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Find video protocols related to scientific articles indexed in Pubmed.
Chiral recognition with a benzofuran receptor that mimics an oxyanion hole.
Org. Biomol. Chem.
PUBLISHED: 11-07-2014
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A new chiral benzofuran receptor has been synthesized and its properties in the association of amino acid derivatives have been studied. X-ray structures were obtained and these corroborate the presence of an oxyanion-hole motif in these structures.
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Imaging the stereodynamics of methyl iodide photodissociation in the second absorption band: fragment polarization and the interplay between direct and predissociation.
Phys Chem Chem Phys
PUBLISHED: 11-04-2014
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The stereochemistry of methyl iodide photodissociation in the onset of the second absorption B-band has been studied using slice imaging of the CH3(? = 0) and I*((2)P1/2) photoproducts. The stereodynamical data have been crucial to disentangle the photochemistry of methyl iodide in terms of the competition between direct dissociation and electronic predissociation. The origin of the B-band has been established with high accuracy at 201.11 ± 0.12 nm and a depolarization factor due to parent molecule rotation during predissociation has been found to be 0.29 ± 0.06. Analysis of the semiclassical Dixon's bipolar moments extracted from the CH3(? = 0) sliced images indicates that direct excitation to the A-band (3)A1 repulsive state in the vicinity of the origin of the B-band is remarkably enhanced by vibrational coupling between the electronic states involved at the conical intersection through in-plane vibrational motion of the molecule.
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Experimental virus evolution reveals a role of plant microtubule dynamics and TORTIFOLIA1/SPIRAL2 in RNA trafficking.
PLoS ONE
PUBLISHED: 08-18-2014
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The cytoskeleton is a dynamic network composed of filamentous polymers and regulatory proteins that provide a flexible structural scaffold to the cell and plays a fundamental role in developmental processes. Mutations that alter the spatial orientation of the cortical microtubule (MT) array of plants are known to cause important changes in the pattern of cell wall synthesis and developmental phenotypes; however, the consequences of such alterations on other MT-network-associated functions in the cytoplasm are not known. In vivo observations suggested a role of cortical MTs in the formation and movement of Tobacco mosaic virus (TMV) RNA complexes along the endoplasmic reticulum (ER). Thus, to probe the significance of dynamic MT behavior in the coordination of MT-network-associated functions related to TMV infection and, thus, in the formation and transport of RNA complexes in the cytoplasm, we performed an evolution experiment with TMV in Arabidopsis thaliana tor1/spr2 and tor2 mutants with specific defects in MT dynamics and asked whether TMV is sensitive to these changes. We show that the altered cytoskeleton induced genetic changes in TMV that were correlated with efficient spread of infection in the mutant hosts. These observations demonstrate a role of dynamic MT rearrangements and of the MT-associated protein TORTIFOLIA1/SPIRAL2 in cellular functions related to virus spread and indicate that MT dynamics and MT-associated proteins represent constraints for virus evolution and adaptation. The results highlight the importance of the dynamic plasticity of the MT network in directing cytoplasmic functions in macromolecular assembly and trafficking and illustrate the value of experimental virus evolution for addressing the cellular functions of dynamic, long-range order systems in multicellular organisms.
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[New biomarkers to optimize the selection and follow up of patients with prostate cancer on active surveillance].
Arch. Esp. Urol.
PUBLISHED: 06-11-2014
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Identification of biomarkers that, at the time of diagnosis of prostate cancer (PCa), are associated with presence of disease or a more aggressive behavior will transform the clinical management of this disease. If both patients and clinicians would have reproducible and valid tools to estimate the specific risk of morbidity associated with PCa, then many patients would opt to and join active surveillance (AS) protocols, and consequently costs and comorbidities associated with the current overtreatment of prostate cancer would be reduced. Thus, a biomarker, or a panel of biomarkers, with high specificity to identify patients at risk for progression in AS protocols, would identify those men who could benefit from less intensive AS protocols with less repeated biopsies, so reducing the risk and cost of these invasive procedures. In this review we try to offer an overview of the new markers identified by genomic techniques and to discuss their potential role in an AS context. Moreover, the AS protocol offers an adequate setting for validation of biomarkers associated to disease progression.
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The movement protein (NSm) of Tomato spotted wilt virus is the avirulence determinant in the tomato Sw-5 gene-based resistance.
Mol. Plant Pathol.
PUBLISHED: 05-26-2014
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The avirulence determinant triggering the resistance conferred by the tomato gene Sw-5 against Tomato spotted wilt virus (TSWV) is still unresolved. Sequence comparison showed two substitutions (C118Y and T120N) in the movement protein NSm present only in TSWV resistance-breaking (RB) isolates. In this work, transient expression of NSm of three TSWV isolates [RB1 (T120N), RB2 (C118Y) and non-resistance-breaking (NRB)] in Nicotiana benthamiana expressing Sw-5 showed a hypersensitive response (HR) only with NRB. Exchange of the movement protein of Alfalfa mosaic virus (AMV) with NSm supported cell-to-cell and systemic transport of the chimeric AMV RNAs into N.?tabacum with or without Sw-5, except for the constructs with NBR when Sw-5 was expressed, although RB2 showed reduced cell-to-cell transport. Mutational analysis revealed that N120 was sufficient to avoid the HR, but the substitution V130I was required for systemic transport. Finally, co-inoculation of RB and NRB AMV chimeric constructs showed different prevalence of RB or NBR depending on the presence or absence of Sw-5. These results indicate that NSm is the avirulence determinant for Sw-5 resistance, and mutations C118Y and T120N are responsible for resistance breakdown and have a fitness penalty in the context of the heterologous AMV system.
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Challenges to develop nitrogen-fixing cereals by direct nif-gene transfer.
Plant Sci.
PUBLISHED: 03-25-2014
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Some regions of the developing world suffer low cereal production yields due to low fertilizer inputs, among other factors. Biological N2 fixation, catalyzed by the prokaryotic enzyme nitrogenase, is an alternative to the use of synthetic N fertilizers. The molybdenum nitrogenase is an O2-labile metalloenzyme composed of the NifDK and NifH proteins, which biosyntheses require a number of nif gene products. A challenging strategy to increase cereal crop productivity in a scenario of low N fertilization is the direct transfer of nif genes into cereals. The sensitivity of nitrogenase to O2 and the apparent complexity of nitrogenase biosynthesis are the main barriers identified so far. Expression of active NifH requires the products of nifM, nifH, and possibly nifU and nifS, whereas active NifDK requires the products of nifH, nifD, nifK, nifB, nifE, nifN, and possibly nifU, nifS, nifQ, nifV, nafY, nifW and nifZ. Plastids and mitochondria are potential subcellular locations for nitrogenase. Both could provide the ATP and electrons required for nitrogenase to function but they differ in their internal O2 levels and their ability to incorporate ammonium into amino acids.
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Maillard reaction products modulate gut microbiota composition in adolescents.
Mol Nutr Food Res
PUBLISHED: 03-24-2014
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Scarce data are available concerning effects of certain bioactive substances such as Maillard reaction products (MRP) on the gut microbiota composition, and the question of how a diet rich in MRP affects gut microbiota in humans is still open.
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Expression and purification of NifB proteins from aerobic and anaerobic sources.
Methods Mol. Biol.
PUBLISHED: 03-19-2014
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NifB is the key protein in the biosynthesis of nitrogenase iron-molybdenum cofactor. Due to its extreme sensitivity to O2 and inherent protein instability, NifB proteins must be purified under strict anaerobic conditions by using affinity chromatography methods. We describe here the methods for NifB purification from cells of the strict aerobic nitrogen-fixing bacterium Azotobacter vinelandii, the facultative anaerobic nitrogen-fixing bacterium Klebsiella pneumoniae, and the facultative anaerobic non-nitrogen fixing bacterium Escherichia coli recombinantly expressing a nifB gene of thermophilic origin.
