an ecological impact assessment project. Using a robust amplified rRNA gene restriction analysis approach coupled with 16S rRNA gene sequencing, the rhizosphere-inhabiting microbial communities of white spruce (Picea glauca) genetically modified by biolistic insertion of the cryIA(b), uidA (beta-glucuronidase), and nptII genes were compared with the microbial communities associated with non-genetically modified counterparts and with trees in which only the genetic marker genes uidA and nptII have been inserted. Analysis of 1,728 rhizosphere bacterial clones (576 clones per treatment) using a Cramér-von Mises statistic analysis combined with a Monte Carlo comparison clearly indicated that there was a statistically significant difference (P < 0.05) between the microbial communities inhabiting the rhizospheres of trees carrying the cryIA(b), uidA, and nptII transgenes, trees carrying only the uidA and nptII transgenes, and control trees. Clear rhizosphere microbial community alterations due to B. thuringiensis tree genetic modification have to our knowledge never been described previously and open the door to interesting questions related to B. thuringiensis genetic transformation and also to the impact of commonly used uidA and nptII genetic marker genes.

LeBlanc, Philippe M.; Hamelin, Richard C.; Filion, Martin

2007-01-01

97

Whole-genome sequencing identifies genetic alterations in pediatric low-grade gliomas  

PubMed Central

The commonest pediatric brain tumors are low-grade gliomas (LGGs). We utilized whole genome sequencing to discover multiple novel genetic alterations involving BRAF, RAF1, FGFR1, MYB, MYBL1 and genes with histone-related functions, including H3F3A and ATRX, in 39 LGGs and low-grade glioneuronal tumors (LGGNTs). Only a single non-silent somatic alteration was detected in 24/39 (62%) tumors. Intragenic duplications of the FGFR1 tyrosine kinase domain (TKD) and rearrangements of MYB were recurrent and mutually exclusive in 53% of grade II diffuse LGGs. Transplantation of Trp53-null neonatal astrocytes containing TKD-duplicated FGFR1 into brains of nude mice generated high-grade astrocytomas with short latency and 100% penetrance. TKD-duplicated FGFR1 induced FGFR1 autophosphorylation and upregulation of the MAPK/ERK and PI3K pathways, which could be blocked by specific inhibitors. Focusing on the therapeutically challenging diffuse LGGs, our study of 151 tumors has discovered genetic alterations and potential therapeutic targets across the entire range of pediatric LGGs/LGGNTs.

Zhang, Jinghui; Wu, Gang; Miller, Claudia P.; Tatevossian, Ruth G.; Dalton, James D.; Tang, Bo; Orisme, Wilda; Punchihewa, Chandanamali; Parker, Matthew; Qaddoumi, Ibrahim; Boop, Fredrick A.; Lu, Charles; Kandoth, Cyriac; Ding, Li; Lee, Ryan; Huether, Robert; Chen, Xiang; Hedlund, Erin; Nagahawatte, Panduka; Rusch, Michael; Boggs, Kristy; Cheng, Jinjun; Becksfort, Jared; Ma, Jing; Song, Guangchun; Li, Yongjin; Wei, Lei; Wang, Jianmin; Shurtleff, Sheila; Easton, John; Zhao, David; Fulton, Robert S.; Fulton, Lucinda L.; Dooling, David J.; Vadodaria, Bhavin; Mulder, Heather L.; Tang, Chunlao; Ochoa, Kerri; Mullighan, Charles G.; Gajjar, Amar; Kriwacki, Richard; Sheer, Denise; Gilbertson, Richard J.; Mardis, Elaine R.; Wilson, Richard K.; Downing, James R.; Baker, Suzanne J.; Ellison, David W.

2013-01-01

98

Genetic epidemiology of mutated K-rasproto-oncogene, altered suppressor genes, and microsatellite instability in colorectal adenomas  

Microsoft Academic Search

BACKGROUNDThe genetic epidemiology of colorectal adenomas has not been studied prospectively in colonoscopy patients without cancer.AIMSTo study genetic alterations in colorectal adenomas and correlate these with patient demographics and adenoma characteristics.METHODSMutations and allelic deletions in 201 adenomas from 60 patients were compared with demographic features, adenoma characteristics, and family history.RESULTSThe most common alteration was K-ras proto-oncogene mutation, present in 35%

A Rashid; M Zahurak; S N Goodman; S R Hamilton

1999-01-01

99

Alteration of fatty-acid-metabolizing enzymes affects mitochondrial form and function in hereditary spastic paraplegia.  

PubMed

Hereditary spastic paraplegia (HSP) is considered one of the most heterogeneous groups of neurological disorders, both clinically and genetically. The disease comprises pure and complex forms that clinically include slowly progressive lower-limb spasticity resulting from degeneration of the corticospinal tract. At least 48 loci accounting for these diseases have been mapped to date, and mutations have been identified in 22 genes, most of which play a role in intracellular trafficking. Here, we identified mutations in two functionally related genes (DDHD1 and CYP2U1) in individuals with autosomal-recessive forms of HSP by using either the classical positional cloning or a combination of whole-genome linkage mapping and next-generation sequencing. Interestingly, three subjects with CYP2U1 mutations presented with a thin corpus callosum, white-matter abnormalities, and/or calcification of the basal ganglia. These genes code for two enzymes involved in fatty-acid metabolism, and we have demonstrated in human cells that the HSP pathophysiology includes alteration of mitochondrial architecture and bioenergetics with increased oxidative stress. Our combined results focus attention on lipid metabolism as a critical HSP pathway with a deleterious impact on mitochondrial bioenergetic function. PMID:23176821

Tesson, Christelle; Nawara, Magdalena; Salih, Mustafa A M; Rossignol, Rodrigue; Zaki, Maha S; Al Balwi, Mohammed; Schule, Rebecca; Mignot, Cyril; Obre, Emilie; Bouhouche, Ahmed; Santorelli, Filippo M; Durand, Christelle M; Oteyza, Andrés Caballero; El-Hachimi, Khalid H; Al Drees, Abdulmajeed; Bouslam, Naima; Lamari, Foudil; Elmalik, Salah A; Kabiraj, Mohammad M; Seidahmed, Mohammed Z; Esteves, Typhaine; Gaussen, Marion; Monin, Marie-Lorraine; Gyapay, Gabor; Lechner, Doris; Gonzalez, Michael; Depienne, Christel; Mochel, Fanny; Lavie, Julie; Schols, Ludger; Lacombe, Didier; Yahyaoui, Mohamed; Al Abdulkareem, Ibrahim; Zuchner, Stephan; Yamashita, Atsushi; Benomar, Ali; Goizet, Cyril; Durr, Alexandra; Gleeson, Joseph G; Darios, Frederic; Brice, Alexis; Stevanin, Giovanni

2012-11-21

100

Alterations in seed development gene expression affect size and oil content of Arabidopsis seeds.  

PubMed

Seed endosperm development in Arabidopsis (Arabidopsis thaliana) is under control of the polycomb group complex, which includes Fertilization Independent Endosperm (FIE). The polycomb group complex regulates downstream factors, e.g. Pheres1 (PHE1), by genomic imprinting. In heterozygous fie mutants, an endosperm develops in ovules carrying a maternal fie allele without fertilization, finally leading to abortion. Another endosperm development pathway depends on MINISEED3 (a WRKY10 transcription factor) and HAIKU2 (a leucine-rich repeat kinase). While the role of seed development genes in the embryo and endosperm establishment has been studied in detail, their impact on metabolism and oil accumulation remained unclear. Analysis of oil, protein, and sucrose accumulation in mutants and overexpression plants of the four seed development genes revealed that (1) seeds carrying a maternal fie allele accumulate low oil with an altered composition of triacylglycerol molecular species; (2) homozygous mutant seeds of phe1, mini3, and iku2, which are smaller, accumulate less oil and slightly less protein, and starch, which accumulates early during seed development, remains elevated in mutant seeds; (3) embryo-specific overexpression of FIE, PHE1, and MINI3 has no influence on seed size and weight, nor on oil, protein, or sucrose content; and (4) overexpression of IKU2 results in seeds with increased size and weight, and oil content of overexpressed IKU2 seeds is increased by 35%. Thus, IKU2 overexpression represents a novel strategy for the genetic manipulation of the oil content in seeds. PMID:24014578

Fatihi, Abdelhak; Zbierzak, Anna Maria; Dörmann, Peter

2013-09-06

101

Molecular genetic alterations in gliomatosis cerebri: What can we learn about the origin and course of the disease?  

Microsoft Academic Search

Gliomatosis cerebri (GC) is a neuroepithelial neoplasm with extensive infiltration of large parts of the brain. Recent data showing the involvement of TP53 mutation or nuclear protein accumulation in some cases have linked the astrocytic phenotype of the tumor cells to TP53 alterations frequently found in common astrocytomas. However, the frequency of these alterations is low, and other molecular genetic

Christian Mawrin

2005-01-01

102

Tumor Derived Mutations of Protein Tyrosine Phosphatase Receptor Type K Affect Its Function and Alter Sensitivity to Chemotherapeutics in Glioma  

PubMed Central

Poor prognosis and resistance to therapy in malignant gliomas is mainly due to the highly dispersive nature of glioma cells. This dispersive characteristic results from genetic alterations in key regulators of cell migration and diffusion. A better understanding of these regulatory signals holds promise to improve overall survival and response to therapy. Using mapping arrays to screen for genomic alterations in gliomas, we recently identified alterations of the protein tyrosine phosphatase receptor type kappa gene (PTPRK) that correlate to patient outcomes. These PTPRK alterations are very relevant to glioma biology as PTPRK can directly sense cell–cell contact and is a dephosphorylation regulator of tyrosine phosphorylation signaling, which is a major driving force behind tumor development and progression. Subsequent sequencing of the full length PTPRK transcripts revealed novel PTPRK gene deletion and missense mutations in numerous glioma biopsies. PTPRK mutations were cloned and expressed in PTPRK-null malignant glioma cells. The effect of these mutations on PTPRK anti-oncogenic function and their association with response to anti-glioma therapeutics, such as temozolomide and tyrosine kinase inhibitors, was subsequently analyzed using in vitro cell-based assays. These genetic variations altered PTPRK activity and its post-translational processing. Reconstitution of wild-type PTPRK in malignant glioma cell lines suppressed cell growth and migration by inhibiting EGFR and ?-catenin signaling and improved the effect of conventional therapies for glioma. However, PTPRK mutations abrogated tumor suppressive effects of wild-type PTPRK and altered sensitivity of glioma cells to chemotherapy.

Agarwal, Supreet; Al-Keilani, Maha S.; Alqudah, Mohammad A. Y.; Sibenaller, Zita A.; Ryken, Timothy C.; Assem, Mahfoud

2013-01-01

103

Genetic modification of lignin concentration affects fitness of perennial herbaceous plants.  

PubMed

Populations of four perennial herbaceous species that were genetically modified for altered lignin content (or associated forage digestibility) by conventional plant breeding were evaluated for two agricultural fitness traits, plant survival and plant biomass, in three Northcentral USA environments for more than 4 years. Reduced lignin concentration or increased digestibility resulted in increased winter mortality in two of four species and reduced biomass in one species. Results from other experiment indicate that these apparent genetic correlations may be ephemeral, suggesting that selection for fitness can be successful within high-digestibility or low-lignin germplasm. Results indicate that perennial plants genetically engineered with altered lignin concentration or composition for use in livestock, pulp and paper, or bioenergy production should be evaluated for fitness in field environments prior to use in agriculture. PMID:12579437

Casler, M D; Buxton, D R; Vogel, K P

2002-01-01

104

Genetic Background Affects Properties of Satellite Cells and mdx Phenotypes  

PubMed Central

Duchenne muscular dystrophy (DMD) is the most common lethal genetic disorder of children. The mdx (C57BL/10 background, C57BL/10-mdx) mouse is a widely used model of DMD, but the histopathological hallmarks of DMD, such as the smaller number of myofibers, accumulation of fat and fibrosis, and insufficient regeneration of myofibers, are not observed in adult C57BL/10-mdx except for in the diaphragm. In this study, we showed that DBA/2 mice exhibited decreased muscle weight, as well as lower myofiber numbers after repeated degeneration–regeneration cycles. Furthermore, the self-renewal efficiency of satellite cells of DBA/2 is lower than that of C57BL/6. Therefore, we produced a DBA/2-mdx strain by crossing DBA/2 and C57BL/10-mdx. The hind limb muscles of DBA/2-mdx mice exhibited lower muscle weight, fewer myofibers, and increased fat and fibrosis, in comparison with C57BL/10-mdx. Moreover, remarkable muscle weakness was observed in DBA/2-mdx. These results indicate that the DBA/2-mdx mouse is a more suitable model for DMD studies, and the efficient satellite cell self-renewal ability of C57BL/10-mdx might explain the difference in pathologies between humans and mice.

Fukada, So-ichiro; Morikawa, Daisuke; Yamamoto, Yukiko; Yoshida, Tokuyuki; Sumie, Noriaki; Yamaguchi, Masahiko; Ito, Takahito; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Tsujikawa, Kazutake; Yamamoto, Hiroshi

2010-01-01

105

Restriction and sequence alterations affect DNA uptake sequence-dependent transformation in Neisseria meningitidis.  

PubMed

Transformation is a complex process that involves several interactions from the binding and uptake of naked DNA to homologous recombination. Some actions affect transformation favourably whereas others act to limit it. Here, meticulous manipulation of a single type of transforming DNA allowed for quantifying the impact of three different mediators of meningococcal transformation: NlaIV restriction, homologous recombination and the DNA Uptake Sequence (DUS). In the wildtype, an inverse relationship between the transformation frequency and the number of NlaIV restriction sites in DNA was observed when the transforming DNA harboured a heterologous region for selection (ermC) but not when the transforming DNA was homologous with only a single nucleotide heterology. The influence of homologous sequence in transforming DNA was further studied using plasmids with a small interruption or larger deletions in the recombinogenic region and these alterations were found to impair transformation frequency. In contrast, a particularly potent positive driver of DNA uptake in Neisseria sp. are short DUS in the transforming DNA. However, the molecular mechanism(s) responsible for DUS specificity remains unknown. Increasing the number of DUS in the transforming DNA was here shown to exert a positive effect on transformation. Furthermore, an influence of variable placement of DUS relative to the homologous region in the donor DNA was documented for the first time. No effect of altering the orientation of DUS was observed. These observations suggest that DUS is important at an early stage in the recognition of DNA, but does not exclude the existence of more than one level of DUS specificity in the sequence of events that constitute transformation. New knowledge on the positive and negative drivers of transformation may in a larger perspective illuminate both the mechanisms and the evolutionary role(s) of one of the most conserved mechanisms in nature: homologous recombination. PMID:22768309

Ambur, Ole Herman; Frye, Stephan A; Nilsen, Mariann; Hovland, Eirik; Tønjum, Tone

2012-07-02

106

Restriction and Sequence Alterations Affect DNA Uptake Sequence-Dependent Transformation in Neisseria meningitidis  

PubMed Central

Transformation is a complex process that involves several interactions from the binding and uptake of naked DNA to homologous recombination. Some actions affect transformation favourably whereas others act to limit it. Here, meticulous manipulation of a single type of transforming DNA allowed for quantifying the impact of three different mediators of meningococcal transformation: NlaIV restriction, homologous recombination and the DNA Uptake Sequence (DUS). In the wildtype, an inverse relationship between the transformation frequency and the number of NlaIV restriction sites in DNA was observed when the transforming DNA harboured a heterologous region for selection (ermC) but not when the transforming DNA was homologous with only a single nucleotide heterology. The influence of homologous sequence in transforming DNA was further studied using plasmids with a small interruption or larger deletions in the recombinogenic region and these alterations were found to impair transformation frequency. In contrast, a particularly potent positive driver of DNA uptake in Neisseria sp. are short DUS in the transforming DNA. However, the molecular mechanism(s) responsible for DUS specificity remains unknown. Increasing the number of DUS in the transforming DNA was here shown to exert a positive effect on transformation. Furthermore, an influence of variable placement of DUS relative to the homologous region in the donor DNA was documented for the first time. No effect of altering the orientation of DUS was observed. These observations suggest that DUS is important at an early stage in the recognition of DNA, but does not exclude the existence of more than one level of DUS specificity in the sequence of events that constitute transformation. New knowledge on the positive and negative drivers of transformation may in a larger perspective illuminate both the mechanisms and the evolutionary role(s) of one of the most conserved mechanisms in nature: homologous recombination.

Ambur, Ole Herman; Frye, Stephan A.; Nilsen, Mariann; Hovland, Eirik; T?njum, Tone

2012-01-01

107

Altered visual experience and acute visual deprivation affect predatory targeting by infrared-imaging Boid snakes.  

PubMed

Boid and Crotaline snakes use both their eyes and infrared-imaging facial pit organs to target homeothermic prey. These snakes can target in complete darkness, but the eyes can also effectively direct predatory strikes. We investigated the behavioral correlates of boid snakes' simultaneous use of two imaging systems by testing whether congenital unilateral visual deprivation affects targeting performance. Normally sighted Burmese pythons exhibited average targeting angle of zero (on the midline axis of the head), but three unilaterally anophthalmic Burmese pythons targeted preferentially on the sighted side. A unilaterally anophthalmic amethystine python also targeted on the sighted side, and a unilaterally anophthalmic Brazilian rainbow boa tended to target on the sighted side, though its mean targeting angle was not significantly different from zero. When unilaterally anophthalmic Burmese pythons were temporarily blinded, mean strike angle changed to that of normally sighted snakes. These results show that while infrared-imaging snakes can shift between visual and infrared information under acute experimental conditions, loss of part of the visual field during development results in abnormal predatory targeting behavior. In contrast, normally sighted snakes subjected to temporary unilateral blinding do not target preferentially on the sighted side. Therefore, while loss of part of the visual field may be compensated for by infrared input in normal snakes, partial absence of visual input during development may alter central organization of visual information. Conversely, absence of half the visual field during development does not alter targeting performance based upon infrared input alone, suggesting that organization of the central infrared map does not depend upon normal organization of visual input. PMID:11701137

Grace, M S; Woodward, O M

2001-11-23

108

Copy Number Variation Affecting the Photoperiod-B1 and Vernalization-A1 Genes Is Associated with Altered Flowering Time in Wheat (Triticum aestivum)  

PubMed Central

The timing of flowering during the year is an important adaptive character affecting reproductive success in plants and is critical to crop yield. Flowering time has been extensively manipulated in crops such as wheat (Triticum aestivum L.) during domestication, and this enables them to grow productively in a wide range of environments. Several major genes controlling flowering time have been identified in wheat with mutant alleles having sequence changes such as insertions, deletions or point mutations. We investigated genetic variants in commercial varieties of wheat that regulate flowering by altering photoperiod response (Ppd-B1 alleles) or vernalization requirement (Vrn-A1 alleles) and for which no candidate mutation was found within the gene sequence. Genetic and genomic approaches showed that in both cases alleles conferring altered flowering time had an increased copy number of the gene and altered gene expression. Alleles with an increased copy number of Ppd-B1 confer an early flowering day neutral phenotype and have arisen independently at least twice. Plants with an increased copy number of Vrn-A1 have an increased requirement for vernalization so that longer periods of cold are required to potentiate flowering. The results suggest that copy number variation (CNV) plays a significant role in wheat adaptation.

Isaac, Peter; Laurie, David A.

2012-01-01

109

Molecular Characterization of Chinese Hamster Cells Mutants Affected in Adenosine Kinase and Showing Novel Genetic and Biochemical Characteristics  

PubMed Central

Background Two isoforms of the enzyme adenosine kinase (AdK), which differ at their N-terminal ends, are found in mammalian cells. However, there is no information available regarding the unique functional aspects or regulation of these isoforms. Results We show that the two AdK isoforms differ only in their first exons and the promoter regions; hence they arise via differential splicing of their first exons with the other exons common to both isoforms. The expression of these isoforms also varied greatly in different rat tissues and cell lines with some tissues expressing both isoforms and others expressing only one of the isoforms. To gain insights into cellular functions of these isoforms, mutants resistant to toxic adenosine analogs formycin A and tubercidin were selected from Chinese hamster (CH) cell lines expressing either one or both isoforms. The AdK activity in most of these mutants was reduced to <5% of wild-type cells and they also showed large differences in the expression of the two isoforms. Thus, the genetic alterations in these mutants likely affected both regulatory and structural regions of AdK. We have characterized the molecular alterations in a number of these mutants. One of these mutants lacking AdK activity was affected in the conserved NxxE motif thereby providing evidence that this motif involved in the binding of Mg2+ and phosphate ions is essential for AdK function. Another mutant, FomR-4, exhibiting increased resistance to only C-adenosine analogs and whose resistance was expressed dominantly in cell-hybrids contained a single mutation leading to Ser191Phe alteration in AdK. We demonstrate that this mutation in AdK is sufficient to confer the novel genetic and biochemical characteristics of this mutant. The unusual genetic and biochemical characteristics of the FomR-4 mutant suggest that AdK in this mutant might be complexed with the enzyme AMP-kinase. Several other AdK mutants were altered in surface residues that likely affect its binding to the adenosine analogs and its interaction with other cellular proteins. Conclusions These AdK mutants provide important insights as well as novel tools for understanding the cellular functions of the two isoforms and their regulation in mammalian cells.

2011-01-01

110

Heritable genetic alterations in a xeroderma pigmentosum group G/Cockayne syndrome pedigree.  

PubMed

A search for genetic alterations within the XPG gene has been conducted on skin and blood cells cultured from a newly characterized xeroderma pigmentosum (XP) patient (XP20BE). This patient is the ninth known case that falls into the extremely rare XP complementation group G. Four genetic markers within the XPG gene (including two polymorphisms) demonstrated the Mendelian distribution of this gene from the parents to the patient and to an unaffected sibling. The patient (XP20BE) inherited a G to T transversion from his father in exon 1 of the XPG gene that resulted in the conversion of a glutamic acid at codon 11 to a termination codon. The patient also inherited an XP-G allele from his mother that produces an unstable or poorly expressed message. The cause of the latter defect is still uncertain. In addition to these alterations, XP20BE cDNA contained an mRNA species with a large splicing defect that encompassed a deletion from exon 1 to exon 14. This splicing defect, however, appears to be a naturally occurring low-frequency event that results from abnormal splicing that occurs between certain conserved non-consensus splicing signals within the human XPG gene. PMID:9447232

Okinaka, R T; Perez-Castro, A V; Sena, A; Laubscher, K; Strniste, G F; Park, M S; Hernandez, R; MacInnes, M A; Kraemer, K H

1997-11-01

111

An optimized technology platform for the rapid multiplex molecular analysis of genetic alterations associated with leukemia  

PubMed Central

Molecular methods play a critical role in the accurate diagnosis of leukemia by complementing morphologic, cytochemical, immunophenotypic, and cytogenetic analyses. We developed a multiplex RT-PCR method combined with liquid bead array cytometry for the rapid detection of genetic alterations associated with leukemia. Fusion transcripts corresponding to the most common recurrent chromosomal translocations were reproducibly detected in as low as 0.1 to 10 ng of total RNA with an analytical sensitivity of 0.01 to 1%. Multi-day, -lot, -operator, and -instrument precision studies for a total of 678 independent measures in 46 runs showed a very high reproducibility with 100% agreement between replicates. Using multiplex panels for four to twenty independent targets, we demonstrate the flexibility of the method to co-detect rare splicing isoforms, discriminate between multiple variants generated by unique cytogenetic abnormalities, identify distinct chromosomal partners involved with 11q23 or 17q21 rearrangements, and assess cryptic abnormalities not detectable by standard cytogenetics such as t(12;21), del(1p32), or NPM1 mutations. Overall, three different internal control transcripts and 34 variants resulting from eighteen abnormal chromosomal sites were evaluated. These results underscore the value of the multiplex assay system as a sensitive and reliable technology platform for the characterization of relevant genetic alterations in leukemia.

Ye, Fei; Laosinchai-Wolf, Walairat; Labourier, Emmanuel

2012-01-01

112

Genetic and Biochemical Alterations in Non-Small Cell Lung Cancer  

PubMed Central

Despite significant advances in the detection and treatment of lung cancer, it causes the highest number of cancer-related mortality. Recent advances in the detection of genetic alterations in patient samples along with physiologically relevant animal models has yielded a new understanding of the molecular etiology of lung cancer. This has facilitated the development of potent and specific targeted therapies, based on the genetic and biochemical alterations present in the tumor, especially non-small-cell lung cancer (NSCLC). It is now clear that heterogeneous cell signaling pathways are disrupted to promote NSCLC, including mutations in critical growth regulatory proteins (K-Ras, EGFR, B-RAF, MEK-1, HER2, MET, EML-4-ALK, KIF5B-RET, and NKX2.1) and inactivation of growth inhibitory pathways (TP53, PTEN, p16, and LKB-1). How these pathways differ between smokers and non-smokers is also important for clinical treatment strategies and development of targeted therapies. This paper describes these molecular targets in NSCLC, and describes the biological significance of each mutation and their potential to act as a therapeutic target.

Johnson, Jackie L.; Pillai, Smitha; Chellappan, Srikumar P.

2012-01-01

113

Urbanization affects stream ecosystem function by altering hydrology, chemistry, and biotic richness.  

PubMed

Catchment urbanization can alter physical, chemical, and biological attributes of stream ecosystems. In particular, changes in land use may affect the dynamics of organic matter decomposition, a measure of ecosystem function. We examined leaf-litter decomposition in 18 tributaries of the St. Johns River, Florida, USA. Land use in all 18 catchments ranged from 0% to 93% urban which translated to 0% to 66% total impervious area (TIA). Using a litter-bag technique, we measured mass loss, fungal biomass, and macroinvertebrate biomass for two leaf species (red maple [Acer rubrum] and sweetgum [Liquidambar styraciflua]). Rates of litter mass loss, which ranged from 0.01 to 0.05 per day for red maple and 0.006 to 0.018 per day for sweetgum, increased with impervious catchment area to levels of approximately 30-40% TIA and then decreased as impervious catchment area exceeded 40% TIA. Fungal biomass was also highest in streams draining catchments with intermediate levels of TIA. Macroinvertebrate biomass ranged from 17 to 354 mg/bag for red maple and from 15 to 399 mg/bag for sweetgum. Snail biomass and snail and total invertebrate richness were strongly related to breakdown rates among streams regardless of leaf species. Land-use and physical, chemical, and biological variables were highly intercorrelated. Principal-components analysis was therefore used to reduce the variables into several orthogonal axes. Using stepwise regression, we found that flow regime, snail biomass, snail and total invertebrate richness, and metal and nutrient content (which varied in a nonlinear manner with impervious surface area) were likely factors affecting litter breakdown rates in these streams. PMID:17069372

Chadwick, Michael A; Dobberfuhl, Dean R; Benke, Arthur C; Huryn, Alexander D; Suberkropp, Keller; Thiele, John E

2006-10-01

114

Altered structural connectivity in neonates at genetic risk for schizophrenia: a combined study using morphological and white matter networks.  

PubMed

Recently, an increasing body of evidence suggests that developmental abnormalities related to schizophrenia may occur as early as the neonatal stage. Impairments of brain gray matter and wiring problems of axonal fibers are commonly suspected to be responsible for the disconnection hypothesis in schizophrenia adults, but significantly less is known in neonates. In this study, we investigated 26 neonates who were at genetic risk for schizophrenia and 26 demographically matched healthy neonates using both morphological and white matter networks to examine possible brain connectivity abnormalities. The results showed that both populations exhibited small-world network topology. Morphological network analysis indicated that the brain structural associations of the high-risk neonates tended to have globally lower efficiency, longer connection distance, and less number of hub nodes and edges with relatively higher betweenness. Subgroup analysis showed that male neonates were significantly disease-affected, while the female neonates were not. White matter network analysis, however, showed that the fiber networks were globally unaffected, although several subcortical-cortical connections had significantly less number of fibers in high-risk neonates. This study provides new lines of evidence in support of the disconnection hypothesis, reinforcing the notion that the genetic risk of schizophrenia induces alterations in both gray matter structural associations and white matter connectivity. PMID:22613620

Shi, Feng; Yap, Pew-Thian; Gao, Wei; Lin, Weili; Gilmore, John H; Shen, Dinggang

2012-05-19

115

Prospects for "genetic therapy" -- can a person benefit from being altered?  

PubMed

Mapping the human genome is an immense project with numerous objectives. Indeed, it is likely that some of its most important ramifications and applications remain as yet unglimpsed. All we can presently attempt is to focus on some of the more obvious possibilities and prepare for the problems already looming on our horizon. One such possibility is that of Prenatal Genetic Intervention (PGI), which might be said to be a therapeutic intervention on behalf of the embryonic child. In this paper, I argue that "genetic therapy" is likely to be a misnomer, and that if PGI becomes possible, we should generally resist its inclusion under the special moral duty of providing health care. "Therapy" necessarily means helping a person, while PGI -- though effecting improvements from an impersonal perspective -- will frequently not consist in directly helping any person. This is due not to the embryo not being a person, but rather to the basic philosophical problem of personal identity persisting through significant alterations -- especially the alteration of genotype. The decisive moral question then hinges on the definition of "significant" alteration. I shall examine the feasibility of drawing analogies from criteria for personal identity proposed in discussions of how persons maintain their identity across time and through physical and psychological change. Certain metaphysical aspects of human identity and individuality will be also touched upon, partly in terms derived from classical Judaism. In conclusion I argue that, regarding embryos in particular, persistence of genotype must generally be deemed a necessary condition for maintaining personal identity. Therefore, many proposals for PGI should be excluded from the notion of therapeutic intervention and thus denied the special moral status of requests for therapy. PMID:11653948

Zohar, Noam J

1991-10-01

116

Genetic deletion of monoacylglycerol lipase alters endocannabinoid-mediated retrograde synaptic depression in the cerebellum  

PubMed Central

Abstract The endocannabinoid (eCB) 2-arachidonoylglycerol (2-AG) is hydrolysed primarily by monoacylglycerol lipase (MAGL). Here, we investigated whether eCB-mediated retrograde synaptic depression in cerebellar slices was altered in MAGL knockout (MAGL?/?) mice. Depolarization-induced suppression of excitation (DSE) and metabotropic glutamate receptor (mGluR1)-mediated synaptic depression are mediated by 2-AG-induced activation of CB1 receptors. We show that genetic deletion of MAGL prolonged DSE at parallel fibre (PF) or climbing fibre (CF) to Purkinje cell (PC) synapses. Likewise, mGluR1-mediated synaptic depression, induced either by high-frequency stimulation of PF or mGluR1 agonist DHPG, was prolonged in MAGL?/? mice. About 15% of 2-AG in the brain is hydrolysed by serine hydrolase ?-?-hydrolase domain 6 and 12 (ABHD6 and ABHD12). However, the selective ABHD6 inhibitor WWL123 had no significant effect on cerebellar DSE in MAGL+/+ and ?/? mice. The CB1 receptor antagonist SR141716 significantly increased the amplitude of basal excitatory postsynaptic currents (EPSCs) in MAGL?/? mice but not in MAGL+/+ mice. Conversely, the CB1 agonist WIN55212 induced less depression of basal EPSCs in MAGL?/? mice than in MAGL+/+ mice. These results provide genetic evidence that inactivation of 2-AG by MAGL determines the time course of eCB-mediated retrograde synaptic depression and that genetic deletion of MAGL causes tonic activation and consequential desensitization of CB1 receptors.

Zhong, Peng; Pan, Bin; Gao, Xiu-ping; Blankman, Jacqueline L; Cravatt, Benjamin F; Liu, Qing-song

2011-01-01

117

Genetic compatibility affects division of labor in the Argentine ant Linepithema humile.  

PubMed

Division of labor is central to the organization of insect societies. Within-colony comparisons between subfamilies of workers (patrilines or matrilines) revealed genetic effects on division of labor in many social insect species. Although this has been taken as evidence for additive genetic effects on division of labor, it has never been experimentally tested. To determine the relative roles of additive and nonadditive genetic effects (e.g., genetic compatibility, epistasis, and parent-of-origin imprinting effects) on worker behavior, we performed controlled crosses using the Argentine ant Linepithema humile. Three of the measured behaviors (the efficiency to collect pupae, the foraging propensity, and the distance between non-brood-tenders and brood) were affected by the maternal genetic background and the two others (the efficiency to feed larvae and the distance between brood-tenders and brood) by the paternal genetic background. Moreover, there were significant interactions between the maternal and paternal genetic backgrounds for three of the five behaviors. These results are most consistent with parent-of-origin and genetic compatibility effects on division of labor. The finding of nonadditive genetic effects is in strong contrast with the current view and has important consequences for our understanding of division of labor in insect societies. PMID:23356622

Libbrecht, Romain; Keller, Laurent

2012-09-24

118

Genetics of early onset bipolar affective disorder: Are we making progress?  

Microsoft Academic Search

Though considerable progress has been made in understanding the molecular genetics of bipolar affective dis order, few studies\\u000a are currently focusing on the genetics of prepubertal or early adolescent onset illness. A variety of studies of the phenomenology,\\u000a imaging and comorbidity of early onset bipolarity find significant differences from late onset illness. These studies raise\\u000a the notion that early onset

Richard D. Todd

2002-01-01

119

Omega-3 fatty acids deprivation affects ontogeny of glutamatergic synapses in rats: relevance for behavior alterations.  

PubMed

Essential omega-3 polyunsaturated fatty acids (omega3) are crucial to brain development and function, being relevant for behavioral performance. In the present study we examined the influence of dietary omega3 in the development of the glutamatergic system and on behavior parameters in rats. Female rats received isocaloric diets, either with omega3 (omega3 group) or a omega3 deficient diet (D group). In ontogeny experiments of their litters, hippocampal immunocontent of ionotropic NMDA and AMPA glutamatergic receptors subunits (NR2 A\\B and GluR1, respectively) and the alpha isoform of the calcium-calmodulin protein kinase type II (alphaCaMKII) were evaluated. Additionally, hippocampal [(3)H]glutamate binding and uptake were assessed. Behavioral performance was evaluated when the litters were adult (60 days old), through the open-field, plus-maze, inhibitory avoidance and flinch-jump tasks. The D group showed decreased immunocontent of all proteins analyzed at 02 days of life (P2) in comparison with the omega3 group, although the difference disappeared at 21 days of life (except for alphaCaMKII, which content normalized at 60 days old). The same pattern was found for [(3)H]glutamate binding, whereas [(3)H]glutamate uptake was not affected. The D group also showed memory deficits in the inhibitory avoidance, increased in the exploratory pattern in open-field, and anxiety-like behavior in plus-maze. Taken together, our results suggest that dietary omega3 content is relevant for glutamatergic system development and for behavioral performance in adulthood. The putative correlation among the neurochemical and behavioral alterations caused by dietary omega3 deficiency is discussed. PMID:20172010

Moreira, Júlia D; Knorr, Luisa; Ganzella, Marcelo; Thomazi, Ana Paula; de Souza, Carolina G; de Souza, Débora G; Pitta, Carolina F; Mello e Souza, Tadeu; Wofchuk, Susana; Elisabetsky, Elaine; Vinadé, Lúcia; Perry, Marcos L S; Souza, Diogo O

2010-02-19

120

Collecting Duct Carcinomas Represent a Unique Tumor Entity Based on Genetic Alterations  

PubMed Central

Collecting duct carcinoma (CDC) is a rare renal neoplasm that is associated with poor prognosis due to its highly aggressive course and limited response to immuno- or chemotherapy. Histologically, CDC is defined as a subtype of renal cell carcinomas, but in some cases, it is difficult to differentiate from urothelial carcinomas (UC). Therefore the aim of this study was to determine genetic alterations of CDC in comparison to that of urothelial carcinomas of the upper urinary tract (UUT-UC) to clarify the histological origin of this rare tumor entity. Twenty-nine CDC samples were obtained from seven different German centers and compared with twenty-six urothelial carcinomas of the upper urinary tract. Comparative genomic hybridization (CGH) was used to investigate the genetic composition of patients’ tumors and allowed the detection of losses and gains of DNA copy numbers throughout the entire genome. The clinical data were correlated with CGH results. CGH analysis of CDC revealed DNA aberrations in many chromosomes. DNA losses were more frequently observed than gains, while high-level amplifications were not detected. The mean frequency of CDC chromosomal aberrations (4.9/case) was slightly lower than that in UUT-UC (5.4/case). Recurrent CDC DNA losses occurred at 8p (n=9/29), 16p (9/29), 1p (n=7/29) and 9p (n=7/29), and gains occurred in 13q (n=9/29). In contrast to CDC, the most frequently detected UUT-UC DNA aberration was a loss at 9q (n=13/26). DNA losses at 9q, 13q and 8q as well as gains at 8p showed significant variations in UUT-UC compared to CDC. There was no correlation between the patients’ clinical course and the presence or absence of these recurrent genetic alterations. CDCs are characterized by a different genetic pattern compared to UUT-UC. Regarding the published data on renal cell carcinoma, we conclude that CDC appears to be a unique entity among kidney carcinomas.

Parr, Martin; Hartmann, Arndt; Fussel, Susanne; Toma, Marieta; Grobholz, Rainer; Pflugmann, Thomas; Wullich, Bernd; Strauss, Arne; Behnes, Carl Ludwig; Otto, Wolfgang; Stockle, Michael; Jung, Volker

2013-01-01

121

Micronucleus test and observation of nuclear alterations in erythrocytes of Nile tilapia exposed to waters affected by refinery effluent  

Microsoft Academic Search

Micronuclei and nuclear alterations tests were performed on erythrocytes of Oreochromis niloticus (Perciformes, Cichlidae) in order to evaluate the water quality from Paraíba do Sul river, in an area affected by effluents from an oil shale processing plant, located in the city of São José dos Campos, Brazil-SP. Water samples were collected on 2004 May and August (dry season) and

Tatiana da Silva Souza; Carmem S. Fontanetti

2006-01-01

122

Drug-induced and Genetic Alterations in Stress-Responsive Systems: Implications for Specific Addictive Diseases  

PubMed Central

From the earliest work in our laboratory, we hypothesized, and with studies conducted in both clinical research and animal models, we have shown that drugs of abuse, administered or self-administered, on a chronic basis, profoundly alter stress-responsive systems. Alterations of expression of specific genes involved in stress responsivity, with increases or decreases in mRNA levels, receptor and neuropeptide levels, and resultant changes in hormone levels, have been documented to occur after chronic intermittent exposure to heroin, morphine, other opiates, cocaine, other stimulants and alcohol in animal models and in human molecular genetics. The best studied of the stress-responsive systems in humans and mammalian species in general is undoubtedly the HPA axis. In addition, there are stress-responsive systems in other parts in the brain itself, and some of these include components of the HPA axis, such as CRF and CRF receptors, along with POMC gene and gene products. Several other stress-responsive systems are known to influence the HPA axis, such as the vasopressin-vasopressin receptor system. Orexin-hypocretin, acting at its receptors, may effect changes which suggest that it should be properly categorized as a stress-responsive system. However, less is known about the interactions and connectivity of some of these different neuropeptide and receptor systems, and in particular, about the possible connectivity of fast-acting (e.g., glutamate and GABA) and slow-acting (including dopamine, serotonin and norepinephrine) neurotransmitters with each of these stress-responsive components and the resultant impact, especially in the setting of chronic exposure to drugs of abuse. Several of these stress-responsive systems and components, primarily based on our laboratory-based and human molecular genetics research of addictive diseases, will be briefly discussed in this review.

Zhou, Yan; Proudnikov, Dmitri; Yuferov, Vadim; Kreek, Mary Jeanne

2009-01-01

123

Primary tumour genetic alterations and intra-tumoral heterogeneity are maintained in xenografts of human colon cancers showing chromosome instability.  

PubMed

Evaluation of the role of clonal heterogeneity in colon tumour sensitivity/resistance to drugs and/or in conferring metastatic potential requires an adequate experimental model in which the tumour cells maintain the initial genetic alterations and intra-tumoral heterogeneity through maintenance of the genetic clones present in the initial tumour. Therefore, we xenografted subcutaneously into nude mice seven human colonic tumours (from stages B1 to D) that showed chromosome instability and transplanted them sequentially for up to 14 passages. Maintenance after xenografting of the genetic alterations present in the initial tumours was scored by allelotype studies targeting 45 loci localized on 18 chromosomes. We show that xenografting does not alter the genetic or the histological profiles of the tumours even after 14 passages. Screening of the entire genome of one tumour by comparative genome hybridization also showed overall stability of the alterations between the initial and the xenografted tumour. In addition, intra-tumoral heterogeneity was maintained over time, suggesting that no clonal selection occurred in the nude mice. The observation that some loci showed partial allelic imbalance in the initial tumour but loss of heterozygosity after the first passage in nude mice when all the normal cells were lost may allow identification of interesting genetic defects that could be involved in tumour expansion. Thus, sequential xenografts of colon tumours will provide a powerful model for further study of tumour clonality and for the identification of genetic profiles responsible for differential resistance to therapeutic treatments. Our data also suggest that tumour expansion can result from alterations in several distinct genetic pathways. PMID:16450341

Guenot, D; Guérin, E; Aguillon-Romain, S; Pencreach, E; Schneider, A; Neuville, A; Chenard, M-P; Duluc, I; Du Manoir, S; Brigand, C; Oudet, P; Kedinger, M; Gaub, M-P

2006-04-01

124

ICLAS Working Group on Harmonization: international guidance concerning the production care and use of genetically-altered animals.  

PubMed

Replacement, Reduction and Refinement, the ‘Three Rs’ of Russell & Burch, are accepted worldwide as fundamental to the ethics of animal experimentation. The production, care and use of genetically-altered animals can pose particular challenges to the implementation of the Three Rs,1 necessitating additional considerations by those responsible for overseeing the ethical use and appropriate care of animals involved in science. The International Council for Laboratory Animal Science brings representatives of the international laboratory animal science community together to recommend acceptance of guidance documents.The harmonization of guidance concerning genetically-altered animals was seen as a priority because of the increasing globalization of research involving these animals. PMID:23563121

Rose, M; Everitt, J; Hedrich, H; Schofield, J; Dennis, M; Scott, E; Griffin, G

2013-07-01

125

Genetic alterations in RAS-regulated pathway in acral lentiginous melanoma.  

PubMed

Studies integrating clinicopathological and genetic features have revealed distinct patterns of genomic aberrations in Melanoma. Distributions of BRAF or NRAS mutations and gains of several oncogenes differ among melanoma subgroups, while 9p21 deletions are found in all melanoma subtypes. In the study, status of genes involved in cell cycle progression and apoptosis was evaluated in a panel of 17 frozen primary acral melanomas. NRAS mutations were found in 17% of the tumors. In contrast, BRAF mutations were not found. Gains of AURKA gene (20q13.3) were detected in 37.5% of samples, gains of CCND1 gene (11q13) or TERT gene (5p15.33) in 31.2% and gains of NRAS gene (1p13.2) in 25%. Alterations in 9p21 were identified in 69% of tumors. Gains of 11q13 and 20q13 were mutually exclusive, and 1p13.2 gain was associated with 5p15.33. Our findings showed that alterations in RAS-related pathways are present in 87.5% of acral lentiginous melanomas. PMID:23362874

Puig-Butillé, Joan A; Badenas, Celia; Ogbah, Zighereda; Carrera, Cristina; Aguilera, Paula; Malvehy, Josep; Puig, Susana

2013-02-01

126

Psychosocial and cultural factors affecting the perceived riskof genetically modified food: an overview of the literature  

Microsoft Academic Search

The rapid globalization of the world economy has increased the need for an astute understanding of cultural differences in perceptions, values, and ways of thinking about new food technologies. In this paper, we describe how socio-psychological and cultural factors may affect public perceptions of the riskof genetically modified (GM) food. We present psychological, sociological, and anthropological research on riskperception as

Melissa L. Finucane; Joan L. Holup

127

Delineation of Behavioral Phenotypes in Genetic Syndromes: Characteristics of Autism Spectrum Disorder, Affect and Hyperactivity  

ERIC Educational Resources Information Center

We investigated autism spectrum disorder (ASD) symptomatology, hyperactivity and affect in seven genetic syndromes; Angelman (AS; n = 104), Cri du Chat (CdCS; 58), Cornelia de Lange (CdLS; 101), Fragile X (FXS; 191), Prader-Willi (PWS; 189), Smith-Magenis (SMS; 42) and Lowe (LS; 56) syndromes (age range 4-51). ASD symptomatology was heightened in…

Oliver, Chris; Berg, Katy; Moss, Jo; Arron, Kate; Burbidge, Cheryl

2011-01-01

128

Affective Influences on Risk Perceptions of, and Attitudes Toward, Genetically Modified Food  

Microsoft Academic Search

Much has been written about risk perceptions and public understanding of genetically modified (GM) food, yet little if any of the academic writings on this topic take into account the role of feelings or affect in these processes. Here, the available literature on the topic of GM food is explored in order to highlight findings consistent with the notion that

Ellen Townsend

2006-01-01

129

Genetic linkage analysis of bipolar affective disorder in an Old Order Amish pedigree  

Microsoft Academic Search

We have used genetic linkage analysis in an effort to identify a gene responsible for bipolar affective disorder (BAD) in an Old Order Amish pedigree. The initial study of this pedigree showed strong evidence for linkage of the chromosome 11p15 markers HRAS1 and the insulin gene (INS) to BAD, whereas a second report found no evidence for linkage. We have

Adam Law; Charles W. Richard; Robert W. Cottingham; G. Mark Lathrop; David R. Cox; Richard M. Myers

1992-01-01

130

Genetic alterations of Carney complex are not present in sporadic cardiac myxomas.  

PubMed

Cardiac myxomas are the most frequent cardiac tumors and cause for significant morbidity and mortality. Recent evidence indicates that cardiac myxomas are, in fact, neoplasms rather than organized thrombi. Cardiac myxomas may present as solitary lesions or in association with the Carney complex. Carney complex has been linked to chromosome 2p16 and the PRKAR1A gene at 17q22-24. In this study, we analyzed sporadic cardiac myxomas to evaluate whether the genetic alterations seen in Carney complex are present in non Carney complex associated cardiac myxomas as well. We analyzed microdissected material from 13 patients with cardiac myxomas for the markers PRKAR1 9CA, D2S2153, D2S2251 and D2S123. None of the cases demonstrated loss of heterozygosity or definite band changes suggestive of microsatellite instability for any of the markers used. We conclude that sporadic cardiac myxomas are genetically not related to Carney complex and most likely do not represent an incomplete form of Carney complex. PMID:11744997

Fogt, Franz; Zimmerman, Robert L; Hartmann, Christopher J; Brown, Charlotte A; Narula, Navneet

2002-01-01

131

Cytarabine induced cerebellar neuronal damage in juvenile rat: correlating neurobehavioral performance with cellular and genetic alterations.  

