996 resultados para R-MUTANTS


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The present study compared IQs and Verbal-Performance IQ discrepancies estimated from two seven-subtest short forms of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) in a sample of 100 subjects referred for neuropsychological assessment. The short forms of Warrington, James, and Maciejewski (1986) and Ward (1990) yielded similar correlation coefficients and absolute error rates with respect to WAIS-R IQs, although the Warrington short form requires more time to administer and score. Both short forms were able to detect significant Verbal-Performance IQ discrepancies 70% of the time. However, they incorrectly yielded significant discrepancies for approximately 25% of the sample who did not have significant differences on the full WAIS-R. The results do not support reporting and interpreting significant Verbal-Performance IQ discrepancies estimated from these short forms.

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Ectopic calcification (EC), which is the pathological deposition of calcium and phosphate in extra-skeletal tissues, may be associated with hypercalcaemic and hyperphosphataemic disorders, or it may occur in the absence of metabolic abnormalities. In addition, EC may be inherited as part of several monogenic disorders and studies of these have provided valuable insights into the metabolic pathways regulating mineral metabolism. For example, studies of tumoural calcinosis, a disorder characterised by hyperphosphataemia and progressive EC, have revealed mutations of fibroblast growth factor 23 (FGF23), polypeptide N-acetyl galactosaminyltransferase 3 (GALNT3) and klotho (KL), which are all part of a phosphate-regulating pathway. However, such studies in humans are limited by the lack of available large families with EC, and to facilitate such studies we assessed the progeny of mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) for EC. This identified two mutants with autosomal recessive forms of EC, and reduced lifespan, designated Ecalc1 and Ecalc2. Genetic mapping localized the Ecalc1 and Ecalc2 loci to a 11.0 Mb region on chromosome 5 that contained the klotho gene (Kl), and DNA sequence analysis identified nonsense (Gln203Stop) and missense (Ile604Asn) Kl mutations in Ecalc1 and Ecalc2 mice, respectively. The Gln203Stop mutation, located in KL1 domain, was severely hypomorphic and led to a 17-fold reduction of renal Kl expression. The Ile604Asn mutation, located in KL2 domain, was predicted to impair klotho protein stability and in vitro expression studies in COS-7 cells revealed endoplasmic reticulum retention of the Ile604Asn mutant. Further phenotype studies undertaken in Ecalc1 (kl203X/203X) mice demonstrated elevations in plasma concentrations of phosphate, FGF23 and 1,25-dihydroxyvitamin D. Thus, two allelic variants of Kl that develop EC and represent mouse models for tumoural calcinosis have been established. © 2015 Esapa et al.

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Objective Certain mutations in ANKH, which encodes a multiple-pass transmembrane protein that regulates inorganic pyrophosphate (PPi) transport, are linked to autosomal-dominant familial chondrocalcinosis. This study investigated the potential for ANKH sequence variants to promote sporadic chondrocalcinosis. Methods ANKH variants identified by genomic sequencing were screened for association with chondrocalcinosis in 128 patients with severe sporadic chondrocalcinosis or pseudogout and in ethnically matched healthy controls. The effects of specific variants on expression of common markers were evaluated by in vitro transcription/translation. The function of these variants was studied in transfected human immortalized CH-8 articular chondrocytes. Results Sporadic chondrocalcinosis was associated with a G-to-A transition in the ANKH 5′-untranslated region (5′-UTR) at 4 bp upstream of the start codon (in homozygotes of the minor allele, genotype relative risk 6.0, P = 0.0006; overall genotype association P = 0.02). This -4-bp transition, as well as 2 mutations previously linked with familial and sporadic chondrocalcinosis (+14 bp C-to-T and C-terminal GAG deletion, respectively), but not the French familial chondrocalcinosis kindred 143-bp T-to-C mutation, increased reticulocyte ANKH transcription/ANKH translation in vitro. Transfection of complementary DNA for both the wild-type ANKH and the -4-bp ANKH protein variant promoted increased extracellular PPi in CH-8 cells, but unexpectedly, these ANKH mutants had divergent effects on the expression of extracellular PPi and the chondrocyte hypertrophy marker, type X collagen. Conclusion A subset of sporadic chondrocalcinosis appears to be heritable via a -4-bp G-to-A ANKH 5′-UTR transition that up-regulates expression of ANKH and extracellular PPi in chondrocyte cells. Distinct ANKH mutations associated with heritable chondrocalcinosis may promote disease by divergent effects on extracellular PPi and chondrocyte hypertrophy, which is likely to mediate differences in the clinical phenotypes and severity of the disease.

