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1

Characterization of paralogous protein families in rice  

PubMed Central

Background High gene numbers in plant genomes reflect polyploidy and major gene duplication events. Oryza sativa, cultivated rice, is a diploid monocotyledonous species with a ~390 Mb genome that has undergone segmental duplication of a substantial portion of its genome. This, coupled with other genetic events such as tandem duplications, has resulted in a substantial number of its genes, and resulting proteins, occurring in paralogous families. Results Using a computational pipeline that utilizes Pfam and novel protein domains, we characterized paralogous families in rice and compared these with paralogous families in the model dicotyledonous diploid species, Arabidopsis thaliana. Arabidopsis, which has undergone genome duplication as well, has a substantially smaller genome (~120 Mb) and gene complement compared to rice. Overall, 53% and 68% of the non-transposable element-related rice and Arabidopsis proteins could be classified into paralogous protein families, respectively. Singleton and paralogous family genes differed substantially in their likelihood of encoding a protein of known or putative function; 26% and 66% of singleton genes compared to 73% and 96% of the paralogous family genes encode a known or putative protein in rice and Arabidopsis, respectively. Furthermore, a major skew in the distribution of specific gene function was observed; a total of 17 Gene Ontology categories in both rice and Arabidopsis were statistically significant in their differential distribution between paralogous family and singleton proteins. In contrast to mammalian organisms, we found that duplicated genes in rice and Arabidopsis tend to have more alternative splice forms. Using data from Massively Parallel Signature Sequencing, we show that a significant portion of the duplicated genes in rice show divergent expression although a correlation between sequence divergence and correlation of expression could be seen in very young genes. Conclusion Collectively, these data suggest that while co-regulation and conserved function are present in some paralogous protein family members, evolutionary pressures have resulted in functional divergence with differential expression patterns. PMID:18284697

Lin, Haining; Ouyang, Shu; Egan, Amy; Nobuta, Kan; Haas, Brian J; Zhu, Wei; Gu, Xun; Silva, Joana C; Meyers, Blake C; Buell, C Robin

2008-01-01

2

Adaptive mutations that prevent crosstalk enable the expansion of paralogous signaling protein families.  

PubMed

Orthologous proteins often harbor numerous substitutions, but whether these differences result from neutral or adaptive processes is usually unclear. To tackle this challenge, we examined the divergent evolution of a model bacterial signaling pathway comprising the kinase PhoR and its cognate substrate PhoB. We show that the specificity-determining residues of these proteins are typically under purifying selection but have, in ?-proteobacteria, undergone a burst of diversification followed by extended stasis. By reversing mutations that accumulated in an ?-proteobacterial PhoR, we demonstrate that these substitutions were adaptive, enabling PhoR to avoid crosstalk with a paralogous pathway that arose specifically in ?-proteobacteria. Our findings demonstrate that duplication and the subsequent need to avoid crosstalk strongly influence signaling protein evolution. These results provide a concrete example of how system-wide insulation can be achieved postduplication through a surprisingly limited number of mutations. Our work may help explain the apparent ease with which paralogous protein families expanded in all organisms. PMID:22770222

Capra, Emily J; Perchuk, Barrett S; Skerker, Jeffrey M; Laub, Michael T

2012-07-01

3

Identifying Cognate Binding Pairs among a Large Set of Paralogs: The Case of PE\\/PPE Proteins of Mycobacterium tuberculosis  

Microsoft Academic Search

We consider the problem of how to detect cognate pairs of proteins that bind when each belongs to a large family of paralogs. To illustrate the problem, we have undertaken a genomewide analysis of interactions of members of the PE and PPE protein families of Mycobacterium tuberculosis. Our computational method uses structural information, operon organization, and protein coevolution to infer

Robert Riley; Matteo Pellegrini; David Eisenberg

2008-01-01

4

Parameters of proteome evolution from histograms of amino-acid sequence identities of paralogous proteins  

E-print Network

The evolution of the full repertoire of proteins encoded in a given genome is mostly driven by gene duplications, deletions, and sequence modifications of existing proteins. Indirect information about relative rates and other intrinsic parameters of these three basic processes is contained in the proteome-wide distribution of sequence identities of pairs of paralogous proteins. We introduce a simple mathematical framework based on a stochastic birth-and-death model that allows one to extract some of this information and apply it to the set of all pairs of paralogous proteins in seven model organisms. It was found that the histogram of sequence identities p generated by an all-to-all alignment of all protein sequences encoded in a genome is well fitted with a power-law form ~p^(-gamma) with the value of the exponent gamma around 4 for the majority of organisms used in this study. This implies that the intra-protein variability of substitution rates is best described by the Gamma-distribution with the exponent alpha ~ 0.33. We separately measure the short-term (``raw'') duplication and deletion rates r*_dup, r*_del which include gene copies that will be removed soon after the duplication event and their dramatically reduced long-term counterparts r_dup, r_del. Systematic trends of each of the four duplication/deletion rates with the total number of genes in the genome were analyzed. All but the deletion rate of recent duplicates r*_del were shown to systematically increase with N_genes. Abnormally flat shapes of sequence identity histograms observed for yeast and human are consistent with lineages leading to these organisms undergoing one or more whole-genome duplications.

Jacob Bock Axelsen; Koon-Kiu Yan; Sergei Maslov

2005-07-21

5

Protein Phosphatase 1 ? Paralogs Encode the Zebrafish Myosin Phosphatase Catalytic Subunit  

PubMed Central

Background The myosin phosphatase is a highly conserved regulator of actomyosin contractility. Zebrafish has emerged as an ideal model system to study the in vivo role of myosin phosphatase in controlling cell contractility, cell movement and epithelial biology. Most work in zebrafish has focused on the regulatory subunit of the myosin phosphatase called Mypt1. In this work, we examined the critical role of Protein Phosphatase 1, PP1, the catalytic subunit of the myosin phosphatase. Methodology/Principal Findings We observed that in zebrafish two paralogous genes encoding PP1?, called ppp1cba and ppp1cbb, are both broadly expressed during early development. Furthermore, we found that both gene products interact with Mypt1 and assemble an active myosin phosphatase complex. In addition, expression of this complex results in dephosphorylation of the myosin regulatory light chain and large scale rearrangements of the actin cytoskeleton. Morpholino knock-down of ppp1cba and ppp1cbb results in severe defects in morphogenetic cell movements during gastrulation through loss of myosin phosphatase function. Conclusions/Significance Our work demonstrates that zebrafish have two genes encoding PP1?, both of which can interact with Mypt1 and assemble an active myosin phosphatase. In addition, both genes are required for convergence and extension during gastrulation and correct dosage of the protein products is required. PMID:24040418

Jayashankar, Vaishali; Nguyen, Michael J.; Carr, Brandon W.; Zheng, Dale C.; Rosales, Joseph B.; Rosales, Joshua B.; Weiser, Douglas C.

2013-01-01

6

Characterization of fragile X mental retardation protein recruitment and dynamics in Drosophila stress granules.  

PubMed

The RNA-binding protein Fragile X Mental Retardation (FMRP) is an evolutionarily conserved protein that is particularly abundant in the brain due to its high expression in neurons. FMRP deficiency causes fragile X mental retardation syndrome. In neurons, FMRP controls the translation of target mRNAs in part by promoting dynamic transport in and out neuronal RNA granules. We and others have previously shown that upon stress, mammalian FMRP dissociates from translating polysomes to localize into neuronal-like granules termed stress granules (SG). This localization of FMRP in SG is conserved in Drosophila. Whether FMRP plays a key role in SG formation, how FMRP is recruited into SG, and whether its association with SG is dynamic are currently unknown. In contrast with mammalian FMRP, which has two paralog proteins, Drosophila FMR1 (dFMRP) is encoded by a single gene that has no paralog. Using this genetically simple model, we assessed the role of dFMRP in SG formation and defined the determinants required for its recruitment in SG as well as its dynamics in SG. We show that dFMRP is dispensable for SG formation in vitro and ex vivo. FRAP experiments showed that dFMRP shuttles in and out SG. The shuttling activity of dFMRP is mediated by a protein-protein interaction domain located at the N-terminus of the protein. This domain is, however, dispensable for the localization of dFMRP in SG. This localization of dFMRP in SG requires the KH and RGG motifs which are known to mediate RNA binding, as well as the C-terminal glutamine/asparagine rich domain. Our studies thus suggest that the mechanisms controlling the recruitment of FMRP into SG and those that promote its shuttling between granules and the cytosol are uncoupled. To our knowledge, this is the first demonstration of the regulated shuttling activity of a SG component between RNA granules and the cytosol. PMID:23408971

Gareau, Cristina; Houssin, Elise; Martel, David; Coudert, Laetitia; Mellaoui, Samia; Huot, Marc-Etienne; Laprise, Patrick; Mazroui, Rachid

2013-01-01

7

Characterization of Fragile X Mental Retardation Protein Recruitment and Dynamics in Drosophila Stress Granules  

PubMed Central

The RNA-binding protein Fragile X Mental Retardation (FMRP) is an evolutionarily conserved protein that is particularly abundant in the brain due to its high expression in neurons. FMRP deficiency causes fragile X mental retardation syndrome. In neurons, FMRP controls the translation of target mRNAs in part by promoting dynamic transport in and out neuronal RNA granules. We and others have previously shown that upon stress, mammalian FMRP dissociates from translating polysomes to localize into neuronal-like granules termed stress granules (SG). This localization of FMRP in SG is conserved in Drosophila. Whether FMRP plays a key role in SG formation, how FMRP is recruited into SG, and whether its association with SG is dynamic are currently unknown. In contrast with mammalian FMRP, which has two paralog proteins, Drosophila FMR1 (dFMRP) is encoded by a single gene that has no paralog. Using this genetically simple model, we assessed the role of dFMRP in SG formation and defined the determinants required for its recruitment in SG as well as its dynamics in SG. We show that dFMRP is dispensable for SG formation in vitro and ex vivo. FRAP experiments showed that dFMRP shuttles in and out SG. The shuttling activity of dFMRP is mediated by a protein-protein interaction domain located at the N-terminus of the protein. This domain is, however, dispensable for the localization of dFMRP in SG. This localization of dFMRP in SG requires the KH and RGG motifs which are known to mediate RNA binding, as well as the C-terminal glutamine/asparagine rich domain. Our studies thus suggest that the mechanisms controlling the recruitment of FMRP into SG and those that promote its shuttling between granules and the cytosol are uncoupled. To our knowledge, this is the first demonstration of the regulated shuttling activity of a SG component between RNA granules and the cytosol. PMID:23408971

Gareau, Cristina; Houssin, Elise; Martel, David; Coudert, Laetitia; Mellaoui, Samia; Huot, Marc-Etienne; Laprise, Patrick; Mazroui, Rachid

2013-01-01

8

Targeted Identification of SUMOylation Sites in Human Proteins Using Affinity Enrichment and Paralog-specific Reporter Ions*  

PubMed Central

Protein modification by small ubiquitin-like modifier (SUMO) modulates the activities of numerous proteins involved in different cellular functions such as gene transcription, cell cycle, and DNA repair. Comprehensive identification of SUMOylated sites is a prerequisite to determine how SUMOylation regulates protein function. However, mapping SUMOylated Lys residues by mass spectrometry (MS) is challenging because of the dynamic nature of this modification, the existence of three functionally distinct human SUMO paralogs, and the large SUMO chain remnant that remains attached to tryptic peptides. To overcome these problems, we created HEK293 cell lines that stably express functional SUMO paralogs with an N-terminal His6-tag and an Arg residue near the C terminus that leave a short five amino acid SUMO remnant upon tryptic digestion. We determined the fragmentation patterns of our short SUMO remnant peptides by collisional activation and electron transfer dissociation using synthetic peptide libraries. Activation using higher energy collisional dissociation on the LTQ-Orbitrap Elite identified SUMO paralog-specific fragment ions and neutral losses of the SUMO remnant with high mass accuracy (< 5 ppm). We exploited these features to detect SUMO modified tryptic peptides in complex cell extracts by correlating mass measurements of precursor and fragment ions using a data independent acquisition method. We also generated bioinformatics tools to retrieve MS/MS spectra containing characteristic fragment ions to the identification of SUMOylated peptide by conventional Mascot database searches. In HEK293 cell extracts, this MS approach uncovered low abundance SUMOylated peptides and 37 SUMO3-modified Lys residues in target proteins, most of which were previously unknown. Interestingly, we identified mixed SUMO-ubiquitin chains with ubiquitylated SUMO proteins (K20 and K32) and SUMOylated ubiquitin (K63), suggesting a complex crosstalk between these two modifications. PMID:23750026

Lamoliatte, Frederic; Bonneil, Eric; Durette, Chantal; Caron-Lizotte, Olivier; Wildemann, Dirk; Zerweck, Johannes; Wenshuk, Holger; Thibault, Pierre

2013-01-01

9

ZP Domain Proteins in the Abalone Egg Coat Include a Paralog of VERL under Positive Selection That Binds Lysin and 18-kDa Sperm Proteins  

PubMed Central

Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and egg proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of proteins in the abalone egg VE. We expand 3-fold the number of known ZP domain proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous egg VE proteins bind a similar set of sperm proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm–egg fusion. This work identifies an egg coat paralog of VERL under positive selection and the candidate sperm proteins with which it may interact during abalone fertilization. PMID:19767347

Aagaard, Jan E.; Vacquier, Victor D.; MacCoss, Michael J.; Swanson, Willie J.

2010-01-01

10

Characterization of Fragile X Mental Retardation Protein granules formation and dynamics in Drosophila  

PubMed Central

Summary FMRP is an evolutionarily conserved protein that is highly expressed in neurons and its deficiency causes fragile X mental retardation syndrome. FMRP controls the translation of target mRNAs in part by promoting their dynamic transport in neuronal RNA granules. We have previously shown that high expression of mammalian FMRP induces formation of granules termed FMRP granules. These RNA granules are reminiscent of neuronal granules, of stress granules, as well as of the recently described in vitro-assembled granules. In contrast with mammalian FMRP, which has two paralog proteins, Drosophila FMRP (dFMRP) is encoded by a single gene that has no paralog. Using this genetically simple organism, we investigated formation and dynamics of FMRP granules. We found that increased expression of dFMRP in Drosophila cells induces the formation of dynamic dFMRP RNA granules. Mutagenesis studies identified the N-terminal protein–protein domain of dFMRP as a key determinant for FMRP granules formation. The RGG RNA binding motif of dFMRP is dispensable for dFMRP granules formation since its deletion does not prevent formation of those granules. Deletion of the RGG motif reduced, however, dFMRP trafficking between FMRP granules and the cytosol. Similarly, deletion of a large part of the KH RNA binding motif of dFMRP had no effect on formation of dFMRP-granules, but diminished the shuttling activity of dFMRP. Our results thus suggest that the mechanisms controlling formation of RNA granules and those promoting their dynamics are uncoupled. This study opens new avenues to further elucidate the molecular mechanisms controlling FMRP trafficking with its associated mRNAs in and out of RNA granules. PMID:23336078

Gareau, Cristina; Martel, David; Coudert, Laetitia; Mellaoui, Samia; Mazroui, Rachid

2013-01-01

11

Characterization of Fragile X Mental Retardation Protein granules formation and dynamics in Drosophila.  

PubMed

FMRP is an evolutionarily conserved protein that is highly expressed in neurons and its deficiency causes fragile X mental retardation syndrome. FMRP controls the translation of target mRNAs in part by promoting their dynamic transport in neuronal RNA granules. We have previously shown that high expression of mammalian FMRP induces formation of granules termed FMRP granules. These RNA granules are reminiscent of neuronal granules, of stress granules, as well as of the recently described in vitro-assembled granules. In contrast with mammalian FMRP, which has two paralog proteins, Drosophila FMRP (dFMRP) is encoded by a single gene that has no paralog. Using this genetically simple organism, we investigated formation and dynamics of FMRP granules. We found that increased expression of dFMRP in Drosophila cells induces the formation of dynamic dFMRP RNA granules. Mutagenesis studies identified the N-terminal protein-protein domain of dFMRP as a key determinant for FMRP granules formation. The RGG RNA binding motif of dFMRP is dispensable for dFMRP granules formation since its deletion does not prevent formation of those granules. Deletion of the RGG motif reduced, however, dFMRP trafficking between FMRP granules and the cytosol. Similarly, deletion of a large part of the KH RNA binding motif of dFMRP had no effect on formation of dFMRP-granules, but diminished the shuttling activity of dFMRP. Our results thus suggest that the mechanisms controlling formation of RNA granules and those promoting their dynamics are uncoupled. This study opens new avenues to further elucidate the molecular mechanisms controlling FMRP trafficking with its associated mRNAs in and out of RNA granules. PMID:23336078

Gareau, Cristina; Martel, David; Coudert, Laetitia; Mellaoui, Samia; Mazroui, Rachid

2013-01-15

12

Charge dependent retardation of amyloid ? aggregation by hydrophilic proteins.  

PubMed

The aggregation of amyloid ? peptides (A?) into amyloid fibrils is implicated in the pathology of Alzheimer's disease. In light of the increasing number of proteins reported to retard A? fibril formation, we investigated the influence of small hydrophilic model proteins of different charge on A? aggregation kinetics and their interaction with A?. We followed the amyloid fibril formation of A?40 and A?42 using thioflavin T fluorescence in the presence of six charge variants of calbindin D9k and single-chain monellin. The formation of fibrils was verified with transmission electron microscopy. We observe retardation of the aggregation process from proteins with net charge +8, +2, -2, and -4, whereas no effect is observed for proteins with net charge of -6 and -8. The single-chain monellin mutant with the highest net charge, scMN+8, has the largest retarding effect on the amyloid fibril formation process, which is noticeably delayed at as low as a 0.01:1 scMN+8 to A?40 molar ratio. scMN+8 is also the mutant with the fastest association to A?40 as detected by surface plasmon resonance, although all retarding variants of calbindin D9k and single-chain monellin bind to A?40. PMID:24475785

Assarsson, Anna; Hellstrand, Erik; Cabaleiro-Lago, Celia; Linse, Sara

2014-04-16

13

Conformational-Dependent and Independent RNA Binding to the Fragile X Mental Retardation Protein  

PubMed Central

The interaction between the fragile X mental retardation protein (FMRP) and BC1 RNA has been the subject of controversy. We probed the parameters of RNA binding to FMRP in several ways. Nondenaturing agarose gel analysis showed that BC1 RNA transcripts produced by in vitro transcription contain a population of conformers, which can be modulated by preannealing. Accordingly, FMRP differentially binds to the annealed and unannealed conformer populations. Using partial RNase digestion, we demonstrate that annealed BC1 RNA contains a unique conformer that FMRP likely binds. We further demonstrate that this interaction is 100-fold weaker than that the binding of eEF-1A mRNA and FMRP, and that preannealing is not a general requirement for FMRP's interaction with RNA. In addition, binding does not require the N-terminal 204 amino acids of FMRP, methylated arginine residues and can be recapitulated by both fragile X paralogs. Altogether, our data continue to support a model in which BC1 RNA functions independently of FMRP. PMID:21772992

Yan, Xin; Denman, Robert B.

2011-01-01

14

Cell morphogenesis of Trypanosoma brucei requires the paralogous, differentially expressed calpain-related proteins CAP5.5 and CAP5.5V.  

PubMed

Proteins from the calpain super-family are involved in developmentally- and environmentally-regulated re-modelling of the eukaryotic cytoskeleton and the dynamic organisation of signal transduction cascades. In trypanosomatid parasites, calpain-related gene families are unusually large, but we have little insight into the functional roles played by these molecules during trypanosomatid lifecycles. Here we report that CAP5.5, a cytoskeletal calpain-related protein subject to strict stage-specific expression in the sleeping sickness parasite Trypanosoma brucei, is essential and required for correct cell morphogenesis of procyclic (tsetse mid-gut stage) T. brucei. Striking consequences of CAP5.5 RNA interference are the loss of protein from the posterior cell-end, organelle mis-positioning giving rise to aberrant cytokinesis, and disorganisation of the sub-pellicular microtubules that define trypanosome cell shape. We further report that the stage-specificity of CAP5.5 expression can be explained by the presence of a paralogue, CAP5.5V, which is required for cell morphogenesis in bloodstream T. brucei; RNAi against this paralogous protein results in a qualitatively similar phenotype to that described for procyclic CAP5.5 RNAi mutants. By comparison to recently described phenotypes for other procyclic trypanosome RNAi mutants, likely functions for CAP5.5 and CAP5.5V are discussed. PMID:19656721

Olego-Fernandez, Sofia; Vaughan, Sue; Shaw, Michael K; Gull, Keith; Ginger, Michael L

2009-11-01

15

Elucidating the evolutionary history and expression patterns of nucleoside phosphorylase paralogs (vegetative storage proteins) in Populus and the plant kingdom  

PubMed Central

Background Nucleoside phosphorylases (NPs) have been extensively investigated in human and bacterial systems for their role in metabolic nucleotide salvaging and links to oncogenesis. In plants, NP-like proteins have not been comprehensively studied, likely because there is no evidence of a metabolic function in nucleoside salvage. However, in the forest trees genus Populus a family of NP-like proteins function as an important ecophysiological adaptation for inter- and intra-seasonal nitrogen storage and cycling. Results We conducted phylogenetic analyses to determine the distribution and evolution of NP-like proteins in plants. These analyses revealed two major clusters of NP-like proteins in plants. Group I proteins were encoded by genes across a wide range of plant taxa while proteins encoded by Group II genes were dominated by species belonging to the order Malpighiales and included the Populus Bark Storage Protein (BSP) and WIN4-like proteins. Additionally, we evaluated the NP-like genes in Populus by examining the transcript abundance of the 13 NP-like genes found in the Populus genome in various tissues of plants exposed to long-day (LD) and short-day (SD) photoperiods. We found that all 13 of the Populus NP-like genes belonging to either Group I or II are expressed in various tissues in both LD and SD conditions. Tests of natural selection and expression evolution analysis of the Populus genes suggests that divergence in gene expression may have occurred recently during the evolution of Populus, which supports the adaptive maintenance models. Lastly, in silico analysis of cis-regulatory elements in the promoters of the 13 NP-like genes in Populus revealed common regulatory elements known to be involved in light regulation, stress/pathogenesis and phytohormone responses. Conclusion In Populus, the evolution of the NP-like protein and gene family has been shaped by duplication events and natural selection. Expression data suggest that previously uncharacterized NP-like proteins may function in nutrient sensing and/or signaling. These proteins are members of Group I NP-like proteins, which are widely distributed in many plant taxa. We conclude that NP-like proteins may function in plants, although this function is undefined. PMID:23957885

2013-01-01

16

Orthology and paralogy constraints: satisfiability and consistency  

PubMed Central

Background A variety of methods based on sequence similarity, reconciliation, synteny or functional characteristics, can be used to infer orthology and paralogy relations between genes of a given gene family  G. But is a given set  C of orthology/paralogy constraints possible, i.e., can they simultaneously co-exist in an evolutionary history for  G? While previous studies have focused on full sets of constraints, here we consider the general case where  C does not necessarily involve a constraint for each pair of genes. The problem is subdivided in two parts: (1) Is  C satisfiable, i.e. can we find an event-labeled gene tree G inducing  C? (2) Is there such a G which is consistent, i.e., such that all displayed triplet phylogenies are included in a species tree? Results Previous results on the Graph sandwich problem can be used to answer to (1), and we provide polynomial-time algorithms for satisfiability and consistency with a given species tree. We also describe a new polynomial-time algorithm for the case of consistency with an unknown species tree and full knowledge of pairwise orthology/paralogy relationships, as well as a branch-and-bound algorithm in the case when unknown relations are present. We show that our algorithms can be used in combination with ProteinOrtho, a sequence similarity-based orthology detection tool, to extract a set of robust orthology/paralogy relationships.

2014-01-01

17

Fragile X mental retardation protein and synaptic plasticity  

E-print Network

Loss of the translational repressor FMRP causes Fragile X syndrome. In healthy neurons, FMRP modulates the local translation of numerous synaptic proteins. Synthesis of these proteins is required for the maintenance and ...

Sidorov, Michael Samuel

18

Protein Implicated in Nonsyndromic Mental Retardation Regulates Protein Kinase A (PKA) Activity  

PubMed Central

Mutation of the coiled-coil and C2 domain-containing 1A (CC2D1A) gene, which encodes a C2 domain and DM14 domain-containing protein, has been linked to severe autosomal recessive nonsyndromic mental retardation. Using a mouse model that produces a truncated form of CC2D1A that lacks the C2 domain and three of the four DM14 domains, we show that CC2D1A is important for neuronal differentiation and brain development. CC2D1A mutant neurons are hypersensitive to stress and have a reduced capacity to form dendrites and synapses in culture. At the biochemical level, CC2D1A transduces signals to the cyclic adenosine 3?,5?-monophosphate (cAMP)-protein kinase A (PKA) pathway during neuronal cell differentiation. PKA activity is compromised, and the translocation of its catalytic subunit to the nucleus is also defective in CC2D1A mutant cells. Consistently, phosphorylation of the PKA target cAMP-responsive element-binding protein, at serine 133, is nearly abolished in CC2D1A mutant cells. The defects in cAMP/PKA signaling were observed in fibroblast, macrophage, and neuronal primary cells derived from the CC2D1A KO mice. CC2D1A associates with the cAMP-PKA complex following forskolin treatment and accumulates in vesicles or on the plasma membrane in wild-type cells, suggesting that CC2D1A may recruit the PKA complex to the membrane to facilitate signal transduction. Together, our data show that CC2D1A is an important regulator of the cAMP/PKA signaling pathway, which may be the underlying cause for impaired mental function in nonsyndromic mental retardation patients with CC2D1A mutation. PMID:22375002

Al-Tawashi, Azza; Jung, Sung Yun; Liu, Dou; Su, Bing; Qin, Jun

2012-01-01

19

Evolutionary constraints on structural similarity in orthologs and paralogs  

PubMed Central

Although a quantitative relationship between sequence similarity and structural similarity has long been established, little is known about the impact of orthology on the relationship between protein sequence and structure. Among homologs, orthologs (derived by speciation) more frequently have similar functions than paralogs (derived by duplication). Here, we hypothesize that an orthologous pair will tend to exhibit greater structural similarity than a paralogous pair at the same level of sequence similarity. To test this hypothesis, we used 284,459 pairwise structure-based alignments of 12,634 unique domains from SCOP as well as orthology and paralogy assignments from OrthoMCL DB. We divided the comparisons by sequence identity and determined whether the sequence-structure relationship differed between the orthologs and paralogs. We found that at levels of sequence identity between 30 and 70%, orthologous domain pairs indeed tend to be significantly more structurally similar than paralogous pairs at the same level of sequence identity. An even larger difference is found when comparing ligand binding residues instead of whole domains. These differences between orthologs and paralogs are expected to be useful for selecting template structures in comparative modeling and target proteins in structural genomics. PMID:19472362

Peterson, Mark E; Chen, Feng; Saven, Jeffery G; Roos, David S; Babbitt, Patricia C; Sali, Andrej

2009-01-01

20

Fragile X mental retardation protein and synaptic plasticity  

PubMed Central

Loss of the translational repressor FMRP causes Fragile X syndrome. In healthy neurons, FMRP modulates the local translation of numerous synaptic proteins. Synthesis of these proteins is required for the maintenance and regulation of long-lasting changes in synaptic strength. In this role as a translational inhibitor, FMRP exerts profound effects on synaptic plasticity. PMID:23566911

2013-01-01

21

Deletion of PTEN Produces Deficits in Conditioned Fear and Increases Fragile X Mental Retardation Protein  

ERIC Educational Resources Information Center

The phosphatase and tensin homolog detected on chromosome 10 (PTEN) gene product modulates activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway. The PI3K pathway has been found to be involved in the regulation of the fragile X mental retardation protein, which is important for long-term depression and in the formation of new…

Lugo, Joaquin N.; Smith, Gregory D.; Morrison, Jessica B.; White, Jessika

2013-01-01

22

The Fragile X Mental Retardation Protein, FMRP, Recognizes G-Quartets  

ERIC Educational Resources Information Center

Fragile X mental retardation is a disease caused by the loss of function of a single RNA-binding protein, FMRP. Identifying the RNA targets recognized by FMRP is likely to reveal much about its functions in controlling some aspects of memory and behavior. Recent evidence suggests that one of the predominant RNA motifs recognized by the FMRP…

Darnell, Jennifer C.; Warren, Stephen T.; Darnell, Robert B.

2004-01-01

23

Fragile Mental Retardation Protein Interacts with the RNA-Binding Protein Caprin1 in Neuronal RiboNucleoProtein Complexes  

PubMed Central

Fragile X syndrome is caused by the absence of the Fragile X Mental Retardation Protein (FMRP), an RNA-binding protein. FMRP is associated with messenger RiboNucleoParticles (mRNPs) present in polyribosomes and its absence in neurons leads to alteration in synaptic plasticity as a result of translation regulation defects. The molecular mechanisms by which FMRP plays a role in translation regulation remain elusive. Using immunoprecipitation approaches with monoclonal Ab7G1-1 and a new generation of chicken antibodies, we identified Caprin1 as a novel FMRP-cellular partner. In vivo and in vitro evidence show that Caprin1 interacts with FMRP at the level of the translation machinery as well as in trafficking neuronal granules. As an RNA-binding protein, Caprin1 has in common with FMRP at least two RNA targets that have been identified as CaMKII? and Map1b mRNAs. In view of the new concept that FMRP species bind to RNA regardless of known structural motifs, we propose that protein interactors might modulate FMRP functions. PMID:22737234

El Fatimy, Rachid; Tremblay, Sandra; Dury, Alain Y.; Solomon, Samuel; De Koninck, Paul; Schrader, John W.; Khandjian, Edouard W.

2012-01-01

24

The fragile X mental retardation protein inhibits translation via interacting with mRNA  

PubMed Central

Fragile X syndrome is a frequent form of inherited mental retardation caused by functional loss of the fragile X mental retardation protein, FMRP. The function of FMRP is unknown, as is the mechanism by which its loss leads to cognitive deficits. Recent studies have determined that FMRP is a selective RNA-binding protein associated with polyribosomes, leading to the hypothesis that FMRP may be involved in translational regulation. Here we show that purified recombinant FMRP causes a dose-dependent translational inhibition of brain poly(A) RNA in rabbit reticulocyte lysate without accelerated mRNA degradation. In our translation reaction FMRP interacts with other messenger ribonucleoproteins and pre-exposure of FMRP to mRNA significantly increased the potency of FMRP as a translation inhibitor. Translation suppression by FMRP is reversed in a trans-acting manner by the 3?-untranslated portion of the Fmr1 message, which binds FMRP, suggesting that FMRP inhibits translation via interacting with mRNA. Consistently FMRP suppresses translation of the parathyroid hormone transcript, which binds FMRP, but not the ?-globin transcript, which does not bind FMRP. Moreover, removing the FMRP-binding site on a translation template abolishes the inhibitory effect of FMRP. Taken together, our results support the hypothesis that FMRP inhibits translation via interactions with the translation template. PMID:11376146

Li, Zhenzhong; Zhang, Youyi; Ku, Li; Wilkinson, Keith D.; Warren, Stephen T.; Feng, Yue

2001-01-01

25

Distribution of fragile X mental retardation protein in the human auditory brainstem.  

PubMed

Fragile X mental retardation protein (FMRP) binds select mRNAs, functions in intracellular transport of these mRNAs and represses their translation. FMRP is highly expressed in neurons and lack of FMRP has been shown to result in dendritic dysmorphology and altered synaptic function. FMRP is known to interact with mRNAs for the Kv3.1b potassium channel which is required for neurons to fire action potentials at high rates with remarkable temporal precision. Auditory brainstem neurons are known for remarkably high spike rates and expression of Kv3.1b potassium channels. Fragile X syndrome (FXS) is a genetic disorder caused by a mutation in the fragile X mental retardation 1 gene (Fmr1) resulting in decreased expression of FMRP and subsequent intellectual disability, seizures, attention deficit and hypersensitivity to auditory and other sensory stimuli. We therefore hypothesize that the auditory difficulties in FXS result, at least in part, from dysfunction of auditory brainstem neurons. To examine this hypothesis, we have studied normal human brainstem tissue with immunohistochemical techniques and confocal microscopy. Our results demonstrate that FMRP is widely expressed in cell bodies and dendritic arbors of neurons in the human cochlear nucleus and superior olivary complex and also that coincidence detector neurons of the medial superior olive colocalization of FMRP and Kv3.1b. We interpret these observations to suggest that the lower auditory brainstem is a potential site of dysfunction in FXS. PMID:24838064

Beebe, K; Wang, Y; Kulesza, R

2014-07-25

26

On BC1 RNA and the fragile X mental retardation protein.  

PubMed

The fragile X mental retardation protein (FMRP), the functional absence of which causes fragile X syndrome, is an RNA-binding protein that has been implicated in the regulation of local protein synthesis at the synapse. The mechanism of FMRP's interaction with its target mRNAs, however, has remained controversial. In one model, it has been proposed that BC1 RNA, a small non-protein-coding RNA that localizes to synaptodendritic domains, operates as a requisite adaptor by specifically binding to both FMRP and, via direct base-pairing, to FMRP target mRNAs. Other models posit that FMRP interacts with its target mRNAs directly, i.e., in a BC1-independent manner. Here five laboratories independently set out to test the BC1-FMRP model. We report that specific BC1-FMRP interactions could be documented neither in vitro nor in vivo. Interactions between BC1 RNA and FMRP target mRNAs were determined to be of a nonspecific nature. Significantly, the association of FMRP with bona fide target mRNAs was independent of the presence of BC1 RNA in vivo. The combined experimental evidence is discordant with a proposed scenario in which BC1 RNA acts as a bridge between FMRP and its target mRNAs and rather supports a model in which BC1 RNA and FMRP are translational repressors that operate independently. PMID:18184799

Iacoangeli, Anna; Rozhdestvensky, Timofey S; Dolzhanskaya, Natalia; Tournier, Barthélémy; Schütt, Janin; Brosius, Jürgen; Denman, Robert B; Khandjian, Edouard W; Kindler, Stefan; Tiedge, Henri

2008-01-15

27

An archaeal RadA paralog influences presynaptic filament formation  

PubMed Central

Recombinases of the RecA family play vital roles in homologous recombination, a high-fidelity mechanism to repair DNA double-stranded breaks. These proteins catalyze strand invasion and exchange after forming dynamic nucleoprotein filaments on ssDNA. Increasing evidence suggests that stabilization of these dynamic filaments is a highly conserved function across diverse species. Here, we analyze the presynaptic filament formation and DNA binding characteristics of the Sulfolobus solfataricus recombinase SsoRadA in conjunction with the SsoRadA paralog SsoRal1. In addition to constraining SsoRadA ssDNA-dependent ATPase activity, the paralog also enhances SsoRadA ssDNA binding, effectively influencing activities necessary for presynaptic filament formation. These activities result in enhanced SsoRadA-mediated strand invasion in the presence of SsoRal1 and suggest a filament stabilization function for the SsoRal1 protein. PMID:23622866

Graham, William J.; Rolfsmeier, Michael L.; Haseltine, Cynthia A.

2014-01-01

28

Heat Shock Protein 70 Expression is Increased in the Liver of Neonatal Intrauterine Growth Retardation Piglets  

PubMed Central

Intrauterine growth retardation (IUGR) leads to the dysfunction in digestive system, as well as the alteration in the expression of some functional proteins. Heat shock protein 70 (Hsp70) could be induced by various stress factors, but whether Hsp70 expression is changed in neonatal IUGR infants has not been demonstrated. This study was conducted to explore the expression of Hsp70 in the liver by using the IUGR piglet model. Liver and plasma samples were obtained from IUGR and normal birth weight (NBW) piglets at birth. The neonatal IUGR piglets had significantly lower liver weight than their counterparts. The activities of aspartate aminotransferase and alanine aminotransferase in serum were enhanced significantly in IUGR indicating liver dysfunction. The activities of superoxide dismutase (p<0.01), glutathione peroxidase (p<0.01) and catalase (p>0.05) were lower and the level of malondialdehybe was higher (p<0.05) in IUGR liver compared with in NBW. According to the results of histological tests, fatty hepatic infiltrates and cytoplasmic vacuolization were present in the liver of IUGR piglets, but not in NBW liver. The expression of Hsp70 protein was significantly higher (p<0.05) in IUGR piglet liver than in NBW. Similar to where the hepatic injuries were observed, location of Hsp70 was mostly in the midzonal hepatic lobule indicating that oxidative stress might be responsible for the increased expression of Hsp70. PMID:25049668

Li, Wei; Zhong, Xiang; Zhang, Lili; Wang, Yuanxiao; Wang, Tian

2012-01-01

29

Nuclear Fragile X Mental Retardation Protein Is localized to Cajal Bodies  

PubMed Central

Fragile X syndrome is caused by loss of function of a single gene encoding the Fragile X Mental Retardation Protein (FMRP). This RNA-binding protein, widely expressed in mammalian tissues, is particularly abundant in neurons and is a component of messenger ribonucleoprotein (mRNP) complexes present within the translational apparatus. The absence of FMRP in neurons is believed to cause translation dysregulation and defects in mRNA transport essential for local protein synthesis and for synaptic development and maturation. A prevalent model posits that FMRP is a nucleocytoplasmic shuttling protein that transports its mRNA targets from the nucleus to the translation machinery. However, it is not known which of the multiple FMRP isoforms, resulting from the numerous alternatively spliced FMR1 transcripts variants, would be involved in such a process. Using a new generation of anti-FMRP antibodies and recombinant expression, we show here that the most commonly expressed human FMRP isoforms (ISO1 and 7) do not localize to the nucleus. Instead, specific FMRP isoforms 6 and 12 (ISO6 and 12), containing a novel C-terminal domain, were the only isoforms that localized to the nuclei in cultured human cells. These isoforms localized to specific p80-coilin and SMN positive structures that were identified as Cajal bodies. The Cajal body localization signal was confined to a 17 amino acid stretch in the C-terminus of human ISO6 and is lacking in a mouse Iso6 variant. As FMRP is an RNA-binding protein, its presence in Cajal bodies suggests additional functions in nuclear post-transcriptional RNA metabolism. Supporting this hypothesis, a missense mutation (I304N), known to alter the KH2-mediated RNA binding properties of FMRP, abolishes the localization of human FMRP ISO6 to Cajal bodies. These findings open unexplored avenues in search for new insights into the pathophysiology of Fragile X Syndrome. PMID:24204304

Tremblay, Sandra; Rose, Timothy M.; Cote, Jocelyn; De Koninck, Paul; Khandjian, Edouard W.

2013-01-01

30

Differential domain evolution and complex RNA processing in a family of paralogous EPB41 (protein 4.1) genes facilitates expression of diverse tissue-specific isoforms  

SciTech Connect

The EPB41 (protein 4.1) genes epitomize the resourcefulness of the mammalian genome to encode a complex proteome from a small number of genes. By utilizing alternative transcriptional promoters and tissue-specific alternative pre-mRNA splicing, EPB41, EPB41L2, EPB41L3, and EPB41L1 encode a diverse array of structural adapter proteins. Comparative genomic and transcript analysis of these 140kb-240kb genes indicates several unusual features: differential evolution of highly conserved exons encoding known functional domains, interspersed with unique exons whose size and sequence variations contribute substantially to intergenic diversity: alternative first exons, most of which map far upstream of the coding regions; and complex tissue-specific alternative pre-mRNA splicing that facilitates synthesis of functionally different complements of 4.1 proteins in various cells. Understanding the splicing regulatory networks that control protein 4.1 expression will be critical to a full appreciation of the many roles of 4.1 proteins in normal cell biology and their proposed roles in human cancer.

Parra, Marilyn; Gee, Sherry; Chan, Nadine; Ryaboy, Dmitriy; Dubchak, Inna; Narla, Mohandas; Gascard, Philippe D.; Conboy, John G.

2004-07-15

31

Automatic clustering of orthologs and in-paralogs from pairwise species comparisons.  

PubMed

Orthologs are genes in different species that originate from a single gene in the last common ancestor of these species. Such genes have often retained identical biological roles in the present-day organisms. It is hence important to identify orthologs for transferring functional information between genes in different organisms with a high degree of reliability. For example, orthologs of human proteins are often functionally characterized in model organisms. Unfortunately, orthology analysis between human and e.g. invertebrates is often complex because of large numbers of paralogs within protein families. Paralogs that predate the species split, which we call out-paralogs, can easily be confused with true orthologs. Paralogs that arose after the species split, which we call in-paralogs, however, are bona fide orthologs by definition. Orthologs and in-paralogs are typically detected with phylogenetic methods, but these are slow and difficult to automate. Automatic clustering methods based on two-way best genome-wide matches on the other hand, have so far not separated in-paralogs from out-paralogs effectively. We present a fully automatic method for finding orthologs and in-paralogs from two species. Ortholog clusters are seeded with a two-way best pairwise match, after which an algorithm for adding in-paralogs is applied. The method bypasses multiple alignments and phylogenetic trees, which can be slow and error-prone steps in classical ortholog detection. Still, it robustly detects complex orthologous relationships and assigns confidence values for both orthologs and in-paralogs. The program, called INPARANOID, was tested on all completely sequenced eukaryotic genomes. To assess the quality of INPARANOID results, ortholog clusters were generated from a dataset of worm and mammalian transmembrane proteins, and were compared to clusters derived by manual tree-based ortholog detection methods. This study led to the identification with a high degree of confidence of over a dozen novel worm-mammalian ortholog assignments that were previously undetected because of shortcomings of phylogenetic methods.A WWW server that allows searching for orthologs between human and several fully sequenced genomes is installed at http://www.cgb.ki.se/inparanoid/. This is the first comprehensive resource with orthologs of all fully sequenced eukaryotic genomes. Programs and tables of orthology assignments are available from the same location. PMID:11743721

Remm, M; Storm, C E; Sonnhammer, E L

2001-12-14

32

Fragile X mental retardation protein stimulates ribonucleoprotein assembly of influenza A virus  

NASA Astrophysics Data System (ADS)

The ribonucleoprotein (RNP) of the influenza A virus is responsible for the transcription and replication of viral RNA in the nucleus. These processes require interplay between host factors and RNP components. Here, we report that the Fragile X mental retardation protein (FMRP) targets influenza virus RNA synthesis machinery and facilitates virus replication both in cell culture and in mice. We demonstrate that FMRP transiently associates with viral RNP and stimulates viral RNP assembly through RNA-mediated interaction with the nucleoprotein. Furthermore, the KH2 domain of FMRP mediates its association with the nucleoprotein. A point mutation (I304N) in the KH2 domain, identified from a Fragile X syndrome patient, disrupts the FMRP-nucleoprotein association and abolishes the ability of FMRP to participate in viral RNP assembly. We conclude that FMRP is a critical host factor used by influenza viruses to facilitate viral RNP assembly. Our observation reveals a mechanism of influenza virus RNA synthesis and provides insights into FMRP functions.

Zhou, Zhuo; Cao, Mengmeng; Guo, Yang; Zhao, Lili; Wang, Jingfeng; Jia, Xue; Li, Jianguo; Wang, Conghui; Gabriel, Gülsah; Xue, Qinghua; Yi, Yonghong; Cui, Sheng; Jin, Qi; Wang, Jianwei; Deng, Tao

2014-02-01

33

Sequence variation of alcohol dehydrogenase (Adh) paralogs in cactophilic Drosophila.  

PubMed

This study focuses on the population genetics of alcohol dehydrogenase (Adh) in cactophilic Drosophila. Drosophila mojavensis and D. arizonae utilize cactus hosts, and each host contains a characteristic mixture of alcohol compounds. In these Drosophila species there are two functional Adh loci, an adult form (Adh-2) and a larval and ovarian form (Adh-1). Overall, the greater level of variation segregating in D. arizonae than in D. mojavensis suggests a larger population size for D. arizonae. There are markedly different patterns of variation between the paralogs across both species. A 16-bp intron haplotype segregates in both species at Adh-2, apparently the product of an ancient gene conversion event between the paralogs, which suggests that there is selection for the maintenance of the intron structure possibly for the maintenance of pre-mRNA structure. We observe a pattern of variation consistent with adaptive protein evolution in the D. mojavensis lineage at Adh-1, suggesting that the cactus host shift that occurred in the divergence of D. mojavensis from D. arizonae had an effect on the evolution of the larval expressed paralog. Contrary to previous work we estimate a recent time for both the divergence of D. mojavensis and D. arizonae (2.4 +/- 0.7 MY) and the age of the gene duplication (3.95 +/- 0.45 MY). PMID:12586706

Matzkin, Luciano M; Eanes, Walter F

2003-01-01

34

Fragile X mental retardation protein regulates trans-synaptic signaling in Drosophila.  

PubMed

Fragile X syndrome (FXS), the most common inherited determinant of intellectual disability and autism spectrum disorders, is caused by loss of the fragile X mental retardation 1 (FMR1) gene product (FMRP), an mRNA-binding translational repressor. A number of conserved FMRP targets have been identified in the well-characterized Drosophila FXS disease model, but FMRP is highly pleiotropic in function and the full spectrum of FMRP targets has yet to be revealed. In this study, screens for upregulated neural proteins in Drosophila fmr1 (dfmr1) null mutants reveal strong elevation of two synaptic heparan sulfate proteoglycans (HSPGs): GPI-anchored glypican Dally-like protein (Dlp) and transmembrane Syndecan (Sdc). Our recent work has shown that Dlp and Sdc act as co-receptors regulating extracellular ligands upstream of intracellular signal transduction in multiple trans-synaptic pathways that drive synaptogenesis. Consistently, dfmr1 null synapses exhibit altered WNT signaling, with changes in both Wingless (Wg) ligand abundance and downstream Frizzled-2 (Fz2) receptor C-terminal nuclear import. Similarly, a parallel anterograde signaling ligand, Jelly belly (Jeb), and downstream ERK phosphorylation (dpERK) are depressed at dfmr1 null synapses. In contrast, the retrograde BMP ligand Glass bottom boat (Gbb) and downstream signaling via phosphorylation of the transcription factor MAD (pMAD) seem not to be affected. To determine whether HSPG upregulation is causative for synaptogenic defects, HSPGs were genetically reduced to control levels in the dfmr1 null background. HSPG correction restored both (1) Wg and Jeb trans-synaptic signaling, and (2) synaptic architecture and transmission strength back to wild-type levels. Taken together, these data suggest that FMRP negatively regulates HSPG co-receptors controlling trans-synaptic signaling during synaptogenesis, and that loss of this regulation causes synaptic structure and function defects characterizing the FXS disease state. PMID:24046358

Friedman, Samuel H; Dani, Neil; Rushton, Emma; Broadie, Kendal

2013-11-01

35

Molecular mechanisms of paralogous compensation and the robustness of cellular networks.  

PubMed

Robustness is the ability of a system to maintain its function despite environmental or genetic perturbation. Genetic robustness is a key emerging property of living systems and is achieved notably by the presence of partially redundant parts that result from gene duplication. Functional overlap between paralogs allows them to compensate for each other's loss, as commonly revealed by aggravating genetic interactions. However, the molecular mechanisms linking the genotype (loss of function of a gene) to the phenotype (genetic buffering by a paralog) are still poorly understood and the molecular aspects of this compensation are rarely addressed in studies of gene duplicates. Here, we review molecular mechanisms of functional compensation between paralogous genes, many of which from studies that were not meant to study this phenomenon. We propose a standardized terminology and, depending on whether or not the molecular behavior of the intact gene is modified in response to the deletion of its paralog, we classify mechanisms of compensation into passive and active events. We further describe three non-exclusive mechanisms of active paralogous compensation for which there is evidence in the literature: changes in abundance, in localization, and in protein interactions. This review will serve as a framework for the genetic and molecular analysis of paralogous compensation, one of the universal features of genetic systems. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 488-499, 2013. © 2013 Wiley Periodicals, Inc. PMID:24376223

Diss, Guillaume; Ascencio, Diana; DeLuna, Alexander; Landry, Christian R

2014-11-01

36

The nuclear microspherule protein 58 is a novel RNA-binding protein that interacts with fragile X mental retardation protein in polyribosomal mRNPs from neurons.  

PubMed

The fragile X syndrome, the leading cause of inherited mental retardation, is due to the inactivation of the fragile mental retardation 1 gene (FMR1) and the subsequent absence of its gene product FMRP. This RNA-binding protein is thought to control mRNA translation and its absence in fragile X cells leads to alteration in protein synthesis. In neurons, FMRP is thought to repress specific mRNAs during their transport as silent ribonucleoparticles (mRNPs) from the cell body to the distant synapses which are the sites of local synthesis of neuro-specific proteins. The mechanism by which FMRP sorts out its different mRNAs targets might be tuned by the intervention of different proteins. Using a yeast two-hybrid system, we identified MicroSpherule Protein 58 (MSP58) as a novel FMRP-cellular partner. In cell cultures, we found that MSP58 is predominantly present in the nucleus where it interacts with the nuclear isoform of FMRP. However, in neurons but not in glial cells, MSP58 is also present in the cytoplasmic compartment, as well as in neurites, where it co-localizes with FMRP. Biochemical evidence is given that MSP58 is associated with polyribosomal poly(A)+ mRNPs. We also show that MSP58, similar to FMRP, is present on polyribosomes prepared from synaptoneurosomes and that it behaves as an RNA-binding protein with a high affinity to the G-quartet structure. We propose that this novel cellular partner for FMRP escorts FMRP-containing mRNP from the nucleus and nucleolus to the somato-dendritic compartment where it might participate in neuronal translation regulation. PMID:16571602

Davidovic, Laetitia; Bechara, Elias; Gravel, Maud; Jaglin, Xavier H; Tremblay, Sandra; Sik, Attila; Bardoni, Barbara; Khandjian, Edouard W

2006-05-01

37

Characterization of paralogous protein families in rice  

E-print Network

Background: High gene numbers in plant genomes reflect polyploidy and major gene duplication events. Oryza sativa, cultivated rice, is a diploid monocotyledonous species with a ~390 Mb genome that has undergone segmental ...