PubMed

Cytosine arabinoside (Ara-C), a pyrimidine analogue induces cerebellar dysfunction and behavioral abnormalities. Although many in vitro experiments have been conducted in the past demonstrating the lethal potential of Ara-C to cerebellar neurons, there is a paucity of literature available regarding the effects of Ara-C on the cellular and genetic material of cerebellum and its subsequent influence on the neurobehavioral performance in vivo. Rats were treated with Ara-C at the dose levels 50, 100 and 200mg/kg/day for 5 and 14 days by intraperitoneal (i.p.) route. Endpoints of the evaluation included food and water intake, body and organ weight, behavioral parameters, histopathology, oxidative stress, DNA damage, apoptosis, expression of p53, caspase-3 and calbindin D-28K (calbindin) as well as histone acetylation and methylation. Ara-C treatment for 14 days significantly decreased the food and water intake, body weight gain and brain weight in rat as compared to the control. Alterations in various behavioral parameters were observed, indicating the impaired cerebellar function. Further, cellular abnormalities in the cerebellum such as Purkinje cell misalignment and granule cell cytotoxicity were observed. Positive correlation was observed between Ara-C induced disturbance in the motor performance and the Purkinje cell loss in rat cerebellum. Moreover, Ara-C treatment significantly increased the oxidative stress, DNA damage, TUNEL positive cells, p53 and caspase-3 positive cells in the rat cerebellum. Unlike short-term treatment, long-term Ara-C treatment significantly reduced calbindin expression in the cerebellum. Apart from this, 14 days Ara-C treatment led to significant alterations in the histone acetylation and methylation in the cerebellum, while in 5 days treatment no such alterations were observed. Present results indicated that Ara-C, by inducing oxidative stress mediated DNA damage, executes neuronal apoptosis which is accompanied by an increase in the p53 and caspase-3, but decrease in the calbindin expression. PMID:22212197

Patel, Ronak S; Rachamalla, Mahesh; Chary, Namoju R; Shera, Firdos Y; Tikoo, Kulbhushan; Jena, Gopabandhu

2011-12-24

132

Epigenetic and genetic alterations of the imprinting disorder Beckwith-Wiedemann syndrome and related disorders.  

PubMed

Genomic imprinting is an epigenetic phenomenon that leads to parent-specific differential expression of a subset of genes. Most imprinted genes form clusters, or imprinting domains, and are regulated by imprinting control regions. As imprinted genes have an important role in growth and development, aberrant expression of imprinted genes due to genetic or epigenetic abnormalities is involved in the pathogenesis of human disorders, or imprinting disorders. Beckwith-Wiedemann syndrome (BWS) is a representative imprinting disorder characterized by macrosomia, macroglossia and abdominal wall defects, and exhibits a predisposition to tumorigenesis. The relevant imprinted chromosomal region in BWS is 11p15.5, which consists of two imprinting domains, IGF2/H19 and CDKN1C/KCNQ1OT1. BWS has five known causative epigenetic and genetic alterations: loss of methylation (LOM) at KvDMR1, gain of methylation (GOM) at H19DMR, paternal uniparental disomy, CDKN1C mutations and chromosomal rearrangements. Opposite methylation defects, GOM and LOM, at H19DMR are known to cause clinically opposite disorders: BWS and Silver-Russell syndrome, respectively. Interestingly, a recent study discovered that loss of function or gain of function of CDKN1C also causes clinically opposite disorders, BWS and IMAGe (intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita, and genital anomalies) syndrome, respectively. Furthermore, several clinical studies have suggested a relationship between assisted reproductive technology (ART) and the risk of imprinting disorders, along with the existence of trans-acting factors that regulate multiple imprinted differentially methylated regions. In this review, we describe the latest knowledge surrounding the imprinting mechanism of 11p15.5, in addition to epigenetic and genetic etiologies of BWS, associated childhood tumors, the effects of ART and multilocus hypomethylation disorders. PMID:23719190

Soejima, Hidenobu; Higashimoto, Ken

2013-05-30

133

Parents' communication with siblings of children affected by an inherited genetic condition.  

PubMed

The objective of this study was to explore parents' communication about risk with siblings of children affected by an inherited genetic condition, and to ascertain what level of support, if any, is required from health professionals. Semi-structured interviews were conducted with affected and unaffected children and their parents. Families were affected by one of six genetic conditions representing different patterns of inheritance and variations in age of onset, life expectancy and impact on families. Interviews were analysed using constructivist grounded theory and informed by models which focused on three different aspects of family communication. Interviews with 33 families showed that siblings' information and support needs go largely unrecognized by health professionals and sometimes by parents. Some siblings were actively informed about the genetic condition by parents, others were left to find out and assimilate information by themselves. Siblings were given information about the current symptoms and management of the genetic condition but were less likely to know about its hereditary nature and their own potential risk. When siblings were fully informed about the condition and included in family discussion, they had a better understanding of their role within their family, and family relationships were reported to be more harmonious. The information and support needs of siblings can be overlooked. Parents with the responsibility for caring for a child affected by a genetic condition may require support from health professionals to understand and respond to their unaffected children's need for more information about the genetic condition and its implications for the children's own future health and reproductive decision-making. PMID:21503823

Plumridge, Gillian; Metcalfe, Alison; Coad, Jane; Gill, Paramjit

2011-04-19

134

Genetic and Epigenetic Alterations in Primary-Progressive Paired Oligodendroglial Tumors  

PubMed Central

The aim of the present study was to identify genetic and epigenetic alterations involved in the progression of oligodendroglial tumors. We characterized 21 paired, World Health Organization (WHO) grade II and III oligodendroglial tumors from patients who received craniotomies for the partial or complete resection of primary and secondary oligodendroglial tumors. Tumor DNA was analyzed for alterations in selected genetic loci (1p36, 9p22, 10q23–24, 17p13, 19q13, 22q12), isocitrate dehydrogenase 1 (IDH1), isocitrate dehydrogenase 2 (IDH2) and the CpG island methylation status of critical tumor-related genes (MGMT, P16, DAPK, PTEN, RASSF1A, Rb1). Alterations of these markers were common early in the tumorigenesis. In the primary tumors we identified 12 patients (57.1%) with 1p36 deletions, 17 (81.0%) with 19q13 deletions, 9 (42.9%) with 1p36/19q13 codeletions, 11 (52.3%) with 9p22 deletions, and 12 (57.1%) with IDH1 mutation. Epigenetic analysis detected promoter methylation of the MGMT, P16, DAPK, PTEN, RASSF1A, and Rb1 genes in 38.1%, 19.0%, 38.1%, 33.3%, 66.7%, and 14.3% of primary tumors, respectively. After progression, additional losses of 1p, 9p, 10q, 17p, 19q and 22q were observed in 3 (14.3%), 1 (4.8%), 3 (14.3%), 2 (9.5%), 1 (4.8%) and 3 (14.3%) cases, respectively. Additional methylations of the MGMT, P16, DAPK, PTEN, RASSF1A, and RB1 promoters was observed in 4 (19.0%), 2 (9.5%), 0 (0%), 6 (28.6%), 2(9.5%) and 3 (14.3%) cases, respectively. The status of IDH1 mutation remained unchanged in all tumors after progression. The primary tumors of three patients with subsequent progression to high-grade astrocytomas, all had 9p deletion, intact 1p, intact 10q and unmethylated MGMT. Whether this may represent a molecular signature of patients at-risk for the development of aggressive astrocytomas needs further investigation.

Kuo, Lu-Ting; Tsai, Shao-Yu; Chang, Cheng-Chi; Kuo, Kuang-Ting; Huang, Abel Po-Hao; Tsai, Jui-Chang; Tseng, Ham-Min; Kuo, Meng-Fai; Tu, Yong-Kwang

2013-01-01

135

Genetic and epigenetic alterations in primary-progressive paired oligodendroglial tumors.  

PubMed

The aim of the present study was to identify genetic and epigenetic alterations involved in the progression of oligodendroglial tumors. We characterized 21 paired, World Health Organization (WHO) grade II and III oligodendroglial tumors from patients who received craniotomies for the partial or complete resection of primary and secondary oligodendroglial tumors. Tumor DNA was analyzed for alterations in selected genetic loci (1p36, 9p22, 10q23-24, 17p13, 19q13, 22q12), isocitrate dehydrogenase 1 (IDH1), isocitrate dehydrogenase 2 (IDH2) and the CpG island methylation status of critical tumor-related genes (MGMT, P16, DAPK, PTEN, RASSF1A, Rb1). Alterations of these markers were common early in the tumorigenesis. In the primary tumors we identified 12 patients (57.1%) with 1p36 deletions, 17 (81.0%) with 19q13 deletions, 9 (42.9%) with 1p36/19q13 codeletions, 11 (52.3%) with 9p22 deletions, and 12 (57.1%) with IDH1 mutation. Epigenetic analysis detected promoter methylation of the MGMT, P16, DAPK, PTEN, RASSF1A, and Rb1 genes in 38.1%, 19.0%, 38.1%, 33.3%, 66.7%, and 14.3% of primary tumors, respectively. After progression, additional losses of 1p, 9p, 10q, 17p, 19q and 22q were observed in 3 (14.3%), 1 (4.8%), 3 (14.3%), 2 (9.5%), 1 (4.8%) and 3 (14.3%) cases, respectively. Additional methylations of the MGMT, P16, DAPK, PTEN, RASSF1A, and RB1 promoters was observed in 4 (19.0%), 2 (9.5%), 0 (0%), 6 (28.6%), 2(9.5%) and 3 (14.3%) cases, respectively. The status of IDH1 mutation remained unchanged in all tumors after progression. The primary tumors of three patients with subsequent progression to high-grade astrocytomas, all had 9p deletion, intact 1p, intact 10q and unmethylated MGMT. Whether this may represent a molecular signature of patients at-risk for the development of aggressive astrocytomas needs further investigation. PMID:23826216

Kuo, Lu-Ting; Tsai, Shao-Yu; Chang, Cheng-Chi; Kuo, Kuang-Ting; Huang, Abel Po-Hao; Tsai, Jui-Chang; Tseng, Ham-Min; Kuo, Meng-Fai; Tu, Yong-Kwang

2013-06-24

136

Altered Groundwater Inflow Affects Biogeochemical Patterns in Iron Rich and Acidic Sediments  

NASA Astrophysics Data System (ADS)

Sediments of acidic mining lakes are characterized by steep geochemical gradients. Typically, anoxic and moderately acidic (pH 5) groundwater high in ferrous iron and sulfate passes the sediment (10-20 cm) and the pH drops to values as low as 2.8 in the lake water. In the sediment, bacterial iron reduction predominates; sulfate reduction is viable only at a pH of >5. The uppermost sediment is oxic, ferrous iron is oxidized and precipitates. We tested the hypothesis, that the inflow of moderately acidic (pH 5), anoxic groundwater increases the retention of ferrous iron as sulfide or carbonate in the sediment of an acidic mining lake by altering pore water chemistry and elevating the sediment pH. In a laboratory column experiment, lake sediment was percolated with groundwater of different iron and sulfate concentrations (15 and 10 mmol/l vs. 1 and 1 mmol/l) and flow rates (0, 5 and 20 mm/d). Effects on sediment and pore water chemistry were estimated by sampling the percolate, solid phase and pore water. The effect of different treatments in the first 6 weeks of incubation at 10 °C was low. The outflow remained low in pH and acidity production predominated (4.7-31.4 mol m-2~a-1). High Fe and sulfate concentrations in the outflow indicated reductive dissolution of iron hydroxosulfate minerals. The addition of DOC (25 mg/l) to the percolate and a temperature of 20 °C initiated sulfate reduction (0.3-6.6 mol H+ eq. m-2~a-1) after 60-80 days and increased the pH in the outflow of columns with fast flow rates (20 mm/d) to ~5. Higher pH accelerated schwertmannite transformation into goethite by a factor of >2 but also iron release from the sediment, especially in treatments receiving low concentrations of iron and sulfate. In those treatments the induced groundwater flow remobilised substantial quantities of iron (1.2-20.5 mol m-2~a-1) and sulfate (8.7-20 mol m-2~a-1), making up >50 % of the total load in the outflow. Contrarily, in the treatments receiving dump impacted groundwater, a remarkable amount of ferrous iron was retained (up to 40.5 mol m-2~a-1). The study demonstrates that changes in groundwater inflow will affect geochemical gradients and biogeochemical processes in iron rich and acidic sediments.

Knorr, K.; Blodau, C.

2005-12-01

137

Alterations in transport path differentially affect temporal and spatial movement parameters  

Microsoft Academic Search

Many studies have examined the coordination of reach-to-grasp movements. However, there is debate regarding the mechanism\\u000a of coordination between the transport and grasp components. The current study investigated the stability of temporal and spatial\\u000a measures for reaches in which transport path was altered early or late in the reaching action. Transport alteration was accomplished\\u000a by placing an obstacle either 10 cm

Jay L. Alberts; Marian Saling; George E. Stelmach

2002-01-01

138

Use of Closely Related Affected Individuals for the Genetic Study of Complex Diseases in Founder Populations  

PubMed Central

We propose a method, the maximum identity length contrast (MILC) statistic, to locate genetic risk factors for complex diseases in founder populations. The MILC approach compares the identity length of parental haplotypes that are transmitted to affected offspring with the identity length of those that are not transmitted to affected offspring. Initially, the statistical properties of the method were assessed using randomly selected affected individuals with unknown relationship. Because both nuclear families with multiple affected sibs and large pedigrees are often available in founder populations, we performed simulations to investigate the properties of the MILC statistic in the presence of closely related affected individuals. The simulation showed that the use of closely related affected individuals greatly enhances the power of the statistic. For a given sample size and type I error, the use of affected sib pairs, instead of affected individuals randomly selected from the population, could increase the power by a factor of two. This increase was related to an increase of kinship-coefficient contrast between haplotype groups when closely related individuals were considered. The MILC approach allows the simultaneous use of affected individuals from a founder population and affected individuals with any kind of relationship, close or remote. We used the MILC approach to analyze the role of HLA in celiac disease and showed that the effect of HLA may be detected with the MILC approach by typing only 11 affected individuals, who were part of a single large Finnish pedigree.

Bourgain, C.; Genin, E.; Holopainen, P.; Mustalahti, K.; Maki, M.; Partanen, J.; Clerget-Darpoux, F.

2001-01-01

139

[Effects of indol-3-carbinol and epigallocatexin-3-gallate on alteration and reparation in affected urethra of experimental animals].  

PubMed

The effects of indol-3-carbinol and epigallocatexin-3-gallate on alteration and reparation in the urethra were studied in 30 male Shinshilla rabbits. From the observation day 2 the rabbits were fed with indol-3-carbinol and epigallocatexin-3-gallate in addition to standard diet. Microcirculation was assessed with a laser analyzer of capillary circulation LAKK-01 which detected earlier recovery of microcirculation in the group of the animals fed with indol-3-carbinol and epigallocatexin-3-gallate. Thus, antioxidant and antiproliferative properties of indol-3-carbinol and epigallocatexin-3-gallate improve alteration and reparation in affected urethra due to development of soft elastic connective tissue with better capillary circulation. PMID:20209866

Pavlov, V N; Kazikhinurov, A A; Safiullin, R I; Kazikhinurov, R A; Kutushev, K G; Valiev, I R

140

Behavioral Studies and Genetic Alterations in Corticotropin-Releasing Hormone (CRH) Neurocircuitry: Insights into Human Psychiatric Disorders.  

PubMed

To maintain well-being, all organisms require the ability to re-establish homeostasis in the presence of adverse physiological or psychological experiences. The regulation of the hypothalamic-pituitary adrenal (HPA) axis during stress is important in preventing maladaptive responses that may increase susceptibility to affective disorders. Corticotropin-releasing hormone (CRH) is a central stress hormone in the HPA axis pathway and has been implicated in stress-induced psychiatric disorders, reproductive and cardiac function, as well as energy metabolism. In the context of psychiatric disorders, CRH dysfunction is associated with the occurrence of post-traumatic stress disorder, major depression, anorexia nervosa, and anxiety disorders. Here, we review the synthesis, molecular signaling and regulation, as well as synaptic activity of CRH. We go on to summarize studies of altered CRH signaling in mutant animal models. This assembled data demonstrate an important role for CRH in neuroendocrine, autonomic, and behavioral correlates of adaptation and maladaptation. Next, we present findings regarding human genetic polymorphisms in CRH pathway genes that are associated with stress and psychiatric disorders. Finally, we discuss a role for regulators of CRH activity as potential sites for therapeutic intervention aimed at treating maladaptive behaviors associated with stress. PMID:23077729

Laryea, Gloria; Arnett, Melinda G; Muglia, Louis J

2012-06-21

141

Genetic and Epigenetic Somatic Alterations in Head and Neck Squamous Cell Carcinomas Are Globally Coordinated but Not Locally Targeted  

Microsoft Academic Search

BackgroundSolid tumors, including head and neck squamous cell carcinomas (HNSCC), arise as a result of genetic and epigenetic alterations in a sustained stress environment. Little work has been done that simultaneously examines the spectrum of both types of changes in human tumors on a genome-wide scale and results so far have been limited and mixed. Since it has been hypothesized

Graham M. Poage; Brock C. Christensen; E. Andres Houseman; Michael D. McClean; John K. Wiencke; Marshall R. Posner; John R. Clark; Heather H. Nelson; Carmen J. Marsit; Karl T. Kelsey; Jörg Hoheisel

2010-01-01

142

Analyses of Genetic Variation in Populations of Oregon Chub, a Threatened Floodplain Minnow in a Highly Altered Environment  

Microsoft Academic Search

The Oregon chub Oregonichthys crameri is a small floodplain minnow endemic to the Willamette River basin of western Oregon. Historically the species was widely abundant and probably relied on periodic floods for dispersal and genetic exchange among populations. The species has declined substantially in the past 100 years due to habitat alterations and the introduction of nonnative species and is

Patrick W. DeHaan; Paul D. Scheerer; Ron Rhew; William R. Ardren

2012-01-01

143

Genetic and Epigenetic Alteration among Three Homoeologous Genes of a Class E MADS Box Gene in Hexaploid Wheat  

Microsoft Academic Search

Bread wheat (Triticum aestivum) is a hexaploid species with A, B, and D ancestral genomes. Most bread wheat genes are present in the genome as triplicated homoeologous genes (homoeologs) derived from the ancestral species. Here, we re- port that both genetic and epigenetic alterations have occurred in the homoeologs of a wheat class E MADS box gene. Two class E

Naoki Shitsukawa; Chikako Tahira; Ken-ichiro Kassai; Chizuru Hirabayashi; Tomoaki Shimizu; Shigeo Takumi; Keiichi Mochida; Kanako Kawaura; Yasunari Ogihara; Koji Murai

2007-01-01

144

Ex situ cultivation affects genetic structure and diversity in arable plants.  

PubMed

Worldwide, botanical gardens cultivate around 80,000 taxa, corresponding to approximately one-quarter of all vascular plants. Most cultivated taxa are, however, held in a small number of collections, and mostly only in small populations. Lack of genetic exchange and stochastic processes in small populations make them susceptible to detrimental genetic effects, which should be most severe in annual species, as sowing cycles are often short. In order to assess whether ex situ cultivation affects genetic diversity of annuals, five annual arable species with similar breeding systems were assessed with 42 in situ populations being compared to 20 ex situ populations using a random amplified polymorphic DNA (RAPD) analysis approach. Population sizes tended to be lower under ex situ cultivation and levels of genetic diversity also tended to be lower in four of the five species, with differences being significant in only two. Ex situ populations showed incomplete representation of alleles found in the wild. The duration of cultivation did not indicate any effect on genetic diversity. This implies that cultivation strategies resulted in different genetic structures in the garden populations. Although not unequivocally pronounced, differences nonetheless imply that conservation strategies in the involved gardens may need improvement. One option is cold storage of seeds, a practice that is not currently followed in the studied ex situ collections. This may reflect that the respective gardens focus on displaying living plant populations. PMID:22882447

Brütting, C; Hensen, I; Wesche, K

2012-08-08

145

Does natural selection alter genetic architecture? An evaluation of quantitative genetic variation among populations of Allonemobiussocius and A. fasciatus  

Microsoft Academic Search

To make long-term predictions using present quantitative genetic theory it is necessary to assume that the genetic variance-covariance matrix (G) remains constant or at least changes by a constant fraction. In this paper we examine the stability of the genetic architecture of two traits known to be subject to natural selection; femur length and ovipositor length in two species of

Roff; Mousseau

1999-01-01

146

Facial affect recognition deficit as a marker of genetic vulnerability to schizophrenia.  

PubMed

The aim of this study was to investigate the possibility that affect recognition impairments are associated with genetic liability to schizophrenia. In a group of 55 unaffected relatives of schizophrenia patients (parents and siblings) we examined the capacity to detect facially expressed emotions and its relationship to schizotypal personality, neurocognitive functioning, and the subject's actual emotional state. The relatives were compared with 103 schizophrenia patients and 99 healthy subjects without any family history of psychoses. Emotional stimuli were nine black-and-white photos of actors, who portrayed six basic emotions as well as interest, contempt, and shame. The results evidenced the affect recognition deficit in relatives, though milder than that in patients themselves. No correlation between the deficit and schizotypal personality measured with SPQ was detected in the group of relatives. Neither cognitive functioning, including attention, verbal memory and linguistic ability, nor actual emotional states accounted for their affect recognition impairments. The results suggest that the facial affect recognition deficit in schizophrenia may be related to genetic predisposition to the disorder and may serve as an endophenotype in molecular-genetic studies. PMID:19476218

Alfimova, Margarita V; Abramova, Lilia I; Barhatova, Aleksandra I; Yumatova, Polina E; Lyachenko, Galina L; Golimbet, Vera E

2009-05-01

147

Genetic manipulation of intraspinal plasticity after spinal cord injury alters the severity of autonomic dysreflexia  

PubMed Central

Severe spinal cord injuries above mid-thoracic levels can lead to a potentially life-threatening hypertensive condition termed autonomic dysreflexia that is often triggered by painful distension of pelvic viscera (bladder or bowel) and consequent sensory fiber activation, including nociceptive C-fibers. Interruption of tonically active medullo-spinal pathways after injury causes disinhibition of thoracolumbar sympathetic preganglionic neurons, and intraspinal sprouting of nerve growth factor (NGF)-responsive primary afferent fibers is thought to contribute to their hyperactivity. We investigated spinal levels that are critical for eliciting autonomic dysreflexia using a model of noxious colorectal distension (CRD) after complete spinal transection at the 4th thoracic segment in rats. Post-traumatic sprouting of calcitonin gene-related peptide (CGRP)-immunoreactive primary afferent fibers was selectively altered at specific spinal levels caudal to the injury with bilateral microinjections of adenovirus encoding the growth-promoting NGF or growth-inhibitory semaphorin 3A (Sema3a) compared to control green fluorescent protein (GFP). Two weeks later, cardio-physiological responses to CRD were assessed among treatment groups prior to histological analysis of afferent fiber density at the injection sites. Dysreflexic hypertension was significantly higher with NGF over-expression in lumboscral segments compared to GFP, whereas similar over-expression of Sema3a significantly reduced noxious CRD-evoked hypertension. Quantitative analysis of CGRP immunostaining in the spinal dorsal horns showed a significant correlation between the extent of fiber sprouting into the spinal segments injected and the severity of autonomic dysreflexia. These results demonstrate that site-directed genetic manipulation of axon guidance molecules after complete spinal cord injury can alter endogenous circuitry in order to modulate plasticity-induced autonomic pathophysiology.

Cameron, Adrian A.; Smith, George M.; Randall, David C.; Brown, David R.; Rabchevsky, Alexander G.

2012-01-01

148

Genetic manipulation of intraspinal plasticity after spinal cord injury alters the severity of autonomic dysreflexia.  

PubMed

Severe spinal cord injuries above mid-thoracic levels can lead to a potentially life-threatening hypertensive condition termed autonomic dysreflexia, which is often triggered by painful distension of pelvic viscera (bladder or bowel) and consequent sensory fiber activation, including nociceptive C-fibers. Interruption of tonically active medullo-spinal pathways after injury causes disinhibition of thoracolumbar sympathetic preganglionic neurons, and intraspinal sprouting of nerve growth factor (NGF)-responsive primary afferent fibers is thought to contribute to their hyperactivity. We investigated spinal levels that are critical for eliciting autonomic dysreflexia using a model of noxious colorectal distension (CRD) after complete spinal transection at the fourth thoracic segment in rats. Post-traumatic sprouting of calcitonin gene-related peptide (CGRP)-immunoreactive primary afferent fibers was selectively altered at specific spinal levels caudal to the injury with bilateral microinjections of adenovirus encoding the growth-promoting NGF or growth-inhibitory semaphorin 3A (Sema3a) compared with control green fluorescent protein (GFP). Two weeks later, cardio-physiological responses to CRD were assessed among treatment groups before histological analysis of afferent fiber density at the injection sites. Dysreflexic hypertension was significantly higher with NGF overexpression in lumbosacral segments compared with GFP, whereas similar overexpression of Sema3a significantly reduced noxious CRD-evoked hypertension. Quantitative analysis of CGRP immunostaining in the spinal dorsal horns showed a significant correlation between the extent of fiber sprouting into the spinal segments injected and the severity of autonomic dysreflexia. These results demonstrate that site-directed genetic manipulation of axon guidance molecules after complete spinal cord injury can alter endogenous circuitry to modulate plasticity-induced autonomic pathophysiology. PMID:16540569

Cameron, Adrian A; Smith, George M; Randall, David C; Brown, David R; Rabchevsky, Alexander G

2006-03-15

149

IDH1 mutation, a genetic alteration associated with adult gliomatosis cerebri.  

PubMed

Recently, mutations in IDH1 and IDH2 have been reported as an early and common genetic alteration in diffuse gliomas, being possibly followed by 1p/19q loss in oligodendrogliomas and TP53 mutations in astrocytomas. Lately, IDH1 mutations have also been identified in adult gliomatosis cerebri (GC). The aim of our study was to test the status of IDH1/2, p53 and of chromosomes 1 and 19 in a series of 12 adult and three pediatric GC. For all tumors, clinico-radiologic characteristics, histopathologic features, status of IDH1/2, p53 and of chromosomes 1 and 19 were evaluated. IDH1 mutations were detected only in GC of adult patients (5/12). They all corresponded to R132H. Additional 1p/19q losses were observed in two of them with histological features of oligodendroglial lineage. Other copy number alterations of chromosomes 1 and 19 were also noticed. The median overall survival in adults was 10.5 months in non-mutated GC and 43.5 months in mutated GC. IDH1 mutations were present in GC of adult patients, but not in those of children. There was a trend toward longer overall survival in mutated GC when compared to non-mutated ones. Concomitant 1p/19q loss was observed in IDH1-mutated GC with oligodendroglial phenotype. These observations contribute toward establishing a stronger link between GC and diffuse glioma. In addition, these results also emphasize the importance of testing for IDH1/2 mutations and 1p/19q deletions in GC to classify them better and to allow the development of targeted therapy. PMID:21481010

Narasimhaiah, Deepti; Miquel, Catherine; Verhamme, Elisabeth; Desclée, Paul; Cosnard, Guy; Godfraind, Catherine

2011-04-11

150

Growing up in an altered magnetic field affects the initial orientation of young homing pigeons  

Microsoft Academic Search

To test whether the sun compass of pigeons is calibrated by the magnetic field, a group of young pigeons was raised in an altered magnetic field in which magnetic north was turned ca. 65o (in 1974 and 1975) and 120o (in 1980) clockwise. They could see the sun only in an abnormal relation to the magnetic field, since they were

Wolfgang Wiltschko; Roswitha Wiltschko; William T. Keeton; Robert Madden

1983-01-01

151

Neonatal phytoestrogen exposure alters oviduct mucosal immune response to pregnancy and affects preimplantation embryo development in the mouse.  

PubMed

Treatment of neonatal mice with the phytoestrogen genistein (50 mg/kg/day) results in complete female infertility caused in part by preimplantation embryo loss in the oviduct between Days 2 and 3 of pregnancy. We previously demonstrated that oviducts of genistein-treated mice are "posteriorized" as compared to control mouse oviducts because they express numerous genes normally restricted to posterior regions of the female reproductive tract (FRT), the cervix and vagina. We report here that neonatal genistein treatment resulted in substantial changes in oviduct expression of genes important for the FRT mucosal immune response, including immunoglobulins, antimicrobials, and chemokines. Some of the altered immune response genes were chronically altered beginning at the time of neonatal genistein treatment, indicating that these alterations were a result of the posteriorization phenotype. Other alterations in oviduct gene expression were observed only in early pregnancy, immediately after the FRT was exposed to inflammatory or antigenic stimuli from ovulation and mating. The oviduct changes affected development of the surviving embryos by increasing the rate of cleavage and decreasing the trophectoderm-to-inner cell mass cell ratio at the blastocyst stage. We conclude that both altered immune responses to pregnancy and deficits in oviduct support for preimplantation embryo development in the neonatal genistein model are likely to contribute to infertility phenotype. PMID:22553218

Jefferson, Wendy N; Padilla-Banks, Elizabeth; Phelps, Jazma Y; Cantor, Amy M; Williams, Carmen J

2012-07-01

152

Neonatal Phytoestrogen Exposure Alters Oviduct Mucosal Immune Response to Pregnancy and Affects Preimplantation Embryo Development in the Mouse1  

PubMed Central

ABSTRACT Treatment of neonatal mice with the phytoestrogen genistein (50 mg/kg/day) results in complete female infertility caused in part by preimplantation embryo loss in the oviduct between Days 2 and 3 of pregnancy. We previously demonstrated that oviducts of genistein-treated mice are “posteriorized” as compared to control mouse oviducts because they express numerous genes normally restricted to posterior regions of the female reproductive tract (FRT), the cervix and vagina. We report here that neonatal genistein treatment resulted in substantial changes in oviduct expression of genes important for the FRT mucosal immune response, including immunoglobulins, antimicrobials, and chemokines. Some of the altered immune response genes were chronically altered beginning at the time of neonatal genistein treatment, indicating that these alterations were a result of the posteriorization phenotype. Other alterations in oviduct gene expression were observed only in early pregnancy, immediately after the FRT was exposed to inflammatory or antigenic stimuli from ovulation and mating. The oviduct changes affected development of the surviving embryos by increasing the rate of cleavage and decreasing the trophectoderm-to-inner cell mass cell ratio at the blastocyst stage. We conclude that both altered immune responses to pregnancy and deficits in oviduct support for preimplantation embryo development in the neonatal genistein model are likely to contribute to infertility phenotype.

Jefferson, Wendy N.; Padilla-Banks, Elizabeth; Phelps, Jazma Y.; Cantor, Amy M.; Williams, Carmen J.

2012-01-01

153

Genetic Modification of Risk Assessment Based on Staging of Preclinical Type 1 Diabetes in Siblings of Affected Children  

Microsoft Academic Search

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 predisposi- tion affects the natural course of preclinical diabetes in ini- tially nondiabetic siblings of affected children. A total of 701 initially unaffected siblings were graded into four stages of preclinical type 1 diabetes based

S. MRENA; K. SAVOLA; P. KULMALA; H. REIJONEN; J. ILONEN; H. K. ÅKERBLOM; M. KNIP

2010-01-01

154

Vitamin D Related Host Genetic Variants Alter HIV Disease Progression in Children.  

PubMed

BACKGROUND:: Vitamin D deficiency is common in HIV infection and has been associated with advanced disease. This study investigated whether vitamin D related genetic variants were associated with disease progression in HIV-infected children. METHODS:: The Fok-I (C/T), Bsm-I (G/A), GC (A/C), DHCR7 (G/T) and CYP2R1 (G/A) genetic variants were detected by RT-PCR in HIV-infected children who participated in the PACTG P152 and P300 protocols which pre-dated the availability of effective combination antiretroviral therapy. The primary endpoints included time to progression to the first HIV-related disease end-point (?2 OI's, weight-growth failure) or death, which constituted the progression-free-survival. Analyses were performed for age >2 years and <2 years separately adjusting for race and treatment effect. RESULTS:: Of the 998 children evaluated, 139 experienced HIV disease progression. For children >2 years, rapid disease progression was associated with the DHCR7 G allele compared to the T allele (G/G vs. T/T: HR=5.0, p=0.035, G/T vs. T/T: HR=4.5, p=0.042, G/G+G/T vs. T/T: HR=4.8, p=0.036), and the Bsm-I A allele compared to the G allele (A/G vs. G/G: HR=2.2, p=0.014 and A/G+A/A vs. G/G: HR=2.0, p=0.026). In children ?2 years, the Bsm-I A allele increased the risk of disease progression in Hispanics (A/A vs. G/A+G/G: HR=2.8, p=0.03; A/A vs. G/G: HR=2.8, p=0.046) and whites (A/A vs. G/G: HR=6.6, p=0.025; A/A vs. G/A+G/G: HR=3.6, p=0.038). CONCLUSIONS:: Vitamin D related host genetic variants that alter the availability and activity of vitamin D are associated with risk of HIV disease progression in children, and may vary by age and race. PMID:23736144

Moodley, Amaran; Qin, Min; Singh, Kumud K; Spector, Stephen A

2013-06-01

155

Genetic alterations of FGF receptors: an emerging field in clinical cancer diagnostics and therapeutics.  

PubMed

Evaluation of: Turner N, Pearson A, Sharpe R et al. FGFR1 amplification drives endocrine therapy resistance and is a therapeutic target in breast cancer. Cancer Res. 70(5), 2085-2094 (2010). FGF receptor (FGFR) family members are aberrantly activated during carcinogenesis due to gene amplification, chromosomal translocation and missense mutation. FGFR1 is preferentially amplified in estrogen receptor-positive breast cancer, whereas FGFR2 is amplified in triple-negative breast cancer and diffuse-type gastric cancer. Gene amplification of FGFRs results in ligand-independent FGFR signaling to RAS-ERK, PI3K-AKT and JAK-STAT cascades due to the overexpression of wild-type or C-terminally deleted FGFRs. Cediranib, TKI258, Ki23057, MK-2461 and brivanib are broad-range tyrosine kinase inhibitors targeting FGFRs and other receptors. Clinical application of small-molecule FGFR inhibitors could improve the prognosis of FGFR-driven cancer patients. Diagnostic detection of tumors with FGFR genetic alterations in primary lesion, peritoneal effusion, pleural effusion and bone marrow is necessary to select patients for FGFR-targeted therapeutics. PMID:20836672

Katoh, Masaru

2010-09-01

156

Supertasting, earaches and head injury: genetics and pathology alter our taste worlds.  

PubMed

Family studies using thresholds showed that PROP (6-n-propylthiouracil) tasting is produced by a dominant allele, T. Nontasters have two recessive alleles and tasters have one or two dominant alleles. The bitterness of suprathreshold PROP and anatomical criteria subdivide tasters into medium and supertasters. Supertasters may be TT tasters, but this has yet to be demonstrated. Supertasters preceive the greatest bitterness and sweetness from many stimuli as well as the greatest oral burn from alcohol and capsaicin. Women are more likely than men to be supertasters. Otitis media and head trauma can alter taste and thus PROP classifications, complicating studies on PROP genetics. Some subjects with a history of otitis media show taste reductions, but others show enhanced tastes and appear to have more taste buds per fungiform papilla. Subjects with head trauma show reduced tastes on some oral loci, but there is evidence that severe reductions on the front of the tongue ameliorate reductions at the circumvallate papillae on the back of the tongue by a release of inhibition mechanism. PMID:8622833

Bartoshuk, L M; Duffy, V B; Reed, D; Williams, A

1996-01-01

157

Detection of complex genetic alterations in human glioblastoma multiforme using comparative genomic hybridization  

SciTech Connect

The aim of the present study was to detect complex genetic alterations in human glioblastoma multiforme (GBM) by comparative genomic in situ hybridization (CGH). Of the 24 GBM that were examined, increased fluorescence intensities indicating chromosomal polysomy of chromosome 7 and gene amplification at chromosome 7p were found in 42% of the tumors. In addition, signal enhancement of chromosome 19 was present in 29% and at 12q13-15 in 21% of the tumors. We also detected reduction of fluorescence intensities indicating gross deletions on chromosomes 10 (58%), 9p (46%), and 13 (29%). There was a close correlation of CGH results when compared with Southern analysis of the EGFR gene localized on chromosome 7 and loss of heterozygosity detection of chromosome 9 and 10 by microsatellite PCR. A close correlation was also observed between copy number changes of chromosome 7 and deletions of chromosome 10. Amplification of chromosome 12q and deletions of chromosomes 9p and 13 seemed to be complementary in the tumors investigated in the present study. 44 refs., 3 figs., 1 tab.

Schlegel, J.; Stumm, G. [Universitaet Marburg (Germany); Scherthan, H.; Arens, N. [Universitaet Kaiderlautern (Germany)] [and others

1996-01-01

158

Evidence That Altered Amygdala Activity in Schizophrenia is Related to Clinical State and Not Genetic Risk  

PubMed Central

Objective Although amygdala dysfunction is reported in schizophrenia, it is unknown whether this deficit represents a heritable phenotype that is related to risk for schizophrenia or whether it is related to disease state. The purpose of the present study was to examine amygdala response to threatening faces among healthy siblings of schizophrenia patients in whom a subtler heritable deficit might be observed. Method Participants were 34 schizophrenia patients, 29 unaffected siblings, and 20 healthy comparison subjects. Blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was conducted during an implicit facial information processing task. The N-back working memory task, which has been shown to elicit prefrontal cortex abnormalities in unaffected siblings of schizophrenia patients, was employed as a positive experimental control. Results Schizophrenia patients demonstrated a deficit in amygdala reactivity to negative face stimuli and an alteration, correlated with neuroleptic drug dosage, in the functional coupling between the amygdala and subgenual cingulate. In contrast, unaffected siblings showed a pattern that was not statistically different from that of healthy comparison subjects. During the N-back working memory task, both schizophrenia patients and their unaffected siblings demonstrated a pattern of inefficient prefrontal cortex engagement, which is consistent with earlier evidence that this pattern is related to genetic risk for schizophrenia. Conclusions These data suggest that the pathophysiological mechanism underlying the inability of individuals with schizophrenia to normally engage the amygdala in processing fearful and angry facial representations is more likely a phenomenon related to the disease state, specifically to treatment.

Rasetti, Roberta; Mattay, Venkata S.; Wiedholz, Lisa M.; Kolachana, Bhaskar S.; Hariri, Ahmad R.; Callicott, Joseph H.; Meyer-Lindenberg, Andreas; Weinberger, Daniel R.

2009-01-01

159

Individual differences in cognition, affect, and performance: Behavioral, neuroimaging, and molecular genetic approaches  

PubMed Central

We describe the use of behavioral, neuroimaging, and genetic methods to examine individual differences in cognition and affect, guided by three criteria: (1) relevance to human performance in work and everyday settings; (2) interactions between working memory, decision-making, and affective processing; and (3) examination of individual differences. The results of behavioral, functional MRI (fMRI), event-related potential (ERP), and molecular genetic studies show that analyses at the group level often mask important findings associated with sub-groups of individuals. Dopaminergic/noradrenergic genes influencing prefrontal cortex activity contribute to inter-individual variation in working memory and decision behavior, including performance in complex simulations of military decision-making. The interactive influences of individual differences in anxiety, sensation seeking, and boredom susceptibility on evaluative decision-making can be systematically described using ERP and fMRI methods. We conclude that a multi-modal neuroergonomic approach to examining brain function (using both neuroimaging and molecular genetics) can be usefully applied to understanding individual differences in cognition and affect and has implications for human performance at work.

Parasuraman, Raja; Jiang, Yang

2012-01-01

160

Experimental alteration of DNA methylation affects the phenotypic plasticity of ecologically relevant traits in Arabidopsis thaliana  

Microsoft Academic Search

Heritable phenotypic variation in plants can be caused not only by underlying genetic differences, but also by variation in\\u000a epigenetic modifications such as DNA methylation. However, we still know very little about how relevant such epigenetic variation\\u000a is to the ecology and evolution of natural populations. We conducted a greenhouse experiment in which we treated a set of\\u000a natural genotypes

Oliver Bossdorf; Davide Arcuri; Christina L. Richards; Massimo Pigliucci

2010-01-01

161

The Protective Effect of Minocycline in a Paraquat-Induced Parkinson's Disease Model in Drosophila is Modified in Altered Genetic Backgrounds  

PubMed Central

Epidemiological studies link the herbicide paraquat to increased incidence of Parkinson's disease (PD). We previously reported that Drosophila exposed to paraquat recapitulate PD symptoms, including region-specific degeneration of dopaminergic neurons. Minocycline, a tetracycline derivative, exerts ameliorative effects in neurodegenerative disease models, including Drosophila. We investigated whether our environmental toxin-based PD model could contribute to an understanding of cellular and genetic mechanisms of minocycline action and whether we could assess potential interference with these drug effects in altered genetic backgrounds. Cofeeding of minocycline with paraquat prolonged survival, rescued mobility defects, blocked generation of reactive oxygen species, and extended dopaminergic neuron survival, as has been reported previously for a genetic model of PD in Drosophila. We then extended this study to identify potential interactions of minocycline with genes regulating dopamine homeostasis that might modify protection against paraquat and found that deficits in GTP cyclohydrolase adversely affect minocycline rescue. We further performed genetic studies to identify signaling pathways that are necessary for minocycline protection against paraquat toxicity and found that mutations in the Drosophila genes that encode c-Jun N-terminal kinase (JNK) and Akt/Protein kinase B block minocycline rescue.

Inamdar, Arati A.; Chaudhuri, Anathbandhu; O'Donnell, Janis

2012-01-01

162

Genetic and pharmacological manipulations that alter metabolism suppress seizure-like activity in Drosophila.  

PubMed

There is increasing evidence that alterations in metabolism can affect seizure susceptibility in a wide range of organisms. In order to investigate the link between metabolism and seizures, we took advantage of a group of Drosophila mutants, the Bang-sensitive (BS) paralytics, which are 3-10 times more susceptible to seizure-like activity (SLA) than wild type flies following a variety of stimuli including mechanical shock. To alter metabolism, we introduced the atsugari (atu) mutation into three of the BS mutants, easily shocked (eas), bang senseless (bss), and technical knockout (tko). The atu mutants, which exhibit reduced expression of the Drosophila ortholog of dystroglycan gene, have previously been shown to have a higher metabolic rate than wild type flies. Following mechanical shock, all three BS;atu double mutants displayed a reduction in SLA and the eas;atu and tko;atu double mutants recovered from the shock quicker than the respective single mutant BS flies. In addition, the eas;atu and tko;atu flies displayed higher levels of metabolism as compared to the single mutant BS flies. To further study the correlation between metabolism and seizure susceptibility, the three BS strains were fed a sulfonylurea drug (tolbutamide) known to both increase heamolymph glucose concentrations and stimulate lipid metabolism in flies. Following mechanical shock, the eas and tko mutants fed tolbutamide displayed less SLA and recovered quicker than unfed flies. While the bss mutants fed tolbutamide did not display a reduction in SLA, they did recover quicker than unfed controls. These data indicate that the upregulation of metabolism can have a protective effect against seizure susceptibility, a result that suggests new avenues for possible drug development. PMID:23247062

Stone, Bryan; Evans, Leah; Coleman, John; Kuebler, Daniel

2012-12-13

163

Altered membrane fatty acids of cultured human retinal pigment epithelium persistently infected with rubella virus may affect secondary cellular function.  

PubMed

Persistent infection with rubella virus (RV) can alter secondary functions of host cells. Previously we had documented defective phagocytosis of latex beads by cultured human retinal pigment epithelial cells (RPE), persistently infected with M-33 RV (RPE/RV). Here, examining possible mechanisms for altered function, we reported significant differences between the total esterified fatty acids (FA) of RPE and RPE/RV membranes, measured by gas liquid chromatography. RPE/RV contained an increased proportion of saturated FA, particularly palmitic acid, with a presence of unusual chromatographic FA peaks co-eluting with odd-numbered long-chain carbon atom FA not normally found in human cells. Apical membrane microvilli, structures essential to phagocytic activity of RPE and RPE/RV, observed by scanning and transmission electron microscopy, were similar in number and appearance between uninfected RPE and RPE/RV cells before and after latex bead addition. However, RPE/RV microvilli, possibly reflecting altered membrane FA composition, engaged latex beads less effectively than uninfected RPE microvilli. In addition, microvilli remained abnormally distributed on RPE/RV cell surfaces at 48 h after latex addition. Thus, RV persistent infection may affect the cellular membrane fluidity and functional activity of human cells with increased saturated FA proportions and altered FA components of membrane phospholipids. These changes may participate in the defective phagocytosis of RPE/RV. PMID:8129623

Williams, L L; Lew, H M; Davidorf, F H; Pelok, S G; Singley, C T; Wolinsky, J S

1994-01-01

164

Plant genetics affects arthropod community richness and composition: evidence from a synthetic eucalypt hybrid population.  

PubMed

To examine how genetic variation in a plant population affects arthropod community richness and composition, we quantified the arthropod communities on a synthetic population of Eucalyptus amygdalina, E. risdonii, and their F1 and advanced-generation hybrids. Five major patterns emerged. First, the pure species and hybrid populations supported significantly different communities. Second, species richness was significantly greatest on hybrids (F1 > F2 > E. amygdalina > E. risdonii). These results are similar to those from a wild population of the same species and represent the first case in which both synthetic and wild population studies confirm a genetic component to community structure. Hybrids also acted as centers of biodiversity by accumulating both the common and specialist taxa of both parental species (100% in the wild and 80% in the synthetic population). Third, species richness was significantly greater on F1s than the single F2 family, suggesting that the increased insect abundance on hybrids may not be caused by the breakup of coadapted gene complexes. Fourth, specialist arthropod taxa were most likely to show a dominance response to F1 hybrids, whereas generalist taxa exhibited a susceptible response. Fifth, in an analysis of 31 leaf terpenoids that are thought to play a role in plant defense, hybrids were generally intermediate to the parental chemotypes. Within the single F2 family, we found significant associations between the communities of individual trees and five individual oil components, including oil yield, demonstrating that there is a genetic effect on plant defensive chemistry that, in turn, may affect community structure. These studies argue that hybridization has important community-level consequences and that the genetic variation present in hybrid zones can be used to explore the genetic-based mechanisms that structure communities. PMID:11209771

Dungey, H S; Potts, B M; Whitham, T G; Li, H F

2000-12-01

165

Genetic modification of iron metabolism in mice affects the gut microbiota.  