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Progeny of mice treated with the mutagen N-ethyl-N-nitrosourea (ENU) revealed a mouse, designated Longpockets (Lpk), with short humeri, abnormal vertebrae, and disorganized growth plates, features consistent with spondyloepiphyseal dysplasia congenita (SEDC). The Lpk phenotype was inherited as an autosomal dominant trait. Lpk/+ mice were viable and fertile and Lpk/Lpk mice died perinatally. Lpk was mapped to chromosome 15 and mutational analysis of likely candidates from the interval revealed a Col2a1 missense Ser1386Pro mutation. Transient transfection of wild-type and Ser1386Pro mutant Col2a1 c-Myc constructs in COS-7 cells and CH8 chondrocytes demonstrated abnormal processing and endoplasmic reticulum retention of the mutant protein. Histology revealed growth plate disorganization in 14-day-old Lpk/+ mice and embryonic cartilage from Lpk/+ and Lpk/Lpk mice had reduced safranin-O and type-II collagen staining in the extracellular matrix. The wild-type and Lpk/+ embryos had vertical columns of proliferating chondrocytes, whereas those in Lpk/Lpk mice were perpendicular to the direction of bone growth. Electron microscopy of cartilage from 18.5 dpc wild-type, Lpk/+, and Lpk/Lpk embryos revealed fewer and less elaborate collagen fibrils in the mutants, with enlarged vacuoles in the endoplasmic reticulum that contained amorphous inclusions. Micro-computed tomography (CT) scans of 12-week-old Lpk/+ mice revealed them to have decreased bone mineral density, and total bone volume, with erosions and osteophytes at the joints. Thus, an ENU mouse model with a Ser1386Pro mutation of the Col2a1 C-propeptide domain that results in abnormal collagen processing and phenotypic features consistent with SEDC and secondary osteoarthritis has been established.

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We have examined the magnetotransport properties and the structure, by Rietveld refinement of powder X-ray data, of the phases RE(1.2)Sr(1.8)Mn(2)O(7) (RE = La, Pr, Nd). We find that on cooling, La1.2Sr1.8Mn2O7 undergoes a transition to a nearly perfect ferromagnet with 90% magnetization at 1.45 T, as reported by earlier workers, but the Pr and Nd phases show only a small magnetization that grows gradually as the temperature is decreased. There seems to be significant correlation between electrical transport and the Jahn-Teller elongation of the apical Mn-O bonds in these systems. The elongation of the apical Mn-O bonds forces the nine-coordinate rock-salt site to be occupied preferentially by the smaller rare-earth-metal cations. This preferential occupation is reliably obtained from the X-ray refinement. All three title phases show a magnetoresistance ratio of about 4(corresponding to a magnetoresistance, [R(0)-R(H)]/R(0), of about 75%) at a field of 7 T and temperatures around 100 K.

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SHMT (serine hydoxymethyltransferase), a type I pyridoxal 5'-phosphate-dependent enzyme, catalyses the conversion of L-serine and THF (tetrahydrofolate) into glycine and 5,10-methylene THE SHMT also catalyses several THF-independent side reactions such as cleavage of P-hydroxy amino acids, trans-amination, racemization and decarboxylation. In the present study, the residues Asn(341), Tyr(60) and Phe(351), which are likely to influence THF binding, were mutated to alanine, alanine and glycine respectively, to elucidate the role of these residues in THF-dependent and -independent reactions catalysed by SHMT. The N341A and Y60A bsSHMT (Bacillus stearothermophilus SHMT) mutants were inactive for the THF-dependent activity, while the mutations had no effect on THF-independent activity. However, mutation of Phe(351) to glycine did not have any effect oil either of the activities. The crystal structures of the glycine binary complexes of the mutants showed that N341A bsSHMT forms an external aldimine as in bsSHMT, whereas Y60A and F351G bsSHMTs exist as a Mixture of internal/external aldimine and gem-diamine forms. Crystal structures of all of the three Mutants obtained in the presence of L-allo-threonine were similar to the respective glycine binary complexes. The structure of the ternary complex of F351G bsSHMT with glycine and FTHF (5-formyl THF) showed that the monoglutamate side chain of FTHF is ordered in both the subunits of the asymmetric unit, unlike in the wild-type bsSHMT. The present studies demonstrate that the residues Asn(341) and Tyr(60) are pivotal for the binding of THF/FTHF, whereas Phe(351) is responsible for the asymmetric binding of FTHF in the two subunits of the dimer.