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Purification of O2-sensitive metalloproteins.
Methods Mol. Biol.
PUBLISHED: 03-19-2014
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The most dependable factor to perform successful biochemical experiments in an O2-free environment is the experience required to set up an efficient laboratory, to properly manipulate samples, to anticipate potential O2-related problems, and to maintain the complex laboratory setup operative. There is a long list of O2-related issues that may ruin your experiments. We provide here a guide to minimize these risks.
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Laparoscopic vasectomy in African elephants (Loxodonta africana).
Vet Surg
PUBLISHED: 03-11-2014
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To describe a surgical technique for, and outcome after, laparoscopic vasectomy of free-ranging elephants.
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Clinico-pathological significance of the molecular alterations of the SPOP gene in prostate cancer.
Eur. J. Cancer
PUBLISHED: 03-07-2014
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Speckle-type POZ protein (SPOP) is an E3 ubiquitin ligase adaptor recently described to be mutated in prostate cancer (PCa). Hence, studying the gene expression profile and the presence of SPOP mutations in PCa and understanding its clinico-pathological significance as prognostic and therapeutic biomarker are important to further understand its role in PCa development.
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Genetic variation and possible mechanisms driving the evolution of worldwide fig mosaic virus isolates.
Phytopathology
PUBLISHED: 02-28-2014
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Fig mosaic virus (FMV) is a multipartite negative-sense RNA virus infecting fig trees worldwide. FMV is transmitted by vegetative propagation and grafting of plant materials, and by the eriophyid mite Aceria ficus. In this work, the genetic variation and evolutionary mechanisms shaping FMV populations were characterized. Nucleotide sequences from four genomic regions (each within the genomic RNAs 1, 2, 3, and 4) from FMV isolates from different countries were determined and analyzed. FMV genetic variation was low, as is seen for many other plant viruses. Phylogenetic analysis showed some geographically distant FMV isolates which clustered together, suggesting long-distance migration. The extent of migration was limited, although varied, between countries, such that FMV populations of different countries were genetically differentiated. Analysis using several recombination algorithms suggests that genomes of some FMV isolates originated by reassortment of genomic RNAs from different genetically similar isolates. Comparison between nonsynonymous and synonymous substitutions showed selection acting on some amino acids; however, most evolved neutrally. This and neutrality tests together with the limited gene flow suggest that genetic drift plays an important role in shaping FMV populations.
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[Risk prevention evaluation in the incorporation of new drugs for healthcare practices: a methodological proposal].
Farm Hosp
PUBLISHED: 02-04-2014
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Submit a preventive assessment methodology for the risk of medication errors when incorporating new drugs in clinical practice as well as a description of the types of actions arising from such action.
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Identification of miR-187 and miR-182 as Biomarkers of Early Diagnosis and Prognosis in Patients with Prostate Cancer Treated with Radical Prostatectomy.
J. Urol.
PUBLISHED: 01-29-2014
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miRNAs are noncoding RNAs that negatively regulate target mRNA gene expression. Aberrant miRNA expression is associated with prostate cancer pathogenesis. We identified miRNAs as potential biomarkers for prostate cancer diagnosis and prognosis.
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Somatic NLRP3 mosaicism in Muckle-Wells syndrome. A genetic mechanism shared by different phenotypes of cryopyrin-associated periodic syndromes.
Ann. Rheum. Dis.
PUBLISHED: 12-12-2013
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Familial cold autoinflammatory syndrome, Muckle-Wells syndrome (MWS), and chronic, infantile, neurological, cutaneous and articular (CINCA) syndrome are dominantly inherited autoinflammatory diseases associated to gain-of-function NLRP3 mutations and included in the cryopyrin-associated periodic syndromes (CAPS). A variable degree of somatic NLRP3 mosaicism has been detected in ?35% of patients with CINCA. However, no data are currently available regarding the relevance of this mechanism in other CAPS phenotypes.
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Kinetics of nif gene expression in a nitrogen fixing bacterium.
J. Bacteriol.
PUBLISHED: 11-15-2013
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Nitrogen fixation is a tightly regulated trait. Switching from N2-fixation repressing conditions to the N2-fixing state is carefully controlled in diazotrophic bacteria mainly because of the high-energy demand it imposes. By using quantitative real time PCR and quantitative immunoblotting, we show here how nitrogen fixation (nif) gene expression develops in Azotobacter vinelandii upon derepression. Transient expression of the transcriptional activator-encoding gene, nifA, was followed by subsequent, longer duration waves of expression of the nitrogenase biosynthetic and structural genes. Importantly, expression timing, levels, and NifA-dependence greatly varied among the nif operons. Moreover, the exact concentrations of Nif proteins, and their changes over time, were determined for the first time. Nif protein concentrations were exquisitely balanced; with FeMo-cofactor biosynthetic proteins accumulating at levels 50-100 fold lower than structural proteins. Mutants lacking nitrogenase structural genes, or impaired in FeMo-cofactor biosynthesis, showed over enhanced responses to derepression proportionally to the degree of nitrogenase activity impairment that were consistent with the existence of at least two negative feedback regulatory mechanisms. The first of such mechanisms would respond to the levels of fixed nitrogen whereas the second mechanism appears to respond to the levels of matured NifDK component. Altogether, these findings provide a framework to engineer N2 fixation in non-diazotrophs.
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Role of Azotobacter vinelandii FdxN in FeMo-co biosynthesis.
FEBS Lett.
PUBLISHED: 11-14-2013
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Biosynthesis of metal clusters for the nitrogenase component proteins NifH and NifDK involves electron donation events. Yet, electron donors specific to the biosynthetic pathways of the [4Fe-4S] cluster of NifH, or the P-cluster and the FeMo-co of NifDK, have not been identified. Here we show that an Azotobacter vinelandii mutant lacking fdxN was specifically impaired in FeMo-co biosynthesis. The ?fdxN mutant produced 5-fold less NifB-co, an early FeMo-co biosynthetic intermediate, than wild type. As a consequence, it accumulated FeMo-co-deficient apo-NifDK and was impaired in NifDK activity. We conclude that FdxN plays a role in FeMo-co biosynthesis, presumably by donating electrons to support NifB-co synthesis by NifB. This is the first role in nitrogenase biosynthesis unequivocally assigned to any A. vinelandii ferredoxin.
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Analgesic and motor effects of a high-volume intercoccygeal epidural injection of 0.125% or 0.0625% bupivacaine in adult cows.
Can. J. Vet. Res.
PUBLISHED: 10-15-2013
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The objectives of this study were to determine the analgesic and motor effects of a high-volume intercoccygeal epidural injection of bupivacaine at 2 concentrations in cows. A prospective, randomized, blinded, crossover trial was conducted on 6 adult cows. An indwelling epidural catheter was placed in the first intercoccygeal space and advanced 10 cm cranially. All the cows received 3 treatments with a washout period of 48 h: saline (control), 0.125% bupivacaine (high dose), or 0.0625% bupivacaine (low dose), at a final volume of 0.15 mL per kilogram of body weight, infused manually into the epidural space over a period of 15 min. The anal and tail tone and motor deficits of the pelvic limbs were evaluated in 5 of the cows with use of a numerical rating scale and a visual analogue scale (VAS). Sensory block was assessed in 4 of the cows by the response to needle pricks in different regions with the use of a VAS. Measurements were obtained before and at different time points after injection, up to 360 min. Analysis of variance for repeated measures and post-hoc Tukeys and Dunnetts tests were used. Differences were considered significant when the P-value was ? 0.05. One cow became recumbent 6 h after injection. Anal and tail tones were significantly decreased and motor deficits of the pelvic limbs were significantly increased after bupivacaine treatment compared with control treatment. The overall mean VASpain scores ± standard deviation were 66 ± 8 after control treatment, 52 ± 5 after low-dose bupivacaine treatment, and 43 ± 5 after high-dose bupivacaine treatment. The pain scores were significantly lower in caudal regions up to the saphenous nerve after high-dose bupivacaine treatment compared with control treatment and significantly lower in the anus, vulva, and tail after low-dose bupivacaine treatment compared with control treatment. Thus, analgesia with moderate motor deficits of the pelvic limbs may be obtained with 0.125% bupivacaine administered epidurally.