Lin, Haining

38

Characterization of paralogous protein families in rice  

Microsoft Academic Search

BACKGROUND: High gene numbers in plant genomes reflect polyploidy and major gene duplication events. Oryza sativa, cultivated rice, is a diploid monocotyledonous species with a ~390 Mb genome that has undergone segmental duplication of a substantial portion of its genome. This, coupled with other genetic events such as tandem duplications, has resulted in a substantial number of its genes, and

Haining Lin; Shu Ouyang; Amy Egan; Kan Nobuta; Brian J Haas; Wei Zhu; Xun Gu; Joana C Silva; Blake C Meyers; C Robin Buell

2008-01-01

39

Distribution and Paralog Specificity of Mammalian DeSUMOylating Enzymes  

PubMed Central

SYNOPSIS The covalent attachment of the small ubiquitin-like protein modifier (SUMO) to target proteins results in modifications in their activity, binding interactions, localization or half-life. The reversal of this modification is catalyzed by SUMO-specific processing proteases (SENPs). Mammals contain four SUMO paralogs and six SENP enzymes. Our studies describe a systematic analysis of human SENPs, integrating estimates of relative selectivity for SUMO1 and SUMO2, and kinetic measurements of recombinant C-terminal SENP catalytic domains (cSENPs). We first characterized the reaction of each endogenous SENP and their catalytic domains (cSENP) with HA-tagged SUMO1 and SUMO2 vinyl sulfones (HA-SUMO-VS), active site-directed irreversible inhibitors of SENPs. We found that all cSENPs and endogenous SENP1 react with both SUMO paralogs, while all other endogeneous SENPs in mammalian cells and tissues display high selectivity for SUMO2-VS. To obtain more quantitative data, the kinetic properties of purified cSENPs were determined using SUMO1 or SUMO2-amidomethyl coumarin (SUMO-AMC) as substrate. All enzymes bind their respective substrates with high affinity. cSENP1 and cSENP2 process either SUMO substrate with similar affinity and catalytic efficiency; cSENP5 and cSENP6 show marked catalytic specificity for SUMO2 as measured by KM and kcat while cSENP7 works only on SUMO2. Compared to cSENPs, recombinant full-length SENP1 and SENP2 show differences in SUMO selectivity indicating that paralog specificity is influenced by the presence of the variable N-terminal domain of each SENP. Our data suggests that SUMO2 metabolism is more dynamic than that of SUMO1 since most SENPs display a marked preference for SUMO2. PMID:20590526

Kolli, Nagamalleswari; Mikolajczyk, Jowita; Drag, Marcin; Mukhopadhyay, Debaditya; Moffatt, Nela; Dasso, Mary; Salvesen, Guy; Wilkinson, Keith D.

2013-01-01

40

OPTIC: orthologous and paralogous transcripts in clades  

Microsoft Academic Search

The genome sequences of a large number of metazoan species are now known. As multiple closely related genomes are sequenced, compara- tive studies that previously focussed on only pairs of genomes can now be extended over whole clades. The orthologous and paralogous transcripts in clades (OPTIC) database currently provides sets of gene predictions and orthology assignments for three clades: (i)

Andreas Heger; Chris P. Ponting

2008-01-01

41

Functional diversification of vitamin d receptor paralogs in teleost fish after a whole genome duplication event.  

PubMed

The diversity and success of teleost fishes (Actinopterygii) has been attributed to three successive rounds of whole-genome duplication (WGD). WGDs provide a source of raw genetic material for evolutionary forces to act upon, resulting in the divergence of genes with altered or novel functions. The retention of multiple gene pairs (paralogs) in teleosts provides a unique opportunity to study how genes diversify and evolve after a WGD. This study examines the hypothesis that vitamin D receptor (VDR) paralogs (VDR? and VDR?) from two distantly related teleost orders have undergone functional divergence subsequent to the teleost-specific WGD. VDR? and VDR? paralogs were cloned from the Japanese medaka (Beloniformes) and the zebrafish (Cypriniformes). Initial transactivation studies using 1?, 25-dihydroxyvitamin D3 revealed that although VDR? and VDR? maintain similar ligand potency, the maximum efficacy of VDR? was significantly attenuated compared with VDR? in both species. Subsequent analyses revealed that VDR? and VDR? maintain highly similar ligand affinities; however, VDR? demonstrated preferential DNA binding compared with VDR?. Protein-protein interactions between the VDR paralogs and essential nuclear receptor coactivators were investigated using transactivation and mammalian two-hybrid assays. Our results imply that functional differences between VDR? and VDR? occurred early in teleost evolution because they are conserved between distantly related species. Our results further suggest that the observed differences may be associated with differential protein-protein interactions between the VDR paralogs and coactivators. We speculate that the observed functional differences are due to subtle ligand-induced conformational differences between the two paralogs, leading to divergent downstream functions. PMID:25279795

Kollitz, Erin M; Hawkins, Mary Beth; Whitfield, G Kerr; Kullman, Seth W

2014-12-01

42

Transcriptomic and phenotypic analysis of paralogous spx gene function in Bacillus anthracis Sterne  

PubMed Central

Abstract Spx of Bacillus subtilis is a redox-sensitive protein, which, under disulfide stress, interacts with RNA polymerase to activate genes required for maintaining thiol homeostasis. Spx orthologs are highly conserved among low %GC Gram-positive bacteria, and often exist in multiple paralogous forms. In this study, we used B. anthracis Sterne, which harbors two paralogous spx genes, spxA1 and spxA2, to examine the phenotypes of spx null mutations and to identify the genes regulated by each Spx paralog. Cells devoid of spxA1 were sensitive to diamide and hydrogen peroxide, while the spxA1 spoxA2 double mutant was hypersensitive to the thiol-specific oxidant, diamide. Bacillus anthracis Sterne strains expressing spxA1DD or spxA2DD alleles encoding protease-resistant products were used in microarray and quantitative real-time polymerase chain reaction (RT-qPCR) analyses in order to uncover genes under SpxA1, SpxA2, or SpxA1/SpxA2 control. Comparison of transcriptomes identified many genes that were upregulated when either SpxA1DD or SpxA2DD was produced, but several genes were uncovered whose transcript levels increased in only one of the two SpxADD-expression strains, suggesting that each Spx paralog governs a unique regulon. Among genes that were upregulated were those encoding orthologs of proteins that are specifically involved in maintaining intracellular thiol homeostasis or alleviating oxidative stress. Some of these genes have important roles in B. anthracis pathogenesis, and a large number of upregulated hypothetical genes have no homology outside of the B. cereus/thuringiensis group. Microarray and RT-qPCR analyses also unveiled a regulatory link that exists between the two spx paralogous genes. The data indicate that spxA1 and spxA2 are transcriptional regulators involved in relieving disulfide stress but also control a set of genes whose products function in other cellular processes. Bacillus anthracis harbors two paralogs of the global transcriptional regulator of stress response, SpxA. SpxA1 and SpxA2 contribute to disulfide stress tolerance, but only SpxA1 functions in resistance to peroxide. Transcriptome analysis uncovered potential SpxA1 and SpxA2 regulon members, which include genes activated by both paralogs. However, paralog-specific gene activation was also observed. Genes encoding glutamate racemase, CoA disulfide reductase, and products functioning in bacillithiol biosynthesis, are among the genes activated by the SpxA paralogs. PMID:23873705

Barendt, Skye; Lee, Hyunwoo; Birch, Cierra; Nakano, Michiko M; Jones, Marcus; Zuber, Peter

2013-01-01

43

Identification of TGF-?, inhibin ?A and follistatin paralogs in the rainbow trout genome.  

PubMed

Since their initial discovery, TGF-? superfamily members have been considered multifunctional growth and differentiation factors in many cell types. Various studies have clearly demonstrated the key roles of specific TGF-? members in muscle growth, including myostatin and inhibin as well as genes, such as follistatin. By binding to TGF-? members, follistatin prevents TGF-? from binding to its receptors and thus neutralizes its activity. Here, we report the identification of the gene sequences of four TGF-? isoforms and three paralogs of TGF-?1, which we called TGF-?1a, TGF-?1b and TGF-?1c, four sequences of inhibin ?A paralogs; and two sequences of follistatin paralogs from rainbow trout. A phylogenetic analysis clearly indicated the existence of four monophyletic clades, corresponding to TGF-?1, -?2, -?3 and -?6. Based on their sequence identity TGF-?1a and -?1c are grouped together, whereas TGF-?1b appears more divergent even though it is grouped within the TGF-?1 clade. Alignments and phylogenetic analyses showed that the protein sequences of TGF-?, inhibin ?A and follistatin are extremely well conserved (>90%) relative to each other; however, their regulation and expression patterns are different. TGF-?2 and -?3 showed the most abundant expression in muscle and were the main TGF-? members expressed in this tissue. Follistatin and inhibin ?A paralogs were expressed in all tissues examined but with different patterns. Our identification of multiple copies of TGF-?, inhibin ?A and follistatin with different expression patterns suggests non-redundant functions for these paralogs in rainbow trout. PMID:25149133

de Mello, Fernanda; Streit, Danilo Pedro; Sabin, Nathalie; Gabillard, Jean-Charles

2014-01-01

44

Orthologs, paralogs and genome comparisons  

NASA Technical Reports Server (NTRS)

During the past decade, ancient gene duplications were recognized as one of the main forces in the generation of diverse gene families and the creation of new functional capabilities. New tools developed to search data banks for homologous sequences, and an increased availability of reliable three-dimensional structural information led to the recognition that proteins with diverse functions can belong to the same superfamily. Analyses of the evolution of these superfamilies promises to provide insights into early evolution but are complicated by several important evolutionary processes. Horizontal transfer of genes can lead to a vertical spread of innovations among organisms, therefore finding a certain property in some descendants of an ancestor does not guarantee that it was present in that ancestor. Complete or partial gene conversion between duplicated genes can yield phylogenetic trees with several, apparently independent gene duplications, suggesting an often surprising parallelism in the evolution of independent lineages. Additionally, the breakup of domains within a protein and the fusion of domains into multifunctional proteins makes the delineation of superfamilies a task that remains difficult to automate.

Gogarten, J. P.; Olendzenski, L.

1999-01-01

45

Phylogenetic Reconstruction of Orthology, Paralogy, and Conserved Synteny for Dog and Human  

Microsoft Academic Search

Accurate predictions of orthology and paralogy relationships are necessary to infer human molecular function from experiments in model organisms. Previous genome-scale approaches to predicting these relationships have been limited by their use of protein similarity and their failure to take into account multiple splicing events and gene prediction errors. We have developed PhyOP, a new phylogenetic orthology prediction pipeline based

Leo Goodstadt; Chris P. Ponting

2006-01-01

46

BRCA2 is epistatic to the RAD51 paralogs in response to DNA damage  

PubMed Central

Homologous recombination plays an important role in the high-fidelity repair of DNA double-strand breaks. A central player in this process, RAD51, polymerizes onto single-stranded DNA and searches for homology in a duplex donor DNA molecule, usually the sister chromatid. Homologous recombination is a highly regulated event in mammalian cells: some proteins have direct enzymatic functions, others mediate or overcome rate-limiting steps in the process, and still others signal cell cycle arrest to allow repair to occur. While the human BRCA2 protein has a clear role in delivering and loading RAD51 onto single-stranded DNA generated after resection of the DNA break, the mechanistic functions of the RAD51 paralogs remain unclear. In this study, we sought to determine the genetic interactions between BRCA2 and the RAD51 paralogs during DNA DSB repair. We utilized siRNA-mediated knockdown of these proteins in human cells to assess their impact on the DNA damage response. The results indicate that loss of BRCA2 alone imparts a more severe phenotype than the loss of any individual RAD51 paralog and that BRCA2 is epistatic to each of the four paralogs tested. PMID:23384538

Jensen, Ryan B.; Ozes, Ali; Kim, Taeho; Estep, Allison; Kowalczykowski, Stephen C.

2013-01-01

47

Boronate Complex Formation with Dopa Containing Mussel Adhesive Protein Retards pH-Induced Oxidation and Enables Adhesion to Mica  

PubMed Central

The biochemistry of mussel adhesion has inspired the design of surface primers, adhesives, coatings and gels for technological applications. These mussel-inspired systems often focus on incorporating the amino acid 3,4-dihydroxyphenyl-L-alanine (Dopa) or a catecholic analog into a polymer. Unfortunately, effective use of Dopa is compromised by its susceptibility to auto-oxidation at neutral pH. Oxidation can lead to loss of adhesive function and undesired covalent cross-linking. Mussel foot protein 5 (Mfp-5), which contains ?30 mole % Dopa, is a superb adhesive under reducing conditions but becomes nonadhesive after pH-induced oxidation. Here we report that the bidentate complexation of borate by Dopa to form a catecholato-boronate can be exploited to retard oxidation. Although exposure of Mfp-5 to neutral pH typically oxidizes Dopa, resulting in a>95% decrease in adhesion, inclusion of borate retards oxidation at the same pH. Remarkably, this Dopa-boronate complex dissociates upon contact with mica to allow for a reversible Dopa-mediated adhesion. The borate protection strategy allows for Dopa redox stability and maintained adhesive function in an otherwise oxidizing environment. PMID:25303409

Israelachvili, Jacob N.; Chen, Yunfei; Waite, J. Herbert

2014-01-01

48

Fragile X mental retardation protein controls synaptic vesicle exocytosis by modulating N-type calcium channel density  

PubMed Central

Fragile X syndrome (FXS), the most common heritable form of mental retardation, is characterized by synaptic dysfunction. Synaptic transmission depends critically on presynaptic calcium entry via voltage-gated calcium (CaV) channels. Here we show that the functional expression of neuronal N-type CaV channels (CaV2.2) is regulated by fragile X mental retardation protein (FMRP). We find that FMRP knockdown in dorsal root ganglion neurons increases CaV channel density in somata and in presynaptic terminals. We then show that FMRP controls CaV2.2 surface expression by targeting the channels to the proteasome for degradation. The interaction between FMRP and CaV2.2 occurs between the carboxy-terminal domain of FMRP and domains of CaV2.2 known to interact with the neurotransmitter release machinery. Finally, we show that FMRP controls synaptic exocytosis via CaV2.2 channels. Our data indicate that FMRP is a potent regulator of presynaptic activity, and its loss is likely to contribute to synaptic dysfunction in FXS. PMID:24709664

Ferron, Laurent; Nieto-Rostro, Manuela; Cassidy, John S.; Dolphin, Annette C.

2014-01-01

49

Delayed Myelination in an Intrauterine Growth Retardation Model Is Mediated by Oxidative Stress Upregulating Bone Morphogenetic Protein 4  

PubMed Central

Intrauterine growth retardation (IUGR) is associated with neurological deficits including cerebral palsy and cognitive and behavioral disabilities. The pathogenesis involves oxidative stress that leads to periventricular white matter injury with a paucity of mature oligodendrocytes and hypomyelination. The molecular mechanisms underlying this damage remain poorly understood. We employed a rat model of IUGR created by bilateral ligation of the uterine artery at embryonic day 19 that results in fetal growth retardation and oxidative stress in the developing brain. The IUGR rat pups showed significant delays in oligodendrocyte differentiation and myelination that resolved by 8 weeks. Bone morphogenetic protein 4 (BMP4), which inhibits oligodendrocyte maturation, was elevated in IUGR brains at postnatal time points and returned to near normal by adulthood. Despite the apparent recovery, behavioral deficiencies were found in 8-week-old female animals, suggesting that the early transient myelination defects have permanent effects. In support of these in vivo data, oligodendrocyte precursor cells cultured from postnatal IUGR rats retained increased BMP4 expression and impaired differentiation that was reversed with the BMP inhibitor noggin. Oxidants in oligodendrocyte cultures increased BMP expression, which decreased differentiation; however, abrogating BMP signaling with noggin in vitro and in BMP-deficient mice prevented these effects. Together, these findings suggest that IUGR results in delayed myelination through the generation of oxidative stress that leads to BMP4 upregulation. PMID:22710965

Reid, Mary V.; Murray, Kaitlin A.; Marsh, Eric D.; Golden, Jeffrey A.; Simmons, Rebecca A.; Grinspan, Judith B.

2012-01-01

50

Mental Retardation.  

ERIC Educational Resources Information Center

Thirteen papers by different authors consider the application of research findings and theoretical formulations to the practical appraisal and treatment of mental retardation. All suggest methods for shaping appropriate and adaptive behaviors in retarded individuals. The papers include "Definition, Diagnosis, and Classification" by D.W. Brison,…

Baumeister, Alfred A., Ed.

51

Learning and Behavioral Deficits Associated with the Absence of the Fragile X Mental Retardation Protein: What a Fly and Mouse Model Can Teach Us  

ERIC Educational Resources Information Center

The Fragile X syndrome (FXS) is the most frequent form of inherited mental disability and is considered a monogenic cause of autism spectrum disorder. FXS is caused by a triplet expansion that inhibits the expression of the "FMR1" gene. The gene product, the Fragile X Mental Retardation Protein (FMRP), regulates mRNA metabolism in brain…

Santos, Ana Rita; Kanellopoulos, Alexandros K.; Bagni, Claudia

2014-01-01

52

Brominated flame retardants, tetrabromobisphenol A and hexabromocyclododecane, activate mitogen-activated protein kinases (MAPKs) in human natural killer cells.  

PubMed

Natural killer (NK) cells provide a vital surveillance against virally infected cells, tumor cells, and antibody-coated cells through the release of cytolytic mediators and gamma interferon (IFN-?). Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded (EPS) and extruded (XPS) polystyrene foams for thermal insulation in the building and construction industry. Tetrabromobisphenol A (TBBPA) is used both as a reactive and an additive flame retardant in a variety of materials. HBCD and TBBPA contaminate the environment and are found in human blood samples. In previous studies, we have shown that other environmental contaminants, such as the dibutyltin (DBT) and tributyltin (TBT), decrease NK lytic function by activating mitogen-activated protein kinases (MAPKs) in the NK cells. HBCD and TBBPA also interfere with NK cell(s) lytic function. The current study evaluates whether HBCD and/or TBBPA have the capacity to activate MAPKs and MAPK kinases (MAP2Ks). The effects of concentrations of HBCD and TBBPA that inhibited lytic function on the phosphorylation state and total levels of the MAPKs (p44/42, p38, and JNK) and the phosphorylation and total levels of the MAP2Ks (MEK1/2 and MKK3/6) were examined. Results indicate that exposure of human NK cells to 10-0.5 ?M HBCD or TBBPA activate MAPKs and MAP2Ks. This HBCD and TBBPA-induced activation of MAPKs may leave them unavailable for activation by virally infected or tumor target cells and thus contributes to the observed decreases in lytic function seen in NK cells exposed to HBCD and TBBPA. PMID:25341744

Cato, Anita; Celada, Lindsay; Kibakaya, Esther Caroline; Simmons, Nadia; Whalen, Margaret M

2014-12-01

53

Mutations in mitochondrial ribosomal protein MRPL12 leads to growth retardation, neurological deterioration and mitochondrial translation deficiency?  

PubMed Central

Multiple respiratory chain deficiencies represent a common cause of mitochondrial diseases and are associated with a wide range of clinical symptoms. We report a subject, born to consanguineous parents, with growth retardation and neurological deterioration. Multiple respiratory chain deficiency was found in muscle and fibroblasts of the subject as well as abnormal assembly of complexes I and IV. A microsatellite genotyping of the family members detected only one region of homozygosity on chromosome 17q24.2–q25.3 in which we focused our attention to genes involved in mitochondrial translation. We sequenced MRPL12, encoding the mitochondrial ribosomal protein L12 and identified a c.542C>T transition in exon 5 changing a highly conserved alanine into a valine (p.Ala181Val). This mutation resulted in a decreased steady-state level of MRPL12 protein, with altered integration into the large ribosomal subunit. Moreover, an overall mitochondrial translation defect was observed in the subject's fibroblasts with a significant reduction of synthesis of COXI, COXII and COXIII subunits. Modeling of MRPL12 shows Ala181 positioned in a helix potentially involved in an interface of interaction suggesting that the p.Ala181Val change might be predicted to alter interactions with the elongation factors. These results contrast with the eubacterial orthologues of human MRPL12, where L7/L12 proteins do not appear to have a selective effect on translation. Therefore, analysis of the mutated version found in the subject presented here suggests that the mammalian protein does not function in an entirely analogous manner to the eubacterial L7/L12 equivalent. PMID:23603806

Serre, Valerie; Rozanska, Agata; Beinat, Marine; Chretien, Dominique; Boddaert, Nathalie; Munnich, Arnold; Rotig, Agnes; Chrzanowska-Lightowlers, Zofia M.

2013-01-01

54

ER stress-induced protein, VIGG, disturbs plant cation homeostasis, which is correlated with growth retardation and robustness to ER stress  

SciTech Connect

Highlights: {yields} VIGG is an ER stress-induced protein in plant. {yields} We examine the characteristics of VIGG-overexpressing Arabidopsis plants. {yields} VIGG-overexpressing plants reveal growth retardation and robustness to ER stress. {yields} VIGG disturbs cation homeostasis in plant. -- Abstract: VIGG is a putative endoplasmic reticulum (ER) resident protein induced by virus infection and ER stress, and is correlated with fruit quality in grapevine. The present study was undertaken to determine the biological function of VIGG in grapevine. Experiments using fluorescent protein-VIGG fusion protein demonstrated that VIGG is localized in ER and the ER targeting sequence is in the N-terminus. The overexpression of VIGG in Arabidopsis plant led to growth retardation. The rosette leaves of VIGG-overexpressing plants were smaller than those of the control plants and rolled at 42 days after seeding. VIGG-overexpressing plants revealed robustness to ER stress as well as the low expression of ER stress marker proteins, such as the luminal binding proteins. These characteristics of VIGG-overexpressing plants were supported by a microarray experiment that demonstrated the disruption of genes related to ER stress response and flowering, as well as cation mobility, in the plants. Finally, cation homeostasis in the plants was disturbed by the overexpression of VIGG. Taken together, these results suggest that VIGG may disturb cation homeostasis in plant, which is correlated with the robustness to ER stress and growth retardation.

Katoh, Hironori; Fujita, Keiko; Takuhara, Yuki [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan)] [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan); Ogawa, Atsushi [Department of Biological Production, Akita Prefectural University, Shimosinjyou-nakano 241-438, Akita 010-0195 (Japan)] [Department of Biological Production, Akita Prefectural University, Shimosinjyou-nakano 241-438, Akita 010-0195 (Japan); Suzuki, Shunji, E-mail: suzukis@yamanashi.ac.jp [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan)] [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan)

2011-02-18

55

A highly conserved protein family interacting with the fragile X mental retardation protein (FMRP) and displaying selective interactions with FMRP-related proteins FXR1P and FXR2P  

PubMed Central

The absence of the fragile X mental retardation protein (FMRP), encoded by the FMR1 gene, is responsible for pathologic manifestations in the Fragile X Syndrome, the most frequent cause of inherited mental retardation. FMRP is an RNA-binding protein associated with polysomes as part of a messenger ribonucleoprotein (mRNP) complex. Although its function is poorly understood, various observations suggest a role in local protein translation at neuronal dendrites and in dendritic spine maturation. We present here the identification of CYFIP1/2 (Cytoplasmic FMRP Interacting Proteins) as FMRP interactors. CYFIP1/2 share 88% amino acid sequence identity and represent the two members in humans of a highly conserved protein family. Remarkably, whereas CYFIP2 also interacts with the FMRP-related proteins FXR1P/2P, CYFIP1 interacts exclusively with FMRP. FMRP–CYFIP interaction involves the domain of FMRP also mediating homo- and heteromerization, thus suggesting a competition between interaction among the FXR proteins and interaction with CYFIP. CYFIP1/2 are proteins of unknown function, but CYFIP1 has recently been shown to interact with the small GTPase Rac1, which is implicated in development and maintenance of neuronal structures. Consistent with FMRP and Rac1 localization in dendritic fine structures, CYFIP1/2 are present in synaptosomal extracts. PMID:11438699

Schenck, Annette; Bardoni, Barbara; Moro, Annamaria; Bagni, Claudia; Mandel, Jean-Louis

2001-01-01

56

Dysregulation of fragile × mental retardation protein and metabotropic glutamate receptor 5 in superior frontal cortex of individuals with autism: a postmortem brain study  

Microsoft Academic Search

Background  Fragile × syndrome is caused by loss of function of the fragile × mental retardation 1 (FMR1) gene and shares multiple phenotypes with autism. We have previously found reduced expression of the protein product of FMR1 (FMRP) in vermis of adults with autism.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  In the current study, we have investigated levels of FMRP in the superior frontal cortex of people

S Hossein Fatemi; Timothy D Folsom

2011-01-01

57

Fragile X mental retardation protein is required for programmed cell death and clearance of developmentally-transient peptidergic neurons.  

PubMed

Fragile X syndrome (FXS), caused by loss of fragile X mental retardation 1 (FMR1) gene function, is the most common heritable cause of intellectual disability and autism spectrum disorders. The FMR1 product (FMRP) is an RNA-binding protein best established to function in activity-dependent modulation of synaptic connections. In the Drosophila FXS disease model, loss of functionally-conserved dFMRP causes synaptic overgrowth and overelaboration in pigment dispersing factor (PDF) peptidergic neurons in the adult brain. Here, we identify a very different component of PDF neuron misregulation in dfmr1 mutants: the aberrant retention of normally developmentally-transient PDF tritocerebral (PDF-TRI) neurons. In wild-type animals, PDF-TRI neurons in the central brain undergo programmed cell death and complete, processive clearance within days of eclosion. In the absence of dFMRP, a defective apoptotic program leads to constitutive maintenance of these peptidergic neurons. We tested whether this apoptotic defect is circuit-specific by examining crustacean cardioactive peptide (CCAP) and bursicon circuits, which are similarly developmentally-transient and normally eliminated immediately post-eclosion. In dfmr1 null mutants, CCAP/bursicon neurons also exhibit significantly delayed clearance dynamics, but are subsequently eliminated from the nervous system, in contrast to the fully persistent PDF-TRI neurons. Thus, the requirement of dFMRP for the retention of transitory peptidergic neurons shows evident circuit specificity. The novel defect of impaired apoptosis and aberrant neuron persistence in the Drosophila FXS model suggests an entirely new level of "pruning" dysfunction may contribute to the FXS disease state. PMID:21596027

Gatto, Cheryl L; Broadie, Kendal

2011-08-15

58

The paralogous SPX3 and SPX5 genes redundantly modulate Pi homeostasis in rice  

PubMed Central

The importance of SPX-domain-containing proteins to phosphate (Pi) homeostasis and signalling transduction has been established in plants. In this study, phylogenetic analysis revealed that OsSPX3 and OsSPX5 (SPX3/5) are paralogous SPX genes (SYG1/Pho81/XPR1) in cereal crops. SPX3/5 are specifically responsive to Pi starvation at both the transcriptional and post-transcriptional levels. Similar tissue expression patterns of the two genes and proteins were identified by in situ hybridization and the transgenic plants harbouring SPX3pro-SPX3-GUS or SPX5pro-SPX5-GUS fusions, respectively. Both SPX3/5 are localized in the nucleus and cytoplasm in rice protoplasts and plants. SPX3/5 negatively regulate root-to-shoot Pi translocation with redundant function. The data showed that the Pi-starvation-accumulated SPX3/5 proteins are players in restoring phosphate balance following phosphate starvation. In vitro and in vivo protein–protein interaction analyses indicated that these two proteins can form homodimers and heterodimers, also implying their functional redundancy. Genetic interaction analysis indicated that SPX3/5 are functional repressors of OsPHR2 (PHR2), the rice orthologue of the central regulator AtPHR1 for Pi homeostasis and Pi signalling. These results suggest that the evolution of the additional redundant paralogous SPX genes is beneficial to plants recovering Pi homeostasis after Pi starvation by PHR2 pathway. PMID:24368504

Wu, Ping

2014-01-01

59

Relation of insulin-like growth factor-1 and insulin-like growth factor binding protein-3 levels to growth retardation in extrahepatic portal vein obstruction  

Microsoft Academic Search

Background  Growth retardation has been described in patients with extrahepatic portal vein obstruction (EHPVO). An abnormal growth hormone\\u000a (GH)–insulin-like growth factor (IGF) axis has been postulated as a possible etiology. We compared anthropometric parameters\\u000a and IGF-1 and insulin-like growth factor binding protein-3 (IGFBP-3) levels in patients with EHPVO with their siblings as\\u000a controls.\\u000a \\u000a \\u000a \\u000a Methods and patients  Consecutive patients diagnosed with EHPVO who

Lalit Nihal; Mukta R. Bapat; Pravin Rathi; Nalini S. Shah; Anjana Karvat; Philip Abraham; Shobna J. Bhatia

2009-01-01

60

Derangements of Hippocampal Calcium\\/Calmodulin Dependent Protein Kinase II in a Mouse Model for Angelman Mental Retardation Syndrome  

Microsoft Academic Search

Angelman syndrome (AS) is a disorder of human cognition characterized by severe mental retardation and epilepsy. Recently, a mouse model for AS (Ube3a maternal null mutation) was developed that displays deficits in both context-dependent learning and hippocampal long-term potentiation (LTP). In the present studies, we examined the molecular basis for these LTP and learning deficits. Mutant animals exhibited a significant

Edwin J. Weeber; Yong-Hui Jiang; Ype Elgersma; Andrew W. Varga; Yarimar Carrasquillo; Sarah E. Brown; Jill M. Christian; Banefsheh Mirnikjoo; Alcino Silva; Arthur L. Beaudet; J. David Sweatt

2003-01-01

61

Cell phenotypes of a mutant in the gene encoding a Rad51 paralog in fission yeast  

Microsoft Academic Search

The discovery of three Rad51 paralogs in Saccharomyces cerevisiae (Rad55, Rad57, and Dmc1), four in Schizosaccharomyces pombe (Rhp55, Rhp57, Rlp1, and Dmc1), and six in human (Rad51B, Rad51C, Rad51D, Xrcc2, Xrcc3, and Dmc1) indicate the functional\\u000a diversity and specialization of RecA-like proteins in the line from the lower to higher organisms. This paper reports characterization\\u000a of a number of mitotic

A. N. Sultanova; A. F. Salakhova; V. I. Bashkirov; F. K. Khasanov

2007-01-01

62

Interactions involving the Rad51 paralogs Rad51C and XRCC3 in human cells  

Microsoft Academic Search

Homologous recombinational repair of DNA double- strand breaks and crosslinks in human cells is likely to require Rad51 and the five Rad51 paralogs (XRCC2, XRCC3, Rad51B\\/Rad51L1, Rad51C\\/Rad51L2 and Rad51D\\/Rad51L3), as has been shown in chicken and rodent cells. Previously, we reported on the inter- actions among these proteins using baculovirus and two- and three-hybrid yeast systems. To test for inter-

Claudia Wiese; David W. Collins; Joanna S. Albala; Larry H. Thompson; Amy Kronenberg; David Schild

2002-01-01

63

Nonredundant and locus-specific gene repression functions of PRC1 paralog family members in human hematopoietic stem/progenitor cells.  

PubMed

The Polycomb group (PcG) protein BMI1 is a key factor in regulating hematopoietic stem cell (HSC) and leukemic stem cell self-renewal and functions in the context of the Polycomb repressive complex 1 (PRC1). In humans, each of the 5 subunits of PRC1 has paralog family members of which many reside in PRC1 complexes, likely in a mutually exclusive manner, pointing toward a previously unanticipated complexity of Polycomb-mediated silencing. We used an RNA interference screening approach to test the functionality of these paralogs in human hematopoiesis. Our data demonstrate a lack of redundancy between various paralog family members, suggestive of functional diversification between PcG proteins. By using an in vivo biotinylation tagging approach followed by liquid chromatography-tandem mass spectrometry to identify PcG interaction partners, we confirmed the existence of multiple specific PRC1 complexes. We find that CBX2 is a nonredundant CBX paralog vital for HSC and progenitor function that directly regulates the expression of the cyclin-dependent kinase inhibitor p21, independently of BMI1 that dominantly controls expression of the INK4A/ARF locus. Taken together, our data show that different PRC1 paralog family members have nonredundant and locus-specific gene regulatory activities that are essential for human hematopoiesis. PMID:23349393

van den Boom, Vincent; Rozenveld-Geugien, Marjan; Bonardi, Francesco; Malanga, Donatella; van Gosliga, Djoke; Heijink, Anne Margriet; Viglietto, Giuseppe; Morrone, Giovanni; Fusetti, Fabrizia; Vellenga, Edo; Schuringa, Jan Jacob

2013-03-28

64

Identification of pathways, gene networks and paralogous gene families in Daphnia pulex responding to exposure to the toxic cyanobacterium Microcystis aeruginosa  

PubMed Central

Although cyanobacteria produce a wide range of natural toxins that impact aquatic organisms, food webs and water quality, the mechanisms of toxicity are still insufficiently understood. Here, we implemented a whole-genome expression microarray to identify pathways, gene networks and paralogous gene families responsive to Microcystis stress in Daphnia pulex. Therefore, neonates of a sensitive isolate were given a diet contaminated with Microcystis to contrast with those given a control diet for sixteen days. The microarray revealed 2247 differentially expressed (DE) genes (7.6% of the array) in response to Microcystis, of which 17% are lineage specific( i.e., these genes have no detectable homology to any other gene in currently available databases) and 49% are gene duplicates (paralogs). We identified four pathways/gene networks and eight paralogous gene families affected by Microcystis. Differential regulation of the ribosome, including 3 paralogous gene families encoding 40S, 60S and mitochondrial ribosomal proteins, suggests an impact of Microcystis on protein synthesis of D. pulex. In addition, differential regulation of the oxidative phosphorylation pathway (including the NADH ubquinone oxidoreductase gene family) and the trypsin paralogous gene family (a major component of the digestive system in D. pulex) could explain why fitness is reduced based on energy budget considerations. PMID:22799445

Asselman, Jana; De Coninck, Dieter IM; Glaholt, Stephen; Colbourne, John K; Janssen, Colin R; Shaw, Joseph R; De Schamphelaere, Karel AC

2013-01-01

65

Rad51 paralogs Rad55-Rad57 balance the anti-recombinase Srs2 in Rad51 filament formation  

PubMed Central

Homologous recombination is a high-fidelity DNA repair pathway. Besides a critical role in accurate chromosome segregation during meiosis, recombination functions in DNA repair and in the recovery of stalled or broken replication forks to ensure genomic stability. In contrast, inappropriate recombination contributes to genomic instability, leading to loss of heterozygosity, chromosome rearrangements, and cell death. The RecA/UvsX/RadA/Rad51 family of proteins catalyzes the signature reactions of recombination, homology search and DNA strand invasion 1,2. Eukaryotes also possess Rad51 paralogs, whose exact role in recombination remains to be defined 3. Here we show that the budding yeast Rad51 paralogs, the Rad55-Rad57 heterodimer, counteract the anti-recombination activity of the Srs2 helicase. Rad55-Rad57 associate with the Rad51-ssDNA filament, rendering it more stable than a nucleoprotein filament containing Rad51 alone. The Rad51/Rad55-Rad57 co-filament resists disruption by the Srs2 anti-recombinase by blocking Srs2 translocation involving a direct protein interaction between Rad55-Rad57 and Srs2. Our results demonstrate an unexpected role of the Rad51 paralogs in stabilizing the Rad51 filament against a biologically important antagonist, the Srs2 anti-recombination helicase. The biological significance of this mechanism is indicated by a complete suppression of the ionizing radiation sensitivity of rad55 or rad57 mutants by concomitant deletion of SRS2, as expected for biological antagonists. We propose that the Rad51 presynaptic filament is a meta-stable reversible intermediate, whose assembly and disassembly is governed by the balance between Rad55-Rad57 and Srs2, providing a key regulatory mechanism controlling the initiation of homologous recombination. These data provide a paradigm for the potential function of the human RAD51 paralogs, which are known to be involved in cancer predisposition and human disease. PMID:22020281

Liu, Jie; Renault, Ludovic; Veaute, Xavier; Fabre, Francis; Stahlberg, Henning; Heyer, Wolf-Dietrich

2011-01-01

66

The fragile X mental retardation protein is associated with poly(A)+ mRNA in actively translating polyribosomes  

Microsoft Academic Search

The fragile X syndrome results from a transcriptional silencing of the FMR1 gene and the absence of its encoded protein. FMRP is a cytoplasmic RNA-binding protein, whose specific cellular function is still unknown. We present evidence that virtually all detectable cytoplasmic FMRP in mouse NIH 3T3 and human HeLa cells is found strictly in association with mRNA in actively translating

François Corbin; Marlène Bouillon; Anny Fortin; Stanislas Morin; François Rousseau; Edouard W. Khandjian

1997-01-01

67

On the role of AtDMC1, AtRAD51 and its paralogs during Arabidopsis meiosis  

PubMed Central

Meiotic recombination plays a critical role in achieving accurate chromosome segregation and increasing genetic diversity. Many studies, mostly in yeast, have provided important insights into the coordination and interplay between the proteins involved in the homologous recombination pathway, especially the recombinase RAD51 and the meiosis-specific DMC1. Here we summarize the current progresses on the function of both recombinases and the CX3 complex encoded by AtRAD51 paralogs, in the plant model species Arabidopsis thaliana. Similarities and differences respect to the function of these proteins in other organisms are also indicated. PMID:24596572

Pradillo, Monica; Varas, Javier; Oliver, Cecilia; Santos, Juan L.

2014-01-01

68

Mildly Retarded Adults: Their Attitudes Toward Retardation  

ERIC Educational Resources Information Center

Responses to a 40-item questionnaire distributed to 50 mildly mentally retarded (MR) adults indicate that the majority possess accurate information about MR, hold realistic attitudes toward their own needs and abilities, and advocate community integration of the retarded. (Author/JG)

Gan, Jennifer; And Others

1977-01-01

69

Intense and specialized dendritic localization of the fragile X mental retardation protein in binaural brainstem neurons: a comparative study in the alligator, chicken, gerbil, and human.  

PubMed

Neuronal dendrites are structurally and functionally dynamic in response to changes in afferent activity. The fragile X mental retardation protein (FMRP) is an mRNA binding protein that regulates activity-dependent protein synthesis and morphological dynamics of dendrites. Loss and abnormal expression of FMRP occur in fragile X syndrome (FXS) and some forms of autism spectrum disorders. To provide further understanding of how FMRP signaling regulates dendritic dynamics, we examined dendritic expression and localization of FMRP in the reptilian and avian nucleus laminaris (NL) and its mammalian analogue, the medial superior olive (MSO), in rodents and humans. NL/MSO neurons are specialized for temporal processing of low-frequency sounds for binaural hearing, which is impaired in FXS. Protein BLAST analyses first demonstrate that the FMRP amino acid sequences in the alligator and chicken are highly similar to human FMRP with identical mRNA-binding and phosphorylation sites, suggesting that FMRP functions similarly across vertebrates. Immunocytochemistry further reveals that NL/MSO neurons have very high levels of dendritic FMRP in low-frequency hearing vertebrates including alligator, chicken, gerbil, and human. Remarkably, dendritic FMRP in NL/MSO neurons often accumulates at branch points and enlarged distal tips, loci known to be critical for branch-specific dendritic arbor dynamics. These observations support an important role for FMRP in regulating dendritic properties of binaural neurons that are essential for low-frequency sound localization and auditory scene segregation, and support the relevance of studying this regulation in nonhuman vertebrates that use low frequencies in order to further understand human auditory processing disorders. PMID:24318628

Wang, Yuan; Sakano, Hitomi; Beebe, Karisa; Brown, Maile R; de Laat, Rian; Bothwell, Mark; Kulesza, Randy J; Rubel, Edwin W

2014-06-15

70

Oligosaccharyltransferase-subunit mutations in nonsyndromic mental retardation.  

PubMed

Mental retardation (MR) is the most frequent handicap among children and young adults. Although a large proportion of X-linked MR genes have been identified, only four genes responsible for autosomal-recessive nonsyndromic MR (AR-NSMR) have been described so far. Here, we report on two genes involved in autosomal-recessive and X-linked NSMR. First, autozygosity mapping in two sibs born to first-cousin French parents led to the identification of a region on 8p22-p23.1. This interval encompasses the gene N33/TUSC3 encoding one subunit of the oligosaccharyltransferase (OTase) complex, which catalyzes the transfer of an oligosaccharide chain on nascent proteins, the key step of N-glycosylation. Sequencing N33/TUSC3 identified a 1 bp insertion, c.787_788insC, resulting in a premature stop codon, p.N263fsX300, and leading to mRNA decay. Surprisingly, glycosylation analyses of patient fibroblasts showed normal N-glycan synthesis and transfer, suggesting that normal N-glycosylation observed in patient fibroblasts may be due to functional compensation. Subsequently, screening of the X-linked N33/TUSC3 paralog, the IAP gene, identified a missense mutation (c.932T-->G, p.V311G) in a family with X-linked NSMR. Recent studies of fucosylation and polysialic-acid modification of neuronal cell-adhesion glycoproteins have shown the critical role of glycosylation in synaptic plasticity. However, our data provide the first demonstration that a defect in N-glycosylation can result in NSMR. Together, our results demonstrate that fine regulation of OTase activity is essential for normal cognitive-function development, providing therefore further insights to understand the pathophysiological bases of MR. PMID:18455129

Molinari, Florence; Foulquier, François; Tarpey, Patrick S; Morelle, Willy; Boissel, Sarah; Teague, Jon; Edkins, Sarah; Futreal, P Andrew; Stratton, Michael R; Turner, Gillian; Matthijs, Gert; Gecz, Jozef; Munnich, Arnold; Colleaux, Laurence

2008-05-01

71

SPOCS: Software for Predicting and Visualizing Orthology/Paralogy Relationships Among Genomes  

SciTech Connect

At the rate that prokaryotic genomes can now be generated, comparative genomics studies require a flexible method for quickly and accurately predicting orthologs among the rapidly changing set of genomes available. SPOCS implements a graph-based ortholog prediction method to generate a simple tab-delimited table of orthologs and in addition, html files that provide a visualization of the predicted ortholog/paralog relationships to which gene/protein expression metadata may be overlaid. AVAILABILITY AND IMPLEMENTATION: A SPOCS web application is freely available at http://cbb.pnnl.gov/portal/tools/spocs.html. Source code for Linux systems is also freely available under an open source license at http://cbb.pnnl.gov/portal/software/spocs.html; the Boost C++ libraries and BLAST are required.

Curtis, Darren S.; Phillips, Aaron R.; Callister, Stephen J.; Conlan, Sean; McCue, Lee Ann

2013-10-15

72

SPOCS: software for predicting and visualizing orthology/paralogy relationships among genomes  

PubMed Central

Summary: At the rate that prokaryotic genomes can now be generated, comparative genomics studies require a flexible method for quickly and accurately predicting orthologs among the rapidly changing set of genomes available. SPOCS implements a graph-based ortholog prediction method to generate a simple tab-delimited table of orthologs and in addition, html files that provide a visualization of the predicted ortholog/paralog relationships to which gene/protein expression metadata may be overlaid. Availability and Implementation: A SPOCS web application is freely available at http://cbb.pnnl.gov/portal/tools/spocs.html. Source code for Linux systems is also freely available under an open source license at http://cbb.pnnl.gov/portal/software/spocs.html; the Boost C++ libraries and BLAST are required. Contact: leeann.mccue@pnnl.gov PMID:23956303

Curtis, Darren S.; Phillips, Aaron R.; Callister, Stephen J.; Conlan, Sean; McCue, Lee Ann

2013-01-01

73

Exogenous Expression of Heat Shock Protein 90kDa Retards the Cell Cycle and Impairs the Heat Shock Response  

Microsoft Academic Search

The 90-kDa heat shock protein, HSP90, is an abundant molecular chaperone which functions in cellular homeostasis in prokaryotes and eukaryotes. It is well known that HSP90 plays a critical and indispensable role in regulating cell growth through modulations of various signal transduction pathways, but its roles in cell cycle control are not so well known. We transferred human HSP90 (wild-type

Chen Zhao; Akinori Hashiguchi; Kensuke Kondoh; Wenlin Du; Jun-ichi Hata; Taketo Yamada

2002-01-01

74

Identification of Mutations in TRAPPC9, which Encodes the NIK- and IKK-?-Binding Protein, in Nonsyndromic Autosomal-Recessive Mental Retardation  

PubMed Central

Mental retardation/intellectual disability is a devastating neurodevelopmental disorder with serious impact on affected individuals and their families, as well as on health and social services. It occurs with a prevalence of ?2%, is an etiologically heterogeneous condition, and is frequently the result of genetic aberrations. Autosomal-recessive forms of nonsyndromic MR (NS-ARMR) are believed to be common, yet only five genes have been identified. We have used homozygosity mapping to search for the gene responsible for NS-ARMR in a large Pakistani pedigree. Using Affymetrix 5.0 single nucleotide polymorphism (SNP) microarrays, we identified a 3.2 Mb region on 8q24 with a continuous run of 606 homozygous SNPs shared among all affected members of the family. Additional genotype data from microsatellite markers verified this, allowing us to calculate a two-point LOD score of 5.18. Within this region, we identified a truncating homozygous mutation, R475X, in exon 7 of the gene TRAPPC9. In a second large NS-ARMR/ID family, previously linked to 8q24 in a study of Iranian families, we identified a 4 bp deletion within exon 14 of TRAPPC9, also segregating with the phenotype and truncating the protein. This gene encodes NIK- and IKK-?-binding protein (NIBP), which is involved in the NF-?B signaling pathway and directly interacts with IKK-? and MAP3K14. Brain magnetic resonance imaging of affected individuals indicates the presence of mild cerebral white matter hypoplasia. Microcephaly is present in some but not all affected individuals. Thus, to our knowledge, this is the sixth gene for NS-ARMR to be discovered. PMID:20004765

Mir, Asif; Kaufman, Liana; Noor, Abdul; Motazacker, Mahdi M.; Jamil, Talal; Azam, Matloob; Kahrizi, Kimia; Rafiq, Muhammad Arshad; Weksberg, Rosanna; Nasr, Tanveer; Naeem, Farooq; Tzschach, Andreas; Kuss, Andreas W.; Ishak, Gisele E.; Doherty, Dan; Ropers, H. Hilger; Barkovich, A. James; Najmabadi, Hossein; Ayub, Muhammad; Vincent, John B.

2009-01-01

75

Interaction specificity, toxicity, and regulation of a paralogous set of ParE/RelE-family toxin-antitoxin systems  

PubMed Central

Summary Toxin-antitoxin (TA) gene cassettes are widely distributed across bacteria, archaea, and bacteriophage. The chromosome of the ?-proteobacterium, Caulobacter crescentus, encodes eight ParE/RelE-superfamily toxins that are organized into operons with their cognate antitoxins. A systematic genetic analysis of these parDE and relBE TA operons demonstrates that seven encode functional toxins. The one exception highlights an example of a non-functional toxin pseudogene. Chromosomally-encoded ParD and RelB proteins function as antitoxins, inhibiting their adjacently-encoded ParE and RelE toxins. However, these antitoxins do not functionally complement each other, even when overexpressed. Transcription of these paralogous TA systems is differentially regulated under distinct environmental conditions. These data support a model in which multiple TA paralogs encoded by a single bacterial chromosome form independent functional units with insulated protein-protein interactions. Further characterization of the parDE1 system at the single-cell level reveals that ParE1 toxin functions to inhibit cell division but not cell growth; residues at the C-terminus of ParE1 are critical for its stability and toxicity. While continuous ParE1 overexpression results in a substantial loss in cell viability at the population level, a fraction of cells escape toxicity, providing evidence that ParE1 toxicity is not uniform within clonal cell populations. PMID:20487277

Fiebig, Aretha; Rojas, Cyd Marie Castro; Siegal-Gaskins, Dan; Crosson, Sean

2010-01-01

76

PROGRAM PLANNING FOR RETARDED CLASSES.  

ERIC Educational Resources Information Center

THIS CURRICULUM GUIDE PRESENTS FIVE PROGRAMS FOR MENTALLY HANDICAPPED STUDENTS--PRESCHOOL RETARDED, SEVERELY RETARDED, PRIMARY EDUCABLE RETARDED, INTERMEDIATE EDUCABLE RETARDED, AND JUNIOR AND SENIOR EDUCABLE RETARDED. SOCIAL STUDIES, LANGUAGE, ARITHMETIC, MUSIC, ART AND CRAFTS, PHYSICAL EDUCATION, SCIENCE, WRITING, SPELLING, OCCUPATIONAL…

Dade County Public Schools, Miami, FL.

77

Mental Retardation in Perspective.  

ERIC Educational Resources Information Center

This monograph presents a general introduction to the history, classification, and characteristics of mental retardation. It begins with a discussion of the history of mental retardation from ancient Greece and Rome to the present. The beginnings of special education are traced to the early 19th century in Europe. Major influences in treatment of…

Horvath, Michael; And Others

78

The RAB family GTPase Rab1A from Plasmodium falciparum defines a unique paralog shared by chromalveolates and rhizaria.  

PubMed

The RAB GTPases, which are involved in regulation of endomembrane trafficking, exhibit a complex but incompletely understood evolutionary history. We elucidated the evolution of the RAB1 subfamily ancestrally implicated in the endoplasmic reticulum-to-Golgi traffic. We found that RAB1 paralogs have been generated over the course of eukaryotic evolution, with some duplications coinciding with the advent of major eukaryotic lineages (e.g. Metazoa, haptophytes). We also identified a unique, derived RAB1 paralog, orthologous to the Plasmodium Rab1A, that occurs in stramenopiles, alveolates, and Rhizaria, represented by the chlorarachniophyte Gymnochlora stellata. This finding is consistent with the recently documented existence of a major eukaryotic clade ("SAR") comprising these three lineages. We further found a Rab1A-like protein in the cryptophyte Guillardia theta, but it exhibits unusual features among RAB proteins: absence of a C-terminal prenylation motif and an N-terminal extension with two MSP domains; and its phylogenetic relationships could not be established convincingly due to its divergent nature. Our results nevertheless point to a unique membrane trafficking pathway shared by at least some lineages of chromalveolates and Rhizaria, an insight that has implications towards interpreting the early evolution of eukaryotes and the endomembrane system. PMID:19602080

Elias, Marek; Patron, Nicola J; Keeling, Patrick J

2009-01-01

79

Faster evolving Drosophila paralogs lose expression rate and ubiquity and accumulate more non-synonymous SNPs  

PubMed Central

Background Duplicated genes can indefinately persist in genomes if either both copies retain the original function due to dosage benefit (gene conservation), or one of the copies assumes a novel function (neofunctionalization), or both copies become required to perform the function previously accomplished by a single copy (subfunctionalization), or through a combination of these mechanisms. Different models of duplication retention imply different predictions about substitution rates in the coding portion of paralogs and about asymmetry of these rates. Results We analyse sequence evolution asymmetry in paralogs present in 12 Drosophila genomes using the nearest non-duplicated orthologous outgroup as a reference. Those paralogs present in D. melanogaster are analysed in conjunction with the asymmetry of expression rate and ubiquity and of segregating non-synonymous polymorphisms in the same paralogs. Paralogs accumulate substitutions, on average, faster than their nearest singleton orthologs. The distribution of paralogs’ substitution rate asymmetry is overdispersed relative to that of orthologous clades, containing disproportionally more unusually symmetric and unusually asymmetric clades. We show that paralogs are more asymmetric in: a) clades orthologous to highly constrained singleton genes; b) genes with high expression level; c) genes with ubiquitous expression and d) non-tandem duplications. We further demonstrate that, in each asymmetrically evolving pair of paralogs, the faster evolving member of the pair tends to have lower average expression rate, lower expression uniformity and higher frequency of non-synonymous SNPs than its slower evolving counterpart. Conclusions Our findings are consistent with the hypothesis that many duplications in Drosophila are retained despite stabilising selection being more relaxed in one of the paralogs than in the other, suggesting a widespread unfinished pseudogenization. This phenomenon is likely to make detection of neo- and subfunctionalization signatures difficult, as these models of duplication retention also predict asymmetries in substitution rates and expression profiles. Reviewers This article has been reviewed by Dr. Jia Zeng (nominated by Dr. I. King Jordan), Dr. Fyodor Kondrashov and Dr. Yuri Wolf. PMID:24438455

2014-01-01

80

Parallel reduction in expression, but no loss of functional constraint, in two opsin paralogs within cave populations of Gammarus minus (Crustacea: Amphipoda)  

PubMed Central

Background Gammarus minus, a freshwater amphipod living in the cave and surface streams in the eastern USA, is a premier candidate for studying the evolution of troglomorphic traits such as pigmentation loss, elongated appendages, and reduced eyes. In G. minus, multiple pairs of genetically related, physically proximate cave and surface populations exist which exhibit a high degree of intraspecific morphological divergence. The morphology, ecology, and genetic structure of these sister populations are well characterized, yet the genetic basis of their morphological divergence remains unknown. Results We used degenerate PCR primers designed to amplify opsin genes within the subphylum Crustacea and discovered two distinct opsin paralogs (average inter-paralog protein divergence???20%) in the genome of three independently derived pairs of G. minus cave and surface populations. Both opsin paralogs were found to be related to other crustacean middle wavelength sensitive opsins. Low levels of nucleotide sequence variation (< 1% within populations) were detected in both opsin genes, regardless of habitat, and dN/dS ratios did not indicate a relaxation of functional constraint in the cave populations with reduced or absent eyes. Maximum likelihood analyses using codon-based models also did not detect a relaxation of functional constraint in the cave lineages. We quantified expression level of both opsin genes and found that the expression of both paralogs was significantly reduced in all three cave populations relative to their sister surface populations. Conclusions The concordantly lowered expression level of both opsin genes in cave populations of G. minus compared to sister surface populations, combined with evidence for persistent purifying selection in the cave populations, is consistent with an unspecified pleiotropic function of opsin proteins. Our results indicate that phototransduction proteins such as opsins may have retained their function in cave-adapted organisms because they may play a pleiotropic role in other important processes that are unrelated to vision. PMID:23617561

2013-01-01

81

Fire-Retardant, Decorative Inks  

NASA Technical Reports Server (NTRS)

Effectiveness of fire-retardant additives evaluated. Fire retardance of decorative acrylic printing inks for aircraft interiors enhanced by certain commercial and experimental fire-retardant additives, according to study.