PubMed

The composition of the gut microbiota is affected by environmental factors as well as host genetics. Iron is one of the important elements essential for bacterial growth, thus we hypothesized that changes in host iron homeostasis, may affect the luminal iron content of the gut and thereby the composition of intestinal bacteria. The iron regulatory protein 2 (Irp2) and one of the genes mutated in hereditary hemochromatosis Hfe , are both proteins involved in the regulation of systemic iron homeostasis. To test our hypothesis, fecal metal content and a selected spectrum of the fecal microbiota were analyzed from Hfe-/-, Irp2-/- and their wild type control mice. Elevated levels of iron as well as other minerals in feces of Irp2-/- mice compared to wild type and Hfe-/- mice were observed. Interestingly significant variation in the general fecal-bacterial population-patterns was observed between Irp2-/- and Hfe-/- mice. Furthermore the relative abundance of five species, mainly lactic acid bacteria, was significantly different among the mouse lines. Lactobacillus (L.) murinus and L. intestinalis were highly abundant in Irp2-/- mice, Enterococcus faecium species cluster and a species most similar to Olsenella were highly abundant in Hfe-/- mice and L. johnsonii was highly abundant in the wild type mice. These results suggest that deletion of iron metabolism genes in the mouse host affects the composition of its intestinal bacteria. Further studying the relationship between gut microbiota and genetic mutations affecting systemic iron metabolism in human should lead to clinical implications. PMID:22580926

Buhnik-Rosenblau, Keren; Moshe-Belizowski, Shirly; Danin-Poleg, Yael; Meyron-Holtz, Esther G

2012-05-13

166

Alterations in affective processing of attack images following September 11, 2001.  

PubMed

The events of September 11, 2001 created unprecedented uncertainty about safety in the United States and created an aftermath with significant psychological impact across the world. This study examined emotional information encoding in 31 healthy individuals whose stress response symptoms ranged from none to a moderate level shortly after the attacks as assessed by the Impact of Event Scale-Revised. Participants viewed attack-related, negative (but attack-irrelevant), and neutral images while their event-related brain potentials (ERPs) were recorded. Attack images elicited enhanced P300 relative to negative and neutral images, and emotional images prompted larger slow waves than neutral images did. Total symptoms were correlated with altered N2, P300, and slow wave responses during valence processing. Specifically, hyperarousal and intrusion symptoms were associated with diminished stimulus discrimination between neutral and unpleasant images; avoidance symptoms were associated with hypervigilance, as suggested by reduced P300 difference between attack and other images and reduced appraisal of attack images as indicated by attenuated slow wave. The findings in this minimally symptomatic sample are compatible with the alterations in cognition in the posttraumatic stress disorder (PTSD) literature and are consistent with a dimensional model of PTSD. PMID:21882249

Tso, Ivy F; Chiu, Pearl H; King-Casas, Brooks R; Deldin, Patricia J

2011-08-31

167

Association between Oro-Facial Defects and Systemic Alterations in Children Affected by Marfan Syndrome.  

PubMed

Background: It is important to establish an early diagnosis of the Marfan Syndrome (MFS) for providing an adequate pharmacological or surgical therapy. Nevertheless, this diagnosis may be complex, given the multi-organic involvement of this disease. Aims: In this work, we evaluated the oral phenotype in a group of paediatric patients with a clinical diagnosis of MFS, to quantify the association of the oro-facial defects with other systemic alterations. Settings and Design: Paediatric subjects who were aged, with a clinical diagnosis of MFS, were selected from our regional Marfan monitoring unit. Methods and Material: All the patients were subjected to Paediatric Dentistry examinations and a radiological screening with Panoramic and Cephalometric X-Rays. The aortic dilation (Aortic Z-score value), the hyperlaxity of the ligaments and scoliosis were evaluated by cardio-surgical and orthopaedics specialists. Statistical Analysis: The correlations between the oral and systemic alterations were analyzed by using the chi square test for the nominal variables. Results and Conclusions: We found a significant correlation of the Aortic Z - score with multiple oral defects which included retrognathia, malar hypoplasia, cross bite, oral respiration and an ogival palate. An association of the oral defects with hyperlaxity of the ligaments and scoliosis was also found. Thus, the data suggested that dentists should be more involved in a multidisciplinary approach, to provide an early MFS diagnosis in paediatric patients. PMID:23730650

Docimo, Raffaella; Maturo, Paolo; D'Auria, Francesca; Grego, Susanna; Costacurta, Micaela; Perugia, Cesare; Chiariello, Luigi

2013-04-01

168

Early Experiences Can Alter Gene Expression and Affect Long-Term Development. Working Paper #10  

ERIC Educational Resources Information Center

|New scientific research shows that environmental influences can actually affect whether and how genes are expressed. Thus, the old ideas that genes are "set in stone" or that they alone determine development have been disproven. In fact, scientists have discovered that early experiences can determine how genes are turned on and off and even…

National Scientific Council on the Developing Child, 2010

2010-01-01

169

Altered visual experience and acute visual deprivation affect predatory targeting by infrared-imaging Boid snakes  

Microsoft Academic Search

Boid and Crotaline snakes use both their eyes and infrared-imaging facial pit organs to target homeothermic prey. These snakes can target in complete darkness, but the eyes can also effectively direct predatory strikes. We investigated the behavioral correlates of boid snakes’ simultaneous use of two imaging systems by testing whether congenital unilateral visual deprivation affects targeting performance. Normally sighted Burmese

Michael S. Grace; Owen M. Woodward

2001-01-01

170

Altered affective, executive and sensorimotor resting state networks in patients with pediatric mania  

PubMed Central

Background The aim of the present study was to map the pathophysiology of resting state functional connectivity accompanying structural and functional abnormalities in children with bipolar disorder. Methods Children with bipolar disorder and demographically matched healthy controls underwent resting-state functional magnetic resonance imaging. A model-free independent component analysis was performed to identify intrinsically interconnected networks. Results We included 34 children with bipolar disorder and 40 controls in our analysis. Three distinct resting state networks corresponding to affective, executive and sensorimotor functions emerged as being significantly different between the pediatric bipolar disorder (PBD) and control groups. All 3 networks showed hyperconnectivity in the PBD relative to the control group. Specifically, the connectivity of the dorsal anterior cingulate cortex (ACC) differentiated the PBD from the control group in both the affective and the executive networks. Exploratory analysis suggests that greater connectivity of the right amygdala within the affective network is associated with better executive function in children with bipolar disorder, but not in controls. Limitations Unique clinical characteristics of the study sample allowed us to evaluate the pathophysiology of resting state connectivity at an early state of PBD, which led to the lack of generalizability in terms of comorbid disorders existing in a typical PBD population. Conclusion Abnormally engaged resting state affective, executive and sensorimotor networks observed in children with bipolar disorder may reflect a biological context in which abnormal task-based brain activity can occur. Dual engagement of the dorsal ACC in affective and executive networks supports the neuroanatomical interface of these networks, and the amygdala’s engagement in moderating executive function illustrates the intricate interplay of these neural operations at rest.

Wu, Minjie; Lu, Lisa H.; Passarotti, Alessandra M.; Wegbreit, Ezra; Fitzgerald, Jacklynn; Pavuluri, Mani N.

2013-01-01

171

Meiosis error and subsequent genetic and epigenetic alterations invoke the malignant transformation of germ cell tumor.  

PubMed

Germ cell tumors (GCTs) are thought to arise from primordial germ cells (PGCs) that undergo epigenetic reprogramming. To explore the mechanisms of GCT formation, we analyzed single-nucleotide polymorphism array comparative genomic hybridization patterns and the methylation status of 15 tumor suppressor genes (TSGs) and differentially methylated regions (DMRs) of two imprinted genes, H19 and SNRPN, in 28 children with GCTs. Three GCTs with 25-26 segmental uniparental disomies (UPDs), heterozygous centromeric regions, and a highly methylated SNRPN DMR may have occurred through meiosis I error. Three other GCTs with whole UPD and homozygous centromeric regions of all chromosomes may have occurred through endoreduplication of a haploid set in an ovum or testis. The other 22 GCTs had heterozygous centromeric regions of all chromosomes and no or a small number of segmental or whole UPDs and may have developed from premeiotic PGCs before imprint erasure or a reestablishment of imprinting. Gain and amplification of 3p24-p22 and 20q13-q13, and loss and UPD of 1p36-p35, 4q21-q21, 5q11-q13, and 6q26-qter were found in five or more tumors. 1p36-p35 loss was frequent, and found in 19 tumors; RUNX3 residing at 1p36 was methylated in the promoter regions of 16 tumors. Two yolk sac tumors with many segmental UPDs or whole UPD of all chromosomes had gain of 20q13-q13 and loss of 1p36-p35, and seven or eight methylated TSGs. These genetic and epigenetic alterations may have caused malignant transformation because they were rarely found in teratomas with segmental or whole UPDs. PMID:23225212

Ichikawa, Mizuho; Arai, Yasuhito; Haruta, Masayuki; Furukawa, Shinsuke; Ariga, Tadashi; Kajii, Tadashi; Kaneko, Yasuhiko

2012-12-08

172

Anthropogenic alterations of genetic diversity within tree populations: Implications for forest ecosystem resilience  

Microsoft Academic Search

Healthy forests provide many of the essential ecosystem services upon which all life depends. Genetic diversity is an essential component of long-term forest health because it provides a basis for adaptation and resilience to environmental stress and change. In addition to natural processes, numerous anthropogenic factors deplete forest genetic resources. Genetic losses could be particularly consequential now because robust resilience

Paul G. Schaberg; Donald H. DeHayes; Gary J. Hawley; Samuel E. Nijensohn

2008-01-01

173

Can sexual dimorphism and body shape be altered in Nile tilapia ( Oreochromis niloticus) by genetic means?  

Microsoft Academic Search

The objective of this study was to estimate genetic parameters in GIFT (Genetically Improved Farmed Tilapia), especially focusing on the genetic correlation between trait expressions in both sexes and among measurements of body size. Body weight, length, depth and width data at harvest from 12,308 individuals, progeny of 232 sires and 340 dams, were analyzed by restricted maximum likelihood methods fitting

Nguyen Hong Nguyen; Hooi Ling Khaw; Raul W. Ponzoni; Azhar Hamzah; Norhidayat Kamaruzzaman

2007-01-01

174

Altered Cohesin Gene Dosage Affects Mammalian Meiotic Chromosome Structure and Behavior  

PubMed Central

Based on studies in mice and humans, cohesin loss from chromosomes during the period of protracted meiotic arrest appears to play a major role in chromosome segregation errors during female meiosis. In mice, mutations in meiosis-specific cohesin genes cause meiotic disturbances and infertility. However, the more clinically relevant situation, heterozygosity for mutations in these genes, has not been evaluated. We report here evidence from the mouse that partial loss of gene function for either Smc1b or Rec8 causes perturbations in the formation of the synaptonemal complex (SC) and affects both synapsis and recombination between homologs during meiotic prophase. Importantly, these defects increase the frequency of chromosomally abnormal eggs in the adult female. These findings have important implications for humans: they suggest that women who carry mutations or variants that affect cohesin function have an elevated risk of aneuploid pregnancies and may even be at increased risk of transmitting structural chromosome abnormalities.

Stevense, Michelle; Smith, Helen; Nagaoka, So; Hassold, Terry; McKay, Michael; Xu, Huiling; Fu, Jun; Revenkova, Ekaterina; Jessberger, Rolf; Hunt, Patricia

2013-01-01

175

The diagnosis and management of pre-invasive breast disease: Genetic alterations in pre-invasive lesions  

Microsoft Academic Search

The development of modern molecular genetic techniques has allowed breast cancer researchers to clarify the multistep model of breast carcinogenesis. Laser capture microdissection coupled with comparative genomic hybridisation and\\/or loss-of-heterozygosity methods have confirmed that many pre-invasive lesions of the breast harbour chromosomal abnormalities at loci known to be altered in invasive breast carcinomas. Current data do not provide strong evidence

Jorge S Reis-Filho; Sunil R Lakhani

2003-01-01

176

Alteration of affective Theory of Mind in amnestic mild cognitive impairment.  

PubMed

The concept of amnestic mild cognitive impairment (aMCI) concerns a population of older individuals at high risk of developing probable Alzheimer's disease (AD). Impairments of the cognitive component of Theory of Mind (ToM), that is the inference about other people's beliefs, have been well documented in AD; on the contrary, controversial findings have been reported on the affective component of ToM (inference about other's feelings), a process mainly based on medial portions of the prefrontal cortex. The current study aimed at evaluating the affective component of ToM in aMCI subjects. Twenty aMCI subjects and 20 age-matched healthy controls (HC) underwent a standard neuropsychological assessment and the assessment of affective ToM with the full 36-item version of reading the mind in the eyes (RME). Although aMCI subjects had formal impaired performances only in memory tasks, HC outperformed aMCI subjects in several cognitive tasks, including also the RME (mean RME scores 21.7 ± 3.0 vs. 17.0 ± 3.8%; 60.3% of correct answers vs. 47.2%). The lower RME performance of aMCI patients provides the first empirical evidence that aMCI may be associated with difficulties in tasks of affective ToM, in accordance with recent findings of early difficulties of aMCI patients in other processes that are mainly dependent on the medial prefrontal cortex, such as reversal learning and decision making under ambiguity. Findings of the current study need further empirical confirmation in larger samples of aMCI patients and also the investigation of other MCI subtypes is needed. PMID:23126311

Poletti, Michele; Bonuccelli, Ubaldo

2012-11-05

177

Human erythroid cells are affected by aluminium. Alteration of membrane band 3 protein  

Microsoft Academic Search

There is evidence that anaemia is associated with aluminium (Al). We have already reported on the sensitivity to Al, showed by erythroid cell populations of animals chronically exposed to the metal. In order to investigate whether Al could also affect human cells, experiments were carried out both on immature and mature human erythroid cells. Erythroid progenitors (CFU-E, colony-forming units-erythroid) concentrated

Daniela Vittori; Graciela Garbossa; Carlos Lafourcade; Gladys Pérez; Alcira Nesse

2002-01-01

178

Accelerated post-glucose glycaemia and altered alliesthesia-test in Seasonal Affective Disorder  

Microsoft Academic Search

Background: Little is known about the link between mood, food and metabolic function in Seasonal Affective Disorder (SAD). Methods: We investigated this link in a combined glucose tolerance–alliesthesia test in eight SAD patients in winter before and after one week light therapy, and in summer. Results: SAD patients exhibited faster post-glucose glycaemic and insulin responses (p<0.05), and increased hedonic ratings

Kurt Kräuchi; Ulrich Keller; Georg Leonhardt; Daniel P. Brunner; Peter van der Velde; Hans-Joachim Haug; Anna Wirz-Justice

1999-01-01

179

Preschool-Aged Children with Iron Deficiency Anemia Show Altered Affect and Behavior1,2  

Microsoft Academic Search

This study compared social looking and response to novelty in preschool-aged children (47-68 mo) with or without iron deficiency anemia (IDA). Iron status of the participants from a low-income community in New Delhi, India, was based on venous hemoglobin, mean corpuscular volume, and red cell distribution width. Children's social looking toward adults, affect, and wary or hesitant behavior in response

Betsy Lozoff; Matthew J. Burden; Niko Kaciroti; Rosa Angulo-Barroso; Sunil Sazawal

180

Elevated CO2 affects predator-prey interactions through altered performance.  

PubMed

Recent research has shown that exposure to elevated carbon dioxide (CO2) affects how fishes perceive their environment, affecting behavioral and cognitive processes leading to increased prey mortality. However, it is unclear if increased mortality results from changes in the dynamics of predator-prey interactions or due to prey increasing activity levels. Here we demonstrate that ocean pCO2 projected to occur by 2100 significantly effects the interactions of a predator-prey pair of common reef fish: the planktivorous damselfish Pomacentrus amboinensis and the piscivorous dottyback Pseudochromis fuscus. Prey exposed to elevated CO2 (880 µatm) or a present-day control (440 µatm) interacted with similarly exposed predators in a cross-factored design. Predators had the lowest capture success when exposed to elevated CO2 and interacting with prey exposed to present-day CO2. Prey exposed to elevated CO2 had reduced escape distances and longer reaction distances compared to prey exposed to present-day CO2 conditions, but this was dependent on whether the prey was paired with a CO2 exposed predator or not. This suggests that the dynamics of predator-prey interactions under future CO2 environments will depend on the extent to which the interacting species are affected and can adapt to the adverse effects of elevated CO2. PMID:23484032

Allan, Bridie J M; Domenici, Paolo; McCormick, Mark I; Watson, Sue-Ann; Munday, Philip L

2013-03-06

181

Relationships between protein and mineral during enamel development in normal and genetically altered mice.  

PubMed

The purpose of this study was to quantify and compare the amounts of volatiles (mostly protein) and mineral present in developing incisor enamel in normal mice and in those genetically engineered for absence of intact enamelin, ameloblastin, matrix metalloproteinase 20 (MMP20) or kallikrein-related peptidase 4 (KLK4). Data indicated that all mice showed peaks in the gross weight of volatiles and a similar weight of mineral at locations on incisors normally associated with early maturation. Thereafter, the content of volatiles on normal incisors declined rapidly by as much as 62%, but not by 100%, over 2 mm, accompanied by increases of ? threefold in mineral weights. Enamelin heterozygous mice (lower incisors) showed a decrease in volatile content across the maturation stage, yet mineral failed to increase significantly. Mmp20 null mice showed no significant loss of volatiles from maturing enamel, yet the amount of mineral increased. Klk4 null mice showed normal mineral acquisition up to early maturation, but the input of new volatiles in mid to late maturation caused the final mineralization to slow below normal levels. These results suggest that it is not only the amount of protein but also the nature or type of protein or fragments present in the local crystallite environment that affects their volumetric expansion as they mature. PMID:22243238

Smith, Charles E; Hu, Yuanyuan; Richardson, Amelia S; Bartlett, John D; Hu, Jan C-C; Simmer, James P

2011-12-01

182

Relationships between protein and mineral during enamel development in normal and genetically altered mice  

PubMed Central

The purpose of this study was to quantify and compare the amounts of volatiles (mostly protein) and mineral present in developing incisor enamel in normal mice and in those genetically engineered for absence of intact enamelin, ameloblastin, matrix metalloproteinase 20 (MMP20) or kallikrein-related peptidase 4 (KLK4). Data indicated that all mice showed peaks in the gross weight of volatiles and a similar weight of mineral at locations on incisors normally associated with early maturation. Thereafter, the content of volatiles on normal incisors declined rapidly by as much as 62%, but not by 100%, over 2 mm, accompanied by increases of ~threefold in mineral weights. Enamelin heterozygous mice (lower incisors) showed a decrease in volatile content across the maturation stage, yet mineral failed to increase significantly. Mmp20 null mice showed no significant loss of volatiles from maturing enamel, yet the amount of mineral increased. Klk4 null mice showed normal mineral acquisition up to early maturation, but the input of new volatiles in mid to late maturation caused the final mineralization to slow below normal levels. These results suggest that it is not only the amount of protein but also the nature or type of protein or fragments present in the local crystallite environment that affects their volumetric expansion as they mature.

Smith, Charles E.; Hu, Yuanyuan; Richardson, Amelia S.; Bartlett, John D.; Hu, Jan C-C.; Simmer, James P.

2012-01-01

183

Genetic epidemiology of mutated K-ras proto-oncogene, altered suppressor genes, and microsatellite instability in colorectal adenomas  

PubMed Central

BACKGROUND—The genetic epidemiology of colorectal adenomas has not been studied prospectively in colonoscopy patients without cancer.?AIMS—To study genetic alterations in colorectal adenomas and correlate these with patient demographics and adenoma characteristics.?METHODS—Mutations and allelic deletions in 201 adenomas from 60 patients were compared with demographic features, adenoma characteristics, and family history.?RESULTS—The most common alteration was K-ras proto-oncogene mutation, present in 35% of adenomas and 65% of patients. Patients 65 years of age and older had a decreased probability of K-ras mutations (26% versus 45%). Overexpression of p53 gene product was present in only 6% of adenomas but was more frequent in villous or tubulovillous adenomas (19% versus 3%). Allelic loss of chromosome 18q was present in only 2% of adenomas and was significantly less frequent than p53 overexpression. DNA replication errors (RER) were present in 7% of adenomas and 15% of patients, including multiple adenomas in four patients (two with hereditary non-polyposis colorectal cancer syndrome). Only 36% of RER positive adenomas had alteration of BAT-26 alleles, none had alteration of BAT-25, and only one (8%) had mutation in the transforming growth factor ? type II receptor gene. RER positive adenomas were more likely to have a K-ras mutation. In patients with multiple adenomas, there was concordance of p53 overexpression and RER but not of K-ras mutations. ?CONCLUSIONS—Genetic progression in colorectal adenomas is heterogeneous, involving factors related to patient age and the presence of RER for the occurrence of ras mutations, but different intraindividual characteristics for the occurrence of p53 alterations and RER.???Keywords: K-ras mutation; p53 gene; loss of 18q; microsatellite instability; replication error; TGF?RII

Rashid, A; Zahurak, M; Goodman, S; Hamilton, S

1999-01-01

184

Identification of genetic loci affecting the establishment and development of Echinococcus multilocularis larvae in mice.  

PubMed

Alveolar echinococcosis (AE) is a severe hepatic disorder caused by larval infection by the fox tapeworm Echinococcus multilocularis. The course of parasitic development and host reactions are known to vary significantly among host species, and even among different inbred strains of mice. As reported previously, after oral administration of parasite eggs, DBA/2 (D2) mice showed a higher rate of cyst establishment and more advanced protoscolex development in the liver than C57BL/6 (B6) mice. These findings strongly suggest that the outcome of AE is affected by host genetic factor(s). In the present study, the genetic basis of such strain-specific differences in susceptibility/resistance to AE in murine models was studied by whole-genome scanning for quantitative trait loci (QTLs) using a backcross of (B6×D2)F(1) and D2 mice with varying susceptibility to E. multilocularis infection. For cyst establishment, genome linkage analysis identified one suggestive and one significant QTL on chromosomes (Chrs.) 9 and 6, respectively, whereas for protoscolex development, two suggestive and one highly significant QTLs were detected on Chrs. 6, 17 and 1, respectively. Our QTL analyses using murine AE models revealed that multiple genetic factors regulated host susceptibility/resistance to E. multilocularis infection. Moreover, our findings show that establishment of the parasite cysts in the liver is affected by QTLs that are distinct from those associated with the subsequent protoscolex development of the parasite, indicating that different host factors are involved in the host-parasite interplay at each developmental stage of the larval parasite. Further identification of responsible genes located on the identified QTLs could lead to the development of effective disease prevention and control strategies, including an intensive screening and clinical follow-up of genetically high-risk groups for AE infection. PMID:21835179

Nakao, Ryo; Kameda, Yayoi; Kouguchi, Hirokazu; Matsumoto, Jun; Dang, Zhisheng; Simon, Ayo Yila; Torigoe, Daisuke; Sasaki, Nobuya; Oku, Yuzaburo; Sugimoto, Chihiro; Agui, Takashi; Yagi, Kinpei

2011-07-26

185

Haplotype structure strongly affects recombination in a maize genetic interval polymorphic for Helitron and retrotransposon insertions  

PubMed Central

We have asked here how the remarkable variation in maize haplotype structure affects recombination. We compared recombination across a genetic interval of 9S in 2 highly dissimilar heterozygotes that shared 1 parent. The genetic interval in the common haplotype is ?100 kb long and contains 6 genes interspersed with gene-fragment-bearing Helitrons and retrotransposons that, together, comprise 70% of its length. In one heterozygote, most intergenic insertions are homozygous, although polymorphic, enabling us to determine whether any recombination junctions fall within them. In the other, most intergenic insertions are hemizygous and, thus, incapable of homologous recombination. Our analysis of the frequency and distribution of recombination in the interval revealed that: (i) Most junctions were circumscribed to the gene space, where they showed a highly nonuniform distribution. In both heterozygotes, more than half of the junctions fell in the stc1 gene, making it a clear recombination hotspot in the region. However, the genetic size of stc1 was 2-fold lower when flanked by a hemizygous 25-kb retrotransposon cluster. (ii) No junctions fell in the hypro1 gene in either heterozygote, making it a genic recombination coldspot. (iii) No recombination occurred within the gene fragments borne on Helitrons nor within retrotransposons, so neither insertion class contributes to the interval's genetic length. (iv) Unexpectedly, several junctions fell in an intergenic region not shared by all 3 haplotypes. (v) In general, the ability of a sequence to recombine correlated inversely with its methylation status. Our results show that haplotypic structural variability strongly affects the frequency and distribution of recombination events in maize.

He, Limei; Dooner, Hugo K.

2009-01-01

186

Alterations in affective behavior during the time course of alcohol hangover.  

PubMed

Alcohol hangover is a temporary state described as the unpleasant next-day effects after binge-like drinking. Hangover begins when ethanol is absent in plasma and is characterized by physical and psychological symptoms. Affective behavior is impaired during the acute phase of alcohol intoxication; however, no reports indicate if similar effects are observed during withdrawal. The aim of this work was to study the time-extension and possible fluctuations in affective behavior during a hangover episode. Male Swiss mice were injected i.p. either with saline (control group) or with ethanol (3.8g/kg BW) (hangover group). Anxiety, fear-related behavior and despair phenotype were evaluated at a basal point (ZT0) and every 2h up to 20h after blood alcohol levels were close to zero (hangover onset). Also, anhedonia signs and pain perception disabilities were studied. Mice exhibited an increase in anxiety-like behavior during 4h and 14h after hangover onset when evaluated by the elevated-plus maze and open field test respectively (p<0.05). Fear-related behavior was detected in hangover animals by the increase of freezing and decrease of line crossings and rearing frequency during 16h after hangover onset (p<0.001). Depression signs were found in hangover mice during 14h (p<0.05). Hangover mice showed a significant decrease in pain perception when tested by tail immersion test at the beginning of hangover (p<0.05). Our findings demonstrate a time-extension between 14 and 16h for hangover affective impairments. This study shows the long lasting effects of hangover over the phase of ethanol intoxication. PMID:23850352

Karadayian, Analía G; Busso, María J; Feleder, Carlos; Cutrera, Rodolfo A

2013-07-11

187

Natural Selection Affects Multiple Aspects of Genetic Variation at Putatively Neutral Sites across the Human Genome  

PubMed Central

A major question in evolutionary biology is how natural selection has shaped patterns of genetic variation across the human genome. Previous work has documented a reduction in genetic diversity in regions of the genome with low recombination rates. However, it is unclear whether other summaries of genetic variation, like allele frequencies, are also correlated with recombination rate and whether these correlations can be explained solely by negative selection against deleterious mutations or whether positive selection acting on favorable alleles is also required. Here we attempt to address these questions by analyzing three different genome-wide resequencing datasets from European individuals. We document several significant correlations between different genomic features. In particular, we find that average minor allele frequency and diversity are reduced in regions of low recombination and that human diversity, human-chimp divergence, and average minor allele frequency are reduced near genes. Population genetic simulations show that either positive natural selection acting on favorable mutations or negative natural selection acting against deleterious mutations can explain these correlations. However, models with strong positive selection on nonsynonymous mutations and little negative selection predict a stronger negative correlation between neutral diversity and nonsynonymous divergence than observed in the actual data, supporting the importance of negative, rather than positive, selection throughout the genome. Further, we show that the widespread presence of weakly deleterious alleles, rather than a small number of strongly positively selected mutations, is responsible for the correlation between neutral genetic diversity and recombination rate. This work suggests that natural selection has affected multiple aspects of linked neutral variation throughout the human genome and that positive selection is not required to explain these observations.

Lohmueller, Kirk E.; Albrechtsen, Anders; Li, Yingrui; Kim, Su Yeon; Korneliussen, Thorfinn; Vinckenbosch, Nicolas; Tian, Geng; Huerta-Sanchez, Emilia; Feder, Alison F.; Grarup, Niels; J?rgensen, Torben; Jiang, Tao; Witte, Daniel R.; Sandbaek, Annelli; Hellmann, Ines; Lauritzen, Torsten; Hansen, Torben

2011-01-01

188

Altered regulatory mechanisms governing cell survival in children affected with clustering of autoimmune disorders  

PubMed Central

Clustering of Autoimmune Diseases (CAD) is now emerging as a novel clinical entity within monogenic immune defects with a high familial occurrence. Aim of this study is to evaluate the regulatory mechanisms governing cell survival, paying a particular attention to Fas-induced apoptosis, in a cohort of 23 children affected with CAD. In 14 patients, Fas stimulation failed to induce cell apoptosis and in 1 case it was associated with Fas gene mutation. Our study highlights the importance to evaluate cell apoptosis in the group of children with CAD, which, with this regard, represents a distinct clinical entity.

2012-01-01

189

Endosulfan affects health variables in adult zebrafish (Danio rerio) and induces alterations in larvae development.  

PubMed

Adult zebrafish (Danio rerio) were exposed to 0 (control), 0.16 or 0.48?g/L of the insecticide, endosulfan, for 28days. Haematology, whole body ions, thiobarbituric acid reactive substances (TBARS), Na(+)K(+)-ATPase, organ histology and reproduction were assessed in adults. The resulting offspring were examined for latent effects on development (heart rate and morphometrics). On day 14, adult fish exposed to 0.16?g/L endosulfan showed significantly lower red blood cell counts than those exposed to 0.48?g/L endosulfan; adult fish exposed to 0.16 ug/L also showed elevated TBARS compared to controls. Both concentrations of endosulfan caused a 4.0 fold increase in Na(+)K(+)-ATPase activity compared to controls (ANOVA, p<0.05). On day 14, the livers of fish exposed to endosulfan had fewer, enlarged hepatocytes, with cell diameters greater than the controls (ANOVA, p<0.05). Morphological alterations in the progeny of fish exposed to endosulfan were observed. Heart beat frequency was significantly lower in larvae from exposed adults to 0.16 ?g/L compared to the control (ANOVA, p<0.05). These findings show that sublethal exposure to endosulfan causes adverse sublethal effects in adult D. rerio, and effects on the development of their offspring. PMID:21262389

Velasco-Santamaría, Yohana M; Handy, Richard D; Sloman, Katherine A

2011-01-22

190

Delineation of Behavioral Phenotypes in Genetic Syndromes: Characteristics of Autism Spectrum Disorder, Affect and Hyperactivity  

Microsoft Academic Search

We investigated autism spectrum disorder (ASD) symptomatology, hyperactivity and affect in seven genetic syndromes; Angelman\\u000a (AS; n = 104), Cri du Chat (CdCS; 58), Cornelia de Lange (CdLS; 101), Fragile X (FXS; 191), Prader-Willi (PWS; 189), Smith-Magenis\\u000a (SMS; 42) and Lowe (LS; 56) syndromes (age range 4–51). ASD symptomatology was heightened in CdLS and FXS. High levels of\\u000a impulsivity were seen in

Chris Oliver; Katy Berg; Jo Moss; Kate Arron; Cheryl Burbidge

191

A Decade of Genetic Counseling in Frontotemporal Dementia Affected Families: Few Counseling Requests and much Familial Opposition to Testing  

Microsoft Academic Search

A decade of genetic counseling of frontotemporal dementia (FTD) affected families has generated two important observations.\\u000a First, the uptake rate for presymptomatic testing for FTD is low in our department of Clinical Genetics at the Erasmus Medical\\u000a Center in the Netherlands. Second, FTD at-risk counselees reported substantial familial opposition to genetic testing, which\\u000a is distinct from the attitude in Huntington

S. R. Riedijk; M. F. N. Niermeijer; D. Dooijes; A. Tibben

2009-01-01

192

CTP:phosphocholine cytidylyltransferase ? (CCT?) and lamins alter nuclear membrane structure without affecting phosphatidylcholine synthesis.  

PubMed

CTP:phosphocholine cytidylyltransferase ? (CCT?) is a nuclear enzyme that catalyzes the rate-limiting step in the CDP-choline pathway for phosphatidylcholine (PC) synthesis. Lipid activation of CCT? results in its translocation to the nuclear envelope and expansion of an intranuclear membrane network termed the nucleoplasmic reticulum (NR) by a mechanism involving membrane deformation. Nuclear lamins are also required for stability and proliferation of the NR, but whether this unique structure, or the nuclear lamina in general, is required for PC synthesis is not known. To examine this relationship, the nuclear lamina was depleted by RNAi or disrupted by expression of the Hutchinson-Gilford progeria syndrome (HGPS) mutant lamin A (progerin), and the effect on CCT? and choline metabolism was analyzed. siRNA-mediated silencing of lamin A/C or lamin B1 in CHO cells to diminish the NR had no effect on PC synthesis, while double knockdown non-specifically inhibited the pathway. Confirming this minor role in PC synthesis, only 10% of transiently overexpressed choline/ethanolamine phosphotransferase was detected in the NR. In CHO cells, CCT? was nucleoplasmic and co-localized with GFP-progerin in nuclear folds and invaginations; however, HGPS fibroblasts displayed an abnormal distribution of CCT? in the cytoplasm and nuclear envelope that was accompanied by a 2-fold reduction in PC synthesis. In spite of its altered localization, choline-labeling experiments showed that CCT activity was unaffected, and inhibition of PC synthesis was traced to reduced activity of a hemicholinium-sensitive choline transporter. We conclude that CCT? and lamins specifically cooperate to form the NR, but the overall structure of the nuclear envelope has a minimal impact on CCT activity and PC synthesis. PMID:21504799

Gehrig, Karsten; Ridgway, Neale D

2011-04-09

193

Altering the Ad5 Packaging Domain Affects the Maturation of the Ad Particles  

PubMed Central

We have previously described a new family of mutant adenoviruses carrying different combinations of attB/attP sequences from bacteriophage PhiC31 flanking the Ad5 packaging domain. These novel helper viruses have a significantly delayed viral life cycle and a severe packaging impairment, regardless of the presence of PhiC31 recombinase. Their infectious viral titers are significantly lower (100–1000 fold) than those of control adenovirus at 36 hours post-infection, but allow for efficient packaging of helper-dependent adenovirus. In the present work, we have analyzed which steps of the adenovirus life cycle are altered in attB-helper adenoviruses and investigated whether these viruses can provide the necessary viral proteins in trans. The entry of attB-adenoviral genomes into the cell nucleus early at early timepoints post-infection was not impaired and viral protein expression levels were found to be similar to those of control adenovirus. However, electron microscopy and capsid protein composition analyses revealed that attB-adenoviruses remain at an intermediate state of maturation 36 hours post-infection in comparison to control adenovirus which were fully mature and infective at this time point. Therefore, an additional 20–24 hours were found to be required for the appearance of mature attB-adenovirus. Interestingly, attB-adenovirus assembly and infectivity was restored by inserting a second packaging signal close to the right-end ITR, thus discarding the possibility that the attB-adenovirus genome was retained in a nuclear compartment deleterious for virus assembly. The present study may have substantive implications for helper-dependent adenovirus technology since helper attB-adenovirus allows for preferential packaging of helper-dependent adenovirus genomes.

Alba, Raul; Cots, Dan; Ostapchuk, Philomena; Bosch, Assumpcio; Hearing, Patrick; Chillon, Miguel

2011-01-01

194

Atmospheric deposition may affect northern hardwood forest composition by altering soil nutrient supply.  

PubMed

In the northeastern United States, the input of reactive nitrogen (N) via atmospheric deposition has increased rapidly since the onset of the industrial revolution. During the same period of time, acid precipitation and forest harvest have removed substantial quantities of base cations from soil. Because of the dominance of base-poor soils and the low rates of atmospheric base cation deposition, soils throughout the northeastern United States may be increasingly rich in N but poor in calcium (Ca). We studied the consequences of a change in soil N and Ca availability on forest composition by transplanting seedlings of four tree species into replicate plots in the understory and in canopy gaps amended with N and Ca in factorial combination. In this paper, we report on the growth and survivorship of seedlings over a four-year period. Relative to control plots, fertilization with N increased red maple growth by an average of 39% whereas fertilization with Ca decreased survivorship in the understory by 41%. In sugar maple, fertilization with Ca increased growth by 232% and 46% in the forest understory and in canopy gaps, respectively, and significantly increased high light survivorship. Fertilization with N decreased white pine survivorship by 69% in the understory whereas high Ca availability significantly increased survivorship. Fertilization with N or Ca alone reduced red oak growth but had no effect on survivorship. The results of this study suggest that historical losses of soil Ca and the continuing effects of atmospheric-N deposition on N availability are likely to alter the composition of northeastern North American forests because of the positive effects of N enrichment on the growth of red maple and the negative effects of Ca loss on the growth and survivorship of sugar maple and white pine. PMID:17974332

Zaccherio, Meredith T; Finzi, Adrien C

2007-10-01

195

Electrophysiological Evidence that Ethanol Alters Function of Medial Septal Area Without Affecting Lateral Septal Function1  

PubMed Central

Evidence is provided in this manuscript that ethanol acts directly on neurons in the medial septal area (MSA). Initially, the electrophysiological characteristics of MSA neurons in freely moving rats were characterized and found similar to that observed in rats anesthetized with urethane, but not chloral hydrate. Therefore, urethane was used to evaluate the effects of ethanol in anesthetized rats. The conclusion that ethanol influences neural function in the MSA is based on electrophysiological data that ethanol (0.75–3.0 g/kg i.p.) suppresses neural firing of medial septal cells in urethane-anesthetized as well as in unanesthetized rats in a dose-related fashion. Concurrent with the suppression of firing rate, the rhythmic bursting pattern of activity of MSA neurons is disrupted by ethanol. The changes observed in the MSA could not be attributed to an indirect action of ethanol on afferents from the lateral septum to the MSA, because ethanol did not alter neural activity of cells in the lateral septum. These data indicate that ethanol does not have a common action on all neurons. Neural activity in the MSA recovered from the acute action of ethanol at a time when blood ethanol levels were near maximal, indicating an acute tolerance to this effect of ethanol. The time course of change in neural activity in the MSA was highly correlated with the time course of a measure of behavioral sedation, but not the hypothermia produced by ethanol. Thus, the work in this manuscript supports the view that ethanol has selective actions on MSA neurons in the rat septal area and that these actions may influence the behavioral sedation induced by ethanol.

GIVENS, BENNET S.; BREESE, GEORGE R.

2010-01-01

196

Hand grip strength: A phenotype suitable for identifying genetic variants affecting mid- and late-life physical functioning  

Microsoft Academic Search

Physical functioning late in life has been shown to be affected by genetic factors. Only a few genetic variants have been suggested to be associated with physical functioning, and this only in selected populations (e.g., young healthy males and elite athletes). Declining physical functioning late in life is a major problem in terms of prevalence, morbidity, functional limitations, and quality

Henrik Frederiksen; David Gaist; Hans Christian Petersen; Jacob Hjelmborg; Matt McGue; James W. Vaupel; Kaare Christensen

2002-01-01

197

Molecular genetic alterations in hamartomatous polyps and carcinomas of patients with Peutz-Jeghers syndrome  

PubMed Central

Aim—To investigate whether mutations in the STK11/LKB1 gene and genes implicated in the colorectal adenoma–carcinoma sequence are involved in Peutz-Jeghers syndrome (PJS) related tumorigenesis. Methods—Thirty nine polyps and five carcinomas from 17 patients (from 13 families) with PJS were analysed for loss of heterozygosity (LOH) at 19p13.3 (STK11/LKB1 gene locus), 5q21 (APC gene locus), 18q21–22 (Smad4 and Smad2 gene locus), and 17p13 (p53 gene locus), and evaluated for immunohistochemical staining of p53. In addition, mutational analysis of K-ras codon 12, APC, and p53 and immunohistochemistry for Smad4 expression were performed on all carcinomas. Results—LOH at 19p was seen in 15 of the 39 polyps and in all carcinomas (n = 5). Interestingly, six of the seven polyps from patients with cancer had LOH, compared with nine of the 31 polyps from the remaining patients (p = 0.01). In one polyp from a patient without a germline STK11/LKB1 mutation, no LOH at 19p or at three alternative PJS candidate loci (19q, 6p, and 6q) was found. No LOH at 5q was observed. However, mutational analysis revealed an APC mutation in four of the five carcinomas. LOH at 17p was not seen in polyps or carcinomas; immunohistochemistry showed expression of p53 in one carcinoma and focal expression in three polyps. At subsequent sequence analysis, no p53 mutation was found. One carcinoma had an activating K-ras codon 12 mutation and another carcinoma showed 18q LOH; however, no loss of Smad4 expression was seen. Conclusions—These results provide further evidence that STK11/LKB1 acts as a tumour suppressor gene, and may be involved in the early stages of PJS tumorigenesis. Further research is needed to see whether LOH in PJS polyps could be used as a biomarker to predict cancer. Differences in molecular genetic alterations noted between the adenoma–carcinoma sequence and PJS related tumours suggest the presence of a distinct pathway of carcinogenesis. Key Words: Peutz-Jeghers syndrome • carcinogenesis • STK11/LKB1 • hamartoma

Entius, M; Keller, J; Westerman, A; van Rees, B P; van Velthuysen, M-L F; de Goeij, A F P M; Wilson, J; Giardiello, F; Offerhaus, G

2001-01-01

198

Historical and anthropogenic factors affecting the population genetic structure of Ontario's inland lake populations of Walleye (Sander vitreus).  

PubMed

Populations existing in formerly glaciated areas often display composite historical and contemporary patterns of genetic structure. For Canadian freshwater fishes, population genetic structure is largely reflective of dispersal from glacial refugia and isolation within drainage basins across a range of scales. Enhancement of sport fisheries via hatchery stocking programs and other means has the potential to alter signatures of natural evolutionary processes. Using 11 microsatellite loci genotyped from 2182 individuals, we analyzed the genetic structure of 46 inland lake walleye (Sander vitreus) populations spanning five major drainage basins within the province of Ontario, Canada. Population genetic analyses coupled with genotype assignment allowed us to: 1) characterize broad- and fine-scale genetic structure among Ontario walleye populations; and 2) determine if the observed population divergence is primarily due to natural or historical processes, or recent anthropogenic events. The partitioning of genetic variation revealed higher genetic divergence among lakes than among drainage basins or proposed ancestries-indicative of relatively high isolation among lakes, study-wide. Walleye genotypes were clustered into three major groups, likely reflective of Missourian, Mississippian, and Atlantic glacial refugial ancestry. Despite detectable genetic signatures indicative of anthropogenic influences, province-wide spatial genetic structure remains consistent with the hypothesis of dispersal from distinct glacial refugia and subsequent isolation of lakes within primary drainage basins. Our results provide a novel example of minimal impacts from fishery enhancement to the broad-scale genetic structure of inland fish populations. PMID:23125407

Walter, Ryan P; Cena, Christopher J; Morgan, George E; Heath, Daniel D

2012-11-01

199

A combination of molecular cytogenetic analyses reveals complex genetic alterations in conventional renal cell carcinoma.  

PubMed

Here we report the complex pattern of genomic imbalances and rearrangements in a panel of 19 renal cell carcinoma cell lines detected with molecular cytogenetic analysis. Consistent heterogeneity in chromosome number was found, and most cell lines showed a near-triploid chromosome complement. Several cell lines showed deletions of the TP53 (alias p53), CDKN2A (alias p16), and VHL genes. Multiplex fluorescence in situ hybridization (M-FISH) analysis revealed chromosome 3 translocated to several other partners chromosomes, as well as breakage events commonly affecting chromosomes 1, 5, 8, 10, and 17. The most common abnormality detected with comparative genomic hybridization (CGH) was deletions of chromosome 3p, with loss of the RASSF1, FHIT, and p44S10 loci frequently involved. CGH gain of 5q showed overrepresentation of the EGR1 and CSF1R genes. Recurrent alterations to chromosome 7 included rearrangement of 7q11 and gains of the EGFR, TIF1, and RFC2 genes. Several lines exhibited rearrangement of 12q11 approximately q14 and overrepresentation of CDK4 and SAS loci. M-FISH revealed several other recurrent translocations, and CGH findings included loss of 9p, 14q, and 18q and gain of 8q, 12, and 20. Further genomic microarray changes included loss of MTAP, IGH@, HTR1B, and SMAD4 (previously MADH4) and gains of MYC and TOP1. An excellent correlation was observed between the genomic array and FISH data, demonstrating that this technique is effective and accurate. The aberrations detected here may reflect important pathways in renal cancer pathogenesis. PMID:15860350

Strefford, Jon C; Stasevich, Irina; Lane, Tim M; Lu, Yong-Jie; Oliver, Tim; Young, Bryan D

2005-05-01

200

Environmental stress alters genetic regulation of novelty seeking in vervet monkeys  

PubMed Central

Considerable attention has been paid to identifying genetic influences and gene–environment interactions that increase vulnerability to environmental stressors, with promising but inconsistent results. A nonhuman primate model is presented here that allows assessment of genetic influences in response to a stressful life event for a behavioural trait with relevance for psychopathology. Genetic and environmental influences on free-choice novelty seeking behaviour were assessed in a pedigreed colony of vervet monkeys before and after relocation from a low stress to a higher stress environment. Heritability of novelty seeking scores, and genetic correlations within and between environments were conducted using variance components analysis. The results showed that novelty seeking was markedly inhibited in the higher stress environment, with effects persisting across a 2-year period for adults but not for juveniles. There were significant genetic contributions to novelty seeking scores in each year (h2 = 0.35–0.43), with high genetic correlations within each environment (rhoG > 0.80) and a lower genetic correlation (rhoG = 0.35, non-significant) between environments. There were also significant genetic contributions to individual change scores from before to after the move (h2 = 0.48). These results indicate that genetic regulation of novelty seeking was modified by the level of environmental stress, and they support a role for gene–environment interactions in a behavioural trait with relevance for mental health.

Fairbanks, L A; Bailey, J N; Breidenthal, S E; Laudenslager, M L; Kaplan, J R; Jorgensen, M J

2011-01-01

201

A genetic screen for zygotic embryonic lethal mutations affecting cuticular morphology in the wasp Nasonia vitripennis.  

PubMed Central

We have screened for zygotic embryonic lethal mutations affecting cuticular morphology in Nasonia vitripennis (Hymenoptera; Chalcidoidea). Our broad goal was to investigate the use of Nasonia for genetically surveying conservation and change in regulatory gene systems, as a means to understand the diversity of developmental strategies that have arisen during the course of evolution. Specifically, we aim to compare anteroposterior patterning gene functions in two long germ band insects, Nasonia and Drosophila. In Nasonia, unfertilized eggs develop as haploid males while fertilized eggs develop as diploid females, so the entire genome can be screened for recessive zygotic mutations by examining the progeny of F1 females. We describe 74 of >100 lines with embryonic cuticular mutant phenotypes, including representatives of coordinate, gap, pair-rule, segment polarity, homeotic, and Polycomb group functions, as well as mutants with novel phenotypes not directly comparable to those of known Drosophila genes. We conclude that Nasonia is a tractable experimental organism for comparative developmental genetic study. The mutants isolated here have begun to outline the extent of conservation and change in the genetic programs controlling embryonic patterning in Nasonia and Drosophila.