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Nanoscale resolution for fluorescence microscopy via adiabatic passage.
Opt Express
PUBLISHED: 10-10-2013
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We propose the use of the subwavelength localization via adiabatic passage technique for fluorescence microscopy with nanoscale resolution in the far field. This technique uses a ?-type medium coherently coupled to two laser pulses: the pump, with a node in its spatial profile, and the Stokes. The population of the ? system is adiabatically transferred from one ground state to the other except at the node position, yielding a narrow population peak. This coherent localization allows fluorescence imaging with nanometer lateral resolution. We derive an analytical expression to asses the resolution and perform a comparison with the coherent population trapping and the stimulated-emission-depletion techniques.
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Health-related Internet use by lupus patients in southern Spain.
Clin. Rheumatol.
PUBLISHED: 09-16-2013
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Internet has become a widely used tool by patients seeking information on different diseases. The information regarding lupus patients Internet use is scarce. This study aims to explore the attitudes and practices of lupus patients in southern Spain, regarding Internet use to find health-related information. A survey was carried out including 150 patients from six Andalusian Hospitals. To search for information, 67.3 % of the patients used Internet. The proportion of female Internet users was higher (69.3 vs 46.2 %), particularly those belonging to a patients association (81.8 vs 32.7 %), and are regular users of Internet (80.2 vs 44.4 %); 37.5 % thought the information found in the Internet was of little use or not useful at all, and 58 % of the respondents stated that the information found caused them concern while for 27 %, it was a relief. Most patients preferred the information given by their physicians (63.6 %); 33.9 % considered that the information from both sources was complementary, and 2.5 % preferred the information obtained from the Internet. A percentage of 85.3 of the patients would like their physicians to provide them with information on high-quality sites regarding their illness. Lupus patients make frequent use of the Internet to look for information on their disease. Considering this, and because better-informed patients follow more precisely the indications given by the physician, medical staff should collaborate in the development of high-quality sites for the patient to have additional sources of information.
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Superficial EWSR1-negative undifferentiated small round cell sarcoma with CIC/DUX4 gene fusion: a new variant of Ewing-like tumors with locoregional lymph node metastasis.
Virchows Arch.
PUBLISHED: 08-30-2013
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The present study describes a new case of EWSR1-negative undifferentiated sarcoma with CIC/DUX4 gene fusion. This case is similar to tumors described as primitive undifferentiated round cell sarcomas that occur mainly in the trunk and display an aggressive behavior. To our knowledge, this is the first report of such a tumor presenting locoregional lymph node metastasis. In view of previous studies that prove the existence of a particular variant of undifferentiated sarcoma with Ewing-like morphology and CIC/DUX-4 gene fusion, a search for this gene fusion in all undifferentiated round cell sarcomas should be considered if a conclusive diagnosis cannot be reached following other conventional studies. Although additional cases with more extensive follow-up studies are needed, we believe that EWSR1-negative undifferentiated small round cell sarcoma with CIC/DUX4 gene fusion should be added to the list of new sarcoma variants with the possibility of lymph node metastasis.
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Spectrophotometric detection of susceptibility to anti-malarial drugs.
Malar. J.
PUBLISHED: 08-02-2013
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With malaria drug resistance increasing in prevalence and severity, new technologies are needed to aid and improve the accuracy and clinical relevance of laboratory or field testing for malaria drug resistance. This study presents a method based on simple and reagentless spectroscopic measurements coupled with comprehensive spectral interpretation analysis that provides valuable quantitative information on the morphological and compositional responses of Plasmodium falciparum and infected red blood cells (IRBCs) to anti-malarial treatment.
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Galacto-oligosaccharides derived from lactulose exert a selective stimulation on the growth of Bifidobacterium animalis in the large intestine of growing rats.
J. Agric. Food Chem.
PUBLISHED: 07-25-2013
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There is increasing interest in identifying novel dietary nondigestible carbohydrates capable of modulating the composition and/or metabolic activities of the gut microbiota. This work assessed the differential modulatory influence of novel galacto-oligosaccharides derived from lactulose (GOS-Lu) in comparison with commercial galacto-oligosaccharides derived from lactose (GOS-La) in gut microbiota of growing rats (5 weeks old). Rats were fed either a control diet or diets containing 1% (w/w) of GOS-Lu or GOS-La, and cecal and colonic contents were collected after 14 days of treatment. Compared to controls, GOS-Lu had significantly more bifidobacteria within the large intestine, showing a significant and selective increase of Bifidobacterium animalis in the cecum and colon; however, no significant differences in the number of bifidobacteria among GOS-Lu and GOS-La groups were observed. Both types of GOS significantly increased the number of the Eubacterium rectale / Clostridium coccoides group. These findings support a prebiotic role of galactosyl-fructoses in functional foods.
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Detection and identification of Fabavirus species by one-step RT-PCR and multiplex RT-PCR.
J. Virol. Methods
PUBLISHED: 07-11-2013
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The genus Fabavirus of the family Secoviridae comprises a group of poorly characterized viruses. To date, only five species have been described: Broad bean wilt virus 1 (BBWV-1), Broad bean wilt virus 2 (BBWV-2), Lamium mild mosaic virus (LMMV), Gentian mosaic virus (GeMV) and Cucurbit mild mosaic virus (CuMMV). The development is described of two RT-PCR procedures for the detection and identification of Fabavirus species: a one-step RT-PCR using a single pair of conserved primers for the detection of all fabaviruses, and a one-step multiplex RT-PCR using species-specific primers for the simultaneous detection and identification of the above-mentioned species of the genus Fabavirus. These methods were applied successfully to field samples and the results were compared with those obtained by molecular hybridization and ELISA. The combination of the two techniques enables rapid, sensitive and reliable identification of the five known fabavirus species, as well as the possibility of discovering new species of this genus.
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Roles of four conserved basic amino acids in a ferredoxin-dependent cyanobacterial nitrate reductase.
Biochemistry
PUBLISHED: 06-13-2013
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The roles of four conserved basic amino acids in the reaction catalyzed by the ferredoxin-dependent nitrate reductase from the cyanobacterium Synechococcus sp. PCC 7942 have been investigated using site-directed mutagenesis in combination with measurements of steady-state kinetics, substrate-binding affinities, and spectroscopic properties of the enzymes two prosthetic groups. Replacement of either Lys58 or Arg70 by glutamine leads to a complete loss of activity, both with the physiological electron donor, reduced ferredoxin, and with a nonphysiological electron donor, reduced methyl viologen. More conservative, charge-maintaining K58R and R70K variants were also completely inactive. Replacement of Lys130 by glutamine produced a variant that retained 26% of the wild-type activity with methyl viologen as the electron donor and 22% of the wild-type activity with ferredoxin as the electron donor, while replacement by arginine produces a variant that retains a significantly higher percentage of the wild-type activity with both electron donors. In contrast, replacement of Arg146 by glutamine had minimal effect on the activity of the enzyme. These results, along with substrate-binding and spectroscopic measurements, are discussed in terms of an in silico structural model for the enzyme.
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Off-label uses of anti-TNF therapy in three frequent disorders: Behçets disease, sarcoidosis, and noninfectious uveitis.
Mediators Inflamm.
