582 resultados para VanSledright, Bruce A
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The kinetoplast genetic code deviates from the universal code in that 90% of mitochondrial tryptophans are specified by UGA instead of UGG codons. A single nucleus-encoded tRNA Trp(CCA) is used by both nuclear and mitochondria genes, since all kinetoplast tRNAs are imported into the mitochondria from the cytoplasm. To allow decoding of the mitochondrial UGA codons as tryptophan, the tRNA Trp(CCA) anticodon is changed to UCA by an editing event. Two tryptophanyl tRNA synthetases (TrpRSs) have been identified in Trypanosoma brucei: TbTrpRS1 and TbTrpRS2 which localize to the cytoplasm and mitochondria respectively. We used inducible RNA interference (RNAi) to assess the role of TbTrpRSs. Our data validates previous observations of TrpRS as potential drug design targets and investigates the RNAi effect on the mitochondria of the parasite.
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Hearing loss in Meniere's disease (MD) is associated with loss of spiral ganglion neurons and hair cells. In a guinea pig model of endolymphatic hydrops, nitric oxide synthases (NOS) and oxidative stress mediate loss of spiral ganglion neurons. To test the hypothesis that functional variants of NOS1 and NOS2A are associated with MD, wed genotyped three functional variants of NOS1 (rs41279104,rs2682826, and a cytosine-adenosine microsatellite repeat in exon 1f) and the CCTTT repeat in the promoter of NOS2A gene (rs3833912) in two independent MD sets(273 patients in total) and 550 controls. A third cohort of American patients was genotyped as replication cohort for the CCTTT repeat. Neither allele nor genotype frequencies of rs41279104 and rs2682826 were associated with MD, although longer alleles of the cytosine-adenosine microsatellite repeat were marginally significant (corrected p = 0.05) in the Mediterranean cohort but not in a second Galicia cohort. Shorter numbers of the CCTTT repeat in NOS2A were significantly more frequent in Galicia controls (OR = 0.37 [CI, 0.18-0.76], corrected p =0.04), but this finding could not be replicated in Mediterranean or American case-control populations. Meta-analysis did not support an association between CCTTT repeats and risk for MD. Severe hearing loss (>75 dB) was also not associated with any functional variants studied. Functional variants of NOS1 and and NOS2A do not confer susceptibility for MD.
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Background: Inflammation is associated with heart failure (HF) risk factors and also directly affects myocardial function. However, the association between inflammation and HF risk in older adults has not been adequately evaluated. Methods: The association of baseline serum concentrations of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF- ), and C-reactive protein (CRP) with incident HF was assessed with Cox proportional hazards models among 2610 older persons without prevalent HF enrolled in the Health, Aging, and Body Composition (Health ABC) Study (age, 73.6±2.9 years; 48.3% men; 59.6% white). Results: Median (interquartile range) baseline concentrations of IL-6, TNF- , and CRP were 1.80 (1.23, 2.76) pg/mL, 3.14 (2.41, 4.06) pg/mL, and 1.64 (0.99, 3.04) µg/mL, respectively. On follow-up (median, 9.4 years), 311 participants (11.9%) developed HF. In models controlling for clinical predictors of HF and incident coronary heart disease, doubling of IL-6, TNF- , and CRP concentrations was associated with 34% (95% CI, 18 -52%; P<.001), 33% (95% CI, 9 - 63%; P=.006), and 13% (95% CI, 3-24%; P=.01) increase in HF risk, respectively. In models including all 3 markers, IL-6 and TNF- , but not CRP, remained significant. Findings were similar across sex and race. Post-HF ejection fraction (EF) was available in 239 (76.8%) cases. When only cases with preserved EF were considered (n=105), IL-6 (HR per doubling, 1.57; 95% CI, 1.28 -1.94; P<.001), TNF- (HR per doubling, 1.59; 95% CI, 1.12-2.26; P=.01), and CRP (HR per doubling, 1.23; 95% CI, 1.05-1.44; P=.01) were all associated with HF risk in adjusted models. In contrast, when only cases with reduced EF (n=134) were considered, only IL-6 attained marginal significance in adjusted models (HR per doubling, 1.20; 95% CI, 0.99 -1.46; P=.06). Participants with 2 or 3 markers above median had pronounced HF risk in adjusted models (HR, 1.66; 95% CI, 1.12-2.46; P=.01; and HR, 1.76; 95% CI, 1.16 -2.65; P=.007, respectively). Addition of IL-6 to the clinical Health ABC HF model improved discrimination (C index from 0.717 to 0.734; P=.001) and fit (decreased Bayes information criterion by 17.8; P<.001). Conclusions: Inflammatory markers are associated with HF risk among older adults and may improve HF risk stratification.