Pultz, M A; Zimmerman, K K; Alto, N M; Kaeberlein, M; Lange, S K; Pitt, J N; Reeves, N L; Zehrung, D L

2000-01-01

202

Human erythroid cells are affected by aluminium. Alteration of membrane band 3 protein.  

PubMed

There is evidence that anaemia is associated with aluminium (Al). We have already reported on the sensitivity to Al, showed by erythroid cell populations of animals chronically exposed to the metal. In order to investigate whether Al could also affect human cells, experiments were carried out both on immature and mature human erythroid cells. Erythroid progenitors (CFU-E, colony-forming units-erythroid) concentrated from human peripheral blood were cultured in an Al-rich medium under erythropoietin stimulation and their development analysed. Human peripheral erythrocytes were aged in the presence of Al. Cells were examined using scanning electron microscopy, and membrane proteins analysed by polyacrylamide gel electrophoresis with sodium dodecyl sulphate and immunoblotting. The development of the Al-treated progenitors was 8750/6600-9200 CFU-E/10(6) cells, a significantly lower median value (P<0.05) than that showed by non-treated cells (12300/11200-20700 CFU-E/10(6) cells). Erythrocyte morphological changes were induced by Al during the in vitro ageing. The cells lost their typical biconcave shape, turning into acanthocytes and stomatocytes. Simultaneously, an increased membrane protein breakdown compatible with band 3 degradation was detected. Besides, Al was found within the cells and attached to the membrane. The present in vitro results suggest that Al may disturb human erythropoiesis through combined effects on mature erythrocytes and cellular metabolism in late erythroid progenitors. PMID:11779564

Vittori, Daniela; Garbossa, Graciela; Lafourcade, Carlos; Pérez, Gladys; Nesse, Alcira

2002-02-01

203

Mutant huntingtin affects endocytosis in striatal cells by altering the binding of AP-2 to membranes.  

PubMed

Clathrin-mediated endocytosis plays an important role in the maintenance of neuronal integrity in the synaptic terminals. Here we studied the effect of anomalous polyglutamine expansion in huntingtin on the interaction of coat proteins with membranes, in areas of mouse brain or in cultured striatal cells. We observed that this anomaly induces a redistribution of AP-2, but not other coat proteins, from the membrane to the cytosol in the striatum, and in the cultured striatal cells. It was also noted that huntingtin associates with AP-2, and that this association decreases due to the mutation in huntingtin. This decreased receptor-mediated endocytosis, measured by the internalization of transferrin in the mutated cells. It was also confirmed that huntingtin mutation made the cells more vulnerable to the action of quinolinic acid, with an increasing degradation of the AP-2 alpha subunits. On the basis of these results, we conclude that abnormal polyglutamine expansion in huntingtin affects clathrin-mediated endocytosis, and may be one of the pathogenic mechanisms of neurodegeneration. PMID:23219902

Borgonovo, Janina E; Troncoso, Mariana; Lucas, José J; Sosa, Miguel A

2012-12-05

204

Cultivation and Comprehension: How Genetic Modification Irreversibly Alters the Human Engagement with Nature  

Microsoft Academic Search

Genetic engineering is placed in the context of a history of transformations of the relations between 'cultivated nature' and 'naturally occurring nature'. It is argued that genetic modification is a bio-socio-economic process, producing new diversity within cultivated nature. Viewing bio- science and technology as 'socially embedded', it argues that different trajectories of their development have both the much trumpeted negative

Mark Harvey

1999-01-01

205

Lung adenocarcinoma of never smokers and smokers harbor differential regions of genetic alteration and exhibit different levels of genomic instability.  

PubMed

Recent evidence suggests that the observed clinical distinctions between lung tumors in smokers and never smokers (NS) extend beyond specific gene mutations, such as EGFR, EML4-ALK, and KRAS, some of which have been translated into targeted therapies. However, the molecular alterations identified thus far cannot explain all of the clinical and biological disparities observed in lung tumors of NS and smokers. To this end, we performed an unbiased genome-wide, comparative study to identify novel genomic aberrations that differ between smokers and NS. High resolution whole genome DNA copy number profiling of 69 lung adenocarcinomas from smokers (n?=?39) and NS (n?=?30) revealed both global and regional disparities in the tumor genomes of these two groups. We found that NS lung tumors had a greater proportion of their genomes altered than those of smokers. Moreover, copy number gains on chromosomes 5q, 7p, and 16p occurred more frequently in NS. We validated our findings in two independently generated public datasets. Our findings provide a novel line of evidence distinguishing genetic differences between smoker and NS lung tumors, namely, that the extent of segmental genomic alterations is greater in NS tumors. Collectively, our findings provide evidence that these lung tumors are globally and genetically different, which implies they are likely driven by distinct molecular mechanisms. PMID:22412972

Thu, Kelsie L; Vucic, Emily A; Chari, Raj; Zhang, Wei; Lockwood, William W; English, John C; Fu, Rong; Wang, Pei; Feng, Ziding; MacAulay, Calum E; Gazdar, Adi F; Lam, Stephen; Lam, Wan L

2012-03-07

206

Genetic analysis of an Indian family with members affected with Waardenburg syndrome and Duchenne muscular dystrophy  

PubMed Central

Purpose Waardenburg syndrome (WS) is characterized by sensorineural hearing loss and pigmentation defects of the eye, skin, and hair. It is caused by mutations in one of the following genes: PAX3 (paired box 3), MITF (microphthalmia-associated transcription factor), EDNRB (endothelin receptor type B), EDN3 (endothelin 3), SNAI2 (snail homolog 2, Drosophila) and SOX10 (SRY-box containing gene 10). Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutations in the DMD gene. The purpose of this study was to identify the genetic causes of WS and DMD in an Indian family with two patients: one affected with WS and DMD, and another one affected with only WS. Methods Blood samples were collected from individuals for genomic DNA isolation. To determine the linkage of this family to the eight known WS loci, microsatellite markers were selected from the candidate regions and used to genotype the family. Exon-specific intronic primers for EDN3 were used to amplify and sequence DNA samples from affected individuals to detect mutations. A mutation in DMD was identified by multiplex PCR and multiplex ligation-dependent probe amplification method using exon-specific probes. Results Pedigree analysis suggested segregation of WS as an autosomal recessive trait in the family. Haplotype analysis suggested linkage of the family to the WS4B (EDN3) locus. DNA sequencing identified a novel missense mutation p.T98M in EDN3. A deletion mutation was identified in DMD. Conclusions This study reports a novel missense mutation in EDN3 and a deletion mutation in DMD in the same Indian family. The present study will be helpful in genetic diagnosis of this family and increases the mutation spectrum of EDN3.

Kapoor, Saketh; Bindu, Parayil Sankaran; Taly, Arun B.; Sinha, Sanjib; Gayathri, Narayanappa; Rani, S. Vasantha; Chandak, Giriraj Ratan

2012-01-01

207

Potential Vulnerability Markers within the Affective Domain in Subjects at Genetic and Clinical High Risk for Schizophrenia  

Microsoft Academic Search

Background: Relative to ample high-risk studies on neurocognitive function, only a few high-risk studies have examined affective functioning components as possible vulnerability markers. In this study, we comprehensively assessed baseline affective functioning in subjects at clinical high risk (CHR) and genetic high risk (GHR) for schizophrenia, and healthy controls (HC), and compared the results to elucidate possible vulnerability markers in

Seung Jae Lee; So Young Yoo; Do-Hyung Kang; Kyung Jin Lee; Tae Hyun Ha; Whee Wee; Ae-Ra Lee; Nam Sick Kim; Jun Soo Kwon

2008-01-01

208

Polybrominated diphenyl ethers affect the reproduction and development, and alter the sex ratio of zebrafish (Danio rerio).  

PubMed

Polybrominated diphenyl ethers (PBDEs) have been commonly used as flame retardants and now become ubiquitous in the global environment. Using zebrafish as a model, we tested the hypothesis that PBDEs may affect the reproduction and development of fish. Zebrafish were exposed to environmentally relevant concentrations of DE-71 (a congener of PBDE commonly found in the environment) throughout their whole life cycle, and the effects of DE-71 on gonadal development, gamete quality, fertilization success, hatching success, embryonic development and sex ratio were investigated. Despite gonadal development was enhanced, reductions in spawning, fertilization success, hatching success and larval survival rate were evident, while significant increases in malformation and percentage of male were also observed in the F1 generation. Our laboratory results suggest that PBDEs may pose a risk to reproductive success and alter the sex ratio of fish in environments highly contaminated with PBDEs. PMID:23906559

Han, X B; Yuen, Karen W Y; Wu, Rudolf S S

2013-07-31

209

Micronucleus test and observation of nuclear alterations in erythrocytes of Nile tilapia exposed to waters affected by refinery effluent.  

PubMed

Micronuclei and nuclear alterations tests were performed on erythrocytes of Oreochromis niloticus (Perciformes, Cichlidae) in order to evaluate the water quality from Paraíba do Sul river, in an area affected by effluents from an oil shale processing plant, located in the city of São José dos Campos, Brazil-SP. Water samples were collected on 2004 May and August (dry season) and on 2004 November and 2005 January (rain season), in three distinct sites, comprising 12 samples. It was possible to detect substances of clastogenic and/or aneugenic potential, as well as cytotoxic substances, chiefly at the point corresponding to the drainage of oil shale plant wastes along the river. The highest incidence of micronuclei and nuclear alterations was detected during May and August, whereas the results obtained in November and January were insignificant. This work shows that the effluent treatment provided by the oil shale plant was not fully efficient to minimize the effect of cytotoxic and mutagenic substances in the test organism surveyed. PMID:16678473

da Silva Souza, Tatiana; Fontanetti, Carmem S

2006-05-04

210

Genetic mapping of quantitative trait loci affecting growth and carcass traits in F2 intercross chickens.  

PubMed

We constructed a chicken F(2) resource population to facilitate the genetic improvement of economically important traits, particularly growth and carcass traits. An F(2) population comprising 240 chickens obtained by crossing a Shamo (lean, lightweight Japanese native breed) male and White Plymouth Rock breed (fat, heavyweight broiler) females was measured for BW, carcass weight (CW), abdominal fat weight (AFW), breast muscle weight (BMW), and thigh muscle weight (TMW) and was used for genome-wide linkage and QTL analysis, using a total of 240 microsatellite markers. A total of 14 QTL were detected at a 5% chromosome-wide level, and 7 QTL were significant at a 5% experiment-wide level for the traits evaluated in the F(2) population. For growth traits, significant and suggestive QTL affecting BW (measured at 6 and 9 wk) and average daily gain were identified on similar regions of chromosomes 1 and 3. For carcass traits, the QTL effects on CW were detected on chromosomes 1 and 3, with the greatest F-ratio of 15.0 being obtained for CW on chromosome 3. Quantitative trait loci positions affecting BMW and TMW were not detected at the same loci as those detected for BMW percentage of CW and TMW percentage of CW. For AFW, QTL positions were detected at the same loci as those detected for AFW percentage of CW. The present study identified significant QTL affecting BW, CW, and AFW. PMID:19211515

Uemoto, Y; Sato, S; Odawara, S; Nokata, H; Oyamada, Y; Taguchi, Y; Yanai, S; Sasaki, O; Takahashi, H; Nirasawa, K; Kobayashi, E

2009-03-01

211

Tg.AC Genetically Altered Mouse: Assay Working Group Overview of Available Data  

Microsoft Academic Search

In aGovernment\\/Industry\\/Academicpartnershiptoevaluatealternativeapproachestocarcinogenicity testing,21pharmaceuticalagentsrepresenting avariety ofchemical and pharmacological classes and possessing known human and or rodent carcinogenicpotential wereselected forstudy in several rodent models. The studies from this partnership project, coordinated by the International Life Sciences Institute, provide additional data to better understand themodels' limitationsand sensitivity in identifying carcinogens. Theresultsof these alternativemodelstudieswerereviewed by members ofAssayWorkingGroups (AWG)composedofscientistsfromgovernmentand industrywith expertiseintoxicology,genetics,statistics,andpathology. The Tg.AC genetically manipulated

WILLIAM C. EASTIN; JOHN H. MENNEAR; RAY W. TENNANT; RAY E. STOLL; DAN G. BRANSTETTER; JOHN R. BUCHER; Bruce McCullough; ROBERT L. BINDER; JUDSON W. SPALDING; JOEL F. MAHLER

2001-01-01

212

Stem and progenitor cells in myelodysplastic syndromes show aberrant stage-specific expansion and harbor genetic and epigenetic alterations  

PubMed Central

Even though hematopoietic stem cell (HSC) dysfunction is presumed in myelodysplastic syndrome (MDS), the exact nature of quantitative and qualitative alterations is unknown. We conducted a study of phenotypic and molecular alterations in highly fractionated stem and progenitor populations in a variety of MDS subtypes. We observed an expansion of the phenotypically primitive long-term HSCs (lineage?/CD34+/CD38?/CD90+) in MDS, which was most pronounced in higher-risk cases. These MDS HSCs demonstrated dysplastic clonogenic activity. Examination of progenitors revealed that lower-risk MDS is characterized by expansion of phenotypic common myeloid progenitors, whereas higher-risk cases revealed expansion of granulocyte-monocyte progenitors. Genome-wide analysis of sorted MDS HSCs revealed widespread methylomic and transcriptomic alterations. STAT3 was an aberrantly hypomethylated and overexpressed target that was validated in an independent cohort and found to be functionally relevant in MDS HSCs. FISH analysis demonstrated that a very high percentage of MDS HSC (92% ± 4%) carry cytogenetic abnormalities. Longitudinal analysis in a patient treated with 5-azacytidine revealed that karyotypically abnormal HSCs persist even during complete morphologic remission and that expansion of clonotypic HSCs precedes clinical relapse. This study demonstrates that stem and progenitor cells in MDS are characterized by stage-specific expansions and contain epigenetic and genetic alterations.

Will, Britta; Zhou, Li; Vogler, Thomas O.; Ben-Neriah, Susanna; Schinke, Carolina; Tamari, Roni; Yu, Yiting; Bhagat, Tushar D.; Bhattacharyya, Sanchari; Barreyro, Laura; Heuck, Christoph; Mo, Yonkai; Parekh, Samir; McMahon, Christine; Pellagatti, Andrea; Boultwood, Jacqueline; Montagna, Cristina; Silverman, Lewis; Maciejewski, Jaroslaw; Greally, John M.; Ye, B. Hilda; List, Alan F.; Steidl, Christian

2012-01-01

213

Stem and progenitor cells in myelodysplastic syndromes show aberrant stage-specific expansion and harbor genetic and epigenetic alterations.  

PubMed

Even though hematopoietic stem cell (HSC) dysfunction is presumed in myelodysplastic syndrome (MDS), the exact nature of quantitative and qualitative alterations is unknown. We conducted a study of phenotypic and molecular alterations in highly fractionated stem and progenitor populations in a variety of MDS subtypes. We observed an expansion of the phenotypically primitive long-term HSCs (lineage(-)/CD34(+)/CD38(-)/CD90(+)) in MDS, which was most pronounced in higher-risk cases. These MDS HSCs demonstrated dysplastic clonogenic activity. Examination of progenitors revealed that lower-risk MDS is characterized by expansion of phenotypic common myeloid progenitors, whereas higher-risk cases revealed expansion of granulocyte-monocyte progenitors. Genome-wide analysis of sorted MDS HSCs revealed widespread methylomic and transcriptomic alterations. STAT3 was an aberrantly hypomethylated and overexpressed target that was validated in an independent cohort and found to be functionally relevant in MDS HSCs. FISH analysis demonstrated that a very high percentage of MDS HSC (92% ± 4%) carry cytogenetic abnormalities. Longitudinal analysis in a patient treated with 5-azacytidine revealed that karyotypically abnormal HSCs persist even during complete morphologic remission and that expansion of clonotypic HSCs precedes clinical relapse. This study demonstrates that stem and progenitor cells in MDS are characterized by stage-specific expansions and contain epigenetic and genetic alterations. PMID:22753872

Will, Britta; Zhou, Li; Vogler, Thomas O; Ben-Neriah, Susanna; Schinke, Carolina; Tamari, Roni; Yu, Yiting; Bhagat, Tushar D; Bhattacharyya, Sanchari; Barreyro, Laura; Heuck, Christoph; Mo, Yonkai; Parekh, Samir; McMahon, Christine; Pellagatti, Andrea; Boultwood, Jacqueline; Montagna, Cristina; Silverman, Lewis; Maciejewski, Jaroslaw; Greally, John M; Ye, B Hilda; List, Alan F; Steidl, Christian; Steidl, Ulrich; Verma, Amit

2012-07-02

214

Genetic Organization of the Region around UNC-15 (I), a Gene Affecting Paramyosin in CAENORHABDITIS ELEGANS  

PubMed Central

In the nematode Caenorhabditis elegans mutants in the gene unc-15 (I) affect the muscle protein paramyosin (Waterston, Fishpool and Brenner 1977). We have characterized 20 ethyl methanesulfonate-induced mutations in essential genes closely linked to unc-15. These lethals defined 16 new complementation groups. In the 0.65 map-unit interval around unc-15 defined by dpy-14 and unc-56, seven newly identified genes have been mapped relative to five existing genes. At present, the average distance between genes in this region is approximately 0.05 map units. Two genes, unc-15 and unc-13, are only 0.025 map units apart. Partial fine-structure maps of alleles of these two genes have been constructed. This analysis of unc-15 and genes adjacent to it is the first in a series of genetic and biochemical studies directed towards understanding the control of unc-15 expression.

Rose, A. M.; Baillie, D. L.

1980-01-01

215

Genetic and biological characterization of a densovirus isolate that affects dengue virus infection.  

PubMed

Brevidensoviruses have an encapsidated, single-stranded DNA genome that predominantly has a negative polarity. In recent years, they have received particular attention due to their potential role in the biological control of pathogenic arboviruses and to their unnoticed presence in cell cultures as contaminants. In addition, brevidensoviruses may also be useful as viral vectors. This study describes the first genetic and biological characterization of a mosquito densovirus that was isolated in Brazil; moreover, we examined the phylogenetic relationship between this isolate and the other brevidensoviruses. We further demonstrate that this densovirus has the potential to be used to biologically control dengue virus (DENV) infection with in vitro co-infection experiments. The present study provides evidence that this densovirus isolate is a fast-spreading virus that affects cell growth and DENV infection. PMID:21655815

Mosimann, Ana Luiza Pamplona; Bordignon, Juliano; Mazzarotto, Giovanny Camacho Antevêre; Motta, Maria Cristina M; Hoffmann, Federico; Santos, Claudia Nunes Duarte Dos

2011-05-01

216

Clinical, genetic and immunologic analysis of a family affected by ozena.  

PubMed

Primary atrophic rhinitis is a chronic inflammation of the nasal mucosa characterized by atrophy of the mucous and bony tissue of the turbinates and by a thick, dense secretion, which quickly forms a characteristically fetid-smelling, greenish crust. We report the results of the clinical, genetic and immunologic investigations performed on eight subjects (three with ozena and five asymptomatic), members of the same familial group. The presence of the disease in the family fits well with dominant inheritance. All the culture specimens from the patients affected by ozena were positive for Klebsiella ozaenae, and one of them was also positive for Pseudomonas aeruginosa. All the three patients with ozena and two of the five apparently unaffected family members were positive for antinuclear antibodies. Immunoblotting showed a reactivity to a 50-kD protein, which was not identified by the common, recognized nuclear autoantigens. This was present in one of the three patients and three of the five other family members. Positivity for IgG-class anticardiolipins was correlated with disease manifestation in that it was found in two of the three patients and only in one of the five asymptomatic family members. The hypothesis of a genetic factor that could drive the chronicity of the inflammatory pattern of a pre-existing infectious nasal disease is suggested. PMID:12682843

Medina, Lucia; Benazzo, Marco; Bertino, Giulia; Montecucco, Carlo Maurizio; Danesino, Cesare; Martinetti, Miryam; Mira, Eugenio

2003-03-26

217

Genetic deletion of the EGFR ligand epigen does not affect mouse embryonic development and tissue homeostasis.  

PubMed

The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor with manifold functions during development, tissue homeostasis and disease. EGFR activation, the formation of homodimers or heterodimers (with the related ERBB2-4 receptors) and downstream signaling is initiated by the binding of a family of structurally related growth factors, the EGFR ligands. Genetic deletion experiments clarified the biological function of all family members except for the last characterized ligand, epigen. We employed gene targeting in mouse embryonic stem cells to generate mice lacking epigen expression. Loss of epigen did not affect mouse development, fertility, or organ physiology. Quantitative RT-PCR analysis revealed increased expression of betacellulin and EGF in a few organs of epigen-deficient mice, suggesting a functional compensation by these ligands. In conclusion, we completed the genetic analysis of EGFR ligands and show that epigen has non-essential functions or functions that can be compensated by other EGFR ligands during growth and tissue homeostasis. PMID:23142483

Dahlhoff, Maik; Schäfer, Matthias; Wolf, Eckhard; Schneider, Marlon R

2012-11-06

218

Alterations in Seed Development Gene Expression Affect Size and Oil Content of Arabidopsis Seeds1[C][W][OPEN  

PubMed Central

Seed endosperm development in Arabidopsis (Arabidopsis thaliana) is under control of the polycomb group complex, which includes Fertilization Independent Endosperm (FIE). The polycomb group complex regulates downstream factors, e.g. Pheres1 (PHE1), by genomic imprinting. In heterozygous fie mutants, an endosperm develops in ovules carrying a maternal fie allele without fertilization, finally leading to abortion. Another endosperm development pathway depends on MINISEED3 (a WRKY10 transcription factor) and HAIKU2 (a leucine-rich repeat kinase). While the role of seed development genes in the embryo and endosperm establishment has been studied in detail, their impact on metabolism and oil accumulation remained unclear. Analysis of oil, protein, and sucrose accumulation in mutants and overexpression plants of the four seed development genes revealed that (1) seeds carrying a maternal fie allele accumulate low oil with an altered composition of triacylglycerol molecular species; (2) homozygous mutant seeds of phe1, mini3, and iku2, which are smaller, accumulate less oil and slightly less protein, and starch, which accumulates early during seed development, remains elevated in mutant seeds; (3) embryo-specific overexpression of FIE, PHE1, and MINI3 has no influence on seed size and weight, nor on oil, protein, or sucrose content; and (4) overexpression of IKU2 results in seeds with increased size and weight, and oil content of overexpressed IKU2 seeds is increased by 35%. Thus, IKU2 overexpression represents a novel strategy for the genetic manipulation of the oil content in seeds.

Fatihi, Abdelhak; Zbierzak, Anna Maria; Dormann, Peter

2013-01-01

219

Identification of genetic factors altering the SOS induction of DNA damage-inducible yebG gene in Escherichia coli  

Microsoft Academic Search

The yebG gene of Escherichia coli is a novel SOS regulon gene, but details of its regulation mechanism and biological function are not yet known. To characterize the regulation of yebG gene as a SOS gene, we identified the genetic factors affecting the SOS induction of yebG gene using yebG-lacZ operon fusion plasmid. We found that the SOS induction of

Tae Jeong Oh; In Gyu Kim

1999-01-01

220

A genetic study of the anesthetic response: mutants of Drosophila melanogaster altered in sensitivity to halothane.  

PubMed Central

In an attempt to identify genes that control or encode the targets of general anesthetics, we have chemically mutagenized fruit flies and selected four lines that show an abnormal response to the volatile anesthetic halothane. Specifically, about 2-fold higher concentrations of halothane are required to induce the loss of motor control in the mutant flies. Fine mapping of two isolates indicates that they alter a previously uncharacterized gene of Drosophila. In the absence of anesthetics, these mutants display alterations of behavior that imply changes in the adult and the larval neuromuscular system. Images

Krishnan, K S; Nash, H A

1990-01-01

221

Is the Genetic Landscape of the Deep Subsurface Biosphere Affected by Viruses?  

PubMed Central

Viruses are powerful manipulators of microbial diversity, biogeochemistry, and evolution in the marine environment. Viruses can directly influence the genetic capabilities and the fitness of their hosts through the use of fitness factors and through horizontal gene transfer. However, the impact of viruses on microbial ecology and evolution is often overlooked in studies of the deep subsurface biosphere. Subsurface habitats connected to hydrothermal vent systems are characterized by constant fluid flux, dynamic environmental variability, and high microbial diversity. In such conditions, high adaptability would be an evolutionary asset, and the potential for frequent host–virus interactions would be high, increasing the likelihood that cellular hosts could acquire novel functions. Here, we review evidence supporting this hypothesis, including data indicating that microbial communities in subsurface hydrothermal fluids are exposed to a high rate of viral infection, as well as viral metagenomic data suggesting that the vent viral assemblage is particularly enriched in genes that facilitate horizontal gene transfer and host adaptability. Therefore, viruses are likely to play a crucial role in facilitating adaptability to the extreme conditions of these regions of the deep subsurface biosphere. We also discuss how these results might apply to other regions of the deep subsurface, where the nature of virus–host interactions would be altered, but possibly no less important, compared to more energetic hydrothermal systems.

Anderson, Rika E.; Brazelton, William J.; Baross, John A.

2011-01-01

222

Genetic variation in human NPY expression affects stress response and emotion  

PubMed Central

Understanding inter-individual differences in stress response requires the explanation of genetic influences at multiple phenotypic levels, including complex behaviours and the metabolic responses of brain regions to emotional stimuli. Neuropeptide Y (NPY) is anxiolytic1,2 and its release is induced by stress3. NPY is abundantly expressed in regions of the limbic system that are implicated in arousal and in the assignment of emotional valences to stimuli and memories4–6. Here we show that haplotype-driven NPY expression predicts brain responses to emotional and stress challenges and also inversely correlates with trait anxiety. NPY haplotypes predicted levels of NPY messenger RNA in postmortem brain and lymphoblasts, and levels of plasma NPY. Lower haplotype-driven NPY expression predicted higher emotion-induced activation of the amygdala, as well as diminished resiliency as assessed by pain/stress-induced activations of endogenous opioid neurotransmission in various brain regions. A single nucleotide polymorphism (SNP rs16147) located in the promoter region alters NPY expression in vitro and seems to account for more than half of the variation in expression in vivo. These convergent findings are consistent with the function of NPY as an anxiolytic peptide and help to explain inter-individual variation in resiliency to stress, a risk factor for many diseases.

Zhou, Zhifeng; Zhu, Guanshan; Hariri, Ahmad R.; Enoch, Mary-Anne; Scott, David; Sinha, Rajita; Virkkunen, Matti; Mash, Deborah C.; Lipsky, Robert H.; Hu, Xian-Zhang; Hodgkinson, Colin A.; Xu, Ke; Buzas, Beata; Yuan, Qiaoping; Shen, Pei-Hong; Ferrell, Robert E.; Manuck, Stephen B.; Brown, Sarah M.; Hauger, Richard L.; Stohler, Christian S.; Zubieta, Jon-Kar; Goldman, David

2009-01-01

223

Genetic variation in human NPY expression affects stress response and emotion.  

PubMed

Understanding inter-individual differences in stress response requires the explanation of genetic influences at multiple phenotypic levels, including complex behaviours and the metabolic responses of brain regions to emotional stimuli. Neuropeptide Y (NPY) is anxiolytic and its release is induced by stress. NPY is abundantly expressed in regions of the limbic system that are implicated in arousal and in the assignment of emotional valences to stimuli and memories. Here we show that haplotype-driven NPY expression predicts brain responses to emotional and stress challenges and also inversely correlates with trait anxiety. NPY haplotypes predicted levels of NPY messenger RNA in post-mortem brain and lymphoblasts, and levels of plasma NPY. Lower haplotype-driven NPY expression predicted higher emotion-induced activation of the amygdala, as well as diminished resiliency as assessed by pain/stress-induced activations of endogenous opioid neurotransmission in various brain regions. A single nucleotide polymorphism (SNP rs16147) located in the promoter region alters NPY expression in vitro and seems to account for more than half of the variation in expression in vivo. These convergent findings are consistent with the function of NPY as an anxiolytic peptide and help to explain inter-individual variation in resiliency to stress, a risk factor for many diseases. PMID:18385673

Zhou, Zhifeng; Zhu, Guanshan; Hariri, Ahmad R; Enoch, Mary-Anne; Scott, David; Sinha, Rajita; Virkkunen, Matti; Mash, Deborah C; Lipsky, Robert H; Hu, Xian-Zhang; Hodgkinson, Colin A; Xu, Ke; Buzas, Beata; Yuan, Qiaoping; Shen, Pei-Hong; Ferrell, Robert E; Manuck, Stephen B; Brown, Sarah M; Hauger, Richard L; Stohler, Christian S; Zubieta, Jon-Kar; Goldman, David

2008-04-02

224

Genetic variation of the serotonin 2a receptor affects hippocampal novelty processing in humans.  

PubMed

Serotonin (5-hydroxytryptamine, 5-HT) is an important neuromodulator in learning and memory processes. A functional genetic polymorphism of the 5-HT 2a receptor (5-HTR2a His452Tyr), which leads to blunted intracellular signaling, has previously been associated with explicit memory performance in several independent cohorts, but the underlying neural mechanisms are thus far unclear. The human hippocampus plays a critical role in memory, particularly in the detection and encoding of novel information. Here we investigated the relationship of 5-HTR2a His452Tyr and hippocampal novelty processing in 41 young, healthy subjects using functional magnetic resonance imaging (fMRI). Participants performed a novelty/familiarity task with complex scene stimuli, which was followed by a delayed recognition memory test 24 hours later. Compared to His homozygotes, Tyr carriers exhibited a diminished hippocampal response to novel stimuli and a higher tendency to judge novel stimuli as familiar during delayed recognition. Across the cohort, the false alarm rate during delayed recognition correlated negatively with the hippocampal novelty response. Our results suggest that previously reported effects of 5-HTR2a on explicit memory performance may, at least in part, be mediated by alterations of hippocampal novelty processing. PMID:21267461

Schott, Björn H; Seidenbecher, Constanze I; Richter, Sylvia; Wüstenberg, Torsten; Debska-Vielhaber, Grazyna; Schubert, Heike; Heinze, Hans-Jochen; Richardson-Klavehn, Alan; Düzel, Emrah

2011-01-18

225

Factors affecting performance of prenatal genetic testing by Israeli Jewish women.  

PubMed

The number of prenatal genetic tests that are being offered to women is constantly increasing. However, there is little national data as to who is performing the tests and the reasons for doing or not doing so. This study evaluated the proportion of Jewish women in Israel who perform the various prenatal genetic tests and the factors affecting the performance of these tests. It was found that 60.9% of the women performed the triple test, 50.8% of women older than 35 years performed amniocentesis, while 63.3 and 24.3% of women performed Tay-Sachs and fragile-X carrier testing respectively. Ninety-six percent of the secular women compared to only 6.7% of the ultrareligious women performed the triple test. It was also found that94.4% of the secular women, 36.4% of the religious, and none of the ultrareligious women older than 35 years performed amniocentesis. In the stepwise regression analysis, being secular, having a higher income, fewer children, and being of Ashkenazi origin remained significant factors in determining performance of Tay-Sachs carrier testing. As regards fragile-X carrier testing, being secular, having fewer than four children, and having a higher income and a supplementary medical insurance remained significant factors. The main reason reported by the women for not performing amniocentesis or the triple test was for religious or moral grounds (53.3 and 67% respectively). The main reason given for not performing Tay-Sachs or fragile-X testing was that they were not referred for the tests (76 and 82% respectively). Consideration should be given to providing first trimester prenatal diagnosis to the ultrareligious group, including state subsidized fragile-X testing and educating the primary care givers about the importance of prenatal genetic testing. The information from the present study is vital for the planning of an equitable prenatal genetic service and provides guidelines for the implementation of such services in other countries. PMID:12838566

Sher, Carron; Romano-Zelekha, Orly; Green, Manfred S; Shohat, Tamy

2003-07-30

226

Genetic alterations in primary osteosarcoma from 54 children and adolescents by targeted allelotyping.  

PubMed

At present, the only recognised prognostic factor for primary osteosarcoma is the histological response to preoperative chemotherapy. Our study was designed to identify new diagnostic markers that could eventually have a prognostic value. A total of 54 patients under 20 years of age with primary osteosarcomas were studied while under treatment by the French Society of Paediatric Oncology OS 94 protocol. Paired normal and biopsy samples were collected. In addition, surgical resection specimens, following preoperative chemotherapy, were obtained in 13 cases. After genomic DNA extraction, an allelotyping analysis targeting microsatellites linked to Rb and p53 genes, and 9p21, 7q31 and 5q21 regions was performed. In all, 94% of the samples at diagnosis showed allelic imbalance and the biopsies were highly rearranged except for the microsatellite targeting 7q31. The same panel was highly informative at surgical resection. Microsatellites investigating Rb, p53 and the 9p21 region were particularly altered without a significant correlation with prognosis. On the other hand, the alteration of the 7q31 locus at diagnosis was significantly correlated with a worse prognosis and a new frequently altered locus, 5q21, was described. In conclusion, this panel allowed us to characterise paediatric osteosarcomas. Correlation of prognosis with the altered 7q31 region could be a useful tool and further studies are required to confirm the importance of 5q21. PMID:12799638

Entz-Werle, N; Schneider, A; Kalifa, C; Voegeli, A-C; Tabone, M-D; Marec-Berard, P; Marcellin, L; Pacquement, H; Terrier, P; Boutard, P; Meyer, N; Gaub, M-P; Lutz, P; Babin, A; Oudet, P

2003-06-16

227

Personality endophenotypes for bipolar affective disorder: a family-based genetic association analysis.  

PubMed

Genetic analyses of complex conditions such as bipolar disorder (BD) may be facilitated by the use of intermediate phenotypes. Various personality traits are overrepresented in people with BD and their unaffected relatives, and may constitute genetically transmitted risk factors or endophenotypes of the illness. In this study, we administered a battery of seven different personality questionnaires comprising 19 subscales to 31 Caucasian BD families (n = 241). Ten of these personality traits showed significant evidence of heritability and were therefore selected as candidate endophenotypes. In addition, a principal components analysis produced two heritable components (negative affect and appetitive drive), which accounted for a considerable proportion of the variance (29% + 12%) and were also used in the analysis. A family-based quantitative association study was carried out using the orthogonal model from the quantitative transmission disequilibrium tests (QTDT) program. Monte Carlo permutations (M = 500), which allow for non-normal data and provide a global P value, corrected for multiple testing, were used to calculate empirical P values for the within-family component of association. The 3' untranslated region repeat polymorphism of the dopamine transporter gene (SLC6A3) was associated with self-directedness (P < 0.0001) and negative affect (P = 0.010). The short allele of the serotonin transporter gene (SLC6A4) promoter polymorphism showed a trend toward association with higher harm avoidance (P = 0.016) and negative affect (P = 0.028). The catechol-o-methyltransferase val158met polymorphism was weakly associated with the personality traits, 'Spirituality' (P = 0.040) and irritable temperament (P = 0.022). Furthermore, the met allele of the brain-derived neurotrophic factor val66met polymorphism was associated with higher hyperthymic temperament scores. We raise the possibility that the 10R allele of the SLC6A3 repeat polymorphism and the short allele of the SLC6A4 promoter variant constitute risk factors for irritable-aggressive and anxious-dysthymic subtypes of BD, respectively. PMID:18826446

Savitz, J; van der Merwe, L; Ramesar, R

2008-09-24

228

Altered Catecholamine Contents in Vascular and Nonvascular Tissues in Genetically Hypertensive Rats  

Microsoft Academic Search

We have measured the catecholamine (CA) contents in hearts, mesenteric vasculature, abdominal aorta, inferior vena cava, vasa deferentia and salivary glands from genetically hypertensive rats (SHR) and normotensive Kyoto-Wistar rats (WKY). We noted differences between the norepinephrine (NE) contents of individual tissues from SHR and WKY rats and have used two different analytical procedures for the measurement of NE to

R. J. Head; L. A. Cassis; R. L. Robinson; D. P. Westfall; R. E. Stitzel

1985-01-01

229

Physical characteristics of genetically-altered wheat related to technological protein separation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wheat protein is a technologically challenging substrate for food and non-food applications because of its compositional diversity and susceptibility to denaturation. Genetic modification could be used to create cultivars capable of producing more uniform or focused and novel protein compositions t...

230

Genetic variations alter physiological responses following heat stress in 2 strains of laying hens.  

PubMed

Heat stress (HS) is a major problem experienced by the poultry industry during high-temperature conditions. The ability to manage the detrimental effects of HS can be attributed to multiple factors, including genetic background of flocks. The objective of the present study was to determine the genetic variation in HS effects on laying hens' physiological homeostasis. Ninety 28-wk-old White Leghorn hens of 2 strains were used: a commercial line of individually selected hens for high egg production, DeKalb XL (DXL), and a line of group-selected hens for high productivity and survivability, named kind gentle bird (KGB). Hens were randomly paired by strain and assigned to hot or control treatment for 14 d. Physical and physiological parameters were analyzed at d 8 and 14 posttreatment. Compared with controls, HS increased hen's core body temperature (P < 0.05) and decreased BW (P < 0.05) at d 8 and 14. Heat shock protein 70 concentrations in the liver were greater in hens exposed to HS (P < 0.05). Compared with DXL hens, KGB hens had higher heat shock protein 70 concentrations (P < 0.05). The hens' liver weight decreased following HS, with less of a response in the KGB line (P < 0.05). The data indicate HS has detrimental effects on the physiology of laying hens due to genetic variations. These data provide evidence that is valuable for determining genetic interventions for laying hens under HS. PMID:22700497

Felver-Gant, J N; Mack, L A; Dennis, R L; Eicher, S D; Cheng, H W

2012-07-01

231

Pathological derailment of genetically programmed plant meristem fate: beneath phytoplasma-induced growth pattern alterations  

Technology Transfer Automated Retrieval System (TEKTRAN)

In the life cycle of higher plants, it is the fate of meristem cells that determines the pattern of growth and development, and therefore plant morphotype and fertility. Floral transition, the turning point from vegetative growth to reproductive development, is achieved via genetically-programmed s...

232

Detection of Genetic Alterations in Breast Sentinel Lymph Node by Array- CGH.  

National Technical Information Service (NTIS)

The sentinel lymph node (SLN) is the first node in the mammary gland to harbor malignant cells in breast tumors with metastasis, and SLN positivity is an indication for axillary lymph node dissection. The purpose of our study is to identify specific genet...

L. R. Cavalli

2006-01-01

233

Detection of Genetic Alterations in Breast Sentinel Lymph Node by Array- CGH.  

National Technical Information Service (NTIS)

The sentinel lymph node (SLN) is the first node in the mammary gland to harbor malignant cells in breast tumors with metastasis, and SLN positivity is an indication for axillary lymph node dissection. The purpose of our study is to identify specific genet...

L. R. Cavalli

2005-01-01

234

Genetic Analysis of Familial Connective Tissue Alterations Associated With Cervical Artery Dissections Suggests Locus Heterogeneity  

Microsoft Academic Search

Background and Purpose—Cervical artery dissections (CAD) can be associated with connective tissue aberrations in skin biopsies. The analysis of healthy relatives of patients suggested that the connective tissue phenotype is familial with an autosomal dominant inheritance. Methods—We performed genetic linkage studies in 3 families of patients with CAD. Connective tissue phenotypes for the patients and all family members were assessed

Tina Wiest; Sonja Hyrenbach; Pinar Bambul; Birgit Erker; Alessandro Pezzini; Ingrid Hausser; Marie-Luise Arnold; Juan JoseMartin; Stefan Engelter; Philippe Lyrer; Otto Busse; Tobias Brandt; Caspar Grond-Ginsbach

2009-01-01

235

The hyperactive syndrome: Metanalysis of genetic alterations, pharmacological treatments and brain lesions which increase locomotor activity  

Microsoft Academic Search

The large number of transgenic mice realized thus far with different purposes allows addressing new questions, such as which animals, over the entire set of transgenic animals, show a specific behavioural abnormality. In the present study, we have used a metanalytical approach to organize a database of genetic modifications, brain lesions and pharmacological interventions that increase locomotor activity in animal

Davide Viggiano

2008-01-01

236

Biology and genetic aspects of gastrointestinal stromal tumors: KIT activation and cytogenetic alterations  

Microsoft Academic Search

Recent studies have done much to reveal the biological and genetic underpinnings of gastrointestinal stromal tumors (GISTs). Constitutive activation of the KIT receptor tyrosine kinase is a central pathogenetic event in most GISTs and generally results from oncogenic point mutations which can involve either extracellular or cytoplasmic domains of the receptor. Oncogenic mutations enable the KIT receptor to phosphorylate various

Michael C. Heinrich; Brian P. Rubin; B. Jack Longley; Jonathan A. Fletcher

2002-01-01

237

Genetic variation in defense chemistry in wild cabbages affects herbivores and their endoparasitoids.  

PubMed

Populations of wild Brassica oleracea L. grow naturally along the Atlantic coastlines of the United Kingdom and France. Over a very small spatial scale (i.e., <15 km) these populations differ in the expression of the defensive compounds, glucosinolates (GS). Thus far, very few studies have examined interactions between genetically distinct populations of a wild plant species and associated consumers in a multitrophic framework. Here, we compared the development of a specialist (Pieris rapae) and a generalist (Mamestra brassicae) insect herbivore and their endoparasitoids (Cotesia rubecula and Microplitis mediator, respectively) on three wild populations and one cultivar of B. oleracea under controlled greenhouse conditions. Herbivore performance was differentially affected by the plant population on which they were reared. Plant population influenced only development time and pupal mass in P. rapae, whereas plant population also had a dramatic effect on survival of M. brassicae. Prolonged development time in P. rapae corresponded with high levels of the indole GS, neoglucobrassicin, whereas reduced survival in M. brassicae coincided with high levels of the aliphatic GS, gluconapin and sinigrin. The difference between the two species can be explained by the fact that the specialist P. rapae is adapted to feed on plants containing GS and has evolved an effective detoxification system against aliphatic GS. The different B. oleracea populations also affected development of the endoparasitoids. Differences in food-plant quality for the hosts were reflected in adult size in C. rubecula and survival in M. mediator, and further showed that parasitoid performance is also affected by herbivore diet. PMID:18589526

Gols, Rieta; Wagenaar, R; Bukovinszky, Tibor; van Dam, Nicole M; Dicke, Marcel; Bullock, James M; Harvey, Jeffrey A

2008-06-01

238

Alterations in K-ras, APC and p53-multiple genetic pathway in colorectal cancer among Indians.  

PubMed

The incidence of colorectal cancer (CRC) is increasing rapidly in Asian countries during the past few decades, but no comprehensive analysis has been done to find out the exact cause of this disease. In this study, we investigated the frequencies of mutations and expression pattern of K-ras, APC (adenomatosis polyposis coli) and p53 in tumor, adjoining and distant normal mucosa and to correlate these alterations with patients clinicopathological parameters as well as with the survival. Polymerase chain reaction (PCR)-restriction digestion was used to detect mutations in K-ras and PCR-SSCP (Single Strand Conformation Polymorphism) followed by DNA sequencing was used to detect mutations in APC and p53 genes. Immunohistochemistry was used to detect the expression pattern of K-ras, APC and p53 proteins. The frequencies of mutations of K-ras, APC and p53 in 30 tumor tissues samples were 26.7 %, 46.7 % and 20 %, respectively. Only 3.3 % of tumors contained mutations in all the three genes. The most common combination of mutation was APC and p53 whereas mutation in both p53 and K-ras were extremely rare. There was no association between the mutations and expression pattern of K-ras, APC and p53 (p>0.05). In Indians, the frequency of alterations of K-ras and APC is similar as in Westerns, whereas the frequency of p53 mutation is slightly lower. The lack of multiple mutations in tumor specimens suggests that these genetic alterations might have independent influences on CRC development and there could be multiple alternative genetic pathways to CRC in our present study cohort. PMID:23526092

Malhotra, Pooja; Anwar, Mumtaz; Nanda, Neha; Kochhar, Rakesh; Wig, Jai Dev; Vaiphei, Kim; Mahmood, Safrun

2013-03-24

239

Genetic and Epigenetic Alterations of Lysophosphatidic Acid Receptor Genes in Rodent Tumors by Experimental Models  

PubMed Central

Lysophosphatidic acid (LPA) is a bioactive mediator and induces several biological effects, including cell proliferation, migration, morphogenesis and differentiation. LPA interacts with at least six G protein-coupled receptors (GPCRs), including LPA receptor-1 (LPA1), LPA2, LPA3, LPA4, LPA5 and LPA6. These receptors show different biological functions through the binding of LPA, depending on the type of cells. In human malignancies, a high level of LPA production was found in plasma and ascites in ovarian cancer cases. Moreover, aberrant expression levels of LPA receptor genes were detected in some cancer cells. Therefore, it is suggested that LPA receptors may be involved in the pathogenesis of tumor cells as well as LPA per se. Recently, we have reported that alterations of LPA receptor genes also occur in rodent tumors. In this review, we summarize the recent evidence in the investigations of LPA receptor alterations in rodent tumors by experimental models.

Tsujiuchi, Toshifumi; Okabe, Kyoko; Fukushima, Nobuyuki

2011-01-01

240

Transgenerational carcinogenesis: induction and transmission of genetic alterations and mechanisms of carcinogenesis  

Microsoft Academic Search

Parental exposure, i.e. germ cell exposure to radiation and chemicals, increased the incidence of tumors and malformations in the offspring, and the germ-line alterations that cause cancer are transmissible to further generations. However, tumor incidences were 100-fold higher than those of ordinary mouse mutations and there were apparent strain differences in the types of induced tumors. In human, higher risk

Taisei Nomura

2003-01-01

241

Population genetic structure of orchid bees (Euglossini) in anthropogenically altered landscapes  

Microsoft Academic Search

Habitat degradation and fragmentation are widespread phenomena in tropical regions. Negative effects on the biota are numerous,\\u000a ranging from interruption of gene flow among populations, to the loss of genetic diversity within populations, to a decline\\u000a in species richness over time. Orchid bees (Hymenoptera: Apidae: Euglossini) are of major conservation interest due to their\\u000a function as pollinators of numerous orchid

Y. Zimmermann; D. L. P. Schorkopf; R. F. A. Moritz; R. W. Pemberton; J. J. G. Quezada-Euan; T. Eltz

242

Brassica, Biotransformation and Cancer Risk: Genetic Polymorphisms Alter the Preventive Effects of Cruciferous Vegetables1  

Microsoft Academic Search

The chemoprotective effect of cruciferous vegetables is due to their high glucosinolate content and the capacity of glucosinolate metabolites, such as isothio- cyanates (ITC) and indoles, to modulate biotransformation enzyme systems (e.g., cytochromes P450 and conjugating enzymes). Data from molecular epidemiologic studies sug- gest that genetic and associated functional variations in biotransformation enzymes, particularly glutathione S-transferase (GST)M1 and GSTT1, which

Johanna W. Lampe; Sabrina Peterson

243

Genetic variants of human organic anion transporter 4 demonstrate altered transport of endogenous substrates  

PubMed Central

Apical reabsorption from the urine has been shown to be important for such processes as the maintenance of critical metabolites in the blood and the excretion of nephrotoxic compounds. The solute carrier (SLC) transporter OAT4 (SLC22A11) is expressed on the apical membrane of renal proximal tubule cells and is known to mediate the transport of a variety of xenobiotic and endogenous organic anions. Functional characterization of genetic variants of apical transporters thought to mediate reabsorption, such as OAT4, may provide insight into the genetic factors influencing the complex pathways involved in drug elimination and metabolite reclamation occurring in the kidney. Naturally occurring genetic variants of OAT4 were identified in public databases and by resequencing DNA samples from 272 individuals comprising 4 distinct ethnic groups. Nine total nonsynonymous variants were identified and functionally assessed using uptake of three radiolabeled substrates. A nonsense variant, R48Stop, and three other variants (R121C, V155G, and V155M) were found at frequencies of at least 2% in an ethnic group specific fashion. The L29P, R48Stop, and H469R variants displayed a complete loss of function, and kinetic analysis identified a reduced Vmax in the common nonsynonymous variants. Plasma membrane levels of OAT4 protein were absent or reduced in the nonfunctional variants, providing a mechanistic reason for the observed loss of function. Characterization of the genetic variants of reabsorptive transporters such as OAT4 is an important step in understanding variability in tubular reabsorption with important implications in innate homeostatic processes and drug disposition.

