992 resultados para PROTEOGLYCAN SYNTHESIS RATES


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Lipin 1 is a coregulator of DNA-bound transcription factors and a phosphatidic acid (PA) phosphatase (PAP) enzyme that catalyzes a critical step in the synthesis of glycerophospholipids. Lipin 1 is highly expressed in adipocytes, and constitutive loss of lipin 1 blocks adipocyte differentiation; however, the effects of Lpin1 deficiency in differentiated adipocytes are unknown. Here we report that adipocyte-specific Lpin1 gene recombination unexpectedly resulted in expression of a truncated lipin 1 protein lacking PAP activity but retaining transcriptional regulatory function. Loss of lipin 1-mediated PAP activity in adipocytes led to reduced glyceride synthesis and increased PA content. Characterization of the deficient mice also revealed that lipin 1 normally modulates cAMP-dependent signaling through protein kinase A to control lipolysis by metabolizing PA, which is an allosteric activator of phosphodiesterase 4 and the molecular target of rapamycin. Consistent with these findings, lipin 1 expression was significantly related to adipose tissue lipolytic rates and protein kinase A signaling in adipose tissue of obese human subjects. Taken together, our findings identify lipin 1 as a reciprocal regulator of triglyceride synthesis and hydrolysis in adipocytes, and suggest that regulation of lipolysis by lipin 1 is mediated by PA-dependent modulation of phosphodiesterase 4.

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Iowa Unemployment Rates by County map produced by the Iowa Workforce Development.

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The incidence of contralateral breast cancer is high and constant with age, around five per 1000 women who had a primary breast cancer. For other neoplasms, the pattern of incidence of second primary neoplasms with age is less known, particularly as for only a few neoplasms the site of origin is not totally removed, and hence remains at risk of a second primary. Using the dataset from the Cancer Registry of the Swiss Canton of Vaud, we show that the incidence of second neoplasms is constant with age also after oral and pharyngeal, colorectal cancers, cutaneous malignant melanoma (CMM) and basal cell carcinoma. The incidence of first primary oral and pharyngeal cancer increased 20-fold between age 30-39 and 70-89 years, whereas the incidence of second neoplasms did not increase with age. Rates of second colorectal cancer remained relatively constant with age, between 2.5 per 1000 at age 40-59 years and 3.8 per 1000 at 70 years and above. Likewise, for CMM, the age-specific incidence rates of second primary CMM did not vary, ranging between 1 and 2.5 per 1000 in various subsequent age groups. The pattern of incidence for second basal cell carcinoma was similar, with no clear rise with age. These patterns are compatible with the occurrence of a single mutational event in a population of susceptible individuals. A possible implication of these observations is that a variable, but potentially large, proportion of cancers arise in very high-risk individuals and the incidence, on average, increases at a high constant level at a predetermined age.

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Use of radiolabeled nucleotides for tumor imaging is hampered by rapid in vivo degradation and low DNA-incorporation rates. We evaluated whether blocking of thymidine (dThd) synthesis by 5-fluoro-2'-deoxyuridine (FdUrd) could improve scintigraphy with radio-dThd analogues, such as 5-iodo-2'-deoxyuridine (IdUrd). We first show in vitro that coincubation with FdUrd substantially increased incorporation of [125I]IdUrd and [3H]dThd in the three tested human glioblastoma lines. Flow cytometry analysis showed that a short coincubation with FdUrd (1 h) produces a signal increase per labeled cell. We then measured biodistribution 24 h after i.v. injection of [125I]IdUrd in nude mice s.c. xenografted with the three glioblastoma lines. Compared with animals given [125I]IdUrd alone, i.v. preadministration for 1 h of 10 mg/kg FdUrd increased the uptake of [125I]IdUrd in the three tumors 4.8-6.8-fold. Compatible with previous reports, there were no side effects in mice observed for 2 months after receiving such a treatment. The tumor uptake of [125I]IdUrd was increased < or =13.6-fold when FdUrd preadministration was stepwise reduced to 1.1 mg/kg. Uptake increases remained lower (between 1.7- and 5.8-fold) in normal proliferating tissues (i.e., bone marrow, spleen, and intestine) and negligible in quiescent tissues. DNA extraction showed that 72-80% of radioactivity in tumor and intestine was bound to DNA. Scintigraphy of xenografted mice was performed at different times after i.v. injection of 3.7 MBq [125I]IdUrd. Tumor detection was significantly improved after FdUrd preadministration while still equivocal after 24 h in mice given [125I]IdUrd alone. Furthermore, background activity could be greatly reduced by p.o. administration of KClO4 in addition to potassium iodide. We conclude that FdUrd preadministration may improve positron or single photon emission tomography with cell division tracers, such as radio-IdUrd and possibly other dThd analogues.

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Iowa Unemployment Rates by County map produced by the Iowa Workforce Development.

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Arginine-glycine-aspartic acid (RGD)-containing peptides have been traditionally used as PET probes to noninvasively image angiogenesis, but recently, small selective molecules for α5 β1 integrin receptor have been developed with promising results. Sixty-one antagonists were screened, and tert-butyl (S)-3-(2-((3R,5S)-1-(3-(1-(2-fluoroethyl)-1H-1,2,3-triazol-4-yl)propanoyl)-5-((pyridin-2-ylamino)methyl)pyrrolidin-3-yloxy)acetamido)-2-(2,4,6-trimethylbenzamido)propanoate (FPMt) was selected for the development of a PET tracer to image the expression of α5 β1 integrin receptors. An alkynyl precursor (PMt) was initially synthesized in six steps, and its radiolabeling was performed according to the azide-alkyne copper(II)-catalyzed Huisgen's cycloaddition by using 1-azido-2-[(18)F]fluoroethane ([(18)F]12). Different reaction conditions between PMt and [(18)F]12 were investigated, but all of them afforded [(18)F]FPMt in 15 min with similar radiochemical yields (80-83%, decay corrected). Overall, the final radiopharmaceutical ([(18)F]FPMt) was obtained after a synthesis time of 60-70 min in 42-44% decay-corrected radiochemical yield.