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Petrifilm(R) (6410) was used directly on lamb carcasses to enumerate coliforms. 10 sites on 30 carcasses were sampled at each of 4 separate meat processing establishments (works). Coliform counts obtained by this technique were statistically analysed using analysis of variance (ANOVA) to select the optimum sampling sites on the carcass and to assess contamination of the carcass by gut flora at a particular establishment. There was a large variation between sites and between works. In general, works 3 and 4 produced cleaner carcasses than works 2, which in turn was cleaner than works 1. Works 1, 2 and 4 used conventional dressing techniques and works 3 used the inverted dressing method, therefore, the coliform counts found at works 3 and 4 are achievable regardless of dressing technique. Coliform bacteria were most concentrated around the posterior pelvic rim and less prevalent at the carcass extremities. The posterior pelvic rim (sites 3 and 4) had higher (P < 0.05) coliform counts than the exterior ventral flank area (sites 5, 6, 7 and 8), which in turn had higher (P < 0.05) counts than the proximal hind and proximal fore limbs (sites 1, 2, 9 and 10) across all works. With in-line routine testing it is recommended that the majority of carcasses sampled should give coliform counts of <50 cfu/20 cm2 for sites 4 and 8. Reprinted with permission from Journal of Food Protection. Copyright held by the International Association of Food Protection, Des Moines, Iowa, USA. Authors affifiation. J.A.Guthrie & K.J.Dunlop International Food Institute of Queensland, Department of Primary Industries, Rockhampton and G.A.Saunders Veterinary Public Health Division, Livestock and Meat Authority of Queensland, Emerald.

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E.S.R. investigations of γ-irradiated ferroelectric Sodium ammonium selenate, NaNH4SeO4•2H2O and its deuteriated analogue in powder and single crystal forms have led to a deeper understanding of the nature of the ferroelectric transition of 180 K. A number of paramagnetic species formed due to γ-irradiation have been identified on the basis of their g-factors and hyperfine features from 77Se. The radical SeO4 has been used as a microprobe in studying the phase transition.

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A trial was undertaken to evaluate the effect of microwaves on seed mortality of three weed species. Seeds of rubber vine (Cryptostegia grandiflora R.Br.), parthenium (Parthenium hysterophorous L.) and bellyache bush (Jatropha gossypiifolia L.) were buried at six depths (0, 2.5, 5, 10, 20 and 40 cm) in coarse sand maintained at one of two moisture levels, oven dry or wet (field capacity), and then subjected to one of five microwave radiation durations of (0, 2, 4, 8 and 16 min). Significant interactions between soil moisture level, microwave radiation duration, seed burial depth and species were detected for mortality of seeds of all three species. Maximum seed mortality of rubber vine (88%), parthenium (67%) and bellyache bush (94%) occurred in wet soil irradiated for 16 min. Maximum seed mortality of rubber vine and bellyache bush seeds occurred in seeds buried at 2.5 cm depth whereas that of parthenium occurred in seeds buried at 10 cm depth. Maximum soil temperatures of 114.1 and 87.5°C in dry and wet soil respectively occurred at 2.5 cm depth following 16 min irradiation. Irrespective of the greater soil temperatures recorded in dry soil, irradiating seeds in wet soil generally increased seed mortality 2.9-fold compared with dry soil. Moisture content of wet soil averaged 5.7% compared with 0.1% for dry soil. Results suggest that microwave radiation has the potential to kill seeds located in the soil seed bank. However, many factors, including weed species susceptibility, determine the effectiveness of microwave radiation on buried seeds. Microwave radiation may be an alternative to conventional methods at rapidly depleting soil seed banks in the field, particularly in relatively wet soils that contain long lived weed seeds.

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The objective of my dissertation Pull (or Draught, or Moves) at the Parnassus , is to provide a deeper understanding of Nordic Middle Class radicalism of the 1960 s as featured in Finland-Swedish literature. My approach is cultural materialist in a broad sense; social class is regarded a crucial aspect of the contents and contexts of the novels and literary discussions explored. In the first volume, Middle Class With A Human Face , novels by Christer Kihlman, Jarl Sjöblom, Marianne Alopaeus, and Ulla-Lena Lundberg, respectively, are read from the points of view of place, emotion, and power. The term "cryptotope" is used to designate the hidden places found to play an important role in all of these four narratives. Also, the "chronotope of the provincial small town", described by Mikhail Bakhtin in 1938, is exemplified in Kihlman s satirical novel, as is the chronotope of of war (Algeria, Vietnam) in those of Alopaeus and Lundberg s. All the four novels signal changes in the way general "scripts of emotions", e.g. jealousy, are handled and described. The power relations in the novels are also read, with reference to Michel Foucault. As the protagonists in two of them work as journalists, a critical discussion about media and Bourgeois hegemony is found; the term "repressive legitimation" is created to grasp these patterns of manipulation. The Modernist Debate , part II of the study, concerns a literary discussion between mainly Finland-Swedish authors and critics. Essayist Johannes Salminen (40) provided much of the fuel for the debate in 1963, questioning the relevance to contemporary life of the Finland-Swedish modernist tradition of the 1910 s and 1920 s. In 1965, a group of younger authors and critics, including poet Claes Andersson (28), followed up this critique in a debate taking place mainly in the newspaper Vasabladet. Poets Rabbe Enckell (62), Bo Carpelan (39) and others defended a timeless poetry. This debate is contextualized and the changing literary field is analyzed using concepts provided by sociologist Pierre Bourdieu. In the thesis, the historical moment of Middle Class radicalism with a human face is regarded a temporary luxury that new social groups could afford themselves, as long as they were knocking over the statues and symbols of the Old Bourgeoisie. This is not to say that all components of the Sixties strategy have lost their power. Some of them have survived and even grown, others remain latent in the gene bank of utopias, waiting for new moments of change.