Shima, James E.; Komori, Takafumi; Taylor, Travis R.; Stryke, Doug; Kawamoto, Michiko; Johns, Susan J.; Carlson, Elaine J.; Ferrin, Thomas E.

2010-01-01

244

Genetic and environmental factors that affect gestation length in dairy cattle.  

PubMed

Genetic and environmental factors that might affect gestation length (GL) were investigated. Data included information from >11 million parturitions from 1999 through 2006 for 7 US dairy breeds. Effects examined were year, herd-year, month, and age within parity of conception; parturition code (sex and multiple-birth status); lactation length and standardized milk yield of cow; service sire; cow sire; and cow. All effects were fixed except for service sire, cow sire, and cow. Mean GL for heifers and cows, respectively, were 277.8 and 279.4 d for Holsteins, 278.4 and 280.0 d for Jerseys, 279.3 and 281.1 d for Milking Shorthorns, 281.6 and 281.7 d for Ayrshires, 284.8 and 285.7 d for Guernseys, and 287.2 and 287.5 d for Brown Swiss. Estimated standard deviations of GL were greatly affected by data restrictions but generally were approximately 5 to 6 d. Year effects on GL were extremely small, but month effects were moderate. For Holstein cows, GL was 2.0 d shorter for October conceptions than for January and February conceptions; 4.7 and 5.6 d shorter for multiple births of the same sex than for single-birth females and males, respectively; 0.8 d longer for lactations of < or =250 d than for lactations of > or =501 d; and 0.6 d shorter for standardized yield of < or =8,000 kg than for yield of > or =14,001 kg. Estimates for GL heritability from parities 2 to 5 were 33 to 36% for service sire and 7 to 12% for cow sire; corresponding estimates from parity 1 were 46 to 47% and 10 to 12%. Estimates of genetic correlations between effects of service sire and cow sire on GL were 0.70 to 0.85 for Brown Swiss, Holsteins, and Jerseys, which indicates that those traits likely are controlled by many of the same genes and can be used to evaluate each other. More accurate prediction of calving dates can help dairy producers to meet management requirements of pregnant animals and to administer better health care during high-risk phases of animals' lives. However, intentional selection for either shorter or longer GL is not recommended without consideration of its possible effect on other dependent traits (e.g., calving ease and stillbirth). PMID:19389985

Norman, H D; Wright, J R; Kuhn, M T; Hubbard, S M; Cole, J B; VanRaden, P M

2009-05-01

245

Alterations in the intracellular level of a protein subunit of human RNase P affect processing of tRNA precursors  

PubMed Central

The human ribonucleoprotein ribonuclease P (RNase P), processing tRNA, has at least 10 distinct protein subunits. Many of these subunits, including the autoimmune antigen Rpp38, are shared by RNase MRP, a ribonucleoprotein enzyme required for processing of rRNA. We here show that constitutive expression of exogenous, tagged Rpp38 protein in HeLa cells affects processing of tRNA precursors. Alterations in the site-specific cleavage and in the steady-state level of 3? sequences of the internal transcribed spacer 1 of rRNA are also observed. These processing defects are accompanied by selective shut-off of expression of Rpp38 and by low expression of the tagged protein. RNase P purified from these cells exhibits impaired activity in vitro. Moreover, inhibition of Rpp38 by the use of small interfering RNA causes accumulation of the initiator methionine tRNA precursor. Expression of other protein components, but not of the H1 RNA subunit, is coordinately inhibited. Our results reveal that normal expression of Rpp38 is required for the biosynthesis of intact RNase P and for the normal processing of stable RNA in human cells.

Cohen, Amit; Reiner, Robert; Jarrous, Nayef

2003-01-01

246

Does wheat genetically modified for disease resistance affect root-colonizing pseudomonads and arbuscular mycorrhizal fungi?  

PubMed

This study aimed to evaluate the impact of genetically modified (GM) wheat with introduced pm3b mildew resistance transgene, on two types of root-colonizing microorganisms, namely pseudomonads and arbuscular mycorrhizal fungi (AMF). Our investigations were carried out in field trials over three field seasons and at two locations. Serial dilution in selective King's B medium and microscopy were used to assess the abundance of cultivable pseudomonads and AMF, respectively. We developed a denaturing gradient gel electrophoresis (DGGE) method to characterize the diversity of the pqqC gene, which is involved in Pseudomonas phosphate solubilization. A major result was that in the first field season Pseudomonas abundances and diversity on roots of GM pm3b lines, but also on non-GM sister lines were different from those of the parental lines and conventional wheat cultivars. This indicates a strong effect of the procedures by which these plants were created, as GM and sister lines were generated via tissue cultures and propagated in the greenhouse. Moreover, Pseudomonas population sizes and DGGE profiles varied considerably between individual GM lines with different genomic locations of the pm3b transgene. At individual time points, differences in Pseudomonas and AMF accumulation between GM and control lines were detected, but they were not consistent and much less pronounced than differences detected between young and old plants, different conventional wheat cultivars or at different locations and field seasons. Thus, we conclude that impacts of GM wheat on plant-beneficial root-colonizing microorganisms are minor and not of ecological importance. The cultivation-independent pqqC-DGGE approach proved to be a useful tool for monitoring the dynamics of Pseudomonas populations in a wheat field and even sensitive enough for detecting population responses to altered plant physiology. PMID:23372672

Meyer, Joana Beatrice; Song-Wilson, Yi; Foetzki, Andrea; Luginbühl, Carolin; Winzeler, Michael; Kneubühler, Yvan; Matasci, Caterina; Mascher-Frutschi, Fabio; Kalinina, Olena; Boller, Thomas; Keel, Christoph; Maurhofer, Monika

2013-01-23

247

Genetic Counselor Workforce. Training Programs, Professional Practice, and Issues Affecting Supply and Demand.  

National Technical Information Service (NTIS)

The demand for genetic services is expected to increase significantly as the Hu-man Genome Project and other research yield scientific advances with clinical applications. At this relatively early stage in the new genetics revolution, the issues involved ...

J. A. Cooksey

2000-01-01

248

Investigations on the organization of genetic loci in Drosophila melanogaster : lethal mutations affecting 6-phosphogluconate dehydrogenase and their suppression  

Microsoft Academic Search

The molecular nature of lethal and semilethal mutations in the Pgd locus of D. melanogaster coding for 6-phosphogluconate dehydrogenase (6PGD) was studied. All the 11 mutations affect the structural gene of the Pgd locus: 3 semilethal mutations resulted in altered 6PGD molecules with decreased catalytic activities; the rest 8 lethals were “null” alleles characterized by mutant polypeptides capable of reacting

V. A. Gvozdev; T. I. Gerasimova; G. L. Kogan; J. M. Rosovsky

1977-01-01

249

Maternal nutritional condition and genetic differentiation affect brood size and offspring body size in Nicrophorus.  

PubMed

In most animal species, brood size and body size exhibit some variation within and between populations. This is also true for burying beetles (genus Nicrophorus), a group in which the body size of offspring depends critically on the number of offspring competing for food due to the discrete nature of resource used for larval nutrition (vertebrate carcasses). In one species, brood size and body size are correlated with population density, and appear to be phenotypically plastic. We investigated potential proximate causes of between-population variation in brood size and body size in two species, Nicrophorus vespilloides and Nicrophorus defodiens. Our first experiment supported the notion that brood size is phenotypically plastic, because it was affected by environmental variation in adult nutritional condition. We found that the pre-breeding nutritional status of female N. vespilloides affected the number of eggs they laid, the number of surviving larvae in their broods, and the body size of their offspring. We do not know whether this plasticity is adaptive because greater offspring body size confers an advantage in contests over breeding resources, or whether starved females are constrained to produce smaller clutches because they cannot fully compensate for their poor pre-breeding nutritional status by feeding from the carcass. Our second experiment documents that brood size, specifically the infanticidal brood-size adjustment behavior, has undergone genetic differentiation between two populations of N. defodiens. Even under identical breeding conditions with identical numbers of first-instar larvae, females descended from the two populations produced broods of different size with corresponding differences in offspring body size. PMID:17702555

Steiger, Sandra; Richter, Katja; Müller, Josef K; Eggert, Anne-Katrin

2007-08-15

250

Genetic Variation of the IL-28B Promoter Affecting Gene Expression  

PubMed Central

The current standard of care for the treatment of chronic hepatitis C is pegylated interferon-? (PEG-IFN?) and ribavirin (RBV). The treatment achieves a sustained viral clearance in only approximately 50% of patients. Recent whole genome association studies revealed that single nucleotide polymorphisms (SNPs) around IL-28B have been associated with response to the standard therapy and could predict treatment responses at approximately 80%. However, it is not clear which SNP is most informative because the genomic region containing significant SNPs shows strong linkage disequilibrium. We focused on SNPs in close proximity to the IL-28B gene to evaluate the function of each and identify the SNP affecting the IL-28B expression level most. The structures of IL-28A/B from 5? to 3?-UTR were determined by complete cDNA cloning. Both IL-28A and 28B genes consisted of 6 exons, differing from the CCDS data of NCBI. Two intron SNPs and a nonsynonymous SNP did not affect IL-28B gene function and expression levels but a SNP located in the proximal promoter region influenced gene expression. A (TA) dinucleotide repeat, rs72258881, located in the promoter region was discovered by our functional studies of the proximal SNPs upstream of IL-28B; the transcriptional activity of the promoter increased gradually in a (TA)n length-dependent manner following IFN-? and lipopolysaccharide stimulation. Healthy Japanese donors exhibited a broad range of (TA) dinucleotide repeat numbers from 10 to 18 and the most prevalent genotype was 12/12 (75%), differing from the database (13/13). However, genetic variation of IL-28A corresponding to that of IL-28B was not detected in these Japanese donors. These findings suggest that the dinucleotide repeat could be associated with the transcriptional activity of IL-28B as well as being a marker to improve the prediction of the response to interferon-based hepatitis C virus treatment.

Sugiyama, Masaya; Tanaka, Yasuhito; Wakita, Takaji; Nakanishi, Makoto; Mizokami, Masashi

2011-01-01

251

Genetic Alterations within the DENND1A Gene in Patients with Polycystic Ovary Syndrome (PCOS).  

PubMed

Polycystic ovary syndrome (PCOS), the most common endocrine disease among premenopausal women, is caused by both genes and environment. We and others previously reported association between single nucleotide polymorphisms (SNPs) in the DENND1A gene and PCOS. We therefore sequenced the DENND1A gene in white patients with PCOS to identify possible alterations that may be implicated in the PCOS pathogenesis. Patients were referred with PCOS and/or hirsutism between 1998 and 2011 (n = 261). PCOS was diagnosed according to the Rotterdam criteria (n = 165). Sequence analysis was performed in 10 patients with PCOS. Additional patients (n = 251) and healthy female controls (n = 248) were included for SNP genotyping. Patients underwent clinical examination including Ferriman-Gallwey score (FG-score), biochemical analyses and transvaginal ultrasound. Mutation analysis was carried out by bidirectional sequencing. SNP genotyping was tested by allelic discrimination in real-time PCR in the additional patients and controls. Sequencing of the DENND1A gene identified eight SNPs; seven were not known to be associated with any diseases. One missense SNP was detected (rs189947178, A/C), potentially altering the structural conformation of the DENND1A protein. SNP genotyping of rs189947178 showed significantly more carriers among patients with PCOS and moderate hirsutism compared to controls. However, due to small sample size and lack of multiple regression analysis supporting an association between rs189947178 and FG-score or PCOS diagnosis, this could be a false positive finding. In conclusion, sequence analysis of the DENND1A gene of patients with PCOS did not identify alterations that alone could be responsible for the PCOS pathogenesis, but a missense SNP (rs189947178) was identified in one patient and significantly more carriers of rs189947178 were found among patients with PCOS and moderate hirsutism vs. controls. Additional studies with independent cohort are needed to confirm this due to the small sample size of this study. PMID:24086769

Eriksen, Mette B; Nielsen, Michael F B; Brusgaard, Klaus; Tan, Qihua; Andersen, Marianne S; Glintborg, Dorte; Gaster, Michael

2013-09-27

252

Genetic Alterations within the DENND1A Gene in Patients with Polycystic Ovary Syndrome (PCOS)  

PubMed Central

Polycystic ovary syndrome (PCOS), the most common endocrine disease among premenopausal women, is caused by both genes and environment. We and others previously reported association between single nucleotide polymorphisms (SNPs) in the DENND1A gene and PCOS. We therefore sequenced the DENND1A gene in white patients with PCOS to identify possible alterations that may be implicated in the PCOS pathogenesis. Patients were referred with PCOS and/or hirsutism between 1998 and 2011 (n = 261). PCOS was diagnosed according to the Rotterdam criteria (n = 165). Sequence analysis was performed in 10 patients with PCOS. Additional patients (n = 251) and healthy female controls (n = 248) were included for SNP genotyping. Patients underwent clinical examination including Ferriman-Gallwey score (FG-score), biochemical analyses and transvaginal ultrasound. Mutation analysis was carried out by bidirectional sequencing. SNP genotyping was tested by allelic discrimination in real-time PCR in the additional patients and controls. Sequencing of the DENND1A gene identified eight SNPs; seven were not known to be associated with any diseases. One missense SNP was detected (rs189947178, A/C), potentially altering the structural conformation of the DENND1A protein. SNP genotyping of rs189947178 showed significantly more carriers among patients with PCOS and moderate hirsutism compared to controls. However, due to small sample size and lack of multiple regression analysis supporting an association between rs189947178 and FG-score or PCOS diagnosis, this could be a false positive finding. In conclusion, sequence analysis of the DENND1A gene of patients with PCOS did not identify alterations that alone could be responsible for the PCOS pathogenesis, but a missense SNP (rs189947178) was identified in one patient and significantly more carriers of rs189947178 were found among patients with PCOS and moderate hirsutism vs. controls. Additional studies with independent cohort are needed to confirm this due to the small sample size of this study.

Eriksen, Mette B.; Nielsen, Michael F. B.; Brusgaard, Klaus; Tan, Qihua; Andersen, Marianne S.; Glintborg, Dorte; Gaster, Michael

2013-01-01

253

Abundance and Genetic Diversity of nifH Gene Sequences in Anthropogenically Affected Brazilian Mangrove Sediments  

PubMed Central

Although mangroves represent ecosystems of global importance, the genetic diversity and abundance of functional genes that are key to their functioning scarcely have been explored. Here, we present a survey based on the nifH gene across transects of sediments of two mangrove systems located along the coast line of São Paulo state (Brazil) which differed by degree of disturbance, i.e., an oil-spill-affected and an unaffected mangrove. The diazotrophic communities were assessed by denaturing gradient gel electrophoresis (DGGE), quantitative PCR (qPCR), and clone libraries. The nifH gene abundance was similar across the two mangrove sediment systems, as evidenced by qPCR. However, the nifH-based PCR-DGGE profiles revealed clear differences between the mangroves. Moreover, shifts in the nifH gene diversities were noted along the land-sea transect within the previously oiled mangrove. The nifH gene diversity depicted the presence of nitrogen-fixing bacteria affiliated with a wide range of taxa, encompassing members of the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, and also a group of anaerobic sulfate-reducing bacteria. We also detected a unique mangrove-specific cluster of sequences denoted Mgv-nifH. Our results indicate that nitrogen-fixing bacterial guilds can be partially endemic to mangroves, and these communities are modulated by oil contamination, which has important implications for conservation strategies.

Dias, Armando Cavalcante Franco; Pereira e Silva, Michele de Cassia; Cotta, Simone Raposo; Dini-Andreote, Francisco; Soares, Fabio Lino; Salles, Joana Falcao; Azevedo, Joao Lucio; van Elsas, Jan Dirk

2012-01-01

254

Citrus Leaf Volatiles as Affected by Developmental Stage and Genetic Type  

PubMed Central

Major volatiles from young and mature leaves of different citrus types were analyzed by headspace-solid phase microextraction (HS-SPME)-GC-MS. A total of 123 components were identified form nine citrus cultivars, including nine aldehydes, 19 monoterpene hydrocarbons, 27 oxygenated monoterpenes, 43 sesquiterpene hydrocarbons, eight oxygenated sesquiterpenes, two ketones, six esters and nine miscellaneous. Young leaves produced higher amounts of volatiles than mature leaves in most cultivars. The percentage of aldehyde and monoterpene hydrocarbons increased, whilst oxygenated monoterpenes and sesquiterpenes compounds decreased during leaf development. Linalool was the most abundant compound in young leaves, whereas limonene was the chief component in mature ones. Notably, linalool content decreased, while limonene increased, during leaf development in most cultivars. Leaf volatiles were also affected by genetic types. A most abundant volatile in one or several genotypes can be absent in another one(s), such as limonene in young leaves of lemon vs. Satsuma mandarin and ?-terpinene in mature leaves of three genotypes vs. the other four. Compositional data was subjected to multivariate statistical analysis, and variations in leaf volatiles were identified and clustered into six groups. This research determining the relationship between production of major volatiles from different citrus varieties and leaf stages could be of use for industrial and culinary purposes.

Azam, Muhammad; Jiang, Qian; Zhang, Bo; Xu, Changjie; Chen, Kunsong

2013-01-01

255

Region-Specific Genetic Alterations in the Aging Hippocampus: Implications For Cognitive Aging  

PubMed Central

Aging is associated with cognitive decline in both humans and animals and of all brain regions, the hippocampus appears to be particularly vulnerable to senescence. Age-related spatial learning deficits result from alterations in hippocampal connectivity and plasticity. These changes are differentially expressed in each of the hippocampal fields known as cornu ammonis 1 (CA1), cornu ammonis 3 (CA3), and the dentate gyrus. Each sub-region displays varying degrees of susceptibility to aging. For example, the CA1 region is particularly susceptible in Alzheimer's disease while the CA3 region shows vulnerability to stress and glucocorticoids. Further, in animals, aging is the main factor associated with the decline in adult neurogenesis in the dentate gyrus. This review discusses the relationship between region-specific hippocampal connectivity, morphology, and gene expression alterations and the cognitive deficits associated with senescence. In particular, data are reviewed that illustrate how the molecular changes observed in the CA1, CA3, and dentate regions are associated with age-related learning deficits. This topic is of importance because increased understanding of how gene expression patterns reflect individual differences in cognitive performance is critical to the process of identifying new and clinically useful biomarkers for cognitive aging.

Burger, Corinna

2010-01-01

256

On the genetics of hypodontia and microdontia: synergism or allelism of major genes in a family with six affected members  

Microsoft Academic Search

Familial severe hypodontia of the permanent dentition is a rare condition. The genetics of this entity remains unclear and several modes of inheritance have been suggested. We report here an increase in the number of congenitally missing teeth after the mating of affected subjects from two unrelated Norwegian families. This condition may be the result of allelic mutations at a

S P Lyngstadaas; H Nordbo; T Gedde-Dahl; P S Thrane

1996-01-01

257

Psychosocial and cultural factors affecting the perceived risk of genetically modified food: an overview of the literature  

Microsoft Academic Search

The rapid globalization of the world economy has increased the need for an astute understanding of cultural differences in perceptions, values, and ways of thinking about new food technologies. In this paper, we describe how socio-psychological and cultural factors may affect public perceptions of the risk of genetically modified (GM) food. We present psychological, sociological, and anthropological research on risk

Melissa L. Finucane; Joan L. Holup

2005-01-01

258

Status of the search for a major genetic locus for affective disorder in the Old Order Amish  

Microsoft Academic Search

We have resumed the search for an autosomal linkage with affective disorder in the Old Order Amish and report the pairwise linkage results after screening 185 marked loci. No positive evidence of genetic linkage was found, and we estimate that roughly 23% of the autosomal genome has been excluded from linkage.

Andrew J. Pakstis; Judith R. Kidd; Carmela M. Castiglione; Kenneth K. Kidd

1991-01-01

259

Evaluation of molecular genetic alterations associated with tumor progression in a case of gliomatosis cerebri.  

PubMed

Gliomatosis cerebri (GC) is a rare tumor characterized by widespread infiltration of the brain and spinal cord. Although GC usually demonstrates histomorphological features of a low-grade tumor, the formation of secondary highly malignant tumor regions may occur. In order to reveal molecular genetic changes associated with tumor progression in GC, we analyzed factors known to be associated with malignant progression in common astocytomas in an unusual GC case of an 18-year-old patient suffering from this disease for almost 7 years. We detected allelic losses in the Rb gene and in exon 4 of the TP53 gene in a tumor region corresponding to a glioblastoma multiforme. EGFR or MDM2 gene amplifications were absent, and no PTEN mutation or allelic loss on chromosome 10 could be detected. Moreover, compared to tumor-free brain tissue of this patient, tumor regions showed increased EGFR expression. These findings show that malignant progression in GC might be associated with the acquisition of molecular genetic changes also found in low-grade astrocytomas with progression to secondary glioblastoma. These data support the notion that GC can be regarded as a subtype of a common astrocytoma. PMID:16955219

Braeuninger, Stefan; Schneider-Stock, Regine; Kirches, Elmar; Powers, James M; Korones, David N; Mawrin, Christian

2006-09-06

260

Genetic and epigenetic alterations are involved in the regulation of TPM1 in cholangiocarcinoma.  

PubMed

Cholangiocarcinoma is a malignant tumor originating from biliary epithelial cells. The tumor suppressor gene tropomyosin 1 (TPM1) is downregulated in several human cancer types; however, its expression status in cholangiocarcinoma is still unknown. We elucidated TPM1 expression and its regulation mechanism in cholangiocarcinoma. Real-time (RT)-PCR, western blot analysis and immunohistochemistry were performed to examine TPM1 expression levels in cholangiocarcinoma cell lines and tumor tissues. Cell lines were treated with lentiviral vector containing the miR-21 knockdown and inhibitors of genetic and epigenetic mechanisms (manumycin A, LY294002, U0126, DAC and TSA), and the TPM1 expression change was observed by RT-PCR and western blot analyses. Cell proliferation, apoptosis and migration were evaluated by water-soluble tetrazolium salt (WST-1) assay, flow cytometry and wound healing experiments, respectively. TPM1 was downregulated in the intrahepatic cholangiocarcinoma cells (HuCCT1) and upregulated in the extrahepatic cholangiocarcinoma cells (QBC939) compared with normal intrahepatic biliary epithelial cells (HIBEC). TPM1 stained negative in the intrahepatic cholangiocarcinoma tissues, as revealed by immunohistochemistry, although there was no significant difference in staining of the intrahepatic cholangiocarcinoma tissues and adjacent non-cancer tissues. RAS and two important downstream signaling pathways (RAS/PI3K/AKT and RAS/MEK/ERK) were involved in TPM1 regulation and inhibition of the epigenetic mechanisms such as DNA methylation, histone deacetylation and miR-21 upregulation upregulated TPM1 expression. Inhibitors of genetic and epigenetic mechanisms (manumycin A, LY294002, U0126, DAC and TSA) inhibited cell proliferation and migration and induced apoptosis. These data indicated that TPM1 is downregulated in HuCCT1 cells and that the Ras signaling pathway as well as DNA methylation, histone deacetylation and miR-21 upregulation play important roles in the suppression of TPM1 expression in HuCCT1 cells. Thus, compounds that inhibit genetic and epigenetic mechanisms may be promising agents in treating cholangiocarcinoma. PMID:23254774

Yang, Wei; Wang, Xiaoyuan; Zheng, Wei; Li, Kedong; Liu, Haofeng; Sun, Yueming

2012-12-17

261

QTL mapping reveals the genetic architecture of loci affecting pre- and post-zygotic isolating barriers in Louisiana Iris  

PubMed Central

Background Hybridization among Louisiana Irises has been well established and the genetic architecture of reproductive isolation is known to affect the potential for and the directionality of introgression between taxa. Here we use co-dominant markers to identify regions where QTL are located both within and between backcross maps to compare the genetic architecture of reproductive isolation and fitness traits across treatments and years. Results QTL mapping was used to elucidate the genetic architecture of reproductive isolation between Iris fulva and Iris brevicaulis. Homologous co-dominant EST-SSR markers scored in two backcross populations between I. fulva and I. brevicaulis were used to generate genetic linkage maps. These were used as the framework for mapping QTL associated with variation in 11 phenotypic traits likely responsible for reproductive isolation and fitness. QTL were dispersed throughout the genome, with the exception of one region of a single linkage group (LG) where QTL for flowering time, sterility, and fruit production clustered. In most cases, homologous QTL were not identified in both backcross populations, however, homologous QTL for flowering time, number of growth points per rhizome, number of nodes per inflorescence, and number of flowers per node were identified on several linkage groups. Conclusions Two different traits affecting reproductive isolation, flowering time and sterility, exhibit different genetic architectures, with numerous QTL across the Iris genome controlling flowering time and fewer, less distributed QTL affecting sterility. QTL for traits affecting fitness are largely distributed across the genome with occasional overlap, especially on LG 4, where several QTL increasing fitness and decreasing sterility cluster. Given the distribution and effect direction of QTL affecting reproductive isolation and fitness, we have predicted genomic regions where introgression may be more likely to occur (those regions associated with an increase in fitness and unlinked to loci controlling reproductive isolation) and those that are less likely to exhibit introgression (those regions linked to traits decreasing fitness and reproductive isolation).

2012-01-01

262

[Glial and glioneuronal tumors in adults and children: main genetic alterations and towards a histomolecular classification].  

PubMed

Glial and glioneuronal tumors in children and adult demonstrate distinctive clinical, neuroradiological and molecular features depending on the pathological subtype and within a same subgroup according to the age. In children, gliomas are mainly located in the infratentorial part of the brain. They are most often benign and circumscribed but infiltrative tumors with dismal prognosis are recorded within the pons (DIGP) or the thalamus. Glioblastomas are very rare in children. In contrast, gliomas in adult mainly occur in the cerebral hemispheres and the most frequent subtype is glioblastoma. Glioneuronal tumors mainly occurred in children and young adults. In addition, although pilocytic astrocytomas, pleomorphic xanthoastrocytomas and gangliogliomas are classified into different subgroups according to the WHO 2007 classification, these tumors demonstrate similar neuroradiological findings: they are cystic with contrast enhancement of a mural nodule. Major advances have been made these last five years in the discovery of some master genes that are involved in gliomagenesis and point out differences between children and adults. In adults, infiltrative gliomas can be classified into two major subgroups depending on the existence or not of IDH mutations. IDH-dependent gliomagenesis encompasses diffuse grade II and grade III (they can also show additional molecular alterations such as TP53 mutation or 1p19q codeletion) and secondary glioblastomas. IDH-independent gliomagenesis include triple negative grade II gliomas, gliomatosis cerebri (grade III) and de novo glioblastomas. Pilocytic astrocytomas, pleomorphic xanthoastrocytomas and gangliogliomas share in common BRAF alterations. However, KIAA1549-BRAF fusion characterizes pilocytic astrocytomas whereas V600E BRAF mutation is mainly recorded in pleomorphic xanthoastrocytomas and gangliogliomas. PMID:23831947

Figarella-Branger, Dominique; Chappe, Céline; Padovani, Laëtitia; Mercurio, Sandy; Colin, Carole; Forest, Fabien; Bouvier, Corinne

263

Selective Deletion of a Cell Cycle Checkpoint Kinase (ATR) Reduces Neurogenesis and Alters Responses in Rodent Models of Behavioral Affect  

PubMed Central

Hippocampal function has been implicated in mood and anxiety disorders, as well as in the response to antidepressant (AD) treatment. However, the significance of new neurons in the therapeutic mechanism of ADs remains unclear. In this study, the proliferation of new neurons was inhibited through conditional deletion of ataxia telangeictasia-mutated and rad-3 related (ATR), a cell cycle checkpoint kinase, and cellular and behavioral outcomes following AD exposure were evaluated. ATR was conditionally deleted by microinjecting a Cre recombinase-expressing virus into the hippocampus of floxed-ATR mice. Behavioral assessment in multiple rodent models of affective state revealed anxiolytic-like behavior in the elevated zero maze, marble burying test, and novelty-induced hypophagia (NIH) test. The efficacy of chronic desipramine (DMI) treatment was evaluated in the NIH test, as this paradigm is thought to be sensitive to increases in neurogenesis by chronic AD exposure. Chronic exposure to DMI reduced hyponeophagia in the NIH test in control mice, whereas DMI had no behavioral effect in ATR-deleted mice. Although DMI did not alter cell proliferation in either group, it did produce a robust increase in dendritic spine density in control mice, indicative of enhanced neuronal plasticity. This effect of DMI on spine density was severely attenuated following ATR deletion. These findings demonstrate that reductions in basal neurogenesis produce an anxiolytic phenotype and reduce AD efficacy in behaviors requiring chronic exposure. Furthermore, attenuated capacity for synaptic remodeling may underlie these behaviors. ATR deletion may serve as a valuable model to study the various proposed roles of newborn neurons in the hippocampus.

Onksen, Jennifer L; Brown, Eric J; Blendy, Julie A

2011-01-01

264

Selective deletion of a cell cycle checkpoint kinase (ATR) reduces neurogenesis and alters responses in rodent models of behavioral affect.  

PubMed

Hippocampal function has been implicated in mood and anxiety disorders, as well as in the response to antidepressant (AD) treatment. However, the significance of new neurons in the therapeutic mechanism of ADs remains unclear. In this study, the proliferation of new neurons was inhibited through conditional deletion of ataxia telangeictasia-mutated and rad-3 related (ATR), a cell cycle checkpoint kinase, and cellular and behavioral outcomes following AD exposure were evaluated. ATR was conditionally deleted by microinjecting a Cre recombinase-expressing virus into the hippocampus of floxed-ATR mice. Behavioral assessment in multiple rodent models of affective state revealed anxiolytic-like behavior in the elevated zero maze, marble burying test, and novelty-induced hypophagia (NIH) test. The efficacy of chronic desipramine (DMI) treatment was evaluated in the NIH test, as this paradigm is thought to be sensitive to increases in neurogenesis by chronic AD exposure. Chronic exposure to DMI reduced hyponeophagia in the NIH test in control mice, whereas DMI had no behavioral effect in ATR-deleted mice. Although DMI did not alter cell proliferation in either group, it did produce a robust increase in dendritic spine density in control mice, indicative of enhanced neuronal plasticity. This effect of DMI on spine density was severely attenuated following ATR deletion. These findings demonstrate that reductions in basal neurogenesis produce an anxiolytic phenotype and reduce AD efficacy in behaviors requiring chronic exposure. Furthermore, attenuated capacity for synaptic remodeling may underlie these behaviors. ATR deletion may serve as a valuable model to study the various proposed roles of newborn neurons in the hippocampus. PMID:21248719

Onksen, Jennifer L; Brown, Eric J; Blendy, Julie A

2011-01-19

265

Altered Seasonality and Magnitude of Rainfall Affects Soil Respiration and Nitrous Oxide Fluxes in California Annual Grassland  

NASA Astrophysics Data System (ADS)

Currently, climate models do not agree on how rising concentrations of CO2 and other greenhouse gases will affect rainfall in California. Changes in moisture regime will likely alter rates of carbon (C) loss via soil respiration, as well as fluxes of N2O. Moisture availability can also affect plant productivity in highly seasonal environments. We examined the consequences of wetter conditions in an annual grassland in the Sierra foothills of northern California by extending the duration of the wet season by about 5 weeks and augmenting total annual rainfall by approximately 50 %. Discrete wet-up events took place prior to the onset of natural rains (early October 2003) and early in the drought period (May 2004). Soil respiration, N2O and CH4 effluxes, N mineralization, and above- and belowground plant production were measured in treatment and control plots over a one-year period. Soil CO2 fluxes for the first treatment year, though large, were not statistically different between wet and control plots (1078 \\pm148 g C m-2 and 1006 \\pm138 g C m-2, respectively). The combined wet-up events comprised 17 % of the soil respiration over the 12-month period in treated plots, about twice as much C released by control plots during the same time interval. Aboveground biomass was similar between wetted and control plots (415 \\pm45 g m-2 y-1 and 374 \\pm36 g m-2 y-1, respectively), while root biomass increased significantly with wetting during the first year of treatment (179 \\pm23 g m-2 y-1 and 111 \\pm13 g m-2 y-1 for treatment and control plots, respectively). The additional biomass C gained in treatment plots (53 g C m-2) partly offset the greater losses from respired C observed in treatment plots (72 g C m-2). Nitrous oxide emissions were low to negligible during the year with the exception of the time directly following wet-up, when N2O emissions averaged over 78\\pm13 ng N cm-2 h-1. Our first year of water manipulation in annual grasslands suggests that increased water availability via early and late rainfall events releases large pulses of CO2, increases belowground C inputs, and increases N2O emissions.

Chou, W. W.; Silver, W. L.; Jackson, R. D.; Allen-Diaz, B.

2004-12-01

266

Variation in chlorobenzoate catabolism by Pseudomonas putida P111 as a consequence of genetic alterations  

SciTech Connect

Chlorobenzoates are key intermediates in the degradative pathways of polychlorinated biphenyls and benzoate herbicides. Bacteria that cometabolize these pollutants generally accumulate chlorobenzoates because they are not able to grow on them. Special interest has been focused on ortho-chlorobenzoates because they are more refractory to biodegradation. In all of these studies the enzyme responsible for the first attack on the ortho-chlorobenzoates possesses minimal or negligible activity with meta- or para-chlorobenzoates. This study reports evidence for the existence of two separate benzoate dioxygenases in Pseudomonas putida P111 and for the transpostional nature of the clc operon, on the basis of genetic investigations of different phenotypic variants of this strain. 42 refs., 4 figs., 1 tab.

Brenner, V.; Focht, D.D. (Univ. of California, Riverside, CA (United States)); Hernandez, B.S. (Univ. of Panama (Panama))

1993-09-01

267

Genetic alterations in hepatocellular carcinomas: association between loss of chromosome 4q and p53 gene mutations  

PubMed Central

The major risk factors for hepatocellular carcinomas (HCC) in high incidence areas include infection with hepatitis B and C viruses (HBV, HCV) and exposure to aflatoxin. Genetic alterations in 24 liver resection specimens from Shanghai and Qidong were studied. Hepatitis B virus was integrated in all patient samples, and a null phenotype for the GSTM1 enzyme was present in 63% of patients. Alteration of p53 was present in 95% (23/24) of cases: mutations of the p53 gene in 12 HCC, p53 overexpression in 13 and loss of heterozygosity (LOH) of chromosome 17p in 17. All seven HCCs with a p53 mutation from Qidong and three of five from Shanghai had the aflatoxin-associated point mutation with a G to T transversion at codon 249, position 3. No HCC had microsatellite instability. LOH of chromosome 4q, 1p, 16q and 13q was present in 50%, 46%, 42% and 38%, respectively, and 4q was preferentially lost in HCCs containing a p53 mutation: LOH of 4q was present in 75% (9/12) of HCC with, but only 25% (3/12) of HCC without, a p53 gene mutation (P = 0.01). These data indicate a possible interaction between p53 gene mutation and 4q loss in the pathogenesis of HCC. © 1999 Cancer Research Campaign

Rashid, A; Wang, J-S; Qian, G-S; Lu, B-X; Hamilton, S R; Groopman, J D

1999-01-01

268

Progressive increase of genetic alteration in urinary bladder cancer by combined allelotyping analysis and comparative genomic hybridization.  

PubMed

Bladder cancer is the ninth most common cancer in the world. Urothelial carcinoma (formerly known as transitional cell carcinoma) comprises the majority of bladder cancers. In order to decipher the genetic alteration leading to the carcinogenesis of urothelial cancer, we performed genome-wide allelotyping analysis using 384 microsatellite markers spanning 22 autosomes together with comparative genomic hybridization (CGH) in 21 urothelial cancer. High frequency of allelic imbalance was observed in chromosome arm 1q (61.9%), 3p (61.9%), 4q (66.67%), 8p (57.14%), 9p (76.2%) and 9q (66.67%). Allelic imbalance with frequency above average was also observed in chromosome arm 2q, 10p, 10q, 11p, 11q, 12q, 13q, 15q, 17p and 19q. The allelic imbalance of each case and fractional allelic loss for each chromosome was associated with higher tumor grade and stage (P<0.05). We have also delineated several minimal deletion regions on chromosome 3p, 4q, 8p, 9p, 9q, 11p, 13q, 16q and 17p. By CGH analysis, common chromosomal alterations included gain of 1p, 1q, 12q, 16p, 17q and 19p as well as loss of 4q and 9p in most of the cases. Our findings may provide valuable information to locate putative oncogenes and tumor suppressor genes in the carcinogenesis of bladder cancer in this locality. PMID:19287953

Chan, Michael W Y; Hui, Angela Bik-Yu; Yip, Sidney Kam-Hung; Ng, Chi-Fai; Lo, Kwok-Wai; Tong, Joanna H M; Chan, Anthony W H; Cheung, Ho Y; Wong, Wai S; Chan, Peter S F; Lai, Fernand M M; To, Ka-Fai

2009-04-01

269

ALTERING THE PHYSICAL ENVIRONMENT AFFECTS GROWTH, MORPHOGENESIS AND ESSENTIAL OIL PRODUCTION IN MENTHA SPICATA L. SHOOTS IN VITRO  

Technology Transfer Automated Retrieval System (TEKTRAN)

Altering the physical environment profoundly alters the growth (fresh weight), morphogenesis (leave, root and shoot numbers) and secondary metabolism [i.e., production of the monoterpene (-)-carvone] of Mentha spicata L. (spearmint) shoots cultured on Murashige and Skoog medium. The type of physica...

270

Genetic structure of sibling butterfly species affected by Wolbachia infection sweep: evolutionary and biogeographical implications.  

PubMed

It was recently recognized that in Japan, the common yellow butterfly, Eurema hecabe, consists of two sibling species, which have been unnamed yet and tentatively called yellow (Y) type and brown (B) type. We investigated the diversity of nuclear and mitochondrial genes in Japanese populations of Y type and B type of E. hecabe. The phylogeny based on nuclear genes agreed with the distinction between Y type and B type, which had been also supported by a wide array of biological data. However, the phylogeny based on mitochondrial genes did not reflect the distinction. PCR survey of Wolbachia revealed that B-type populations were all infected while Y-type populations contained both infected and uninfected individuals. A single genotype of Wolbachia, which was inferred to be a CI-inducing strain from their wsp gene sequence, was prevalent in these populations. Notably, the mitochondrial phylogeny was in perfect agreement with the pattern of Wolbachia infection, suggesting that the Wolbachia infection had affected the mitochondrial genetic structure of the host insects. Probably, the Wolbachia strain and the associated mitochondrial genomes have been occasionally introduced from B-type populations to Y-type populations through migration and subsequent interspecific hybridization, and CI-driven population sweep has been spreading the Wolbachia strain and the particular mitochondrial haplotypes, which originated from B-type populations, into Y-type populations. On the basis of these results together with the geological and biogeographical knowledge of the Japanese Archipelago, we proposed an evolutionary hypothesis on the invasion and spread of Wolbachia infection in B-type and Y-type of E. hecabe. PMID:16599969

Narita, Satoko; Nomura, Masashi; Kato, Yoshiomi; Fukatsu, Takema

2006-04-01

271

Medea selfish genetic elements as tools for altering traits of wild populations: A theoretical analysis  

PubMed Central

One strategy for controlling transmission of insect-borne disease involves replacing the native insect population with transgenic animals unable to transmit disease. Population replacement requires a drive mechanism to ensure the rapid spread of linked transgenes, the presence of which may result in a fitness cost to carriers. Medea selfish genetic elements have the feature that when present in a female, only offspring that inherit the element survive, a behavior that can lead to spread. Here we derive equations that describe the conditions under which Medea elements with a fitness cost will spread, and the equilibrium allele frequencies achieved. Of particular importance, we show that whenever Medea spreads, the non-Medea genotype is driven out of the population, and we estimate the number of generations required to achieve this goal for Medea elements with different fitness costs and male-only introduction frequencies. Finally, we characterize two contexts in which Medea elements with fitness costs drive the non-Medea allele from the population: an autosomal element in which not all Medea-bearing progeny of a Medea-bearing mother survive, and an X-linked element in species in which X/Y individuals are male. Our results suggest that Medea elements can drive population replacement under a wide range of conditions.

Ward, Catherine M.; Su, Jessica T.; Huang, Yunxin; Lloyd, Alun L.; Gould, Fred; Hay, Bruce A.

2013-01-01

272

Heteroplasmy of mouse mtDNA is genetically unstable and results in altered behavior and cognition.  

PubMed

Maternal inheritance of mtDNA is the rule in most animals, but the reasons for this pattern remain unclear. To investigate the consequence of overriding uniparental inheritance, we generated mice containing an admixture (heteroplasmy) of NZB and 129S6 mtDNAs in the presence of a congenic C57BL/6J nuclear background. Analysis of the segregation of the two mtDNAs across subsequent maternal generations revealed that proportion of NZB mtDNA was preferentially reduced. Ultimately, this segregation process produced NZB-129 heteroplasmic mice and their NZB or 129 mtDNA homoplasmic counterparts. Phenotypic comparison of these three mtDNA lines demonstrated that the NZB-129 heteroplasmic mice, but neither homoplasmic counterpart, had reduced activity, food intake, respiratory exchange ratio; accentuated stress response; and cognitive impairment. Therefore, admixture of two normal but different mouse mtDNAs can be genetically unstable and can produce adverse physiological effects, factors that may explain the advantage of uniparental inheritance of mtDNA. PMID:23063123

Sharpley, Mark S; Marciniak, Christine; Eckel-Mahan, Kristin; McManus, Meagan; Crimi, Marco; Waymire, Katrina; Lin, Chun Shi; Masubuchi, Satoru; Friend, Nicole; Koike, Maya; Chalkia, Dimitra; MacGregor, Grant; Sassone-Corsi, Paolo; Wallace, Douglas C

2012-10-12

273

Detection of ultrastructural changes in genetically altered and exercised skeletal muscle using PS-OCT  

NASA Astrophysics Data System (ADS)

Birefringence of skeletal muscle has been associated with the ultrastructure of individual sarcomeres, specifically the arrangement of A-bands corresponding to the thick myosin filaments. Murine skeletal muscle (gastrocnemius) was imaged with a fiber-based PS-OCT imaging system to determine the level of birefringence present in the tissue under various conditions. In addition to muscle controls from wild-type mice, muscle from abnormal mice included: genetically-modified (mdx) mice which model human muscular dystrophy, transgenic mice exhibiting an overexpression of integrin (?7?1), and transgenic integrin (?7?1)knockout mice. Comparisons were also made between rested and exercised muscles to determine the effects of exercise on muscle birefringence for each of these normal and abnormal conditions. The PS-OCT images revealed that the presence of birefringence was similar in the rested muscle with dystrophy-like features (i.e., lacking the structural protein dystrophin - mdx) and in the integrin (?7?1)knockout muscle when compared to the normal (wild-type) control. However, exercising these abnormal muscle tissues drastically reduced the presence of birefringence detected by the PS-OCT system. The muscle exhibiting an overexpression of integrin (?7?1) remained heavily birefringent before and after exercise, similar to the normal (wild-type) muscle. These results suggest that there is a distinct relationship between the degree of birefringence detected using PS-OCT and the sarcomeric ultrastructure present within skeletal muscle.

Pasquesi, James J.; Schlachter, Simon C.; Boppart, Marni D.; Chaney, Eric; Kaufman, Stephen J.; Boppart, Stephen A.

2006-03-01

274

Prenatal genetic testing: an investigation of determining factors affecting the decision-making process.  

PubMed

Despite the increase in popularity of prenatal genetic testing, relatively little is known about the role psychological factors play in the decision-making process. In this analogue study, a sample of Italian female university students was used to investigate determining factors that predict the intention of undergoing prenatal genetic testing. Structural Equation Modelling was used to describe the dynamic interplay between knowledge, beliefs, attitudes and health-related behaviour such as prenatal genetic testing. Following the Theory of Reasoned Action, three dimensions predicted the intention to undergo prenatal genetic testing: the need for more scientific information, a positive attitude towards genetic testing, and the inclination to terminate pregnancy after receiving a positive test result. Results showed that less religious women tended to be more in favour of prenatal tests and in undertaking such tests. This preliminary study provides genetic counsellors and policy makers with a clearer picture of their clients' motives and attitudes behind the decision-making process of prenatal genetic testing, contributing to improving both the communication process between counsellors and their clients and the organization of genetic services. PMID:22477148

Pivetti, Monica; Melotti, Giannino

2012-04-03

275

Responsiveness to sucrose affects tactile and olfactory learning in preforaging honey bees of two genetic strains  

Microsoft Academic Search

Using sucrose solution as reward, we conditioned preforaging honey bees of two genetic strains to tactile stimuli or to odours. Acquisition, extinction of conditioned responses and discrimination between the conditioned stimuli and alternative tactile or olfactory stimuli were measured. Bees of the two genetic strains were selected for their foraging behaviour. In addition, they differ in their responsiveness to sucrose.

Ricarda Scheiner; Robert E Page; Joachim Erber

2001-01-01

276

Genetic basis of altered central tolerance and autoimmune diseases: a lesson from AIRE mutations.  