PUBLISHED: 05-23-2013
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Tumoral necrosis factor ? plays a central role in both the inflammatory response and that of the immune system. Thus, its blockade with the so-called anti-TNF agents (infliximab, etanercept, adalimumab, certolizumab pegol, and golimumab) has turned into the most important tool in the management of a variety of disorders, such as rheumatoid arthritis, spondyloarthropatties, inflammatory bowel disease, and psoriasis. Nonetheless, theoretically, some other autoimmune disorders may benefit from these agents. Our aim is to review these off-label uses of anti-TNF blockers in three common conditions: Behçets disease, sarcoidosis, and noninfectious uveitis. Due to the insufficient number of adequate clinical trials and consequently to their lower prevalence compared to other immune disorders, this review is mainly based on case reports and case series.
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Multiwavelength transmission spectroscopy revisited for the characterization of the protein and polystyrene nanoparticle mixtures.
Appl Spectrosc
PUBLISHED: 04-30-2013
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Multiwavelength Transmission (MWT) UV-Vis-NIR spectroscopy, an effective technique often underutilized for the characterization of processes involving particulates, such as protein aggregation, is systematically explored using bovine serum albumin and a set of NIST-traceable particle size (PS) standards having certified particle diameters over the nominal size range of 30 to 100 nm. The PS standards are used as surrogates for protein aggregates and other contaminants such as oils and microbubbles. Therefore, the standards can be used to quantitatively modify the optical properties of protein solutions and thus observe the effect of the presence of aggregates and other particulates on their wavelength-dependent transmission spectra. The experimental results demonstrate that the changes induced in the optical density spectra of proteins due to the presence of PS particles are detectable and consistent with the expectations set by light scattering theory. It is demonstrated that the size and relative concentrations of the particle populations present in the protein samples can be quantified. Because of the considerable dynamic range of MWT UV-Vis-NIR spectroscopy for particle analysis and its real-time measurement capabilities, this type of spectroscopy can be effectively used for the characterization of protein aggregates and for the continuous real-time monitoring of aggregation processes and for the identification and quantification of contaminants in protein-based products.
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IL2/IL21 region polymorphism influences response to rituximab in systemic lupus erythematosus patients.
Mol. Biol. Rep.
PUBLISHED: 04-29-2013
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To determine whether the IL2/IL21 region, a general autoimmunity locus, contributes to the observed variation in response to rituximab in patients with systemic lupus erythematosus as well as to analyze its influence in a cohort including other autoimmune diseases. rs6822844 G/T polymorphism at the IL2-IL21 region was analyzed by TaqMan assay in 84 systemic lupus erythematosus (SLE) and 60 different systemic autoimmune diseases Spanish patients receiving rituximab. Six months after the first infusion patients were classified, according to the EULAR criteria, as good responders, partial responders and non-responders. A statistically significant difference was observed in GG genotype frequency between responder (total and partial response) (83.56%) and non-responder (45.45%) SLE patients (p=0.010, odds ratio (OR)=6.10 [1.28-29.06]). No association with the response was evident in the group of patients with autoimmune diseases other than lupus. Furthermore, when both groups of patients were pooled in a meta-analysis, a reduced statistical significance of the association was observed (p=0.024, OR=3.53 [1.06-11.64]). Our results show for a first time that IL2-IL21 region seems to play a role in the response to rituximab in SLE patients but not in other autoimmune diseases.
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The complete genome sequence of Lamium mild mosaic virus, a member of the genus Fabavirus.
Arch. Virol.
PUBLISHED: 03-13-2013
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Lamium mild mosaic virus (LMMV) is the only one of the five members of the genus Fabavirus for which there are no nucleotide sequence data. In this study, the complete genome sequence of LMMV was determined and compared with the available complete genome sequences of other members of the genus Fabavirus. The genome was the largest of the genus but maintained the typical organization, with RNA 1 of 6080 nucleotides (nt), RNA 2 of 4065 nt, and an unusually long 3 untranslated region in RNA 2 of 603 nt. Phylogenetic analysis of the amino acid sequences of the protease-polymerase (Pro-Pol) region and the two coat proteins confirmed that LMMV belongs to a distinct species within the genus Fabavirus.
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Characterization of pea (Pisum sativum) seed protein fractions.
J. Sci. Food Agric.
PUBLISHED: 03-08-2013
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Legume seed proteins have to be chemically characterized in order to properly link their nutritional effects with their chemical structure.
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Dose-response effect between cannabis use and psychosis liability in a non-clinical population: evidence from a snowball sample.
J Psychiatr Res
PUBLISHED: 03-02-2013
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This study aimed to explore the associations between daily cannabis use and the specific profiles of subclinical symptoms in a non-clinical population obtained through snowball sampling, taking into account alcohol use, other drug use, social exclusion and age at onset of cannabis use. We included 85 daily cannabis users and 100 non-daily cannabis users. Both the case and the control populations were identified by snowball sampling. Daily cannabis use was associated with more alcohol intake and other drug use, as well as with early onset in the use of cannabis. Daily cannabis use appeared to exert a dose-response effect on first-rank symptoms, mania symptoms and auditory hallucinations, even after adjusting for sex, age, other drug use, social exclusion and age at onset of cannabis use. The paranoid dimension was only associated with the heaviest consumption of cannabis. Initial age of cannabis use modified the effects of daily cannabis use on the first-rank and voices experiences. Daily cannabis use was associated with significantly more first-rank and voices experiences among those subjects who started to use cannabis before 17 years of age. Our study supports the association of psychotic experiences with cannabis use even among non-psychotic subjects.
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Surgical stabilization of shoulder luxation in a pot-bellied pig.
J. Am. Vet. Med. Assoc.
PUBLISHED: 03-01-2013
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Case Description-A 4.6-month-old pot-bellied pig was evaluated because of non-weight-bearing lameness (grade 5/5) in the right forelimb of 4 days duration. Clinical Findings-Clinical and radiographic examination revealed a closed, lateral luxation of the right shoulder joint. Treatment and Outcome-Initial attempts at closed reduction failed to provide adequate stability of the shoulder joint. Open reduction and internal fixation by placement of 2 lateral tension sutures with a system designed for canine cranial cruciate ligament repair provided adequate joint stability and a successful outcome. Conclusions and Clinical Relevance-Stabilization of the shoulder joint with lateral tension sutures after open reduction should be considered for management of lateral shoulder luxation in pot-bellied pigs.
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New insight on the Xq28 association with systemic sclerosis.
Ann. Rheum. Dis.
PUBLISHED: 02-26-2013
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To evaluate whether the systemic sclerosis (SSc)-associated IRAK1 non-synonymous single-nucleotide polymorphism rs1059702 is responsible for the Xq28 association with SSc or whether there are other independent signals in the nearby methyl-CpG-binding protein 2 gene (MECP2).
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Increased CD38 expression in T cells and circulating anti-CD38 IgG autoantibodies differentially correlate with distinct cytokine profiles and disease activity in systemic lupus erythematosus patients.