Kourtides, D.; Nir, Z.; Mikroyannidis, J.

1987-01-01

82

Splign: algorithms for computing spliced alignments with identification of paralogs  

PubMed Central

Background The computation of accurate alignments of cDNA sequences against a genome is at the foundation of modern genome annotation pipelines. Several factors such as presence of paralogs, small exons, non-consensus splice signals, sequencing errors and polymorphic sites pose recognized difficulties to existing spliced alignment algorithms. Results We describe a set of algorithms behind a tool called Splign for computing cDNA-to-Genome alignments. The algorithms include a high-performance preliminary alignment, a compartment identification based on a formally defined model of adjacent duplicated regions, and a refined sequence alignment. In a series of tests, Splign has produced more accurate results than other tools commonly used to compute spliced alignments, in a reasonable amount of time. Conclusion Splign's ability to deal with various issues complicating the spliced alignment problem makes it a helpful tool in eukaryotic genome annotation processes and alternative splicing studies. Its performance is enough to align the largest currently available pools of cDNA data such as the human EST set on a moderate-sized computing cluster in a matter of hours. The duplications identification (compartmentization) algorithm can be used independently in other areas such as the study of pseudogenes. Reviewers This article was reviewed by: Steven Salzberg, Arcady Mushegian and Andrey Mironov (nominated by Mikhail Gelfand). PMID:18495041

Kapustin, Yuri; Souvorov, Alexander; Tatusova, Tatiana; Lipman, David

2008-01-01

83

Origins and functional diversification of salinity-responsive Na(+) , K(+) ATPase ?1 paralogs in salmonids.  

PubMed

The Salmoniform whole-genome duplication is hypothesized to have facilitated the evolution of anadromy, but little is known about the contribution of paralogs from this event to the physiological performance traits required for anadromy, such as salinity tolerance. Here, we determined when two candidate, salinity-responsive paralogs of the Na(+) , K(+) ATPase ? subunit (?1a and ?1b) evolved and studied their evolutionary trajectories and tissue-specific expression patterns. We found that these paralogs arose during a small-scale duplication event prior to the Salmoniform, but after the teleost, whole-genome duplication. The 'freshwater paralog' (?1a) is primarily expressed in the gills of Salmoniformes and an unduplicated freshwater sister species (Esox lucius) and experienced positive selection in the freshwater ancestor of Salmoniformes and Esociformes. Contrary to our predictions, the 'saltwater paralog' (?1b), which is more widely expressed than ?1a, did not experience positive selection during the evolution of anadromy in the Coregoninae and Salmonine. To determine whether parallel mutations in Na(+) , K(+) ATPase ?1 may contribute to salinity tolerance in other fishes, we studied independently evolved salinity-responsive Na(+) , K(+) ATPase ?1 paralogs in Anabas testudineus and Oreochromis mossambicus. We found that a quarter of the mutations occurring between salmonid ?1a and ?1b in functionally important sites also evolved in parallel in at least one of these species. Together, these data argue that paralogs contributing to salinity tolerance evolved prior to the Salmoniform whole-genome duplication and that strong selection and/or functional constraints have led to parallel evolution in salinity-responsive Na(+) , K(+) ATPase ?1 paralogs in fishes. PMID:24917532

Dalziel, Anne C; Bittman, Jesse; Mandic, Milica; Ou, Michelle; Schulte, Patricia M

2014-07-01

84

Fire retardant polyisocyanurate foam  

NASA Technical Reports Server (NTRS)

Fire retardant properties of low density polymer foam are increased. Foam has pendant nitrile groups which form thermally-stable heterocyclic structures at temperature below degradation temperature of urethane linkages.

Riccitiello, S. R.; Parker, J. A.

1972-01-01

85

The zebrafish genome encodes the largest vertebrate repertoire of functional aquaporins with dual paralogy and substrate specificities similar to mammals  

PubMed Central

Background Aquaporins are integral membrane proteins that facilitate the transport of water and small solutes across cell membranes. These proteins are vital for maintaining water homeostasis in living organisms. In mammals, thirteen aquaporins (AQP0-12) have been characterized, but in lower vertebrates, such as fish, the diversity, structure and substrate specificity of these membrane channel proteins are largely unknown. Results The screening and isolation of transcripts from the zebrafish (Danio rerio) genome revealed eighteen sequences structurally related to the four subfamilies of tetrapod aquaporins, i.e., aquaporins (AQP0, -1 and -4), water and glycerol transporters or aquaglyceroporins (Glps; AQP3 and AQP7-10), a water and urea transporter (AQP8), and two unorthodox aquaporins (AQP11 and -12). Phylogenetic analyses of nucleotide and deduced amino acid sequences demonstrated dual paralogy between teleost and human aquaporins. Three of the duplicated zebrafish isoforms have unlinked loci, two have linked loci, while DrAqp8 was found in triplicate across two chromosomes. Genomic sequencing, structural analysis, and maximum likelihood reconstruction, further revealed the presence of a putative pseudogene that displays hybrid exons similar to tetrapod AQP5 and -1. Ectopic expression of the cloned transcripts in Xenopus laevis oocytes demonstrated that zebrafish aquaporins and Glps transport water or water, glycerol and urea, respectively, whereas DrAqp11b and -12 were not functional in oocytes. Contrary to humans and some rodents, intrachromosomal duplicates of zebrafish AQP8 were water and urea permeable, while the genomic duplicate only transported water. All aquaporin transcripts were expressed in adult tissues and found to have divergent expression patterns. In some tissues, however, redundant expression of transcripts encoding two duplicated paralogs seems to occur. Conclusion The zebrafish genome encodes the largest repertoire of functional vertebrate aquaporins with dual paralogy to human isoforms. Our data reveal an early and specific diversification of these integral membrane proteins at the root of the crown-clade of Teleostei. Despite the increase in gene copy number, zebrafish aquaporins mostly retain the substrate specificity characteristic of the tetrapod counterparts. Based upon the integration of phylogenetic, genomic and functional data we propose a new classification for the piscine aquaporin superfamily. PMID:20149227

2010-01-01

86

HELQ promotes RAD51 paralog-dependent repair to avert germ cell attrition and tumourigenesis  

PubMed Central

Repair of interstrand crosslinks (ICLs) requires the coordinate action of the intra-S phase checkpoint and the Fanconi Anemia (FA) pathway, which promote ICL incision, translesion synthesis, and homologous recombination (reviewed in 1,2). Previous studies have implicated the 3?-5? superfamily 2 helicase HELQ/Hel308 in ICL repair in D. melanogaster (known as Mus301 or Spn-C3) and C. elegans (known as Helq-1 or Hel-3084). While in vitro analysis suggests that HELQ preferentially unwinds synthetic replication fork substrates with 3? ssDNA overhangs and also disrupts protein/DNA interactions while translocating along DNA5,6, little is known regarding its functions in mammalian organisms. Here we report that HELQ helicase-deficient mice exhibit subfertility, germ cell attrition, ICL sensitivity and tumour predisposition, with HelQ heterozygous mice exhibiting a similar, albeit less severe, phenotype than the null, indicative of haploinsufficiency. We establish that HELQ interacts directly with the RAD51 paralog complex, BCDX2, and functions in parallel to the FA pathway to promote efficient HR at damaged replication forks. Thus, our results reveal a critical role for HELQ in replication-coupled DNA repair, germ cell maintenance and tumour suppression in mammals. PMID:24005329

Adelman, Carrie A.; Lolo, Rafal L.; Birkbak, Nicolai J.; Murina, Olga; Matsuzaki, Kenichiro; Horejsi, Zuzana; Parmar, Kalindi; Borel, Valerie; Skehel, J. Mark; Stamp, Gordon; D'Andrea, Alan; Sartori, Alessandro A.; Swanton, Charles; Boulton, Simon J.

2013-01-01

87

Sost and its paralog Sostdc1 coordinate digit number in a Gli3-dependent manner.  

PubMed

WNT signaling is critical in most aspects of skeletal development and homeostasis, and antagonists of WNT signaling are emerging as key regulatory proteins with great promise as therapeutic agents for bone disorders. Here we show that Sost and its paralog Sostdc1 emerged through ancestral genome duplication and their expression patterns have diverged to delineate non-overlapping domains in most organ systems including musculoskeletal, cardiovascular, nervous, digestive, reproductive and respiratory. In the developing limb, Sost and Sostdc1 display dynamic expression patterns with Sost being restricted to the distal ectoderm and Sostdc1 to the proximal ectoderm and the mesenchyme. While Sostdc1(-/-) mice lack any obvious limb or skeletal defects, Sost(-/-) mice recapitulate the hand defects described for Sclerosteosis patients. However, elevated WNT signaling in Sost(-/-); Sostdc1(-/-) mice causes misregulation of SHH signaling, ectopic activation of Sox9 in the digit 1 field and preaxial polydactyly in a Gli1- and Gli3-dependent manner. In addition, we show that the syndactyly documented in Sclerosteosis is present in both Sost(-/-) and Sost(-/-); Sostdc1(-/-) mice, and is driven by misregulation of Fgf8 in the AER, a region lacking Sost and Sostdc1 expression. This study highlights the complexity of WNT signaling in skeletal biology and disease and emphasizes how redundant mechanism and non-cell autonomous effects can synergize to unveil new intricate phenotypes caused by elevated WNT signaling. PMID:23994639

Collette, Nicole M; Yee, Cristal S; Murugesh, Deepa; Sebastian, Aimy; Taher, Leila; Gale, Nicholas W; Economides, Aris N; Harland, Richard M; Loots, Gabriela G

2013-11-01

88

Sost and its paralog Sostdc1 coordinate digit number in a Gli3-dependent manner?  

PubMed Central

WNT signaling is critical in most aspects of skeletal development and homeostasis, and antagonists of WNT signaling are emerging as key regulatory proteins with great promise as therapeutic agents for bone disorders. Here we show that Sost and its paralog Sostdc1 emerged through ancestral genome duplication and their expression patterns have diverged to delineate non-overlapping domains in most organ systems including musculoskeletal, cardiovascular, nervous, digestive, reproductive and respiratory. In the developing limb, Sost and Sostdc1 display dynamic expression patterns with Sost being restricted to the distal ectoderm and Sostdc1 to the proximal ectoderm and the mesenchyme. While Sostdc1–/– mice lack any obvious limb or skeletal defects, Sost–/– mice recapitulate the hand defects described for Sclerosteosis patients. However, elevated WNT signaling in Sost–/–; Sostdc1–/– mice causes misregulation of SHH signaling, ectopic activation of Sox9 in the digit 1 field and preaxial polydactyly in a Gli1- and Gli3-dependent manner. In addition, we show that the syndactyly documented in Sclerosteosis is present in both Sost–/– and Sost–/–; Sostdc1–/– mice, and is driven by misregulation of Fgf8 in the AER, a region lacking Sost and Sostdc1 expression. This study highlights the complexity of WNT signaling in skeletal biology and disease and emphasizes how redundant mechanism and non-cell autonomous effects can synergize to unveil new intricate phenotypes caused by elevated WNT signaling. PMID:23994639

Collette, Nicole M.; Yee, Cristal S.; Murugesh, Deepa; Sebastian, Aimy; Taher, Leila; Gale, Nicholas W.; Economides, Aris N.; Harland, Richard M.; Loots, Gabriela G.

2013-01-01

89

Close association between paralogous multiple isomiRs and paralogous/orthologues miRNA sequences implicates dominant sequence selection across various animal species.  

PubMed

MicroRNAs (miRNAs) are crucial negative regulators of gene expression at the post-transcriptional level. Next-generation sequencing technologies have identified a series of miRNA variants (named isomiRs). In this study, paralogous isomiR assemblies (from the miRNA locus) were systematically analyzed based on data acquired from deep sequencing data sets. Evolutionary analysis of paralogous (members in miRNA gene family in a specific species) and orthologues (across different animal species) miRNAs was also performed. The sequence diversity of paralogous isomiRs was found to be similar to the diversity of paralogous and orthologues miRNAs. Additionally, both isomiRs and paralogous/orthologues miRNAs were implicated in 5' and 3' ends (especially 3' ends), nucleotide substitutions, and insertions and deletions. Generally, multiple isomiRs can be produced from a single miRNA locus, but most of them had lower enrichment levels, and only several dominant isomiR sequences were detected. These dominant isomiR groups were always stable, and one of them would be selected as the most abundant miRNA sequence in specific animal species. Some isomiRs might be consistent to miRNA sequences in some species but not the other. Homologous miRNAs were often detected in similar isomiR repertoires, and showed similar expression patterns, while dominant isomiRs showed complex evolutionary patterns from miRNA sequences across the animal kingdom. These results indicate that the phenomenon of multiple isomiRs is not a random event, but rather the result of evolutionary pressures. The existence of multiple isomiRs enables different species to express advantageous sequences in different environments. Thus, dominant sequences emerge in response to functional and evolutionary pressures, allowing an organism to adapt to complex intra- and extra-cellular events. PMID:23856130

Guo, Li; Zhao, Yang; Zhang, Hui; Yang, Sheng; Chen, Feng

2013-09-25

90

The Impact of Paralogy on Phylogenomic Studies - A Case Study on Annelid Relationships  

PubMed Central

Phylogenomic studies based on hundreds of genes derived from expressed sequence tags libraries are increasingly used to reveal the phylogeny of taxa. A prerequisite for these studies is the assignment of genes into clusters of orthologous sequences. Sophisticated methods of orthology prediction are used in such analyses, but it is rarely assessed whether paralogous sequences have been erroneously grouped together as orthologous sequences after the prediction, and whether this had an impact on the phylogenetic reconstruction using a super-matrix approach. Herein, I tested the impact of paralogous sequences on the reconstruction of annelid relationships based on phylogenomic datasets. Using single-partition analyses, screening for bootstrap support, blast searches and pruning of sequences in the supermatrix, wrongly assigned paralogous sequences were found in eight partitions and the placement of five taxa (the annelids Owenia, Scoloplos, Sthenelais and Eurythoe and the nemertean Cerebratulus) including the robust bootstrap support could be attributed to the presence of paralogous sequences in two partitions. Excluding these sequences resulted in a different, weaker supported placement for these taxa. Moreover, the analyses revealed that paralogous sequences impacted the reconstruction when only a single taxon represented a previously supported higher taxon such as a polychaete family. One possibility of a priori detection of wrongly assigned paralogous sequences could combine 1) a screening of single-partition analyses based on criteria such as nodal support or internal branch length with 2) blast searches of suspicious cases as presented herein. Also possible are a posteriori approaches in which support for specific clades is investigated by comparing alternative hypotheses based on differences in per-site likelihoods. Increasing the sizes of EST libraries will also decrease the likelihood of wrongly assigned paralogous sequences, and in the case of orthology prediction methods like HaMStR it is likewise decreased by using more than one reference taxon. PMID:23667537

Struck, Torsten H.

2013-01-01

91

Phyletic Profiling with Cliques of Orthologs Is Enhanced by Signatures of Paralogy Relationships  

PubMed Central

New microbial genomes are sequenced at a high pace, allowing insight into the genetics of not only cultured microbes, but a wide range of metagenomic collections such as the human microbiome. To understand the deluge of genomic data we face, computational approaches for gene functional annotation are invaluable. We introduce a novel model for computational annotation that refines two established concepts: annotation based on homology and annotation based on phyletic profiling. The phyletic profiling-based model that includes both inferred orthologs and paralogs—homologs separated by a speciation and a duplication event, respectively—provides more annotations at the same average Precision than the model that includes only inferred orthologs. For experimental validation, we selected 38 poorly annotated Escherichia coli genes for which the model assigned one of three GO terms with high confidence: involvement in DNA repair, protein translation, or cell wall synthesis. Results of antibiotic stress survival assays on E. coli knockout mutants showed high agreement with our model's estimates of accuracy: out of 38 predictions obtained at the reported Precision of 60%, we confirmed 25 predictions, indicating that our confidence estimates can be used to make informed decisions on experimental validation. Our work will contribute to making experimental validation of computational predictions more approachable, both in cost and time. Our predictions for 998 prokaryotic genomes include ?400000 specific annotations with the estimated Precision of 90%, ?19000 of which are highly specific—e.g. “penicillin binding,” “tRNA aminoacylation for protein translation,” or “pathogenesis”—and are freely available at http://gorbi.irb.hr/. PMID:23308060

Škunca, Nives; Bošnjak, Matko; Kriško, Anita; Panov, Pan?e; Džeroski, Sašo; Šmuc, Tomislav; Supek, Fran

2013-01-01

92

NLR-associating transcription factor bHLH84 and its paralogs function redundantly in plant immunity.  

PubMed

In plants and animals, nucleotide-binding and leucine-rich repeat domain containing (NLR) immune receptors are utilized to detect the presence or activities of pathogen-derived molecules. However, the mechanisms by which NLR proteins induce defense responses remain unclear. Here, we report the characterization of one basic Helix-loop-Helix (bHLH) type transcription factor (TF), bHLH84, identified from a reverse genetic screen. It functions as a transcriptional activator that enhances the autoimmunity of NLR mutant snc1 (suppressor of npr1-1, constitutive 1) and confers enhanced immunity in wild-type backgrounds when overexpressed. Simultaneously knocking out three closely related bHLH paralogs attenuates RPS4-mediated immunity and partially suppresses the autoimmune phenotypes of snc1, while overexpression of the other two close paralogs also renders strong autoimmunity, suggesting functional redundancy in the gene family. Intriguingly, the autoimmunity conferred by bHLH84 overexpression can be largely suppressed by the loss-of-function snc1-r1 mutation, suggesting that SNC1 is required for its proper function. In planta co-immunoprecipitation revealed interactions between not only bHLH84 and SNC1, but also bHLH84 and RPS4, indicating that bHLH84 associates with these NLRs. Together with previous finding that SNC1 associates with repressor TPR1 to repress negative regulators, we hypothesize that nuclear NLR proteins may interact with both transcriptional repressors and activators during immune responses, enabling potentially faster and more robust transcriptional reprogramming upon pathogen recognition. PMID:25144198

Xu, Fang; Kapos, Paul; Cheng, Yu Ti; Li, Meng; Zhang, Yuelin; Li, Xin

2014-08-01

93

Flame retardant polymeric materials  

SciTech Connect

The flame retardation of polyolefins is the focus of this volume. Methods for reduction of smoke and experimental evaluation of flammability parameters for polymeric materials are discussed. The flammability evaluation methods for textiles and the use of mass spectrometry for analysis of polymers and their degradation products are also presented.

Lewin, M.; Atlas, S.M.; Pearce, E.M.

1982-01-01

94

Monkey Retardate Learning Analysis  

ERIC Educational Resources Information Center

Seven rhesus monkeys reared on diets high in phenylalanine to induce phenylketonuria (PKU--a metabolic disorder associated with mental retardation if untreated) were compared with normal, pair-fed, and younger controls; frontal brain-lesioned monkeys; and those raised on high-tryptophan diets in three object discrimination tasks. (Author)

Chamove, A. S.; Molinaro, T. J.

1978-01-01

95

Counseling Mentally Retarded Couples.  

ERIC Educational Resources Information Center

This paper presents an experimental group model developed for counseling mentally retarded couples. The selection of the group counseling format is explained, group composition and eligibility requirements are described, and initial assessment of individuals and couples is presented. Preliminary sessions, geared toward orienting the couple to the…

Spragg, Paul A.; Miller, Cheryl

96

Teaching Retarded Children about Sex.  

ERIC Educational Resources Information Center

Mentally retarded children need sex education, not only about biological factors involved in sexuality, but also in terms of emotional and social development as well. Ways that parents can prepare retarded youngsters to cope with emerging sexuality are discussed. (PP)

Kempton, Winifred

1983-01-01

97

Characterisation of a novel paralog of scavenger receptor class B member I (SCARB1) in Atlantic salmon (Salmo salar)  

PubMed Central

Background Red flesh colour is a unique trait found in some salmonid genera. Carotenoid pigments are not synthesized de novo in the fish, but are provided by dietary uptake. A better understanding of the molecular mechanisms underlying the cellular uptake and deposition of carotenoids could potentially be used to improve the low muscle deposition rate that is typically found in farmed Atlantic salmon. In addition, from an evolutionary point of view, the establishment and maintenance of this trait is still poorly understood. It has been demonstrated in several species that scavenger receptor class B, member 1 (SCARB1) is involved in intestinal absorption of carotenoids, which makes this gene a possible source of genetic variation in salmonid flesh pigmentation. Results In this study, a novel paralog of SCARB1 (SCARB1-2) was detected through screening for genetic variation in Atlantic salmon SCARB1. Full length SCARB1-2 encodes a protein with 89% identity to Atlantic salmon SCARB1, except for the C-terminal cytoplasmic tail that shows only 12% identity. The most prominent site of SCARB1 mRNA expression was in the mid gut, while a five-fold lower level was detected in Atlantic salmon skeletal muscle and liver. The SCARB1-2 mRNA was equally expressed in liver, muscle and mid gut, and at a lower level than SCARB1 mRNA. A total of seven different SCARB1-2 alleles comprising repetitive enhancer of zeste motifs (EZH2) were identified in the founding parents of a resource Atlantic salmon population. We mapped the SCARB1-2 paralog to a region on Atlantic salmon chromosome 1, containing a putative QTL for flesh colour. Addition of the SCARB1-2 marker increased the significance of this QTL, however the large confidence interval surrounding the QTL precludes confirmation of SCARB1-2 as a causative gene underlying variation in this trait. Conclusion We have characterised a novel paralog of SCARB1 (SCARB1-2), have mapped it to Atlantic salmon chromosome 1 and have described its expression in various tissues. Mapping with SCARB1-2 alleles added further evidence for a QTL affecting flesh colour on this chromosome, however further studies are needed to confirm a functional role for this gene in flesh colour pigmentation. PMID:21619714

2011-01-01

98

Systematic variation in the pattern of gene paralog retention between the teleost superorders Ostariophysi and Acanthopterygii.  

PubMed

Teleost fish underwent whole-genome duplication around 450 Ma followed by diploidization and loss of 80-85% of the duplicated genes. To identify a deep signature of this teleost-specific whole-genome duplication (TSGD), we searched for duplicated genes that were systematically and uniquely retained in one or other of the superorders Ostariophysi and Acanthopterygii. TSGD paralogs comprised 17-21% of total gene content. Some 2.6% (510) of TSGD paralogs were present as pairs in the Ostariophysi genomes of Danio rerio (Cypriniformes) and Astyanax mexicanus (Characiformes) but not in species from four orders of Acanthopterygii (Gasterosteiformes, Gasterosteus aculeatus; Tetraodontiformes, Tetraodon nigroviridis; Perciformes, Oreochromis niloticus; and Beloniformes, Oryzias latipes) where a single copy was identified. Similarly, 1.3% (418) of total gene number represented cases where TSGD paralogs pairs were systematically retained in the Acanthopterygian but conserved as a single copy in Ostariophysi genomes. We confirmed the generality of these results by phylogenetic and synteny analysis of 40 randomly selected linage-specific paralogs (LSPs) from each superorder and completed with the transcriptomes of three additional Ostariophysi species (Ictalurus punctatus [Siluriformes], Sinocyclocheilus species [Cypriniformes], and Piaractus mesopotamicus [Characiformes]). No chromosome bias was detected in TSGD paralog retention. Gene ontology (GO) analysis revealed significant enrichment of GO terms relative to the human GO SLIM database for "growth," "Cell differentiation," and "Embryo development" in Ostariophysi and for "Transport," "Signal Transduction," and "Vesicle mediated transport" in Acanthopterygii. The observed patterns of paralog retention are consistent with different diploidization outcomes having contributed to the evolution/diversification of each superorder. PMID:24732281

Garcia de la Serrana, Daniel; Mareco, Edson A; Johnston, Ian A

2014-04-01

99

Systematic Variation in the Pattern of Gene Paralog Retention between the Teleost Superorders Ostariophysi and Acanthopterygii  

PubMed Central

Teleost fish underwent whole-genome duplication around 450 Ma followed by diploidization and loss of 80–85% of the duplicated genes. To identify a deep signature of this teleost-specific whole-genome duplication (TSGD), we searched for duplicated genes that were systematically and uniquely retained in one or other of the superorders Ostariophysi and Acanthopterygii. TSGD paralogs comprised 17–21% of total gene content. Some 2.6% (510) of TSGD paralogs were present as pairs in the Ostariophysi genomes of Danio rerio (Cypriniformes) and Astyanax mexicanus (Characiformes) but not in species from four orders of Acanthopterygii (Gasterosteiformes, Gasterosteus aculeatus; Tetraodontiformes, Tetraodon nigroviridis; Perciformes, Oreochromis niloticus; and Beloniformes, Oryzias latipes) where a single copy was identified. Similarly, 1.3% (418) of total gene number represented cases where TSGD paralogs pairs were systematically retained in the Acanthopterygian but conserved as a single copy in Ostariophysi genomes. We confirmed the generality of these results by phylogenetic and synteny analysis of 40 randomly selected linage-specific paralogs (LSPs) from each superorder and completed with the transcriptomes of three additional Ostariophysi species (Ictalurus punctatus [Siluriformes], Sinocyclocheilus species [Cypriniformes], and Piaractus mesopotamicus [Characiformes]). No chromosome bias was detected in TSGD paralog retention. Gene ontology (GO) analysis revealed significant enrichment of GO terms relative to the human GO SLIM database for “growth,” “Cell differentiation,” and “Embryo development” in Ostariophysi and for “Transport,” “Signal Transduction,” and “Vesicle mediated transport” in Acanthopterygii. The observed patterns of paralog retention are consistent with different diploidization outcomes having contributed to the evolution/diversification of each superorder. PMID:24732281

Garcia de la serrana, Daniel; Mareco, Edson A.; Johnston, Ian A.

2014-01-01

100

Teaching the Educable Mentally Retarded.  

ERIC Educational Resources Information Center

The text discusses the behavior, evaluation, and education of mentally retarded children. Harold D. Love presents an overview of the retarded, a description of intelligence and personality tests, and a historical survey of retardation; Virginia Cantrell reviews the educational philosophies and methods of Itard, Seguin, and Montessori. Shirley K.…

Love, Harold D.

101

Mental Retardation, Selected Conference Papers.  

ERIC Educational Resources Information Center

A compilation of selected papers includes the following: comprehensive diagnostic services; pediatric aspects of diagnosis; psychological evaluation of the severely retarded; use of social competency devices; diagnosis of the adult retarded; programing for the severely retarded; nursery school experiences for the trainable; a practical approach to…

Scheerenberger, R.C., Ed.

102

Differential deployment of paralogous Wnt genes in the mouse and chick embryo during development  

PubMed Central

SUMMARY Genes encoding Wnt ligands are crucial in body patterning and are highly conserved among metazoans. Given their conservation at the protein-coding level, it is likely that changes in where and when these genes are active are important in generating evolutionary variations. However, we lack detailed knowledge about how their deployment has diverged. Here, we focus on four Wnt subfamilies (Wnt2, Wnt5, Wnt7, and Wnt8) in mammalian and avian species, consisting of a paralogous gene pair in each, believed to have duplicated in the last common ancestor of vertebrates. We use three-dimensional imaging to capture expression patterns in detail and carry out systematic comparisons. We find evidence of greater divergence between these subgroup paralogues than the respective orthologues, consistent with some level of subfunctionalization/neofunctionalization in the common vertebrate ancestor that has been conserved. However, there were exceptions; in the case of chick Wnt2b, individual sites were shared with both mouse Wnt2 and Wnt2b. We also find greater divergence, between paralogues and orthologues, in some subfamilies (Wnt2 and Wnt8) compared to others (Wnt5 and Wnt7) with the more highly similar expression patterns showing more extensive expression in more structures in the embryo. Wnt8 genes were most restricted and most divergent. Major sites of expression for all subfamilies include CNS, limbs, and facial region, and in general there were more similarities in gene deployment in these territories with divergent patterns featuring more in organs such as heart and gut. A detailed comparison of gene expression patterns in the limb showed similarities in overall combined domains across species with notable differences that may relate to lineage-specific morphogenesis. PMID:23017026

Martin, Audrey; Maher, Stephanie; Summerhurst, Kristen; Davidson, Duncan; Murphy, Paula

2012-01-01

103

Control of Copper Resistance and Inorganic Sulfur Metabolism by Paralogous Regulators in Staphylococcus aureus*  

PubMed Central

All strains of Staphylococcus aureus encode a putative copper-sensitive operon repressor (CsoR) and one other CsoR-like protein of unknown function. We show here that NWMN_1991 encodes a bona fide Cu(I)-inducible CsoR of a genetically unlinked copA-copZ copper resistance operon in S. aureus strain Newman. In contrast, an unannotated open reading frame found between NWMN_0027 and NWMN_0026 (denoted NWMN_0026.5) encodes a CsoR-like regulator that represses expression of adjacent genes by binding specifically to a pair of canonical operator sites positioned in the NWMN_0027–0026.5 intergenic region. Inspection of these regulated genes suggests a role in assimilation of inorganic sulfur from thiosulfate and vectorial sulfur transfer, and we designate NWMN_0026.5 as CstR (CsoR-like sulfur transferase repressor). Expression analysis demonstrates that CsoR and CstR control their respective regulons in response to distinct stimuli with no overlap in vivo. Unlike CsoR, CstR does not form a stable complex with Cu(I); operator binding is instead inhibited by oxidation of the intersubunit cysteine pair to a mixture of disulfide and trisulfide linkages by a likely metabolite of thiosulfate assimilation, sulfite. CsoR is unreactive toward sulfite under the same conditions. We conclude that CsoR and CstR are paralogs in S. aureus that function in the same cytoplasm to control distinct physiological processes. PMID:21339296

Grossoehme, Nicholas; Kehl-Fie, Thomas E.; Ma, Zhen; Adams, Keith W.; Cowart, Darin M.; Scott, Robert A.; Skaar, Eric P.; Giedroc, David P.

2011-01-01

104

Flame Retardant Epoxy Resins  

NASA Technical Reports Server (NTRS)

As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.

2004-01-01

105

Fire-retardant foams  

NASA Technical Reports Server (NTRS)

Family of polyimide resins are being developed as foams with exceptional fire-retardant properties. Foams are potentially useful for seat cushions in aircraft and ground vehicles and for applications such as home furnishings and building-construction materials. Basic formulations can be modified with reinforcing fibers or fillers to produce celular materials for variety of applications. By selecting reactants, polymer structure can be modified to give foams with properties ranging from high resiliency and flexibility to brittleness and rigidity.

Gagliani, J.

1978-01-01

106

Identification and characterization of the rlp1+, the novel Rad51 paralog in the fission yeast Schizosaccharomyces pombe.  

PubMed

A new DNA repair gene from fission yeast Schizosaccharomyces pombe rlp1+ (RecA-like protein) has been identified. Rlp1 shows homology to RecA-like proteins, and is the third S. pombe Rad51 paralog besides Rhp55 and Rhp57. The new gene encodes a 363 aa protein with predicted Mr of 41,700 and has NTP-binding motif. The rlp1Delta mutant is sensitive to methyl methanesulfonate (MMS), ionizing radiation (IR), and camptothecin (CPT), although to a lesser extent than the deletion mutants of rhp55+ and rhp51+ genes. In contrast to other recombinational repair mutants, the rlp1Delta mutant does not exhibit sensitivity to UV light and mitomycin C (MMC). Mitotic recombination is moderately reduced in rlp1 mutant. Epistatic analysis of MMS and IR-sensitivity of rlp1Delta mutant indicates that rlp1+ acts in the recombinational pathway of double-strand break (DSB) repair together with rhp51+, rhp55+, and rad22+ genes. Yeast two-hybrid analysis suggests that Rlp1 may interact with Rhp57 protein. We propose that Rlp1 have an accessory role in repair of a subset of DNA damage induced by MMS and IR, and is required for the full extent of DNA recombination and cell survival under condition of a replication fork collapse. PMID:15336631

Khasanov, Fuat K; Salakhova, Albina F; Chepurnaja, Olga V; Korolev, Vladimir G; Bashkirov, Vladimir I

2004-10-01

107

MICU2, a Paralog of MICU1, Resides within the Mitochondrial Uniporter Complex to Regulate Calcium  

E-print Network

mitochondrial respiration or membrane potential. The results identify MICU2 as a new component of the uniporter mitochondrial membrane. Recently, we used comparative genomics to identify MICU1 and MCU as the key regulatoryMICU2, a Paralog of MICU1, Resides within the Mitochondrial Uniporter Complex to Regulate Calcium

Mootha, Vamsi K.

108

RAD51 paralogs promote homology-directed repair at diversifying immunoglobulin V regions  

Microsoft Academic Search

BACKGROUND: Gene conversion depends upon the same factors that carry out more general process of homologous recombination, including homologous gene targeting and recombinational repair. Among these are the RAD51 paralogs, conserved factors related to the key recombination factor, RAD51. In chicken and other fowl, gene conversion (templated mutation) diversifies immunoglobulin variable region sequences. This allows gene conversion and recombinational repair

Ellen C Ordinario; Munehisa Yabuki; Priya Handa; W. Jason Cummings; Nancy Maizels

2009-01-01

109

Sibling rivalry among paralogs promotes evolution of the human brain.  

PubMed

Geneticists have long sought to identify the genetic changes that made us human, but pinpointing the functionally relevant changes has been challenging. Two papers in this issue suggest that partial duplication of SRGAP2, producing an incomplete protein that antagonizes the original, contributed to human brain evolution. PMID:22579279

Tyler-Smith, Chris; Xue, Yali

2012-05-11

110

Toxic effects of two brominated flame retardants BDE-47 and BDE-183 on the survival and protein expression of the tubificid Monopylephorus limosus.  

PubMed

The toxic effects of two brominated diphenyl ethers (BDE), BDE-47, and BDE-183, on a benthic oligochaete tubificid, Monopylephorus limosus were studied under laboratory conditions. Investigated responses included survival, growth, and protein expression profiles, at BDE concentrations of 1, 10, 100, and 700 ng/g on a dry soil weight basis, with isooctane as the carrier solvent. Body weight losses among treatments were insignificant after 8 weeks of exposure. The 8-wk LC(50) of BDE-47 and -183 were 2311 and 169 ng/g, respectively. By applying multivariate analysis techniques, protein expression patterns were compared and correlated with stressful sources of long-term culture, carrier solvent, BDE-47 and -183. The treatment of 8-wk 100 ng/g BDE-47 was most closely clustered to the 10 ng/g BDE-183 treatment, based on the 40 examined protein spots. This indicated that BDE-183 was more potent to M. limosus, than was BDE-47. The 2-wk and 8-wk controls clustered into different groups indicating the occurrence of physiological changes due to long-term laboratory culture. Additionally, solvent effect was shown by grouping the isooctane carrier to different clusters. With further characterization by principle component analysis, it was found that the separation was mainly contributed by the 2nd principal-component. And, the primarily inhibitory variation was at spots 2 (UMP-CMP kinase) and 40 (plasma retinol-binding protein precursor) in the 8-wk groups. On the contrary, protein spots 16 (cell division control protein 2 homolog) and 24 (mitochondrial DNA mismatch repair protein) showed stimulatory variation. In all, the observed proteomic responses suggest that BDEs disrupted metabolic function in M. limosus and multivariate analysis tool offers significant potential for the assessment of various stress sources at biochemical level. PMID:22818847

Chiu, K H; Lin, C-R; Huang, H-W; Shiea, J; Liu, L L

2012-10-01

111

Ancient Origin of Chaperonin Gene Paralogs Involved in Ciliopathies  

PubMed Central

The Bardet-Biedl Syndrome (BBS) is a human developmental disorder that has been associated with fourteen BBS genes affecting the development of cilia. Three BBS genes are distant relatives of chaperonin proteins, a family of chaperones well known for the protein-folding role of their double-ringed complexes. Chaperonin-like BBS genes were originally thought to be vertebrate-specific, but related genes from different metazoan species have been identified as chaperonin-like BBS genes based on sequence similarity. Our phylogenetic analyses confirmed the classification of these genes in the chaperonin-like BBS gene family, and set the origin of the gene family earlier than the time of separation of Bilateria, Cnidaria, and Placozoa. By extensive searches of chaperonin-like genes in complete genomes representing several eukaryotic lineages, we discovered the presence of chaperonin-like BBS genes also in the genomes of Phytophthora and Pythium, belonging to the group of Oomycetes. This finding suggests that the chaperonin-like BBS gene family had already evolved before the origin of Metazoa, as early in eukaryote evolution as before separation of the lineages of Unikonts and Chromalveolates. The analysis of coding sequences indicated that chaperonin-like BBS proteins have evolved in all lineages under constraining selection. Furthermore, analysis of the predicted structural features suggested that, despite their high rate of divergence, chaperonin-like BBS proteins mostly conserve a typical chaperonin-like three-dimensional structure, but question their ability to assemble and function as chaperonin-like double-ringed complexes. PMID:24010126

Mukherjee, Krishanu; Brocchieri, Luciano

2013-01-01

112

Intrauterine growth retardation.  

PubMed

Intrauterine growth retardation (IUGR), which is defined as less than 10 percent of predicted fetal weight for gestational age, may result in significant fetal morbidity and mortality if not properly diagnosed. The condition is most commonly caused by inadequate maternal-fetal circulation, with a resultant decrease in fetal growth. Less common causes include intrauterine infections such as cytomegalovirus and rubella, and congenital anomalies such as trisomy 21 and trisomy 18. When IUGR is recognized, it is important to attempt to correct reversible causes, although many of the conditions responsible for IUGR are not amenable to antenatal therapy. Close fetal surveillance with delivery before 38 weeks of gestation is usually recommended. Some infants born with IUGR have cognitive and medical problems, although for most infants the long-term prognosis is good. PMID:9803202

Vandenbosche, R C; Kirchner, J T

1998-10-15

113

Robustness of Helicobacter pylori Infection Conferred by Context-Variable Redundancy among Cysteine-Rich Paralogs  

PubMed Central

Deletion of single genes from expanded gene families in bacterial genomes often does not elicit a phenotype thus implying redundancy or functional non-essentiality of paralogous genes. The molecular mechanisms that facilitate evolutionary maintenance of such paralogs despite selective pressures against redundancy remain mostly unexplored. Here, we investigate the evolutionary, genetic, and functional interaction between the Helicobacter pylori cysteine-rich paralogs hcpG and hcpC in the context of H. pylori infection of cultured mammalian cells. We find that in natural H. pylori populations both hcpG and hcpC are maintained by positive selection in a dual genetic relationship that switches from complete redundancy during early infection, whereby ?hcpC or ?hcpG mutants themselves show no growth defect but a significant growth defect is seen in the ?hcpC,?hcpG double mutant, to quantitative redundancy during late infection wherein the growth defect of the ?hcpC mutant is exacerbated in the ?hcpC,?hcpG double mutant although the ?hcpG mutant itself shows no defect. Moreover, during early infection both hcpG and hcpC are essential for optimal translocation of the H. pylori HspB/GroEL chaperone, but during middle-to-late infection hcpC alone is necessary and sufficient for HspB/GroEL translocation thereby revealing the lack of functional compensation among paralogs. We propose that evolution of context-dependent differences in the nature of genetic redundancy, and function, between hcpG and hcpC may facilitate their maintenance in H. pylori genomes, and confer robustness to H. pylori growth during infection of cultured mammalian cells. PMID:23555707

Putty, Kalyani; Marcus, Sarah A.; Mittl, Peer R. E.; Bogadi, Lindsey E.; Hunter, Allison M.; Arur, Swathi; Berg, Douglas E.; Sethu, Palaniappan; Kalia, Awdhesh

2013-01-01

114

Avoiding paralogy: diploid loci for allotetraploid blue sucker fish ( Cycleptus elongatus , Catostomidae)  

Microsoft Academic Search

The blue sucker (Cycleptus elongatus) is a widespread North American catostomid fish that appears to be declining throughout much of its range. Here, we describe\\u000a the isolation and characterization of eleven microsatellite loci developed for population genetic studies in the genus. We\\u000a show that an additional step of cloning and sequencing can be useful in isolating paralogous loci that often

Michael L. Bessert; Craig Sitzman; Guillermo Ortí

2007-01-01

115

Two Rac paralogs regulate polarized growth in the human fungal pathogen Cryptococcus neoformans.  

PubMed

A genome wide analysis of the human fungal pathogen Cryptococcus neoformans var. grubii has revealed a number of duplications of highly conserved genes involved in morphogenesis. Previously, we reported that duplicate Cdc42 paralogs provide C. neoformans with niche-specific responses to environmental stresses: Cdc42 is required for thermotolerance, while Cdc420 supports the formation of titan cells. The related Rho-GTPase Rac1 has been shown in C. neoformans var. neoformans to play a major role in filamentation and to share Cdc42/Cdc420 binding partners. Here we report the characterization of a second Rac paralog in C. neoformans, Rac2, and describe its overlapping function with the previously described CnRac, Rac1. Further, we demonstrate that the Rac paralogs play a primary role in polarized growth via the organization of reactive oxygen species and play only a minor role in the organization of actin. Finally, we provide preliminary evidence that pharmacological inhibitors of Rac activity and actin stability have synergistic activity. PMID:23748012

Ballou, Elizabeth Ripley; Selvig, Kyla; Narloch, Jessica L; Nichols, Connie B; Alspaugh, J Andrew

2013-08-01

116

Protein C activator from the venom of Agkistrodon blomhoffi ussuriensis retards thrombus formation in the arterio-venous shunt in rats.  

PubMed

Protein C (PC) is an anticoagulant protein which, being activated by thrombin, degrades factors V/Va and VIII/VIIIa and releases a tissue-type plasminogen activator. Some Agkistrodon snake venoms contain PC activators which, in experiments, exert an anticoagulant action. An antithrombotic effect of the PC activator from the venom of A. blomhoffi ussuriensis on the model of thrombus formation in the arterio-venous shunt in rats was under investigation. Administration of the PC activator resulted in a dose-dependent prolongation of the thrombus formation time and a decrease in plasma PC activity, which were accompanied by a decrease in factor V activity and APTT prolongation. No reliable changes in the t-PA level, ADP- and epinephrine-induced platelet aggregation were observed. Platelet adhesion to glass beads diminished. We assume that the antithrombotic effect of the PC activator from the A. blomhoffi venom in the platelet-dependent thrombosis model is caused by PC activation and subsequent factor V inactivation as well as by platelet adhesiveness reduction. PMID:8378894

Kogan, A E; Bashkov, G V; Bobruskin, I D; Romanova, E P; Makarov, V A; Strukova, S M

1993-06-01

117

Adenovirus Regulates Sumoylation of Mre11-Rad50-Nbs1 Components through a Paralog-Specific Mechanism  

PubMed Central

The Mre11-Rad50-Nbs1 (MRN) complex plays a key role in the DNA damage response, presenting challenges for DNA viruses and retroviruses. To inactivate this complex, adenovirus (Ad) makes use of the E1B-55K and E4-open reading frame 6 (ORF6) proteins for ubiquitin (Ub)-mediated, proteasome-dependent degradation of MRN and the E4-ORF3 protein for relocalization and sequestration of MRN within infected-cell nuclei. Here, we report that Mre11 is modified by the Ub-related modifier SUMO-2 and Nbs1 is modified by both SUMO-1 and SUMO-2. We found that Mre11 and Nbs1 are sumoylated during Ad5 infection and that the E4-ORF3 protein is necessary and sufficient to induce SUMO conjugation. Relocalization of Mre11 and Nbs1 into E4-ORF3 nuclear tracks is required for this modification to occur. E4-ORF3-mediated SUMO-1 conjugation to Nbs1 and SUMO-2 conjugation to Mre11 and Nbs1 are transient during wild-type Ad type 5 (Ad5) infection. In contrast, SUMO-1 conjugation to Nbs1 is stable in cells infected with E1B-55K or E4-ORF6 mutant viruses, suggesting that Ad regulates paralog-specific desumoylation of Nbs1. Inhibition of viral DNA replication blocks deconjugation of SUMO-2 from Mre11 and Nbs1, indicating that a late-phase process is involved in Mre11 and Nbs1 desumoylation. Our results provide direct evidence of Mre11 and Nbs1 sumoylation induced by the Ad5 E4-ORF3 protein and an important example showing that modification of a single substrate by both SUMO-1 and SUMO-2 is regulated through distinct mechanisms. Our findings suggest how E4-ORF3-mediated relocalization of the MRN complex influences the cellular DNA damage response. PMID:22740413

Sohn, Sook-Young

2012-01-01

118

Human 14-3-3 Paralogs Differences Uncovered by Cross-Talk of Phosphorylation and Lysine Acetylation  

PubMed Central

The 14-3-3 protein family interacts with more than 700 different proteins in mammals, in part as a result of its specific phospho-serine/phospho-threonine binding activity. Upon binding to 14-3-3, the stability, subcellular localization and/or catalytic activity of the ligands are modified. Seven paralogs are strictly conserved in mammalian species. Although initially thought as redundant, the number of studies showing specialization is growing. We created a protein-protein interaction network for 14-3-3, kinases and their substrates signaling in human cells. We included information of phosphorylation, acetylation and other PTM sites, obtaining a complete representation of the 14-3-3 binding partners and their modifications. Using a computational system approach we found that networks of each 14-3-3 isoform are statistically different. It was remarkable to find that Tyr was the most phosphorylatable amino acid in domains of 14-3-3 epsilon partners. This, together with the over-representation of SH3 and Tyr_Kinase domains, suggest that epsilon could be involved in growth factors receptors signaling pathways particularly. We also found that within zeta’s network, the number of acetylated partners (and the number of modify lysines) is significantly higher compared with each of the other isoforms. Our results imply previously unreported hidden differences of the 14-3-3 isoforms interaction networks. The phosphoproteome and lysine acetylome within each network revealed post-transcriptional regulation intertwining phosphorylation and lysine acetylation. A global understanding of these networks will contribute to predict what could occur when regulatory circuits become dysfunctional or are modified in response to external stimuli. PMID:23418452

Uhart, Marina; Bustos, Diego M.

2013-01-01

119

Neurotoxicity of brominated flame retardants  

EPA Science Inventory

Polybrominated diphenyl ethers (PBDEs) have been commonly used as commercial flame retardants in a variety of products including plastics and textiles. Despite their decreasing usage worldwide, congeners continue to accumulate in the environment, including soil, dust, food, anima...

120

Can earthworms survive fire retardants?  

USGS Publications Warehouse

Most common fire retardants are foams or are similar to common agricultural fertilizers, such as ammonium sulfate and ammonium phosphate. Although fire retardants are widely applied to soils, we lack basic information about their toxicities to soil organisms. We measured the toxicity of five fire retardants (Firetrol LCG-R, Firetrol GTS-R, Silv-Ex Foam Concentrate, Phos-chek D-75, and Phos-chek WD-881) to earthworms using the pesticide toxicity test developed for earthworms by the European Economic Community. None was lethal at 1,000 ppm in the soil, which was suggested as a relatively high exposure under normal applications. We concluded that the fire retardants tested are relatively nontoxic to soil organisms compared with other environmental chemicals and that they probably do not reduce earthworm populations when applied under usual firefighting conditions.

Beyer, W.N.; Olson, A.

1996-01-01

121

INTRODUCTION TO BROMINATED FLAME RETARDANTS  

EPA Science Inventory

Brominated flame retardants (BFRs) are a large and diverse class of major industrial products used to provide fire safety. Tetrabromobisphenol A (TBBPA), Hexabromocylocodecane (HBCD), and Polybrominated Diphenyl Ethers (PBDEs) are the major commercial compounds. TBBPA is a react...

122

Attentional Habituation and Mental Retardation  

Microsoft Academic Search

A theoretical proposal is offered concerning individual differences in cognitive processes. The focus is on mental retardation and the comparative problem-solving performance of ‘normal’ and ‘retarded’ children. On the basis of Jeffrey’s analysis of attention and cognitive development, it is proposed that IQ and MA differences in problem-solving behavior reflect differences in (a) speed of OR habituation and (b) ability

Lita Furby

1974-01-01

123

Epigenetic Mechanisms of Mental Retardation  

Microsoft Academic Search

\\u000a Mental retardation is a common form of cognitive impairment affecting ~3% of the population in industrialized countries. The\\u000a mental retardation syndrome incorporates a highly diverse group of mental disorders characterized by the combination of cognitive\\u000a impairment and defective adaptive behavior. The genetic basis of the disease is strongly supported by identification of the\\u000a genetic lesions associated with impaired cognition, learning,

Anne Schaefer; Alexander Tarakhovsky; Paul Greengard

124

Independent evolutionary origin of fem paralogous genes and complementary sex determination in hymenopteran insects.  