PubMed

The thymus is a specialized organ that provides an inductive environment for the development of T cells from multipotent hematopoietic progenitors. Self-nonself discrimination plays a key role in inducing a productive immunity and in preventing autoimmune reactions. Tolerance represents a state of immunologic nonresponsiveness in the presence of a particular antigen. The immune system becomes tolerant to self-antigens through the two main processes, central and peripheral tolerance. Central tolerance takes place within the thymus and represents the mechanism by which T cells binding with high avidity self-antigens, which are potentially autoreactive, are eliminated through so-called negative selection. This process is mostly mediated by medullary thymic epithelia cells (mTECs) and medullary dendritic cells (DCs). A remarkable event in the process is the expression of tissue-specific antigens (TSA) by mTECs driven by the transcription factor autoimmune regulator (AIRE). Mutations in this gene result in autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), a rare autosomal recessive disease (OMIM 240300). Thus far, this syndrome is the paradigm of a genetically determined failure of central tolerance and autoimmunty. Patients with APECED have a variable pattern of autoimmune reactions, involving different endocrine and nonendocrine organs. However, although APECED is a monogenic disorder, it is characterized by a wide variability of the clinical expression, thus implying a further role for disease-modifying genes and environmental factors in the pathogenesis. Studies on this polyreactive autoimmune syndrome contributed enormously to unraveling several issues of the molecular basis of autoimmunity. This review focuses on the developmental, functional, and molecular events governing central tolerance and on the clinical implication of its failure. PMID:23083345

Capalbo, Donatella; Giardino, Giuliana; Martino, Lucia De; Palamaro, Loredana; Romano, Rosa; Gallo, Vera; Cirillo, Emilia; Salerno, Mariacarolina; Pignata, Claudio

2012-10-01

277

Altering Trehalose-6-Phosphate Content in Transgenic Potato Tubers Affects Tuber Growth and Alters Responsiveness to Hormones during Sprouting1[C][W  

PubMed Central

Trehalose-6-phosphate (T6P) is a signaling metabolite that regulates carbon metabolism, developmental processes, and growth in plants. In Arabidopsis (Arabidopsis thaliana), T6P signaling is, at least in part, mediated through inhibition of the SNF1-related protein kinase SnRK1. To investigate the role of T6P signaling in a heterotrophic, starch-accumulating storage organ, transgenic potato (Solanum tuberosum) plants with altered T6P levels specifically in their tubers were generated. Transgenic lines with elevated T6P levels (B33-TPS, expressing Escherichia coli osmoregulatory trehalose synthesis A [OtsA], which encodes a T6P synthase) displayed reduced starch content, decreased ATP contents, and increased respiration rate diagnostic for high metabolic activity. On the other hand, lines with significantly reduced T6P (B33-TPP, expressing E. coli OtsB, which encodes a T6P phosphatase) showed accumulation of soluble carbohydrates, hexose phosphates, and ATP, no change in starch when calculated on a fresh weight basis, and a strongly reduced tuber yield. [14C]Glucose feeding to transgenic tubers indicated that carbon partitioning between starch and soluble carbohydrates was not altered. Transcriptional profiling of B33-TPP tubers revealed that target genes of SnRK1 were strongly up-regulated and that T6P inhibited potato tuber SnRK1 activity in vitro. Among the SnRK1 target genes in B33-TPP tubers, those involved in the promotion of cell proliferation and growth were down-regulated, while an inhibitor of cell cycle progression was up-regulated. T6P-accumulating tubers were strongly delayed in sprouting, while those with reduced T6P sprouted earlier than the wild type. Early sprouting of B33-TPP tubers correlated with a reduced abscisic acid content. Collectively, our data indicate that T6P plays an important role for potato tuber growth.

Debast, Stefan; Nunes-Nesi, Adriano; Hajirezaei, Mohammad R.; Hofmann, Jorg; Sonnewald, Uwe; Fernie, Alisdair R.; Bornke, Frederik

2011-01-01

278

ALTERED SENSITIVITY OF THE MOUSE FETUS TO IMPAIRED PROSTATIC BUD FORMATION BY DIOXIN: INFLUENCE OF GENETIC BACKGROUND AND NULL EXPRESSION OF TGF-ALFA AND EGF  

EPA Science Inventory

Altered sensitivity of the mouse fetus to impaired prostatic bud formation by dioxin: Influence of genetic background and null expression of TGF and EGF. Rasmussen, N.T., Lin T-M., Fenton, S.E., Abbott, B.D. and R.E. Peterson. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)...

279

Genetic variation in FOXP2 alters grey matter concentrations in schizophrenia patients.  

PubMed

FOXP2, the first gene known to be involved in the development of speech and language, can be considered to be, a priori, a candidate gene in schizophrenia, given the mounting evidence that the underlying core deficit in this disease could be a failure of structures relevant to normal language processing. To investigate the potential link between grey matter concentration (GMC) changes in patients with schizophrenia and the FOXP2 rs2396753 polymorphism previously reported to be associated with hallucinations in schizophrenia, we analysed high-resolution anatomical magnetic resonance images of 40 genotyped patients with schizophrenia and 36 healthy controls, using optimised voxel-based morphometry (VBM). Here we show that the common SNP rs2396753 (C>A) gene variant of the FOXP2 gene has significant effects on GMC in patients with schizophrenia, within regions of the brain known to be affected by this disease. Our data suggest that GMC reductions in schizophrenia may be driven by C allele carriers of the FOXP2 gene variant. PMID:21334420

Španiel, Filip; Horá?ek, Ji?í; Tint?ra, Jaroslav; Ibrahim, Ibrahim; Novák, Tomáš; ?ermák, Jan; Klírová, Monika; Höschl, Cyril

2011-02-18

280

A Mutation on Influenza C Virus M1 Protein Affects Virion Morphology by Altering the Membrane Affinity of the Protein  

Microsoft Academic Search

Reverse genetics has been documented for influenza A, B, and Thogoto viruses belonging to the family Orthomyxoviridae. We report here the reverse genetics of influenza C virus, another member of this family. The seven viral RNA (vRNA) segments of C\\/Ann Arbor\\/1\\/50 were expressed in 293T cells from cloned cDNAs, together with nine influenza C virus proteins. At 48 h posttransfection,

Yasushi Muraki; Toshio Murata; Emi Takashita; Yoko Matsuzaki; Kanetsu Sugawara; Seiji Hongo

2007-01-01

281

A genome screen of systemic lupus erythematosus using affected-relative-pair linkage analysis with covariates demonstrates genetic heterogeneity.  

PubMed

Systemic lupus erythematosus (SLE) appears to be the consequence of complex genetics and of only partly understood environmental contributions. Previous work by ourselves and by others has established genetic effects on 1q, 2q, 4p, 6p, and 16p using SLE as the phenotype. However, individual SLE affecteds are extraordinarily different from one another by clinical and laboratory measures. This variation may have a genetic basis; if so, it is advantageous to incorporate measures of between-family clinical variability as covariates in a genetic linkage analysis of affected relative pairs (ARPs) to allow for locus heterogeneity. This approach was applied to genome scan marker data from 160 pedigrees multiplex for SLE and containing 202 ARPs. Because the number of potential covariates was large, we used both ad hoc methods and formal principal components analysis to construct four composite covariates using the SLE classification criteria plus age of onset, ethnicity, and sex. Linkage analysis without covariates has detected evidence for linkage at 1q22-24, 2q37, 4p16, 12p12-11, and 17p13. Linkage analysis with these covariates uncovered linkage at 13p11, 17q11-25, and 20q12 and greatly improved evidence for linkage at 1q22-24, 2q37, 12p12-11, and 17p13. Follow-up analysis identified the original variables contributing to locus heterogeneity in each of these locations. In conclusion, allowing for locus heterogeneity through the incorporation of covariates in linkage analysis is a useful way to dissect the genetic contributions to SLE and uncover new genetic effects. PMID:12215896

Olson, J M; Song, Y; Dudek, D M; Moser, K L; Kelly, J A; Bruner, G R; Downing, K J; Berry, C K; James, J A; Harley, J B

2002-10-01

282

Semi-Automatic Classification of Skeletal Morphology in Genetically Altered Mice Using Flat-Panel Volume Computed Tomography  

PubMed Central

Rapid progress in exploring the human and mouse genome has resulted in the generation of a multitude of mouse models to study gene functions in their biological context. However, effective screening methods that allow rapid noninvasive phenotyping of transgenic and knockout mice are still lacking. To identify murine models with bone alterations in vivo, we used flat-panel volume computed tomography (fpVCT) for high-resolution 3-D imaging and developed an algorithm with a computational intelligence system. First, we tested the accuracy and reliability of this approach by imaging discoidin domain receptor 2- (DDR2-) deficient mice, which display distinct skull abnormalities as shown by comparative landmark-based analysis. High-contrast fpVCT data of the skull with 200 ?m isotropic resolution and 8-s scan time allowed segmentation and computation of significant shape features as well as visualization of morphological differences. The application of a trained artificial neuronal network to these datasets permitted a semi-automatic and highly accurate phenotype classification of DDR2-deficient compared to C57BL/6 wild-type mice. Even heterozygous DDR2 mice with only subtle phenotypic alterations were correctly determined by fpVCT imaging and identified as a new class. In addition, we successfully applied the algorithm to classify knockout mice lacking the DDR1 gene with no apparent skull deformities. Thus, this new method seems to be a potential tool to identify novel mouse phenotypes with skull changes from transgenic and knockout mice on the basis of random mutagenesis as well as from genetic models. However for this purpose, new neuronal networks have to be created and trained. In summary, the combination of fpVCT images with artificial neuronal networks provides a reliable, novel method for rapid, cost-effective, and noninvasive primary screening tool to detect skeletal phenotypes in mice.

Dullin, Christian; Missbach-Guentner, Jeannine; Vogel, Wolfgang F; Grabbe, Eckhardt; Alves, Frauke

2007-01-01

283

Pleiotropy of Segregating Genetic Variants that Affect Honey Bee Worker Life Expectancy  

PubMed Central

In contrast to many other complex traits, the natural genetic architecture of life expectancy has not been intensely studied, particularly in non-model organisms, such as the honey bee (Apis mellifera L.). Multiple factors that determine honey bee worker lifespan have been identified and genetic analyses have been performed on some of those traits. Several of the traits are included in a suite of correlated traits that form the pollen hoarding syndrome, which was named after the behavior to store surplus pollen in the nest and is tied to social evolution. Here, seven quantitative trait loci that had previously been identified for their effects on different aspects of the pollen hoarding syndrome were studied for their genetic influence on the survival of adult honey bee workers. To gain a more comprehensive understanding of the genetic architecture of worker longevity, a panel of 280 additional SNP markers distributed across the genome was also tested. Allelic distributions were compared between young and old bees in two backcross populations of the bi-directionally selected high- and low-pollen hoarding strain. Our results suggest a pleiotropic effect of at least one of the behavioral quantitative trait loci on worker longevity and one significant and several other putative genetic effects in other genomic regions. At least one locus showed evidence for strong antagonistic pleiotropy and several others suggested genetic factors that influence pre-emergence survival of worker honey bees. Thus, the predicted association between worker lifespan and the pollen hoarding syndrome was supported at the genetic level and the magnitude of the identified effects also strengthened the view that naturally segregating genetic variation can have major effects on age-specific survival probability in the wild.

Dixon, Luke R.; McQuage, Michelle R.; Lonon, Ellen J.; Buehler, Dominique; Seck, Oumar; Rueppell, Olav

2012-01-01

284

Spinocerebellar Ataxia: Patient and Health Professional Perspectives on Whether and How Patents Affect Access to Clinical Genetic Testing  

PubMed Central

Genetic testing for spinocerebellar ataxia (SCA) is used in diagnosis of rare movement disorders. Such testing generally does not affect treatment, but confirmation of mutations in a known gene can confirm diagnosis and end an often years-long quest for the cause of distressing and disabling symptoms. Through interviews and a web forum hosted by the National Ataxia Foundation, patients and health professionals related their experiences with patents’ impact on access to genetic testing for SCA. In the United States, Athena Diagnostics holds either a patent or an exclusive license to a patent in the case of 6 SCA variants (SCA1-3 & 6-8) and two other hereditary ataxias (Friedreich’s Ataxia and Early Onset Ataxia). Athena has enforced its exclusive rights to SCA-related patents by sending cease and desist letters to multiple laboratories offering genetic testing for inherited neurological conditions, including SCA. Roughly half of web forum respondents had decided not to get genetic tests. Price, coverage and reimbursement by insurers and health plans, and fear of genetic discrimination were the main reasons cited for deciding not to get tested. Price was cited as an access concern by the physicians, and as sole US provider, coverage and reimbursement depend on having payment agreements between Athena and payers. In cases where payers do not reimburse, the patient is responsible for payment, although some patients can apply to the voluntary Athena Access and Patient Protection Programs offered by the company.

Powell, Ashton; Chandrasekharan, Subhashini; Cook-Deegan, Robert

2011-01-01

285

How do population genetic parameters affect germination of the heterocarpic species Atriplex tatarica (Amaranthaceae)?  

PubMed Central

Background and Aims The heterocarpic species Atriplex tatarica produces two types of seeds. In this study, how basic population genetic parameters correlate with seed germinability under various experimental conditions was tested. Methods Population genetic diversity was ascertained in eight populations of A. tatarica by assessing patterns of variation at nine allozyme loci. Germinability of both seed types from all sampled populations was determined by a common laboratory experiment under different salinity levels. Basic population genetic parameters, i.e. percentage of polymorphic loci, average number of alleles per locus and observed heterozygosity were correlated with observed population germination characteristics. Key Results Atriplex tatarica possesses a remarkable heterocarpy, i.e. one type of seed is non-dormant and the other shows different dormancy levels in relation to experimental conditions. Significant negative correlations have been detected between germination of both seed types and the coefficient of inbreeding, and a significant negative correlation between germination of dormant seeds and other population genetic parameters, i.e. percentage of polymorphic loci and average number of alleles per polymorphic locus. Moreover, populations from the region characterized by a shorter growing season manifested higher germinability, i.e. had lower dormancy, than those from the lower-latitude one. Conclusions In general, germination of non-dormant seeds is probably not under strong genetic control. Hence, they germinate as soon as conditions are favourable, thus ensuring survival in the short term, but populations risk local extinction if conditions become adverse (i.e. a high-risk strategy). In contrast, germination of the dormant type of seeds is under stronger genetic control and is significantly correlated with basic population genetic parameters. These seeds ensure long-term reproduction and survival in the field by protracted germination, albeit in low quantities (i.e. A. tatarica also adopts a low-risk strategy).

Kochankova, Jana; Mandak, Bohumil

2009-01-01

286

Genetic low nephron number hypertension is associated with altered expression of osteopontin and CD44 during nephrogenesis*.  

PubMed

Abstract Aims: The study set out to investigate whether the osteopontin (OPN)-CD44-integrin-receptor-system is differently regulated during nephrogenesis in inborn nephron deficit, a major determinant of human primary hypertension and cardiovascular disease in adult life. Methods: We compared a genetic rat model with an inherited nephron deficit, the Munich-Wistar-Froemter rat (MWF), to normotensive Wistar rats during nephrogenesis at day 19 of fetal development (E19) and at postpartal day 7 (D7). Results: Renal OPN mRNA (-75%, P<0.05) and protein expression (-38%, P<0.05) were strongly decreased at E19 in MWF compared to Wistar. Renal mRNA-expression of CD44 was increased at E19 in MWF (+271%, P<0.05). At D7, renal OPN protein expression was increased (+115%, P<0.05) and renal mRNA-expression of CD44 remained elevated compared to Wistar control (+127%, P<0.05). Conclusions: Altered fetal expression of the OPN-CD44-integrin-receptor-system in the MWF model points to a possible role in low nephron number hypertension and cardiovascular disease. PMID:23241663

Freese, Anne; Wehland, Markus; Freese, Florian; Bamberg, Christian; Kreutz, Reinhold; Rothermund, Lars

2013-05-01

287

An Experimental Investigation of Parameters Affecting Oil Recovery Efficiency Alteration during a Microbially Aided Water Flooding Process  

Microsoft Academic Search

In order to evaluate the potential of microbial recovery in the Iranian Maroon oilfield, laboratory core flood tests were designed and conducted. The effect of biosurfactant production on the recovery of crude oil during waterflooding and the effect of bioproducts on wettability alteration of the cores was investigated. Three different kinds of microbes in two different kinds of growth media

P. Heidari; A. Kordestany; M. H. Ghazanfari

2011-01-01

288

Human Immunodeficiency Virus Type 1 Gag p24 Alters the Composition of Immunoproteasomes and Affects Antigen Presentation  

Microsoft Academic Search

Proteasomes are the major source of proteases responsible for the generation of peptides bound to major histocompatibility complex class I molecules. Antigens, adjuvants, and cytokines can modulate the composition and enzymatic activity of proteasomes and thus alter the epitopes generated. In the present study, we examined the effect of human immunodeficiency virus type 1 (HIV-1) p24 on proteasomes from a

Nicholas J. Steers; Kristina K. Peachman; Sasha R. McClain; Carl R. Alving; Mangala Rao

2009-01-01

289

Altered cytokinin metabolism affects cytokinin, auxin, and abscisic acid contents in leaves and chloroplasts, and chloroplast ultrastructure in transgenic tobacco  

Microsoft Academic Search

Cytokinins (CKs) are involved in the regulation of plant development including plastid differentiation and func- tion. Partial location of CK biosynthetic pathways in plastids suggests the importance of CKs for chloroplast development. The impact of genetically modified CK metabolism on endogenous CK, indole-3-acetic acid, and abscisic acid contents in leaves and isolated intact chloroplasts of Nicotiana tabacum was deter- mined

Lenka Polanska ´; Anna Vicankova ´; Marie Novakova ´; J. Malbeck; Petre I. Dobrev; Bretislav Brzobohaty; Radomira Vankova ´; Ivana Machackova

2006-01-01

290

Plant traits correlated with generation time directly affect inbreeding depression and mating system and indirectly genetic structure  

PubMed Central

Background Understanding the mechanisms that control species genetic structure has always been a major objective in evolutionary studies. The association between genetic structure and species attributes has received special attention. As species attributes are highly taxonomically constrained, phylogenetically controlled methods are necessary to infer causal relationships. In plants, a previous study controlling for phylogenetic signal has demonstrated that Wright's FST, a measure of genetic differentiation among populations, is best predicted by the mating system (outcrossing, mixed-mating or selfing) and that plant traits such as perenniality and growth form have only an indirect influence on FST via their association with the mating system. The objective of this study is to further outline the determinants of plant genetic structure by distinguishing the effects of mating system on gene flow and on genetic drift. The association of biparental inbreeding and inbreeding depression with population genetic structure, mating system and plant traits are also investigated. Results Based on data from 263 plant species for which estimates of FST, inbreeding (FIS) and outcrossing rate (tm) are available, we confirm that mating system is the main influencing factor of FST. Moreover, using an alternative measure of FST unaffected by the impact of inbreeding on effective population size, we show that the influence of tm on FST is due to its impact on gene flow (reduced pollen flow under selfing) and on genetic drift (higher drift under selfing due to inbreeding). Plant traits, in particular perenniality, influence FST mostly via their effect on the mating system but also via their association with the magnitude of selection against inbred individuals: the mean inbreeding depression increases from short-lived herbaceous to long-lived herbaceous and then to woody species. The influence of perenniality on mating system does not seem to be related to differences in stature, as proposed earlier, but rather to differences in generation time. Conclusion Plant traits correlated with generation time affect both inbreeding depression and mating system. These in turn modify genetic drift and gene flow and ultimately genetic structure.

Duminil, Jerome; Hardy, Olivier J; Petit, Remy J

2009-01-01

291

Alterations in lignin content and phenylpropanoids pathway in date palm (Phoenix dactylifera L.) tissues affected by brittle leaf disease.  

PubMed

Brittle leaf disease or Maladie de la Feuille Cassante (MFC) is a lethal disorder of date palm that has assumed epidemic proportions in the oases of Tunisia and Algeria. No pathogen could ever be associated with the disease, while leaflets of affected palms have been previously shown to be deficient in manganese. The work reported here aims to understand the biochemical basis of the date palm response to this disorder. Since the typical disease symptom is the leaf fragility, we have investigated lignin content in leaves and roots. Strong decrease in total lignin content was observed in affected leaves, while lignin content increased in affected roots. Histochemical analyses showed hyperlignification thicker suberin layer in roots cortical cells. The phenylpropanoids pathway was also disrupted in leaves and roots, cinnamoyl-CoA reductase and cinnamyl-alcohol dehydrogenase gene expression was affected by the disease which severely affects the cell wall integrity. PMID:23987806

Saidi, Mohammed Najib; Bouaziz, Donia; Hammami, Ines; Namsi, Ahmed; Drira, Noureddine; Gargouri-Bouzid, Radhia

2013-06-21

292

Genetic modifiers interact with Cpefat to affect body weight, adiposity, and hyperglycemia  

Microsoft Academic Search

Obesity and Type II diabetes are complex diseases in the human population. The existence of a large number of contributing loci and gene-gene as well as gene-environment interactions make it difficult to identify the disease genes underlying these complex traits. In mouse models of obesity and Type II diabetes such as the murine fat mutation, genetic crosses can be used

Gayle B. Collin; Terry P. Maddatu; Saunak Sen; Jurgen K. Naggert

2005-01-01

293

Parental Discipline and Affection and Children's Prosocial Behavior: Genetic and Environmental Links  

Microsoft Academic Search

The authors investigated genetic and environmental contributions to the relationships between children's (N = 9,319 twin pairs) prosocial behavior and parental positivity and negativity toward them. Children's prosocial behavior was rated by parents at ages 3, 4, and 7 and by teachers at age 7. At each age, parents described their feelings and discipline toward each twin. Parental positivity was

Ariel Knafo; Robert Plomin

2006-01-01

294

Genetic variation in human NPY expression affects stress response and emotion  

Microsoft Academic Search

Understanding inter-individual differences in stress response requires the explanation of genetic influences at multiple phenotypic levels, including complex behaviours and the metabolic responses of brain regions to emotional stimuli. Neuropeptide Y (NPY) is anxiolytic and its release is induced by stress. NPY is abundantly expressed in regions of the limbic system that are implicated in arousal and in the assignment

Zhifeng Zhou; Guanshan Zhu; Ahmad R. Hariri; Mary-Anne Enoch; David Scott; Rajita Sinha; Matti Virkkunen; Deborah C. Mash; Robert H. Lipsky; Xian-Zhang Hu; Colin A. Hodgkinson; Ke Xu; Beata Buzas; Qiaoping Yuan; Pei-Hong Shen; Robert E. Ferrell; Stephen B. Manuck; Sarah M. Brown; Richard L. Hauger; Christian S. Stohler; Jon-Kar Zubieta; David Goldman

2008-01-01

295

Environmental, Management, and Genetic Factors Affecting Semen Production in Holstein Bulls  

Microsoft Academic Search

The objective of this study was to evaluate the importance of environment, management, physiologi- cal status, and genetics on semen quality (volume of the ejaculate, sperm concentration, sperm motility, number of sperm, and number of motile spermatozoa per ejaculate) of Canadian Holstein bulls. For this purpose, semen production data from 198 bulls were analyzed using mixed linear models. Young bulls

M. Mathevon; M. M. Buhr; J. C. M. Dekkers

1998-01-01

296

Genetic variation in defense chemistry in wild cabbages affects herbivores and their endoparasitoids  

Microsoft Academic Search

Populations of wild Brassica oleracea L. grow naturally along the Atlantic coastlines of the United Kingdom and France. Over a very small spatial scale (i.e., <15 km) these populations differ in the expression of the defensive compounds, glucosinolates (GS). Thus far, very few studies have examined interactions between genetically distinct populations of a wild plant species and associated consumers in

Rieta Gols; R. Wagenaar; Tibor Bukovinszky; Nicole M. van Dam; Marcel Dicke; James M. Bullock; Jeffrey A. Harvey

2008-01-01

297

Genetically-based plant resistance traits affect arthropods, fungi, and birds  

Microsoft Academic Search

We examine how the distribution of a leafgalling aphid (Pemphigus betae) affects other species associated with natural stands of hybrid cottonwoods (Populus angustifolia x P. fremontii). Aphid transfers on common-garden clones and RFLP analysis show that resistance to aphids in cottonwoods is affected by plant genotype. Because susceptible trees typically support thousands of galls, while adjacent resistant trees have few

Lara Lee Dickson; Thomas G. Whitham

1996-01-01

298

Uncertainty management and communication preferences related to genetic relativism among families affected by down syndrome, Marfan syndrome, and neurofibromatosis.  

PubMed

Genes hold opportunities for us to look backward and forward in family health and disease incidence. Our beliefs about genes' roles in health form around frameworks relating to personal control, and the influence of social networks and/or religious faith on genetic expression in health. These genetic relativistic frameworks were found to predict levels of illness uncertainty among 541 diagnosed adults and family members affected by neurofibromatosis, Down syndrome, and Marfan syndrome. Participants were recruited and surveyed about their expectations and preferences for communicating about their respective disorder, with illness uncertainty found to predict the desire to communicate about the condition and to manage related uncertainty. The desire to manage uncertainty in ways that foster control and hope partially mediated the relationship between illness uncertainty and communication preferences. Negative feelings about the condition, which were stronger for affected participants than for family members, related to illness uncertainty, the desire to manage uncertainty, and communication preferences, mediating the relationship between illness uncertainty and uncertainty management. Findings contribute to research in illness uncertainty management and have pragmatic implications for the design of counseling and educational materials associated with the genetic conditions considered in this research. PMID:22168461

Parrott, Roxanne; Peters, Kathryn F; Traeder, Tara

2011-12-14

299

Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral  

Microsoft Academic Search

In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone.Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a

E. P. Paschalis; D. N. Tatakis; S. Robins; P. Fratzl; I. Manjubala; R. Zoehrer; S. Gamsjaeger; B. Buchinger; A. Roschger; R. Phipps; A. L. Boskey; E. Dall'Ara; P. Varga; P. Zysset; K. Klaushofer; P. Roschger

300

Germline Genetic Variants Disturbing the Let-7/LIN28 Double-Negative Feedback Loop Alter Breast Cancer Susceptibility  

PubMed Central

Previous studies have shown that let-7 can repress the post-transcriptional translation of LIN28, and LIN28 in turn could block the maturation of let-7, forming a double-negative feedback loop. In this study, we investigated the effect of germline genetic variants on regulation of the homeostasis of the let-7/LIN28 loop and breast cancer risk. We initially demonstrated that the T/C variants of rs3811463, a single nucleotide polymorphism (SNP) located near the let-7 binding site in LIN28, could lead to differential regulation of LIN28 by let-7. Specifically, the C allele of rs3811463 weakened let-7–induced repression of LIN28 mRNA, resulting in increased production of LIN28 protein, which could in turn down-regulate the level of mature let-7. This effect was then validated at the tissue level in that the normal breast tissue of individuals with the rs3811463-TC genotype expressed significantly lower levels of let-7 and higher levels of LIN28 protein than those individuals with the rs3811463-TT genotype. Because previous in vitro and ex vivo experiments have consistently suggested that LIN28 could promote cellular transformation, we then systematically evaluated the relationship between rs3811463 as well as other common LIN28 SNPs and the risk of breast cancer in a stepwise manner. The first hospital-based association study (n?=?2,300) demonstrated that two SNPs were significantly associated with breast cancer risk, one of which was rs3811463, while the other was rs6697410. The C allele of the rs3811463 SNP corresponded to an increased risk of breast cancer with an odds ratio (OR) of 1.25 (P?=?0.0091), which was successfully replicated in a second independent study (n?=?1,156) with community-based controls. The combined P-value of the two studies was 8.0×10?5. Taken together, our study demonstrates that host genetic variants could disturb the regulation of the let-7/LIN28 double-negative feedback loop and alter breast cancer risk.

Fan, Lei; Li, Ji-Yu; Yang, Chen; Huang, A-Ji; Shao, Zhi-Ming

2011-01-01

301

Oxidative stability of purified canola oil triacylglycerols with altered fatty acid compositions as affected by triacylglycerol composition and structure  

Microsoft Academic Search

Canola oil triacylglycerols from genetically modified canola lines (InterMountain Canola Co., Cinnaminson, NJ) have been evaluated\\u000a for their photooxidative and autoxidative stabilities, as influenced by their fatty acid compositions and their triacylglycerol\\u000a compositions and structures. Purified canola oil triacylglycerols were oxidized in duplicate in fluorescent light at 25°C\\u000a and in the dark at 60°C under oxygen, and their oxidative deterioration

W. E. Neff; T. L. Mounts; W. M. Rinsch; H. Konishi; M. A. El-Agaimy

1994-01-01

302

Genetic changes from artificial propagation of Pacific salmon affect the productivity and viability of supplemented populations  

USGS Publications Warehouse

Although several studies have shown genetic differences between hatchery and wild anadromous Pacific salmon (Oncorhynchus spp.), none has provided compelling evidence that artificial propagation poses a genetic threat to conservation of naturally spawning populations. When the published studies and three studies in progress are considered collectively, however, they provide strong evidence that the fitness for natural spawning and rearing can be rapidly and substantially reduced by artificial propagation. This issue takes on great importance in the Pacific Northwest where supplementation of wild salmon populations with hatchery fish has been identified as an important tool for restoring these populations. Recognition of negative aspects may lead to restricted use of supplementation, and better conservation, better evaluation, and greater benefits when supplementation is used.

Reisenbichler, R. R.; Rubin, S. P.

1999-01-01

303

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.  

PubMed

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection. PMID:21051598

Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J; Telenti, Amalio; de Bakker, Paul I W; Walker, Bruce D; Ripke, Stephan; Brumme, Chanson J; Pulit, Sara L; Carrington, Mary; Kadie, Carl M; Carlson, Jonathan M; Heckerman, David; Graham, Robert R; Plenge, Robert M; Deeks, Steven G; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noël P; Guiducci, Candace; Gupta, Namrata; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L; Vine, Seanna; Addo, Marylyn M; Allen, Todd M; Altfeld, Marcus; Henn, Matthew R; Le Gall, Sylvie; Streeck, Hendrik; Haas, David W; Kuritzkes, Daniel R; Robbins, Gregory K; Shafer, Robert W; Gulick, Roy M; Shikuma, Cecilia M; Haubrich, Richard; Riddler, Sharon; Sax, Paul E; Daar, Eric S; Ribaudo, Heather J; Agan, Brian; Agarwal, Shanu; Ahern, Richard L; Allen, Brady L; Altidor, Sherly; Altschuler, Eric L; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C; Benson, Anne M; Berger, Judith; Bernard, Nicole F; Bernard, Annette M; Birch, Christopher; Bodner, Stanley J; Bolan, Robert K; Boudreaux, Emilie T; Bradley, Meg; Braun, James F; Brndjar, Jon E; Brown, Stephen J; Brown, Katherine; Brown, Sheldon T; Burack, Jedidiah; Bush, Larry M; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H; Carmichael, J Kevin; Casey, Kathleen K; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T; Chez, Nancy; Chirch, Lisa M; Cimoch, Paul J; Cohen, Daniel; Cohn, Lillian E; Conway, Brian; Cooper, David A; Cornelson, Brian; Cox, David T; Cristofano, Michael V; Cuchural, George; Czartoski, Julie L; Dahman, Joseph M; Daly, Jennifer S; Davis, Benjamin T; Davis, Kristine; Davod, Sheila M; DeJesus, Edwin; Dietz, Craig A; Dunham, Eleanor; Dunn, Michael E; Ellerin, Todd B; Eron, Joseph J; Fangman, John J W; Farel, Claire E; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A; French, Neel K; Fuchs, Jonathan D; Fuller, Jon D; Gaberman, Jonna; Gallant, Joel E; Gandhi, Rajesh T; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C; Gaultier, Cyril R; Gebre, Wondwoosen; Gilman, Frank D; Gilson, Ian; Goepfert, Paul A; Gottlieb, Michael S; Goulston, Claudia; Groger, Richard K; Gurley, T Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W David; Harrigan, P Richard; Hawkins, Trevor N; Heath, Sonya; Hecht, Frederick M; Henry, W Keith; Hladek, Melissa; Hoffman, Robert P; Horton, James M; Hsu, Ricky K; Huhn, Gregory D; Hunt, Peter; Hupert, Mark J; Illeman, Mark L; Jaeger, Hans; Jellinger, Robert M; John, Mina; Johnson, Jennifer A; Johnson, Kristin L; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C; Kauffman, Carol A; Khanlou, Homayoon; Killian, Robert K; Kim, Arthur Y; Kim, David D; Kinder, Clifford A; Kirchner, Jeffrey T; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P Todd; Kurisu, Wayne; Kwon, Douglas S; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M; Lee, David M; Lee, Jean M L; Lee, Marah J; Lee, Edward T Y; Lemoine, Janice; Levy, Jay A; Llibre, Josep M; Liguori, Michael A; Little, Susan J; Liu, Anne Y; Lopez, Alvaro J; Loutfy, Mono R; Loy, Dawn; Mohammed, Debbie Y; Man, Alan; Mansour, Michael K; Marconi, Vincent C; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N; Martin, Harold L; Mayer, Kenneth Hugh; McElrath, M Juliana; McGhee, Theresa A; McGovern, Barbara H; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X; Menezes, Prema; Mesa, Greg; Metroka, Craig E; Meyer-Olson, Dirk; Miller, Andy O; Montgomery, Kate; Mounzer, Karam C; Nagami, Ellen H; Nagin, Iris; Nahass, Ronald G; Nelson, Margret O; Nielsen, Craig; Norene, David L; O'Connor, David H; Ojikutu, Bisola O; Okulicz, Jason; Oladehin, Olakunle O; Oldfield, Edward C; Olender, Susan A; Ostrowski, Mario; Owen, William F; Pae, Eunice; Parsonnet, Jeffrey; Pavlatos, Andrew M; Perlmutter, Aaron M; Pierce, Michael N; Pincus, Jonathan M; Pisani, Leandro; Price, Lawrence Jay; Proia, Laurie; Prokesch, Richard C; Pujet, Heather Calderon; Ramgopal, Moti; Rathod, Almas; Rausch, Michael; Ravishankar, J; Rhame, Frank S

2010-11-04

304

The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation  

PubMed Central

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA–viral peptide interaction as the major factor modulating durable control of HIV infection.

Pereyra, Florencia; Jia, Xiaoming; McLaren, Paul J.; Telenti, Amalio; de Bakker, Paul I.W.; Walker, Bruce D.; Jia, Xiaoming; McLaren, Paul J.; Ripke, Stephan; Brumme, Chanson J.; Pulit, Sara L.; Telenti, Amalio; Carrington, Mary; Kadie, Carl M.; Carlson, Jonathan M.; Heckerman, David; de Bakker, Paul I.W.; Pereyra, Florencia; de Bakker, Paul I.W.; Graham, Robert R.; Plenge, Robert M.; Deeks, Steven G.; Walker, Bruce D.; Gianniny, Lauren; Crawford, Gabriel; Sullivan, Jordan; Gonzalez, Elena; Davies, Leela; Camargo, Amy; Moore, Jamie M.; Beattie, Nicole; Gupta, Supriya; Crenshaw, Andrew; Burtt, Noel P.; Guiducci, Candace; Gupta, Namrata; Carrington, Mary; Gao, Xiaojiang; Qi, Ying; Yuki, Yuko; Pereyra, Florencia; Piechocka-Trocha, Alicja; Cutrell, Emily; Rosenberg, Rachel; Moss, Kristin L.; Lemay, Paul; O'Leary, Jessica; Schaefer, Todd; Verma, Pranshu; Toth, Ildiko; Block, Brian; Baker, Brett; Rothchild, Alissa; Lian, Jeffrey; Proudfoot, Jacqueline; Alvino, Donna Marie L.; Vine, Seanna; Addo, Marylyn M.; Allen, Todd M.; Altfeld, Marcus; Henn, Matthew R.; Le Gall, Sylvie; Streeck, Hendrik; Walker, Bruce D.; Haas, David W.; Kuritzkes, Daniel R.; Robbins, Gregory K.; Shafer, Robert W.; Gulick, Roy M.; Shikuma, Cecilia M.; Haubrich, Richard; Riddler, Sharon; Sax, Paul E.; Daar, Eric S.; Ribaudo, Heather J.; Agan, Brian; Agarwal, Shanu; Ahern, Richard L.; Allen, Brady L.; Altidor, Sherly; Altschuler, Eric L.; Ambardar, Sujata; Anastos, Kathryn; Anderson, Ben; Anderson, Val; Andrady, Ushan; Antoniskis, Diana; Bangsberg, David; Barbaro, Daniel; Barrie, William; Bartczak, J.; Barton, Simon; Basden, Patricia; Basgoz, Nesli; Bazner, Suzane; Bellos, Nicholaos C.; Benson, Anne M.; Berger, Judith; Bernard, Nicole F.; Bernard, Annette M.; Birch, Christopher; Bodner, Stanley J.; Bolan, Robert K.; Boudreaux, Emilie T.; Bradley, Meg; Braun, James F.; Brndjar, Jon E.; Brown, Stephen J.; Brown, Katherine; Brown, Sheldon T.; Burack, Jedidiah; Bush, Larry M.; Cafaro, Virginia; Campbell, Omobolaji; Campbell, John; Carlson, Robert H.; Carmichael, J. Kevin; Casey, Kathleen K.; Cavacuiti, Chris; Celestin, Gregory; Chambers, Steven T.; Chez, Nancy; Chirch, Lisa M.; Cimoch, Paul J.; Cohen, Daniel; Cohn, Lillian E.; Conway, Brian; Cooper, David A.; Cornelson, Brian; Cox, David T.; Cristofano, Michael V.; Cuchural, George; Czartoski, Julie L.; Dahman, Joseph M.; Daly, Jennifer S.; Davis, Benjamin T.; Davis, Kristine; Davod, Sheila M.; Deeks, Steven G.; DeJesus, Edwin; Dietz, Craig A.; Dunham, Eleanor; Dunn, Michael E.; Ellerin, Todd B.; Eron, Joseph J.; Fangman, John J.W.; Farel, Claire E.; Ferlazzo, Helen; Fidler, Sarah; Fleenor-Ford, Anita; Frankel, Renee; Freedberg, Kenneth A.; French, Neel K.; Fuchs, Jonathan D.; Fuller, Jon D.; Gaberman, Jonna; Gallant, Joel E.; Gandhi, Rajesh T.; Garcia, Efrain; Garmon, Donald; Gathe, Joseph C.; Gaultier, Cyril R.; Gebre, Wondwoosen; Gilman, Frank D.; Gilson, Ian; Goepfert, Paul A.; Gottlieb, Michael S.; Goulston, Claudia; Groger, Richard K.; Gurley, T. Douglas; Haber, Stuart; Hardwicke, Robin; Hardy, W. David; Harrigan, P. Richard; Hawkins, Trevor N.; Heath, Sonya; Hecht, Frederick M.; Henry, W. Keith; Hladek, Melissa; Hoffman, Robert P.; Horton, James M.; Hsu, Ricky K.; Huhn, Gregory D.; Hunt, Peter; Hupert, Mark J.; Illeman, Mark L.; Jaeger, Hans; Jellinger, Robert M.; John, Mina; Johnson, Jennifer A.; Johnson, Kristin L.; Johnson, Heather; Johnson, Kay; Joly, Jennifer; Jordan, Wilbert C.; Kauffman, Carol A.; Khanlou, Homayoon; Killian, Robert K.; Kim, Arthur Y.; Kim, David D.; Kinder, Clifford A.; Kirchner, Jeffrey T.; Kogelman, Laura; Kojic, Erna Milunka; Korthuis, P. Todd; Kurisu, Wayne; Kwon, Douglas S.; LaMar, Melissa; Lampiris, Harry; Lanzafame, Massimiliano; Lederman, Michael M.; Lee, David M.; Lee, Jean M.L.; Lee, Marah J.; Lee, Edward T.Y.; Lemoine, Janice; Levy, Jay A.; Llibre, Josep M.; Liguori, Michael A.; Little, Susan J.; Liu, Anne Y.; Lopez, Alvaro J.; Loutfy, Mono R.; Loy, Dawn; Mohammed, Debbie Y.; Man, Alan; Mansour, Michael K.; Marconi, Vincent C.; Markowitz, Martin; Marques, Rui; Martin, Jeffrey N.; Martin, Harold L.; Mayer, Kenneth Hugh; McElrath, M. Juliana; McGhee, Theresa A.; McGovern, Barbara H.; McGowan, Katherine; McIntyre, Dawn; Mcleod, Gavin X.; Menezes, Prema; Mesa, Greg; Metroka, Craig E.; Meyer-Olson, Dirk; Miller, Andy O.; Montgomery, Kate; Mounzer, Karam C.; Nagami, Ellen H.; Nagin, Iris; Nahass, Ronald G.; Nelson, Margret O.; Nielsen, Craig; Norene, David L.; O'Connor, David H.; Ojikutu, Bisola O.; Okulicz, Jason; Oladehin, Olakunle O.; Oldfield, Edward C.; Olender, Susan A.

2011-01-01

305

The genetic map of Artemisia annua L. identifies loci affecting yield of the antimalarial drug artemisinin.  

PubMed

Artemisinin is a plant natural product produced by Artemisia annua and the active ingredient in the most effective treatment for malaria. Efforts to eradicate malaria are increasing demand for an affordable, high-quality, robust supply of artemisinin. We performed deep sequencing on the transcriptome of A. annua to identify genes and markers for fast-track breeding. Extensive genetic variation enabled us to build a detailed genetic map with nine linkage groups. Replicated field trials resulted in a quantitative trait loci (QTL) map that accounts for a significant amount of the variation in key traits controlling artemisinin yield. Enrichment for positive QTLs in parents of new high-yielding hybrids confirms that the knowledge and tools to convert A. annua into a robust crop are now available. PMID:20075252

Graham, Ian A; Besser, Katrin; Blumer, Susan; Branigan, Caroline A; Czechowski, Tomasz; Elias, Luisa; Guterman, Inna; Harvey, David; Isaac, Peter G; Khan, Awais M; Larson, Tony R; Li, Yi; Pawson, Tanya; Penfield, Teresa; Rae, Anne M; Rathbone, Deborah A; Reid, Sonja; Ross, Joe; Smallwood, Margaret F; Segura, Vincent; Townsend, Theresa; Vyas, Darshna; Winzer, Thilo; Bowles, Dianna

2010-01-15

306

Does recent habitat fragmentation affect the population genetics of a heathland specialist, Andrena fuscipes (Hymenoptera: Andrenidae)?  

Microsoft Academic Search

Habitat fragmentation is believed to be a key threat to biodiversity as it decreases the probability of survival of populations,\\u000a reduces gene flow among populations and increases the possibility of inbreeding and loss of genetic diversity within populations.\\u000a Heathlands represent excellent systems to study fragmentation effects as the spatial and temporal course of fragmentation\\u000a is well documented for these habitats.

Nina Exeler; Anselm Kratochwil; Axel Hochkirch

2010-01-01

307

Habitat fragmentation affects genetic diversity and differentiation of the Yarkand hare  

Microsoft Academic Search

The Yarkand hare, Lepus yarkandensis, is an endemic, endangered species restricted to the Tarim Basin of the Xinjiang Uygur Autonomous Region, China. The Yarkand\\u000a hare is distributed in scattered oases which are physically isolated by the desert. Its natural fragmentation habitat makes\\u000a it an ideal object for studying effect of habitat fragmentation on its genetic structure. To evaluate the effects

Yonghua Wu; Lin Xia; Qian Zhang; Qisen Yang

2010-01-01

308

Genetic variation in the apolipoprotein H (ß2-glycoprotein I) gene affects plasma apolipoprotein H concentrations  

Microsoft Academic Search

Apolipoprotein H (apoH, protein; APOH, gene) is a single chain glycoprotein that exists in plasma both in a free form and in combination with lipoprotein particles. ApoH has been implicated in several physiologic pathways, including lipid metabolism, coagulation, and the production of antiphospholipid antibodies. The wide range of interindividual variation in plasma apoH levels is thought to be under genetic

Haider Mehdi; Christopher E. Aston; Dharambir K. Sanghera; Richard F. Hamman; M. Ilyas Kamboh

1999-01-01

309

Individualizing Pharmacotherapy: Genetic factors and co-prescribed drugs affecting pharmacotherapy  

Microsoft Academic Search

Drug therapies may result in adverse drug reactions or in ineffective therapy. A better prediction which patients will not respond to drug therapy or will develop adverse drug reactions may avoid these events. In this thesis we studied the effect of drug-drug interactions and genetic variation.\\u000aThe exposure to potential life-threatening drug-drug interactions in the elderly general population (? 70

M. L. Becker

2009-01-01

310

A Forward Genetic Strategy Reveals Destabilizing Mutations in the Ebolavirus Glycoprotein That Alter Its Protease Dependence during Cell Entry? †  

PubMed Central

Ebolavirus (EBOV) entry into cells requires proteolytic disassembly of the viral glycoprotein, GP. This proteolytic processing, unusually extensive for an enveloped virus entry protein, is mediated by cysteine cathepsins, a family of endosomal/lysosomal proteases. Previous work has shown that cleavage of GP by cathepsin B (CatB) is specifically required to generate a critical entry intermediate. The functions of this intermediate are not well understood. We used a forward genetic strategy to investigate this CatB-dependent step. Specifically, we generated a replication-competent recombinant vesicular stomatitis virus bearing EBOV GP as its sole entry glycoprotein and used it to select viral mutants resistant to a CatB inhibitor. We obtained mutations at six amino acid positions in GP that independently confer complete resistance. All of the mutations reside at or near the GP1-GP2 intersubunit interface in the membrane-proximal base of the prefusion GP trimer. This region forms a part of the “clamp” that holds the fusion subunit GP2 in its metastable prefusion conformation. Biochemical studies suggest that most of the mutations confer CatB independence not by altering specific cleavage sites in GP but rather by inducing conformational rearrangements in the prefusion GP trimer that dramatically enhance its susceptibility to proteolysis. The remaining mutants did not show the preceding behavior, indicating the existence of multiple mechanisms for acquiring CatB independence during entry. Altogether, our findings suggest that CatB cleavage is required to facilitate the triggering of viral membrane fusion by destabilizing the prefusion conformation of EBOV GP.

Wong, Anthony C.; Sandesara, Rohini G.; Mulherkar, Nirupama; Whelan, Sean P.; Chandran, Kartik

2010-01-01

311

Source population characteristics affect heterosis following genetic rescue of fragmented plant populations.  