Cytokine
PUBLISHED: 02-14-2013
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CD38 is a multifunctional protein possessing ADP-ribosyl cyclase activity responsible for both the synthesis and the degradation of several Ca(2+)-mobilizing second messengers. In mammals, CD38 also functions as a receptor. In this study CD38 expression in CD4(+), CD8(+), or CD25(+) T cells was significantly higher in systemic lupus erythematosus (SLE) patients than in Normal controls. Increased CD38 expression in SLE T cells correlated with plasma levels of Th2 (IL-4, IL-10, IL-13) and Th1 (IL-1?, IL-12, IFN-?, TNF-?) cytokines, and was more prevalent in clinically active SLE patients than in Normal controls. In contrast, elevated anti-CD38 IgG autoantibodies were more frequent in clinically quiescent SLE patients (SLEDAI=0) than in Normal controls, and correlated with moderate increased plasma levels of IL-10 and IFN-?. However, clinically active SLE patients were mainly discriminated from quiescent SLE patients by increased levels of IL-10 and anti-dsDNA antibodies, with odds ratios (ORs) of 3.7 and 4.8, respectively. Increased frequency of anti-CD38 autoantibodies showed an inverse relationship with clinical activity (OR=0.43), and in particular with the frequency of anti-dsDNA autoantibodies (OR=0.21). Increased cell death occurred in CD38(+) Jurkat T cells treated with anti-CD38(+) SLE plasmas, and not in these cells treated with anti-CD38(-) SLE plasmas, or Normal plasmas. This effect did not occur in CD38-negative Jurkat T cells, suggesting that it could be attributed to anti-CD38 autoantibodies. These results support the hypothesis that anti-CD38 IgG autoantibodies or their associated plasma factors may dampen immune activation by affecting the viability of CD38(+) effector T cells and may provide protection from certain clinical SLE features.
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Multiwavelength transmission spectroscopy revisited for the characterization of the protein and polystyrene nanoparticle interactions.
Appl Spectrosc
PUBLISHED: 01-16-2013
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Multiwavelength transmission ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy is an effective technique that has not yet been fully exploited for the characterization of products of protein and particle interactions. Here, it is explored by using bovine serum albumin and National Institute of Standards and Technology-traceable particle size standard having a nominal diameter of 20 nm. Adsorption of bovine serum albumin to the particles is quantitatively ascertained through its effect on the wavelength-dependent transmission spectra of protein and particle mixtures. The experimental results demonstrate that the changes induced in the transmission spectra of protein and particle mixtures because of protein adsorption on particles are detectable and consistent with the expectations set by the light-scattering theory. The size, structure, composition, and relative concentrations of the particle populations present in the protein-particle mixtures can be quantified. Given the considerable dynamic range of multiwavelength transmission UV-Vis-NIR spectroscopy for particle analysis and its real-time measurement capabilities, this type of spectroscopy can be effectively used for the characterization of the products of protein-particle interaction and for the continuous real-time monitoring of interaction processes.
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Emergence and phylodynamics of Citrus tristeza virus in Sicily, Italy.
PLoS ONE
PUBLISHED: 01-01-2013
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Citrus tristeza virus (CTV) outbreaks were detected in Sicily island, Italy for the first time in 2002. To gain insight into the evolutionary forces driving the emergence and phylogeography of these CTV populations, we determined and analyzed the nucleotide sequences of the p20 gene from 108 CTV isolates collected from 2002 to 2009. Bayesian phylogenetic analysis revealed that mild and severe CTV isolates belonging to five different clades (lineages) were introduced in Sicily in 2002. Phylogeographic analysis showed that four lineages co-circulated in the main citrus growing area located in Eastern Sicily. However, only one lineage (composed of mild isolates) spread to distant areas of Sicily and was detected after 2007. No correlation was found between genetic variation and citrus host, indicating that citrus cultivars did not exert differential selective pressures on the virus. The genetic variation of CTV was not structured according to geographical location or sampling time, likely due to the multiple introduction events and a complex migration pattern with intense co- and re-circulation of different lineages in the same area. The phylogenetic structure, statistical tests of neutrality and comparison of synonymous and nonsynonymous substitution rates suggest that weak negative selection and genetic drift following a rapid expansion may be the main causes of the CTV variability observed today in Sicily. Nonetheless, three adjacent amino acids at the p20 N-terminal region were found to be under positive selection, likely resulting from adaptation events.
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Genetic variability and evolutionary dynamics of viruses of the family Closteroviridae.
Front Microbiol
PUBLISHED: 01-01-2013
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RNA viruses have a great potential for genetic variation, rapid evolution and adaptation. Characterization of the genetic variation of viral populations provides relevant information on the processes involved in virus evolution and epidemiology and it is crucial for designing reliable diagnostic tools and developing efficient and durable disease control strategies. Here we performed an updated analysis of sequences available in Genbank and reviewed present knowledge on the genetic variability and evolutionary processes of viruses of the family Closteroviridae. Several factors have shaped the genetic structure and diversity of closteroviruses. (I) A strong negative selection seems to be responsible for the high genetic stability in space and time for some viruses. (2) Long distance migration, probably by human transport of infected propagative plant material, have caused that genetically similar virus isolates are found in distant geographical regions. (3) Recombination between divergent sequence variants have generated new genotypes and plays an important role for the evolution of some viruses of the family Closteroviridae. (4) Interaction between virus strains or between different viruses in mixed infections may alter accumulation of certain strains. (5) Host change or virus transmission by insect vectors induced changes in the viral population structure due to positive selection of sequence variants with higher fitness for host-virus or vector-virus interaction (adaptation) or by genetic drift due to random selection of sequence variants during the population bottleneck associated to the transmission process.
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Differences in portal flow rates of amino acids and liver composition between rats fed casein or lactalbumin.
Arch Anim Nutr
PUBLISHED: 10-01-2011
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The portal appearance rates and net rates of amino acids absorption were studied in rats fed semi-synthetic diets containing either casein or lactalbumin (CAS and LA, respectively) as the only protein sources. Rats were pre-adapted to the experimental diets for 5 days prior to the absorption studies. Rats fed the LA diet had higher (p < 0.05) portal vein concentrations of free essential amino acids than those fed the CAS diet at 0, 60, 105 and 150 min after feeding. Portal and arterial concentrations of arginine, leucine, tryptophan, lysine and methionine were higher (p < 0.05) in rats fed LA at most time points tested, while concentrations of tyrosine were higher (p < 0.05) in CAS fed rats. When portal flow rates were compared, values for arginine, threonine, alanine, leucine, tryptophan and lysine were higher (p < 0.05) in LA at most time points tested, while proline, tyrosine and valine were higher (p < 0.05) for CAS fed rats after 60 and 105 min feeding. Portal blood flow varied (p < 0.05) with time in rats fed protein-free or LA diets, and was higher (p < 0.05) than that of CAS at 105 min. Intestinal net rates of absorption of tyrosine, valine, leucine and lysine were higher (p < 0.05) for LA fed rats as compared to those fed CAS at most time points tested, while alanine and proline net rates were higher (p < 0.05) for CAS fed rats at 60, 105 and 150 min. Amounts of protein in stomach contents of rats fed the CAS diet were significantly higher (p < 0.05) than those in LA fed rats at 60, 105 and 150 min after feeding. The relative liver weight of the rats fed the CAS diet was lower (p < 0.05) than that of animals fed the LA diet. Lower (p < 0.05) liver glycogen and lipid contents were determined in rats fed CAS diet respect to LA or protein-free fed rats. Results indicate that dietary and plasma amino acids profile are only partially related, and that under normal feeding conditions amino acids from CAS and LA are absorbed at different rates, which is likely to affect liver composition and metabolism.
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Increased expression and phosphorylation of the two S100A9 isoforms in mononuclear cells from patients with systemic lupus erythematosus: a proteomic signature for circulating low-density granulocytes.
J Proteomics
PUBLISHED: 07-19-2011
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Proteins differentially expressed in peripheral blood mononuclear cells (PBMCs) from systemic lupus erythematosus (SLE) patients versus Normal controls were identified by 2-DE and MALDI-MS. Thus, S100A9 expression was significantly increased in SLE PBMCs relative to Normal PBMCs at both mRNA and protein levels. Increased S100A9 levels in SLE PBMCs correlated positively with the abnormal presence of low-density granulocytes (LDGs) detected by flow-cytometry in the mononuclear cell fractions. Another set of proteins that were differentially expressed in SLE PBMCs formed S100A9-independent clusters, suggesting that these differences in protein expression are in fact reflecting changes in the abundance of specific cell types. In SLE PBMCs spots of the two S100A9 isoforms, S100A9-l and S100A9-s, and their phosphorylated counterparts were identified and confirmed to be phosphorylated at Thr(113) by MS/MS analyses. In addition, the phorbol ester PMA alone or in combination with ionomycin induced a stronger increase in threonine phosphorylation of S100A9 in SLE than in Normal PBMCs, while the same stimuli caused the opposite effect on phosphorylation and activation of Erk1/2, suggesting the existence of an abnormal S100A9 signaling in SLE PBMCs. Therefore, the expansion and activation of LDGs in SLE seems to underlie this prominent S100A9 signature.