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We have investigated the structure, magnetic and dielectric properties of the double perovskite oxides, R2NiMnO6 (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho and Y). We could refine powder X-ray diffraction patterns of all the phases on the basis of monoclinic (P2(1)/n) double perovskite structure where Ni and Mn atoms are ordered at 2c and 2d sites, respectively. All the phases are ferromagnetic insulators exhibiting relatively low dielectric loss and dielectric constants in the range 15-25. The ferromagnetic ordering temperature of the R2NiMnO6 series seems to correlate better with the radius of R3+ atoms than with the average Ni-O-Mn angle (phi) in the double perovskite structure. These results are consistent with all samples having Mn4+ and Ni2+ With minimal antisite disorder.

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Tämä pro gradu -tutkielma on tehty osana Svenska i toppen -projektia, joka alkoi syksyllä 2008 Pohjoismaisten kielten ja pohjoismaisen kirjallisuuden laitoksella. Tutkimuksen tavoitteena on selvittää, mitkä tekijät vaikuttavat lukiolaisten näkökulmasta hyvien tulosten saavuttamiseen ruotsin ylioppilaskirjoituksissa kolmessa suomenkielisessä lukiossa, jotka sijaitsevat Turun, Tampereen ja Joensuun seuduilla. Lisäksi tavoitteena on selvittää, miten maantieteelliset tekijät vaikuttavat opiskelijoiden ruotsin kielen osaamiseen sekä mitä eroja on keskipitkän ja pitkän ruotsin oppimäärän opiskelijoiden asenteissa kieltä kohtaan. Tutkielman aineistona on kolme ryhmähaastattelua, joihin on osallistunut 14 lukiolaista, 11 tyttöä ja 3 poikaa. Haastattelut on tehty joulukuussa 2008 sekä tammi- ja maaliskuussa 2009. Haastatteluissa on käytetty strukturoitua kyselylomaketta, jossa kysytään opiskelijoiden näkemyksiä ruotsin opiskelusta. Tutkimusmenetelmänä on kvalitatiivinen tutkimusote, jossa on piirteitä kolmesta eri menetelmästä: tapaustutkimuksesta, etnografisesta tutkimuksesta sekä temaattisesta analyysistä. Tärkeimpänä teoriataustana on ruotsi toisena kielenä -tutkimus, oppiminen sosiokonstruktivistisena ilmiönä sekä motivaatiotutkimus. Tarkastelen kielenoppijaa luokkahuoneessa sosiaalisena osallistujana omassa oppimisprosessissaan. Oppiminen nähdään kokonaisuutena, johon kuuluu eri osa-alueita, esimerkiksi koulujen käytännöt, yhteisön vaikutus oppimiseen sekä opiskelijan identiteetin muokkautuminen kouluyhteisössä. Motivaatiota tarkastelen kielenoppimisen näkökulmasta, ja se koostuu erilaisista dynaamisista vaiheista, esimerkiksi tavoitteiden asettamisesta oppimisprosessin alussa, valintojen tekemisestä sekä motivaation ylläpitämisestä oppimisprosessin kuluessa. Tutkimuksen tulokset osoittavat, että suurin yksittäinen syy menestykseen opiskelijoiden näkökulmasta on opettaja, joka omalla toiminnallaan voi merkittävästi parantaa opiskelijoiden oppimisedellytyksiä. Työhön panostaminen, opiskelijoiden yksilöllinen kohtaaminen myös luokkahuoneen ulkopuolella ja esimerkiksi omien oppimateriaalien valmistaminen ovat opettajaan liittyviä tekijöitä, jotka voivat nostaa opiskelijoiden motivaatiota huomattavasti. Myös lukion maantieteellisellä sijainnilla on vaikutusta. Paikkakunnilla, joilla ruotsin kieltä käytetään vähän, korostuu opettajan rooli kielellisen oppimisympäristön luomisessa. Keskipitkän ja pitkän ruotsin opiskelijoiden välillä ei tutkimuksessa ilmene eroja asenteissa kieltä kohtaan.