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Since 1984, Anopheles (Kerteszia) lepidotus has been considered a mosquito species that is involved in the transmission of malaria in Colombia, after having been incriminated as such with epidemiological evidence from a malaria outbreak in Cunday-Villarrica, Tolima. Subsequent morphological analyses of females captured in the same place and at the time of the outbreak showed that the species responsible for the transmission was not An. lepidotus, but rather Anopheles pholidotus. However, the associated morphological stages and DNA sequences of An. pholidotus from the foci of Cunday-Villarrica had not been analysed. Using samples that were caught recently from the outbreak region, the purpose of this study was to provide updated and additional information by analysing the morphology of female mosquitoes, the genitalia of male mosquitoes and fourth instar larvae of An. pholidotus, which was confirmed with DNA sequences of cytochrome oxidase I and rDNA internal transcribed spacer. A total of 1,596 adult females were collected in addition to 37 larval collections in bromeliads. Furthermore, 141 adult females, which were captured from the same area in the years 1981-1982, were analysed morphologically. Ninety-five DNA sequences were analysed for this study. Morphological and molecular analyses showed that the species present in this region corresponds to An. pholidotus. Given the absence of An. lepidotus, even in recent years, we consider that the species of mosquitoes that was previously incriminated as the malaria vector during the outbreak was indeed An. pholidotus, thus ending the controversy.
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This dissertation involves a close reading of Springsteen’s lyrics in relation to the thematic concerns of the Tom Joad album. Enquiring into the sometimes multiple levels of significance that these lyrics can be seen to express, in order to show the manner in which Springsteen mirrors the broader thematic concerns of Steinbeck’s The Grapes of Wrath’ s novel but also adapts and reinterprets these themes for his own time. In this sense, I will try to underline the ways in which, for Springsteen’s vision of his country in the 1990’s, the presence of troublesome issues from decades before is one that can, in certain ways, still be seen, felt and experienced. It is in this manner that the ghost of Tom Joad is summoned
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RATIONALE: The aim of the work was to develop and validate a method for the quantification of vitamin D metabolites in serum using ultra-high-pressure liquid chromatography coupled to mass spectrometry (LC/MS), and to validate a high-resolution mass spectrometry (LC/HRMS) approach against a tandem mass spectrometry (LC/MS/MS) approach using a large clinical sample set. METHODS: A fast, accurate and reliable method for the quantification of the vitamin D metabolites, 25-hydroxyvitamin D2 (25OH-D2) and 25-hydroxyvitamin D3 (25OH-D3), in human serum was developed and validated. The C3 epimer of 25OH-D3 (3-epi-25OH-D3) was also separated from 25OH-D3. The samples were rapidly prepared via a protein precipitation step followed by solid-phase extraction (SPE) using an HLB μelution plate. Quantification was performed using both LC/MS/MS and LC/HRMS systems. RESULTS: Recovery, matrix effect, inter- and intra-day reproducibility were assessed. Lower limits of quantification (LLOQs) were determined for both 25OH-D2 and 25OH-D3 for the LC/MS/MS approach (6.2 and 3.4 µg/L, respectively) and the LC/HRMS approach (2.1 and 1.7 µg/L, respectively). A Passing & Bablok fit was determined between both approaches for 25OH-D3 on 662 clinical samples (1.11 + 1.06x). It was also shown that results can be affected by the inclusion of the isomer 3-epi-25OH-D3. CONCLUSIONS: Quantification of the relevant vitamin D metabolites was successfully developed and validated here. It was shown that LC/HRMS is an accurate, powerful and easy to use approach for quantification within clinical laboratories. Finally, the results here suggest that it is important to separate 3-epi-25OH-D3 from 25OH-D3. Copyright © 2012 John Wiley & Sons, Ltd.