PubMed

The primary signal of sex determination in the honeybee, the complementary sex determiner (csd) gene, evolved from a gene duplication event from an ancestral copy of the fem gene. Recently, other paralogs of the fem gene have been identified in several ant and bumblebee genomes. This discovery and the close phylogenetic relationship of the paralogous gene sequences led to the hypothesis of a single ancestry of the csd genetic system of complementary sex determination in the Hymenopteran insects, in which the fem and csd gene copies evolved as a unit in concert with the mutual transfers of sequences (concerted evolution). Here, we show that the paralogous gene copies evolved repeatedly through independent gene duplication events in the honeybee, bumblebee, and ant lineage. We detected no sequence tracts that would indicate a DNA transfer between the fem and the fem1/csd genes between different ant and bee species. Instead, we found tracts of duplication events in other genomic locations, suggesting that gene duplication was a frequent event in the evolution of these genes. These and other evidences suggest that the fem1/csd gene originated repeatedly through gene duplications in the bumblebee, honeybee, and ant lineages in the last 100 million years. Signatures of concerted evolution were not detectable, implicating that the gene tree based on neutral synonymous sites represents the phylogenetic relationships and origins of the fem and fem1/csd genes. Our results further imply that the fem1 and csd gene in bumblebees, honeybees, and ants are not orthologs, because they originated independently from the fem gene. Hence, the widely shared and conserved complementary sex determination mechanism in Hymenopteran insects is controlled by different genes and molecular processes. These findings highlight the limits of comparative genomics and emphasize the requirement to study gene functions in different species and major hymenopteran lineages. PMID:24743790

Koch, Vasco; Nissen, Inga; Schmitt, Björn D; Beye, Martin

2014-01-01

125

Independent Evolutionary Origin of fem Paralogous Genes and Complementary Sex Determination in Hymenopteran Insects  

PubMed Central

The primary signal of sex determination in the honeybee, the complementary sex determiner (csd) gene, evolved from a gene duplication event from an ancestral copy of the fem gene. Recently, other paralogs of the fem gene have been identified in several ant and bumblebee genomes. This discovery and the close phylogenetic relationship of the paralogous gene sequences led to the hypothesis of a single ancestry of the csd genetic system of complementary sex determination in the Hymenopteran insects, in which the fem and csd gene copies evolved as a unit in concert with the mutual transfers of sequences (concerted evolution). Here, we show that the paralogous gene copies evolved repeatedly through independent gene duplication events in the honeybee, bumblebee, and ant lineage. We detected no sequence tracts that would indicate a DNA transfer between the fem and the fem1/csd genes between different ant and bee species. Instead, we found tracts of duplication events in other genomic locations, suggesting that gene duplication was a frequent event in the evolution of these genes. These and other evidences suggest that the fem1/csd gene originated repeatedly through gene duplications in the bumblebee, honeybee, and ant lineages in the last 100 million years. Signatures of concerted evolution were not detectable, implicating that the gene tree based on neutral synonymous sites represents the phylogenetic relationships and origins of the fem and fem1/csd genes. Our results further imply that the fem1 and csd gene in bumblebees, honeybees, and ants are not orthologs, because they originated independently from the fem gene. Hence, the widely shared and conserved complementary sex determination mechanism in Hymenopteran insects is controlled by different genes and molecular processes. These findings highlight the limits of comparative genomics and emphasize the requirement to study gene functions in different species and major hymenopteran lineages. PMID:24743790

Koch, Vasco; Nissen, Inga; Schmitt, Bjorn D.; Beye, Martin

2014-01-01

126

Development of novel fire retardants  

NASA Astrophysics Data System (ADS)

Numerous candidate environmentally-friendly, water-soluble, and non-toxic fire retardants and fire-retarding processes were developed and tested according to the ASTM D 3801 flammability test and the NRL 8093 smoldering test. Flame retardants that passed the ASTM D 3801 flammability test with the highest V0 rating were boron esters of guanidinium hydroxycarboxylate (glycolate, salicylate and dihydroxybenzoate), zinc gluconate borate ester, and cyanoacetate salts of organic bases (melaminium, cyanoguanidinium, and ammonium). Several related compounds pass this test with the lower V1 rating. Two new synergistic flame and smolder retarding systems were developed in which the individual components were incapable of preventing flame spread or smoldering but in combination they were highly effective. These systems were mixtures of either guanyl urea phosphate and boric acid or beta-alanine and boric acid. Compositions leading to the maximum solubility of boron oxides in the ammonium borate/sodium borate system were determined at several temperatures and the formation of mixtures exceeding 50% dissolved boric acid equivalents was found possible. These mixtures were applied as flame retardants for wood, paper, and carbon-loaded polyurethane foam both directly and indirectly by in situ precipitation of boric acid or zinc borate by appropriate chemical treatments. These all passed the ASTM flammability test with V0 rating. The performance of the boron-containing fire retardants is likely due to deposition of protective boron oxide coatings at elevated temperatures except where phosphate was present and a protective boron phosphate was deposited instead. In all cases, the oxidation of carbonaceous char was strongly inhibited. The hydroxycarboxylate groups generally formed intumescent chars during thermal decomposition that also contributed to fire retardancy.

Sigdel Regmi, Bhawani

127

A single allele of Hdac2 but not Hdac1 is sufficient for normal mouse brain development in the absence of its paralog.  

PubMed

The histone deacetylases HDAC1 and HDAC2 are crucial regulators of chromatin structure and gene expression, thereby controlling important developmental processes. In the mouse brain, HDAC1 and HDAC2 exhibit different developmental stage- and lineage-specific expression patterns. To examine the individual contribution of these deacetylases during brain development, we deleted different combinations of Hdac1 and Hdac2 alleles in neural cells. Ablation of Hdac1 or Hdac2 by Nestin-Cre had no obvious consequences on brain development and architecture owing to compensation by the paralog. By contrast, combined deletion of Hdac1 and Hdac2 resulted in impaired chromatin structure, DNA damage, apoptosis and embryonic lethality. To dissect the individual roles of HDAC1 and HDAC2, we expressed single alleles of either Hdac1 or Hdac2 in the absence of the respective paralog in neural cells. The DNA-damage phenotype observed in double knockout brains was prevented by expression of a single allele of either Hdac1 or Hdac2. Strikingly, Hdac1(-/-)Hdac2(+/-) brains showed normal development and no obvious phenotype, whereas Hdac1(+/-)Hdac2(-/-) mice displayed impaired brain development and perinatal lethality. Hdac1(+/-)Hdac2(-/-) neural precursor cells showed reduced proliferation and premature differentiation mediated by overexpression of protein kinase C, delta, which is a direct target of HDAC2. Importantly, chemical inhibition or knockdown of protein kinase C delta was sufficient to rescue the phenotype of neural progenitor cells in vitro. Our data indicate that HDAC1 and HDAC2 have a common function in maintaining proper chromatin structures and show that HDAC2 has a unique role by controlling the fate of neural progenitors during normal brain development. PMID:24449838

Hagelkruys, Astrid; Lagger, Sabine; Krahmer, Julia; Leopoldi, Alexandra; Artaker, Matthias; Pusch, Oliver; Zezula, Jürgen; Weissmann, Simon; Xie, Yunli; Schöfer, Christian; Schlederer, Michaela; Brosch, Gerald; Matthias, Patrick; Selfridge, Jim; Lassmann, Hans; Knoblich, Jürgen A; Seiser, Christian

2014-02-01

128

Impairment of fragile X mental retardation protein-metabotropic glutamate receptor 5 signaling and its downstream cognates ras-related C3 botulinum toxin substrate 1, amyloid beta A4 precursor protein, striatal-enriched protein tyrosine phosphatase, and homer 1, in autism: a postmortem study in cerebellar vermis and superior frontal cortex  

PubMed Central

Background Candidate genes associated with idiopathic forms of autism overlap with other disorders including fragile X syndrome. Our laboratory has previously shown reduction in fragile X mental retardation protein (FMRP) and increase in metabotropic glutamate receptor 5 (mGluR5) in cerebellar vermis and superior frontal cortex (BA9) of individuals with autism. Methods In the current study we have investigated expression of four targets of FMRP and mGluR5 signaling - homer 1, amyloid beta A4 precursor protein (APP), ras-related C3 botulinum toxin substrate 1 (RAC1), and striatal-enriched protein tyrosine phosphatase (STEP) - in the cerebellar vermis and superior frontal cortex (BA9) via SDS-PAGE and western blotting. Data were analyzed based on stratification with respect to age (children and adolescents vs. adults), anatomic region of the brain (BA9 vs. cerebellar vermis), and impact of medications (children and adolescents on medications (n = 4) vs. total children and adolescents (n = 12); adults on medications (n = 6) vs. total adults (n = 12)). Results There were significant increases in RAC1, APP 120 kDa and APP 80 kDa proteins in BA9 of children with autism vs. healthy controls. None of the same proteins were significantly affected in cerebellar vermis of children with autism. In BA9 of adults with autism there were significant increases in RAC1 and STEP 46 kDa and a significant decrease in homer 1 vs. controls. In the vermis of adult subjects with autism, RAC1 was significantly increased while APP 120, STEP 66 kDa, STEP 27 kDa, and homer 1 were significantly decreased when compared with healthy controls. No changes were observed in vermis of children with autism. There was a significant effect of anticonvulsant use on STEP 46 kDa/?-actin and a potential effect on homer 1/NSE, in BA9 of adults with autism. However, no other significant confound effects were observed in this study. Conclusions Our findings provide further evidence of abnormalities in FMRP and mGluR5 signaling partners in brains of individuals with autism and open the door to potential targeted treatments which could help ameliorate the symptoms of autism. PMID:23803181

2013-01-01

129

Human DNA helicase HELQ participates in DNA interstrand crosslink tolerance with ATR and RAD51 paralogs  

PubMed Central

Mammalian HELQ is a 3?–5? DNA helicase with strand displacement activity. Here we show that HELQ participates in a pathway of resistance to DNA interstrand crosslinks (ICLs). Genetic disruption of HELQ in human cells enhances cellular sensitivity and chromosome radial formation by the ICL-inducing agent mitomycin C (MMC). A significant fraction of MMC sensitivity is independent of the Fanconi anaemia pathway. Sister chromatid exchange frequency and sensitivity to UV radiation or topoisomerase inhibitors is unaltered. Proteomic analysis reveals that HELQ is associated with the RAD51 paralogs RAD51B/C/D and XRCC2, and with the DNA damage-responsive kinase ATR. After treatment with MMC, reduced phosphorylation of the ATR substrate CHK1 occurs in HELQ-knockout cells, and accumulation of G2/M cells is reduced. The results indicate that HELQ operates in an arm of DNA repair and signalling in response to ICL. Further, the association with RAD51 paralogs suggests HELQ as a candidate ovarian cancer gene. PMID:24005565

Takata, Kei-ichi; Reh, Shelley; Tomida, Junya; Person, Maria D.; Wood, Richard D.

2013-01-01

130

Recurrence risks in mental retardation.  

PubMed Central

Despite improvements in diagnostic techniques and progress made in mapping genes associated with syndromal mental handicap, the estimation of recurrence risks in non-syndromal mental retardation is still dependent on empirical data. Unfortunately, few studies are available to guide the clinician and their results differ significantly. For example, recurrence risks to all sibs of a male index patient with severe mental retardation vary between 3.5% and 14% in commonly quoted series. The present review highlights the problems involved in interpreting the previous work in this area and discusses the definition of mental retardation according to the degree of severity, phenotype, and its pattern of inheritance. In planning future studies, an appreciation of these issues should allow us to derive accurate and comparable risk figures for use in counselling affected subjects and their families. PMID:9541099

Crow, Y J; Tolmie, J L

1998-01-01

131

Auto cannibalism in mental retardation  

PubMed Central

Mental retardation (MR) deems an individual more vulnerable to psychopathologies. The individual may develop an array of behavioral disturbances manifesting themselves in the form of aggressive and destructive conduct, violent fits of anger, stereotyped, or self-injuring behavior. Self-injurious behavior is heterogeneous in nature ranging from mild to severe variant. We report a case of a 7-year-old boy with MR with self-inflicted severe oral injuries of cannibalistic nature presenting as cleft lip and palate. A more extensive research is needed on the problem behaviors in mentally retarded patients for early detection and effective and timely intervention leading to a better outcome. PMID:24891909

Verma, Rohit; Mina, Shaily; Sachdeva, Ankur

2014-01-01

132

Staufen2 functions in Staufen1-mediated mRNA decay by binding to itself and its paralog and promoting UPF1 helicase but not ATPase activity  

PubMed Central

Staufen (STAU)1-mediated mRNA decay (SMD) is a posttranscriptional regulatory mechanism in mammals that degrades mRNAs harboring a STAU1-binding site (SBS) in their 3?-untranslated regions (3? UTRs). We show that SMD involves not only STAU1 but also its paralog STAU2. STAU2, like STAU1, is a double-stranded RNA-binding protein that interacts directly with the ATP-dependent RNA helicase up-frameshift 1 (UPF1) to reduce the half-life of SMD targets that form an SBS by either intramolecular or intermolecular base-pairing. Compared with STAU1, STAU2 binds ?10-fold more UPF1 and ?two- to fivefold more of those SBS-containing mRNAs that were tested, and it comparably promotes UPF1 helicase activity, which is critical for SMD. STAU1- or STAU2-mediated augmentation of UPF1 helicase activity is not accompanied by enhanced ATP hydrolysis but does depend on ATP binding and a basal level of UPF1 ATPase activity. Studies of STAU2 demonstrate it changes the conformation of RNA-bound UPF1. These findings, and evidence for STAU1?STAU1, STAU2?STAU2, and STAU1?STAU2 formation in vitro and in cells, are consistent with results from tethering assays: the decrease in mRNA abundance brought about by tethering siRNA-resistant STAU2 or STAU1 to an mRNA 3? UTR is inhibited by downregulating the abundance of cellular STAU2, STAU1, or UPF1. It follows that the efficiency of SMD in different cell types reflects the cumulative abundance of STAU1 and STAU2. We propose that STAU paralogs contribute to SMD by “greasing the wheels” of RNA-bound UPF1 so as to enhance its unwinding capacity per molecule of ATP hydrolyzed. PMID:23263869

Park, Eonyoung; Gleghorn, Michael L.; Maquat, Lynne E.

2013-01-01

133

HANDBOOK OF MENTAL RETARDATION SYNDROMES.  

ERIC Educational Resources Information Center

THE CLINICAL SYNDROMES WHICH CONTRIBUTE TO THE PRODUCTION OF MENTAL RETARDATION ARE DESCRIBED BY SIGNS, SYMPTOMS, AND ETIOLOGY. SYNDROMES TREATED ARE (1) PRENATAL AND POSTNATAL INFECTIONS, (2) PRENATAL INTOXICATION AND ALLERGIC REACTIONS, (3) PRENATAL TRAUMA, PHYSICAL AGENTS, OR INTOXICATION, (4) BIRTH INJURIES, (5) POSTNATAL POISONS AND ALLERGIC…

CARTER, CHARLES H.

134

Engine retarding method and apparatus  

Microsoft Academic Search

A process is described for compression release retarding of a cycling multi-cylinder four cycle internal combustion engine having a crankshaft and an engine piston operatively connected to the crankshaft for each cylinder thereof and having intake and exhaust valves for each cylinder thereof comprising, for at least one cylinder thereof, the steps of reducing the flow of fuel to the

Meistrick

1986-01-01

135

Fire-retardant epoxy polymers  

NASA Technical Reports Server (NTRS)

Phosphorus atoms in molecular structure of epoxies make them fire-retardant without degrading their adhesive strength. Moreover, polymers are transparent, unlike compounds that contain arsenic or other inorganics. They have been used to bond polyvinylfluoride and polyether sulfone films onto polyimide glass laminates.

Akawie, R. I.; Bilow, N.; Giants, T. W.

1978-01-01

136

Psychotherapy With the Institutionalized Retarded  

Microsoft Academic Search

The belief that psychotherapy may be of value with the mentally retarded is of fairly recent origin. One has only to peruse the literature of the last several decades to find much skepticism as regards its worth in the area of mental deficiency. To mention just a few, Huttcfl (1945), Healy and Bronner ( 1939) , Morgan ( 1926), Paster

IRA GOLDBERG

137

MEDICAL ASPECTS OF MENTAL RETARDATION.  

ERIC Educational Resources Information Center

TO AID PHYSICIANS AND OTHER SPECIALISTS IN DIAGNOSING CASES OF MENTAL RETARDATION AND IN COUNSELING PARENTS, THE BOOK PRESENTS MEDICAL INFORMATION, INCLUDING RECENT ADVANCES. THIRTY-TWO AUTHORITIES CONTRIBUTE CHAPTERS IN SUCH AREAS AS DIAGNOSIS, METABOLISM, NUTRITION, ETIOLOGY, MONGOLISM, CRANIAL ABNORMALITIES, BIRTH INJURIES, INFECTIONS,…

CARTER, CHARLES H., COMP.

138

Group Counseling with Retarded Offenders.  

ERIC Educational Resources Information Center

Describes a group counseling program that helps retarded inmates develop problem solving skills and learn to use existing resources in their own behalf. An outcome study of 46 inmates indicated combined group and individual counseling was more effective than individual counseling alone. (JAC)

Steiner, Joseph

1984-01-01

139

[Sterilization of mentally retarded girls].  

PubMed

About 1000 sterilizations are performed in mentally retarded women in Germany every year out of about 30,000-50,000 operations. Considering that 10 out of 1000 people are mentally retarded, they are overrepresented in this procedure. There are no clear regulations concerning their sterilization because of the historical antecedents of abuse of the rights of the mentally retarded. A 1933 law about hereditary health resulted in the forced sterilization of 300,000-400,000 persons mostly based on ideological indications. During the 1972 reform of the penal code the attempt to regulate sterilization with abortion and set very stringent conditions for minors and competent persons did not succeed. In 1987 federal medical association guidelines and the Einbecker recommendations were published permitting sterilization if it was in the well-meant interest of the mentally retarded person and the indications analogous to abortion could be considered. The consent of legal representative, guardian, and possibly both parents had to be secured, and the guardian court had to be given prior notice. The patient had to be advised and without her consent the operation could not be carried out. A draft proposal to become law in 1992 would forbid sterilization of minors: the consent of the guardian court is needed for incompetents of age if pregnancy would likely result without sterilization and it could not be prevented by other means. The handicapped oppose the sterilization of mentally retarded and the use of genetical criteria laid down in the regulation for indications for legal abortion. In 1990 the federal parliament passed the law on the rights of guardianship and care for those of age forbidding forced sterilization and sterilization of minors. This legislation will give clear guidelines for doctors. Some legal uncertainties still exist that can be used responsibly for the interest of the patient. PMID:1743571

Lenard, H G; Müller, K

1991-04-01

140

The RAB Family GTPase Rab1A from Plasmodium falciparum Defines a Unique Paralog Shared by Chromalveolates and Rhizaria  

E-print Network

The RAB Family GTPase Rab1A from Plasmodium falciparum Defines a Unique Paralog Shared, Canada V6T 1Z4 ABSTRACT. The RAB GTPases, which are involved in regulation of endomembrane trafficking, exhibit a complex but incompletely understood evolutionary history. We elucidated the evolution of the RAB

Keeling, Patrick

141

Gene Conversion and DNA Sequence Polymorphism in the Sex-Determination Gene fog-2 and Its Paralog ftr-1  

E-print Network

Gene Conversion and DNA Sequence Polymorphism in the Sex-Determination Gene fog-2 and Its Paralog to duplication events. fog-2, a sex-determination gene unique to Caenorhabditis elegans and implicated of unknown function. Synonymous sequence divergence in regions of fog-2 and ftr-1 (excluding recent gene

Bergthorsson, Ulfar

142

Physiology, pharmacology, and therapeutic relevance of urocortins in mammals: ancient CRF paralogs.  

PubMed

Urocortins, three paralogs of the stress-related peptide corticotropin-releasing factor (CRF) found in bony fish, amphibians, birds, and mammals, have unique phylogenies, pharmacologies, and tissue distributions. As a result and despite a structural family resemblance, the natural functions of urocortins and CRF in mammalian homeostatic responses differ substantially. Endogenous urocortins are neither simply counterpoints nor mimics of endogenous CRF action. In their own right, urocortins may be clinically relevant molecules in the pathogenesis or management of many conditions, including congestive heart failure, hypertension, gastrointestinal and inflammatory disorders (irritable bowel syndrome, active gastritis, gastroparesis, and rheumatoid arthritis), atopic/allergic disorders (dermatitis, urticaria, and asthma), pregnancy and parturition (preeclampsia, spontaneous abortion, onset, and maintenance of effective labor), major depression and obesity. Safety trials for intravenous urocortin treatment have already begun for the treatment of congestive heart failure. Further understanding the unique functions of urocortin 1, urocortin 2, and urocortin 3 action may uncover other therapeutic opportunities. PMID:17083971

Fekete, Eva M; Zorrilla, Eric P

2007-04-01

143

Partial functional redundancy between Hoxa5 and Hoxb5 paralog genes during lung morphogenesis  

PubMed Central

Hox genes encode transcription factors governing complex developmental processes in several organs. A subset of Hox genes are expressed in the developing lung. Except for Hoxa5, the lack of overt lung phenotype in single mutants suggests that Hox genes may not play a predominant role in lung ontogeny or that functional redundancy may mask anomalies. In the Hox5 paralog group, both Hoxa5 and Hoxb5 genes are expressed in the lung mesenchyme whereas Hoxa5 is also expressed in the tracheal mesenchyme. Herein, we generated Hoxa5;Hoxb5 compound mutant mice to evaluate the relative contribution of each gene to lung development. Hoxa5;Hoxb5 mutants carrying the four mutated alleles displayed an aggravated lung phenotype, resulting in the death of the mutant pups at birth. Characterization of the phenotype highlighted the role of Hoxb5 in lung formation, the latter being involved in branching morphogenesis, goblet cell specification, and postnatal air space structure, revealing partial functional redundancy with Hoxa5. However, the Hoxb5 lung phenotypes were less severe than those seen in Hoxa5 mutants, likely because of Hoxa5 compensation. New specific roles for Hoxa5 were also unveiled, demonstrating the extensive contribution of Hoxa5 to the developing respiratory system. The exclusive expression of Hoxa5 in the trachea and the phrenic motor column likely underlies the Hoxa5-specific trachea and diaphragm phenotypes. Altogether, our observations establish that the Hoxa5 and Hoxb5 paralog genes shared some functions during lung morphogenesis, Hoxa5 playing a predominant role. PMID:23585229

Boucherat, Olivier; Montaron, Severine; Berube-Simard, Felix-Antoine; Aubin, Josee; Philippidou, Polyxeni; Wellik, Deneen M.; Dasen, Jeremy S.

2013-01-01

144

People with Mental Retardation Are Dying, Legally.  

ERIC Educational Resources Information Center

Criticizes the institution of the death penalty for convicted criminals with mental retardation. Examples are given of cases in which juries were not told of the defendant's mental retardation before sentencing, and a list of defendants with mental retardation that have been executed since 1976 is provided. (CR)

Keyes, Denis; And Others

1997-01-01

145

Low Elevated Lead Levels and Mental Retardation.  

ERIC Educational Resources Information Center

The relationship between low elevated lead absorption and mild mental retardation was investigated in 40 rural children (preschool to grade 12) without demonstrable cause for their retardation. Trace mineral analysis of hair samples from Ss and a control group (N=20) indicated the mean hair lead concentrations for the retarded Ss were considerably…

Marlowe, Mike; And Others

146

MOTOR CHARACTERISTICS OF THE MENTALLY RETARDED.  

ERIC Educational Resources Information Center

SCIENTIFIC DATA WERE OBTAINED ON THE MOTOR LEVELS OF ATTAINMENT AND/OR POTENTIALS OF THE MENTALLY RETARDED TO PROVIDE SCIENTIFIC BASES UPON WHICH TEACHERS MIGHT PREPARE FOR FUTURE RESPONSIBILITIES WITH MENTALLY RETARDED PERSONS. THE MAJOR OBJECTIVE WAS TO DETERMINE THE MOTOR CHARACTERISTICS OF THE MENTALLY RETARDED (IQ'S BELOW 80). THE MENTALLY…

FRANCIS, ROBERT J.; RARICK, LAWRENCE G.

147

International Review of Research in Mental Retardation.  

ERIC Educational Resources Information Center

The text of Volume 4 represents an international review of research in mental retardation dealing primarily with human and animal laboratory behavior. The contents range through the following topics: memory processes in retardates and normals by Norman Ellis; a theory of primary and secondary familial mental retardation by Arthur Jensen;…

Ellis, Norman R., Ed.

148

The theory of retarded potentials  

SciTech Connect

The theory of retarded potentials is formulated in a very general fashion which includes all postulates on the velocity of light, all definitions of the scalar and vector potentials and all forms of the force equation which have so far been mathematically formulated. Two of the four Maxwell equations are the same for all postulates; two may have slightly different forms. If the force field is studied directly, the four Maxwell equations are replaced by two equations which depend on the postulates employed.

Mirchandaney, A.S. (Cornell Univ., Ithaca, NY (USA)); Spencer, D.E.; Uma, S.Y.; Mann, P.J. (Univ. of Connecticut, Storrs (USA))

1988-09-01

149

Engine retarding method and apparatus  

SciTech Connect

A process is described for compression release retarding of a cycling multi-cylinder four cycle internal combustion engine having a crankshaft and an engine piston operatively connected to the crankshaft for each cylinder thereof and having intake and exhaust valves for each cylinder thereof comprising, for at least one cylinder thereof, the steps of reducing the flow of fuel to the cylinder, commencing opening the exhaust valve for the cylinder prior to the top dead center position of the engine piston during an upstroke of the piston corresponding to its compression stroke during normal operation of the engine to produce a compression release event, holding the exhaust valve open during a substantial portion of the ensuing downstroke of the engine piston, disabling the exhaust valve from moving at the point it would move in the cycle during normal operation of the engine, at least partially closing the exhaust valve commencing near to the bottom dead center position of the engine piston corresponding to its expansion stroke during normal operation of the engine, holding the exhaust valve in the partially closed position during at least the ensuing upstroke of the engine piston corresponding to its exhaust stroke during normal operation of the engine to produce a bleeder retarding event, operating the intake valve as it would move in the cycle during normal operation of the engine, and fully closing the exhaust valve commencing at least early during the ensuing downstroke of the engine piston corresponding to its intake stroke during normal operation of the engine whereby one compression release retarding event and one bleeder retarding event is produced in the one cylinder during each engine cycle comprising two revolutions of the crankshaft.

Meistrick, Z.S.

1986-06-03

150

Fire-Retardant Polymeric Additives  

NASA Technical Reports Server (NTRS)

Polyhydroxyamide (PHA) and polymethoxyamide (PMeOA) are fire-retardant (FR) thermoplastic polymers and have been found to be useful as an additive for imparting fire retardant properties to other compatible, thermoplastic polymers (including some elastomers). Examples of compatible flammable polymers include nylons, polyesters, and acrylics. Unlike most prior additives, PHA and PMeOA do not appreciably degrade the mechanical properties of the matrix polymer; indeed, in some cases, mechanical properties are enhanced. Also, unlike some prior additives, PHA and PMeOA do not decompose into large amounts of corrosive or toxic compounds during combustion and can be processed at elevated temperatures. PMeOA derivative formulations were synthesized and used as an FR additive in the fabrication of polyamide (PA) and polystyrene (PS) composites with notable reduction (>30 percent for PS) in peak heat release rates compared to the neat polymer as measured by a Cone Calorimeter (ASTM E1354). Synergistic effects were noted with nanosilica composites. These nanosilica composites had more than 50-percent reduction in peak heat release rates. In a typical application, a flammable thermoplastic, thermoplastic blend, or elastomer that one seeks to render flame-retardant is first dry-mixed with PHA or PMeOA or derivative thereof. The proportion of PHA or PMeOA or derivative in the mixture is typically chosen to lie between 1 and 20 weight percent. The dry blend can then be melt-extruded. The extruded polymer blend can further be extruded and/or molded into fibers, pipes, or any other of a variety of objects that may be required to be fire-retardant. The physical and chemical mechanisms which impart flame retardancy of the additive include inhibiting free-radical oxidation in the vapor phase, preventing vaporization of fuel (the polymer), and cooling through the formation of chemical bonds in either the vapor or the condensed phase. Under thermal stress, the cyclic hydroxyl/ methoxy component forms polybenzoxazole (PBO) in a reaction that absorbs heat from its surroundings. PBO under thermal stress cross-links, forming a protective char layer, which thermally insulates the polymer. Thus, the formation of the char layer further assists to extinguish the fire by preventing vaporization of the polymeric fuel.

Williams, Martha K.; Smith, Trent M.

2011-01-01

151

Methylotrophic Bacillus methanolicus Encodes Two Chromosomal and One Plasmid Born NAD+ Dependent Methanol Dehydrogenase Paralogs with Different Catalytic and Biochemical Properties  

PubMed Central

Bacillus methanolicus can utilize methanol as the sole carbon source for growth and it encodes an NAD+-dependent methanol dehydrogenase (Mdh), catalyzing the oxidation of methanol to formaldehyde. Recently, the genomes of the B. methanolicus strains MGA3 (ATCC53907) and PB1 (NCIMB13113) were sequenced and found to harbor three different putative Mdh encoding genes, each belonging to the type III Fe-NAD+-dependent alcohol dehydrogenases. In each strain, two of these genes are encoded on the chromosome and one on a plasmid; only one chromosomal act gene encoding the previously described activator protein ACT was found. The six Mdhs and the ACT proteins were produced recombinantly in Escherichia coli, purified, and characterized. All Mdhs required NAD+ as cosubstrate, were catalytically stimulated by ACT, exhibited a broad and different substrate specificity range and displayed both dehydrogenase and reductase activities. All Mdhs catalyzed the oxidation of methanol; however the catalytic activity for methanol was considerably lower than for most other alcohols tested, suggesting that these enzymes represent a novel class of alcohol dehydrogenases. The kinetic constants for the Mdhs were comparable when acting as pure enzymes, but together with ACT the differences were more pronounced. Quantitative PCR experiments revealed major differences with respect to transcriptional regulation of the paralogous genes. Taken together our data indicate that the repertoire of methanol oxidizing enzymes in thermotolerant bacilli is larger than expected with complex mechanisms involved in their regulation. PMID:23527128

Muller, Jonas E. N.; Kupper, Christiane E.; Schneider, Olha; Vorholt, Julia A.; Ellingsen, Trond E.; Brautaset, Trygve

2013-01-01

152

DEATH AND MENTALLY RETARDED PERSONS  

E-print Network

to [another institution]. Some authorities from juvenile court I think-there's four men with yellow hair-they asked me a bunch of questions and then they said, 'Send him to [names another institution].' I was there seven­ teen years. It was better, but you... as good as anyone else. But after the child came, I realized that I had failed everything and I didn't want to live anymore (Michaels and Schucman, 1962:570). The suicide rate among parents of retarded children is said to be twice that of the national...

Evans, Daryl

1981-01-01

153

Multi-gene silencing in Arabidopsis: a collection of artificial microRNAs targeting groups of paralogs encoding transcription factors.  

PubMed

Functional redundancy often hampers the analysis of gene families. To overcome this difficulty, we constructed Arabidopsis thaliana lines that expressed artificial microRNAs designed to simultaneously target two to six paralogous genes encoding members of transcription factor families. Of the 576 genes that we chose as targets, only 122 had already been functionally studied at some level. As a simple indicator of the inhibitory effects of our amiRNAs on their targets, we examined the amiRNA-expressing transgenic lines for morphological phenotypes at the rosette stage. Of 338 transgenes tested, 21 caused a visible morphological phenotype in leaves, a proportion that is much higher than that expected as a result of insertional mutagenesis. Also, our collection probably represents many other mutant phenotypes, not just those in leaves. This robust, versatile method enables functional examination of redundant transcription factor paralogs, and is particularly useful for genes that occur in tandem. PMID:25040904

Jover-Gil, Sara; Paz-Ares, Javier; Micol, José Luis; Ponce, María Rosa

2014-10-01

154

Paralog Re-Emergence: A Novel, Historically Contingent Mechanism in the Evolution of Antimicrobial Resistance  

PubMed Central

Evolution of resistance to drugs and pesticides poses a serious threat to human health and agricultural production. CYP51 encodes the target site of azole fungicides, widely used clinically and in agriculture. Azole resistance can evolve due to point mutations or overexpression of CYP51, and previous studies have shown that fungicide-resistant alleles have arisen by de novo mutation. Paralogs CYP51A and CYP51B are found in filamentous ascomycetes, but CYP51A has been lost from multiple lineages. Here, we show that in the barley pathogen Rhynchosporium commune, re-emergence of CYP51A constitutes a novel mechanism for the evolution of resistance to azoles. Pyrosequencing analysis of historical barley leaf samples from a unique long-term experiment from 1892 to 2008 indicates that the majority of the R. commune population lacked CYP51A until 1985, after which the frequency of CYP51A rapidly increased. Functional analysis demonstrates that CYP51A retains the same substrate as CYP51B, but with different transcriptional regulation. Phylogenetic analyses show that the origin of CYP51A far predates azole use, and newly sequenced Rhynchosporium genomes show CYP51A persisting in the R. commune lineage rather than being regained by horizontal gene transfer; therefore, CYP51A re-emergence provides an example of adaptation to novel compounds by selection from standing genetic variation. PMID:24732957

Hawkins, Nichola J.; Cools, Hans J.; Sierotzki, Helge; Shaw, Michael W.; Knogge, Wolfgang; Kelly, Steven L.; Kelly, Diane E.; Fraaije, Bart A.

2014-01-01

155

Recombineering-based dissection of flanking and paralogous Hox gene functions in mouse reproductive tracts.  

PubMed

Hox genes are key regulators of development. In mammals, the study of these genes is greatly confounded by their large number, overlapping functions and interspersed shared enhancers. Here, we describe the use of a novel recombineering strategy to introduce simultaneous frameshift mutations into the flanking Hoxa9, Hoxa10 and Hoxa11 genes, as well as their paralogs on the HoxD cluster. The resulting Hoxa9,10,11 mutant mice displayed dramatic synergistic homeotic transformations of the reproductive tracts, with the uterus anteriorized towards oviduct and the vas deferens anteriorized towards epididymis. The Hoxa9,10,11 mutant mice also provided a genetic setting that allowed the discovery of Hoxd9,10,11 redundant reproductive tract patterning function. Both shared and distinct Hox functions were defined. Hoxd9,10,11 play a crucial role in the regulation of uterine immune function. Non-coding non-polyadenylated RNAs were among the key Hox targets, with dramatic downregulation in mutants. We observed Hox cross-regulation of transcription and splicing. In addition, we observed a surprising anti-dogmatic apparent posteriorization of the uterine epithelium. In caudal regions of the uterus, the normal simple columnar epithelium flanking the lumen was replaced by a pseudostratified transitional epithelium, normally found near the more posterior cervix. These results identify novel molecular functions of Hox genes in the development of the male and female reproductive tracts. PMID:23760953

Raines, Anna M; Adam, Mike; Magella, Bliss; Meyer, Sara E; Grimes, H Leighton; Dey, Sudhansu K; Potter, S Steven

2013-07-01

156

Recombineering-based dissection of flanking and paralogous Hox gene functions in mouse reproductive tracts  

PubMed Central

Hox genes are key regulators of development. In mammals, the study of these genes is greatly confounded by their large number, overlapping functions and interspersed shared enhancers. Here, we describe the use of a novel recombineering strategy to introduce simultaneous frameshift mutations into the flanking Hoxa9, Hoxa10 and Hoxa11 genes, as well as their paralogs on the HoxD cluster. The resulting Hoxa9,10,11 mutant mice displayed dramatic synergistic homeotic transformations of the reproductive tracts, with the uterus anteriorized towards oviduct and the vas deferens anteriorized towards epididymis. The Hoxa9,10,11 mutant mice also provided a genetic setting that allowed the discovery of Hoxd9,10,11 redundant reproductive tract patterning function. Both shared and distinct Hox functions were defined. Hoxd9,10,11 play a crucial role in the regulation of uterine immune function. Non-coding non-polyadenylated RNAs were among the key Hox targets, with dramatic downregulation in mutants. We observed Hox cross-regulation of transcription and splicing. In addition, we observed a surprising anti-dogmatic apparent posteriorization of the uterine epithelium. In caudal regions of the uterus, the normal simple columnar epithelium flanking the lumen was replaced by a pseudostratified transitional epithelium, normally found near the more posterior cervix. These results identify novel molecular functions of Hox genes in the development of the male and female reproductive tracts. PMID:23760953

Raines, Anna M.; Adam, Mike; Magella, Bliss; Meyer, Sara E.; Grimes, H. Leighton; Dey, Sudhansu K.; Potter, S. Steven

2013-01-01

157

Residential Facilities for the Mentally Retarded.  

ERIC Educational Resources Information Center

The handbook on residential institutions, for professionals and students in the field of mental retardation, attempts to interpret the institution as a part of the culture which it serves, avoiding emotional responses but suggesting formulas for change. Characteristics of contemporary institutions for the mentally retarded are examined and…

Baumeister, Alfred A., Ed.; Butterfield, Earl, Ed.

158

UNDERSTANDING AND HELPING THE RETARDED READER.  

ERIC Educational Resources Information Center

THE PROCEEDINGS OF A 1962 STATEWIDE ARIZONA CONFERENCE ON READING DEVELOPMENT AND READING DIFFICULTIES INCLUDE 15 PAPERS. ARTICLES ON THE ABLE RETARDED READER ARE "UNDERSTANDING THE ABLE RETARDED READER" BY HELEN M. ROBINSON, AND "CLASSROOM PROCEDURES" BY ROSEMARY YOAKUM. PAPERS ON EMOTIONALLY DISTURBED CHILDREN ARE "IDENTIFICATION OF EMOTIONAL…

STRANG, RUTH, ED.

159

Occipital Alpha Training in Mentally Retarded Adolescents.  

ERIC Educational Resources Information Center

Retarded Ss receiving occipital alpha feedback significantly decreased their alpha density in reference to the random feedback (control) group. Results are discussed in terms of potential implications for visual attention, training techniques for mentally retarded adolescents, and other biofeedback applications. (Author)

Thorson, Gary; Lipscomb, Thomas

1982-01-01

160

Carbon Monoxide From Fibers With Fire Retardants  

Microsoft Academic Search

Carbon monoxide production was measured for selected fibers without and with fire retardants. The yield of carbon monoxide tended to decrease with increasing fire re tardant content in the majority of cases, but not in all cases. There appeared to be some fire retardant levels giving minimum yields of carbon monoxide.

Carlos J. Hilado; Patricia A. Huttlinger

1981-01-01

161

Long Term Memory in Normals and Retardates.  

ERIC Educational Resources Information Center

The study sought to determine if relationships existed among Piagetian measures of reasoning and memory, and if development of the memory process in normals and retardates is identical. Subjects were 48 normals (IQ 90-110) and 48 retardates (IQ 50-75), all CA 8-20 years. A battery of assessments, including conservation, spatial imagery, and memory…

McLaughlin, John A.; Stephens, Will Beth

162

Public Libraries and People with Mental Retardation.  

ERIC Educational Resources Information Center

This article is designed to help public libraries provide support for people with mental retardation through the implementation of "Guidelines for Library Services for People with Mental Retardation", developed by the American Library Association. Topics include needs assessment; staff training; adaptive technology; resource formats, including…

Walling, Linda Lucas

2001-01-01

163

Identifying Depression in Students with Mental Retardation.  

ERIC Educational Resources Information Center

Offers guidelines to teachers for identifying depression in students with mental retardation. Discusses prevalence and symptoms of depression, causes of depression, difficulty of diagnosis in students with mental retardation, detecting symptoms in the classroom, treatment of depression, and psychological services. Inserts list ideas for helping…

Stough, Laura M.; Baker, Lynn

1999-01-01

164

Political Philosophy and the Mentally Retarded.  

ERIC Educational Resources Information Center

The effects of Social Darwinism, eugenics, and contemporary political conservatism on the status of advocacy efforts for the mentally retarded are reviewed. Provided are historical sketches of Social Darwinism, which viewed the retarded as members of an inferior race, and eugenics, which argued for sterilization of the "genetically unfit". The…

Stanovich, Keith E.

165

Rehabilitation in Prison: The Incarcerated Retarded  

Microsoft Academic Search

Incarcerated retarded citizens have extensive needs for rehabilitation intervention. However, barriers to providing rehabilitative experiences within the correctional milieu are very substantial. The authors offer recommendations to improve the effectiveness of rehabilitation programs for retarded offenders. The authors also highlight possible pitfalls in providing such services. These pitfalls include potential negative consequences of \\

Peter M. Hayman; Robert W. Hiltonsmith; Alex W. Ursprung; Harry J. Dross

1982-01-01

166

Recreation for Retarded Teenagers and Young Adults.  

ERIC Educational Resources Information Center

Intended for recreational leaders, classroom teachers, volunteers, and parents, the text presents guidelines for planning and conducting activities for mentally retarded youth and young adults. Consideration of understanding the maturing retardate and his social needs includes different kinds of beneficial social experiences, the maturing…

Carlson, Bernice Wells; Ginglend, David R.

167

Interaction between Family Violence and Mental Retardation.  

ERIC Educational Resources Information Center

Characteristics that make individuals with mental retardation more vulnerable to family violence are discussed in the areas of child, adult, and sexual abuse. Common psychological effects of this trauma are then explored followed by implications for practice. A case study of a female with mental retardation is presented. (Contains references.)…

Strickler, Heidi

2001-01-01

168

ATTITUDE OF PARENTS TOWARDS THEIR MENTALLY RETARDED CHILDREN1  

PubMed Central

SUMMARY Parents of 50 mentally retarded children were investigated for their attitudes towards their retarded children. Both the parents showed more negative attitudes toward their severely retarded child. In general mothers exhibited more negative attitude than the fathers. PMID:22058539

Rastogi, C. K.

1981-01-01

169

Positron emission tomography methods with potential for increased understanding of mental retardation and developmental disabilities.  

PubMed

Positron emission tomography (PET) is a technique that enables imaging of the distribution of radiolabeled tracers designed to track biochemical and molecular processes in the body after intravenous injection or inhalation. New strategies for the use of radiolabeled tracers hold potential for imaging gene expression in the brain during development and following interventions. In addition, PET may be key in identifying the physiological consequences of gene mutations associated with mental retardation. The development of high spatial resolution microPET scanners for imaging of rodents provides a means for longitudinal study of transgenic mouse models of genetic disorders associated with mental retardation. In this review, we describe PET methodology, illustrate how PET can be used to delineate biochemical changes during brain development, and provide examples of how PET has been applied to study brain glucose metabolism in Rett syndrome, serotonin synthesis in autism, and GABAA receptors in Angelman's syndrome and Prader-Willi syndrome. Future application of PET scanning in the study of mental retardation might include measurements of brain protein synthesis in fragile X syndrome and tuberous sclerosis complex, two common conditions associated with mental retardation in which cellular mechanisms involve dysregulation of protein synthesis. Mental retardation results in life-long disability, and application of new PET technologies holds promise for a better understanding of the biological underpinnings of mental retardation, with the potential to uncover new treatment options. PMID:16240413

Sundaram, Senthil K; Chugani, Harry T; Chugani, Diane C

2005-01-01

170

A polymeric flame retardant additive for rubbers  

SciTech Connect

Synthesis of a polyphosphonate by the interfacial polymerization of bisphenol-A (BPA) and dichloro-phenyl phosphine oxide (DCPO) using cetyltrimethyl ammonium chloride (TMAC) as phase transfer catalyst (PTC) was reported. The polyphosphonate was characterized by elemental analysis, IR, TGA, DSC and 1H-NMR spectroscopy. The flame retardancy of the polymer was done by OI study. The polymer was used as a fire retardant additive to rubbers such as natural rubber (NR), styrene-butadiene rubber(SBR), nitrile rubber (NBR) and chloroprene rubber (CR). The efficiency of the fire retardant property of this additive was determined by LOI measurements of the various rubber samples.

Ghosh, S.N.; Maiti, S. [Indian Institute of Technology, Kharagpur (India)

1993-12-31

171

Leucine-rich repeat kinase 1: a paralog of LRRK2 and a candidate gene for Parkinson’s disease  

Microsoft Academic Search

Leucine-rich repeat kinase 1 gene (LRRK1) on chromosome 15q26.3 is a paralog of LRRK2 in which multiple substitutions were recently linked to Parkinson’s disease. We have examined the exon–intron structure of\\u000a the gene and the expressed mRNA sequence in brain. LRRK1 sequencing analysis in 95 probands from families with autosomal dominant Parkinson’s disease identified 23 variants, 14 of\\u000a which are

Julie P. Taylor; Mary M. Hulihan; Jennifer M. Kachergus; Heather L. Melrose; Sarah J. Lincoln; Kelly M. Hinkle; Jeremy T. Stone; Owen A. Ross; Robert Hauser; Jan Aasly; Thomas Gasser; Haydeh Payami; Zbigniew K. Wszolek; Matthew J. Farrer

2007-01-01

172

Evolution of the vertebrate genome as reflected in paralogous chromosomal regions in man and the house mouse  

SciTech Connect

Gene constellations on several human chromosomes are interpreted as indications of large regional duplications that took place during evolution of the vertebrate genome. Four groups of paralogous chromosomal regions in man and the house mouse are suggested and are believed to be conserved remnants of the two or three rounds of tetraploidization that are likely to have occurred during evolution of the vertebrates. The phenomenon of differential silencing of genes is described. The importance of conservation of linkage of particular genes is discussed in relation to genetic regulation and cell differentiation. 120 refs., 5 tabs.

Lundin, L.G. (Univ. of Uppsala (Sweden))

1993-04-01

173

Clusters of ancestrally related genes that show paralogy in whole or in part are a major feature of the genomes of humans and other species.  

PubMed

Arrangements of genes along chromosomes are a product of evolutionary processes, and we can expect that preferable arrangements will prevail over the span of evolutionary time, often being reflected in the non-random clustering of structurally and/or functionally related genes. Such non-random arrangements can arise by two distinct evolutionary processes: duplications of DNA sequences that give rise to clusters of genes sharing both sequence similarity and common sequence features and the migration together of genes related by function, but not by common descent. To provide a background for distinguishing between the two, which is important for future efforts to unravel the evolutionary processes involved, we here provide a description of the extent to which ancestrally related genes are found in proximity.Towards this purpose, we combined information from five genomic datasets, InterPro, SCOP, PANTHER, Ensembl protein families, and Ensembl gene paralogs. The results are provided in publicly available datasets (http://cgd.jax.org/datasets/clustering/paraclustering.shtml) describing the extent to which ancestrally related genes are in proximity beyond what is expected by chance (i.e. form paraclusters) in the human and nine other vertebrate genomes, as well as the D. melanogaster, C. elegans, A. thaliana, and S. cerevisiae genomes. With the exception of Saccharomyces, paraclusters are a common feature of the genomes we examined. In the human genome they are estimated to include at least 22% of all protein coding genes. Paraclusters are far more prevalent among some gene families than others, are highly species or clade specific and can evolve rapidly, sometimes in response to environmental cues. Altogether, they account for a large portion of the functional clustering previously reported in several genomes. PMID:22563380

Walker, Michael B; King, Benjamin L; Paigen, Kenneth

2012-01-01

174

Physical Education: Equipment for Teaching the Retarded  

ERIC Educational Resources Information Center

Equipment designed to help mentally retarded students develop flexibility, eye-hand and eye-foot coordination, muscle coordination, body balance and control, and social involvement in their peer group. (Author/MLF)

Chaya, John

1976-01-01

175

Brominated Flame Retardants and Perfluorinated Chemicals  

EPA Science Inventory

Brominated flame retardants (BFRs) and perfluorinated chemicals (PFCs) belong to a large class of chemicals known as organohalogens. It is believed that both BFRs and PFCs saved lives by reducing flammability of materials commonly used and bactericidal (biocidal) properties. Thes...

176

HEALTH EFFECTS OF BROMINATED FLAME RETARDANTS (BFRS)  

EPA Science Inventory

Abstract Brominated flame retardant use has increased dramatically in order to provide fire safety to consumers. However, there is growing concern about widespread environmental contamination and potential health risks from some of these products. The most used products...

177

Helping Behavior Among Normal and Retarded Children  

ERIC Educational Resources Information Center

Distinctions between psychological versus task helping and attempted versus achieved help were applied to the helping behaviors of normal and retarded children of 2 age groups observed in natural settings. (Authors)

Severy, Lawrence J.; Davis, Keith E.

1971-01-01

178

Retardation analytical model to extend service life  

NASA Technical Reports Server (NTRS)

A fatigue crack growth model that incorporates crack growth retardation effects and is applicable to the materials characteristics and service environments of high performance LH2/LO2 engine systems is discussed. Future Research plans are outlined.

Matejczyk, J.

1984-01-01

179

Thermally Stable and Flame Retardant Elastomeric Nanocomposites  

Microsoft Academic Search

\\u000a This chapter is dedicated to thermally stable and flame retardant elastomeric composites. Two approaches are considered: the\\u000a synthesis of elastomeric nanocomposites, where the nanoparticles are dispersed at the nanoscale, and the incorporation of\\u000a nanofillers at high loadings where agglomerate of nanoparticles are observed in the elastomeric matrix. The chapter is mainly\\u000a focused on the key parameter influencing the flame retardancy,

O. Cerin; G. Fontaine; S. Duquesne; S. Bourbigot

180

Diagnosis and Management of Intrauterine Growth Retardation  

Microsoft Academic Search

Intrauterine growth retardation (IUGR) is associated with significant perinatal morbidity and mortality. This condition can be a sign of genetic disorders, fetal infection, uteroplacental insufficiency, or constitutionally small fetuses. Correct determination of gestational age is the first step in prenatal screening of growth-retarded fetuses. The discovery of a small-for-gestational age fetus necessitates fetal assessment for the evaluation of the etiology

J. Lepercq; D. Mahieu-Caputo

1998-01-01

181

Gitelman's syndrome: Rare presentation with growth retardation.  

PubMed

Gitelman's syndrome is an autosomal recessive disorder characterized by hypokalemic metabolic alkalosis, hypokalemia, hypomagnesaemia, hypocalciuria, hyperreninemia and without hypertension. Gitelman's syndrome is caused by mutations of the SLC12A3 gene, which encodes the Na/Cl co-transporter (NCCT) in the distal convoluted tubule. Majority of cases manifest during adolescence or adulthood and growth retardation is not the common feature. We report a rare presentation of Gitelman's syndrome in a four-year-old boy with growth retardation. PMID:24574637

Gaur, A; Ambey, R; Gaur, B K

2014-01-01

182

Understanding Substrate Selection and Functional Output of Bacterial Type IIA Topoisomerase Orthologs and Paralogs  

E-print Network

avoid permanent DNA denaturation. -Precipitate proteins etc.chloroform and EtOH precipitate. Pellet DNA, wash wwith 70%precipitate pellet. Topoisomerase Writhe Assay Topo IB Protocol: • 10 minute protein/DNA

Tretter, Elsa

2012-01-01

183

Expression pattern of two paralogs of the PI/GLO-like locus during Orchis italica (Orchidaceae, Orchidinae) flower development.  