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Otolaryngologic manifestations of systemic vasculitis.
Acta Otorrinolaringol Esp
PUBLISHED: 07-19-2011
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Systemic vasculitis is a heterogeneous group of diseases of various aetiologies and manifestations. In general, the clinical results derive from ischemia caused by vascular inflammation, which depends on the organ affected. Such vasculitis cases are classified according to the classification of the Chapel Hill conference. They can present with relative frequency as ENT manifestations in both their debut and throughout their evolution. Consequently, the ENT specialist should include them in the differential diagnosis in patients with ENT manifestations that are difficult to control or of atypical presentation. Our objective was to review the most common ENT clinical signs and symptoms in each of these diseases.
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Epidemiology and treatment of adenoid cystic carcinoma of the minor salivary glands: a meta-analytic study.
Med Oral Patol Oral Cir Bucal
PUBLISHED: 07-15-2011
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To evaluate the epidemiological aspects of adenoid cystic carcinoma (ACC) and to evaluate the different therapeutic possibilities as well as the percentage of survival.
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A de novo complete BRCA1 gene deletion identified in a Spanish woman with early bilateral breast cancer.
BMC Med. Genet.
PUBLISHED: 06-14-2011
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Germline mutations in either of the two tumor-suppressor genes, BRCA1 and BRCA2, account for a significant proportion of hereditary breast and ovarian cancer cases. Most of these mutations consist of deletions, insertions, nonsense mutations, and splice variants, however an increasing number of large genomic rearrangements have been identified in these genes.
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Hypochromicity in red blood cells: an experimental and theoretical investigation.
Biomed Opt Express
PUBLISHED: 05-26-2011
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Multiwavelength UV-visible transmission spectrophotometry is a useful tool for the examination of micron-size particle suspensions in the context of particle size and chemical composition. This paper reports the reliability of this method to characterize the spectra of purified red blood cells both in their physiological state and with modified hemoglobin content. Previous studies have suggested the contribution of hypochromism on the particle spectra caused by the close electronic interaction of the encapsulated chromophores. Our research shows, however, that this perceived hypochromism can be accounted for by considering two important issues: the acceptance angle of the instrument and the combined scattering and absorption effect of light on the particles. In order to establish these ideas, spectral analysis was performed on purified and modified red cells where the latter was accomplished with a modified hypotonic shock protocol that altered the hemoglobin concentration within the cells. Moreover, the Mie theory was used to successfully simulate the spectral features and trends of the red cells. With this combination of experimental and theoretical exploration, definition of hypochromism has been extended to two subcategories.
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Cohesive strength of nanocrystalline ZnO:Ga thin films deposited at room temperature.
Nanoscale Res Lett
PUBLISHED: 04-07-2011
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In this study, transparent conducting nanocrystalline ZnO:Ga (GZO) films were deposited by dc magnetron sputtering at room temperature on polymers (and glass for comparison). Electrical resistivities of 8.8 × 10-4 and 2.2 × 10-3 ? cm were obtained for films deposited on glass and polymers, respectively. The crack onset strain (COS) and the cohesive strength of the coatings were investigated by means of tensile testing. The COS is similar for different GZO coatings and occurs for nominal strains approx. 1%. The cohesive strength of coatings, which was evaluated from the initial part of the crack density evolution, was found to be between 1.3 and 1.4 GPa. For these calculations, a Youngs modulus of 112 GPa was used, evaluated by nanoindentation.
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Jumping to conclusions in psychosis: a faulty appraisal.
Schizophr. Res.
PUBLISHED: 04-02-2011
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Schizophrenia patients, particularly those with current delusions, show a cognitive bias known as jumping to conclusions, defined as a decision made quickly on the basis of little evidence. The aim of this work was to examine the underlying mechanisms of this cognitive bias by means of the Picture To Decision Task, which allows one to analyse the effect of the context on decisions made. We compared the performance of this task by 42 psychotic patients, 21 siblings of these patients and 77 controls. The results of the current study suggest that, relative to siblings and controls, patients display a general tendency to jump to conclusions, characterised by overestimating the conviction in their choices at the beginning of the decision process and by a lowered threshold for making decisions in ambiguous contexts, where a greater amount of information is required. These results are interpreted in terms of faulty appraisal, which would be the first mechanism responsible for the Jumping To Conclusions bias. Theoretical and clinical implications are discussed.
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Genetic variation and evolutionary analysis of broad bean wilt virus 2.
Arch. Virol.
PUBLISHED: 03-21-2011
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The genetic variation and evolutionary mechanisms of broad bean wilt virus 2 (BBWV-2) were studied by nucleotide sequence analysis of four genomic regions of 30 isolates from different countries. Nucleotide diversity was high (0.198) for a plant virus. Phylogenetic and genetic structure analyses showed low population subdivision, suggesting a significant gene flow between distant geographic areas. Analysis of synonymous and nonsynonymous substitutions showed different negative selection pressures for different parts of the coding regions, but no positive selection was found. Several recombination detection methods showed that some BBWV-2 genomes might have originated from recombination or reassortment.
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NifB and NifEN protein levels are regulated by ClpX2 under nitrogen fixation conditions in Azotobacter vinelandii.
Mol. Microbiol.
PUBLISHED: 01-25-2011
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The major part of biological nitrogen fixation is catalysed by the molybdenum nitrogenase that carries at its active site the iron and molybdenum cofactor (FeMo-co). The nitrogen fixation (nif) genes required for the biosynthesis of FeMo-co are derepressed in the absence of a source of fixed nitrogen. The nifB gene product is remarkable because it assembles NifB-co, a complex cluster proposed to comprise a [6Fe-9S-X] cluster, from simpler [Fe-S] clusters common to other metabolic pathways. NifB-co is a common intermediate of the biosyntheses of the cofactors present in the molybdenum, vanadium and iron nitrogenases. In this work, the expression of the Azotobacter vinelandii nifB gene was uncoupled from its natural nif regulation to show that NifB protein levels are lower in cells growing diazotrophically than in cells growing at the expense of ammonium. A. vinelandii carries a duplicated copy of the ATPase component of the ubiquitous ClpXP protease (ClpX2), which is induced under nitrogen fixing conditions. Inactivation of clpX2 resulted in the accumulation of NifB and NifEN and a defect in diazotrophic growth, especially when iron was in short supply. Mutations in nifE, nifN and nifX or in nifA also affected NifB accumulation, suggesting that NifB susceptibility to degradation might vary during its catalytic cycle.
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Molecular diagnosis of dermatofibrosarcoma protuberans: a comparison between reverse transcriptase-polymerase chain reaction and fluorescence in situ hybridization methodologies.