PubMed

Understanding the relative importance of heterosis and outbreeding depression over multiple generations is a key question in evolutionary biology and is essential for identifying appropriate genetic sources for population and ecosystem restoration. Here we use 2455 experimental crosses between 12 population pairs of the rare perennial plant Rutidosis leptorrhynchoides (Asteraceae) to investigate the multi-generational (F(1), F(2), F(3)) fitness outcomes of inter-population hybridization. We detected no evidence of outbreeding depression, with inter-population hybrids and backcrosses showing either similar fitness or significant heterosis for fitness components across the three generations. Variation in heterosis among population pairs was best explained by characteristics of the foreign source or home population, and was greatest when the source population was large, with high genetic diversity and low inbreeding, and the home population was small and inbred. Our results indicate that the primary consideration for maximizing progeny fitness following population augmentation or restoration is the use of seed from large, genetically diverse populations. PMID:23173202

Pickup, M; Field, D L; Rowell, D M; Young, A G

2013-01-01

312

Alterations of the retino-cortical conduction in patients affected by classical congenital muscular dystrophy (CI-CMD) with merosin deficiency.  

PubMed

Immunocytochemical analysis of the laminin alpha-2 (merosin) chain in the muscle of patients with Classic Congenital Muscular Dystrophy (Cl-CMD) differentiates the types of the disease associated with a merosin deficit from those that are merosin positive. Patients with Central Nervous System involvement in merosin negative Cl-CMD always present alterations of the white matter at RMI, but usually these are not clinically significant. While ocular malformations (microphthalmia, alterations of the anterior chamber, of the retina, or of the angle and cataract) and damage to the Central Nervous System are described in some subtypes of CMD (Muscle Eye Brain disease, Walker Warburg Syndrome), ocular involvement and retino-cortical conduction in merosin negative Cl-CMD are not well known. This study reports on four patients affected by merosin negative Cl-CMD. All these patients presented important alterations of the white matter associated with ventricular enlargement and, in one case, with pachygyria and micropolygyria. Refraction, visual acuity, ocular motility, anterior segment and fundus were examined. ERG Maximal, Cone and Rod response, VEP transient pattern reversal was carried out as well. Significant alterations at the standard ophthalmologic examination or of the electroretinogram responses were not registered while, in all cases, important modifications in retino cortical conduction (reduction in amplitude, increase in latency, reduction in amplitude on the lateral derivations) were observed, demonstrating involvement of the optic pathway at different levels during the course of this disease. PMID:10946999

Tormene, A P; Trevisan, C; Martinello, F; Riva, C; Pastorello, E

1999-01-01

313

The (15)N isotope effect as a means for correlating phenotypic alterations and affected pathways in a trait anxiety mouse model.  

PubMed

Stable isotope labeling techniques hold great potential for accurate quantitative proteomics comparisons by MS. To investigate the effect of stable isotopes in vivo, we metabolically labeled high anxiety-related behavior (HAB) mice with the heavy nitrogen isotope (15)N. (15)N-labeled HAB mice exhibited behavioral alterations compared to unlabeled ((14)N) HAB mice in their depression-like phenotype. To correlate behavioral alterations with changes on the molecular level, we explored the (15)N isotope effect on the brain proteome by comparing protein expression levels between (15)N-labeled and (14)N HAB mouse brains using quantitative MS. By implementing two complementary in silico pathway analysis approaches, we were able to identify altered networks in (15)N-labeled HAB mice, including major metabolic pathways such as the tricarboxylic acid (TCA) cycle and oxidative phosphorylation. Here, we discuss the affected pathways with regard to their relevance for the behavioral phenotype and critically assess the utility of exploiting the (15)N isotope effect for correlating phenotypic and molecular alterations. PMID:22700377

Filiou, Michaela D; Webhofer, Christian; Gormanns, Philipp; Zhang, Yaoyang; Reckow, Stefan; Bisle, Birgit; Teplytska, Larysa; Frank, Elisabeth; Kessler, Melanie S; Maccarrone, Giuseppina; Landgraf, Rainer; Turck, Christoph W

2012-07-19

314

Antidepressant treatment is associated with epigenetic alterations in the promoter of P11 in a genetic model of depression.  

PubMed

P11 (S100A10) has been associated with the pathophysiology of depression both in human and rodent models. Different types of antidepressants have been shown to increase P11 levels in distinct brain regions and P11 gene therapy was recently proven effective in reversing depressive-like behaviours in mice. However, the molecular mechanisms that govern P11 gene expression in response to antidepressants still remain elusive. In this study we report decreased levels of P11, associated with higher DNA methylation in the promoter region, in the prefrontal cortex of the Flinders Sensitive Line (FSL) genetic rodent model of depression. This hypermethylated pattern was reversed to normal, as indicated by the control line, after chronic administration of escitalopram (a selective serotonin reuptake inhibitor; SSRI). The escitalopram-induced hypomethylation was associated with both an increase in P11 gene expression and a reduction in mRNA levels of two DNA methyltransferases that have been shown to maintain DNA methylation in adult forebrain neurons (Dnmt1 and Dnmt3a). In conclusion, our data further support a role for P11 in depression-like states and suggest that this gene is controlled by epigenetic mechanisms that can be affected by antidepressant treatment. PMID:21682946

Melas, Philippe A; Rogdaki, Maria; Lennartsson, Andreas; Björk, Karl; Qi, Hongshi; Witasp, Anna; Werme, Martin; Wegener, Gregers; Mathé, Aleksander A; Svenningsson, Per; Lavebratt, Catharina

2011-06-20

315

The Role of Genetic Sex in Affect Regulation and Expression of GABA-Related Genes Across Species.  

PubMed

Although circulating hormones and inhibitory gamma-aminobutyric acid (GABA)-related factors are known to affect mood, considerable knowledge gaps persist for biological mechanisms underlying the female bias in mood disorders. Here, we combine human and mouse studies to investigate sexual dimorphism in the GABA system in the context of major depressive disorder (MDD) and then use a genetic model to dissect the role of sex-related factors in GABA-related gene expression and anxiety-/depressive-like behaviors in mice. First, using meta-analysis of gene array data in human postmortem brain (N?=?51 MDD subjects, 50 controls), we show that the previously reported down-regulation in MDD of somatostatin (SST), a marker of a GABA neuron subtype, is significantly greater in women with MDD. Second, using gene co-expression network analysis in control human subjects (N?=?214; two frontal cortex regions) and expression quantitative trait loci mapping (N?=?170 subjects), we show that expression of SST and the GABA-synthesizing enzymes glutamate decarboxylase 67 (GAD67) and GAD65 are tightly co-regulated and influenced by X-chromosome genetic polymorphisms. Third, using a rodent genetic model [Four Core Genotypes (FCG) mice], in which genetic and gonadal sex are artificially dissociated (N???12/group), we show that genetic sex (i.e., X/Y-chromosome) influences both gene expression (lower Sst, Gad67, Gad65 in XY mice) and anxiety-like behaviors (higher in XY mice). This suggests that in an intact male animal, the observed behavior represents the outcomes of male genetic sex increasing and male-like testosterone decreasing anxiety-like behaviors. Gonadal sex was the only factor influencing depressive-like behavior (gonadal males?genetic sex) on GABA-related genes and anxiety-like behaviors. PMID:24062698

Seney, Marianne L; Chang, Lun-Ching; Oh, Hyunjung; Wang, Xingbin; Tseng, George C; Lewis, David A; Sibille, Etienne

2013-09-17

316

Genetic and Epigenetic Alteration among Three Homoeologous Genes of a Class E MADS Box Gene in Hexaploid Wheat[W][OA  

PubMed Central

Bread wheat (Triticum aestivum) is a hexaploid species with A, B, and D ancestral genomes. Most bread wheat genes are present in the genome as triplicated homoeologous genes (homoeologs) derived from the ancestral species. Here, we report that both genetic and epigenetic alterations have occurred in the homoeologs of a wheat class E MADS box gene. Two class E genes are identified in wheat, wheat SEPALLATA (WSEP) and wheat LEAFY HULL STERILE1 (WLHS1), which are homologs of Os MADS45 and Os MADS1 in rice (Oryza sativa), respectively. The three wheat homoeologs of WSEP showed similar genomic structures and expression profiles. By contrast, the three homoeologs of WLHS1 showed genetic and epigenetic alterations. The A genome WLHS1 homoeolog (WLHS1-A) had a structural alteration that contained a large novel sequence in place of the K domain sequence. A yeast two-hybrid analysis and a transgenic experiment indicated that the WLHS1-A protein had no apparent function. The B and D genome homoeologs, WLHS1-B and WLHS1-D, respectively, had an intact MADS box gene structure, but WLHS1-B was predominantly silenced by cytosine methylation. Consequently, of the three WLHS1 homoeologs, only WLHS1-D functions in hexaploid wheat. This is a situation where three homoeologs are differentially regulated by genetic and epigenetic mechanisms.

Shitsukawa, Naoki; Tahira, Chikako; Kassai, Ken-ichiro; Hirabayashi, Chizuru; Shimizu, Tomoaki; Takumi, Shigeo; Mochida, Keiichi; Kawaura, Kanako; Ogihara, Yasunari; Murai, Koji

2007-01-01

317

Genome-Wide Expression Patterns in Saccharomyces cerevisiae: Comparison of Drug Treatments and Genetic Alterations Affecting Biosynthesis of Ergosterol  

Microsoft Academic Search

Enzymes in the ergosterol-biosynthetic pathway are the targets of a number of antifungal agents including azoles, allylamines, and morpholines. In order to understand the response of Saccharomyces cerevisiae to perturbations in the ergosterol pathway, genome-wide transcript profiles following exposure to a number of antifungal agents targeting ergosterol biosynthesis (clotrimazole, fluconazole, itraconazole, ketoconazole, vori- conazole, terbinafine, and amorolfine) were obtained. These

GARY F. BAMMERT; JENNIFER M. FOSTEL

2000-01-01

318

The Genetics of Common Variation affecting Platelet Development, Function and Pharmaceutical Targeting  

PubMed Central

Summary Common variant effects on human platelet function and response to anti-platelet treatment have traditionally been studied using candidate gene approaches involving a limited number of variants and genes. These studies have often been undertaken in clinically defined cohorts. More recently, studies have applied genome-wide scans in larger population samples than prior candidate studies, in some cases scanning relatively healthy individuals. These studies demonstrate synergy with some prior candidate gene findings (e.g., GP6, ADRA2A) but also uncover novel loci involved in platelet function. Here, I summarise findings on common genetic variation influencing platelet development, function and therapeutics. Taken together, candidate gene and genome-wide studies begin to account for common variation in platelet function and provide information that may ultimately be useful in pharmacogenetic applications in the clinic. More than 50 loci have been identified with consistent associations with platelet phenotypes in ?2 populations. Several variants are under further study in clinical trials relating to anti-platelet therapies. In order to have useful clinical applications, variants must have large effects on a modifiable outcome. Regardless of clinical applications, studies of common genetic influences, even of small effect, offer additional insights into platelet biology including the importance of intracellular signalling and novel receptors. Understanding of common platelet-related genetics remains behind parallel fields (e.g., lipids, blood pressure) due to challenges in phenotype ascertainment. Further work is necessary to discover and characterise loci for platelet function, and to assess whether these loci contribute to disease aetiologies or response to therapeutics.

Johnson, Andrew D.

2011-01-01

319

?1-adrenoceptor genetic varians and ethnicity independently affect response to ?-blockade  

PubMed Central

Objectives Black subjects may be less responsive to ?-blockers than whites. Genetic variants in the ?1-adrenergic receptor (?1-AR) associated with lesser response to ?-blockers are more common in blacks than whites. The purpose of this study was to determine whether ethnic differences in response to ?-blockade can be explained by differing distributions of functional genetic variants in the ?1-AR. Methods We measured sensitivity to ?-blockade by the attenuation of exercise-induced tachycardia in 165 subjects (92 whites) who performed a graded bicycle exercise test before and 2.75 hours after oral atenolol (25 mg). We determined heart rate at rest and at 3 exercise levels from continuous ECG recordings and calculated the area-under-the-curve (AUC). We also measured plasma atenolol concentrations and determined genotypes for variants of the ?1-AR (Ser49Gly, Arg389Gly) and ?2C-AR (del322–325). The effects of ethnicity, genotype, and other covariates on the heart rate reduction after atenolol were estimated in multiple regression analyses. Results Atenolol resulted in a greater reduction in exercise heart rate in whites than blacks (P=0.006). ?1-AR Arg389 (P=0.003), but not the ?2C-AR 322–325 insertion allele (P=0.31), was independently associated with a greater reduction in heart rate AUC. Ethnic differences in sensitivity to atenolol remained significant (P=0.006) after adjustment for ?1-AR and ?2C-AR genotypes. Conclusions Ethnic differences in sensitivity to the ?1-blocker atenolol persist even after accounting for different distributions of functional genetic ?1-AR variants, suggesting that additional, as yet unidentified factors contribute to such ethnic differences.

Kurnik, Daniel; Li, Chun; Sofowora, Gbenga G.; Friedman, Eitan A.; Muszkat, Mordechai; Xie, Hong-Guang; Harris, Paul A.; Williams, Scott M.; Nair, Usha B.; Wood, Alastair J.J.; Stein, C. Michael

2009-01-01

320

Genetic investigations on 8 patients affected by ring 20 chromosome syndrome  

PubMed Central

Background Mosaic Chromosome 20 ring [r(20)] is a chromosomal disorder associated with a rare syndrome characterized by a typical seizure phenotype, a particular electroclinical pattern, cognitive impairment, behavioural problems and absence of a consistent pattern of dysmorphology. The pathogenic mechanism underlying seizures disorders in r(20) syndrome is still unknown. We performed a detailed clinical and genetic study on 8 patients with r(20) chromosome, aimed at detecting the genetic mechanism underlying r(20) syndrome. Methods We submitted 8 subjects with a previous diagnosis of ring 20 chromosome mosaicism to a clinical re-evaluation, followed by cytogenetic, FISH, array-CGH and molecular analyses. The genetic study was also extended to their available parents. Results FISH and array-CGH experiments indicate that cryptic deletions on chromosome 20 are not the cause of the r(20) chromosome associated disease. Moreover, no evidence of chromosome 20 uniparental disomy was found. Analysis of FISH signals given by variant in size alphoid tandem repeats probes on the normal chromosome 20 and the r(20) chromosome in the mosaic carriers suggests that the r(20) chromosome is the same chromosome not circularized in the "normal" cell line. Conclusions Higher percentages of r(20) chromosome cells were observed to be related with precocious age at seizure onset and with resistance to antiepileptic drug treatment. Behavioural problems also seem to be associated with higher percentages of r(20) chromosome cells. Our results suggest that an epigenetic mechanism perturbing the expression of genes close to the telomeric regions, rather than deletion of genes located at the distal 20p and/or 20q regions, may underlie the manifestation of r(20) syndrome.

2010-01-01

321

Genetic clonality of Plasmodium falciparum affects the outcome of infection in Anopheles gambiae.  

PubMed

Mosquito infections with natural isolates of Plasmodium falciparum are notoriously variable and pose a problem for reliable evaluation of efficiency of transmission-blocking agents for malaria control interventions. Here, we show that monoclonal P. falciparum isolates produce higher parasite loads than mixed ones. Induction of the mosquito immune responses by wounding efficiently decreases Plasmodium numbers in monoclonal infections but fails to do so in infections with two or more parasite genotypes. Our results point to the parasites genetic complexity as a potentially crucial component of mosquito-parasite interactions. PMID:22554991

Nsango, Sandrine E; Abate, Luc; Thoma, Martine; Pompon, Julien; Fraiture, Malou; Rademacher, Annika; Berry, Antoine; Awono-Ambene, Parfait H; Levashina, Elena A; Morlais, Isabelle

2012-04-24

322

Genetic manipulation of polyphosphate metabolism affects cadmium tolerance in Escherichia coli.  

PubMed Central

The polyphosphate metabolic pathways in Escherichia coli were genetically manipulated to test the effect of polyphosphate on tolerance to cadmium. A polyphosphate kinase (ppk) and polyphosphatase (ppx) mutant strain produced no polyphosphate, whereas the same strain carrying multiple copies of ppk on a high-copy plasmid produced significant quantities. The doubling times of both strains increased with increasing cadmium concentrations. In contrast, the mutant strain carrying multiple copies of ppk and ppx produced 1/20 of the polyphosphate found in the strain carrying multiple copies of ppk only and showed no significant increase in doubling time over the same cadmium concentration range.

Keasling, J D; Hupf, G A

1996-01-01

323

Drug-Induced Decrease of Protein Kinase A Activity Reveals Alteration in BDNF Expression of Bipolar Affective Disorder  

Microsoft Academic Search

Bipolar affective disorder (BAD) is a severe disease whose molecular and cellular bases are not well known. The aim of the present study was to probe the cAMP signaling downstream targets by pharmacologically manipulating the protein kinase A (PKA) enzyme, along with the assessment of brain-derived neurotrophic factor (BDNF) expression in lymphoblasts. The time course of lymphoblast PKA activity (up

Félicien Karege; Michèle Schwald; Rachid El Kouaissi

2004-01-01

324

Water deficit alters differentially metabolic pathways affecting important flavor and quality traits in grape berries of Cabernet Sauvignon and Chardonnay  

Microsoft Academic Search

BACKGROUND: Water deficit has significant effects on grape berry composition resulting in improved wine quality by the enhancement of color, flavors, or aromas. While some pathways or enzymes affected by water deficit have been identified, little is known about the global effects of water deficit on grape berry metabolism. RESULTS: The effects of long-term, seasonal water deficit on berries of

Laurent G Deluc; David R Quilici; Alain Decendit; Jérôme Grimplet; Matthew D Wheatley; Karen A Schlauch; Jean-Michel Mérillon; John C Cushman; Grant R Cramer

2009-01-01

325

Roosters affected by epididymal lithiasis present local alteration in vitamin D3, testosterone and estradiol levels as well as estrogen receptor 2 (beta) expression.  

PubMed

Epididymal lithiasis is a reproductive dysfunction of roosters that is associated with loss of fertility and is characterized by the formation of calcium stones in the lumen of the efferent ductules of the epididymal region. The efferent ductules of birds are responsible for the reabsorption of the fluid coming from the testis as well as luminal calcium. It has been hypothesized that the epididymal stone formation may be related to the impairment of local fluid or calcium homeostasis, which depends on hormones such as estradiol (E(2)). Therefore, this study aimed to investigate possible alterations in the expression of ER? (ESR1) and ER? (ESR2) in the epididymal region of roosters affected by epididymal lithiasis. The study was performed by immunohistochemistry and western blotting assays. In addition, the concentrations of E(2), vitamin D3, and testosterone, which are also key hormones in maintenance of calcium homeostasis, were determined in the plasma and epididymal region, by ELISA. It was observed that ESR2 expression is increased in all segments of the epididymal region of affected roosters, whereas ESR1 levels are not altered. Moreover, the hormone concentration profiles were changed, as in the epididymal region of roosters with lithiasis the E(2) levels were increased and vitamin D3 as well as testosterone concentrations were significantly decreased. These results suggest that a hormonal imbalance may be involved with the origin and progression of the epididymal lithiasis, possibly by affecting the local fluid or calcium homeostasis. PMID:21670126

Oliveira, André G; Dornas, Rubem A P; Praes, Lílian C; Hess, Rex A; Mahecha, Germán A B; Oliveira, Cleida A

2011-06-13

326

Specific Alterations in Complement Protein Activity of Little Brown Myotis (Myotis lucifugus) Hibernating in White-Nose Syndrome Affected Sites  

PubMed Central

White-nose syndrome (WNS) is the most devastating condition ever reported for hibernating bats, causing widespread mortality in the northeastern United States. The syndrome is characterized by cutaneous lesions caused by a recently identified psychrophilic and keratinophylic fungus (Geomyces destructans), depleted fat reserves, atypical behavior, and damage to wings; however, the proximate cause of mortality is still uncertain. To assess relative levels of immunocompetence in bats hibernating in WNS-affected sites compared with levels in unaffected bats, we describe blood plasma complement protein activity in hibernating little brown myotis (Myotis lucifugus) based on microbicidal competence assays using Escherichia coli, Staphylococcus aureus and Candida albicans. Blood plasma from bats collected during mid-hibernation at WNS-affected sites had higher bactericidal ability against E. coli and S. aureus, but lower fungicidal ability against C. albicans when compared with blood plasma from bats collected at unaffected sites. Within affected sites during mid-hibernation, we observed no difference in microbicidal ability between bats displaying obvious fungal infections compared to those without. Bactericidal ability against E. coli decreased significantly as hibernation progressed in bats collected from an affected site. Bactericidal ability against E. coli and fungicidal ability against C. albicans were positively correlated with body mass index (BMI) during late hibernation. We also compared complement activity against the three microbes within individuals and found that the ability of blood plasma from hibernating M. lucifugus to lyse microbial cells differed as follows: E. coli>S. aureus>C. albicans. Overall, bats affected by WNS experience both relatively elevated and reduced innate immune responses depending on the microbe tested, although the cause of observed immunological changes remains unknown. Additionally, considerable trade-offs may exist between energy conservation and immunological responses. Relationships between immune activity and torpor, including associated energy expenditure, are likely critical components in the development of WNS.

Moore, Marianne S.; Reichard, Jonathan D.; Murtha, Timothy D.; Zahedi, Bita; Fallier, Renee M.; Kunz, Thomas H.

2011-01-01

327

Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral  

PubMed Central

In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone. Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47 day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a semi-synthetic diet containing 0.6% calcium and 0.6% phosphorus for 2 or 4 weeks and ?-APN treated animals were fed additionally with ?-aminopropionitrile (0.1% dry weight). At the end of this period the rats in the four groups were sacrificed, and L2–L6 vertebra were collected. Collagen cross-links were determined by both biochemical and spectroscopic (Fourier transform infrared imaging (FTIRI)) analyses. Mineral content and distribution (BMDD) were determined by quantitative backscattered electron imaging (qBEI), and mineral maturity/crystallinity by FTIRI techniques. Micro-CT was used to describe the architectural properties. Mechanical performance of whole bone as well as of bone matrix material was tested by vertebral compression tests and by nano-indentation, respectively. The data of the present study indicate that ?-APN treatment changed whole vertebra properties compared to non-treated rats, including collagen cross-links pattern, trabecular bone volume to tissue ratio and trabecular thickness, which were all decreased (p < 0.05). Further, compression tests revealed a significant negative impact of ?-APN treatment on maximal force to failure and energy to failure, while stiffness was not influenced. Bone mineral density distribution (BMDD) was not altered either. At the material level, ?-APN treated rats exhibited increased Pyd/Divalent cross-link ratios in areas confined to a newly formed bone. Moreover, nano-indentation experiments showed that the E-modulus and hardness were reduced only in newly formed bone areas under the influence of ?-APN, despite a similar mineral content. In conclusion the results emphasize the pivotal role of collagen cross-links in the determination of bone quality and mechanical integrity. However, in this rat animal model of lathyrism, the coupled alterations of tissue structural properties make it difficult to weigh the contribution of the anatomically confined material changes to the overall mechanical performance of whole bone. Interestingly, the collagen cross-link ratio in bone forming areas had the same profile as seen in actively bone forming trabecular surfaces in human iliac crest biopsies of osteoporotic patients.

Paschalis, E.P.; Tatakis, D.N.; Robins, S.; Fratzl, P.; Manjubala, I.; Zoehrer, R.; Gamsjaeger, S.; Buchinger, B.; Roschger, A.; Phipps, R.; Boskey, A.L.; Dall'Ara, E.; Varga, P.; Zysset, P.; Klaushofer, K.; Roschger, P.

2011-01-01

328

Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral.  

PubMed

In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone. Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47 day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a semi-synthetic diet containing 0.6% calcium and 0.6% phosphorus for 2 or 4 weeks and ?-APN treated animals were fed additionally with ?-aminopropionitrile (0.1% dry weight). At the end of this period the rats in the four groups were sacrificed, and L2-L6 vertebra were collected. Collagen cross-links were determined by both biochemical and spectroscopic (Fourier transform infrared imaging (FTIRI)) analyses. Mineral content and distribution (BMDD) were determined by quantitative backscattered electron imaging (qBEI), and mineral maturity/crystallinity by FTIRI techniques. Micro-CT was used to describe the architectural properties. Mechanical performance of whole bone as well as of bone matrix material was tested by vertebral compression tests and by nano-indentation, respectively. The data of the present study indicate that ?-APN treatment changed whole vertebra properties compared to non-treated rats, including collagen cross-links pattern, trabecular bone volume to tissue ratio and trabecular thickness, which were all decreased (p<0.05). Further, compression tests revealed a significant negative impact of ?-APN treatment on maximal force to failure and energy to failure, while stiffness was not influenced. Bone mineral density distribution (BMDD) was not altered either. At the material level, ?-APN treated rats exhibited increased Pyd/Divalent cross-link ratios in areas confined to a newly formed bone. Moreover, nano-indentation experiments showed that the E-modulus and hardness were reduced only in newly formed bone areas under the influence of ?-APN, despite a similar mineral content. In conclusion the results emphasize the pivotal role of collagen cross-links in the determination of bone quality and mechanical integrity. However, in this rat animal model of lathyrism, the coupled alterations of tissue structural properties make it difficult to weigh the contribution of the anatomically confined material changes to the overall mechanical performance of whole bone. Interestingly, the collagen cross-link ratio in bone forming areas had the same profile as seen in actively bone forming trabecular surfaces in human iliac crest biopsies of osteoporotic patients. PMID:21920485

Paschalis, E P; Tatakis, D N; Robins, S; Fratzl, P; Manjubala, I; Zoehrer, R; Gamsjaeger, S; Buchinger, B; Roschger, A; Phipps, R; Boskey, A L; Dall'Ara, E; Varga, P; Zysset, P; Klaushofer, K; Roschger, P

2011-09-02

329

How Malaria Has Affected the Human Genome and What Human Genetics Can Teach Us about Malaria  

PubMed Central

Malaria is a major killer of children worldwide and the strongest known force for evolutionary selection in the recent history of the human genome. The past decade has seen growing evidence of ethnic differences in susceptibility to malaria and of the diverse genetic adaptations to malaria that have arisen in different populations: epidemiological confirmation of the hypotheses that G6PD deficiency, ?+ thalassemia, and hemoglobin C protect against malaria mortality; the application of novel haplotype-based techniques demonstrating that malaria-protective genes have been subject to recent positive selection; the first genetic linkage maps of resistance to malaria in experimental murine models; and a growing number of reported associations with resistance and susceptibility to human malaria, particularly in genes involved in immunity, inflammation, and cell adhesion. The challenge for the next decade is to build the global epidemiological infrastructure required for statistically robust genomewide association analysis, as a way of discovering novel mechanisms of protective immunity that can be used in the development of an effective malaria vaccine.

Kwiatkowski, Dominic P.

2005-01-01

330

COMT genetic variation confers risk for psychotic and affective disorders: a case control study  

Microsoft Academic Search

BACKGROUND: Variation in the COMT gene has been implicated in a number of psychiatric disorders, including psychotic, affective and anxiety disorders. The majority of these studies have focused on the functional Val108\\/158Met polymorphism and yielded conflicting results, with limited studies examining the relationship between other polymorphisms, or haplotypes, and psychiatric illness. We hypothesized that COMT variation may confer a general

Birgit Funke; Anil K Malhotra; Christine T Finn; Alex M Plocik; Stephen L Lake; Todd Lencz; Pamela DeRosse; John M Kane; Raju Kucherlapati

2005-01-01

331

The Heritability of Bipolar Affective Disorder and the Genetic Relationship to Unipolar Depression  

Microsoft Academic Search

Background: Twin studies of bipolar affective disor- der (BPD) have either been small or have not used ex- plicit diagnostic criteria. There has been little use of ge- netic model fitting and no analyses to explore the etiological overlap with unipolar depression (UPD). Methods: Sixty-seven twin pairs, 30 monozygotic and 37 dizygotic, in which the proband had BPD were ascer-

Peter McGuffin; Fruhling Rijsdijk; Martin Andrew; Pak Sham; Randy Katz; Alastair Cardno

2003-01-01

332

Endocannabinoid Receptor Deficiency Affects Maternal Care and Alters the Dam's Hippocampal Oxytocin Receptor and Brain-Derived Neurotrophic Factor Expression.  

PubMed

Maternal care is the newborn's first experience of social interaction, and this influences infant survival, development and social competences throughout life. We recently found that postpartum blocking of the endocannabinoid receptor-1 (CB1R) altered maternal behaviour. In the present study, maternal care was assessed by the time taken to retrieve pups, pups' ultrasonic vocalisations (USVs) and pup body weight, comparing CB1R deleted (CB1R KO) versus wild-type (WT) mice. After culling on postpartum day 8, hippocampal expression of oxytocin receptor (OXTR), brain-derived neurotrophic factor (BDNF) and stress-mediating factors were evaluated in CB1R KO and WT dams. Comparisons were also performed with nulliparous (NP) CB1R KO and WT mice. Compared to WT, CB1R KO dams were slower to retrieve their pups. Although the body weight of the KO pups did not differ from the weight of WT pups, they emitted fewer USVs. This impairment of the dam-pup relationship correlated with a significant reduction of OXTR mRNA and protein levels among CB1R KO dams compared to WT dams. Furthermore, WT dams exhibited elevated OXTR mRNA expression, as well as increased levels of mineralocorticoid and glucocorticoid receptors, compared to WT NP mice. By contrast, CB1R KO dams showed no such elevation of OXTR expression, alongside lower BDNF and mineralocorticoid receptors, as well as elevated corticotrophin-releasing hormone mRNA levels, when compared to CB1R KO NP. Thus, it appears that the disruption of endocannabinoid signalling by CB1R deletion alters expression of the OXTR, apparently leading to deleterious effects upon maternal behaviour. PMID:23895426

Schechter, M; Weller, A; Pittel, Z; Gross, M; Zimmer, A; Pinhasov, A

2013-10-01

333

A genetic polymorphism affecting reliance on personal versus public information in a spatial learning task in Drosophila melanogaster.  

PubMed

Organisms that face behavioural challenges can use different types of information to guide their decisions. First, they can use the personal information they sample in their environment. Second, they can use the inadvertent social information provided by the behaviour of conspecifics or heterospecifics (i.e. public information). Currently, little is known about the interaction between genetic variation and the use of personal versus public information in natural populations. Here, we investigated whether a natural genetic polymorphism affects the use of personal versus public information in a spatial learning task in Drosophila melanogaster. We found that genetic variation at the foraging locus interacts with social context during spatial learning. While both allelic variants are able to use personal and public information to improve their navigation during 10 training trials, a probe trial revealed that individuals carrying the for(R) (rover) allele rely mainly on personal information, whereas individuals carrying the for(s) (sitter) allele either use or display more public information than rovers. Accordingly, transfer of social information is more important in groups of sitters than in groups of rovers. These results suggest that a positive feedback loop can occur between alleles promoting group living, such as for(s), and the use and/or display of public information, ultimately providing the opportunity for the joint evolution of sociality and cultural traits. PMID:23576793

Foucaud, Julien; Philippe, Anne-Sophie; Moreno, Celine; Mery, Frederic

2013-04-10

334

Genetic variants affecting the neural processing of human facial expressions: evidence using a genome-wide functional imaging approach  

PubMed Central

Human faces present crucial visual information for social interaction. Specialized brain regions are involved in the perception of faces, with the fusiform face area (FFA) a key neuronal substrate. Face processing is genetically controlled, but by which specific genes is unknown. A genome-wide approach identified common single nucleotide polymorphisms (SNPs) associated with areas of increased brain activity in response to affective facial expressions, measured with functional magnetic resonance imaging. SNPs in 20 genetic regions were linked with neural responses to negative facial expressions in a Norwegian sample (n=246), which included patients with mental illness. Three genetic regions were linked with FFA activation in a further discovery experiment using positive facial expressions and involving many of the same individuals (n=284). Two of these three regions showed significant association with right FFA activation to negative facial expressions in an independent North American replication sample of healthy Caucasians (n=85, 3q26.31, P=0.004; 20p12.3, P=0.045). The activation patterns were particularly striking for the SNP in 3q26.31, which lies in a gene TMEM212; only the FFA was activated. The specialized function of this brain region suggests that TMEM212 could contribute to the innate architecture of face processing.

Brown, A A; Jensen, J; Nikolova, Y S; Djurovic, S; Agartz, I; Server, A; Ferrell, R E; Manuck, S B; Mattingsdal, M; Melle, I; Hariri, A R; Frigessi, A; Andreassen, O A

2012-01-01

335

Genetic mapping of quantitative trait loci affecting susceptibility to Marek's disease virus induced tumors in F2 intercross chickens.  

PubMed Central

Marek's disease (MD) is a lymphoproliferative disease caused by the MD virus (MDV), which costs the poultry industry nearly $1 billion annually. To identify quantitative trait loci (QTL) affecting MD susceptibility, the inbred lines 6(3) (MD resistant) and 7(2) (MD susceptible) were mated to create more than 300 F2 chickens. The F2 chickens were challenged with MDV JM strain, moderately virulent) at 1 wk of age and assessed for MD susceptibility. The QTL analysis was divided into three stages. In stage 1, 65 DNA markers selected from the chicken genetic maps were typed on the 40 most MD-susceptible and the 40 most MD-resistant F2 chickens, and 21 markers residing near suggestive QTL were revealed by analysis of variance (ANOVA). In stage 2, the suggestive markers plus available flanking markers were typed on 272 F2 chickens, and three suggestive QTL were identified by ANOVA. In stage 3, using the interval mapping program Map Manager and permutation tests, two significant and two suggestive MD QTL were identified on four chromosomal subregions. Three to five loci collected explained between 11 and 23% of the phenotypic MD variation, or 32-68% of the genetic variance. This study constitutes the first report in the domestic chicken on the mapping of non-major histocompatibility complex QTL affecting MD susceptibility.

Vallejo, R L; Bacon, L D; Liu, H C; Witter, R L; Groenen, M A; Hillel, J; Cheng, H H

1998-01-01

336

Host Genetic Variation Affects Resistance to Infection with a Highly Pathogenic H5N1 Influenza A Virus in Mice ? †  

PubMed Central

Despite the prevalence of H5N1 influenza viruses in global avian populations, comparatively few cases have been diagnosed in humans. Although viral factors almost certainly play a role in limiting human infection and disease, host genetics most likely contribute substantially. To model host factors in the context of influenza virus infection, we determined the lethal dose of a highly pathogenic H5N1 virus (A/Hong Kong/213/03) in C57BL/6J and DBA/2J mice and identified genetic elements associated with survival after infection. The lethal dose in these hosts varied by 4 logs and was associated with differences in replication kinetics and increased production of proinflammatory cytokines CCL2 and tumor necrosis factor alpha in susceptible DBA/2J mice. Gene mapping with recombinant inbred BXD strains revealed five loci or Qivr (quantitative trait loci for influenza virus resistance) located on chromosomes 2, 7, 11, 15, and 17 associated with resistance to H5N1 virus. In conjunction with gene expression profiling, we identified a number of candidate susceptibility genes. One of the validated genes, the hemolytic complement gene, affected virus titer 7 days after infection. We conclude that H5N1 influenza virus-induced pathology is affected by a complex and multigenic host component.

Boon, Adrianus C. M.; deBeauchamp, Jennifer; Hollmann, Anna; Luke, Jennifer; Kotb, Malak; Rowe, Sarah; Finkelstein, David; Neale, Geoffrey; Lu, Lu; Williams, Robert W.; Webby, Richard J.

2009-01-01

337

Alterations in Cytosolic Glucose-Phosphate Metabolism Affect Structural Features and Biochemical Properties of Starch-Related Heteroglycans  

Microsoft Academic Search

The cytosolic pools of glucose-1-phosphate (Glc-1-P) and glucose-6-phosphate areessential intermediates in several biosynthetic paths, including the formation of sucrose and cell wall constituents, and they are also linked to the cytosolic starch-related heteroglycans. In this work, structural features and biochemical properties of starch-related heteroglycans were analyzed as affected by the cytosolic glucose monophosphate metabolism using both source and sink organs

Joerg Fettke; Adriano Nunes-Nesi; Jessica Alpers; Michal Szkop; Alisdair R. Fernie; Martin Steup

2008-01-01

338

Evidence for a genetic association between alleles of monoamine oxidase A gene and bipolar affective disorder  

SciTech Connect

We present evidence of a genetic association between bipolar disorder and alleles at 3 monoamine oxidase A (MAOA) markers, but not with alleles of a monoamine oxidase B (MAOB) polymorphism. The 3 MAOA markers, including one associated with low MAOA activity, show strong allelic association with each other but surprisingly not with MAOB. Our results are significantly only for females, though the number of males in our sample is too small to draw any definite conclusions. Our data is consistent with recent reports of reduced MAOA activity in patients with abnormal behavioral phenotypes. The strength of the association is weak, but significant, which suggests that alleles at the MAOA locus contribute to susceptibility to bipolar disorder rather than being a major determinant. 58 refs., 1 fig., 3 tabs.

Lim, L.C.C.; Sham, P.; Castle, D. [Institute of Psychiatry, London (United Kingdom)] [and others

1995-08-14

339

Oxytocin and vasopressin are dysregulated in Williams Syndrome, a genetic disorder affecting social behavior.  

PubMed

The molecular and neural mechanisms regulating human social-emotional behaviors are fundamentally important but largely unknown; unraveling these requires a genetic systems neuroscience analysis of human models. Williams Syndrome (WS), a condition caused by deletion of ~28 genes, is associated with a gregarious personality, strong drive to approach strangers, difficult peer interactions, and attraction to music. WS provides a unique opportunity to identify endogenous human gene-behavior mechanisms. Social neuropeptides including oxytocin (OT) and arginine vasopressin (AVP) regulate reproductive and social behaviors in mammals, and we reasoned that these might mediate the features of WS. Here we established blood levels of OT and AVP in WS and controls at baseline, and at multiple timepoints following a positive emotional intervention (music), and a negative physical stressor (cold). We also related these levels to standardized indices of social behavior. Results revealed significantly higher median levels of OT in WS versus controls at baseline, with a less marked increase in AVP. Further, in WS, OT and AVP increased in response to music and to cold, with greater variability and an amplified peak release compared to controls. In WS, baseline OT but not AVP, was correlated positively with approach, but negatively with adaptive social behaviors. These results indicate that WS deleted genes perturb hypothalamic-pituitary release not only of OT but also of AVP, implicating more complex neuropeptide circuitry for WS features and providing evidence for their roles in endogenous regulation of human social behavior. The data suggest a possible biological basis for amygdalar involvement, for increased anxiety, and for the paradox of increased approach but poor social relationships in WS. They also offer insight for translating genetic and neuroendocrine knowledge into treatments for disorders of social behavior. PMID:22719898

Dai, Li; Carter, C Sue; Ying, Jian; Bellugi, Ursula; Pournajafi-Nazarloo, Hossein; Korenberg, Julie R

2012-06-12

340

Ethnicity and race and systemic sclerosis: How it affects susceptibility, severity, antibody genetics, and clinical manifestations  

Microsoft Academic Search

Most studies have suggested that ethnic factors impact significantly on systemic sclerosis. Extensive epidemiologic studies\\u000a have been carried out in white individuals, and limited data suggest that blacks are affected twice as frequently; Japanese\\u000a patients have a lower prevalence than whites. This highest rate that has been described has been in Choctaw Native Americans.\\u000a Blacks have a lower age at

John D. Reveille

2003-01-01

341

Genetic linkage between X-chromosome markers and bipolar affective illness  

Microsoft Academic Search

A pedigree study shows close linkage of bipolar affective illness (manic depression) to the X-chromosome markers colour blindness and glucose-6-phosphate dehydrogenase deficiency. The maximum lod score ranges from 7.52 (assuming homogeneity) to 9.17 (assuming heterogeneity); that is, the odds in favour of linkage range between 3×107 to 1 and 109 to 1. These results provide confirmation that a major psychiatric

Miron Baron; Neil Risch; Rahel Hamburger; Batsheva Mandel; Stuart Kushner; Michael Newman; Dov Drumer; Robert H. Belmaker

1987-01-01

342

Water deficit alters differentially metabolic pathways affecting important flavor and quality traits in grape berries of Cabernet Sauvignon and Chardonnay  

PubMed Central

Background Water deficit has significant effects on grape berry composition resulting in improved wine quality by the enhancement of color, flavors, or aromas. While some pathways or enzymes affected by water deficit have been identified, little is known about the global effects of water deficit on grape berry metabolism. Results The effects of long-term, seasonal water deficit on berries of Cabernet Sauvignon, a red-wine grape, and Chardonnay, a white-wine grape were analyzed by integrated transcript and metabolite profiling. Over the course of berry development, the steady-state transcript abundance of approximately 6,000 Unigenes differed significantly between the cultivars and the irrigation treatments. Water deficit most affected the phenylpropanoid, ABA, isoprenoid, carotenoid, amino acid and fatty acid metabolic pathways. Targeted metabolites were profiled to confirm putative changes in specific metabolic pathways. Water deficit activated the expression of numerous transcripts associated with glutamate and proline biosynthesis and some committed steps of the phenylpropanoid pathway that increased anthocyanin concentrations in Cabernet Sauvignon. In Chardonnay, water deficit activated parts of the phenylpropanoid, energy, carotenoid and isoprenoid metabolic pathways that contribute to increased concentrations of antheraxanthin, flavonols and aroma volatiles. Water deficit affected the ABA metabolic pathway in both cultivars. Berry ABA concentrations were highly correlated with 9-cis-epoxycarotenoid dioxygenase (NCED1) transcript abundance, whereas the mRNA expression of other NCED genes and ABA catabolic and glycosylation processes were largely unaffected. Water deficit nearly doubled ABA concentrations within berries of Cabernet Sauvignon, whereas it decreased ABA in Chardonnay at véraison and shortly thereafter. Conclusion The metabolic responses of grapes to water deficit varied with the cultivar and fruit pigmentation. Chardonnay berries, which lack any significant anthocyanin content, exhibited increased photoprotection mechanisms under water deficit conditions. Water deficit increased ABA, proline, sugar and anthocyanin concentrations in Cabernet Sauvignon, but not Chardonnay berries, consistent with the hypothesis that ABA enhanced accumulation of these compounds. Water deficit increased the transcript abundance of lipoxygenase and hydroperoxide lyase in fatty metabolism, a pathway known to affect berry and wine aromas. These changes in metabolism have important impacts on berry flavor and quality characteristics. Several of these metabolites are known to contribute to increased human-health benefits.

Deluc, Laurent G; Quilici, David R; Decendit, Alain; Grimplet, Jerome; Wheatley, Matthew D; Schlauch, Karen A; Merillon, Jean-Michel; Cushman, John C; Cramer, Grant R

2009-01-01

343

Cellular Mg++ accumulation is altered by extracellular Na+ and directly affects agonist-induced mobilization of Ca++ in vascular smooth muscle.  

PubMed

Effects of altered Na+, Ca++ and Mg++ concentrations on 45Ca and 28Mg distribution and binding as well as of changes in cellular Mg++ on mobilization of Ca++ by added norepinephrine (NE) were examined in the rabbit aortic media-intimal layer. Uptake of 45Ca at cellular high affinity sites was decreased by Mg++ much more than 28Mg uptake was altered by Ca++. Substitution of Na+ affects 45Ca uptake primarily at extracellular (La( )-accessible) binding sites. Muscles were pre-loaded with Mg++ by incubation in a low-Na+ solution (75% Na+ replaced isosmotically with sucrose) for 30 min followed by a 90 min exposure to a similar solution also containing 15 mM MgCl2. These tissues, upon examination in normal (154 mM) Na(+)-containing solution, indicated decreased retention of that cellular, high-affinity Ca++ fraction important for NE-induced contractile response. Accordingly, release of 45Ca from this site and associated tension responses to added NE were attenuated in these muscles. These results suggest that variations in extracellular Na+ concentration modulate binding and subsequent mobilization of activator Ca++ by agonists through alterations in cellular Mg++ content in vascular smooth muscle. PMID:1529761

Shetty, S S; Zawadzki, J V; Weiss, G B

1992-01-01

344

MYC protein expression and genetic alterations have prognostic impact in patients with diffuse large B-cell lymphoma treated with immunochemotherapy  

PubMed Central

MYC alterations influence the survival of patients with diffuse large B-cell lymphoma. Most studies have focused on MYC translocations but there is little information regarding the impact of numerical alterations and protein expression. We analyzed the genetic alterations and protein expression of MYC, BCL2, BCL6, and MALT1 in 219 cases of diffuse large B-cell lymphoma. MYC rearrangement occurred as the sole abnormality (MYC single-hit) in 3% of cases, MYC and concurrent BCL2 and/or BCL6 rearrangements (MYC double/triple-hit) in 4%, MYC amplifications in 2% and MYC gains in 19%. MYC single-hit, MYC double/triple-hit and MYC amplifications, but not MYC gains or other gene rearrangements, were associated with unfavorable progression-free survival and overall survival. MYC protein expression, evaluated using computerized image analysis, captured the unfavorable prognosis of MYC translocations/amplifications and identified an additional subset of patients without gene alterations but with similar poor prognosis. Patients with tumors expressing both MYC/BCL2 had the worst prognosis, whereas those with double-negative tumors had the best outcome. High MYC expression was associated with shorter overall survival irrespectively of the International Prognostic Index and BCL2 expression. In conclusion, MYC protein expression identifies a subset of diffuse large B-cell lymphoma with very poor prognosis independently of gene alterations and other prognostic parameters.

Valera, Alexandra; Lopez-Guillermo, Armando; Cardesa-Salzmann, Teresa; Climent, Fina; Gonzalez-Barca, Eva; Mercadal, Santiago; Espinosa, Inigo; Novelli, Silvana; Briones, Javier; Mate, Jose L.; Salamero, Olga; Sancho, Juan M.; Arenillas, Leonor; Serrano, Sergi; Erill, Nadina; Martinez, Daniel; Castillo, Paola; Rovira, Jordina; Martinez, Antonio; Campo, Elias; Colomo, Luis

2013-01-01

345

Alterations of social interaction through genetic and environmental manipulation of the 22q11.2 gene Sept5 in the mouse brain.  