PubMed

The class B MADS-box genes belong to two distinct functional groups: the AP3/DEF-like and the PI/GLO-like sub-families. In orchids, AP3/DEF-like genes are present in four copies, each with a different role in floral organ formation, which is described in the "orchid code" model. Interestingly, the orchid PI/GLO-like genes are present in two copies in Orchidinae, whereas they are described as single copy in the other orchid lineages. The two PI/GLO-like paralogs have site-specific different selective constraints; in addition, they show relaxation of purifying selection when compared to the single-copy lineages. In this study, we present a comparative analysis of the expression patterns of the two PI/GLO-like paralogs, OrcPI and OrcPI2, in floral tissues of Orchis italica in different developmental stages using real-time PCR. The two genes show similar expression profiles in the tissue examined, with differences detectable between immature and mature inflorescence. In all cases, OrcPI2 is expressed at a higher level than OrcPI. Real-time PCR results reveal that the co-expression of the two duplicated loci could have a fully or partially redundant function. The possible evolutionary fate of OrcPI and OrcPI2 is discussed as well as their involvement in ovary development. PMID:21892737

Salemme, Marinella; Sica, Maria; Gaudio, Luciano; Aceto, Serena

2011-10-01

184

Realidades Acerca de la Deficiencia Mental = Facts about Mental Retardation.  

ERIC Educational Resources Information Center

This document consists of two booklets, one in Spanish and one in English, both covering the same text: the characteristics of mentally retarded individuals, the prevalence of mentally retarded persons in Texas, causes of mental retardation, prevention possibilities, and services available to mentally retarded persons in Texas. A distinction is…

Texas State Dept. of Mental Health and Mental Retardation, Austin.

185

Public Attitudes Toward Mentally Retarded Children. Volume 4, Number 75.  

ERIC Educational Resources Information Center

Investigated were the attitudes of 430 adults toward mentally retarded children. In addition to providing information on demographic characteristics, definition of retardation and degree of contact with retarded people, the Ss rated 48 attitudinal statements pertaining to retarded children. Factor analysis of questionnaire responses revealed four…

Gottlieb, Jay; Corman, Louise

186

An easy-to-use primer design tool to address paralogous loci and T-DNA insertion sites in the genome of Arabidopsis thaliana  

PubMed Central

Background More than 90% of the Arabidopsis thaliana genes are members of multigene families. DNA sequence similarities present in such related genes can cause trouble, e.g. when molecularly analysing mutant alleles of these genes. Also, flanking-sequence-tag (FST) based predictions of T-DNA insertion positions are often located within paralogous regions of the genome. In such cases, the prediction of the correct insertion site must include careful sequence analyses on the one hand and a paralog specific primer design for experimental confirmation of the prediction on the other hand. Results GABI-Kat is a large A. thaliana insertion line resource, which uses in-house confirmation to provide highly reliable access to T-DNA insertion alleles. To offer trustworthy mutant alleles of paralogous loci, we considered multiple insertion site predictions for single FSTs and implemented this 1-to-N relation in our database. The resulting paralogous predictions were addressed experimentally and the correct insertion locus was identified in most cases, including cases in which there were multiple predictions with identical prediction scores. A newly developed primer design tool that takes paralogous regions into account was developed to streamline the confirmation process for paralogs. The tool is suitable for all parts of the genome and is freely available at the GABI-Kat website. Although the tool was initially designed for the analysis of T-DNA insertion mutants, it can be used for any experiment that requires locus-specific primers for the A. thaliana genome. It is easy to use and also able to design amplimers with two genome-specific primers as required for genotyping segregating families of insertion mutants when looking for homozygous offspring. Conclusions The paralog-aware confirmation process significantly improved the reliability of the insertion site assignment when paralogous regions of the genome were affected. An automatic online primer design tool that incorporates experience from the in-house confirmation of T-DNA insertion lines has been made available. It provides easy access to primers for the analysis of T-DNA insertion alleles, but it is also beneficial for other applications as well.

2014-01-01

187

In Vivo Replication of Recombinant Murine Cytomegalovirus Driven by the Paralogous Major Immediate-Early Promoter-Enhancer of Human Cytomegalovirus  

PubMed Central

Transcription of the major immediate-early (MIE) genes of cytomegaloviruses (CMV) is driven by a strong promoter-enhancer (MIEPE) complex. Transactivator proteins encoded by these MIE genes are essential for productive infection. Accordingly, the MIEPE is a crucial control point, and its regulation by activators and repressors is pertinent to virus replication. Since the MIEPE contains multiple regulatory elements, it was reasonable to assume that specific sequence motifs are irreplaceable for specifying the cell-type tropism and replication pattern. Recent work on murine CMV infectivity (A. Angulo, M. Messerle, U. H. Koszinowski, and P. Ghazal, J. Virol. 72:8502–8509, 1998) has documented the proposed enhancing function of the enhancer in that its resection or its replacement by a nonregulatory stuffer sequence resulted in a significant reduction of infectivity, even though replication competence was maintained by a basal activity of the spared authentic MIE promoter. Notably, full capacity for productive in vitro infection of fibroblasts was restored in recombinant viruses by the human CMV enhancer. Using two-color in situ hybridization with MIEPE-specific polynucleotide probes, we demonstrated that a murine CMV recombinant in which the complete murine CMV MIEPE is replaced by the paralogous human CMV core promoter and enhancer (recombinant virus mCMVhMIEPE) retained the potential to replicate in vivo in all tissues relevant to CMV disease. Notably, mCMVhMIEPE was also found to replicate in the liver, a site at which transgenic hCMV MIEPE is silenced. We conclude that productive in vivo infection with murine CMV does not strictly depend on a MIEPE type-specific regulation. PMID:10233967

Grzimek, Natascha K. A.; Podlech, Jurgen; Steffens, Hans-Peter; Holtappels, Rafaela; Schmalz, Susanne; Reddehase, Matthias J.

1999-01-01

188

Nrf2b, Novel Zebrafish Paralog of Oxidant-responsive Transcription Factor NF-E2-related Factor 2 (NRF2)*  

PubMed Central

NF-E2-related factor 2 (NRF2; also called NFE2L2) and related NRF family members regulate antioxidant defenses by activating gene expression via antioxidant response elements (AREs), but their roles in embryonic development are not well understood. We report here that zebrafish (Danio rerio), an important developmental model species, possesses six nrf genes, including duplicated nrf1 and nrf2 genes. We cloned a novel zebrafish nrf2 paralog, nrf2b. The predicted Nrf2b protein sequence shares several domains with the original Nrf2 (now Nrf2a) but lacks the Neh4 transactivation domain. Zebrafish-human comparisons demonstrate conserved synteny involving nrf2 and hox genes, indicating that nrf2a and nrf2b are co-orthologs of human NRF2. nrf2a and nrf2b displayed distinct patterns of expression during embryonic development; nrf2b was more highly expressed at all stages. Embryos in which Nrf2a expression had been knocked down with morpholino oligonucleotides were more sensitive to tert-butylhydroperoxide but not tert-butylhydroquinone, whereas knockdown of Nrf2b did not affect sensitivity of embryos to either chemical. Gene expression profiling by microarray identified a specific role for Nrf2b as a negative regulator of several genes, including p53, cyclin G1, and heme oxygenase 1, in embryos. Nrf2a and Nrf2b exhibited different mechanisms of cross-talk with the Ahr2 signaling pathway. Together, these results demonstrate distinct roles for nrf2a and nrf2b, consistent with subfunction partitioning, and identify a novel negative regulatory role for Nrf2b during development. The identification of zebrafish nrf2 co-orthologs will facilitate new understanding of the multiple roles of NRF2 in protecting vertebrate embryos from oxidative damage. PMID:22174413

Timme-Laragy, Alicia R.; Karchner, Sibel I.; Franks, Diana G.; Jenny, Matthew J.; Harbeitner, Rachel C.; Goldstone, Jared V.; McArthur, Andrew G.; Hahn, Mark E.

2012-01-01

189

Unsolved problems and unanswered questions in flame retardance of polymers  

Microsoft Academic Search

Some of the unsolved problems and unanswered questions in the flame retardance of polymers are reviewed. They include, durable flame-retardant systems for cotton; FR treatment of cotton–PET blends; durable, weatherable, non-water-leachable, FR treatment of lignocellulosic products, especially wood; better understanding of gas phase and condensed phase mechanisms of flame retardance; flame retardance by sulfur derivatives; weatherable flame-retardant coatings; lowering smoke

Menachem Lewin

2005-01-01

190

Alport syndrome, mental retardation, midface hypoplasia, and elliptocytosis: a new X linked contiguous gene deletion syndrome?  

Microsoft Academic Search

We describe a family with four members, a mother, two sons, and a daughter, who show clinical features consistent with X linked Alport syndrome. The two males presented with additional features including mental retardation, dysmorphic facies with marked midface hypoplasia, and elliptocytosis. The elliptocytosis was not associated with any detectable abnormalities in red cell membrane proteins; red cell membrane stability

J J Jonsson; A Renieri; P G Gallagher; C E Kashtan; E M Cherniske; M Bruttini; M Piccini; F Vitelli; A Ballabio; B R Pober

1998-01-01

191

Loss of WAVE-1 causes sensorimotor retardation and reduced learning and memory in mice  

E-print Network

. Soderling* , Lorene K. Langeberg*, Jacquelyn A. Soderling*, Stephen M. Davee*, Richard Simerly , Jacob Raber with 3p-syndrome mental retardation who are haploinsuf- ficient for WRP MEGAP, a component of the WAVE-1 relay signals to cytoskeletal sites through the Wiskott­Aldrich-syndrome family of scaffolding proteins

Scott, John D.

192

Plasma impregnation of wood with fire retardants  

NASA Astrophysics Data System (ADS)

The efficacy of chemical and plasma treatments with phosphate and boric compounds, and nitrogen as flame retardants on wood are compared in this study. The chemical treatment involved the conventional method of spraying the solution over the wood surface at atmospheric condition and chemical vapor deposition in a vacuum chamber. The plasma treatment utilized a dielectric barrier discharge ionizing and decomposing the flame retardants into innocuous simple compounds. Wood samples are immersed in either phosphoric acid, boric acid, hydrogen or nitrogen plasmas or a plasma admixture of two or three compounds at various concentrations and impregnated by the ionized chemical reactants. Chemical changes on the wood samples were analyzed by Fourier transform infrared spectroscopy (FTIR) while the thermal changes through thermo gravimetric analysis (TGA). Plasma-treated samples exhibit superior thermal stability and fire retardant properties in terms of highest onset temperature, temperature of maximum pyrolysis, highest residual char percentage and comparably low total percentage weight loss.

Pabeliña, Karel G.; Lumban, Carmencita O.; Ramos, Henry J.

2012-02-01

193

Depolarization and retardation of a birefringent slab.  

PubMed

Mueller matrices for normal transmission of light through a birefringent slab are formulated to analyze retardation and depolarization. A finite wave band, wedge slab, and microroughness may cause a spread in retardance, which in turn produces depolarization. The spectra of depolarization, cross-polarized transmittance, and retardance by rotating-analyzer ellipsometry are simulated for the quasi-monochromatic effect with a finite bandwidth. These spectra agree excellently with the measured spectra for a sapphire slab. The depolarization spectrum simulated for the wedge effect fits the measured spectrum in the long-wave region but is too small in the short-wave region. The depolarization simulated for incoherent multiple reflections demonstrates the oscillating structure, which is small compared with the measured depolarization. The finite bandwidth effect contributes more than the other effects to the measured depolarization of a sapphire slab. PMID:11059604

Nee, S M

2000-11-01

194

Interplay of the Serine/Threonine-Kinase StkP and the Paralogs DivIVA and GpsB in Pneumococcal Cell Elongation and Division  

PubMed Central

Despite years of intensive research, much remains to be discovered to understand the regulatory networks coordinating bacterial cell growth and division. The mechanisms by which Streptococcus pneumoniae achieves its characteristic ellipsoid-cell shape remain largely unknown. In this study, we analyzed the interplay of the cell division paralogs DivIVA and GpsB with the ser/thr kinase StkP. We observed that the deletion of divIVA hindered cell elongation and resulted in cell shortening and rounding. By contrast, the absence of GpsB resulted in hampered cell division and triggered cell elongation. Remarkably, ?gpsB elongated cells exhibited a helical FtsZ pattern instead of a Z-ring, accompanied by helical patterns for DivIVA and peptidoglycan synthesis. Strikingly, divIVA deletion suppressed the elongated phenotype of ?gpsB cells. These data suggest that DivIVA promotes cell elongation and that GpsB counteracts it. Analysis of protein-protein interactions revealed that GpsB and DivIVA do not interact with FtsZ but with the cell division protein EzrA, which itself interacts with FtsZ. In addition, GpsB interacts directly with DivIVA. These results are consistent with DivIVA and GpsB acting as a molecular switch to orchestrate peripheral and septal PG synthesis and connecting them with the Z-ring via EzrA. The cellular co-localization of the transpeptidases PBP2x and PBP2b as well as the lipid-flippases FtsW and RodA in ?gpsB cells further suggest the existence of a single large PG assembly complex. Finally, we show that GpsB is required for septal localization and kinase activity of StkP, and therefore for StkP-dependent phosphorylation of DivIVA. Altogether, we propose that the StkP/DivIVA/GpsB triad finely tunes the two modes of peptidoglycan (peripheral and septal) synthesis responsible for the pneumococcal ellipsoid cell shape. PMID:24722178

Campo, Nathalie; Cluzel, Caroline; Lavergne, Jean-Pierre; Freton, Celine; Combet, Christophe; Guiral, Sebastien; Soufi, Boumediene; Macek, Boris; Kuru, Erkin; VanNieuwenhze, Michael S.; Brun, Yves V.; Di Guilmi, Anne-Marie; Claverys, Jean-Pierre; Galinier, Anne; Grangeasse, Christophe

2014-01-01

195

Six Opsins from the Butterfly Papilio glaucus: Molecular Phylogenetic Evidence for Paralogous Origins of Red-Sensitive Visual Pigments in Insects  

E-print Network

Six Opsins from the Butterfly Papilio glaucus: Molecular Phylogenetic Evidence for Paralogous to the placement of six opsins from the swallowtail butterfly Papilio glaucus (PglRh1­ 6) in relationship to 46- izing the opsins from the swallowtail butterfly Papilio glaucus and examining their relationship other

196

Rad51 Paralog Complexes BCDX2 and CX3 Act at Different Stages in the BRCA1-BRCA2-Dependent Homologous Recombination Pathway  

PubMed Central

The Rad51 paralogs are required for homologous recombination (HR) and the maintenance of genomic stability. The molecular mechanisms by which the five vertebrate Rad51 paralogs regulate HR and genomic integrity remain unclear. The Rad51 paralogs associate with one another in two distinct complexes: Rad51B-Rad51C-Rad51D-XRCC2 (BCDX2) and Rad51C-XRCC3 (CX3). We find that the BCDX2 and CX3 complexes act at different stages of the HR pathway. In response to DNA damage, the BCDX2 complex acts downstream of BRCA2 recruitment but upstream of Rad51 recruitment. In contrast, the CX3 complex acts downstream of Rad51 recruitment but still has a marked impact on the measured frequency of homologous recombination. Both complexes are epistatic with BRCA2 and synthetically lethal with Rad52. We conclude that human Rad51 paralogs facilitate BRCA2-Rad51-dependent homologous recombination at different stages in the pathway and function independently of Rad52. PMID:23149936

Chun, Jarin; Buechelmaier, Erika S.

2013-01-01

197

Evolution of plant RNA polymerase IV/V genes: evidence of subneofunctionalization of duplicated NRPD2/NRPE2-like paralogs in Viola (Violaceae)  

PubMed Central

Background DNA-dependent RNA polymerase IV and V (Pol IV and V) are multi-subunit enzymes occurring in plants. The origin of Pol V, specific to angiosperms, from Pol IV, which is present in all land plants, is linked to the duplication of the gene encoding the largest subunit and the subsequent subneofunctionalization of the two paralogs (NRPD1 and NRPE1). Additional duplication of the second-largest subunit, NRPD2/NRPE2, has happened independently in at least some eudicot lineages, but its paralogs are often subject to concerted evolution and gene death and little is known about their evolution nor their affinity with Pol IV and Pol V. Results We sequenced a ~1500 bp NRPD2/E2-like fragment from 18 Viola species, mostly paleopolyploids, and 6 non-Viola Violaceae species. Incongruence between the NRPD2/E2-like gene phylogeny and species phylogeny indicates a first duplication of NRPD2 relatively basally in Violaceae, with subsequent sorting of paralogs in the descendants, followed by a second duplication in the common ancestor of Viola and Allexis. In Viola, the mutation pattern suggested (sub-) neofunctionalization of the two NRPD2/E2-like paralogs, NRPD2/E2-a and NRPD2/E2-b. The dN/dS ratios indicated that a 54 bp region exerted strong positive selection for both paralogs immediately following duplication. This 54 bp region encodes a domain that is involved in the binding of the Nrpd2 subunit with other Pol IV/V subunits, and may be important for correct recognition of subunits specific to Pol IV and Pol V. Across all Viola taxa 73 NRPD2/E2-like sequences were obtained, of which 23 (32%) were putative pseudogenes - all occurring in polyploids. The NRPD2 duplication was conserved in all lineages except the diploid MELVIO clade, in which NRPD2/E2-b was lost, and its allopolyploid derivates from hybridization with the CHAM clade, section Viola and section Melanium, in which NRPD2/E2-a occurred in multiple copies while NRPD2/E2-b paralogs were either absent or pseudogenized. Conclusions Following the relatively recent split of Pol IV and Pol V, our data indicate that these two multi-subunit enzymes are still in the process of specialization and each acquiring fully subfunctionalized copies of their subunit genes. Even after specialization, the NRPD2/E2-like paralogs are prone to pseudogenization and gene conversion and NRPD2 and NRPE2 copy number is a highly dynamic process modulated by allopolyploidy and gene death. PMID:20158916

2010-01-01

198

Functional Modeling Identifies Paralogous Solanesyl-diphosphate Synthases That Assemble the Side Chain of Plastoquinone-9 in Plastids*  

PubMed Central

It is a little known fact that plastoquinone-9, a vital redox cofactor of photosynthesis, doubles as a precursor for the biosynthesis of a vitamin E analog called plastochromanol-8, the physiological significance of which has remained elusive. Gene network reconstruction, GFP fusion experiments, and targeted metabolite profiling of insertion mutants indicated that Arabidopsis possesses two paralogous solanesyl-diphosphate synthases, AtSPS1 (At1g78510) and AtSPS2 (At1g17050), that assemble the side chain of plastoquinone-9 in plastids. Similar paralogous pairs were detected throughout terrestrial plant lineages but were not distinguished in the literature and genomic databases from mitochondrial homologs involved in the biosynthesis of ubiquinone. The leaves of the atsps2 knock-out were devoid of plastochromanol-8 and displayed severe losses of both non-photoactive and photoactive plastoquinone-9, resulting in near complete photoinhibition at high light intensity. Such a photoinhibition was paralleled by significant damage to photosystem II but not to photosystem I. In contrast, in the atsps1 knock-out, a small loss of plastoquinone-9, restricted to the non-photoactive pool, was sufficient to eliminate half of the plastochromanol-8 content of the leaves. Taken together, these results demonstrate that plastochromanol-8 originates from a subfraction of the non-photoactive pool of plastoquinone-9. In contrast to other plastochromanol-8 biosynthetic mutants, neither the single atsps knock-outs nor the atsps1 atsps2 double knock-out displayed any defects in tocopherols accumulation or germination. PMID:23913686

Block, Anna; Fristedt, Rikard; Rogers, Sara; Kumar, Jyothi; Barnes, Brian; Barnes, Joshua; Elowsky, Christian G.; Wamboldt, Yashitola; Mackenzie, Sally A.; Redding, Kevin; Merchant, Sabeeha S.; Basset, Gilles J.

2013-01-01

199

An evolutionary perspective on Elovl5 fatty acid elongase: comparison of Northern pike and duplicated paralogs from Atlantic salmon  

PubMed Central

Background The ability to produce physiologically critical LC-PUFA from dietary fatty acids differs greatly among teleost species, and is dependent on the possession and expression of fatty acyl desaturase and elongase genes. Atlantic salmon, as a result of a recently duplicated genome, have more of these enzymes than other fish. Recent phylogenetic studies show that Northern pike represents the closest extant relative of the preduplicated ancestral salmonid. Here we characterise a pike fatty acyl elongase, elovl5, and compare it to Atlantic salmon elovl5a and elovl5b duplicates. Results Phylogenetic analyses show that Atlantic salmon paralogs are evolving symmetrically, and they have been retained in the genome by purifying selection. Heterologous expression in yeast showed that Northern pike Elovl5 activity is indistinguishable from that of the salmon paralogs, efficiently elongating C18 and C20 substrates. However, in contrast to salmon, pike elovl5 was predominantly expressed in brain with negligible expression in liver and intestine. Conclusions We suggest that the predominant expression of Elovl5b in salmon liver and Elovl5a in salmon intestine is an adaptation, enabled by genome duplication, to a diet rich in terrestrial invertebrates which are relatively poor in LC-PUFA. Pike have retained an ancestral expression profile which supports the maintenance of PUFA in the brain but, due to a highly piscivorous LC-PUFA-rich diet, is not required in liver and intestine. Thus, the characterisation of elovl5 in Northern pike provides insights into the evolutionary divergence of duplicated genes, and the ecological adaptations of salmonids which have enabled colonisation of nutrient poor freshwaters. PMID:23597093

2013-01-01

200

BROMINATED FLAME RETARDANTS: CAUSE FOR CONCERN?  

EPA Science Inventory

Brominated flame retardants (BFRs) have routinely been added to consumer products for several decades in a successful effort to reduce fire-related injury and property damage. Recently, concern for this emerging class of chemicals has risen due to the occurrence of several class...

201

How the insanity acquittal retards treatment  

Microsoft Academic Search

In the continuing social debate about the insanity defense, little attention has been paid to the effects of the insanity acquittal on treatment. This article suggests that the insanity acquittal may retard treatment of mentally disordered and violent offenders. Failure to assign responsibility to a mentally disordered offender may lessen his\\/her initiative and emotional opportunity to make needed changes in

Robert A. Fein

1984-01-01

202

Vocational Horticulture for Persons with Mental Retardation.  

ERIC Educational Resources Information Center

The study explored methods and techniques for training mentally retarded adults to perform gardening tasks. A total of 31 subjects ages 21 to 48 (IQ range 32-89) participated in the study, which consisted of three phases. In an initial pilot study, experimentation without subjects resulted in the development of modified tools (e.g., notched…

Kern, William H.; And Others

203

Educating Students with Mild Mental Retardation.  

ERIC Educational Resources Information Center

This article examines the history of educating students with mild mental retardation and includes discussion of general demographic trends, contextual factors that influenced this process, assessment and instructional practices, and teacher roles and preparation. It then examines these same features currently and offers recommendations for…

Patton, James R.; Polloway, Edward A.; Smith, Tom E. C.

2000-01-01

204

Novel additives to retard permeable flow  

SciTech Connect

Low concentrations of surfactant and cosolute in water, can selectively retard permeable flow in high permeability rocks compared to low permeability ones. This represents a way forward for more efficient areal sweep efficiency when water flooding a reservoir during improved oil recovery. (author)

Golombok, Michael [Shell Exploration and Production, Kessler Park 1, 2288 GS Rijswijk (Netherlands); Department of Mechanical Engineering, Technische Universiteit Eindhoven, 5600 MB Eindhoven (Netherlands); Crane, Carel; Ineke, Erik; Welling, Marco [Shell Exploration and Production, Kessler Park 1, 2288 GS Rijswijk (Netherlands); Harris, Jon [Shell Exploration and Production, Kessler Park 1, 2288 GS Rijswijk (Netherlands); Shell UK Ltd., North Anderson Drive, Aberdeen, AB15 6BL (United Kingdom)

2008-09-15

205

The Year 2000 Objective for Mental Retardation.  

ERIC Educational Resources Information Center

The Centers for Disease Control (CDC) has begun a program for the prevention of disabilities, with one area of focus being developmental disabilities. An objective for the Year 2000 Health Objectives for the Nation has been proposed, stating: "By the year 2000, the prevalence of serious mental retardation (an intelligence quotient of less than 50)…

Houk, Vernon N.

206

Establishing Stimulus Equivalences among Retarded Adolescents  

ERIC Educational Resources Information Center

Four experiments were designed to determine if a visual stimulus class could be established under certain conditions for retarded adolescents, and if subjects trained to select some members of the set in response to an auditory stimulus would select all members of the set in response to that auditory stimulus. (GO)

Dixon, Michael; Spradlin, Joseph

1976-01-01

207

Implosive Therapy Treatment of Emotionally Disturbed Retardates  

ERIC Educational Resources Information Center

This study investigated the effectiveness of implosive therapy with emotionally disturbed retardates. Subjects (N=24), matched according to age, sex, race, and IQ, were randomly assigned to one treatment and two control groups. Following treatment, subjects in the implosive therapy group showed significantly more improvement than those who…

Silvestri, Richard

1977-01-01

208

Mental Retardation and Developmental Disabilities. Second Edition.  

ERIC Educational Resources Information Center

This book presents 19 chapters on life span perspectives and service issues for people with mental retardation and developmental disabilities. The book presents best practices and provides a view of the range of services necessary to work with people who have those disabilities. It is intended to provide a core reference for providers in the…

McLaughlin, Phillip J., Ed.; Wehman, Paul, Ed.

209

Pharmacotherapy in Mental Retardation and Autism.  

ERIC Educational Resources Information Center

Reviews studies examining effects of pharmacological interventions for children with mental retardation and autism. Discusses information regarding stimulants, neuroleptics, anticonvulsants, antianxiety drugs, and antidepressant drugs as measured by their effects on laboratory and clinical measures of activity level, self-injurious behavior, and…

Handen, Benjamin L.

1993-01-01

210

HEALTH ASPECTS OF BROMINATED FLAME RETARDANTS (BFRS)  

EPA Science Inventory

In order to reduce the societal costs of fires, flammability standards have been set for consumer products and equipment. Flame retardants containing bromine have constituted the largest share of this market due both to their efficiency and cost. While there are at least 75 dif...

211

BROMINATED FLAME RETARDANTS: WHY DO WE CARE?  

EPA Science Inventory

Brominated flame retardants (BFRs) save lives and property by preventing the spread of fires or delaying the time of flashover, enhancing the time people have to escape. The worldwide production of BFRs exceeded 200,000 metric tons in 2003 placing them in the high production vol...

212

Mental Retardation: Past, Present and Future  

ERIC Educational Resources Information Center

Notes that two developments had major impacts on policies towards the mentally retarded between the 1880s and the 1920s: (1) the swing toward the eugenics-heredity-genetics movement, and (2) the development of individual intelligence testing. (Author/JM)

Crissey, Marie Skodak

1975-01-01

213

Are brominated flame retardants endocrine disruptors?  

Microsoft Academic Search

Brominated flame retardants (BFRs) are a group of compounds that have received much attention recently due to their similarity with “old” classes of organohalogenated compounds such as polychlorinated biphenyls (PCBs), in terms of their fate, stability in the environment and accumulation in humans and wildlife. Toxic effects, including teratogenicity, carcinogenicity and neurotoxicity, have been observed for some BFR congeners, in

Juliette Legler; Abraham Brouwer

2003-01-01

214

Regulation of Plant Morphology by Growth Retardants  

PubMed Central

The effects of the growth retardants tetcyclacis, a norbornenodiazetine, and LAB 150 978, a dioxanylalkenyl triazole, on seedling growth and endogenous levels of phytohormone-like substances in Glycine max L. cv Maple Arrow were studied. The levels of phytohormone-like substances in the root and in the various shoot tissues were analyzed by immunoassay. After seed treatment with both compounds, shoot growth was reduced more intensively than root growth. Both compounds decreased, on a fresh weight basis, the amount of various immunoreactive gibberellins when compared with the levels in control plants, especially in the shoot tip. Likewise, the growth retardants lowered the levels of abscisic acid-like material, particularly in the primary leaf, the epicotyl and the root. In contrast, the levels of trans-zeatin-riboside and dihydrozeatin-riboside-type cytokinins were considerably elevated by the growth retardants, mainly in the primary leaf, epicotyl, and hypocotyl. On the other hand the level of isopentenyladenosine-like material was less influenced. In general, the immunoreactive 3-indoleacetic acid content in the different plant parts was changed only slightly. It is assumed that besides their effect on gibberellin content both compounds interfere directly or indirectly with the regulation of the endogenous levels of abscisic acid and cytokinins. This might be seen as an additional mode of action of growth retardants explaining some side effects on developmental processes of treated plants, e.g. delayed senescence and enhanced chlorophyll concentration in the leaves. PMID:16665554

Grossmann, Klaus; Kwiatkowski, Jacek; Siebecker, Heinrich; Jung, Johannes

1987-01-01

215

Polybrominated diphenyl ether (PBDE) flame retardants  

Microsoft Academic Search

Polybrominated diphenyl ether, PBDE, flame retardants are now a world-wide pollution problem reaching even remote areas. They have been found to bioaccumulate and there are concerns over the health effects of exposure to PBDEs, they also have potential endocrine disrupting properties. They are lipophilic compounds so are easily removed from the aqueous environment and are predicted to sorb onto sediments

Frank Rahman; Katherine H Langford; Mark D Scrimshaw; John N Lester

2001-01-01

216

TEACHING THE EDUCABLE MENTALLY RETARDED, PRACTICAL METHODS.  

ERIC Educational Resources Information Center

THIS VOLUME ADDRESSES ITSELF DIRECTLY TO PROBLEMS RELATED WITH TEACHING THE EDUCABLE MENTALLY RETARDED, AND CONTAINS NON-TECHNICAL INFORMATION, SUGGESTIONS, EXAMPLES, AND METHODS OF TEACHING FROM THE PREREADINESS STAGE TO THE PREVOCATIONAL AREAS. THE CONTENTS WHICH ARE DIRECTED TO PARENTS, TEACHERS, AND OTHER WORKERS DISCUSS CHARACTERISTICS OF THE…

GARTON, MALINDA DEAN

217

READINESS AND READING FOR THE RETARDED CHILD.  

ERIC Educational Resources Information Center

THIS TEACHER'S BOOK AND MANUAL, DESIGNED TO ACCOMPANY TWO WORKBOOKS, PRESENTS A FUNCTIONAL APPROACH TO READINESS AND READING FOR YOUNG EDUCABLE RETARDED CHILDREN. THE WORKBOOKS THEMSELVES OFFER PREPARATORY ACTIVITIES FOR CHILDREN AT THE READINESS LEVEL AND SEQUENTIAL ACTIVITIES AND MATERIALS FOR THOSE AT THE BEGINNING READING STAGE. THE TEACHER'S…

BERNSTEIN, BEBE

218

Programs for the Mentally Retarded of Denmark.  

ERIC Educational Resources Information Center

The past segregation approach to the care of the mentally handicapped in Denmark is reviewed; the present normalization-integration approach, resulting in part from parents' associations and recognizing the basic rights of the retarded, is explained. A survey is then given of the Danish system, including services, facilities, budget, and regional…

Bank-Mikkelsen, N. E.

219

Puberty in the Girl Who is Retarded.  

ERIC Educational Resources Information Center

Designed to help mothers of mentally retarded girls deal with the problems and concerns of puberty, the booklet provides information on physical and emotional changes, menstruation, masturbation, heterosexual behavior, contraception, protection against sexual aggression, the possibilities of marriage, and additional sources of information.…

Pattullo, Ann

220

Computer Assisted Instruction for the Mentally Retarded.  

ERIC Educational Resources Information Center

Computer Assisted Instruction (CAI) for the mentally retarded is described; the advantages of CAI (which generally follows the pattern of programed instruction) are listed; and the roles of the teacher and the student are summarized. The coursewriter is explained, and its use as an experimental tool discussed. Guidelines are given covering…

Providence Coll., RI.

221

Purdue extension Growth Retardants: A Promising  

E-print Network

Lafayette, IN 47907 This publication has been reviewed by: Dr. Jeff Stringer, Un. of Kentucky; Dr. George) Utility arborists were the first among those caring for trees to peer over the fence at agricultural necessary to dissolve the new generation of growth retardants in either methyl or isopropyl alcohol

222

Bolkian and Bokian Retardation in Homo Sapiens  

Microsoft Academic Search

Although a low genetic barrier is said to separate humans from apes, Homo sapiens is characterized by striking developmental and anatomical particularities. On the one hand, humans have a very extended life history (retardation). On the other hand, human anatomy shows many instances of both neoteny and hypermorphosis.

Jos Verhulst

1999-01-01

223

Bibliographic Instruction for Adults with Mental Retardation.  

ERIC Educational Resources Information Center

Conducted as part of a practicum to be completed at the Champaign (Illinois) Public Library and Information Center, this study was designed to view the availability of appropriate bibliographic instruction for adults who are mentally retarded that will enhance both their ability to use library resources and equipment, and their desire to do so.…

Norlin, Dennis A.

224

Euthanasia and Mental Retardation: Suggesting the Unthinkable.  

ERIC Educational Resources Information Center

The article examines current opinions toward euthanasia of persons with mental retardation in light of the history of public and professional attitudes. It also discusses the rejection of euthanasia on moral and religious grounds, and notes the use of lifelong incarceration, based on eugenics principles, to accomplish similar ends. (DB)

Hollander, Russell

1989-01-01

225

Training Procedure Manual for the Mentally Retarded.  

ERIC Educational Resources Information Center

Presented is a training procedure manual for institutionalized moderately, severely, and profoundly retarded persons. Teaching activities are suggested for the following skill areas: motor development and awareness (including sensory stimulation, mat skills, and music and basic rhythm); toileting; eating skills (such as straw sipping and table…

Dustin, Josephine; And Others

226

Voter Participation of Retarded Citizens in the 1976 Presidential Election  

ERIC Educational Resources Information Center

A national survey of voting patterns of retarded citizens in the 1976 presidential election indicated an increase in the number of retarded voters and in the efforts of many states to remove obstacles to voting. (CL)

Olley, J. Gregory; Ramey, Gregory

1978-01-01

227

Fire retardancy of a reactively extruded intumescent flame retardant polyethylene system enhanced by metal chelates  

Microsoft Academic Search

A reactive extrusion technology was adopted to synthesize a flame retardant (ER), based on the esterification of melamine phosphate and pentaerythritol. The ER imparts good flame retardancy and non-dripping for polyethylene (PE) when combined with ammonium polyphosphate to yield an intumescent polyethylene (PE–IFR). The performance of this intumescent system has been enhanced by the addition of small amounts (0.2%) chelated

De-Yi Wang; Yun Liu; Yu-Zhong Wang; C. Perdomo Artiles; T. Richard Hull; Dennis Price

2007-01-01

228

Decision-Making Abilities of Mothers with Mental Retardation.  

ERIC Educational Resources Information Center

The decision-making abilities of mothers with mental retardation (N=28) and contrast mothers (N=18) were compared. Results suggested that familiarity with the parenting situation as well as inherent degree of risk are of importance when one is examining decision-making for both retarded and non-retarded mothers. (Author/DB)

Tymchuk, Alexander J.; And Others

1990-01-01

229

Adaptive Behavior, Mental Retardation, and the Death Penalty  

Microsoft Academic Search

The article focuses on the assessment of adaptive behavior as a variable in the diagnosis of mental retardation in defendants charged with capital murder. A brief history of the development of adaptive behavior assessment as a major component in the determination of mental retardation is provided. Current adaptive behavior measurement instruments used in the assessment of mental retardation in adults

Kay B. Stevens; J. Randall Price

2006-01-01

230

Cardiovascular Risk Factor Levels in Adults with Mental Retardation.  

ERIC Educational Resources Information Center

Comparison of cardiovascular risk factors (blood lipids, obesity, and smoking) in 329 adults with mental retardation residing in various settings with subjects in the Framingham Offspring Study found that adults with mental retardation had cardiovascular risk profiles similar to those of individuals without mental retardation. (Author/DB)

Rimmer, James H.; And Others

1994-01-01

231

Neuropsychological Profiles of Persons with Mental Retardation and Dementia  

ERIC Educational Resources Information Center

This study examined the use of neuropsychological tests to assist in the differential diagnosis of dementia among persons with mental retardation. The author compared performances of persons with mental retardation and dementia ("n" = 10) to persons with mental retardation without dementia ("n" = 12). Participants were matched by IQ (mild or…

Palmer, Glen A.

2006-01-01

232

The Kinetics of Zeaxanthin Formation Is Retarded by Dicyclohexylcarbodiimide1  

PubMed Central

The de-epoxidation of violaxanthin to antheraxanthin (Anth) and zeaxanthin (Zeax) in the xanthophyll cycle of higher plants and the generation of nonphotochemical fluorescence quenching in the antenna of photosystem II (PSII) are induced by acidification of the thylakoid lumen. Dicyclohexylcarbodiimide (DCCD) has been shown (a) to bind to lumen-exposed carboxy groups of antenna proteins and (b) to inhibit the pH-dependent fluorescence quenching. The possible influence of DCCD on the de-epoxidation reactions has been investigated in isolated pea (Pisum sativum L.) thylakoids. The Zeax formation was found to be slowed down in the presence of DCCD. The second step (Anth ? Zeax) of the reaction sequence seemed to be more affected than the violaxanthin ? Anth conversion. Comparative studies with antenna-depleted thylakoids from plants grown under intermittent light and with unstacked thylakoids were in agreement with the assumption that binding of DCCD to antenna proteins is probably responsible for the retarded kinetics. Analyses of the DCCD-induced alterations in different antenna subcomplexes showed that Zeax formation in the PSII antenna proteins was predominantly influenced by DCCD, whereas Zeax formation in photosystem I was nearly unaffected. Our data support the suggestion that DCCD binding to PSII antenna proteins is responsible for the observed alterations in xanthophyll conversion. PMID:9625719

Heyde, Sandra; Jahns, Peter

1998-01-01

233

Nucleoid Proteins Stimulate Stringently Controlled Bacterial Promoters  

Microsoft Academic Search

We report that the H-NS nucleoid protein plays a positive role in the expression of stringently regulated genes in Escherichia coli. Bacteria lacking both H-NS and the paralog StpA show reduced growth rate. Colonies displaying an increased growth rate were isolated, and mapping of a suppressor mutation revealed a base pair substitution in the spoT gene. The spoT(A404E) mutant showed

Jörgen Johansson; Carlos Balsalobre; Su-Yan Wang; Jurate Urbonaviciene; Ding Jun Jin; Berit Sondén; Bernt Eric Uhlin

2000-01-01

234

Expression of paralogous SEP-, FUL-, AG- and STK-like MADS-box genes in wild-type and peloric Phalaenopsis flowers  

PubMed Central

The diverse flowers of Orchidaceae are the result of several major morphological transitions, among them the most studied is the differentiation of the inner median tepal into the labellum, a perianth organ key in pollinator attraction. Type A peloria lacking stamens and with ectopic labella in place of inner lateral tepals are useful for testing models on the genes specifying these organs by comparing their patterns of expression between wild-type and peloric flowers. Previous studies focused on DEFICIENS- and GLOBOSA-like MADS-box genes because of their conserved role in perianth and stamen development. The “orchid code” model summarizes this work and shows in Orchidaceae there are four paralogous lineages of DEFICIENS/AP3-like genes differentially expressed in each floral whorl. Experimental tests of this model showed the conserved, higher expression of genes from two specific DEF-like gene lineages is associated with labellum development. The present study tests whether eight MADS-box candidate SEP-, FUL-, AG-, and STK-like genes have been specifically duplicated in the Orchidaceae and are also differentially expressed in association with the distinct flower organs of Phalaenopsis hyb. “Athens.” The gene trees indicate orchid-specific duplications. In a way analogous to what is observed in labellum-specific DEF-like genes, a two-fold increase in the expression of SEP3-like gene PhaMADS7 was measured in the labellum-like inner lateral tepals of peloric flowers. The overlap between SEP3-like and DEF-like genes suggests both are associated with labellum specification and similar positional cues determine their domains of expression. In contrast, the uniform messenger levels of FUL-like genes suggest they are involved in the development of all organs and their expression in the ovary suggests cell differentiation starts before pollination. As previously reported AG-like and STK-like genes are exclusively expressed in gynostemium and ovary, however no evidence for transcriptional divergence was found in the stage investigated. Gene expression suggests a developmental regulatory system based on the combined activity of duplicate MADS-box genes. We discuss its feasibility based on documented protein interactions and patterns of expression. PMID:24659990

Acri-Nunes-Miranda, Roberta; Mondragon-Palomino, Mariana

2014-01-01

235

Brominated flame retardants: cause for concern?  

PubMed Central

Brominated flame retardants (BFRs) have routinely been added to consumer products for several decades in a successful effort to reduce fire-related injury and property damage. Recently, concern for this emerging class of chemicals has risen because of the occurrence of several classes of BFRs in the environment and in human biota. The widespread production and use of BFRs; strong evidence of increasing contamination of the environment, wildlife, and people; and limited knowledge of potential effects heighten the importance of identifying emerging issues associated with the use of BFRs. In this article, we briefly review scientific issues associated with the use of tetrabromobisphenol A, hexabromocyclododecane, and three commercial mixtures of polybrominated diphenyl ethers and discuss data gaps. Overall, the toxicology database is very limited; the current literature is incomplete and often conflicting. Available data, however, raise concern over the use of certain classes of brominated flame retardants. PMID:14698924

Birnbaum, Linda S; Staskal, Daniele F

2004-01-01

236

Retardation of ice crystallization by short peptides  

NASA Astrophysics Data System (ADS)

The effect of short peptides on the growth of ice crystals is studied using molecular dynamics simulations. The simulations focus on two sequences (Gly-Pro-Ala-Gly and Gly-Gly-Ala-Gly) that are found in collagen hydrolysate, a substance that is known to retard crystal growth. In the absence of peptides, the growth of ice crystal in the solution with the ice/water interface is observed in at a rate comparable to the experimental data. When peptides are present in the liquid phase, the crystal growth is retarded to a significant extent compared to the pure water. It is found that Gly-Pro-Ala-Gly is more effective (crystallization is up to 5 times slower than in its absence) than Gly-Gly-Ala-Gly (up to 3 times slower) implying that the role of the proline residue is important. The mechanism can be understood in the nature of binding of the peptides to the growing crystal.

Kim, Jun Soo; Yethiraj, Arun

2009-03-01

237

Domain duplication, divergence, and loss events in vertebrate Msx paralogs reveal phylogenomically informed disease markers  

PubMed Central

Background Msx originated early in animal evolution and is implicated in human genetic disorders. To reconstruct the functional evolution of Msx and inform the study of human mutations, we analyzed the phylogeny and synteny of 46 metazoan Msx proteins and tracked the duplication, diversification and loss of conserved motifs. Results Vertebrate Msx sequences sort into distinct Msx1, Msx2 and Msx3 clades. The sister-group relationship between MSX1 and MSX2 reflects their derivation from the 4p/5q chromosomal paralogon, a derivative of the original "MetaHox" cluster. We demonstrate physical linkage between Msx and other MetaHox genes (Hmx, NK1, Emx) in a cnidarian. Seven conserved domains, including two Groucho repression domains (N- and C-terminal), were present in the ancestral Msx. In cnidarians, the Groucho domains are highly similar. In vertebrate Msx1, the N-terminal Groucho domain is conserved, while the C-terminal domain diverged substantially, implying a novel function. In vertebrate Msx2 and Msx3, the C-terminal domain was lost. MSX1 mutations associated with ectodermal dysplasia or orofacial clefting disorders map to conserved domains in a non-random fashion. Conclusion Msx originated from a MetaHox ancestor that also gave rise to Tlx, Demox, NK, and possibly EHGbox, Hox and ParaHox genes. Duplication, divergence or loss of domains played a central role in the functional evolution of Msx. Duplicated domains allow pleiotropically expressed proteins to evolve new functions without disrupting existing interaction networks. Human missense sequence variants reside within evolutionarily conserved domains, likely disrupting protein function. This phylogenomic evaluation of candidate disease markers will inform clinical and functional studies. PMID:19154605

Finnerty, John R; Mazza, Maureen E; Jezewski, Peter A

2009-01-01

238

Walking Habits of Adults with Mental Retardation  

ERIC Educational Resources Information Center

The walking activity of men and women with mental retardation residing in community settings was described. Participants were 38 women (M age = 0.7, SD = 9.5) and 65 men (M age = 35.9, SD = 11.2). They wore pedometers for 7 days. A 2 ? 2 factorial ANOVA indicated no significant gender differences in total step counts or between participants with…

Stanish, Heidi I.; Draheim, Christopher C.

2005-01-01

239

Development of flame retardant, low aggressivity cables  

NASA Astrophysics Data System (ADS)

The construction of a fire retardant, low aggressivity cable may, depending upon the severity of application, require four components based on polymer insulation, fire barrier tape, bedding and sheath. A number of high performance polymers have been evaluated as insulation materials, whilst STC have developed a range of bedding and sheathing materials, both thermoplastic and crosslinkable, to meet the exacting requirements of industrial and military users.

Bury, J. R.; Cranfield, B. A.

240

Retardation of ice crystallization by short peptides  

Microsoft Academic Search

The effect of short peptides on the growth of ice crystals is studied using molecular dynamics simulations. The simulations focus on two sequences (Gly-Pro-Ala-Gly and Gly-Gly-Ala-Gly) that are found in collagen hydrolysate, a substance that is known to retard crystal growth. In the absence of peptides, the growth of ice crystal in the solution with the ice\\/water interface is observed

Jun Soo Kim; Arun Yethiraj

2009-01-01

241

Homology Modeling and Domain Interactions in Fetal Serum Protein  

NSDL National Science Digital Library

This exercise is intended to engage students to design, model, visualize and evaluate the theoretical three dimensional image of a protein whose structure has not yet been determined. The phylogenetic analysis in Biology Workbench of paralogs and orthologs to alphafetoprotein reveals more divergent sequences within active site domains of related proteins without biological activity and greater conservation of the alphafetoprotein active domain between different species.

Steve Festin (Hamilton College;)

2003-10-12

242

Identification of two paralogous caprine CD36 genes that display highly divergent mRNA expression profiles.  

PubMed

The CD36 molecule plays a pivotal role in a variety of immunological and cellular processes, including pathogen recognition, inflammation and apoptosis. Herein, we demonstrate that this gene is duplicated in goats, with two copies (CD36 and CD36-like) that display highly divergent mRNA expression profiles. In this way, CD36 mRNA is mostly expressed in the adipose tissue and heart whilst CD36-like mRNA shows a high expression in the liver. We have also found evidence of the presence of two paralogous CD36 and CD36-like genes in the bovine genome, suggesting that CD36 duplication took place before goat-cattle radiation, i.e. at least 20 MYR ago. Finally, we have characterized the polymorphism of the coding regions of the goat CD36 and CD36-like genes. In doing so, we have identified one synonymous polymorphism at the CD36-like gene (c.390A>C) that displays a significant association (P=0.04) with milk somatic cell count, a parameter often used to diagnose mastitis in domestic ruminants. PMID:22989464

Zidi, A; Castelló, A; Jordana, J; Carrizosa, J; Urrutia, B; Serradilla, J M; Amills, M

2013-01-01

243

AtGEN1 and AtSEND1, Two Paralogs in Arabidopsis, Possess Holliday Junction Resolvase Activity.  

PubMed

Holliday junctions (HJs) are physical links between homologous DNA molecules that arise as central intermediary structures during homologous recombination and repair in meiotic and somatic cells. It is necessary for these structures to be resolved to ensure correct chromosome segregation and other functions. In eukaryotes, including plants, homologs of a gene called XPG-like endonuclease1 (GEN1) have been identified that process HJs in a manner analogous to the HJ resolvases of phages, archaea, and bacteria. Here, we report that Arabidopsis (Arabidopsis thaliana), a eukaryotic organism, has two functional GEN1 homologs instead of one. Like all known eukaryotic resolvases, AtGEN1 and Arabidopsis single-strand DNA endonuclease1 both belong to class IV of the Rad2/XPG family of nucleases. Their resolvase activity shares the characteristics of the Escherichia coli radiation and UV sensitive C paradigm for resolvases, which involves resolving HJs by symmetrically oriented incisions in two opposing strands. This leads to ligatable products without the need for further processing. The observation that the sequence context influences the cleavage by the enzymes can be interpreted as a hint for the existence of sequence specificity. The two Arabidopsis paralogs differ in their preferred sequences. The precise cleavage positions observed for the resolution of mobile nicked HJs suggest that these cleavage positions are determined by both the substrate structure and the sequence context at the junction point. PMID:25037209

Bauknecht, Markus; Kobbe, Daniela

2014-09-01

244

Divergent Evolutionary and Expression Patterns between Lineage Specific New Duplicate Genes and Their Parental Paralogs in Arabidopsis thaliana  

PubMed Central

Gene duplication is an important mechanism for the origination of functional novelties in organisms. We performed a comparative genome analysis to systematically estimate recent lineage specific gene duplication events in Arabidopsis thaliana and further investigate whether and how these new duplicate genes (NDGs) play a functional role in the evolution and adaption of A. thaliana. We accomplished this using syntenic relationship among four closely related species, A. thaliana, A. lyrata, Capsella rubella and Brassica rapa. We identified 100 NDGs, showing clear origination patterns, whose parental genes are located in syntenic regions and/or have clear orthologs in at least one of three outgroup species. All 100 NDGs were transcribed and under functional constraints, while 24% of the NDGs have differential expression patterns compared to their parental genes. We explored the underlying evolutionary forces of these paralogous pairs through conducting neutrality tests with sequence divergence and polymorphism data. Evolution of about 15% of NDGs appeared to be driven by natural selection. Moreover, we found that 3 NDGs not only altered their expression patterns when compared with parental genes, but also evolved under positive selection. We investigated the underlying mechanisms driving the differential expression of NDGs and their parents, and found a number of NDGs had different cis-elements and methylation patterns from their parental genes. Overall, we demonstrated that NDGs acquired divergent cis-elements and methylation patterns and may experience sub-functionalization or neo-functionalization influencing the evolution and adaption of A. thaliana. PMID:24009676

Wang, Jun; Marowsky, Nicholas C.; Fan, Chuanzhu

2013-01-01

245

Interactome Analyses of Mature ?-Secretase Complexes Reveal Distinct Molecular Environments of Presenilin (PS) Paralogs and Preferential Binding of Signal Peptide Peptidase to PS2*  

PubMed Central

?-Secretase plays a pivotal role in the production of neurotoxic amyloid ?-peptides (A?) in Alzheimer disease (AD) and consists of a heterotetrameric core complex that includes the aspartyl intramembrane protease presenilin (PS). The human genome codes for two presenilin paralogs. To understand the causes for distinct phenotypes of PS paralog-deficient mice and elucidate whether PS mutations associated with early-onset AD affect the molecular environment of mature ?-secretase complexes, quantitative interactome comparisons were undertaken. Brains of mice engineered to express wild-type or mutant PS1, or HEK293 cells stably expressing PS paralogs with N-terminal tandem-affinity purification tags served as biological source materials. The analyses revealed novel interactions of the ?-secretase core complex with a molecular machinery that targets and fuses synaptic vesicles to cellular membranes and with the H+-transporting lysosomal ATPase macrocomplex but uncovered no differences in the interactomes of wild-type and mutant PS1. The catenin/cadherin network was almost exclusively found associated with PS1. Another intramembrane protease, signal peptide peptidase, predominantly co-purified with PS2-containing ?-secretase complexes and was observed to influence A? production. PMID:23589300

Jeon, Amy Hye Won; Bohm, Christopher; Chen, Fusheng; Huo, Hairu; Ruan, Xueying; Ren, Carl He; Ho, Keith; Qamar, Seema; Mathews, Paul M.; Fraser, Paul E.; Mount, Howard T. J.; St George-Hyslop, Peter; Schmitt-Ulms, Gerold

2013-01-01

246

Functional Analysis of Paralogous Thiol-disulfide Oxidoreductases in Streptococcus gordonii*  

PubMed Central

Disulfide bonds are important for the stability of many extracellular proteins, including bacterial virulence factors. Formation of these bonds is catalyzed by thiol-disulfide oxidoreductases (TDORs). Little is known about their formation in Gram-positive bacteria, particularly among facultative anaerobic Firmicutes, such as streptococci. To investigate disulfide bond formation in Streptococcus gordonii, we identified five putative TDORs from the sequenced genome. Each of the putative TDOR genes was insertionally inactivated with an erythromycin resistance cassette, and the mutants were analyzed for autolysis, extracellular DNA release, biofilm formation, bacteriocin production, and genetic competence. This analysis revealed a single TDOR, SdbA, which exhibited a pleiotropic mutant phenotype. Using an in silico analysis approach, we identified the major autolysin AtlS as a natural substrate of SdbA and showed that SdbA is critical to the formation of a disulfide bond that is required for autolytic activity. Analysis by BLAST search revealed homologs to SdbA in other Gram-positive species. This study provides the first in vivo evidence of an oxidoreductase, SdbA, that affects multiple phenotypes in a Gram-positive bacterium. SdbA shows low sequence homology to previously identified oxidoreductases, suggesting that it may belong to a different class of enzymes. Our results demonstrate that SdbA is required for disulfide bond formation in S. gordonii and indicate that this enzyme may represent a novel type of oxidoreductase in Gram-positive bacteria. PMID:23615907

Davey, Lauren; Ng, Crystal K. W.; Halperin, Scott A.; Lee, Song F.