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Geochemical data that is derived from the whole or partial analysis of various geologic materialsrepresent a composition of mineralogies or solute species. Minerals are composed of structuredrelationships between cations and anions which, through atomic and molecular forces, keep the elementsbound in specific configurations. The chemical compositions of minerals have specific relationships thatare governed by these molecular controls. In the case of olivine, there is a well-defined relationshipbetween Mn-Fe-Mg with Si. Balances between the principal elements defining olivine composition andother significant constituents in the composition (Al, Ti) have been defined, resulting in a near-linearrelationship between the logarithmic relative proportion of Si versus (MgMnFe) and Mg versus (MnFe),which is typically described but poorly illustrated in the simplex.The present contribution corresponds to ongoing research, which attempts to relate stoichiometry andgeochemical data using compositional geometry. We describe here the approach by which stoichiometricrelationships based on mineralogical constraints can be accounted for in the space of simplicialcoordinates using olivines as an example. Further examples for other mineral types (plagioclases andmore complex minerals such as clays) are needed. Issues that remain to be dealt with include thereduction of a bulk chemical composition of a rock comprised of several minerals from which appropriatebalances can be used to describe the composition in a realistic mineralogical framework. The overallobjective of our research is to answer the question: In the cases where the mineralogy is unknown, arethere suitable proxies that can be substituted?Kew words: Aitchison geometry, balances, mineral composition, oxides
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INTRODUCTION: In recent decades the treatment of non-specific low back pain has turned to active modalities, some of which were based on cognitive-behavioural principles. Non-randomised studies clearly favour functional multidisciplinary rehabilitation over outpatient physiotherapy. However, systematic reviews and meta-analysis provide contradictory evidence regarding the effects on return to work and functional status. The aim of the present randomised study was to compare long-term functional and work status after 3-week functional multidisciplinary rehabilitation or 18 supervised outpatient physiotherapy sessions. METHODS: 109 patients with non-specific low back pain were randomised to either a 3-week functional multidisciplinary rehabilitation programme, including physical and ergonomic training, psychological pain management, back school and information, or 18 sessions of active outpatient physiotherapy over 9 weeks. Primary outcomes were functional disability (Oswestry) and work status. Secondary outcomes were lifting capacity (Spinal Function Sort and PILE test), lumbar range-of-motion (modified-modified Schöber and fingertip-to-floor tests), trunk muscle endurance (Shirado and Biering-Sörensen tests) and aerobic capacity (modified Bruce test). RESULTS: Oswestry disability index was improved to a significantly greater extent after functional multidisciplinary rehabilitation compared to outpatient physiotherapy at follow-up of 9 weeks (P = 0.012), 9 months (P = 0.023) and 12 months (P = 0.011). Work status was significantly improved after functional multidisciplinary rehabilitation only (P = 0.012), resulting in a significant difference compared to outpatient physiotherapy at 12 months' follow-up (P = 0.012). Secondary outcome results were more contrasted. CONCLUSIONS: Functional multidisciplinary rehabilitation was better than outpatient physiotherapy in improving functional and work status. From an economic point of view, these results should be backed up by a cost-effectiveness study.