Genes Chromosomes Cancer
PUBLISHED: 01-24-2011
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Dermatofibrosarcoma protuberans (DFSP) is characterized by the presence of the t(17;22)(q22;q13) that leads to the fusion of the COL1A1 and PDGFB genes. This translocation can be detected by multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) or fluorescence in situ hybridization (FISH) techniques. We have evaluated the usefulness of a dual color dual fusion FISH probe strategy for COL1A1/PDGFB detection in a series of 103 archival DFSPs and compared the obtained results with RT-PCR analyses. FISH and RT-PCR were carried out on paraffin embedded tissue samples. Regarding the RT-PCR approach, all COL1A1 exons and exon 2 of PDGFB were evaluated. Sensitivity, specificity, positive and negative predictive values were assessed considering the histological diagnosis as the gold standard. We also analyzed the relationship between the genetic findings and the clinicopathological variables of the tumors. The COL1A1/PDGFB translocation was detected in 93% of DFSP. Both techniques showed a similar specificity (100%), but FISH was more sensitive than RT-PCR (90% vs. 72%). Regarding, clinicopathological features, a higher percentage of positive cells detected by FISH was significantly associated with the fibrosarcomatous DFSP variant (P < 0.001). Interestingly, all CD34 negative DFSP (n = 5) were positive for COL1A1/PDGFB translocation by both techniques. In conclusion, the majority of DFSP harbor the COL1A1/PDGFB translocation and FISH technique should be recommended as a routine diagnostic tool, especially in cases showing unusual histopathological subtypes and/or immunohistochemical features.
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[Evaluation of bone mineral density, bone turnover markers, the OPG/RANKL system and sTNF-RI in Crohns disease].
Gastroenterol Hepatol
PUBLISHED: 01-08-2011
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Patients with Crohns disease are at risk of developing osteoporosis, a disease in which the inflammatory process seems to be gaining importance. We performed a cross-sectional study to evaluate bone metabolism, osteoclastogenic factors [receptor activator of NF-kB ligand (RANK-L) and osteoprotegerin (OPG)] and soluble tumor necrosis factor-? receptor I (sTNF-RI) in patients with Crohns disease and to correlate the findings with the degree of disease activity.
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A sterile alpha-motif domain in NafY targets apo-NifDK for iron-molybdenum cofactor delivery via a tethered domain.
J. Biol. Chem.
PUBLISHED: 12-14-2010
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NafY participates in the final steps of nitrogenase maturation, having a dual role as iron-molybdenum cofactor (FeMo-co) carrier and as chaperone to the FeMo-co-deficient apo-NifDK (apo-dinitrogenase). NafY contains an N-terminal domain of unknown function (n-NafY) and a C-terminal domain (core-NafY) necessary for FeMo-co binding. We show here that n-NafY and core-NafY have very weak interactions in intact NafY. The NMR structure of n-NafY reveals that it belongs to the sterile ?-motif (SAM) family of domains, which are frequently involved in protein-protein interactions. The presence of a SAM domain in NafY was unexpected and could not be inferred from its amino acid sequence. Although SAM domains are very commonly found in eukaryotic proteins, they have rarely been identified in prokaryotes. The n-NafY SAM domain binds apo-NifDK. As opposed to full-length NafY, n-NafY impaired FeMo-co insertion when present in molar excess relative to FeMo-co and apo-NifDK. The implications of these observations are discussed to offer a plausible mechanism of FeMo-co insertion. NafY domain structure, molecular tumbling, and interdomain motion, as well as NafY interaction with apo-NifDK are consistent with the function of NafY in FeMo-co delivery to apo-NifDK.
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Attentional network task performance in schizophrenic patients.
Psicothema
PUBLISHED: 11-04-2010
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Several studies have researched the attentional functioning of schizophrenic patients by means of the Attentional Network Test. The present work reviews these studies and assesses the clinical relevance of their results. Both the reviewed data and our own results suggest that the Attentional Network Test does not provide a clear-cut discrimination of the attentional profile of schizophrenic patients from a clinical point of view. However, after classifying patients according to their psychotic symptoms, it became evident that positive syndrome patients are less efficient at tasks that tap the orientation network.
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Clinical implications of KIT and PDGFRA genotyping in GIST.
Clin Transl Oncol
PUBLISHED: 10-16-2010
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Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. GISTs are characterised by the expression of KIT, a type III tyrosine kinase receptor, and the presence of mutations in KIT or PDGFRA in about 80-85% of cases. The primary treatment for GIST is surgery, which cures most patients with low- or intermediate-risk tumours. The introduction of the kinase inhibitor imatinib mesylate, and sunitinib in second line, against KIT and PDGFRA has provided the first evidence of directed therapy in GIST. The aim of this review is to highlight the growing evidence that KIT and PDGFRA genotyping provides valuable information for the clinical management of GIST patients. We show that KIT and PDGFRA genotyping has emerged as one of the principal factors in the evaluation of GISTs, particularly in those tumours that are clearly malignant or have a high risk of recurrence. In addition to helping establish the diagnosis of GIST in unusual cases, genotyping can be very useful to physicians and patients in deciding on imatinib dose, in estimating the likelihood and duration of benefit, and potentially in selecting second-line therapies.
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Analysis of the subchondral microarchitecture of the distopalmar aspect of the third metacarpal bone in racing Thoroughbreds.
Am. J. Vet. Res.
PUBLISHED: 10-06-2010
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To determine the anisotropic characteristics of the microarchitecture of the subchondral bone (SCB) plate and trabecular bone (TBB) of the distopalmar aspect of the metacarpal condyles in horses with different stages of SCB disease.
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Evolutionary analysis of tomato Sw-5 resistance-breaking isolates of Tomato spotted wilt virus.
J. Gen. Virol.
PUBLISHED: 09-29-2010
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Tomato spotted wilt virus (TSWV) causes severe economic losses in many crops worldwide and often overcomes resistant cultivars used for disease control. Comparison of nucleotide and amino acid sequences suggested that tomato resistance conferred by the gene Sw-5 can be overcome by the amino acid substitution C to Y at position 118 (C118Y) or T120N in the TSWV movement protein, NSm. Phylogenetic analysis revealed that substitution C118Y has occurred independently three times in the studied isolates by convergent evolution, whereas the substitution T120N was a unique event. Analysis of rates of non-synonymous and synonymous changes at individual codons showed that substitution C118Y was positively selected.
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Modeling and interpretation of extinction spectra of oriented nonspherical composite particles: application to biological cells.
Appl Opt
PUBLISHED: 08-11-2010
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The majority of cells and microorganisms have a nonspherical shape and complex structure that challenge the interpretation of their spectral features. To address this issue, two approximations to the core-shell Mie theory were proposed. These included the approximation of light extinction by an ellipsoid with representation of the extinction by an equivalent sphere and representation of the extinction by a population of ellipsoidal particles with those of two weighted particle orientations. These hypotheses were first tested through numerical interpretation of the theoretical extinction spectra of prolate nucleated ellipsoids mimicking biological cells generated with anomalous diffraction approximation used as a reference method. Theoretical cases of fixed and random particle orientations demonstrated excellent capabilities of the proposed approach to retrieve the size, shape, and composition parameters of the model particles. Second, the UV-visible spectra of Leishmania species, promastigotes, elongated cells with prominent nuclei, were interpreted. The retrieved estimates of the protozoa size, shape, nucleus size, and nucleotide composition were in agreement with the corresponding microscopy estimates and literature values. Both theoretical tests and experimental results illustrated that the proposed approach can be successfully applied to estimate the structural and compositional parameters of cells from spectroscopic measurements.
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Quantitative analysis of morphological alterations in Plasmodium falciparum infected red blood cells through theoretical interpretation of spectral measurements.