2013-01-01

247

Evidence that soyasaponin Bb retards disease progression in a murine model of polycystic kidney disease  

Microsoft Academic Search

Evidence that soyasaponin Bb retards disease progression in a murine model of polycystic kidney disease.BackgroundWe reported a lessened cyst growth in the pcy mouse model of polycystic kidney disease (PKD) when mice were fed a soy protein isolate (SPI)–based diet and hypothesized that the soyasaponins may be associated with this therapeutic effect. The effects of feeding a saponin-enriched alcohol extract

Diana J Philbrick; Dominique P Bureau; F William Collins; Bruce J Holub

2003-01-01

248

Linking energy production and protein synthesis in hydrogenotrophic methanogens  

PubMed Central

Hydrogenotrophic methanogens possessing the hydrogen-dependent dehydrogenase Hmd also encode paralogs of this protein whose function is poorly understood. Here we present biochemical evidence that the two inactive Hmd paralogs of Methanocaldococcus jannaschii, HmdII and HmdIII, form binary and ternary complexes with several components of the protein translation apparatus. HmdII and HmdIII, but not the active dehydrogenase Hmd, bind with micromolar binding affinities to a number of tRNAs, and form ternary complexes with tRNAPro and prolyl-tRNA synthetase (ProRS). Fluorescence spectroscopy experiments also suggest that binding of HmdII and ProRS involves distinct binding determinants on the tRNA. These biochemical data suggest the possibility of a regulatory link between energy production and protein translation pathways that may allow a rapid cellular response to altered environmental conditions. PMID:22401293

Oza, Javin P.; Sowers, Kevin R.; Perona, John J.

2012-01-01

249

Electrode contamination effects of retarding potential analyzer.  

PubMed

The electrode contamination in electrostatic analyzers such as Langmuir probes and retarding potential analyzers (RPA) is a serious problem for space measurements. The contamination layer acts as extra capacitance and resistance and leads to distortion in the measured I-V curve, which leads to erroneous measurement results. There are two main effects of the contamination layer: one is the impedance effect and the other is the charge attachment and accumulation due to the capacitance. The impedance effect can be reduced or eliminated by choosing the proper sweeping frequency. However, for RPA the charge accumulation effect becomes serious because the capacitance of the contamination layer is much larger than that of the Langmuir probe of similar dimension. The charge accumulation on the retarding potential grid causes the effective potential, that ions experience, to be changed from the applied voltage. Then, the number of ions that can pass through the retarding potential grid to reach the collector and, thus, the measured ion current are changed. This effect causes the measured ion drift velocity and ion temperature to be changed from the actual values. The error caused by the RPA electrode contamination is expected to be significant for sounding rocket measurements with low rocket velocity (1-2 km/s) and low ion temperature of 200-300 K in the height range of 100-300 km. In this paper we discuss the effects associated with the RPA contaminated electrodes based on theoretical analysis and experiments performed in a space plasma operation chamber. Finally, the development of a contamination-free RPA for sounding rocket missions is presented. PMID:24517809

Fang, H K; Oyama, K-I; Cheng, C Z

2014-01-01

250

Proteins.  

ERIC Educational Resources Information Center

Examines proteins which give rise to structure and, by virtue of selective binding to other molecules, make genes. Binding sites, amino acids, protein evolution, and molecular paleontology are discussed. Work with encoding segments of deoxyribonucleic acid (exons) and noncoding stretches (introns) provides new information for hypotheses. (DH)

Doolittle, Russell F.

1985-01-01

251

Proteins  

NSDL National Science Digital Library

Laboratory manual and supplemental resources that were developed for a college laboratory course in protein purification. The enzyme, Beta-galactosidase, is purified in two steps, with analysis and verification of results. Course materials are divided into four units: Why Proteins, Assays, The Purification Process, and Analysis and Verification. Powerpoint lectures and study guides are provided.

Mowery, Jeanette; Seidman, Lisa A.

2009-10-01

252

?-Thalassemia, Mental Retardation, and Myelodysplastic Syndrome  

PubMed Central

This article describes three rare syndromes in which the presence of ?-thalassemia provided an important clue to the molecular basis of the underlying condition. It exemplifies how rare diseases allied with careful clinical observation can lead to important biological principles. Two of the syndromes, ATR-16 and ATR-X, are characterized by ?-thalassemia in association with multiple developmental abnormalities including mental retardation. The third condition, ATMDS, is an acquired disorder in which ?-thalassemia arises in the context of myelodysplasia. Intriguingly, mutations in the chromatin remodeling factor, ATRX, are common to both ATR-X syndrome and ATMDS. PMID:23028133

Gibbons, Richard J.

2012-01-01

253

Cloning and characterization of the promoter regions from the parent and paralogous creatine transporter genes.  

PubMed

Interconversion between phosphocreatine and creatine, catalyzed by creatine kinase is crucial in the supply of ATP to tissues with high energy demand. Creatine's importance has been established by its use as an ergogenic aid in sport, as well as the development of intellectual disability in patients with congenital creatine deficiency. Creatine biosynthesis is complemented by dietary creatine uptake. Intracellular transport of creatine is carried out by a creatine transporter protein (CT1/CRT/CRTR) encoded by the SLC6A8 gene. Most tissues express this gene, with highest levels detected in skeletal muscle and kidney. There are lower levels of the gene detected in colon, brain, heart, testis and prostate. The mechanism(s) by which this regulation occurs is still poorly understood. A duplicated unprocessed pseudogene of SLC6A8-SLC6A10P has been mapped to chromosome 16p11.2 (contains the entire SLC6A8 gene, plus 2293 bp of 5'flanking sequence and its entire 3'UTR). Expression of SLC6A10P has so far only been shown in human testis and brain. It is still unclear as to what is the function of SLC6A10P. In a patient with autism, a chromosomal breakpoint that intersects the 5'flanking region of SLC6A10P was identified; suggesting that SLC6A10P is a non-coding RNA involved in autism. Our aim was to investigate the presence of cis-acting factor(s) that regulate expression of the creatine transporter, as well as to determine if these factors are functionally conserved upstream of the creatine transporter pseudogene. Via gene-specific PCR, cloning and functional luciferase assays we identified a 1104 bp sequence proximal to the mRNA start site of the SLC6A8 gene with promoter activity in five cell types. The corresponding 5'flanking sequence (1050 bp) on the pseudogene also had promoter activity in all 5 cell lines. Surprisingly the pseudogene promoter was stronger than that of its parent gene in 4 of the cell lines tested. To the best of our knowledge, this is the first experimental evidence of a pseudogene with stronger promoter activity than its parental gene. PMID:24144841

Ndika, Joseph D T; Lusink, Vera; Beaubrun, Claudine; Kanhai, Warsha; Martinez-Munoz, Cristina; Jakobs, Cornelis; Salomons, Gajja S

2014-01-10

254

Characterization of two paralogous StAR genes in a teleost, Nile tilapia (Oreochromis niloticus).  

PubMed

Steroidogenic acute regulatory protein (StAR) transports cholesterol, the substrate for steroid synthesis, to the inner membranes of mitochondria. It is well known that estrogen is essential for female sex determination/differentiation in fish. However, no reports showed that the conventional StAR, which was supposed to be essential for estrogen production, was expressed in female gonads during the critical timing of sex determination/differentiation. In this study, two different StAR isoforms, named as StAR1 and StAR2, were characterized from the gonads of Nile tilapia (Oreochromis niloticus). Phylogenetic and synteny analysis revealed that two StAR genes existed in teleosts, Xenopus and chicken indicating that the duplication event occurred before the divergence of teleosts and tetrapods. Real-time PCR revealed that StAR1 was dominantly expressed in the testis, head kidney and kidney; while StAR2 was expressed exclusively in the gonads. In situ hybridization and immunohistochemistry demonstrated that StAR1 was expressed in the interrenal cells of the head kidney and Leydig cells of the testis; while StAR2 was expressed in the Leydig cells of the testis and the interstitial cells of the ovary. Ontogenic analysis demonstrated that StAR2 was expressed abundantly from 5 days after hatching (dah) in the somatic cells in XX gonads, whereas in XY gonads, both StARs could be detected from 30 dah until adulthood. Intraperitoneal injection of human chorionic gonadotropin experiments showed that expression of StAR1 and 2 was significantly elevated at 8h and persisted until 24h after injection in the testis. Taken together, our data suggested that StAR1 is likely to be required for cortisol production in the head kidney, and StAR2 is probably involved in estrogen production during early sex differentiation in XX gonads. In contrast, both StARs might be required for androgen production in testes. For the first time, our data demonstrated that two fish StARs might be involved in steroidogenesis in a tissue and developmental stage dependent manner. PMID:24859646

Yu, Xiangguo; Wu, Limin; Xie, Lang; Yang, Shijie; Charkraborty, Tapas; Shi, Hongjuan; Wang, Deshou; Zhou, Linyan

2014-07-01

255

Hemizygosity of delta-catenin (CTNND2) is associated with severe mental retardation in cri-du-chat syndrome.  

PubMed

Delta-catenin is an adherens junction protein involved in cell motility and expressed early in neuronal development. It was discovered as an interactor with presenilin-1. The genomic structure of the human delta-catenin gene (Human Gene Nomenclature Committee-approved symbol CTNND2) was determined and mapped to 5p15.2. A deletion of this chromosomal region has been associated with the cri-du-chat syndrome (CDCS), a segmental aneusomy syndrome of 5p that is associated with an unusual high-pitched cry at birth, facial dysmorphology, poor growth, and severe mental retardation. delta-catenin maps to a specific region in 5p15.2 that has been implicated in the mental retardation phenotype. The breakpoints in patients with 5p terminal deletions were characterized with respect to the severity of mental retardation and the physical location of the delta-catenin gene. A strong correlation was found between the hemizygous loss of delta-catenin and severe mental retardation. These findings and the properties of delta-catenin as a neuronal-specific protein, expressed early in development and involved in cell motility, support its role in the mental retardation of CDCS when present in only one copy. PMID:10673328

Medina, M; Marinescu, R C; Overhauser, J; Kosik, K S

2000-01-15

256

Independent Birth of a Novel TRIMCyp in Tupaia belangeri with a Divergent Function from Its Paralog TRIM5.  

PubMed

The origin of novel genes and their evolutionary fates are long-standing questions in evolutionary biology. These questions become more complicated for genes conserved across various lineages, such as TRIM5, an antiretroviral restriction factor and a retrovirus capsid sensor in immune signaling. TRIM5 has been subjected to numerous pathogenic challenges and undergone dynamic evolution, making it an excellent example for studying gene diversification. Previous studies among several species showed that TRIM5 gained genetic and functional novelty in a lineage-specific manner, either through gene duplication or a cyclophilin A retrotransposing into the TRIM5 locus, creating the gene fusion known as TRIM5-Cyclophilin A (TRIMCyp). To date, the general pattern of TRIM5 across the mammalian lineage remains elusive. In this study, we surveyed 36 mammalian genomes to verify a potentially novel TRIM5 pattern that uniquely seems to have occurred in tree shrews (Tupaia belangeri), and found that both gene duplication and retrotransposition worked jointly to form a specific TRIM5/TRIMCyp cluster not found among other mammals. Evolutionary analyses showed that tree shrew TRIMCyp (tsTRIMCyp) originated independently in comparison with previously reported TRIMCyps and underwent strong positive selection, whereas no signal of positive selection was detected for other tree shrew TRIM5 (tsTRIM5) genes. Functional assay results suggest a functional divergence between tsTRIMCyp and its closest paralog TRIM5-4, likely reflecting different fates under diverse evolutionary forces. These findings present a rare example of novel gene origination resulting from a combination of gene duplication, retrotransposition, and exon shuffling processes, providing a new paradigm to study genetic innovations and evolutionary fates of duplicated genes. PMID:25135944

Mu, Dan; Yang, Hui; Zhu, Jia-Wu; Liu, Feng-Liang; Tian, Ren-Rong; Zheng, Hong-Yi; Han, Jian-Bao; Shi, Peng; Zheng, Yong-Tang

2014-11-01

257

On the Use of Gene Ontology Annotations to Assess Functional Similarity among Orthologs and Paralogs: A Short Report.  

PubMed

A recent paper (Nehrt et al., PLoS Comput. Biol. 7:e1002073, 2011) has proposed a metric for the "functional similarity" between two genes that uses only the Gene Ontology (GO) annotations directly derived from published experimental results. Applying this metric, the authors concluded that paralogous genes within the mouse genome or the human genome are more functionally similar on average than orthologous genes between these genomes, an unexpected result with broad implications if true. We suggest, based on both theoretical and empirical considerations, that this proposed metric should not be interpreted as a functional similarity, and therefore cannot be used to support any conclusions about the "ortholog conjecture" (or, more properly, the "ortholog functional conservation hypothesis"). First, we reexamine the case studies presented by Nehrt et al. as examples of orthologs with divergent functions, and come to a very different conclusion: they actually exemplify how GO annotations for orthologous genes provide complementary information about conserved biological functions. We then show that there is a global ascertainment bias in the experiment-based GO annotations for human and mouse genes: particular types of experiments tend to be performed in different model organisms. We conclude that the reported statistical differences in annotations between pairs of orthologous genes do not reflect differences in biological function, but rather complementarity in experimental approaches. Our results underscore two general considerations for researchers proposing novel types of analysis based on the GO: 1) that GO annotations are often incomplete, potentially in a biased manner, and subject to an "open world assumption" (absence of an annotation does not imply absence of a function), and 2) that conclusions drawn from a novel, large-scale GO analysis should whenever possible be supported by careful, in-depth examination of examples, to help ensure the conclusions have a justifiable biological basis. PMID:22359495

Thomas, Paul D; Wood, Valerie; Mungall, Christopher J; Lewis, Suzanna E; Blake, Judith A

2012-01-01

258

Long Term Memory in Normals and Retardates. Memory and Mental Imagery in Retardates: A Pilot Study.  

ERIC Educational Resources Information Center

Two studies are reported. The first is based on Piaget's assertion that the child's representation of his world is dependent on the level of cognitive development at which he is currently functioning. Forty-eight normals and 48 retardates were given a visual memory task. They were asked to recall a configural presentation in a number of ways,…

McLaughlin, John A.; And Others

259

Growth and sexual maturity pattern of girls with mental retardation  

PubMed Central

Background: Growth of mentally retarded children differs from that of normal children. However, the adolescent growth and development of Indian mentally retarded children has not been studied. Aim: This study was conducted to evaluate the physical growth and sexual development of adolescent mentally retarded girls in North Indian population and to compare it with that of normal girls of same age group. Materials and Methods: One hundred mentally retarded (intelligence quotient (IQ) less than 70) and 100 normal girls between 10 and 20 years of age were categorized into 1-year age groups. Their height was measured and the sexual development was assessed based on breast development (BD) and pubic hair growth (PH) stages 1-5 on the basis of Tanner scale. The data was then compared between the two groups using Student's t-test. The mean age of menarche was calculated by applying Probit analysis. Results: The mean height of mentally retarded girls was significantly retarded as compared to normal girls at all ages; however, the mean height gain during 11-20 years was same in both the groups. The mentally retarded girls also showed significant retardation in PH growth at 15-17 years and in BD at 15-16 years of age. Conclusions: The physical growth and sexual development of adolescent mentally retarded girls was retarded as compared to the normal girls. The physical growth retardation occurred during early childhood (before 11 years), however the retardation in sexual maturity occurred during middle adolescence, between 15-17 years of age. PMID:24600577

Baidwan, Sukhinder; Paul, Molly M; Chhatwal, Jugesh; Deswal, RS

2014-01-01

260

ASSESSMENT OF MENTAL RETARDATION : NEED FOR NEWER APPROACHES*  

PubMed Central

SUMMARY Mental retardation is a complex, multifaceted condition. It is not a simple condition based primarily on intellectual capacities. Assessment of a retarded child should not be limited to intellectual functioning alone. It should give an idea of the individual?s strength and weaknesses globally. Unfortunately, in India, assessment of mental retardation is still primarily based on intelligence tests. There is a need to understand the limitations of such an approach. PMID:21927406

Nizamie, Alka; Nizamie, S. Haque; James, M.X.; Shukla, T.R.

1989-01-01

261

40 CFR 201.14 - Standard for retarders.  

...CONTINUED) NOISE ABATEMENT PROGRAMS NOISE EMISSION STANDARDS FOR TRANSPORTATION EQUIPMENT; INTERSTATE RAIL CARRIERS Interstate Rail Carrier Operations Standards § 201.14 Standard for retarders. Effective January 15,...

2014-07-01

262

Ramipril retards development of aortic valve stenosis in a rabbit model: mechanistic considerations  

PubMed Central

BACKGROUND AND PURPOSE Aortic valve stenosis (AVS) is associated with significant cardiovascular morbidity and mortality. To date, no therapeutic modality has been shown to be effective in retarding AVS progression. We evaluated the effect of angiotensin-converting enzyme inhibition with ramipril on disease progression in a recently developed rabbit model of AVS. EXPERIMENTAL APPROACH The effects of 8 weeks of treatment with either vitamin D2 at 25 000 IU for 4 days a week alone or in combination with ramipril (0.5 mg·kg?1) on aortic valve structure and function were examined in New Zealand white rabbits. Echocardiographic aortic valve backscatter (AVBS) and aortic valve : outflow tract flow velocity ratio were utilized to quantify changes in valve structure and function. KEY RESULTS Treatment with ramipril significantly reduced AVBS and improved aortic valve : outflow tract flow velocity ratio. The intravalvular content of the pro-oxidant thioredoxin-interacting protein was decreased significantly with ramipril treatment. Endothelial function, as measured by asymmetric dimethylarginine concentrations and vascular responses to ACh, was improved significantly with ramipril treatment. CONCLUSIONS AND IMPLICATIONS Ramipril retards the development of AVS, reduces valvular thioredoxin-interacting protein accumulation and limits endothelial dysfunction in this animal model. These findings provide important insights into the mechanisms of AVS development and an impetus for future human studies of AVS retardation using an angiotensin-converting enzyme inhibitor. PMID:20958293

Ngo, Doan TM; Stafford, Irene; Sverdlov, Aaron L; Qi, Weier; Wuttke, Ronald D; Zhang, Yuan; Kelly, Darren J; Weedon, Helen; Smith, Malcolm D; Kennedy, Jennifer A; Horowitz, John D

2011-01-01

263

Maternal caffeine intake and intrauterine growth retardation.  

PubMed

This study estimates the effect of maternal caffeine consumption throughout pregnancy on fetal growth. We studied 2,714 women who delivered a liveborn infant between 1988 and 1991. Detailed information regarding coffee, tea, and soda drinking during the first and third trimesters of pregnancy was obtained. Average caffeine intake during month 1 of pregnancy was higher than for month 7 (72.4 vs 54.0 mg per day). Consumption of >300 mg caffeine per day during month 1 (adjusted odds ratio = 0.91; 95% confidence interval = 0.44--1.90) and during month 7 (adjusted odds ratio = 1.00; 95% confidence interval = 0.37--2.70) was not associated with intrauterine growth retardation. There was little evidence for any effect modification due to cigarette smoking on the caffeine associations. This study provides evidence that antenatal caffeine consumption has no adverse effect on fetal growth. PMID:11428387

Grosso, L M; Rosenberg, K D; Belanger, K; Saftlas, A F; Leaderer, B; Bracken, M B

2001-07-01

264

Trisomy 21: from chromosomes to mental retardation.  

PubMed

The first descriptions of the trisomy 21 phenotype were by Jean-Etienne-Dominique Esquirol (1838), Edouard Séguin (1846) and later by John L. H. Down in 1862. It took more than a century to discover the extra-chromosomal origin of the syndrome commonly called "Down's syndrome" and which, we suggest, should be referred to as "Trisomy 21". In this review we are presenting the landmarks, from the pioneering description of the syndrome in 1838 to Jérôme Lejeune's discovery of the first genetic substrate for mental retardation. The sequencing of HSA21 was a new starting point that generated transcriptome studies, and we have noted that studies of gene over-expression have provided the impetus for discovering the HSA21 genes associated with trisomy 21 cognitive impairment. PMID:16596471

Roubertoux, Pierre L; Kerdelhué, Bernard

2006-05-01

265

Cytogenetic Findings in Mentally Retarded Iranian Patients  

PubMed Central

We conducted a cytogenetic study on 865 individuals with idiopathic mental retardation (MR) who were admitted to the Cytogenetics Department of the Iran Blood Transfusion Organisation (IBTO) Research Centre, Tehran, Iran; these were performed on blood samples using conventional staining methods. Chromosome anomalies were identified in 205 of the patients (23.6%). The majority were Down’s syndrome cases (n = 138). In 33 males, a positive fragile X anomaly was found. The remainder (n = 34) had other chromosomal abnormalities including structural chromosome aberrations (n = 23), marker chromosomes with an unknown origin (n = 3), sex chromosome aneuploidy (n = 6) and trisomy 18 (n = 2). The contribution of chromosome aberrations to the cause of MR in this group of patients is discussed. PMID:24052729

Nasiri, F; Mahjoubi, F; Manouchehry, F; Razazian, F; Mortezapour, F; Rahnama, M

2012-01-01

266

Emerging Brominated Flame Retardants in the Environment  

Microsoft Academic Search

\\u000a \\u000a Abstract  A number of new brominated flame retardants (BFRs) are being found in the environment but the amount of data is still very\\u000a small. The best studied emerging BFRs are 1,2-bis(2,4,6-tribromophenoxy)ethane and decabromodiphenyl ethane, with some data\\u000a for hexabromobenzene, pentabromoethylbenzene, pentabromotoluene, tetrabromobisphenol A derivatives, bis(2-ethylhexyl) tetrabromophthalate,\\u000a 2-ethylhexyltetrabromobenzoate, 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane, and 2,4,6-tribromophenol. Very little data are\\u000a available for 2,4,6-tribromophenyl allyl ether, 2,3-dibromopropyl-2,4,6-tribromophenyl ether,

Cynthia A. de Wit; Amelie Kierkegaard; Niklas Ricklund; Ulla Sellström

267

Topological dynamics of retarded functional differential equations  

NASA Astrophysics Data System (ADS)

We prove that a local flow can be constructed for a general class of nonautonomous retarded functional differential equations (RFDE). This is an extension to a result of Artstein (J. Differential Equations 23 (1977) 216) and fits in the classical theory of R. Miller and G. Sell. The main tool in this paper are generalized ordinary differential equations according to Kurzweil (Czech. Math. J. 7 (82) (1957) 418). In obtaining our results, we must prove the space of RFDEs can be embedded in a space of generalized ordinary differential equations. In opposition to the technical hypotheses of Oliva and Vorel (Bol. Soc. Mat. Mexicana 11 (1996) 40), this auxiliary result, as we present, is advantageous in the sense that our assumptions have an explanatory character. Applications based on topological dynamics techniques follow naturally from our results. As an illustration of this fact we show how to achieve in this setting a theorem on continuous dependence on initial data of solutions of RFDEs.

Federson, Márcia; Táboas, Plácido

268

Environmental monitoring of brominated flame retardants  

NASA Astrophysics Data System (ADS)

Brominated flame retardants (BFRs) are synthetic organobromide compounds which inhibit ignition and combustion processes. Because of their immense ability to retard fire and save life and property, they have been extensively used in many products such as TVs, computers, foam, plastics etc. The five major classes of BFRs are tetrabromobisphenol-A (TBBPA), hexabromocyclododecane (HBCD), pentabromodiphenyl ether, octabromodiphenyl ether, and decabromodiphenyl ether. The last three are also commonly called PBDEs. BDE-85 and BDE-209 are the two prominent congeners of PBDEs and this study reports the adverse effects of these congeners in rodents. Exposure of rat sciatic nerves to 5 ?g/mL and 20 ?g/mL of BDE-85 and BDE-209 respectively lead to significant, concentration dependent reduction in nerve conduction function. Glucose absorption in the rat intestinal segments exposed to 5 ?g/mL of BDE-85 and BDE-209 was significantly reduced for both the compounds tested. Lastly, mice when exposed to 0.25 mg/kg body weight for four days showed a disruption in oxidant and antioxidant equilibrium. The tissues namely liver and brain have shown increase in the levels of lipid hydroperoxides indicating oxidative stress. Moreover, all the protective enzymes namely superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, and glutathione S transferase (GST) have shown tissue specific alterations indicating the induction of damaging oxidative stress and setting in of lipid peroxidation in exposed animals. The results indicate monitoring of PBDEs in the environment is essential because levels as low as 5 ?g/mL and 0.25 mg/kg body weight were able to cause damage to the functions of rodents.

Vagula, Mary C.; Kubeldis, Nathan; Nelatury, Charles F.

2011-06-01

269

Evolution of developmental roles of Pax2/5/8 paralogs after independent duplication in urochordate and vertebrate lineages  

PubMed Central

Background Gene duplication provides opportunities for lineage diversification and evolution of developmental novelties. Duplicated genes generally either disappear by accumulation of mutations (nonfunctionalization), or are preserved either by the origin of positively selected functions in one or both duplicates (neofunctionalization), or by the partitioning of original gene subfunctions between the duplicates (subfunctionalization). The Pax2/5/8 family of important developmental regulators has undergone parallel expansion among chordate groups. After the divergence of urochordate and vertebrate lineages, two rounds of independent gene duplications resulted in the Pax2, Pax5, and Pax8 genes of most vertebrates (the sister group of the urochordates), and an additional duplication provided the pax2a and pax2b duplicates in teleost fish. Separate from the vertebrate genome expansions, a duplication also created two Pax2/5/8 genes in the common ancestor of ascidian and larvacean urochordates. Results To better understand mechanisms underlying the evolution of duplicated genes, we investigated, in the larvacean urochordate Oikopleura dioica, the embryonic gene expression patterns of Pax2/5/8 paralogs. We compared the larvacean and ascidian expression patterns to infer modular subfunctions present in the single pre-duplication Pax2/5/8 gene of stem urochordates, and we compared vertebrate and urochordate expression to infer the suite of Pax2/5/8 gene subfunctions in the common ancestor of olfactores (vertebrates + urochordates). Expression pattern differences of larvacean and ascidian Pax2/5/8 orthologs in the endostyle, pharynx and hindgut suggest that some ancestral gene functions have been partitioned differently to the duplicates in the two urochordate lineages. Novel expression in the larvacean heart may have resulted from the neofunctionalization of a Pax2/5/8 gene in the urochordates. Expression of larvacean Pax2/5/8 in the endostyle, in sites of epithelial remodeling, and in sensory tissues evokes like functions of Pax2, Pax5 and Pax8 in vertebrate embryos, and may indicate ancient origins for these functions in the chordate common ancestor. Conclusion Comparative analysis of expression patterns of chordate Pax2/5/8 duplicates, rooted on the single-copy Pax2/5/8 gene of amphioxus, whose lineage diverged basally among chordates, provides new insights into the evolution and development of the heart, thyroid, pharynx, stomodeum and placodes in chordates; supports the controversial conclusion that the atrial siphon of ascidians and the otic placode in vertebrates are homologous; and backs the notion that Pax2/5/8 functioned in ancestral chordates to engineer epithelial fusions and perforations, including gill slit openings. PMID:18721460

Bassham, Susan; Cañestro, Cristian; Postlethwait, John H

2008-01-01

270

Targeted germ line disruptions reveal general and species-specific roles for paralog group 1 hox genes in zebrafish  

PubMed Central

Background The developing vertebrate hindbrain is transiently segmented into rhombomeres by a process requiring Hox activity. Hox genes control specification of rhombomere fates, as well as the stereotypic differentiation of rhombomere-specific neuronal populations. Accordingly, germ line disruption of the paralog group 1 (PG1) Hox genes Hoxa1 and Hoxb1 causes defects in hindbrain segmentation and neuron formation in mice. However, antisense-mediated interference with zebrafish hoxb1a and hoxb1b (analogous to murine Hoxb1 and Hoxa1, respectively) produces phenotypes that are qualitatively and quantitatively distinct from those observed in the mouse. This suggests that PG1 Hox genes may have species-specific functions, or that anti-sense mediated interference may not completely inactivate Hox function in zebrafish. Results Using zinc finger and TALEN technologies, we disrupted hoxb1a and hoxb1b in the zebrafish germ line to establish mutant lines for each gene. We find that zebrafish hoxb1a germ line mutants have a more severe phenotype than reported for Hoxb1a antisense treatment. This phenotype is similar to that observed in Hoxb1 knock out mice, suggesting that Hoxb1/hoxb1a have the same function in both species. Zebrafish hoxb1b germ line mutants also have a more severe phenotype than reported for hoxb1b antisense treatment (e.g. in the effect on Mauthner neuron differentiation), but this phenotype differs from that observed in Hoxa1 knock out mice (e.g. in the specification of rhombomere 5 (r5) and r6), suggesting that Hoxa1/hoxb1b have species-specific activities. We also demonstrate that Hoxb1b regulates nucleosome organization at the hoxb1a promoter and that retinoic acid acts independently of hoxb1b to activate hoxb1a expression. Conclusions We generated several novel germ line mutants for zebrafish hoxb1a and hoxb1b. Our analyses indicate that Hoxb1 and hoxb1a have comparable functions in zebrafish and mouse, suggesting a conserved function for these genes. In contrast, while Hoxa1 and hoxb1b share functions in the formation of r3 and r4, they differ with regards to r5 and r6, where Hoxa1 appears to control formation of r5, but not r6, in the mouse, whereas hoxb1b regulates formation of r6, but not r5, in zebrafish. Lastly, our data reveal independent regulation of hoxb1a expression by retinoic acid and Hoxb1b in zebrafish. PMID:24902847

2014-01-01

271

Perceptual-Motor Attributes of Mentally Retarded Youth.  

ERIC Educational Resources Information Center

To evaluate six perceptual-motor attributes of trainable and educable mentally retarded children, a battery of tests was constructed which included body perception, gross agility, balance, locomotor ability, throwing, and tracking; 83 retarded subjects provided reliability data, and their scores, with those of 120 additional subjects, provided…

Cratty, Bryant J.

272

Mental Retardation. Selected Articles from the Rehabilitation Record.  

ERIC Educational Resources Information Center

Presented are six articles on residential living, vocational education, employment recreation, deinstitutionalization, and workshop experience of mentally retarded children and adults. K. Grunewald discusses the planning of housing for five- to eight person groups of retarded children and adults in varying kinds of residential facilities in Sweden…

Rehabilitation Services Administration (DHEW), Washington, DC.

273

Sex between People with "Mental Retardation": An Ethical Evaluation.  

ERIC Educational Resources Information Center

Discusses the issue of whether sex between mentally retarded individuals is morally permissable, and if so, under what conditions. Argues that mutual consent has unacceptable consequences for the mentally retarded. Specifies conditions where caregivers can grant permission for sexual activity. Describes the implications for future professionals'…

Spiecker, Ben; Steutel, Jan

2002-01-01

274

Effect of multiple reflections in retardation plates with elliptical birefringence  

NASA Astrophysics Data System (ADS)

The theory of elliptical retardation plates that takes into account a phenomenon of multiple reflections is presented. An analytical form of a transition matrix for a normally incident plane wave is shown. Sample calculations of phase shift introduced by quartz retardation plates and of the output-beam parameters as a function of plate thickness and optical axis orientation are done.

Pietraszkiewicz, Kazimierz; Wozniak, Wladyslaw A.; Kurzynowski, Piotr

1995-02-01

275

Serial Memory Span Thresholds of Normal and Mentally Retarded Children  

ERIC Educational Resources Information Center

Educable mental retardates and normal grade school students were presented seven classes of materials in both visual and auditory modalities for the determination of immediate memory span thresholds. Major conclusions included auditory presentation produces higher thresholds than visual, and retarded children may employ different processing…

Baumeister, Alfred A.

1974-01-01

276

Advantages of flame retardants based on nitrogen compounds  

Microsoft Academic Search

Nitrogen compounds are a small but rapidly growing group of flame retardants (FR) which are in the focus of public interest concerning environmentally friendly flame retardants. Today their main applications are melamine for polyurethane flexible foams, melamine cyanurate in nylons, melamine phosphates in polyolefines, melamine and melamine phosphates or dicyandiamide in intumescent paints, guanidine phosphates for textiles and guanidine sulfamate

H. Horacek; R. Grabner

1996-01-01

277

THE NEW AND MORE OPEN OUTLOOK FOR THE MENTALLY RETARDED.  

ERIC Educational Resources Information Center

THE PROCEEDINGS OF THIS 1965 WORKSHOP ON MENTAL RETARDATION ARE PRESENTED AS A COLLECTION OF NINE PAPERS AND SUMMARIES OF THREE SEMINAR DISCUSSIONS. IN THE INTRODUCTION, MAYNARD C. REYNOLDS DISCUSSES "THE NEW AND MORE OPEN OUTLOOK FOR THE MENTALLY RETARDED." OTHER PAPERS ARE (1) "THE IMPACT OF FEDERAL LEGISLATION ON DEVELOPMENT OF COMPREHENSIVE…

KELLY, ELIZABETH M.

278

Carbamazepine-Induced Hyponatremia in Patients with Mental Retardation.  

ERIC Educational Resources Information Center

This study of 40 patients with mental retardation receiving carbamazepine found hyponatremia in only 5 percent of these patients and found a statistically, but not clinically, significant decrease in serum sodium levels in patients receiving anticonvulsant polytherapy. Results support the use of this drug with patients with mental retardation and…

Kastner, Ted; And Others

1992-01-01

279

Intumescent Biobased-Polylactide Films to Flame Retard Nonwovens  

Microsoft Academic Search

The work focuses on the development of a new process to flame retard nonwovens, using films based on renewable resources. Films consist in intumescent formulations of polylactic acid (PLA), ammonium polyphosphate (APP) blended with lignin or starch and are coated on hemp or wool nonwovens. The objective of this study was to investigate the fire retardant and mechanical properties of

Christelle Reti; Mathilde Casetta; Sophie Duquesne; René Delobel; Jérémie Soulestin; Serge Bourbigot

280

RESEARCH IN SPEECH AND HEARING FOR MENTALLY RETARDED CHILDREN.  

ERIC Educational Resources Information Center

A REPORT OF A CONFERENCE ON RESEARCH IN SPEECH AND HEARING FOR MENTALLY RETARDED CHILDREN IS PRESENTED. THE MAIN AREAS INCLUDED ARE THEORETICAL APPROACHES TO LANGUAGE AND COMMUNICATION, PROCEDURES FOR MEASURING LANGUAGE, AND SPECIAL METHODS FOR TREATMENT. SPECIFIC REPORTS GIVEN ARE--"PSYCHOLINGUISTICS IN THE STUDY OF MENTAL RETARDATION" BY JOHN B.…

COPELAND, ROSS H.; SCHIEFELBUSCH, R.L.

281

Adaptive Behavior Malingering in Legal Claims of Mental Retardation  

ERIC Educational Resources Information Center

In 2002, the Supreme Court ruled that it is unconstitutional to put people with mental retardation to death for capital crimes ("Atkins v. Virginia," 2002). Justice Scalia dissented, suggesting that mental retardation is a condition easy to feign. The current study examined whether participants provided with the definition of mental…

Kadlubek, Renee Marie

2012-01-01

282

Communication Problems in Mental Retardation: Diagnosis and Management.  

ERIC Educational Resources Information Center

Discussed are the problems of communication in mental retardation with an introductory background and definition of this problem, including the etiological factors and general characteristics. A presentation of diagnostic methods leads into discussions of the problem of medical-dental management and educational management of the retarded child.…

Lillywhite, Herold S.; Bradley, Doris P.

283

Muscle Fatigue during Intermittent Exercise in Individuals with Mental Retardation  

ERIC Educational Resources Information Center

This study examined fatigue profile during intermittent exercise in 10 men with mild to moderate mental retardation (MR) and 10 men without mental retardation (C). They performed 4 x 30 s maximal knee extensions and flexions with 1-min rest on an isokinetic dynamometer. Peak torque of flexors (PTFL) and extensors (PTEX), total work (TW), and…

Zafeiridis, Andreas; Giagazoglou, Paraskevi; Dipla, Konstantina; Salonikidis, Konstantinos; Karra, Chrisanthi; Kellis, Eleftherios

2010-01-01

284

Complex aetiology of an apparently Mendelian form of Mental Retardation  

Microsoft Academic Search

BACKGROUND: Mental Retardation is a common heterogeneous neurodevelopment condition, which causes are still largely elusive. It has been suggested that half of the phenotypic variation of intelligence is explained by genetic variation. And genetic or inherited factors indeed account for most of the cases of mental retardation with an identifiable cause. However, only a few autosomal genes have been mapped

Ana Beleza-Meireles; Ingrid Kockum; Qiu-Ping Yuan; Simone Picelli; Lennart Wetterberg; Karl-Henrik Gustavson; Martin Schalling

2008-01-01

285

COGNITIVE TRAINING WITH RETARDED CHILDREN, I. FINAL REPORT.  

ERIC Educational Resources Information Center

THE MAJOR PURPOSE OF THIS RESEARCH WAS TO DETERMINE WHETHER TRAINING IN SPECIFIC COGNITIVE PROCESSES IS EFFECTIVE IN INCREASING THE COGNITIVE FUNCTIONING OF RETARDED CHILDREN. IN PHASE I OF THE PROJECT, 51 EDUCABLE RETARDED AND 18 NORMAL SUBJECTS RECEIVED A 20-DAY PROGRAM IN SIMILARITIES-DIFFERENCES CONCEPT FORMATION AND WERE COMPARED WITH 42…

CORTER, HAROLD M.; MCKINNEY, JAMES D.

286

Thoughts on the Police Interrogation of Individuals with Mental Retardation.  

ERIC Educational Resources Information Center

This article presents 20 reasons why it is usually easy for police to get confessions from individuals with mental retardation. It urges that police training be seen as everyone's responsibility and that individuals with mental retardation be prepared for possible police interrogation. (DB)

Perske, Robert

1994-01-01

287

TEACHING THE MENTALLY RETARDED, A HANDBOOK FOR WARD PERSONNEL.  

ERIC Educational Resources Information Center

WRITTEN FOR ATTENDANTS, VOLUNTEERS, PROFESSIONAL PEOPLE, AND PARENTS, THIS MANUAL PRESENTS PRINCIPLES AND METHODS FOR TEACHING THE MENTALLY RETARDED TO BE AS INDEPENDENT AS POSSIBLE. THE FIRST SECTION PROVIDES GENERAL INFORMATION ON THE DEVELOPMENTAL CHARACTERISTICS OF NORMAL CHILDREN AND CONTRASTS THESE WITH SOME OF THE NEEDS OF THE RETARDED.…

BENSBERG, GERALD J.

288

Mental Retardation, Families & Education in Bangladesh. Introduction & Bibliography.  

ERIC Educational Resources Information Center

This paper reviews the literature and presents a bibliography on the situation of people with mental retardation in Bangladesh. It begins with a review of the history of mental retardation in East Bengal, India (now Bangladesh) from the 1770s onwards but focuses on the development of disability information and formal services since the creation of…

Miles, M.

289

Recreation for the Mentally Retarded: A Handbook for Ward Personnel.  

ERIC Educational Resources Information Center

Designed primarily for use by ward personnel in residential facilities for the mentally retarded, the manual presents an overview of recreational services. Four papers introduce the importance of recreation and consider approaches for its provision: "Why Recreation?" (W. Lawler); "The Role of the Attendant in Providing Recreation for the Retarded"…

Southern Regional Education Board, Atlanta, GA.

290

Post High School Adjustment of the Educable Mentally Retarded.  

ERIC Educational Resources Information Center

Research was reviewed to determine factors which influence the adjustment of educable mentally retarded (EMR) persons after high school age. Study of family characteristics (home environment, ethnic differences, marriage) was said to indicate such conclusions as that physical conditions or location of the home have no bearing on the retardate's…

Vande Garde, Linda Chrisinger, Ed.

291

Crisis Intervention With the Mentally Retarded: The New Treatment Look.  

ERIC Educational Resources Information Center

The trend toward normalization of the mentally retarded has brought a new dimension to the problem of their adjustment. Within the past several years, large numbers of the mentally retarded have been discharged into the community from residential facilities; the stress and anxiety they experience at being thrust into a strange and alien world…

Sternlicht, Manny; Deutsch, Martin R.

292

A NEW GENERATION OF FLAME RETARDED POLYAMIDES BASED ON PHOSPHINATES  

Microsoft Academic Search

Polyamide 6 and 66, especially glass fibre reinforced grades, can be effectively fire retarded with a new halogen free product based on an organic phosphinic acid salt. Organic phosphinates are a newly developed class of flame retardants for engineering thermoplastics, and are especially effective for polyamides and polyesters. The chemical registration process in Europe (ELINCS) and US (TSCA) has already

S. Hörold; O. Schacker; W. Wanzke

293

IN VITRO DERMAL ABSORPTION OF FLAME RETARDANT CHEMICALS  

EPA Science Inventory

IN VITRO DERMAL ABSORPTION OF FLAME RETARDANT CHEMICALS. M F Hughes1, B C Edwards1, C T Mitchell1, and B Bhooshan2. 1US EPA, ORD, NHEERL, RTP, NC; 2US CPSC, LSC, Rockville, MD. Two flame retardant chemicals that are candidates for treating furniture fabrics were evaluated for ...

294

IN VITRO DERMAL ABSORPTION OF FLAME RETARDANT CHEMICALS  

EPA Science Inventory

ABSTRACT The use of flame retardant chemicals in furniture fabric could pose a potential health risk to consumers from dermal absorption of these compounds. The objective of this study was to examine the in vitro dermal absorption of two flame retardant chemicals, [14C]-d...

295

Retardation-induced plasmonic blinking in coupled nanoparticles  

E-print Network

Retardation-induced plasmonic blinking in coupled nanoparticles Holger Fischer* and Olivier J. F We study how retardation leads to interference effects in radiatively coupled plasmonic nanoparticles. We show that inclined illumination through a glass substrate on two plasmonic particles results

Floreano, Dario

296

Behind the Wheel Training for Individuals Labeled Moderately Retarded.  

ERIC Educational Resources Information Center

The study investigated a strategy for teaching two moderately retarded adults to perform skills required for driving an automobile. Training consisted of two phases--simulator training and driving-range training. Data supported the claim that moderately mentally retarded individuals are capable of performing complex behaviors. (SB)

Zider, Steven J.; Gold, Marc W.

1981-01-01

297

Newborn Screening To Prevent Mental Retardation. The Arc Q & A.  

ERIC Educational Resources Information Center

This information fact sheet on screening newborns to prevent mental retardation defines newborn screening and outlines how screening is performed. It discusses the six most common disorders resulting in mental retardation for which states most commonly screen. These include phenylketonuria, congenital hypothyroidism, galactosemia, maple syrup…

Arc, Arlington, TX.

298

MILD MENTAL RETARDATION--A GROWING CHALLENGE TO THE PHYSICIAN.  

ERIC Educational Resources Information Center

INTENDED FOR PHYSICIANS, THIS DOCUMENT DESCRIBES THE NATURE AND SCOPE OF THE PROBLEM OF MILD MENTAL RETARDATION, AND PRESENTS GUIDELINES FOR MEDICAL CARE AND COUNSELING OF MILDLY RETARDED CHILDREN AND THEIR FAMILIES. TWO GROUPS OF SUCH CHILDREN (BASED ON HIGH OR LOW SOCIOCULTURAL LEVEL) ARE EXAMINED AND CHARACTERIZED. THE TWO GROUPS ARE DISCUSSED…

Group for the Advancement of Psychiatry, Inc., New York, NY.

299

Programs for Preventing the Causes of Mental Retardation.  

ERIC Educational Resources Information Center

This monograph, which reports findings from the New Jersey Governor's Council on the Prevention of Mental Retardation, discusses the scope of mental retardation (MR), its causes, identification of people at risk, and prevention methods. The Council cites several cost-effective prevention programs, such as vaccination programs and prenatal care…

Oliphant, Peter S.; And Others

300

Arizona's Comprehensive Plan to Help the Mentally Retarded.  

ERIC Educational Resources Information Center

To help combat mental retardation, 136 recommendations are made for the following: establishment by statute of a division of mental retardation, an advisory council, and a coordinating council of agencies; changes in laws governing the Arizona Children's Colony, additional public school legislation, and a study of civil and criminal law; immediate…

Arizona State Dept. of Health, Phoenix. Mental Retardation Section.

301

Self-Instruction, Individual Differences, and Mental Retardation.  

ERIC Educational Resources Information Center

A general theoretical framework to guide research on self-instructional training was presented which suggests that the approach is particularly useful to young nonretarded children and mentally retarded persons. Retarded children taught to self-instruct show better attention, memory, and motivation and manifest less impulsive behavior, maladaptive…

Whitman, Thomas L.

1987-01-01

302

Juvenile polyposis with macrocephaly and mental retardation (? Ruvalcava-Myhre-Smith syndrome)--a case report.  

PubMed

A male child aged one and a half years with a history of rectal bleeding, on examination was found to have severe degree of anaemia with grade -III protein-energy-malnutrition and pneumonia. Colonoscopy revealed features of colonic polyposis. An upper gastro-intestinal endoscopy showed a duodenal polyp while barium meal follow-through did not reveal any polyps in the small intestine. Total colectomy and ileo-rectal anastomosis was done. Following histopathological study, the diagnosis of Juvenile polyposis syndrome was made, a very rare entity and is known to lead to adenocarcinoma of the gastrointestinal tract. In addition the child was found to have macrocephaly and mental retardation. The rarity and importance of the diagnosis of juvenile polyposis syndrome associated with macrocephaly and mental retardation (?Ruvalcava-Myhre-Smith syndrome) prompted the documentation of this case. PMID:16295443

Nandini, N M; Singh, Th Bipin; Kumar, Anil; Nandeesh

2004-07-01

303

314 American Association on Mental Retardation American Journal on Mental Retardation, 2001, Vol. 106, No. 4, 314326  

E-print Network

information well dur- ing encoding. For example, Spitz (1966) demonstrated that individuals with men- tal retardation recall more words when word lists are presented in a clustered fashion (e.g., all animals with men- tal retardation can recognize and utilize redundancy in digit strings, even when

Dennis, Nancy

304

The Effects of a Retarded Child's Social Initiations on the Behavior of Severely Retarded School-Aged Peers.  

ERIC Educational Resources Information Center

To increase the social responsiveness of two severely retarded and withdrawn children (six and ten years old), a five-year-old mildly retarded peer was trained to emit social approach behaviors using a procedure in which edible reinforcement was delivered by the trained peer contingent upon positive social response by the target subjects.…

Kerr, Mary Margaret; Young, Clifford C.

1979-01-01

305

76 FR 66750 - Certain Projectors With Controlled-Angle Optical Retarders, Components Thereof, and Products...  

Federal Register 2010, 2011, 2012, 2013

...Certain Projectors With Controlled-Angle Optical Retarders, Components Thereof...Re Certain Projectors with Controlled-Angle Optical Retarders, Components Thereof...of certain projectors with controlled-angle optical retarders, components...

2011-10-27

306

Siblings with chromosome mosaicism, microcephaly, and growth retardation: the phenotypic expression of a human mitotic mutant?  

Microsoft Academic Search

We report male and female siblings with extreme microcephaly and mental retardation, growth retardation, and multiple chromosome mosaicism. Mental retardation associated with chromosome mosaicism does not always carry a low recurrence risk.

J. L. Tolmie; E. Boyd; P. Batstone; M. E. Ferguson-Smith; L. Al Roomi; J. M. Connor

1988-01-01

307

16 CFR 1630.32 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2012 CFR

...rugs with fire-retardant treatment. 1630.32 Section 1630...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2012-01-01

308

16 CFR 1631.33 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2011 CFR

...rugs with fire-retardant treatment. 1631.33 Section 1631...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2011-01-01

309

16 CFR 1631.33 - Carpets and rugs with fire-retardant treatment.  

...rugs with fire-retardant treatment. 1631.33 Section 1631...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2014-01-01

310

16 CFR 1630.32 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2010 CFR

...rugs with fire-retardant treatment. 1630.32 Section 1630...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2010-01-01

311

16 CFR 1631.33 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2013 CFR

...rugs with fire-retardant treatment. 1631.33 Section 1631...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2013-01-01

312

16 CFR 1630.32 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2011 CFR

...rugs with fire-retardant treatment. 1630.32 Section 1630...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2011-01-01

313

16 CFR 1631.33 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2010 CFR

...rugs with fire-retardant treatment. 1631.33 Section 1631...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2010-01-01

314

16 CFR 1631.33 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2012 CFR

...rugs with fire-retardant treatment. 1631.33 Section 1631...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2012-01-01

315

16 CFR 1630.32 - Carpets and rugs with fire-retardant treatment.  

...rugs with fire-retardant treatment. 1630.32 Section 1630...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2014-01-01

316

16 CFR 1630.32 - Carpets and rugs with fire-retardant treatment.  

Code of Federal Regulations, 2013 CFR

...rugs with fire-retardant treatment. 1630.32 Section 1630...REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND...rugs with fire-retardant treatment. (a) For the purposes... (2) Fire-retardant treatment means...