PubMed

Social behavior dysfunction is a symptomatic element of schizophrenia and autism spectrum disorder (ASD). Although altered activities in numerous brain regions are associated with defective social cognition and perception, the causative relationship between these altered activities and social cognition and perception-and their genetic underpinnings-are not known in humans. To address these issues, we took advantage of the link between hemizygous deletion of human chromosome 22q11.2 and high rates of social behavior dysfunction, schizophrenia and ASD. We genetically manipulated Sept5, a 22q11.2 gene, and evaluated its role in social interaction in mice. Sept5 deficiency, against a high degree of homogeneity in a congenic genetic background, selectively impaired active affiliative social interaction in mice. Conversely, virally guided overexpression of Sept5 in the hippocampus or, to a lesser extent, the amygdala elevated levels of active affiliative social interaction in C57BL/6J mice. Congenic knockout mice and mice overexpressing Sept5 in the hippocampus or amygdala were indistinguishable from control mice in novelty and olfactory responses, anxiety or motor activity. Moreover, post-weaning individual housing, an environmental condition designed to reduce stress in male mice, selectively raised levels of Sept5 protein in the amygdala and increased active affiliative social interaction in C57BL/6J mice. These findings identify this 22q11.2 gene in the hippocampus and amygdala as a determinant of social interaction and suggest that defective social interaction seen in 22q11.2-associated schizophrenia and ASD can be genetically and environmentally modified by altering this 22q11.2 gene. PMID:22589251

Harper, Kathryn M; Hiramoto, Takeshi; Tanigaki, Kenji; Kang, Gina; Suzuki, Go; Trimble, William; Hiroi, Noboru

2012-05-15

346

Alteration of seed fatty acid composition by an ethyl methanesulfonate-induced mutation in Arabidopsis thaliana affecting diacylglycerol acyltransferase activity.  

PubMed Central

In characterizing the enzymes involved in the formation of very long-chain fatty acids (VLCFAs) in the Brassicaceae, we have generated a series of mutants of Arabidopsis thaliana that have reduced VLCFA content. Here we report the characterization of a seed lipid mutant, AS11, which, in comparison to wild type (WT), has reduced levels of 20:1 and 18:1 and accumulates 18:3 as the major fatty acid in triacylglycerols. Proportions of 18:2 remain similar to WT. Genetic analyses indicate that the fatty acid phenotype is caused by a semidominant mutation in a single nuclear gene, designated TAG1, located on chromosome 2. Biochemical analyses have shown that the AS11 phenotype is not due to a deficiency in the capacity to elongate 18:1 or to an increase in the relative delta 15 or delta 12 desaturase activities. Indeed, the ratio of desaturase/elongase activities measured in vitro is virtually identical in developing WT and AS11 seed homogenates. Rather, the fatty acid phenotype of AS11 is the result of reduced diacylglycerol acyltransferase activity throughout development, such that triacylglycerol biosynthesis is reduced. This leads to a reduction in 20:1 biosynthesis during seed development, leaving more 18:1 available for desaturation. Thus, we have demonstrated that changes to triacylglycerol biosynthesis can result in dramatic changes in fatty acid composition and, in particular, in the accumulation of VLCFAs in seed storage lipids.

Katavic, V; Reed, D W; Taylor, D C; Giblin, E M; Barton, D L; Zou, J; Mackenzie, S L; Covello, P S; Kunst, L

1995-01-01

347

Diet-induced alterations of host cholesterol metabolism are likely to affect the gut microbiota composition in hamsters.  

PubMed

The gastrointestinal microbiota affects the metabolism of the mammalian host and has consequences for health. However, the complexity of gut microbial communities and host metabolic pathways make functional connections difficult to unravel, especially in terms of causation. In this study, we have characterized the fecal microbiota of hamsters whose cholesterol metabolism was extensively modulated by the dietary addition of plant sterol esters (PSE). PSE intake induced dramatic shifts in the fecal microbiota, reducing several bacterial taxa within the families Coriobacteriaceae and Erysipelotrichaceae. The abundance of these taxa displayed remarkably high correlations with host cholesterol metabolites. Most importantly, the associations between several bacterial taxa with fecal and biliary cholesterol excretion showed an almost perfect fit to a sigmoidal nonlinear model of bacterial inhibition, suggesting that host cholesterol excretion can shape microbiota structure through the antibacterial action of cholesterol. In vitro experiments suggested a modest antibacterial effect of cholesterol, and especially of cholesteryl-linoleate, but not plant sterols when included in model bile micelles. The findings obtained in this study are relevant to our understanding of gut microbiota-host lipid metabolism interactions, as they provide the first evidence for a role of cholesterol excreted with the bile as a relevant host factor that modulates the gut microbiota. The findings further suggest that the connections between Coriobacteriaceae and Erysipelotrichaceae and host lipid metabolism, which have been observed in several studies, could be caused by a metabolic phenotype of the host (cholesterol excretion) affecting the gut microbiota. PMID:23124234

Martínez, Inés; Perdicaro, Diahann J; Brown, Andrew W; Hammons, Susan; Carden, Trevor J; Carr, Timothy P; Eskridge, Kent M; Walter, Jens

2012-11-02

348

Genetic Analysis of Mutations Affecting Growth of SACCHAROMYCES CEREVISIAE at Low Temperature  

PubMed Central

A large number of genes control growth of the yeast Saccharomyces cerevisiae at low temperatures (< 10°). Approximately 47 percent of the mutants selected for inability to grow at 4–5°C show increased sensitivity to cycloheximide. In 3 of 4 cases tested, supersensitivity to cycloheximide and inability to grow at the low temperature segregate together and thus appear to be effects of the same mutation. Since many cold-sensitive mutants of bacteria have been found to have altered ribosomes and since cycloheximide resistance in yeast can be caused by ribosomal changes, this suggests that the mutants having low-temperature-sensitive growth may be defective in ribosome-assembly processes at the low temperatures. Two of the lts loci, lts1 and lts3 have been located on chromosome VII and another two, lts4 and lts10 on chromosome IV. A mutation, cyh10, conferring cycloheximide resistance, but not cold sensitivity, has been located close to the centromere on chromosome II.

Singh, Arjun; Manney, T. R.

1974-01-01

349

Genetic analysis of mutations affecting growth of Saccharomyces cerevisiae at low temperature.  

PubMed

A large number of genes control growth of the yeast Saccharomyces cerevisiae at low temperatures (< 10 degrees ). Approximately 47 percent of the mutants selected for inability to grow at 4-5 degrees C show increased sensitivity to cycloheximide. In 3 of 4 cases tested, supersensitivity to cycloheximide and inability to grow at the low temperature segregate together and thus appear to be effects of the same mutation. Since many cold-sensitive mutants of bacteria have been found to have altered ribosomes and since cycloheximide resistance in yeast can be caused by ribosomal changes, this suggests that the mutants having low-temperature-sensitive growth may be defective in ribosome-assembly processes at the low temperatures. Two of the lts loci, lts1 and lts3 have been located on chromosome VII and another two, lts4 and lts10 on chromosome IV. A mutation, cyh10, conferring cycloheximide resistance, but not cold sensitivity, has been located close to the centromere on chromosome II. PMID:4371644

Singh, A; Manney, T R

1974-08-01

350

Alterations in S-adenosylhomocysteine metabolism decrease O6-methylguanine DNA methyltransferase gene expression without affecting promoter methylation.  

PubMed

The DNA repair enzyme O(6)-methylguanine DNA methyltransferase (MGMT) protects cells against the cytotoxic effects of alkylating agents. Therefore, modulation of MGMT expression in tumors is a possible strategy for improving the efficiency of cancer therapy. MGMT expression and activity is lost frequently in association with DNA hypermethylation of the MGMT promoter region. Since DNA and mRNA methylation are controlled by intracellular S-adenosylmethionine (AdoMet) and S-adenosylhomocysteine (AdoHcy) levels, we hypothesized a role for AdoMet/AdoHcy ratio in the regulation of MGMT promoter methylation and mRNA expression. Our initial studies showed that AdoMet/AdoHcy ratios vary over a wide range (7.0-50) in different glioblastoma and hepatoma cell lines. The studied cell lines exhibit distinct MGMT promoter methylation patterns: MGMT promoter was completely unmethylated in LN-18 and Tu 132 cells, hypermethylated in LN-229, U87-MG, and Tu 113 cells, and partially methylated in HepG2 cells. Furthermore, MGMT promoter methylation patterns and global DNA methylation are not related to intracellular AdoMet/AdoHcy ratio under control conditions. To lower AdoMet/AdoHcy ratio to values <1 we used AdoHcy hydrolase inhibitor adenosine-2',3'-dialdehyde (30 microM) and found that neither short-term (24 h) nor long-term changes (7 weeks) in AdoMet/AdoHcy ratio altered global or MGMT promoter methylation. However, experimentally elevated AdoHcy levels significantly decreased MGMT mRNA levels by >50% in all MGMT-expressing cell lines, which is most likely the result of impaired mRNA methylation. Thus, the present study suggests elevation of AdoHcy levels by AdoHcy hydrolase inhibition as a novel pharmacological approach to modulate MGMT expression and to increase the responsiveness to alkylating agents. PMID:18395186

Hermes, Marina; Geisler, Hermann; Osswald, Hartmut; Riehle, Renate; Kloor, Doris

2008-03-08

351

Identification of genetic alterations associated with the process of human experimental colon cancer liver metastasis in the nude mouse  

Microsoft Academic Search

Understanding the genetic elements controlling the process of tumor metastasis to distant organ sites such as the liver may be the key to improving survivorship from colon cancer. By using standard cytogenetic techniques in combination with comparative genomic hybridization, multiple genetic imbalances within three human colon cancer cell lines previously selected for differences in liver-metastatic behavior were identified. The entire

Timothy J. Yeatman; Michael L. Cher; Weiguang Mao; Marek Wloch; Thomas Tedesco

1996-01-01

352

Genetic and Environmental Factors Affecting the De Novo Appearance of the [Psi(+)] Prion in Saccharomyces Cerevisiae  

PubMed Central

It has previously been shown that yeast prion [PSI(+)] is cured by GuHCl, although reports on reversibility of curing were contradictory. Here we show that GuHCl treatment of both [PSI(+)] and [psi(-)] yeast strains results in two classes of [psi(-)] derivatives: Pin(+), in which [PSI(+)] can be reinduced by Sup35p overproduction, and Pin(-), in which overexpression of the complete SUP35 gene does not lead to the [PSI(+)] appearance. However, in both Pin(+) and Pin(-) derivatives [PSI(+)] is reinduced by overproduction of a short Sup35p N-terminal fragment, thus, in principle, [PSI(+)] curing remains reversible in both cases. Neither suppression nor growth inhibition caused by SUP35 overexpression in Pin(+) [psi(-)] derivatives are observed in Pin(-) [psi(-)] derivatives. Genetic analyses show that the Pin(+) phenotype is determined by a non-Mendelian factor, which, unlike the [PSI(+)] prion, is independent of the Sup35p N-terminal domain. A Pin(-) [psi(-)] derivative was also generated by transient inactivation of the heat shock protein, Hsp104, while [PSI(+)] curing by Hsp104 overproduction resulted exclusively in Pin(+) [psi(-)] derivatives. We hypothesize that in addition to the [PSI(+)] prion-determining domain in the Sup35p N-terminus, there is another self-propagating conformational determinant in the C-proximal part of Sup35p and that this second prion is responsible for the Pin(+) phenotype.

Derkatch, I. L.; Bradley, M. E.; Zhou, P.; Chernoff, Y. O.; Liebman, S. W.

1997-01-01

353

Environmental conditions affect spatial genetic structures and dispersal patterns in a solitary rodent.  

PubMed

The study of the spatial distribution of relatives in a population under contrasted environmental conditions provides critical insights into the flexibility of dispersal behaviour and the role of environmental conditions in shaping population relatedness and social structure. Yet few studies have evaluated the effects of fluctuating environmental conditions on relatedness structure of solitary species in the wild. The aim of this study was to determine the impact of interannual variations in environmental conditions on the spatial distribution of relatives [spatial genetic structure (SGS)] and dispersal patterns of a wild population of eastern chipmunks (Tamias striatus), a solitary rodent of North America. Eastern chipmunks depend on the seed of masting trees for reproduction and survival. Here, we combined the analysis of the SGS of adults with direct estimates of juvenile dispersal distance during six contrasted years with different dispersal seasons, population sizes and seed production. We found that environmental conditions influences the dispersal distances of juveniles and that male juveniles dispersed farther than females. The extent of the SGS of adult females varied between years and matched the variation in environmental conditions. In contrast, the SGS of males did not vary between years. We also found a difference in SGS between males and females that was consistent with male-biased dispersal. This study suggests that both the dispersal behaviour and the relatedness structure in a population of a solitary species can be relatively labile and change according to environmental conditions. PMID:23017101

Messier, Gabrielle Dubuc; Garant, Dany; Bergeron, Patrick; Réale, Denis

2012-09-27

354

'Faceness' and affectivity: Evidence for genetic contributions to distinct components of electrocortical response to human faces.  

PubMed

The ability to recognize a variety of different human faces is undoubtedly one of the most important and impressive functions of the human perceptual system. Neuroimaging studies have revealed multiple brain regions (including the FFA, STS, OFA) and electrophysiological studies have identified differing brain event-related potential (ERP) components (e.g., N170, P200) possibly related to distinct types of face information processing. To evaluate the heritability of ERP components associated with face processing, including N170, P200, and LPP, we examined ERP responses to fearful and neutral face stimuli in monozygotic (MZ) and dizygotic (DZ) twins. Concordance levels for early brain response indices of face processing (N170, P200) were found to be stronger for MZ than DZ twins, providing evidence of a heritable basis to each. These findings support the idea that certain key neural mechanisms for face processing are genetically coded. Implications for understanding individual differences in recognition of facial identity and the emotional content of faces are discussed. PMID:23769918

Shannon, Robert W; Patrick, Christopher J; Venables, Noah C; He, Sheng

2013-06-12

355

Genetic and Proteomic Analysis of Factors Affecting Serum Cholesterol Reduction by Lactobacillus acidophilus A4?  

PubMed Central

This article identifies novel factors involved in cholesterol reduction by probiotic bacteria, which were identified using genetic and proteomic approaches. Approximately 600 Lactobacillus acidophilus A4 mutants were created by random mutagenesis. The cholesterol-reducing ability of each mutant was determined and verified using two different methods: the o-phthalaldehyde assay and gas chromatographic analysis (GC). Among screened mutants, strain BA9 showed a dramatically diminished ability to reduce cholesterol, as demonstrated by a 7.7% reduction rate, while the parent strain had a more than 50% reduction rate. The transposon insertion site was mapped using inverse PCR (I-PCR), and it was determined using bioinformatic methods that the deleted region contained the Streptococcus thermophilus catabolite control protein A gene (ccpA). In addition, we have shown using two-dimensional gel electrophoresis (2-DE) that several proteins, including a transcription regulator, FMN-binding protein, major facilitator superfamily permease, glycogen phosphorylase, the YknV protein, and fructose/tagatose bisphosphate aldolase, were strongly regulated by the ccpA gene. In addition, in vivo experiments investigating ccpA function were conducted with rats. Rats fed wild-type L. acidophilus A4 showed a greater than 20% reduction in total serum cholesterol, but rats fed BA9 mutant L. acidophilus showed only an approximately 10% reduction in cholesterol. These results provide important insights into the mechanism by which these lactic acid bacteria reduce cholesterol.

Lee, Jin; Kim, Younghoon; Yun, Hyun Sun; Kim, Jong Gun; Oh, Sejong; Kim, Sae Hun

2010-01-01

356

Characterization and genetic mapping of a mutation affecting apurinic endonuclease activity in Staphylococcus aureus  

SciTech Connect

Protoplast fusion between the Rec- mutant RN981 (L. Wyman, R. V. Goering, and R. P. Novick, Genetics 76:681-702, 1974) of Staphylococcus aureus NCTC 8325 and a Rec+ NCTC 8325 derivative yielded Rec+ recombinants that exhibited the increased sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine characteristic of RN981. Transformation analyses identified a specific mutation, designated ngr-374, that was responsible not only for N-methyl-N'-nitro-N-nitrosoguanidine sensitivity, but also sensitivity to methyl methanesulfonate, ethyl methanesulfonate, nitrous acid, and UV irradiation. However, ngr-374-carrying recombinants showed no significant increase in their sensitivity to mitomycin C or 4-nitroquinoline 1-oxide and were unaffected in recombination proficiency. In vitro assays showed that ngr-374-carrying strains had lower apurinic/apyrimidinic endonuclease activities than the wild type. The chromosomal locus occupied by ngr-374 was shown to exist in the gene order omega(Chr::Tn551)40-ngr-374-thrB106.

Tam, J.E.; Pattee, P.A.

1986-11-01

357

Genetic factors affecting susceptibility to alcoholic liver disease in an Indian population.  

PubMed

Introduction. Indians are more likely to develop alcoholic cirrhosis compared to Caucasians, though the cause remains obscure. North Indians tend to consume more alcohol than other parts of the country. Genetic factors are likely to play a major role in these observations. This study investigated whether 10 different polymorphisms were associated with alcohol dependence and/or cirrhosis in North Indians. These were in ADH2*2 (rs1229984), ADH3*2 (rs698), CYP2E1*1D, CYP2E1*5 (rs3813867 and rs2031920), TNF-?(rs1800629), TNF-? (rs361525), IL-1? (rs3087258), CD-14 (rs2569190), IL-10 (rs1800872) and PNPLA3 (rs738409). Material and methods. Hundred healthy controls and 120 chronic alcoholics (60 alcoholic noncirrhotics and 60 alcoholic cirrhotics) attending various departments of PGIMER, Chandigarh were genotyped using PCR-RFLP methods. Results. Alcoholic cirrhotics compared to healthy individuals demonstrated a statistically significant increase in PNPLA3 (10109G) allele (p = 0.037, OR = 2.12, 95% CI 1.29-3.4). Rest of the associations were not significant after correction for multiple testing. Conclusion. PNPLA3 10109G predisposed North Indian subjects to alcoholic cirrhosis. PMID:24114820

Dutta, Atanu Kumar

358

Early maternal separation affects ethanol-induced conditioning in a nor-BNI insensitive manner, but does not alter ethanol-induced locomotor activity.  

PubMed

Early environmental stress significantly affects the development of offspring. This stress has been modeled in rats through the maternal separation (MS) paradigm, which alters the functioning of the HPA axis and can enhance ethanol intake at adulthood. Infant rats are sensitive to ethanol's reinforcing effects, which modulate ethanol seeking and intake. Little is known about the impact of MS on sensitivity to ethanol's appetitive and aversive effects during infancy. The present study assessed ethanol-induced conditioned place preference established through second-order conditioning (SOC), spontaneous or ethanol-induced locomotor activity and ethanol intake in preweanling rats that experienced normal animal facility rearing (AFR) or daily episodes of maternal separation (MS) during postnatal days 1-13 (PDs 1-13). Low-ethanol dose (0.5 g/kg) induced appetitive conditioned place preference (via SOC) in control rats given conventional rearing but not in rats given maternal separation in early infancy, whereas 2.0 g/kg ethanol induced aversive conditioned place preference in the former but not the latter. The administration of a kappa antagonist at PD 1 or immediately before testing did not alter ethanol-induced reinforcement. High (i.e., 2.5 and 2.0 g/kg) but not low (i.e., 0.5 g/kg) ethanol dose induced reliable motor stimulation, which was independent of early maternal separation. Ethanol intake and blood alcohol levels during conditioning were unaffected by rearing conditions. Pups given early maternal separation had lower body weights than controls and showed an altered pattern of exploration when placed in an open field. These results indicate that, when assessed in infant rats, earlier maternal separation alters the balance between the appetitive and aversive motivational effects of ethanol but has no effect on the motor activating effects of the drug. PMID:22108648

Pautassi, Ricardo Marcos; Nizhnikov, Michael E; Fabio, Ma Carolina; Spear, Norman E

2011-11-13

359

In Utero Activation of Fetal Memory T Cells Alters Host Regulatory Gene Expression and Affects HIV Susceptibility  

PubMed Central

In utero priming to malaria antigens renders cord blood mononuclear cells (CBMC) more susceptible to productive HIV infection in vitro in the absence of exogenous stimulation. This provides a unique model to better understand mechanisms affecting lymphocyte susceptibility to HIV infection in vivo. Effector memory CD3+CD4+ T cells (TEM) were the exclusive initial targets of HIV with rapid spread to central memory cells. HIV susceptibility correlated with increased expression of CD25 and HLA-DR on TEM. Virus entered all samples equally, however gag/pol RNA was only detected in HIV susceptible samples, suggesting regulation of proviral gene transcription. Targeted analysis of human genes in memory T cells showed greater expression of IFNG, NFATc1, IRF1, FOS, and PPIA and decreased expression YY1 and TFCP2 in HIV susceptible samples. Thus fetal priming to exogenous antigens enhances specific proviral gene transcription pathways in effector memory cells that may increase risk of vertical transmission of HIV.

Steiner, Kevin; Malhotra, Indu; Mungai, Peter; Muchiri, Eric; Dent, Arlene; King, Christopher L.

2013-01-01

360

Altered membrane lipid composition and functional parameters of circulating cells in cockles (Cerastoderma edule) affected by disseminated neoplasia.  

PubMed

Membrane lipid composition and morpho-functional parameters were investigated in circulating cells of the edible cockle (Cerastoderma edule) affected by disseminated neoplasia (neoplastic cells) and compared to those from healthy cockles (hemocytes). Membrane sterol levels, phospholipid (PL) class and subclass proportions and their respective fatty acid (FA) compositions were determined. Morpho-functional parameters were evaluated through total hemocyte count (THC), mortality rate, phagocytosis ability and reactive oxygen species (ROS) production. Both morpho-functional parameters and lipid composition were profoundly affected in neoplastic cells. These dedifferentiated cells displayed higher THC (5×), mortality rate (3×) and ROS production with addition of carbonyl cyanide m-chloro phenylhydrazone (1.7×) but lower phagocytosis ability (½×), than unaffected hemocytes. Total PL amounts were higher in neoplastic cells than in hemocytes (12.3 and 5.1 nmol×10(-6) cells, respectively). However, sterols and a particular subclass of PL (plasmalogens; 1-alkenyl-2-acyl PL) were present in similar amounts in both cell type membranes. This led to a two times lower proportion of these membrane lipid constituents in neoplastic cells when compared to hemocytes (20.5% vs. 42.1% of sterols in total membrane lipids and 21.7% vs. 44.2% of plasmalogens among total PL, respectively). Proportions of non-methylene interrupted FA- and 20:1n-11-plasmalogen molecular species were the most impacted in neoplastic cells when compared to hemocytes (?× and ¼×, respectively). These changes in response to this leukemia-like disease in bivalves highlight the specific imbalance of plasmalogens and sterols in neoplastic cells, in comparison to the greater stability of other membrane lipid components. PMID:23333874

Le Grand, Fabienne; Soudant, Philippe; Marty, Yanic; Le Goïc, Nelly; Kraffe, Edouard

2013-01-17

361

Genetic mapping of bra genes affecting branched-chain amino acid transport in Pseudomonas aeruginosa.  

PubMed

Pseudomonas aeruginosa PAO mutants defective in the transport systems for branched-chain amino acids were isolated and characterized. Two mutations in strains selected for trifluoroleucine resistance, braA300 and braB307, were mapped in the met-9020-dcu-9108 and the nar-9011-puuC10 region, respectively. The mutation loci in strains selected for azaleucine resistance, braC310 and bra-311 through bra-314, were all located near the fla genes, with an order of region I fla-bra-region II fla. Strains with braA300 showed a marked reduction in the high-affinity branched-chain amino acid transport system (LIV-I) and a considerable decrease in the lower-affinity system (LIV-II). Strains with braB307 were found to be defective in the LIV-II system. Strains selected for azaleucine resistance were all defective only in the LIV-I system and fell into three phenotypically distinct classes. Strains with braC310 produced a binding protein for leucine, isoleucine, valine, alanine, and threonine (LIVAT-BP) altered in binding ability, indicating that the braC gene is the structural one for the LIVAT-BP. Strains with bra-311 or bra-312 showed a complete loss of production of the LIVAT-BP. Strains with bra-313 or bra-314 produced normal levels of functional LIVAT-BP, suggesting that these mutations are located in a gene(s) other than braC. PMID:6402489

Hoshino, T; Tsuda, M; Iino, T; Nishio, K; Kageyama, M

1983-03-01

362

Mutant genetic background affects the functional rearrangement and kinetic properties of JMJD2b histone demethylase.  

PubMed

We have studied JMJD2b histone demethylase, which antagonizes H3K9me3 in the pericentromeric heterochromatin. In cells with a deficiency in the histone methyltransferase SUV39h, the level of full-length JMJD2b (JMJD2b-GFP-1086) at chromocenters was reduced, corresponding to a global decrease in JMJD2b and H3K9me3. In wild-type fibroblasts, the chromatin of ribosomal genes, which is dense with H3K9 methylation, lacked JMJD2b-GFP-1086, while mutant and truncated forms of JMJD2b densely occupied the nucleolar compartment. This implies that the PHD Zn-fingers and Tudor domains, which were removed in truncated JMJD2b, are responsible for the aberrant JMJD2b function. Intriguingly, the JMJD2b-GFP-1086 level was significantly higher in tumor cell nucleoli. The kinetic properties of JMJD2b-GFP-1086 in the nucleoli and nucleoplasm of normal and tumor cells were similar; ?50% recovery of prebleached intensity was reached after <1 s. However, the mobile fraction of JMJD2b-GFP-1086 was increased in SUV39h-deficient cells. Similarly, the mobile fractions of mutant JMJD2b(1-424)H189A-GFP and truncated JMJD2b(1-424)GFP were greater than that measured for the full-length protein. We suggest that nucleoli are the site of an aberrant function of JMJD2b, the kinetic properties of which can be influenced by a mutant genetic background. PMID:21073875

Bártová, Eva; Stixová, Lenka; Galiová, Gabriela; Harni?arová Horáková, Andrea; Legartová, So?a; Kozubek, Stanislav

2010-11-10

363

Genetic variation of serotonin receptor function affects prepulse inhibition of the startle.  

PubMed

Prepulse inhibition (PPI) is the attenuation of the startle response towards an instantaneous and intense stimulus when preceded by a weaker non-startling stimulus. Deficits in this sensorimotor gating process have been associated with the pathophysiology of schizophrenia and other psychiatric disorders. Among the neurotransmitters involved in PPI modulation, serotonin (5-HT) has so far received comparably little attention. While a recent pharmacological study suggests an important role of different 5-HT receptor (5-HTR) subtypes in PPI modulation, the mechanisms by which 5-HTR impact on PPI remain to be further elucidated. Therefore, we employed a molecular genetic approach in order to examine whether PPI is associated with two functional 5-HTR gene polymorphisms, 5-HTR1A C-1019G and 5-HTR2A T102C. In a sample of 81 healthy volunteers, we found no significant main effects of the polymorphisms, but a significant interaction effect on PPI at short (50 ms) and mid-long (150 ms) pulse-prepulse intervals. The presence of the 5-HTR2A T allele (reported to result in higher 5-HTR2A expression) led to attenuated PPI only in the absence of the 5-HTR1A G allele (reported to result in reduced 5-HTR1A autoreceptor expression). Our results may indicate that a higher 5-HTR2A expression together with a reduced 5-HTR1A autoreceptor expression and consequently, elevated firing rates of serotonergic neurons results in elevated 5-HTR2A activation by serotonin which could potently attenuate PPI. While further research into the molecular mechanisms underlying this interaction is needed, our results underscore the role of 5-HTR in PPI modulation and further implicate the 5-HTR1A G-1019C and the 5-HTR2A T102C polymorphisms in the pathophysiology of schizophrenia. PMID:19352591

Bräuer, David; Strobel, Alexander; Hensch, Tilman; Diers, Kersten; Lesch, Klaus-Peter; Brocke, Burkhard

2009-04-08

364

Mutations Affecting Cell Division in TETRAHYMENA PYRIFORMIS . I. Selection and Genetic Analysis  

PubMed Central

Fourteen nitrosoguanidine-induced mutations that bring about temperature-sensitive morphological abnormalities resulting from a specific effect on cell division have been isolated as heterozygous phenotypic assortants in Tetrahymena pyriformis syngen 1. Genetic analysis revealed all to be single-gene recessives. Detailed analysis of the kinetics of assortment for one of the mutated alleles revealed a rate (0.0104 pure lines per fission) consistent with that previously observed at other loci in this organism. The mutations fall into six complementation groups (mo1, mo2, mo3, mo6, mo8 , and mo12). Homozygotes of mo2 are unconditionally expressed, while all alleles of mo1, mo6, mo8, and mo12 are heat sensitive for division arrest. At the mo3 locus two alleles are heat sensitive, one is primarily cold sensitive, while two are sensitive to both heat and cold. Two out of three combinations of different mo3 alleles show conventional Mendelian segregation of conditions of expression. Different alleles of mo1, mo3, mo8, and mo12 also manifest differences in penetrance at the restrictive temperature. Despite these differences involving expression, the abnormal phenotypes themselves are locus-specific and distinctive; in the one case (mo1a and mo1 b) in which two alleles manifest somewhat different phenotypes, the F1 between them is intermediate. One additional recessive mutation (fat1) brings about a nonconditional lengthening of the cell cycle, with some arrest of cell division at the restrictive temperature. These findings demonstrate that selection of heterozygotes undergoing phenotypic assortment can be an effective method for obtaining substantial numbers of a desired class of temperature-sensitive mutations in T. pyriformis.

Frankel, Joseph; Jenkins, Leslie M.; Doerder, F. Paul; Nelsen, E. Marlo

1976-01-01

365

Nonsynonymous natural genetic polymorphisms in the bovine leptin gene affect biochemical and biological characteristics of the mature hormone.  

PubMed

Leptin (LEP) is a cytokine-like hormone proven to be involved in diverse biological processes. In livestock, it regulates feed intake, BW homeostasis, and energy balance, among other traits. Natural nonsynonymous genetic polymorphisms in the ovine leptin (oLEP) alter the biochemical and physiological characteristics of its gene products. Here we studied in vitro and in vivo the biochemical and physiological characteristics of recombinant hormones representing the oLEP and bovine leptin (bLEP) reference sequences of wild-type (WT) leptins (GenBank accession No. U84247 and U50365, respectively), oLEP and bLEP recombinant muteins carrying the R4C mutation, and oLEP recombinant hormones carrying the A59V and Q62R mutations, which were detected in bLEP. All proteins were purified to homogeneity as monomers and formed 1:1 molar ratio complexes with the chicken leptin-binding domain (LBD). Surface plasmon resonance experiments revealed that all protein variants exhibit reduced (P < 0.05) affinity to chicken (ch) and human (h) LBD compared with the WT oLEP and bLEP recombinant proteins. The ovine and bovine R4C muteins exhibited significantly (P < 0.05) greater induction of cell proliferation in a Baf/3 cell line bioassay, despite lower affinity toward both hLBD and chLBD. Intra-third cerebral ventricle infusion of oLEP and its 3 muteins in sheep resulted in reduced feed intake. However, the 3 tested muteins had a decreased (P < 0.05) inhibitory effect than the WT LEP. It was concluded that natural genetic polymorphisms in the bLEP are associated with variation in the biochemical and physiological properties of the protein. PMID:21926317

Reicher, S; Ramos-Nieves, J M; Hileman, S M; Boisclair, Y R; Gootwine, E; Gertler, A

2011-09-16

366

Regulation of Enzyme Activities in Drosophila: Genetic Variation Affecting Induction of Glucose 6-Phosphate and 6-Phosphogluconate Dehydrogenases in Larvae  

PubMed Central

The genetic basis of modulation by dietary sucrose of the enzyme activities glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities in third instar larvae of Drosophila melanogaster was investigated, using isogenic lines derived from wild populations. Considerable genetically determined variation in response was detected among lines that differed only in their third chromosome constitution. Comparison of crossreacting material between a responding and a nonresponding line showed that the G6PD activity variation is due to changes in G6PD protein level. These differences in responses are localized in the fat body, with 300 m m sucrose in the diet resulting in a sixfold stimulation of G6PD activity and a fourfold one of 6PGD in the line showing the strongest response. In this tissue, the responses of the two enzymes are closely correlated with one another. Using recombinant lines, we obtained data that suggested the existence of more than one gene on chromosome III involved in the regulation of G6PD in the fat body, and at least one of these genes affects the level of 6PGD as well.

Cochrane, Bruce J.; Lucchesi, John C.; Laurie-Ahlberg, C. C.

1983-01-01

367

Ghrelin and measures of satiety are altered in polycystic ovary syndrome but not differentially affected by diet composition.  

PubMed

Background - Polycystic ovary syndrome (PCOS) is a common endocrine condition in women of reproductive age. In subjects with PCOS, there may be dysregulation of ghrelin, a hormone implicated in appetite regulation. The effect of varying dietary composition on ghrelin is unclear. Objective - To examine the effects of PCOS status and varying diet composition on ghrelin homeostasis and subjective measures of satiety and hunger. Design - Overweight BMI-matched women (BMI 35.4 +/-0.9 kgm(-2)) followed a standard protein (55% carbohydrate, 15% protein) (n = 10 PCOS, n = 6 non-PCOS) or high protein diet (40% carbohydrate, 30% protein) (n =10 PCOS, n = 5 non-PCOS) for 12 weeks of weight loss (about 6000 kJ/day) and 4 weeks of energy balance. Post-prandial ghrelin and measures of hunger and satiety by visual analogue scores (VAS) were assessed after a representative meal tolerance test (MTT). Outcomes - Diet composition had no effect on ghrelin or VAS measures. Non-PCOS subjects had a 70% higher fasting baseline ghrelin (P = 0.011) and a greater increase in fasting ghrelin (57.5% vs 34.0%, P = 0.033) and a greater maximal decrease in MTT ghrelin with weight loss (-42.7 +/- 17.3 vs -8.5 +/- 4.1 pM, P=0.02) than subjects with PCOS. Subjects with PCOS were more hungry (P =0.001) and less satiated (P = 0.007) at week 0 and 16 than non-PCOS subjects. Conclusions - Ghrelin homeostasis and measures of hunger and satiety are significantly impaired in subjects with PCOS but not affected by diet composition. PMID:15023670

Moran, L J; Noakes, M; Clifton, P M; Wittert, G; Tomlinson, L; Galletly, C; Luscombe, N; Tomlinson, L; Norman, R J

2003-01-01

368

Amphotericin B severely affects expression and activity of the endothelial constitutive nitric oxide synthase involving altered mRNA stability  

PubMed Central

The therapeutic use of the antifungal drug amphotericin B (AmB) is limited due to severe side effects like glomerular vasoconstriction and risk of renal failure during AmB administration. As nitric oxide (NO) has substantial functions in renal autoregulation, we have determined the effects of AmB on endothelial constitutive NO synthase (ecNOS) expression and activity in human and rat endothelial cell cultures.AmB used at concentrations of 0.6 to 1.25??g?ml?1 led to increases in ecNOS mRNA and protein expression as well as NO production. This was the result of an increased ecNOS mRNA half-life. In contrast, incubation of cells with higher albeit subtoxic concentrations of AmB (2.5–5.0??g?ml?1) resulted in a decrease or respectively in completely abolished ecNOS mRNA and protein expression with a strongly reduced or inhibited ecNOS activity, due to a decrease of ecNOS mRNA half-life. None of the AmB concentrations affected promoter activity as found with a reporter gene construct stably transfected into ECV304 cells.Thus, our experiments show a concentration-dependent biphasic effect of AmB on expression and activity of ecNOS, an effect best explained by AmB influencing ecNOS mRNA stability. In view of the known renal accumulation of this drug the results reported here could help to elucidate its renal toxicity.

Suschek, Christoph Viktor; Bonmann, Eckhard; Kleinert, Hartmut; Wenzel, Michael; Mahotka, Csaba; Kolb, Hubert; Forstermann, Ulrich; Gerharz, Claus-Dieter; Kolb-Bachofen, Victoria

2000-01-01

369

Antioxidant capacity and phenolic content of spinach as affected by genetics and growing season.  

PubMed

Total phenolic content and antioxidant capacity of 11 commercial cultivars and 15 advanced breeding lines of spinach were determined over two growing seasons known to vary in biotic and abiotic stresses. Flavonoid composition and content of fall-grown commercial cultivars and advanced breeding lines were also determined. Over-winter spinach, which was planted in late fall and harvested in the spring, had much higher levels of total phenolics and antioxidant capacity than spinach planted in early fall and harvested in late fall, indicating that growing conditions, as well as biotic and abiotic stresses, influenced phenolic metabolism. Genotype also appeared to play an important role in affecting phenolic metabolism and antioxidant capacity in spinach. Advanced breeding lines of spinach, which show increased disease resistance, had higher levels of total phenolics, individual and total flavonoids, and antioxidant capacity than commercial cultivars. Our results indicate that plant breeders can select for increased phenolic content to increase antioxidant capacity in spinach cultivars, or the crops can be grown in different seasons or under certain stress conditions to elevate levels of antioxidants. PMID:12358455

Howard, L R; Pandjaitan, N; Morelock, T; Gil, M I

2002-10-01

370

Genetic factors affecting the impact of DNA polymerase delta proofreading activity on mutation avoidance in yeast.  

PubMed Central

Base selectivity, proofreading, and postreplication mismatch repair are important for replication fidelity. Because proofreading plays an important role in error correction, we have investigated factors that influence its impact in the yeast Saccharomyces cerevisiae. We have utilized a sensitive mutation detection system based on homonucleotide runs of 4 to 14 bases to examine the impact of DNA polymerase delta proofreading on mutation avoidance. The contribution of DNA polymerase delta proofreading on error avoidance was found to be similar to that of DNA polymerase epsilon proofreading in short homonucleotide runs (A4 and A5) but much greater than the contribution of DNA polymerase epsilon proofreading in longer runs. We have identified an intraprotein interaction affecting mutation prevention that results from mutations in the replication and the proofreading regions, resulting in an antimutator phenotype relative to a proofreading defect. Finally, a diploid strain with a defect in DNA polymerase delta proofreading exhibits a higher mutation rate than a haploid strain. We suggest that in the diploid population of proofreading defective cells there exists a transiently hypermutable fraction that would be inviable if cells were haploids.

Tran, H T; Degtyareva, N P; Gordenin, D A; Resnick, M A

1999-01-01

371

Genetic and management factors affecting beef quality in grazing Hereford steers.  

PubMed

Attributes contributing to differences in beef quality of 206 Hereford steers finished on pasture were assessed. Beef quality traits evaluated were: Warner-Bratzler meat tenderness and muscle and fat color at one and seven days after slaughter and trained sensory panel traits (tenderness, juiciness, flavor, and marbling) at seven days. Molecular markers were CAPN1 316 and an SNP in exon 2 on the leptin gene (E2FB). Average daily live weight gain, ultrasound monthly backfat thickness gain and rib-eye area gain were estimated. Molecular markers effects on meat quality traits were analyzed by mixed models. Association of meat quality with post weaning growth traits was analyzed by canonical correlations. Muscle color and marbling were affected by CAPN1 316 and E2FB and Warner-Bratzler meat tenderness by the former. The results confirm that marker assisted selection for tenderness is advisable only when beef aging is a common practice. The most important sources of variation in tenderness and color of meat remained unaccounted for. PMID:22818350

Melucci, L M; Panarace, M; Feula, P; Villarreal, E L; Grigioni, G; Carduza, F; Soria, L A; Mezzadra, C A; Arceo, M E; Papaleo Mazzucco, J; Corva, P M; Irurueta, M; Rogberg-Muñoz, A; Miquel, M C

2012-06-29

372

Does the reproductive strategy affect the transmission and genetic diversity of bionts in cyanolichens? A case study using two closely related species.  

PubMed

Observed levels of population genetic diversity are often associated with differences in species dispersal and reproductive strategies. In symbiotic organisms, the genetic diversity level of each biont should also be highly influenced by biont transmission. In this study, we evaluated the influence of the reproductive strategies of cyanolichen species on the current levels of population genetic diversity of bionts. To eliminate any phylogenetic noise, we selected two closely related species within the genus Degelia, which only differ in their reproductive systems. We sampled all known populations of both species in central Spain and genotyped the fungal and cyanobacterial components of lichen samples using DNA sequences as molecular markers. We applied population genetics approaches to evaluate the genetic diversity and population genetic structure of the symbiotic components of both lichen species. Our results indicate that fungal and cyanobiont genetic diversity is highly influenced by the reproductive systems of lichen fungus. We detected higher bionts genetic diversity values in the sexual species Degelia plumbea. By contrast, the levels of fungal and cyanobiont genetic diversity in the asexual species Degelia atlantica were extremely low (almost clonal), and the species shows a high specificity towards its cyanobiont. Our results indicate that reproduction by vegetative propagules, in species of the genus Degelia, favors vertical transmission and clonality, which affects the species' capacity for resources and competition, thereby limiting the species to restricted niches. PMID:23184157

Otálora, Mónica A G; Salvador, Clara; Martínez, Isabel; Aragón, Gregorio

2012-11-27

373

Genetic characterization of healthy and sebaceous adenitis affected Standard Poodles from the United States and the United Kingdom.  

PubMed

The degree of heterogeneity associated with geographic origin and sebaceous adenitis (SA) status in Standard Poodles from the United States (US) and the United Kingdom (UK) was assessed. Healthy and SA-affected Standard Poodles from the US and the UK shared a major mitochondrial DNA (mtDNA) haplotype and a single Y chromosome haplotype. However, minor mtDNA haplotypes and frequencies were somewhat different between US and UK dogs and were significantly less associated with SA than major haplotypes across both populations. The US and UK populations exhibited recent divergence from a common gene pool, based on allele frequencies of 24 highly polymorphic short tandem repeats and principle coordinates and cluster analyses of genotype frequencies. However, there was no differentiation between SA affected and unaffected dogs. Over 90% of US and UK Poodles shared a common dog leukocyte antigen (DLA) class II haplotype, but showed some differentiation in minor haplotype frequency. No difference was observed in haplotype heterozygosity between SA affected and unaffected dogs from the same country and no disease association for SA was found within the DLA region by a high density single nucleotide polymorphism (SNP) scan. Zygosity mapping in the DLA region of Poodles indicated much lower site-specific diversity than in an outbred population of street dogs from Bali, Indonesia, reflecting the degree that breed associated historical bottlenecks have reduced diversity in a polymorphic region of the genome. This study shows possible pitfalls in more extensive genome-wide association studies, such as case and control numbers, population stratification, the involvement of multiple genes, and/or the possibility that SA susceptibility is fixed or nearly fixed within the breed, which can reduce power to detect genetic associations. PMID:22512808

Pedersen, N C; Liu, H; McLaughlin, B; Sacks, B N

2012-04-18

374

Ribosomal suppressors and antisuppressors in Podospora anserina: Altered susceptibility to paromomycin and relationships between genetic and phenotypic suppression  

Microsoft Academic Search

Informational suppressors and antisuppressors have been previously isolated in Podospora anserina, and their properties suggest that they could be ribosomal mutants involved in the control of translational fidelity. In this paper we present results concerning relationships between these mutants and paromomycin, an aminoglycoside antibiotic known to stimulate translational errors. The mutants were found to manifest an altered growth sensitivity to

E. Coppin-Raynal

1981-01-01

375

Genetic and Chemical Reductions in Protein Phosphatase Activity Alter Auxin Transport, Gravity Response, and Lateral Root Growth  

Microsoft Academic Search

Auxin transport is required for important growth and developmental processes in plants, including gravity response and lateral root growth. Several lines of evidence suggest that reversible protein phosphorylation regulates auxin transport. Arabidopsis rcn1 mutant seedlings exhibit reduced protein phosphatase 2A activity and defects in differen- tial cell elongation. Here we report that reduced phosphatase activity alters auxin transport and dependent

Aaron M. Rashotte; Alison DeLong; Gloria K. Muday

2001-01-01

376

Biochemical and genetic studies on two different types of erythromycin resistant mutants of Escherichia coli with altered ribosomal proteins  

Microsoft Academic Search

Ribosomes from nine E. coli mutants with high level resistance to the antibiotic erythromycin were isolated and their proteins were compared with those of the parental strains by two-dimensional polyacrylamide gel electrophoresis, by carboxymethylcellulose column chromatography and by immunological techniques. Two 50S proteins were found to be altered in the mutants: either L 4 or L 22.

H. G. Wittmann; G. Stöffler; D. Apirion; L. Rosen; K. Tanaka; M. Tamaki; R. Takata; S. Dekio; E. Otaka; S. Osawa

1973-01-01

377

Genetics.  

PubMed

The present state of knowledge on the genetics of anxiety disorders, in particular panic disorder, comprising clinical and molecular genetic studies, interaction analyses, as well as meta-analyses of single association studies will be presented in detail. A particular focus will be on the most robust findings in panic disorder to date in the serotonergic, noradrenergic, and dopaminergic system, such as the catechol-O-methyltransferase (COMT) gene. Additionally, findings on the adenosine receptor 2A (A2A) gene, which has been reported to be associated with panic disorder and also with anxiety levels after caffeine administration in a gene--environment interactional model, will be discussed. Furthermore, the first imaging genetic findings in panic disorder, social phobia, and anxiety-related traits using fMRI and PET techniques in combination with molecular genetic association analyses are reviewed, taking into account the present intermediate phenotype discussion in the investigation of complex genetic disorders. Finally, the first exemplary pharmacogenetic studies in panic disorder and generalized social phobia will be presented. The pathomechanism of anxiety disorders and in particular panic disorder is considered to be multifactorial with converging evidence for a pivotal role of genetic factors in particular, which will be presented in detail in this chapter. PMID:21309106

Domschke, Katharina; Deckert, Jürgen

2010-01-01

378

Genetic Variation at the Phospholipid Transfer Protein Locus Affects Its Activity and High-Density Lipoprotein Size and Is a Novel Marker of Cardiovascular Disease Susceptibility  

Microsoft Academic Search

Background-In contrast to clear associations between variants in genes participating in low-density lipoprotein metabolism and cardiovascular disease risk, such associations for high-density lipoprotein (HDL)-related genes are not well supported by recent large studies. We aimed to determine whether genetic variants at the locus encoding phospholipid transfer protein (PLTP), a protein involved in HDL remodeling, underlie altered PLTP activity, HDL particle

M. Vergeer; S. M. Boekholdt; M. S. Sandhu; S. L. Ricketts; N. J. Wareham; M. J. Brown; U. de Faire; K. Leander; B. Gigante; M. Kavousi; A. Hofman; A. G. Uitterlinden; Duijn van C. M; J. C. M. Witteman; J. W. Jukema; E. E. Schadt; E. van der Schoot; J. J. P. Kastelein; K.-T. Khaw; R. P. F. Dullaart; A. van Tol; M. D. Trip; G. M. Dallinga-Thie

2010-01-01

379

Genetic alterations in a primary medullary thyroid carcinoma and its lymph node metastasis in a patient with 15 years follow-up  

PubMed Central

Background Association between DNA alterations and clinical parameters as recurrence, survival or prognosis has been found in a variety of tumors. A clear association between Medullary Thyroid Carcinoma (MTC) and RET oncogene mutation has been accepted. Specifically M918T RET mutation represents the main genetic event in most cases of sporadic MTC (SMTC) and limited chromosomal alterations analyses have been performed. Methods In the present work, a comparative genomic hybridization (CGH) study was performed using DNA from a primary tumor in a M918T RET mutation-positive SMTC patient and f