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The Editorial presents the focus, scope, policies, and the inaugural issue of NeoBiota, a new open access peer-reviewed journal of biological invasions. The new journal NeoBiota is a continuation of the former NEOBIOTA publication series. The journal will deal with all aspects of invasion biology and impose no restrictions on manuscript size neither on use of color. NeoBiota implies an XML-based editorial workflow and several cutting-edge innovations in publishing and dissemination, such as semantic markup of and enhancements to published texts, data publication, and extensive cross-linking within the journal and to external sources
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En los últimos años ha tenido lugar un debate teórico de gran interés sobre la naturaleza organizacional del terrorismo yihadista y su evolución a lo largo de la última década. El centro de dicha discusión ha sido ocupado por dos profesores estadounidenses: Marc Sageman (2004; 2008) y Bruce Hoffman (2008). Mientras que el primero argumenta que la respuesta contraterrorista posterior al 11 de septiembre de 2001 ha originado que el control efectivo de las acciones terroristas se haya desplazado a un nivel de base, dando lugar a una yihad sin líderes donde los grupos terroristas juegan un papel secundario, el segundo sostiene que las organizaciones formales, y mas concretamente Al Qaeda Central, continua ejerciendo un grado sustancial de control estratégico y operativo. Los partidarios de una y otra visión han analizado los complots terroristas ejecutad os o desarticulados en los últimos tiempos, llegando a conclusiones diferentes sobre la naturaleza de los procesos de formación de las células terroristas, su vinculación con organizaciones, y cual es el principal perfil de la amenaza terrorista en Occidente: si el proveniente de células independientes y terroristas por imitación (bunchof guysy wannabessegún la terminología usada por Sageman), o el procedente de la acción de organizaciones formales de alcance global. El propósito de este trabajo es realizar una contribución a este debate académico aportando información procedente del ámbito de las actividades terroristas en Internet. Estos datos aportan nuevos elementos de análisis para el debate sobre la naturaleza organizacional de la amenaza yihadista.
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Confronting a recently mated female with a strange male can induce a pregnancy block ('Bruce effect'). The physiology of this effect is well studied, but its functional significance is still not fully understood. The 'anticipated infanticide hypothesis' suggests that the pregnancy block serves to avoid the cost of embryogenesis and giving birth to offspring that are likely to be killed by a new territory holder. Some 'compatible-genes sexual selection hypotheses' suggest that the likelihood of a pregnancy block is also dependent on the female's perception of the stud's and the stimulus male's genetic quality. We used two inbred strains of mice (C57BL/6 and BALB/c) to test all possible combinations of female strain, stud strain, and stimulus strain under experimental conditions (N(total) = 241 mated females). As predicted from previous studies, we found increased rates of pregnancy blocks if stud and stimulus strains differed, and we found evidence for hybrid vigour in offspring of between-strain mating. Despite the observed heterosis, pregnancies of within-strain matings were not more likely to be blocked than pregnancies of between-strain matings. A power analysis revealed that if we missed an existing effect (type-II error), the effect must be very small. If a female gave birth, the number and weight of newborns were not significantly influenced by the stimulus males. In conclusion, we found no support for the 'compatible-genes sexual selection hypotheses'.
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Revision of the Leucosphyrus Group of Anopheles (Cellia) (Diptera, Culicidae). This is a comprehensive revision of 20 species of the Leucosphyrus Group of the Neomyzomyia Series of Anopheles (Cellia). Morphological description of the adults, male and female, male genitalia, pupa and fourth-instar larva are provided for each taxon in addition to bionomics, distribution data and systematic discussion for each species, including diagnostic characters. Identification keys for females and fourth-instar larvae are provided. When possible medical importance of each species is included. Illustrations of of the adults, fourth-instar larvae and pupae are provided. Distribution maps for each species are mainly based on the material examined; however, when possible published data were also used. Tables on adult character variations, fourth-instar larval and pupal setal branching are included as appendices. A neotype for An. takasagoensis Morishita and An. sulawesi Koesoemawinangoen, and a lectotype for An. balabacensis Baisas, are designated. The authorship of An. sulawesi previously cited as Waktoedi is corrected to Koesoemawinangoen.