2013-01-01

317

The zebrafish genome encodes the largest vertebrate repertoire of functional aquaporins with dual paralogy and substrate specificities similar to mammals  

Microsoft Academic Search

BACKGROUND: Aquaporins are integral membrane proteins that facilitate the transport of water and small solutes across cell membranes. These proteins are vital for maintaining water homeostasis in living organisms. In mammals, thirteen aquaporins (AQP0-12) have been characterized, but in lower vertebrates, such as fish, the diversity, structure and substrate specificity of these membrane channel proteins are largely unknown. RESULTS: The

Angèle Tingaud-Sequeira; Magdalena Calusinska; Roderick N Finn; François Chauvigné; Juanjo Lozano; Joan Cerdà

2010-01-01

318

Tetradecabromodiphenoxybenzene flame retardant undergoes photolytic debromination.  

PubMed

Highly brominated flame retardant compounds have relatively low bioavailability, but some of these compounds have been shown to be of environmental concern. Tetradecabromodiphenoxybenzene (TDBDPB) contains 14 bromine atoms and is the major component of commercial flame retardant mixtures such as the recently phased out SAYTEX 120. The chemical stability of TDBDPB has not been reported. We demonstrated that TDBDPB can photolytically undergo stepwise reductive debromination that follows first-order kinetic degradation models when exposed to UV or natural sunlight radiation and when dissolved in the solvents tetrahydrofuran, methanol, or n-hexane. Photolytic degradation half-lives of TDBDPB ranged from 98 to 169 min, 0.78 to 0.83 min, 1.0 to 1.8 min, and 4.9 to 7.4 min when exposed to UV-A, -B, and -C, and natural sunlight, respectively. However, the TDBDPB half-lives when exposed to UV-B and especially UV-C are likely underestimated since solutions were in borosilicate glass vials during irradiation resulting from increasingly lower % transmittance of ? < 300 nm. Neat technical TDBDPB powder exposed to UV-B and -C radiation also produced less brominated products, although the rate was much slower as compared to when in solution. Exposure of TDBDPB solutions to natural sunlight generated a number of polybrominated diphenoxybenzene (PBDPB) photolysis products, among which the Br(4)- to Br(7)-PBDPBs were the most frequently observed and estimated to be most concentrated. As evidenced by the TDBDPB half-lives and the degree of debrominated byproduct formation, the findings showed that the fraction of the absorbed irradiation that was of sufficient energy to break C-Br bonds of TDBDPB and lesser brominated PBDPBs increased from UV-B or -C to UV-A. Coincidentally, we recently reported on the presence of several Br(4) to Br(6) methoxylated PBDPBs in the Great Lakes herring gull eggs, which may be linked to a TDBDPB source via photolytic degradation to more bioavailable and persistent debromination products. PMID:23289781

Chen, Da; Letcher, Robert J; Gauthier, Lewis T; Chu, Shaogang

2013-02-01

319

Abnormalities of cell packing density and dendritic complexity in the MeCP2 A140V mouse model of Rett syndrome/X-linked mental retardation  

PubMed Central

Background Rett syndrome (RTT), a common cause of mental retardation in girls, is associated with mutations in the MECP2 gene. Most human cases of MECP2 mutation in girls result in classical or variant forms of RTT. When these same mutations occur in males, they often present as severe neonatal encephalopathy. However, some MECP2 mutations can also lead to diseases characterized as mental retardation syndromes, particularly in boys. One of these mutations, A140V, is a common, recurring missense mutation accounting for about 0.6% of all MeCP2 mutations and ranking 21st by frequency. It has been described in familial X-linked mental retardation (XLMR), PPM- X syndrome (Parkinsonism, Pyramidal signs, Macroorchidism, X-linked mental retardation) and in other neuropsychiatric syndromes. Interestingly, this mutation has been reported to preserve the methyl-CpG binding function of the MeCP2 protein while compromising its ability to bind to the mental retardation associated protein ATRX. Results We report the construction and initial characterization of a mouse model expressing the A140V MeCP2 mutation. These initial descriptive studies in male hemizygous mice have revealed brain abnormalities seen in both RTT and mental retardation. The abnormalities found include increases in cell packing density in the brain and a significant reduction in the complexity of neuronal dendritic branching. In contrast to some MeCP2 mutation mouse models, the A140V mouse has an apparently normal lifespan and normal weight gain patterns with no obvious seizures, tremors, breathing difficulties or kyphosis. Conclusion We have identified various neurological abnormalities in this mouse model of Rett syndrome/X-linked mental retardation which may help to elucidate the manner in which MECP2 mutations cause neuronal changes resulting in mental retardation without the confounding effects of seizures, chronic hypoventilation, or other Rett syndrome associated symptoms. PMID:20163734

2010-01-01

320

40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.  

Code of Federal Regulations, 2012 CFR

...measurement on receiving property of retarder and car coupling noise. 201.26 Section 201...measurement on receiving property of retarder and car coupling noise. (a) Retarders ...Ladj ave max ) for retarders. (b) Car coupling impact —(1)...

2012-07-01

321

40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.  

Code of Federal Regulations, 2010 CFR

...measurement on receiving property of retarder and car coupling noise. 201.26 Section 201...measurement on receiving property of retarder and car coupling noise. (a) Retarders ...Ladj ave max ) for retarders. (b) Car coupling impact —(1)...

2010-07-01

322

40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.  

...measurement on receiving property of retarder and car coupling noise. 201.26 Section 201...measurement on receiving property of retarder and car coupling noise. (a) Retarders ...Ladj ave max ) for retarders. (b) Car coupling impact —(1)...

2014-07-01

323

40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.  

Code of Federal Regulations, 2011 CFR

...measurement on receiving property of retarder and car coupling noise. 201.26 Section 201...measurement on receiving property of retarder and car coupling noise. (a) Retarders ...Ladj ave max ) for retarders. (b) Car coupling impact —(1)...

2011-07-01

324

40 CFR 201.26 - Procedures for the measurement on receiving property of retarder and car coupling noise.  

Code of Federal Regulations, 2013 CFR

...measurement on receiving property of retarder and car coupling noise. 201.26 Section 201...measurement on receiving property of retarder and car coupling noise. (a) Retarders ...Ladj ave max ) for retarders. (b) Car coupling impact —(1)...

2013-07-01

325

Adenosine Nucleotides and the Regulation of GRP94-Client Protein Interactions Meredith F. N. Rosser, Brian M. Trotta, Megan R. Marshall, Brent Berwin, and Christopher V. Nicchitta*,  

E-print Network

Da (GRP94), the endoplasmic reticulum Hsp90, is highly homologous to cytosolic Hsp90. However, neither-client protein complexes. GRP94,1 the endoplasmic reticulum (ER) Hsp90 paralog, serves an essential roleP) were isolated from myeloma cells, and the effects of adenosine nucleotides on chaperone-Ig heavy chain

Nicchitta, Chris

326

Brominated flame retardant exposure of aircraft personnel.  

PubMed

The use of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) in aircraft is the result of high fire safety demands. Personnel working in or with aircraft might therefore be exposed to several BFRs. Previous studies have reported PBDE exposure in flight attendants and in passengers. One other group that may be subjected to significant BFR exposure via inhalation, are the aircraft maintenance workers. Personnel exposure both during flights and maintenance of aircraft, are investigated in the present study. Several BFRs were present in air and dust sampled during both the exposure scenarios; PBDEs, hexabromocyclododecane (HBCDD), decabromodiphenyl ethane (DBDPE) and 1,2-bis (2,4,6-tribromophenoxy) ethane. PBDEs were also analyzed in serum from pilots/cabin crew, maintenance workers and from a control group of individuals without any occupational aircraft exposure. Significantly higher concentrations of PBDEs were found in maintenance workers compared to pilots/cabin crew and control subjects with median total PBDE concentrations of 19, 6.8 and 6.6pmolg(-1) lipids, respectively. Pilots and cabin crew had similar concentrations of most PBDEs as the control group, except for BDE-153 and BDE-154 which were significantly higher. Results indicate higher concentrations among some of the pilots compared to the cabin crew. It is however, evident that the cabin personnel have lower BFR exposures compared to maintenance workers that are exposed to such a degree that their blood levels are significantly different from the control group. PMID:24745557

Strid, Anna; Smedje, Greta; Athanassiadis, Ioannis; Lindgren, Torsten; Lundgren, Håkan; Jakobsson, Kristina; Bergman, Ake

2014-12-01

327

Synergistic effect between polyhedral oligomeric silsesquioxane and flame retardants  

NASA Astrophysics Data System (ADS)

Synergistic effect was observed between two types of flame retardant and two types of polyhedral oligomeric silsesquioxanes (POSS). The polymer matrix was represented by low density polyethylene Bralen RB 2-62 (Slovnaft). The polyethylene was mixed with nanofillers OctaIsobutyl POSS and TriSilanolIsobutyl POSS. The flame retardants was represented by ADK STAB® FP 2200 and Exolite® APP 722. The flammability was investigated by UL-94 test. The results showed that the APP/POSS system had important flame retardant and anti-dripping abilities for LDPE.

Safarikova, B.; Kalendova, A.; Habrova, V.; Zatloukalova, S.; Machovsky, M.

2014-05-01

328

Plant Growth Retardation and Conserved miRNAs Are Correlated to Hibiscus Chlorotic Ringspot Virus Infection  

PubMed Central

Virus infection may cause a multiplicity of symptoms in their host including discoloration, distortion and growth retardation. Hibiscus chlorotic ringspot virus (HCRSV) infection was studied using kenaf (Hibiscus cannabinus L.), a non-wood fiber-producing crop in this study. Infection by HCRSV reduced the fiber yield and concomitant economic value of kenaf. We investigated kenaf growth retardation and fluctuations of four selected miRNAs after HCRSV infection. Vegetative growth (including plant height, leaf size and root development) was severely retarded. From the transverse and radial sections of the mock and HCRSV-infected kenaf stem, the vascular bundles of HCRSV-infected plants were severely disrupted. In addition, four conserved plant developmental and defence related microRNAs (miRNAs) (miR165, miR167, miR168 and miR171) and their respective target genes phabulosa (PHB), auxin response factor 8 (ARF8), argonaute 1 (AGO1) and scarecrow-like protein 1 (SCL1) displayed variation in expression levels after HCRSV infection. Compared with the mock inoculated kenaf plants, miR171 and miR168 and their targets SCL1 and AGO1 showed greater fluctuations after HCRSV infection. As HCRSV upregulates plant SO transcript in kenaf and upregulated AGO1 in HCRSV-infected plants, the expression level of AGO1 transcript was further investigated under sulfite oxidase (SO) overexpression or silencing condition. Interestingly, the four selected miRNAs were also up- or down-regulated upon overexpression or silencing of SO. Plant growth retardation and fluctuation of four conserved miRNAs are correlated to HCRSV infection. PMID:24386476

Gao, Ruimin; Wan, Zi Yi; Wong, Sek-Man

2013-01-01

329

Plant growth retardation and conserved miRNAs are correlated to Hibiscus chlorotic ringspot virus infection.  

PubMed

Virus infection may cause a multiplicity of symptoms in their host including discoloration, distortion and growth retardation. Hibiscus chlorotic ringspot virus (HCRSV) infection was studied using kenaf (Hibiscus cannabinus L.), a non-wood fiber-producing crop in this study. Infection by HCRSV reduced the fiber yield and concomitant economic value of kenaf. We investigated kenaf growth retardation and fluctuations of four selected miRNAs after HCRSV infection. Vegetative growth (including plant height, leaf size and root development) was severely retarded. From the transverse and radial sections of the mock and HCRSV-infected kenaf stem, the vascular bundles of HCRSV-infected plants were severely disrupted. In addition, four conserved plant developmental and defence related microRNAs (miRNAs) (miR165, miR167, miR168 and miR171) and their respective target genes phabulosa (PHB), auxin response factor 8 (ARF8), argonaute 1 (AGO1) and scarecrow-like protein 1 (SCL1) displayed variation in expression levels after HCRSV infection. Compared with the mock inoculated kenaf plants, miR171 and miR168 and their targets SCL1 and AGO1 showed greater fluctuations after HCRSV infection. As HCRSV upregulates plant SO transcript in kenaf and upregulated AGO1 in HCRSV-infected plants, the expression level of AGO1 transcript was further investigated under sulfite oxidase (SO) overexpression or silencing condition. Interestingly, the four selected miRNAs were also up- or down-regulated upon overexpression or silencing of SO. Plant growth retardation and fluctuation of four conserved miRNAs are correlated to HCRSV infection. PMID:24386476

Gao, Ruimin; Wan, Zi Yi; Wong, Sek-Man

2013-01-01

330

Multiple Co-Evolutionary Networks Are Supported by the Common Tertiary Scaffold of the LacI/GalR Proteins  

PubMed Central

Protein families might evolve paralogous functions on their common tertiary scaffold in two ways. First, the locations of functionally-important sites might be “hard-wired” into the structure, with novel functions evolved by altering the amino acid (e.g. Ala vs Ser) at these positions. Alternatively, the tertiary scaffold might be adaptable, accommodating a unique set of functionally important sites for each paralogous function. To discriminate between these possibilities, we compared the set of functionally important sites in the six largest paralogous subfamilies of the LacI/GalR transcription repressor family. LacI/GalR paralogs share a common tertiary structure, but have low sequence identity (?30%), and regulate a variety of metabolic processes. Functionally important positions were identified by conservation and co-evolutionary sequence analyses. Results showed that conserved positions use a mixture of the “hard-wired” and “accommodating” scaffold frameworks, but that the co-evolution networks were highly dissimilar between any pair of subfamilies. Therefore, the tertiary structure can accommodate multiple networks of functionally important positions. This possibility should be included when designing and interpreting sequence analyses of other protein families. Software implementing conservation and co-evolution analyses is available at https://sourceforge.net/projects/coevolutils/. PMID:24391951

Parente, Daniel J.; Swint-Kruse, Liskin

2013-01-01

331

EFFECT OF ORGANOPHOSPHORUS FLAME RETARDANTS ON NEURONAL DEVELOPMENT IN VITRO  

EPA Science Inventory

The increased use of organophosphorus compounds as alternatives to brominated flame retardants (BFRs) has led to widespread human exposure, There is, however, limited information on their potential health effects. This study compared the effects of nii ne organophosphorus flame...

332

Cue Selection in Verbal Discrimination Learning of Retarded Subjects  

ERIC Educational Resources Information Center

Presents a series of these experiments which examined cue function in trigram verbal discrimination learning by retarded subjects. The two variables of chief interest were: (1) trigram meaningfulness, and (2) reinforcement history. (Author/LLK)

Ashford, Donnell C.; Baumeister, Alfred A.

1975-01-01

333

CRUSTED PILOLEIOMYOMA WITH MENTAL RETARDATION: A RARE ASSOCIATION  

PubMed Central

Piloleiomyoma is an uncommon benign smooth muscle neoplasm arising from arrector pili muscle. It is clinically defined by the presence of solitary or multiple reddish brown, dome-shaped, smooth papules or nodules, ranging in size from a few millimeters to a centimeter. The patients are otherwise healthy; but mental retardation developing in some patients with multiple Piloleiomyomas has been emerging as an intriguing matter for analysis by the scientists. In this case report, a mentally retarded patient with Piloleiomyoma is described, who, besides the characteristic smooth and dome-shaped lesions on the anterolateral aspect of the dorsum of the right foot, had developed crusting on one of the largest lesions. The histopathological features were consistent with Piloleiomyoma. The occurrence of Piloleiomyoma in a mentally retarded child and its unusual crusted nature has been rarely reported. The association between Piloleiomyoma and mental retardation is further stressed in this case report. PMID:20049278

Kamboj, Sangeeta; Sharma, Raj Kumar; Kumar, Amit; Chaudhary, Shyam Sundar; Jain, Vir Kumar

2009-01-01

334

Personal Vulnerability to Victimization of People with Mental Retardation  

Microsoft Academic Search

People with mental retardation are more vulnerable to victimization. This is a con- sequence of cultural, institutional, and other environmental circumstances but may include victim characteristics. To recognize this is not \\

TED NETTELBECK; CARLENE WILSON

2002-01-01

335

Clinical Comparison of Haloperidol with Chlorpromazine in Mentally Retarded Children  

ERIC Educational Resources Information Center

In an 8-week double-blind comparison, haloperidol reduced the severity of the target symptoms impulsiveness, hostility, and aggressiveness in significantly more mentally retarded children than did chlorpromazine. (Author)

LeVann, Leonard J.

1971-01-01

336

Aerobic Dance and the Mentally Retarded--A Winning Combination.  

ERIC Educational Resources Information Center

The results of a study on an experimental dance program for mentally retarded children show that these children can improve in physical fitness and that success through physical activities can enhance their generally poor self-concept. (JN)

Barton, Bonnie J.

1982-01-01

337

Music and the Mentally Retarded Ethnic Minority Child  

ERIC Educational Resources Information Center

Suggested are guidelines for the selection and use of music for the mentally retarded ethnic child who typically encounters language, social, and emotional problems and inferior educational opportunities. (CL)

Alford, Robert L.

1974-01-01

338

Burning To Learn: An Introduction to Flame Retardants.  

ERIC Educational Resources Information Center

Presents an activity that demonstrates the effectiveness of flame retardants--substances added to combustible materials to slow down or hinder burning--that can be introduced when discussing combustion reactions or during a practical or everyday chemistry unit. (ASK)

Journal of Chemical Education, 2001

2001-01-01

339

An Annotated Bibliography on the Severely and Profoundly Mentally Retarded.  

ERIC Educational Resources Information Center

Presented is an annotated bibliography with approximately 250 entries relating to the severely and profoundly retarded. Citations are listed alphabetically by author under the following categories: assessments, measurements, evaluations; associations; attending behavior; behavior modification; books; classical conditioning; cognitive development;…

Cass, Michael, Comp.; Schilit, Jeffrey, Comp.

340

Overexpression of MicroRNAs from the miR-17-92 Paralog Clusters in AIDS-Related Non-Hodgkin's Lymphomas  

PubMed Central

Background Individuals infected by HIV are at an increased risk for developing non-Hodgkin's lymphomas (AIDS-NHL). In the highly active antiretroviral therapy (HAART) era, there has been a significant decline in the incidence of AIDS-associated primary central nervous system lymphoma (PCNSL). However, only a modest decrease in incidence has been reported for other AIDS-NHL subtypes. Thus, AIDS-NHLs remain a significant cause of morbidity and mortality in HIV infected individuals. Recently, much attention has been directed toward the role of miRNAs in cancer, including NHL. Several miRNAs, including those encoded by the miR-17-92 polycistron, have been shown to play significant roles in B cell tumorigenesis. However, the role of miRNAs in NHL in the setting of HIV infection has not been defined. Methodology/Principal Findings We used quantitative realtime PCR to assess the expression of miRNAs from three different paralog clusters, miR-17-92, miR-106a-363, and miR-106b-25 in 24 cases of AIDS-NHLs representing four tumor types, Burkitt's lymphoma (BL, n?=?6), diffuse large B-cell lymphoma (DLBCL, n?=?8), primary central nervous system lymphoma (PCNSL, n?=?5), and primary effusion lymphoma (PEL, n?=?5). We also used microarray analysis to identify a differentiation specific miRNA signature of naïve, germinal center, and memory B cell subsets from tonsils (n?=?4). miRNAs from the miR-17-92 paralog clusters were upregulated by B cells, specifically during the GC differentiation stage. We also found overexpression of these miRNA clusters in all four AIDS-NHL subtypes. Finally, we also show that select miRNAs from these clusters (miR-17, miR-106a, and miR-106b) inhibited p21 in AIDS-BL and DLBCL cases, thus providing a mechanistic role for these miRNAs in AIDS-NHL pathogenesis. Conclusion Dysregulation of miR-17-92 paralog clusters is a common feature of AIDS-associated NHLs. PMID:21698185

Thapa, Dharma R.; Li, Xinmin; Jamieson, Beth D.; Martinez-Maza, Otoniel

2011-01-01

341

Flame retardancy of paulownia wood and its mechanism  

Microsoft Academic Search

Paulownia wood (Pauloumia tomentosa) is a special kind of wood material in that it has especially excellent flame retardancy.\\u000a Using this property, it has been commonly used to make clothing wardrobes for a long time in Japan. In this research, the\\u000a flame retardancy of paulownia wood has been verified by heating experiments and cone calorimeter testing. The structure and\\u000a tissue

Peng Li; Juhachi Oda

2007-01-01

342

Ignition inhibitors for cellulosic materials. [Fire retardants; effects of irradiation  

Microsoft Academic Search

By exposing samples to various irradiance levels from a calibrated thermal radiation source, the ignition responses of blackened alpha-cellulose and cotton cloth with and without fire-retardant additives were compared. Samples treated with retardant compounds which showed the most promise were then isothermally pyrolyzed in air for comparisons between the pyrolysis rates. Alpha-cellulose samples containing a mixture of boric acid, borax,

Alvares

1976-01-01

343

Combustion of brominated flame retardants and behavior of its byproducts  

Microsoft Academic Search

The substance flow rate of PBDDs\\/DFs into flue gas and incineration residues from incineration of three types of waste samples containing brominated flame retardants were examined. The samples used consisted of PBDEs (a typical retardant), used TV casing materials (actual waste materials), and waste printed circuit boards. PBDDs\\/DFs concentrations in the experimental samples of PBDEs\\/PE, waste TV casing materials and

Shin-ichi Sakai; Jun Watanabe; Yoshiharu Honda; Hiroshi Takatsuki; Isamu Aoki; Masayuki Futamatsu; Ken Shiozaki

2001-01-01

344

In vitro dermal absorption of flame retardant chemicals  

Microsoft Academic Search

Flame retardant chemicals may be used in furniture fabric in the future to reduce the flammability of the fabric. As a part of the process to evaluate the potential for exposure to these chemicals, this study examined the in vitro dermal absorption of two flame retardant chemicals. The chemicals were [14C]decabromodiphenyl oxide (DBDPO) and [14C]tris-(1,3-dichloro-2-propyl)phosphate (TDCP). Skin from the adult

M. F Hughes; B. C Edwards; C. T Mitchell; B Bhooshan

2001-01-01

345

Flame retardant exposure among collegiate United States gymnasts.  

PubMed

Gymnastics training facilities contain large volumes of polyurethane foam, a material that often contains additive flame retardants such as PentaBDE. While investigations of human exposure to flame retardants have focused on the general population, potentially higher than background exposures may occur in gymnasts and certain occupational groups. Our objectives were to compare PentaBDE body burden among gymnasts to the general United States population and characterize flame retardants levels in gym equipment, air, and dust. We recruited 11 collegiate female gymnasts (ages 18-22) from one gym in the eastern United States. The geometric mean (GM) concentration of BDE-153 in gymnast sera (32.5 ng/g lipid) was 4-6.5 times higher than in the general United States population groups. Median concentrations of PentaBDE, TBB, and TBPH in paired handwipe samples were 2-3 times higher after practice compared to before, indicating the gymnasts contacted these flame retardants during practice. GM concentrations of PentaBDE, TBB, and TBPH were 1-3 orders of magnitude higher in gym air and dust than in residences. Our findings suggest that these collegiate gymnasts experienced higher exposures to PentaBDE flame retardants compared to the general United States population and that gymnasts may also have increased exposure to other additive flame retardants used in polyurethane foam such as TBB and TBPH. PMID:24195753

Carignan, Courtney C; Heiger-Bernays, Wendy; McClean, Michael D; Roberts, Simon C; Stapleton, Heather M; Sjödin, Andreas; Webster, Thomas F

2013-12-01

346

New Thoughts on Play and Leisure Activities for Children and Adults Who Are Mentally Retarded.  

ERIC Educational Resources Information Center

Surveys on leisure and recreational patterns of mentally retarded individuals were completed by 98 parents of retarded children and adults. Results are reported, along with reviews of the literature in three general headings: (1) play in mentally retarded children under 12; (2) leisure and recreation activities in mentally retarded individuals 12…

Hughes, Selma; Fullwood, Harry L.

347

Effects of nanoclay and fire retardants on fire retardancy of a polymer blend of EVA and LDPE  

Microsoft Academic Search

The effects of nanoclay (organoclay) and fire retardants (aluminium tri-hydroxide and magnesium hydroxide) on the fire retardancy of a polymer blend of ethylene-vinyl acetate (EVA) and low-density polyethylene (LDPE) were assessed using thermogravimetric analysis (TGA) and the cone calorimeter. TGA measurements were conducted in nitrogen and air atmospheres at different heating rates (1–20°C\\/min), whilst in the cone calorimeter square samples

J. Zhang; J. Hereid; M. Hagen; D. Bakirtzis; M. A. Delichatsios; A. Fina; A. Castrovinci; G. Camino; F. Samyn; S. Bourbigot

2009-01-01

348

Measurement errors resulted from misalignment errors of the retarder in a rotating-retarder complete Stokes polarimeter.  

PubMed

Rotatable retarder fixed polarizer (RRFP) Stokes polarimeters, which employ uniformly spaced angles over 180° or 360°, are most commonly used to detect the state of polarization (SOP) of an electromagnetic (EM) wave. The misalignment error of the retarder is one of the major error sources. We suppose that the misalignment errors of the retarder obey a uniform normal distribution and are independent of each other. Then, we derive analytically the covariance matrices of the measurement errors. Based on the covariance matrices derived, we can conclude that 1) the measurement errors are independent of the incident intensity s0, but seriously depend on the Stokes parameters (s1, s2, s3) and the retardance of the retarder ?; 2) for any mean incident SOP, the optimal initial angle and retardance to minimize the measurement error both can be achieved; 3) when N = 5, 10, 12, the initial orienting angle could be used as an added degree of freedom to strengthen the immunity of RRFP Stokes polarimeters to the misalignment error. Finally, a series of simulations are performed to verify these theoretical results. PMID:24921308

Dai, Hu; Yan, Changxiang

2014-05-19

349

All Dact (Dapper/Frodo) scaffold proteins dimerize and exhibit conserved interactions with Vangl, Dvl, and serine/threonine kinases  

PubMed Central

Background The Dact family of scaffold proteins was discovered by virtue of binding to Dvl proteins central to Wnt and Planar Cell Polarity (PCP) signaling. Subsequently Dact proteins have been linked to a growing list of potential partners implicated in ?-catenin-dependent and ?-catenin-independent forms of Wnt and other signaling. To clarify conserved and non-conserved roles for this protein family, we systematically compared molecular interactions of all three murine Dact paralogs by co-immunoprecipitation of proteins recombinantly expressed in cultured human embryonic kidney cells. Results Every Dact paralog readily formed complexes with the Vangl, Dvl, and CK1?/? proteins of species ranging from fruit flies to humans, as well as with PKA and PKC. Dact proteins also formed complexes with themselves and with each other; their conserved N-terminal leucine-zipper domains, which have no known binding partners, were necessary and sufficient for this interaction, suggesting that it reflects leucine-zipper-mediated homo- and hetero-dimerization. We also found weaker, though conserved, interactions of all three Dact paralogs with the catenin superfamily member p120ctn. Complex formation with other previously proposed partners including most other catenins, GSK3, LEF/TCF, HDAC1, and TGF? receptors was paralog-specific, comparatively weak, and/or more sensitive to empirical conditions. Conclusions Combined with published functional evidence from targeted knock-out mice, these data support a conserved role for Dact proteins in kinase-regulated biochemistry involving Vangl and Dvl. This strongly suggests that a principal role for all Dact family members is in the PCP pathway or a molecularly related signaling cascade in vertebrates. PMID:21718540

2011-01-01

350

CA8 Mutations Cause a Novel Syndrome Characterized by Ataxia and Mild Mental Retardation with Predisposition to Quadrupedal Gait  

Microsoft Academic Search

We describe a consanguineous Iraqi family in which affected siblings had mild mental retardation and congenital ataxia characterized by quadrupedal gait. Genome-wide linkage analysis identified a 5.8 Mb interval on chromosome 8q with shared homozygosity among the affected persons. Sequencing of genes contained in the interval revealed a homozygous mutation, S100P, in carbonic anhydrase related protein 8 (CA8), which is

Seval Türkmen; Gao Guo; Masoud Garshasbi; Katrin Hoffmann; Amjad J. Alshalah; Claudia Mischung; Andreas Kuss; Nicholas Humphrey; Stefan Mundlos; Peter N. Robinson

2009-01-01

351

The Protein Chaperone HSP90 Can Facilitate the Divergence of Gene Duplicates  

PubMed Central

The heat-shock protein 90 (HSP90) acts as a chaperone by ensuring proper maturation and folding of its client proteins. The HSP90 capacitor hypothesis holds that interactions with HSP90 allow proteins to accumulate mutations while maintaining function. Following this logic, HSP90 clients would be predicted to show relaxed selection compared with nonclients. In this study, we identify a new HSP90 client in the plant steroid hormone pathway: the transcription factor BES1. Its closest paralog, BZR1, is not an HSP90 client. This difference in HSP90 client status in two highly similar proteins enabled a direct test of the capacitor hypothesis. We find that BES1 shows relaxed selection compared to BZR1, hallmarks of neo- and subfunctionalization, and dynamic HSP90 client status across independent evolutionary paths. These results suggested that HSP90’s influence on gene evolution may be detectable if we compare gene duplicates because duplicates share most other properties influencing evolutionary rate that might otherwise conceal the chaperone’s effect. We test this hypothesis using systematically identified HSP90 clients in yeast and observe a significant trend of HSP90 clients evolving faster than their nonclient paralogs. This trend was not detected when yeast clients and nonclients were compared without considering paralog status. Our data provide evidence that HSP90 influences selection on genes encoding its clients and facilitates divergence between gene duplicates. PMID:23410833

Lachowiec, Jennifer; Lemus, Tzitziki; Thomas, James H.; Murphy, Patrick J. M.; Nemhauser, Jennifer L.; Queitsch, Christine

2013-01-01

352

Comparative Genomics of Helicobacter pylori: Analysis of the Outer Membrane Protein Families  

PubMed Central

The two complete genomic sequences of Helicobacter pylori J99 and 26695 were used to compare the paralogous families (related genes within one genome, likely to have related function) of genes predicted to encode outer membrane proteins which were present in each strain. We identified five paralogous gene families ranging in size from 3 to 33 members; two of these families contained members specific for either H. pylori J99 or H. pylori 26695. Most orthologous protein pairs (equivalent genes between two genomes, same function) shared considerable identity between the two strains. The unusual set of outer membrane proteins and the specialized outer membrane may be a reflection of the adaptation of H. pylori to the unique gastric environment where it is found. One subfamily of proteins, which contains both channel-forming and adhesin molecules, is extremely highly related at the sequence level and has likely arisen due to ancestral gene duplication. In addition, the largest paralogous family contained two essentially identical pairs of genes in both strains. The presence and genomic organization of these two pairs of duplicated genes were analyzed in a panel of independent H. pylori isolates. While one pair was present in every strain examined, one allele of the other pair appeared partially deleted in several isolates. PMID:10858232

Alm, Richard A.; Bina, James; Andrews, Beth M.; Doig, Peter; Hancock, Robert E. W.; Trust, Trevor J.

2000-01-01

353

Current Issues in Mental Retardation and Human Development: Selected Papers from the 1970 Staff Development Conferences of the President's Committee on Mental Retardation (Washington, D.C., 1971).  

ERIC Educational Resources Information Center

Six papers discuss some of the current issues in the field of mental retardation and human development. Epidemiology of mental retardation from a sociological and clinical point of view is analyzed by Jane R. Mercer, based on studies of mental retardation in the community in Pomona, California. The role of genetics and intra-uterine diagnosis of…

Stedman, Donald J., Ed.

354

CHD5, a brain-specific paralog of Mi2 chromatin remodeling enzymes, regulates expression of neuronal genes.  

PubMed

CHD5 is frequently deleted in neuroblastoma and is a tumor suppressor gene. However, little is known about the role of CHD5 other than it is homologous to chromatin remodeling ATPases. We found CHD5 mRNA was restricted to the brain; by contrast, most remodeling ATPases were broadly expressed. CHD5 protein isolated from mouse brain was associated with HDAC2, p66ß, MTA3 and RbAp46 in a megadalton complex. CHD5 protein was detected in several rat brain regions and appeared to be enriched in neurons. CHD5 protein was predominantly nuclear in primary rat neurons and brain sections. Microarray analysis revealed genes that were upregulated and downregulated when CHD5 was depleted from primary neurons. CHD5 depletion altered expression of neuronal genes, transcription factors, and brain-specific subunits of the SWI/SNF remodeling enzyme. Expression of gene sets linked to aging and Alzheimer's disease were strongly altered by CHD5 depletion from primary neurons. Chromatin immunoprecipitation revealed CHD5 bound to these genes, suggesting the regulation was direct. Together, these results indicate that CHD5 protein is found in a NuRD-like multi-protein complex. CHD5 expression is restricted to the brain, unlike the closely related family members CHD3 and CHD4. CHD5 regulates expression of neuronal genes, cell cycle genes and remodeling genes. CHD5 is linked to regulation of genes implicated in aging and Alzheimer's disease. PMID:21931736

Potts, Rebecca Casaday; Zhang, Peisu; Wurster, Andrea L; Precht, Patricia; Mughal, Mohamed R; Wood, William H; Zhang, Yonqing; Becker, Kevin G; Mattson, Mark P; Pazin, Michael J

2011-01-01

355

Exposure to flame retardant chemicals on commercial airplanes  

PubMed Central

Background Flame retardant chemicals are used in materials on airplanes to slow the propagation of fire. These chemicals migrate from their source products and can be found in the dust of airplanes, creating the potential for exposure. Methods To characterize exposure to flame retardant chemicals in airplane dust, we collected dust samples from locations inside 19 commercial airplanes parked overnight at airport gates. In addition, hand-wipe samples were also collected from 9 flight attendants and 1 passenger who had just taken a cross-country (USA) flight. The samples were analyzed for a suite of flame retardant chemicals. To identify the possible sources for the brominated flame retardants, we used a portable XRF analyzer to quantify bromine concentrations in materials inside the airplanes. Results A wide range of flame retardant compounds were detected in 100% of the dust samples collected from airplanes, including BDEs 47, 99, 153, 183 and 209, tris(1,3-dichloro-isopropyl)phosphate (TDCPP), hexabromocyclododecane (HBCD) and bis-(2-ethylhexyl)-tetrabromo-phthalate (TBPH). Airplane dust contained elevated concentrations of BDE 209 (GM: 500 ug/g; range: 2,600 ug/g) relative to other indoor environments, such as residential and commercial buildings, and the hands of participants after a cross-country flight contained elevated BDE 209 concentrations relative to the general population. TDCPP, a known carcinogen that was removed from use in children’s pajamas in the 1970’s although still used today in other consumer products, was detected on 100% of airplanes in concentrations similar to those found in residential and commercial locations. Conclusion This study adds to the limited body of knowledge regarding exposure to flame retardants on commercial aircraft, an environment long hypothesized to be at risk for maximum exposures due to strict flame retardant standards for aircraft materials. Our findings indicate that flame retardants are widely used in many airplane components and all airplane types, as expected. Most flame retardants, including TDCPP, were detected in 100% of dust samples collected from the airplanes. The concentrations of BDE 209 were elevated by orders of magnitude relative to residential and office environments. PMID:23413926

2013-01-01

356

A Polycarbonate/Magnesium Oxide Nanocomposite with High Flame Retardancy  

PubMed Central

A new flame retardant polycarbonate/magnesium oxide (PC/MgO) nanocomposite, with high flame retardancy was developed by melt compounding. The effect of MgO to the flame retardancy, thermal property, and thermal degradation kinetics were investigated. Limited oxygen index (LOI) test revealed that a little amount of MgO (2 wt %) led to significant enhancement (LOI = 36.8) in flame retardancy. Thermogravimetric analysis results demonstrated that the onset temperature of degradation and temperature of maximum degradation rate decreased in both air and N2 atmosphere. Apparent activation energy was estimated via Flynn–Wall–Ozawa method. Three steps in the thermal degradation kinetics were observed after incorporation of MgO into the matrix and the additive raised activation energies of the composite in the full range except the initial stage. It was interpreted that the flame retardancy of PC was influenced by MgO through the following two aspects: on the one hand, MgO catalyzed the thermal-oxidative degradation and accelerated a thermal protection/mass loss barrier at burning surface; on the other hand, the filler decreased activation energies in the initial step and improved thermal stability in the final period. PMID:24696526

Dong, Quanxiao; Gao, Chong; Ding, Yanfen; Wang, Feng; Wen, Bin; Zhang, Shimin; Wang, Tongxin; Yang, Mingshu

2014-01-01

357

The clinical profile of mentally retarded children in India and prevalence of depression in mothers of the mentally retarded  

PubMed Central

Background: Mental retardation (MR) has a varied phenomenology in different parts of the world. While studying MR, psychological issues of caretakers are equally relevant. A study to investigate the phenomenology of MR in Indian children and the prevalence of depression in their mothers was planned in a teaching institute in Madhya Pradesh with an attached tertiary care hospital. Objectives: The objective of the following study is to study the clinical profile of mentally retarded children in the study sample, prevalence of depression in the mothers and investigate various factors affecting it. Study Design: A cross-sectional study. Materials and Methods: A total of 60 patients diagnosed as MR were included in the study. Objective data was collected in a special proforma and mothers of these individuals were subjected to evaluation with Beck's Anxiety Inventory and the 17 item Hamilton Rating Scale for Depression. Results: The mean age of patients in the sample was 11.6 years, had received an average of 2.42 years of schooling, mean age at diagnosis of MR was 6.5 years and their mean IQ was 53. Out of the total 60 patients, 88% of the patients had significant co-morbidities. The prevalence of depression in mothers was 85% and it was more in mothers of, the ones with significant co-morbidities (OR = 2.67), severer forms of retardation and with higher levels of anxiety in the mother. Conclusions: Prevalence of depression in mothers of mentally retarded children in India seems to be much greater than those reported from studies around the world. Medical services offered to the mentally retarded should move from an individual level to the family level, especially toward the mothers, who are the main caretakers. Counseling services, treatment if required and regular screening of mothers of the mentally retarded should be included in the protocol for management of mental retardation. PMID:24891705

Nagarkar, Amit; Sharma, Jagdish Prashad; Tandon, S. K.; Goutam, Pritesh

2014-01-01

358

Beyond Reason: The Death Penalty and Offenders with Mental Retardation  

NSDL National Science Digital Library

Released by Human Rights Watch, this report examines the recent history of capital punishment of mentally retarded offenders in the United States, offering "the first comprehensive human rights-based analysis of such executions." The report reveals that 25 US states still permit the execution of offenders with mental retardation and that at least 35 such offenders have been executed since 1976. The report explores the topics of mental retardation, legal standards, and criminal culpability, and tells the stories of sixteen individuals "who have been sentenced to death despite the profound intellectual limitations they have suffered since birth." The 50-page report may be read by chapter in HTML format at the Human Rights Watch site.

2001-01-01

359

Polarimetric stellar interferometry by use of birefringent retarders.  

PubMed

We propose a polarimetric technique for a stellar interferometer that uses two birefringent retarders inserted into each arm of the interferometer. The retarders shift the interference fringes of the two orthogonal polarizations to opposite directions along an optical path difference (OPD), which enables us to measure the polarized fringe visibilities separately. Laboratory demonstrations were carried out using quartz retarders with a thickness of 1.124 mm, and the separation of the interferometric fringes of +/-10 microm along the OPD was observed. We discuss a calibration method for the acquired fringes to obtain reliable estimations of polarized fringe visibilities. We also discuss feasibility of the proposed technique for the Mitaka optical InfraRed Array (MIRA-I.2). PMID:19844314

Murakami, Naoshi; Ohishi, Naoko; Nishikawa, Jun; Yoshizawa, Masanori

2009-10-20

360

Zinc-Responsive Regulation of Alternative Ribosomal Protein Genes in Streptomyces coelicolor Involves Zur and  R  

Microsoft Academic Search

Streptomyces coelicolor contains paralogous versions of seven ribosomal proteins (S14, S18, L28, L31, L32, L33, and L36), which differ in their potential to bind structural zinc. The paralogues are termed C or C on the basis of the presence or absence of putative cysteine ligands. Here, mutational studies suggest that the C version of L31 can functionally replace its C

Gillian A. Owen; Ben Pascoe; Dimitris Kallifidas; Mark S. B. Paget

2007-01-01

361

Organophosphate Ester Flame Retardant-Induced Acute Intoxications in Dogs  

Microsoft Academic Search

Introduction  Flame retardants have wide industrial applications and are incorporated into articles found in automobiles and home environments,\\u000a including seat cushions. These compounds differ widely chemically and in their toxic potential. We report here two cases involving\\u000a dogs following ingestion of car seat cushions impregnated with organophosphate ester fire retardants.\\u000a \\u000a \\u000a \\u000a \\u000a Case Reports  Two case reports are presented. Two adult American Pit Bull

Andreas F. Lehner; Francisca Samsing; Wilson K. Rumbeiha

2010-01-01

362

Identifying some high risk populations for mental retardation  

E-print Network

subjects from the inst1tu- tionalized group and 45 subjects from the community based group, Information taken from the records of the subjects was birth order, the age of the subject's mother at the time of the mentally retarded child 's bi rth, race... born children while those in the community based group were first born children. As predicted the race of an ind1vidual alone had no bearing on his risk of being mentally retarded. Also it was concluded that the mother's age was no predictor...

Duesterhoft, Kenneth Wayne

2012-06-07

363

Fire-Retardant Decorative Inks For Aircraft Interiors  

NASA Technical Reports Server (NTRS)

Report describes testing of commercial and experimental fire retardants for incorporation into acrylic printing inks used on aircraft-interior sandwich panels. Films of acrylic ink containing fire-retardant additives prepared by casting on glass plates. Solvent evaporated in vacuum, cast films cured at 80 to 100 degree C for 30 minutes in air-circulating oven. Thermochemical properties of films examined by thermogravimetric analysis and differential scanning calorimetry (DSC). Samples of inks cast on sheets of polyvinylfloride (PVF), and their limiting oxygen indices and smoke evolution measured.

Kourtides, D. A.; Nir, Z.; Mikroyannidis, J. A.

1988-01-01

364

A retarding ion mass spectrometer for the Dynamics Explorer-1  

NASA Technical Reports Server (NTRS)

The Retarding Ion Mass Spectrometer (RIMS) for Dynamics Explorer-1 is an instrument designed to measure the details of the thermal plasma distribution. It combines the ion temperature determining capability of the retarding potential analyzer with the compositional capabilities of the mass spectrometer and adds multiple sensor heads to sample all directions relative to the spacecraft ram direction. This manual provides a functional description of the RIMS, the instrument calibration, and a description of the commands which can be stored in the instrument logic to control its operation.

Wright, W.

1985-01-01

365

A prokaryotic superoxide dismutase paralog lacking two Cu ligands: from largely unstructured in solution to ordered in the crystal.  

PubMed

Little is known about prokaryotic homologs of Cu,Zn superoxide dismutase (SOD), an enzyme highly conserved among eukaryotic species. In 138 Archaea and Bacteria genomes, 57 of these putative homologs were found, 11 of which lack at least one of the metal ligands. Both the solution and the crystal structures of the SOD-like protein from Bacillus subtilis, lacking two Cu ligands and found to be enzymatically inactive, were determined. In solution, the protein is monomeric. The available nuclear Overhauser effects, together with chemical-shift index values, allowed us to define and to recognize the typical Cu,Zn SOD Greek beta-barrel but with largely unstructured loops (which, therefore, sample a wide range of conformations). On the contrary, in the crystal structure (obtained in the presence of slight excess of Zn), the protein is well structured and organized in covalent dimers held by a symmetric bridge consisting of a Zn ion bound to an Asp-His dyad in a tetrahedral geometry. Couples of dimers held by hydrophobic interactions and H bonds are further organized in long chains. The order/disorder transition is discussed in terms of metal binding and physical state. PMID:15897454

Banci, Lucia; Bertini, Ivano; Calderone, Vito; Cramaro, Fiorenza; Del Conte, Rebecca; Fantoni, Adele; Mangani, Stefano; Quattrone, Alessandro; Viezzoli, Maria Silvia

2005-05-24

366

Loss-of-function variation in the DPP6 gene is associated with autosomal dominant microcephaly and mental retardation.  

PubMed

The molecular basis of autosomal dominant microcephaly, a disorder associated with small head circumferences that results in variable mental retardation, is largely unknown. In the present study, we conducted a variation analysis of the DPP6 gene in patients with autosomal dominant microcephaly and variable mental retardation. The copy number variation analysis of DPP6 was performed on DNA samples from 22 patients with microcephaly using high-resolution, array-based genomic hybridization, and sequence analysis was performed to screen mutations in another 50 microcephalic patients. Two de novo deletions and one missense mutation in familial microcephalic patients were identified. The transfection of plasmids encoding green fluorescent protein-pLLU2G-shDPP6 fusion proteins in mouse brains revealed that the decreased expression of the DPP6 gene slightly reduced the weight of the mouse brains and resulted in mouse learning disabilities compared with their wild-type littermates. Our data indicate that the loss-of-function variations in DPP6 are associated with autosomal dominant microcephaly and mental retardation. DPP6 appears to play a major role in the regulation of proliferation and migration of neurons in neurogenesis, most likely by participating in neuronal electrical excitability, synaptic integration, and plasticity. PMID:23832105

Liao, Can; Fu, Fang; Li, Ru; Yang, Wen-Qing; Liao, Hua-Yi; Yan, Jia-Rong; Li, Jian; Li, Shi-Yuan; Yang, Xin; Li, Dong-Zhi

2013-09-01

367

MECP2 is highly mutated in X-linked mental retardation.  

PubMed

Following the recent discovery that the methyl-CpG binding protein 2 (MECP2) gene located on Xq28 is involved in Rett syndrome (RTT), a wild spectrum of phenotypes, including mental handicap, has been shown to be associated with mutations in MECP2. These findings, with the compelling genetic evidence suggesting the presence in Xq28 of additional genes besides RabGDI1 and FMR2 involved in non-specific X-linked mental retardation (MRX), prompted us to investigate MECP2 in MRX families. Two novel mutations, not found in RTT, were identified. The first mutation, an E137G, was identified in the MRX16 family, and the second, R167W, was identified in a new mental retardation (MR) family shown to be linked to Xq28. In view of these data, we screened MECP2 in a cohort of 185 patients found negative for the expansions across the FRAXA CGG repeat and reported the identification of mutations in four sporadic cases of MR. One of the mutations, A140V, which we found in two patients, has been described previously, whereas the two others, P399L and R453Q, are novel mutations. In addition to the results demonstrating the involvement of MECP2 in MRX, this study shows that the frequency of mutations in MECP2 in the mentally retarded population screened for the fragile X syndrome is comparable to the frequency of the CGG expansions in FMR1. Therefore, implementation of systematic screening of MECP2 in MR patients should result in significant progress in the field of molecular diagnosis and genetic counseling of mental handicap. PMID:11309367

Couvert, P; Bienvenu, T; Aquaviva, C; Poirier, K; Moraine, C; Gendrot, C; Verloes, A; Andrès, C; Le Fevre, A C; Souville, I; Steffann, J; des Portes, V; Ropers, H H; Yntema, H G; Fryns, J P; Briault, S; Chelly, J; Cherif, B

2001-04-15

368

Mimicking of Estradiol Binding by Flame Retardants and Their Metabolites: A Crystallographic Analysis  

PubMed Central

Background: Brominated flame retardants (BFRs), used in many types of consumer goods, are being studied because of concerns about possible health effects related to endocrine disruption, immunotoxicity, reproductive toxicity, and neurotoxicity. Tetrabromobisphenol A (TBBPA), the most widely used BFR, and human metabolites of certain congeners of polybrominated diphenyl ether (e.g., 3-OH-BDE-47) have been suggested to inhibit estrogen sulfotransferase, potentially affecting estrogen metabolism. Objectives: Our primary goal was to understand the structural mechanism for inhibition of the hormone-metabolizing enzyme estrogen sulfotransferase by certain BFRs. We also sought to understand various factors that facilitate the binding of flame retardants in the enzyme binding pocket. Methods: We used X-ray crystallography to obtain atomic detail of the binding modes of TBBPA and 3-OH-BDE-47 to estrogen sulfotransferase for comparison with binding of the endogenous substrate estradiol. Results: The crystal structures reveal how BFRs mimic estradiol binding as well as the various interactions between the compounds and protein residues that facilitate its binding. In addition, the structures provide insights into the ability of the sulfotransferase substrate binding pocket to accommodate a range of halogenated compounds that satisfy minimal structural criteria. Conclusions: Our results show how BFRs or their metabolites can bind to and inhibit a key hormone-metabolizing enzyme, potentially causing endocrine disruption. Citation: Gosavi RA, Knudsen GA, Birnbaum LS, Pedersen LC. 2013. Mimicking of estradiol binding by flame retardants and their metabolites: a crystallographic analysis. Environ Health Perspect 121:1194–1199;?http://dx.doi.org/10.1289/ehp.1306902 PMID:23959441

Gosavi, Rajendrakumar A.; Knudsen, Gabriel A.; Birnbaum, Linda S.