J. Theor. Biol.
PUBLISHED: 07-29-2010
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Spectroscopic analysis can provide valuable insights into morphological and biochemical cellular transformations caused by diseases. However, traditional spectroscopic methods and the corresponding spectral interpretation approaches have been challenged by the complexities of the cell shape, orientation, and internal structure. Here we present an elegant spectral interpretation model that enables accurate quantitative analysis of the UV-visible spectra of red blood cells (RBCs) parasitized by the lethal human malaria parasite, Plasmodium falciparum. The model is based on the modified Mie theory (MMT) approach that incorporates the effects of the nonsphericity and orientation and multilayered cell structure to account for complex composition of the infected RBCs (IRBCs). We determine the structure and composition of the IRBCs and address unresolved matters over the alterations induced by the intraerythrocytic development of P. falciparum. The results indicate deformation and swelling of the IRBCs during the trophozoite stage of P. falciparum that is followed by substantial shrinkage during the schizont stages. We determine that up to 90% depletion of hemoglobin from the RBC cytosol does not lead to a net loss of iron from the infected cells. We quantitatively follow the morphological changes in the parasites during the intraerythrocytic development by applying the interpretation model to the UV-visible spectroscopic measurements of the IRBCs. We expect this method of quantitative spectroscopic characterization of the diseased cells to have practical clinical utility for rapid diagnosis, therapeutic monitoring, and drug susceptibility testing.
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A multiplex real-time PCR method for quantification of BK and JC polyomaviruses in renal transplant patients.
Diagn. Mol. Pathol.
PUBLISHED: 05-27-2010
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Infection of BK or JC human polyomavirus can lead to polyomavirus-associated nephropathy in renal transplant patients. Thus effective management of these patients requires early detection and quantification of these viruses in urine and blood.
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Long-term evolution of cytophagic histiocytic panniculitis.
J Cutan Med Surg
PUBLISHED: 05-22-2010
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Cytophagic histiocytic panniculitis is a disorder manifested by multiple subcutaneous nodules, characterized by lobular panniculitis, and occasionally accompanied by severe systemic manifestations, which require an aggressive medical approach. Several case reports with a good response to immunosuppressive therapy in the acute phase can be found in the literature.
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Clinical implications of TMPRSS2-ERG gene fusion expression in patients with prostate cancer treated with radical prostatectomy.
J. Urol.
PUBLISHED: 03-19-2010
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Molecular prognostic factors may be useful tools for prostate cancer that complement classic clinicopathological factors. Genetic rearrangements between TMPRSS2 and ETS have been described for prostate cancer but their clinical significance is still unclear. We analyzed the association of the TMPRSS2-ERG fusion gene with prostate cancer outcome in patients treated with radical prostatectomy.
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[Vitamin D deficiency and bone mineral density in Crohns disease].
Med Clin (Barc)
PUBLISHED: 02-20-2010
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Inadequate serum levels of 25-hydroxyvitamin D (25OHD(3)) are deemed as a possible risk factor for osteoporosis in Crohns disease (CD). Our aim is to determine the prevalence of inadequate serum levels of 25OHD(3) and its possible relationship with low bone mineral disease (BMD) in CD.
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Interpretation of the ultraviolet-visible spectra of malaria parasite Plasmodium falciparum.
Appl Opt
PUBLISHED: 01-12-2010
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The absorption and scattering properties of three developmental stages of protozoan parasite Plasmodium falciparum were studied both experimentally and theoretically. Experimentally, the light attenuation and forward scattering from parasites extracted from host erythrocyte cultures were measured with UV-visible spectroscopy. The measured spectra were interpreted theoretically with a model based on the core-shell Mie theory in terms of the structural and compositional characteristics of the protozoa. The model accurately reproduced the features of the measured spectra of all developmental stages. The results show that realistic quantitative estimates of the parasite size, nucleotide, and hemozoin contents can be derived from the UV-visible spectroscopy measurements.
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Substrate specificity and evolutionary implications of a NifDK enzyme carrying NifB-co at its active site.
FEBS Lett.
PUBLISHED: 01-08-2010
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The in vitro reconstitution of molybdenum nitrogenase was manipulated to generate a chimeric enzyme in which the active site iron-molybdenum cofactor (FeMo-co) is replaced by NifB-co. The NifDK/NifB-co enzyme was unable to reduce N(2) to NH(3), while exhibiting residual C(2)H(4) and considerable H(2) production activities. Production of H(2) by NifDK/NifB-co was stimulated by N(2) and was dependent on NifH and ATP hydrolysis. Thus, NifDK/NifB-co is a useful tool to gain insights into the catalytic mechanism of nitrogenase. Furthermore, phylogenetic analysis of D and K homologs indicates that several early emerging lineages, which contain NifB, NifH and NifDK encoding genes but which lack other genes required for processing NifB-co into FeMo-co, might encode an enzyme with similar catalytic properties to NifDK/NifB-co.
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Tongue infarction as first symptom of temporal arteritis.
Rheumatol. Int.
PUBLISHED: 01-08-2010
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Giant cell arteritis (GCA) is the most common systemic vasculitis affecting people over 50 years. This disease is a diagnostic challenge with a range of clinical symptoms and findings due to different affected vessels. Because of this, the initial diagnosis can be tricky, and some of the patients present at first time with a real unusual initial manifestation. One of these can be tongue necrosis, which is according to the literature in accordance with scalp necrosis, the rarest initial manifestation of GCA We describe a patient who presented with tongue necrosis as initial symptom of GCA. The belated diagnose resulted in subtotal necrosis of the mobile part of the tongue.
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Molybdenum trafficking for nitrogen fixation.
Biochemistry
PUBLISHED: 09-24-2009
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The molybdenum nitrogenase is responsible for most biological nitrogen fixation, a prokaryotic metabolic process that determines the global biogeochemical cycles of nitrogen and carbon. Here we describe the trafficking of molybdenum for nitrogen fixation in the model diazotrophic bacterium Azotobacter vinelandii. The genes and proteins involved in molybdenum uptake, homeostasis, storage, regulation, and nitrogenase cofactor biosynthesis are reviewed. Molybdenum biochemistry in A. vinelandii reveals unexpected mechanisms and a new role for iron-sulfur clusters in the sequestration and delivery of molybdenum.
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Honey bee aggression supports a link between gene regulation and behavioral evolution.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-21-2009
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A prominent theory states that animal phenotypes arise by evolutionary changes in gene regulation, but the extent to which this theory holds true for behavioral evolution is not known. Because "nature and nurture" are now understood to involve hereditary and environmental influences on gene expression, we studied whether environmental influences on a behavioral phenotype, i.e., aggression, could have evolved into inherited differences via changes in gene expression. Here, with microarray analysis of honey bees, we show that aggression-related genes with inherited patterns of brain expression are also environmentally regulated. There were expression differences in the brain for hundreds of genes between the highly aggressive Africanized honey bee compared with European honey bee (EHB) subspecies. Similar results were obtained for EHB in response to exposure to alarm pheromone (which provokes aggression) and when comparing old and young bees (aggressive tendencies increase with age). There was significant overlap of the gene lists generated from these three microarray experiments. Moreover, there was statistical enrichment of several of the same cis regulatory motifs in promoters of genes on all three gene lists. Aggression shows a remarkably robust brain molecular signature regardless of whether it occurs because of inherited, age-related, or environmental (social) factors. It appears that one element in the evolution of different degrees of aggressive behavior in honey bees involved changes in regulation of genes that mediate the response to alarm pheromone.
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New method for the detection of micro-organisms in blood: application of quantitative interpretation model to aerobic blood cultures.
J Biomed Opt
PUBLISHED: 07-02-2009
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The physical and chemical changes occurring in blood that has been inoculated into a blood culture bottle can be used as means to detect the presence of microorganisms in blood cultures. These changes include primarily the conversion of oxy- to deoxyhemoglobin within the red blood cells (RBCs) and changes in the cell number densities. These changes in the physical and chemical properties of blood can be readily detected using spectrophometric methods thus enabling the continuous monitoring of blood culture vials to provide quantitative information on the growth behavior of the microorganisms present. This paper reports on the application of spectrophotometric information obtained from diffuse reflectance measurements of aerobic blood cultures to detect microbial growth and compares the results to those obtained using the standard blood culture system.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.