2013-01-01

369

Hybrid GPCR\\/Cadherin (Celsr) Proteins in Rat Testis Are Expressed With Cell Type Specificity and Exhibit Differential Sertoli Cell-Germ Cell Adhesion Activity  

Microsoft Academic Search

Spermatogenesis requires Sertoli cell-germ cell ad- hesion for germ cell survival and maturation. Cadherins are a diverse superfamily of adhesion proteins; structurally unique members of this superfamily (celsr cadherins) are hybrid molecules containing extra- cellular cadherin repeats connected to a G protein-coupled receptor transmembrane motif. Here we demonstrate postnatal testicular mRNA expression of the 3 celsr paralogs (celsr1, celsr2, and

STEPHANIE A. BEALL; KIM BOEKELHEIDE; KAMIN J. JOHNSON

2005-01-01

370

Developmental Expression of the Neuron-specific N-Acetylglucosaminyltransferase Vb (GnT-Vb/IX) and Identification of Its in Vivo Glycan Products in Comparison with Those of Its Paralog, GnT-V*  

PubMed Central

The severe phenotypic effects of altered glycosylation in the congenital muscular dystrophies, including Walker-Warburg syndrome, muscle-eye-brain disease, Fukuyama congenital muscular dystrophy, and congenital muscular dystrophy 1D, are caused by mutations resulting in altered glycans linked to proteins through O-linked mannose. A glycosyltransferase that branches O-Man, N-acetylglucosaminyltransferase Vb (GnT-Vb), is highly expressed in neural tissues. To understand the expression and function of GnT-Vb, we studied its expression during neuromorphogenesis and generated GnT-Vb null mice. A paralog of GnT-Vb, N-acetylglucosaminyltransferase (GnT-V), is expressed in many tissues and brain, synthesizing N-linked, ?1,6-branched glycans, but its ability to synthesize O-mannosyl-branched glycans is unknown; conversely, although GnT-Vb can synthesize N-linked glycans in vitro, its contribution to their synthesis in vivo is unknown. Our results showed that deleting both GnT-V and GnT-Vb results in the total loss of both N-linked and O-Man-linked ?1,6-branched glycans. GnT-V null brains lacked N-linked, ?1,6-glycans but had normal levels of O-Man ?1,6-branched structures, showing that GnT-Vb could not compensate for the loss of GnT-V. By contrast, GnT-Vb null brains contained normal levels of N-linked ?1,6-glycans but low levels of some O-Man ?1,6-branched glycans. Therefore, GnT-V could partially compensate for GnT-Vb activity in vivo. We found no apparent change in ?-dystroglycan binding of glycan-specific antibody IIH6C4 or binding to laminin in GnT-Vb null mice. These results demonstrate that GnT-V is involved in synthesizing branched O-mannosyl glycans in brain, but the function of these branched O-mannosyl structures is unresolved using mice that lack these glycosyltransferases. PMID:22715095

Lee, Jin Kyu; Matthews, Russell T.; Lim, Jae-Min; Swanier, Kiara; Wells, Lance; Pierce, J. Michael

2012-01-01

371

Overload retardation effects on stress corrosion behaviour of prestressing steel  

Microsoft Academic Search

This paper analyses overload retardation effects on stress corrosion cracking (scc) of high-strength pearlitic steel for civil engineering use in prestressed concrete. Fatigue pre-cracking load on the samples generates compressive residual stresses in the vicinity of the crack tip which improve the macroscopic scc behaviour, delaying either the metal dissolution or the hydrogen entry, thus increasing the fracture load in

J. Toribio; A. M. Lancha

1996-01-01

372

IQ and the Death Penalty: Verifying Mental Retardation.  

ERIC Educational Resources Information Center

Whether or not subjects can simulate mental retardation, a consideration that has implications in criminal cases, was studied using 21 adult Caucasian males between 20 and 30 years of age, largely comprised of students and staff employees of the University of New Mexico. Subjects were asked to give genuine and simulated responses to two major test…

Keyes, Denis William

373

Home Care and Management of the Mentally Retarded Child.  

ERIC Educational Resources Information Center

The manual details a behavioral and developmental assessment procedure, treatment techniques and method of planning home training programs for mentally retarded children. Focus is on normal preschool development up through 5 years of age. Aims are to help the child function at maximum level by providing practical suggestions to parents for…

Vulpe, Shirley German

374

Clinical Assessment of Sensorimotor Knowledge in Nonverbal, Severely Retarded Clients.  

ERIC Educational Resources Information Center

Reviews history and research of sensorimotor and language development in handicapped children, two research studies on the relationship between sensorimotor development and communication status in nonverbal severely mentally retarded subjects, problems using standardized sensorimotor scales, and an alternative approach involving direct measurement…

Snyder-McLean, Lee; And Others

1988-01-01

375

Mentally Retarded Adolescents: Evaluation of Communication Strategies in Different Settings.  

ERIC Educational Resources Information Center

Verbal interactions of 17 French mentally retarded adolescents in 4 different conversational situations were studied. Results showed that subjects differentiated between interlocutors, exhibited minimal control over conversation with nonhandicapped and unknown people, and more frequently took control of the conversation when talking with a known…

Bolognini, Monique; And Others

1988-01-01

376

Mental Retardation; General References. Exceptional Children Bibliography Series.  

ERIC Educational Resources Information Center

Included are 12 abstracts and descriptive terms designed principally for the general audience dealing with the mentally handicapped. Documents included concern general information on retardation, education, teaching methods, and advice for parents. Also provided are a subject and author index, user information, and ordering procedures for the…

Council for Exceptional Children, Reston, VA. Information Center on Exceptional Children.

377

Reaction Time and Mild Mental Retardation: High Speed Scanning Reexamined.  

ERIC Educational Resources Information Center

Reexamination of three studies was undertaken to investigate factors involved in reaction time of mildly retarded Ss in high speed scanning. It was suggested that specification of processing stages where efficiency varies across populations may not be possible based on results from high speed scanning tasks. (CL)

Silverman, Wayne; Harris, Gilbert

1982-01-01

378

Flame Retardants in Commercial Use or Development for Textiles  

Microsoft Academic Search

Non-durable and semi-durable flame retardants based mostly on phosphate or phosphonate salts continue to be used on infrequently washed or disposable goods, and recent improvements have been made to impart better `hand' or some limited wash resistance. Backcoating with insoluble ammonium polyphosphate, usually with additives and binders to provide intumescence, has been found effective on charrable fabrics. However, the leading

Edward D. Weil; Sergei V. Levchik

2008-01-01

379

Library Services for Persons Who Are Mentally Retarded: Guidelines.  

ERIC Educational Resources Information Center

These guidelines are intended to assist library staff in making provisions for mentally retarded patrons. An initial assessment of the staff attitudes is recommended, followed by disability awareness exercises. Establishing contact with group homes and developmental centers is discussed, including specific steps to follow in making initial contact…

Hodges, Laura J.

380

Saran film is fire-retardant in oxygen atmosphere  

NASA Technical Reports Server (NTRS)

Saran was tested for flammability as a wrapping on TFE-insulated electrical wire bundles in oxygen gas at pressures of 7.5 psia and 14.7 psia. It was found to be fire retardant or self-extinguishing in most instances.

Goodwin, J. T.; Herrera, W. R.

1968-01-01

381

Nonvocal Communication for Norverbal Retarded Children. Final Report.  

ERIC Educational Resources Information Center

Twenty-eight moderately and profoundly retarded children (9 to 17 years old) on one unit of a center for the developmentally disabled were taught a nonvocal symbol system based on that developed by D. Premack. Children varied in speech level from totally nonverbal to some who had simple language skills. The symbol system used a behavioral approach…

Deich, Ruth F.; Hodges, Patricia M.

382

Varieties of Repetitive Behavior in Autism: Comparisons to Mental Retardation  

Microsoft Academic Search

Systematic study of abnormal repetitive behaviors in autism has been lacking despite the diagnostic significance of such behavior. The occurrence of specific topographies of repetitive behaviors as well as their severity was assessed in individuals with mental retardation with and without autism. The occurrence of each behavior category, except dyskinesias, was higher in the autism group and autistic subjects exhibited

James W. Bodfish; Frank J. Symons; Dawn E. Parker; Mark H. Lewis

2000-01-01

383

The Mentally Retarded and the Law Project CAMIO, Volume 3.  

ERIC Educational Resources Information Center

Reviewed are statutory and case laws affecting arrest, prosecution, and treatment of the mentally retarded (MR) offender as part of Project CAMIO, (Correctional Administration and the Mentally Incompetent Offender), a Texas study to determine the incidence of criminal incarceration of the MR and to identify laws, procedures, and practices which…

Haskins, Jimmy R.; Friel, Charles M.

384

Arts and Crafts for Use with Mentally Retarded Students.  

ERIC Educational Resources Information Center

GRADES OR AGES: Mentally retarded children of any age. SUBJECT MATTER: Arts and crafts. ORGANIZATION AND PHYSICAL APPEARANCE: The guide is divided into sections according to the material to be used. Section headings are: Paper, Fabrics, Wood, Metal, Nature, Miscellaneous, and Painting. Each section is laid out in three parallel columns, one each…

Child, Toni, Ed.

385

Predictors of Job Tenure for New Hires with Mental Retardation.  

ERIC Educational Resources Information Center

In South Carolina, 10,169 individuals with mental retardation were served by the state disability agency and 22.7% were employed during 1997-2000, with 68% keeping their job for more than 1 year. Food service, manufacturing, disability services, grocery, and retail companies employed the majority of those who worked at least 3 years. (Contains…

Pierce, Kristen; McDermott, Suzanne; Butkus, Stanley

2003-01-01

386

Observational Studies of Retarded Children with Multiple Stereotyped Movements.  

ERIC Educational Resources Information Center

Three relatively long-term observational studies, involving seven retarded preschool children, each of whom exhibited multiple stereotypes, were conducted to determine the extent to which the type of activity or setting had any effect upon the rates of stereotyped movements. (Author)

Baumeister, Alfred A.; And Others

1980-01-01

387

Mental Retardation Policy and Research: The Unfulfilled Promise.  

ERIC Educational Resources Information Center

The author cites reasons for the negligible impact of research on public policy regarding mental retardation. He suggests that research is secondary to economic, political, and social factors, and that the research enterprise is fragmented and uncoordinated and is not oriented toward the need of policy makers. (Author/CL)

Baumeister, Alfred A.

1981-01-01

388

Detection of THz pulses by phase retardation in lithium tantalate  

Microsoft Academic Search

Freely propagating THz pulses are recorded in a thin lithium tantalate crystal by monitoring the phase retardation of a femtosecond probe pulse. This technique permits the determination of the temporal shape of the THz pulse in the picosecond time domain and offers the exciting prospect of up-converting the spatial THz beam profile into the optical wavelength range in real time,

P. Uhd Jepsen; C. Winnewisser; M. Schall; V. Schyja; S. R. Keiding; H. Helm

1996-01-01

389

Children with mental retardation and epilepsy: demographics and general concerns.  

PubMed

Epilepsy is the most frequent additional handicap in children with mental retardation, with a reported prevalence between 5 and 50 percent. Demographics, issues of control of epilepsy and general attitudes to the care of these youngsters are considered in an effort to increase the availability of needed dental services. PMID:10997243

Waldman, H B; Swerdloff, M; Perlman, S P

2000-01-01

390

Teaching Mild to Moderately Retarded Students with Computers.  

ERIC Educational Resources Information Center

The paper reviews the literature on use of computers with retarded students in three chapters dealing respectively with the historical context, current issues, and future directions. The chapter on the historical context reviews research on the efficacy of teaching machines with this population. Research on the effectiveness of computer-assisted…

Berger, Robert

391

Deinstitutionalization of Persons with Mental Retardation: Behavioral Outcomes.  

ERIC Educational Resources Information Center

The paper reviews experimental/contrast groups and longitudinal studies of changes in adaptive behavior associated with retarded persons moving from state institutions to small community living arrangements.The paper summarizes outcomes in overall behavior, 7 specific behavior domains, and problem behavior. All 18 studies reported at least some…

Larson, Sheryl A.; Lakin, K. Charlie

1989-01-01

392

Aerobic Fitness for the Severely and Profoundly Mentally Retarded.  

ERIC Educational Resources Information Center

The booklet discusses the aerobic fitness capacities of severely/profoundly retarded students and discusses approaches for improving their fitness. An initial section describes a method for determining the student's present fitness level on the basis of computations of height, weight, blood pressure, resting pulse, and Barach Index and Crampton…

Bauer, Dan

1981-01-01

393

Maternal Reaction to Diagnosis of Mental Retardation: A Retrospective Study.  

ERIC Educational Resources Information Center

This study measured current perceptions of stress of mothers (n=35) of children with mental retardation and compared these to their recollections of the initial diagnosis. Analysis revealed that more subjects with low stress scores had their spouse present at the time of diagnosis and recalled positive suggestions offered by the attending…

Wood, Thomas A.; Flynt, Samuel W.

1991-01-01

394

Practitioner Review: Psychopharmacology in Children and Adolescents with Mental Retardation  

ERIC Educational Resources Information Center

Background: The use of psychotropic medication to treat children and adults with mental retardation (MR) has a long and extensive history. There are no identified medications to address specific cognitive deficits among persons with MR. Instead, psychotropic medications are used to treat specific behavioral symptoms and/or psychiatric syndromes.…

Handen, Benjamin L.; Gilchrist, Richard

2006-01-01

395

Proportional retarded control of a second order system  

Microsoft Academic Search

A strategy for the tuning of a second order system in closed loop with a proportional retarded control law, based on the root location analysis of the system, is proposed. It is validated by achieving a significant reduction of the oscillatory behavior of a cart pendulum experimental setup.

R. Villafuerte; S. Mondie; C. Vazquez; J. Collado

2009-01-01

396

Sentencing the Mentally Retarded to Death: An Eighth Amendment Analysis  

Microsoft Academic Search

Today, on death rows across the United States, sit a number of men with the minds of children. These people are mentally retarded. Typical of these individuals is Limmie Arthur, who currently is imprisoned at Central Correctional Institution in Columbia, South Carolina. Although Arthur is twenty-eight years old, all the mental health professionals who have evaluated him, including employees of

John H. Blume; David Bruck

1988-01-01

397

Molecular Genetic Approaches to Human Diseases Involving Mental Retardation.  

ERIC Educational Resources Information Center

Recombinant DNA techniques provide new approaches to the diagnosis and analysis of inherited human diseases associated with mental retardation, such as Lesch-Nyhan syndrome, phenylketonauria, the Fragile X syndrome, Down syndrome, and those associated with deletions or duplications of subchromosomal regions. (Author/CL)

Latt, Samuel A.; And Others

1984-01-01

398

L'Arche: Homes for People Who Are Mentally Retarded.  

ERIC Educational Resources Information Center

Describes L'Arche, an international federation of homes for mentally retarded people, and explores the views of Jean Vanier, the organization's founder, on issues of social justice and world peace. Compares the therapeutic relationships formed in L'Arche communities to healing counselor-client relationships and discusses the role of the counselor…

Harris, George

1987-01-01

399

Phonological Reading Skills Acquisition by Children with Mental Retardation  

ERIC Educational Resources Information Center

Twenty children with mental retardation (MR), age 7-12, completed a phonological reading skills program over approximately 10 weeks. As a result of the instruction, they were better able to sound out learned and transfer words compared to a control group matched on age, IQ, nonword reading, language comprehension, and phonemic awareness. Final…

Conners, Frances A.; Rosenquist, Celia J.; Sligh, Allison C.; Atwell, Julie A.; Kiser, Tanya

2006-01-01

400

Psychopathology in Children and Adolescents with ASD without Mental Retardation  

ERIC Educational Resources Information Center

This study analyzes subclinical psychopathology in children and adolescents with autism spectrum disorders (ASD) without mental retardation with no comorbid disorder, assessed by an extensive general psychopathology interview. The K-SADS-PL was administered to a group of 25 patients with ASD (mean age = 12.80 ± 2.86 years) and 25 healthy controls…

Caamaño, Marta; Boada, Leticia; Merchán-Naranjo, Jessica; Moreno, Carmen; Llorente, Cloe; Moreno, Dolores; Arango, Celso; Parellada, Mara

2013-01-01

401

PHENYLKETONURIA, AN INHERITED METABOLIC DISORDER ASSOCIATED WITH MENTAL RETARDATION.  

ERIC Educational Resources Information Center

ADDRESSED TO PUBLIC HEALTH WORKERS AND PHYSICIANS IN GENERAL PRACTICE, THE PAMPHLET INTRODUCES METHODS OF DETECTING AND MANAGING PHENYLKETONURIA, AN INHERITED METABOLIC DISORDER ASSOCIATED WITH MENTAL RETARDATION. INFORMATION, UPDATED FROM THE 1961 EDITION, IS INCLUDED ON THE INCIDENCE AND GENETICS, BIOCHEMISTRY, AND CLINICAL COURSE OF THE…

CENTERWALL, WILLARD R.; CENTERWALL, SIEGRIED A.

402

Mental Retardation: Determining Eligibility for Social Security Benefits.  

ERIC Educational Resources Information Center

The Social Security Administration (SSA) provides income support and medical benefits for adults with mental retardation unable to perform substantial gainful activity through the Disability Insurance (DI) program and the Supplemental Security Income (SSI) program. SSI benefits are also provided to families of children and adolescents who evidence…

Reschly, Daniel J., Ed.; Myers, Tracy G., Ed.; Hartel, Christine R., Ed.

403

A Hierarchical Analysis of the WAIS Performance of Adolescent Retardates.  

ERIC Educational Resources Information Center

A Wherry-Wherry hierarchical factor solution was obtained on the Wechsler Adult Intelligence Scale (WAIS) subtest performance of 100 adolescent retardates. The hierarchical arrangement of abilities obtained was consistent with Vernon's model of cognitive structure and previous reports. A g-factor and two major group factors were evident.…

Swassing, Ray

1978-01-01

404

WAIS Subtest Score Characteristics of Institutionalized Mentally Retarded Samples.  

ERIC Educational Resources Information Center

Scaled scores on Wechsler Adult Intelligence Scale subtests were compared among five samples of institutionalized mentally retarded (aged 16 - 71 years) from the east coast (509 Ss), west coast (436 Ss), and three from the midwest (113, 51, and 111 Ss). (Author/PHR)

Hill, A. Lewis

1978-01-01

405

Two reciprocal translocations associated with microcephaly and retardation  

Microsoft Academic Search

The first case is reported of a karyotype containing two apparently unrelated reciprocal translocations, involving chromosomes 1, 2, 5, and 7. It is suggested that the patient's psychomotor retardation and microcephaly may be the result of the loss of a small amount of chromosomal material accompanying these translocations.

E F Bell; D Warburton

1977-01-01

406

Microcephaly, mental retardation, cataracts, and hypogonadism in sibs: Martsolf's syndrome  

Microsoft Academic Search

The association of microcephaly, mental retardation, cataracts, and hypogonadism is described in sibs (brother and sister) of consanguineous parents. These features are consistent with a diagnosis of Martsolf's syndrome. In addition, one sib had a cardiomyopathy while the other had cardiac failure.

M G Harbord; M Baraitser; J Wilson

1989-01-01

407

A Physical Education Evaluation for the Mentally Retarded.  

ERIC Educational Resources Information Center

A physical education evaluation was constructed which was flexible enough to measure the varying degrees of retardation. Validity was determined by submitting the test to a jury of experts. Reliability was ascertained by administering the same test to the same students three times with two week intervals between testing. Objectivity was determined…

Rose, Albert

408

A Guide for Teachers of Trainable Mentally Retarded Children.  

ERIC Educational Resources Information Center

The guide for teachers of trainable mentally retarded (TMR) children is thought to be valuable especially to teachers, administrators, and other workers in public schools who are involved in educational programs for the children. Discussion of a general approach to the problem of educating TMR children in the public schools includes the topics of…

Oklahoma State Dept. of Education, Oklahoma City. Div. of Special Education.

409

Arsenic Occurrence, Mobility, and Retardation in Sandstone and  

E-print Network

Arsenic Occurrence, Mobility, and Retardation in Sandstone and Dolomite Formations of the Fox River of groundwater arsenic (100 µg L-1 ) 1.3 � 10-6 M) are found in the Fox River Valley, eastern Wisconsin, shown previously to cause elevated arsenic in groundwater. Detailed mineralogical and chemical analyses

Sahai, Nita

410

Silica Fume as a Radon Retardant from Concrete  

E-print Network

Silica Fume as a Radon Retardant from Concrete K . N . Y U , * , R . V . B A L E N D R A N to be the radon source in concrete. Recently, silica fume is introduced as a partial substitution in Portland exhalation rates from concrete cubes with silica fume were measured using charcoal canisters

Yu, K.N.

411

Role taking and social competence in autism and mental retardation  

Microsoft Academic Search

Recent data suggest that individuals with autism show deficits in social cognitive abilities when compared with nonautistic persons matched for mental age. These deficits have been proposed as a basis for the social interaction difficulties seen in autistic persons. In the present study, autistic youth were compared with a matched group of nonautistic mentally retarded youth on three role-taking tasks

Donald P. Oswald; Thomas H. Ollendick

1989-01-01

412

Everyday Cognition among Mildly Mentally Retarded Adults: An Ethnographic Approach.  

ERIC Educational Resources Information Center

Results of participant-observation techniques used to study the everyday cognition and problem-solving process in marketing tasks defined and organized by mildly mentally retarded adults, revealed five "composites" of strategic behavior. An association between composite and early life experiences was also shown. (Author/CL)

Levine, Harold G.; Langness, L. L.

1985-01-01

413

Environmental release and behavior of brominated flame retardants  

Microsoft Academic Search

Recently, environmental problems relating to brominated flame retardants (BFRs) have become a matter of greater concern than ever before, because of the recent marked increase in levels of polybrominated diphenyl ethers (PBDEs) found in human milk in Sweden and North America. The question that arises is whether environmental levels of PBDEs and other BFRs will continue to increase, causing toxic

Isao Watanabe; Shin-ichi Sakai

2003-01-01

414

An overview of brominated flame retardants in the environment  

Microsoft Academic Search

The presence of brominated flame retardant (BFR) chemicals, and particularly polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD), has become of increasing concern to scientists over the past decade. Environmental studies conducted primarily in Europe, Japan and North America indicate that these chemicals are ubiquitous in sediment and biota. The levels of PBDEs seem to be increasing, and

Cynthia A de Wit

2002-01-01

415

Cursorial spiders retard initial aphid population growth at low densities  

E-print Network

Cursorial spiders retard initial aphid population growth at low densities in winter wheat K Generalist predators contribute to pest suppression in agroecosystems. Spider communities, which form that analyzed the impact, separately and together, of equal densities of these two spider functional groups

Illinois at Chicago, University of

416

Preliminary Study of Imipramine in Profoundly Retarded Residents.  

ERIC Educational Resources Information Center

The effects of imipramine were assessed in 10 profoundly retarded subjects (aged 8-25 years) who exhibited either depressionlike symptoms or acting out behaviors. Results of observation, interval sampling, and the Aberrant Behavior Checklist indicated behavioral deterioration on irritability, lethargy/social withdrawal, and hyperactivity…

Aman, Michael G.; And Others

1986-01-01

417

The Colorado mental retardation and developmental disabilities research center  

Microsoft Academic Search

The Colorado MRRC was one of the original MRRCs funded and has maintained its focus on genetic and nutritional causes of mental retardation and developmental disabilities. Significant discoveries of the center have included a number of metabolic disorders, including glutaric academia types I and II, electron transport flavoprotein (ETF) deficiency, ETF dehydrogenase deficiency, glycerol kinase deficiency, sphingolipidoses, genetic linkages in

Linda S Crnic

2002-01-01

418

Polybrominated diphenyl ether flame retardants in the North American environment  

Microsoft Academic Search

North America consumes over half of the world's production of polybrominated diphenyl ether (PBDE) flame retardants. About 98% of global demand for the Penta-BDE mixture, the constituents of which are the most bioaccumulative and environmentally widespread, resides here. However, research on the environmental distribution of PBDEs in North America has lagged behind that in Northern Europe. Examination of available governmentally

Robert C. Hale; Mehran Alaee; Jon B. Manchester-Neesvig; Heather M. Stapleton; Michael G. Ikonomou

2003-01-01

419

Recreation's Role in the Rehabilitation of the Mentally Retarded.  

ERIC Educational Resources Information Center

The monograph presents the proceedings from a conference sponsored by the Rehabilitation Research and Training Center in Mental Retardation of the University of Oregon (held May 19-21, 1969). Topics concerning recreation's role in the rehabilitation of the mentally handicapped include the following: the role of therapeutic recreation specialists,…

Neal, Larry L., Ed.

420

Environmental Music for the Retarded: A Literature Review.  

ERIC Educational Resources Information Center

Discussed are findings of a review of 21 research reports concerned with the use of environmental music with mentally retarded persons. It is explained that the literature in two data bases was searched and relevant reports examined. The reports are organized into general findings (seven reports), use of music in contingency management (nine…

Wokoun, William

421

Mental Retardation FY 1983. Special Report to Congress.  

ERIC Educational Resources Information Center

The paper reviews mental retardation research activities of the National Institute of Child Health and Human Development (NICHHD) and the National Institute of Neurological and Communicative Disorders and Stroke (NINCDS). Research activities are cited to illustrate the scope of NICHHD's efforts in a variety of biomedial areas. Activities are…

National Inst. of Child Health and Human Development (NIH), Bethesda, MD.

422

A Model for Adult Continuing Education Programs for Retarded Citizens.  

ERIC Educational Resources Information Center

A program of continuing education was developed for institutionalized mentally retarded persons based on the premise that the clients would determine the direction and content of their education. The program involves a curriculum of academic subjects, electives, a student government, and a generic education program. There is a strong emphasis on…

Houchin, John F., Sr.; And Others

423

Standards for Residential Facilities for the Mentally Retarded.  

ERIC Educational Resources Information Center

Presented are standards for residential facilities for the mentally retarded that were developed by the Joint Commission on Accreditation of Hospitals. The accreditation process is said to have two major objects: setting standards for services and determining the degree to which a specific services complies with the designated standards. The…

Joint Commission on Accreditation of Hospitals, Chicago, IL.

424

Psychological Aspects of Sleep Disorders in Children with Mental Retardation.  

ERIC Educational Resources Information Center

This paper reviews literature and clinical experiences on the neurobiological and psychological aspects of sleep in children with mental retardation. The lack of a universal, operational definition of sleep disorders is noted, and a study is cited in which 61% of a group of 20 children (ages 2-13) with developmental disabilities were found to have…

Smith, David T.

425

Assessing the Work Personalities of Mentally Retarded Adults. Final Report.  

ERIC Educational Resources Information Center

A series of studies were conducted to modify the General Aptitude Test Battery (GATB) and the Minnesota Importance Questionnaire (MIQ) for use with mentally retarded individuals. Modification of the GATB consisted of eliminating answer sheets, increasing practice, individual administration, untimed administration, removal of verbally loaded items,…

Lofquist, Lloyd H.; Dawis, Rene V.

426

Helping Adults with Mental Retardation Grieve a Death Loss.  

ERIC Educational Resources Information Center

Adults with mental retardation often grieve the loss of their loved ones. However, many times this grief goes unnoticed and individuals are never given the chance to express their grief and recover from the death of those close to them. This guide is designed for helping professionals, including therapists, clergy, nurses, psychologists, hospice…

Luchterhand, Charlene; Murphy, Nancy

427

Quantitative Assessments of Sensitivity to Reinforcement Contingencies in Mental Retardation.  

ERIC Educational Resources Information Center

Sensitivity to reinforcement contingencies was examined in six individuals with mental retardation using a concurrent operants procedure in the context of a computer game. Results included individual differences in sensitivity and differential sensitivity to rate and magnitude variation. Results suggest that comprehensive assessments of potential…

Dube, William V.; McIlvane, William J.

2002-01-01

428

Relationships between Facial Discrimination and Social Adjustment in Mental Retardation  

ERIC Educational Resources Information Center

Sixty-two adults with mental retardation of heterogeneous etiology performed four facial emotion discrimination tasks and two facial nonemotion tasks. Staff members familiar with the participants completed measures of social adjustment (the Socialization and Communication domains of the Vineland Adaptive Behavior Scales and the Social Performance…

Rojahn, Johannes; Esbensen, Anna J.; Hoch, Theodore A.

2006-01-01

429

Children of Deprivation, Changing the Course of Familial Retardation.  

ERIC Educational Resources Information Center

The growth of preschool familial retarded children was recorded, and attempts were made to alter the course of their development. Of lower socioeconomic class, the 16 subjects aged from 3 to 6, had IQ scores from 50 to 84 and no neurological deficits. One or both of their parents and at least one sibling were mentally subnormal. The subjects and…

Kugel, Robert B.; Parsons, Mabel H.

430

Plasma-enhanced synthesis of green flame retardant cellulosic materials  

Microsoft Academic Search

The natural fiber-containing fabrics and composites are more environmentally friendly, and are used in transportation (automobiles, aerospace), military applications, construction industries (ceiling paneling, partition boards), consumer products, etc. Therefore, the flammability characteristics of the composites based on polymers and natural fibers play an important role. This dissertation presents the development of plasma assisted - green flame retardant coatings for cellulosic

Vladimir Totolin

2010-01-01

431

The Psychopathological Model of Mental Retardation: Theoretical and Therapeutic Considerations.  

ERIC Educational Resources Information Center

Describes a new integrated bio-psycho-social model of etiology for mental retardation. Discusses the problems with current models and the ability of the "universe line" model to integrate data from different research areas, especially cognitive and psychopathologic indicators. Addresses implications of this theoretical approach. (Author/CR)

La Malfa, Giampaolo; Campigli, Marco; Bertelli, Marco; Mangiapane, Antonio; Cabras, Pier Luigi

1997-01-01

432

Measuring Interpersonal Problems in People with Mental Retardation  

ERIC Educational Resources Information Center

Despite interpersonal problems being commonplace in the clinical presentations of people with mental retardation, previous efforts to index interpersonal difficulties have tended to unsatisfactorily rely on external ratings. The Inventory of Interpersonal Problems-32 is a psychometrically robust self-report measure of interpersonal problems in…

Kellett, Stephen; Beail, Nigel; Newman, David W.

2005-01-01

433

Sexual Health and Behavior of Mentally Retarded Pupils in Japan  

ERIC Educational Resources Information Center

Sex education has always been a controversial topic. Although sex education at schools has improved in general, sex education for mentally retarded pupils still encounters prejudice and conservatism as a result of several misconceptions about the subject. This research was performed in the form of a survey of opinions about sex education in…

Tsutsumi, Angela Aparecida

2009-01-01

434

Mental Retardation: Topics of Today--Issues of Tomorrow.  

ERIC Educational Resources Information Center

The monograph examines issues affecting the future of handicapped people generally, and mentally retarded people specifically. E. Meyen introduces the volume and describes how the issues were identified. H. Turnbull and P. Barber, in "Perspectives on Public Policy," discuss such issues as defederalization, redefinition of handicaps, and…

Meyen, Edward L., Ed.

1984-01-01

435

Ventricular ejection force in growth-retarded fetuses.  

PubMed

The objective of this study was to determine whether in growth-retarded fetuses secondary to uteroplacental insufficiency the cardiac ventricles exert a force different from that of appropriately grown fetuses. Doppler echocardiographic studies were performed in 156 appropriately grown fetuses (gestational age 18-38 weeks) and in 72 growth-retarded fetuses (gestational age 24-36 weeks) free from structural and chromosomal abnormalities and characterized by Doppler changes in the umbilical artery and middle cerebral artery suggesting uteroplacental insufficiency as the most likely etiology of the growth defect. Right and left ventricular ejection force values were calculated from velocity waveforms recorded at the level of aortic and pulmonary valves, according to Newton's second law of motion. In appropriately grown fetuses, left and right ventricular ejection force values significantly increased with advancing gestation and the two ventricles exerted similar force. In growth-retarded fetuses, the ventricular ejection force was significantly and symmetrically decreased in both ventricles. Among growth-retarded fetuses, a poorer perinatal outcome was observed in those fetuses in which the ejection force of both ventricles was below the 5th centile of the normal limits for gestation. In 12 growth-retarded fetuses followed longitudinally during the last week preceding intrauterine death or Cesarean section due to antepartum heart-rate late decelerations, a significant decrease of ejection force was found in both ventricles. Finally, a significant relationship was found between the severity of acidosis and right and left ventricular ejection force values in 22 fetuses in which Doppler recordings were performed immediately before cordocentesis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7600206

Rizzo, G; Capponi, A; Rinaldo, D; Arduini, D; Romanini, C

1995-04-01

436

Cadmium-induced fetal growth retardation: protective effect of excess dietary zinc  

SciTech Connect

Reproductive performance and fetal cellular growth and development were investigated in laboratory rats chronically fed low drinking water levels (0, 1.0, 10.0, and 100 ..mu..g/ml) of cadmium (Cd), a known embryotoxic trace element, through gestation. Maternal daily food and water consumption, total weight gain, maternal weight gain, and feed efficiency all decreased with increasing Cd consumption. Term fetal weight was significantly less than that of control subjects only in the group fed 100 ..mu..g Cd/ml drinking water. Total litter weight, however, gradually decreased with increasing Cd concentration due to reduced litter size. Fetal growth retardation was a result of decreased cell division (DNA) and cell growth (protein/DNA ratio). When dams were pair-fed the average daily amount of food consumed by those fed 100 ..mu..g Cd/ml drinking water, maternal weight gain and fetal weight, DNA, and protein/DNA ratio were increased, but not to control levels. Dietary zinc (Zn) supplementation (5.0 ..mu..g/ml drinking water) of Cd-fed dams increased maternal food consumption and fetal weight, DNA, and protein/DNA ratio to control levels. Fetal levels of Cd were extremely low (0.038 to 0.095 ..mu..g/gm fetus) and did not increase with increasing Cd consumption, while placental Cd increased more than 10-fold. Fetal Zn was decreased in Cd-fed dams, and Zn supplementation increased fetal Zn levels, but not to control levels.These results suggest that Cd-induced fetal growth retardation is an indirect rather than a direct effect, resulting from reduced maternal food consumption and metabolism. Since dietary Zn blocks these effects, Cd may be a result of induced Zn deficiency.

Ahokas, R.A.; Dilts, P.V. Jr.; LaHaye, E.B.

1980-01-15

437

Federal Assistance for Mental Retardation and Developmental Disabilities I: A Review through 1961.  

ERIC Educational Resources Information Center

The evolution of federal government mental retardation financial assistance programs from the formation of the U.S. Public Health Service in 1798 through the appointment of the President's Panel on Mental Retardation in 1961 is reviewed. (Author/CL)

Braddock, David

1986-01-01

438

75 FR 28778 - Magma Flood Retarding Structure (FRS) Supplemental Watershed Plan, Pinal County, AZ  

Federal Register 2010, 2011, 2012, 2013

...Natural Resources Conservation Service Magma Flood Retarding Structure (FRS) Supplemental...statement is not being prepared for the Magma Flood Retarding Structure (FRS) Supplemental...The project proposes to rehabilitate the Magma FRS to provide for continued flood...

2010-05-24

439

77 FR 68830 - Certain Projectors With Controlled-Angle Optical Retarders, Components Thereof, and Products...  

Federal Register 2010, 2011, 2012, 2013

...Investigation No. 337-TA-815] Certain Projectors With Controlled-Angle Optical Retarders, Components Thereof, and Products Containing...States after importation of certain projectors with controlled- angle optical retarders, components thereof, and products...

2012-11-16

440

Self-Image in Adolescents with Delayed Puberty and Growth Retardation.  

ERIC Educational Resources Information Center

Adolescents with varying combinations of pubertal delay and growth retardation were given the Offer Self-Image Questionnaire. Delay in sexual maturation by itself had no deleterious effect on self-image but growth retardation did. (Author/GK)

Apter, Alan; And Others

1981-01-01

441

Attentional Habituation and Mental Retardation. A Theoretical Interpretation of MA and IQ Differences in Problem Solving  

ERIC Educational Resources Information Center

A theoretical proposal is offered concerning individual differences in cognitive processes. The focus is on mental retardation and the comparative problem-solving performance of 'normal' and 'retarded' children. (Author/CS)

Furby, Lita

1974-01-01

442

75 FR 52713 - Nationwide Aerial Application of Fire Retardant on National Forest System Lands  

Federal Register 2010, 2011, 2012, 2013

...Service Nationwide Aerial Application of Fire Retardant on National Forest System Lands...continued nationwide aerial application of fire retardant on National Forest System lands...The Forest Service is working to restore fire-adapted ecosystems through...

2010-08-27

443

Molecular characterization of three GnRH receptor paralogs in the European eel, Anguilla anguilla: tissue-distribution and changes in transcript abundance during artificially induced sexual development.  

PubMed

Gonadotropin-releasing hormone receptor (GnRH-R) activation stimulates synthesis and release of gonadotropins in the vertebrate pituitary and also mediates other processes both in the brain and in peripheral tissues. To better understand the differential function of multiple GnRH-R paralogs, three GnRH-R genes (gnrhr1a, 1b, and 2) were isolated and characterized in the European eel. All three gnrhr genes were expressed in the brain and pituitary of pre-pubertal eels, and also in several peripheral tissues, notably gills and kidneys. During hormonally induced sexual maturation, pituitary expression of gnrhr1a (female) and gnrhr2 (male and female) was up-regulated in parallel with gonad development. In the brain, a clear regulation during maturation was seen only for gnrhr2 in the midbrain, with highest levels recorded during early vitellogenesis. These data suggest that GnRH-R2 is the likely hypophysiotropic GnRH-R in male eel, while both GnRH-R1a and GnRH-R2 seems to play this role in female eels. PMID:23416230

Peñaranda, David S; Mazzeo, Ilaria; Hildahl, Jon; Gallego, Victor; Nourizadeh-Lillabadi, Rasoul; Pérez, Luz; Asturiano, Juan F; Weltzien, Finn-Arne

2013-04-30

444

Six opsins from the butterfly Papilio glaucus: molecular phylogenetic evidence for paralogous origins of red-sensitive visual pigments in insects.  

PubMed

It has been hypothesized that the UV-, blue-, and green-sensitive visual pigments of insects were present in the common ancestor of crustaceans and insects, whereas red-sensitive visual pigments evolved later as a result of convergent evolution. This hypothesis is examined with respect to the placement of six opsins from the swallowtail butterfly Papilio glaucus (PglRh1-6) in relationship to 46 other insect, crustacean, and chelicerate opsin sequences. All basal relationships established with maximum parsimony analysis except two are present in the distance and maximum likelihood analyses. In all analyses, the six P. glaucus opsins fall into three well-supported clades, comprised, respectively, of ultraviolet (UV), blue, and long-wavelength (LW) pigments, which appear to predate the radiation of the insects. Lepidopteran green- and red-sensitive visual pigments form a monophyletic clade, which lends support to the hypothesis from comparative physiological studies that red-sensitive visual pigments in insects have paralogous origins. Polymorphic amino acid sites (180, 197, 277, 285, 308), which are essential for generating the spectral diversity among the vertebrate red- and green-sensitive pigments are notably invariant in the Papilio red- and green-sensitive pigments. Other major tuning sites must be sought to explain the spectral diversification among these and other insect visual pigments. PMID:10948267

Briscoe, A D

2000-08-01

445

Population genetics and geographic variation of alcohol dehydrogenase (Adh) paralogs and glucose-6-phosphate dehydrogenase (G6pd) in Drosophila mojavensis.  

PubMed

Populations of Drosophila mojavensis from the deserts of the Baja California peninsula and mainland Mexico utilize different cactus hosts with different alcohol contents. The enzyme alcohol dehydrogenase (ADH) has been proposed to play an important role in the adaptation of Drosophila species to their environment. This study investigates the role of ADH in the adaptation of the cactophilic D. mojavensis to its cactus host. In D. mojavensis and its sibling species, D. arizonae, the Adh gene has duplicated, giving rise to a larval/ovarian form (Adh-1) and an adult form (Adh-2). Studies of sequence variation presented here indicate that the Adh paralogs have followed different evolutionary trajectories. Adh-1 exhibits an excess of fixed amino acid replacements, suggesting adaptive evolution, which could have been a result of several host shifts that occurred during the divergence of D. mojavensis. A 17-bp intron haplotype polymorphism segregates in Adh-2 and has markedly different frequencies in the Baja and mainland populations. The presence of the intron polymorphism suggests possible selection for the maintenance of pre-mRNA structure. Finally, this study supports the proposed Baja California origination of D. mojavensis and subsequent colonization of the mainland accompanied by a host shift. PMID:14660699

Matzkin, Luciano M

2004-02-01

446

Analysis of the Developmental Roles of the Arabidopsis Gibberellin 20-Oxidases Demonstrates That GA20ox1, -2, and -3 Are the Dominant Paralogs[C][W  

PubMed Central

Gibberellin (GA) biosynthesis is necessary for normal plant development, with later GA biosynthetic stages being governed by multigene families. Arabidopsis thaliana contains five GA 20-oxidase (GA20ox) genes, and past work has demonstrated the importance of GA20ox1 and -2 for growth and fertility. Here, we show through systematic mutant analysis that GA20ox1, -2, and -3 are the dominant paralogs; their absence results in severe dwarfism and almost complete loss of fertility. In vitro analysis revealed that GA20ox4 has full GA20ox activity, but GA20ox5 catalyzes only the first two reactions of the sequence by which GA12 is converted to GA9. GA20ox3 functions almost entirely redundantly with GA20ox1 and -2 at most developmental stages, including the floral transition, while GA20ox4 and -5 have very minor roles. These results are supported by analysis of the gene expression patterns in promoter:?-glucuronidase reporter lines. We demonstrate that fertility is highly sensitive to GA concentration, that GA20ox1, -2, and -3 have significant effects on floral organ growth and anther development, and that both GA deficiency and overdose impact on fertility. Loss of GA20ox activity causes anther developmental arrest, with the tapetum failing to degrade. Some phenotypic recovery of late flowers in GA-deficient mutants, including ga1-3, indicated the involvement of non-GA pathways in floral development. PMID:22427334

Powers, Stephen J.; Fernandez-Garcia, Nieves; Urbanova, Terezie; Takebayashi, Yumiko; Seo, Mitsunori; Jikumaru, Yusuke; Benlloch, Reyes; Nilsson, Ove; Ruiz-Rivero, Omar; Phillips, Andrew L.; Wilson, Zoe A.; Thomas, Stephen G.; Hedden, Peter

2012-01-01

447

Analysis of the developmental roles of the Arabidopsis gibberellin 20-oxidases demonstrates that GA20ox1, -2, and -3 are the dominant paralogs.  

PubMed

Gibberellin (GA) biosynthesis is necessary for normal plant development, with later GA biosynthetic stages being governed by multigene families. Arabidopsis thaliana contains five GA 20-oxidase (GA20ox) genes, and past work has demonstrated the importance of GA20ox1 and -2 for growth and fertility. Here, we show through systematic mutant analysis that GA20ox1, -2, and -3 are the dominant paralogs; their absence results in severe dwarfism and almost complete loss of fertility. In vitro analysis revealed that GA20ox4 has full GA20ox activity, but GA20ox5 catalyzes only the first two reactions of the sequence by which GA(12) is converted to GA(9). GA20ox3 functions almost entirely redundantly with GA20ox1 and -2 at most developmental stages, including the floral transition, while GA20ox4 and -5 have very minor roles. These results are supported by analysis of the gene expression patterns in promoter:?-glucuronidase reporter lines. We demonstrate that fertility is highly sensitive to GA concentration, that GA20ox1, -2, and -3 have significant effects on floral organ growth and anther development, and that both GA deficiency and overdose impact on fertility. Loss of GA20ox activity causes anther developmental arrest, with the tapetum failing to degrade. Some phenotypic recovery of late flowers in GA-deficient mutants, including ga1-3, indicated the involvement of non-GA pathways in floral development. PMID:22427334

Plackett, Andrew R G; Powers, Stephen J; Fernandez-Garcia, Nieves; Urbanova, Terezie; Takebayashi, Yumiko; Seo, Mitsunori; Jikumaru, Yusuke; Benlloch, Reyes; Nilsson, Ove; Ruiz-Rivero, Omar; Phillips, Andrew L; Wilson, Zoe A; Thomas, Stephen G; Hedden, Peter

2012-03-01

448

AtGEN1 and AtSEND1, Two Paralogs in Arabidopsis, Possess Holliday Junction Resolvase Activity1[W][OPEN  

PubMed Central

Holliday junctions (HJs) are physical links between homologous DNA molecules that arise as central intermediary structures during homologous recombination and repair in meiotic and somatic cells. It is necessary for these structures to be resolved to ensure correct chromosome segregation and other functions. In eukaryotes, including plants, homologs of a gene called XPG-like endonuclease1 (GEN1) have been identified that process HJs in a manner analogous to the HJ resolvases of phages, archaea, and bacteria. Here, we report that Arabidopsis (Arabidopsis thaliana), a eukaryotic organism, has two functional GEN1 homologs instead of one. Like all known eukaryotic resolvases, AtGEN1 and Arabidopsis single-strand DNA endonuclease1 both belong to class IV of the Rad2/XPG family of nucleases. Their resolvase activity shares the characteristics of the Escherichia coli radiation and UV sensitive C paradigm for resolvases, which involves resolving HJs by symmetrically oriented incisions in two opposing strands. This leads to ligatable products without the need for further processing. The observation that the sequence context influences the cleavage by the enzymes can be interpreted as a hint for the existence of sequence specificity. The two Arabidopsis paralogs differ in their preferred sequences. The precise cleavage positions observed for the resolution of mobile nicked HJs suggest that these cleavage positions are determined by both the substrate structure and the sequence context at the junction point. PMID:25037209

Bauknecht, Markus; Kobbe, Daniela

2014-01-01

449

FLAME RETARDANT TREATMENTS _________________________________________________ All decorations, drapes, signs, banners, sails, acoustical materials, hay, straw, moss, split bamboo, plastic cloth, christms  

E-print Network

, christms trees, and similar decorative materials must be flame retardant to the satisfaction of the Fire Department by either a State Fire Marshall's certification of flame retardant or the ability to pass a field27 FLAME RETARDANT TREATMENTS _________________________________________________ All decorations

Hemmers, Oliver

450

American Association on Mental Retardation 149 VOLUME 108, NUMBER 3: 149160 MAY 2003 AMERICAN JOURNAL ON MENTAL RETARDATION  

E-print Network

JOURNAL ON MENTAL RETARDATION Receptive Language Skills of Adolescents and Young Adults With Down investigated the receptive language of adolescents and young adults with Down syn- drome (n 25) or fragile X report on a study of the receptive language skills of adolescents and young adults with Down syn- drome

Nguyen, Danh

451

American Association on Mental Retardation 181 VOLUME 108, NUMBER 3: 181193 MAY 2003 AMERICAN JOURNAL ON MENTAL RETARDATION  

E-print Network

of the University of Massachusetts Medical School Nancy Dennis Catholic University Raquel Loiselle and Nicholas AAmerican Association on Mental Retardation 181 VOLUME 108, NUMBER 3: 181­193 MAY 2003 AMERICAN. Chechile Shriver Center of the University of Massachusetts Medical School Abstract Abilities of individuals

Dennis, Nancy

452

American Association on Mental Retardation 445 VOLUME 107, NUMBER 6: 445454 NOVEMBER 2002 AMERICAN JOURNAL ON MENTAL RETARDATION  

E-print Network

School Nancy A. Dennis Catholic University Christina P. Strawbridge Shriver Center of the UniversityAmerican Association on Mental Retardation 445 VOLUME 107, NUMBER 6: 445­454 NOVEMBER 2002 AMERICAN of Massachusetts Medical School Abstract Matching-to-sample skills are involved in language acquisition

Dennis, Nancy

453

Specific deficiency of Plzf paralog, Zbtb20, in Sertoli cells does not affect spermatogenesis and fertility in mice  

PubMed Central

Ztbt20 is a POK family transcription factor and primarily functions through its conserved C2H2 Krüppel type zinc finger and BTB/POZ domains. The present study was designed to define the function of the Zbtb20, in vivo, during mouse spermatogenesis. Immunohistochemical studies revealed that ZBTB20 protein was localized specifically in the nuclei of Sertoli cells in seminiferous tubules. To investigate its role during spermatogenesis, we crossed Amh-Cre transgenic mice with Zbtb20 floxp mice to generate conditionally knockout mice (cKO) in which Zbtb20 was specifically deleted in Sertoli cells. The cKO mice were fertile and did not show any detectable abnormalities in spermatogenesis. Taken together, though specific deletion of transcription factor Zbtb20 in Sertoli cells has no apparent influence on spermatogenesis, its specific localization in Sertoli cells makes Zbtb20 a useful marker for the identification of Sertoli cells in seminiferous tubules. PMID:25395169

Jiang, Xiaohua; Zhang, Huan; Yin, Shi; Zhang, Yuanwei; Yang, Weimei; Zheng, Wei; Wang, Liu; Wang, Zheng; Bukhari, Ihtisham; Cooke, Howard J.; Iqbal, Furhan; Shi, Qinghua

2014-01-01

454

Process for spinning flame retardant elastomeric compositions. [fabricating synthetic fibers for high oxygen environments  

NASA Technical Reports Server (NTRS)

Flame retardant elastomeric compositions comprised of either spandex type polyurethane having halogen containing polyols incorporated into the polymer chain, conventional spandex type polyurethanes in physical admixture with flame retardant additives, or fluoroelastomeric resins in physical admixture with flame retardant additives were developed. Methods are described for preparing fibers of the flame retardant elastomeric materials and manufactured articles as well as nonelastic materials such as polybenzimidazoles, fiberglass, and nylons, for high oxygen environments.

Howarth, J. T.; Sheth, S.; Sidman, K. R.; Massucco, A. A. (inventors)

1978-01-01

455

Creating a Technology Toolkit for Students with Mental Retardation: A Systematic Approach  

ERIC Educational Resources Information Center

In 1991, the Association for Retarded Citizens (ARC) of the United States issued a position statement stating that assistive technology (AT) could be a useful tool for individuals with mental retardation. The Division on Mental Retardation and Developmental Disabilities of the Council for Exceptional Children published a position statement…

Parette, Phil; Wojcik, Brian W.

2004-01-01

456

MOTHERS OF RETARDED CHILDREN, HOW THEY FEEL, WHERE THEY FIND HELP.  

ERIC Educational Resources Information Center

THE RESEARCH STUDY INVESTIGATED HOW MOTHERS OF MENTALLY RETARDED CHILDREN PERCEIVED THE RETARDATION, HOW THEY MADE DECISIONS IN SEEKING AND USING HELP, AND HOW THEY REACTED TO AND VALUED SERVICES RENDERED. THE 24 SUBJECTS WERE MOTHERS WHOSE RETARDED CHILDREN WERE CLASSIFIED BRAIN INJURED (INCLUDING MONGOLOID), HAD IQ'S BELOW 54, AND WERE LESS THAN…

EHLERS, WALTER H.

457

A Plea for Consideration of Ecological Validity in the Experimental Psychology of Mental Retardation.  

ERIC Educational Resources Information Center

Problems with experimental research on mental retardation include: (1) difficulties with defining mental retardation; (2) neglect in demonstrating causal relationships; and (3) reliance on methodology not necessarily appropriate for defining the criteria of retardation. The author advocates abandoning definitions based on intelligence tests and…

Brooks, Penelope H.; Baumeister, Alfred A.

1983-01-01

458

Problems of Mentally Retarded Adults: A Study of Rehabilitation Service Consumers and Providers.  

ERIC Educational Resources Information Center

Identified and ranked problems of mentally retarded adults identified by mentally retarded persons and by rehabilitation service providers. Problem areas included employment, community living, and social skills. Approximately one-third of the problems were mutually listed, emphasizing the need for the input of retarded adults themselves. (JAC)

Foss, Gilbert; Bostwick, David

1981-01-01

459

Mental Retardation: Definition, Classification, and Systems of Supports. 10th Edition.  

ERIC Educational Resources Information Center

This manual, the 10th edition of a regularly published definition and classification work on mental retardation, presents five key assumptions upon which the definition of mental retardation is based and a theoretical model of five essential dimensions that explain mental retardation and how to use the companion s