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Bioassays with bioreporter bacteria are usually calibrated with analyte solutions of known concentrations that are analysed along with the samples of interest. This is done as bioreporter output (the intensity of light, fluorescence or colour) does not only depend on the target concentration, but also on the incubation time and physiological activity of the cells in the assay. Comparing the bioreporter output with standardized colour tables in the field seems rather difficult and error-prone. A new approach to control assay variations and improve application ease could be an internal calibration based on the use of multiple bioreporter cell lines with drastically different reporter protein outputs at a given analyte concentration. To test this concept, different Escherichia coli-based bioreporter strains expressing either cytochrome c peroxidase (CCP, or CCP mutants) or β-galactosidase upon induction with arsenite were constructed. The reporter strains differed either in the catalytic activity of the reporter protein (for CCP) or in the rates of reporter protein synthesis (for β-galactosidase), which, indeed, resulted in output signals with different intensities at the same arsenite concentration. Hence, it was possible to use combinations of these cell lines to define arsenite concentration ranges at which none, one or more cell lines gave qualitative (yes/no) visible signals that were relatively independent of incubation time or bioreporter activity. The discriminated concentration ranges would fit very well with the current permissive (e.g. World Health Organization) levels of arsenite in drinking water (10 µg l−1).

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The 5-year "Solmobile" skin prevention campaigns carried out between 2001 and 2005 by the Swiss League against Cancer met their objectives. About 21'000 visits were recorded throughout Switzerland and 10'000 clinical skin examinations performed. This report briefly summarises the main results of the epidemiological evaluation of these campaigns.

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Reliable estimates of the post-release mortality probability of marine turtles after incidental by-catch are essential for assessing the impact of longline fishing on these species.Large numbers of loggerhead turtles Caretta caretta from rookeries in the northwestern Atlantic Ocean have been by-caught annually in the southwestern Mediterranean Sea since the 1980s, but nothing is known about their post-release mortality probability under natural conditions. Pop-up archival transmitting tags were attached to 26 loggerhead turtles following incidental capture by Spanish longliners. Hooks were not removed, and 40 cm of line was left in place. The post-release mortality probability during the 90 d following release ranged from 0.308 to 0.365, and was independent of hook location. When the post-release mortality probability was combined with previously reported estimates of the mortality probability before hauling, the aggregated by-catch mortality probability ranged from 0.321 to 0.378. Assuming a total annual by-catch of 10656 loggerhead turtles by the Spanish longline fleet operating in the southwestern Mediterranean, by-catch results in 3421 to 4028 turtle deaths annually. This range is equivalent to 8.5−10.1% of the approximately 40000 turtles inhabiting the fishing grounds used by Spanish longliners, most of them from rookeries in the northwestern Atlantic. As a consequence, the accumulated mortality during the oceanic stage is expected to be larger for those loggerhead turtles of Atlantic origin that spend several years in the Mediterranean Sea than for turtles of the same cohort that remain in the Atlantic. For this reason, the Mediterranean can be considered a dead end for loggerhead turtle populations nesting in the Atlantic, although the actual demographic relevance of by-catch mortality of loggerhead turtles in the Mediterranean remains unknown.

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Here we describe an approach to the expressive synthesis of jazz saxophone melodies that reuses audio recordings and carefully concatenates note samples. The aim is to generate an expressive audio sequence from the analysis of an arbitrary input score using a previously induced performance model and an annotated saxophone note database extracted from real performances. We push the idea of using the same corpus for both inducing an expressive performance model and synthesizing sound by concatenating samples in the corpus. Therefore, a connection between the performers’ instrument sound and performance characteristics is kept during the synthesis process.

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Excitation-continuous music instrument control patterns are often not explicitly represented in current sound synthesis techniques when applied to automatic performance. Both physical model-based and sample-based synthesis paradigmswould benefit from a flexible and accurate instrument control model, enabling the improvement of naturalness and realism. Wepresent a framework for modeling bowing control parameters inviolin performance. Nearly non-intrusive sensing techniques allow for accurate acquisition of relevant timbre-related bowing control parameter signals.We model the temporal contour of bow velocity, bow pressing force, and bow-bridge distance as sequences of short Bézier cubic curve segments. Considering different articulations, dynamics, and performance contexts, a number of note classes are defined. Contours of bowing parameters in a performance database are analyzed at note-level by following a predefined grammar that dictates characteristics of curve segment sequences for each of the classes in consideration. As a result, contour analysis of bowing parameters of each note yields an optimal representation vector that is sufficient for reconstructing original contours with significant fidelity. From the resulting representation vectors, we construct a statistical model based on Gaussian mixtures suitable for both the analysis and synthesis of bowing parameter contours. By using the estimated models, synthetic contours can be generated through a bow planning algorithm able to reproduce possible constraints caused by the finite length of the bow. Rendered contours are successfully used in two preliminary synthesis frameworks: digital waveguide-based bowed stringphysical modeling and sample-based spectral-domain synthesis.

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Iowa Unemployment Rates by County map produced by the Iowa Workforce Development.

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This paper presents a framework in which samples of bowing gesture parameters are retrieved and concatenated from a database of violin performances by attending to an annotated input score. Resulting bowing parameter signals are then used to synthesize sound by means of both a digital waveguide violin physical model, and an spectral-domainadditive synthesizer.

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The control and regrowth after nicosulfuron reduced rate treatment of Johnsongrass (Sorghum halepense L. Pers.) populations, from seven Argentinean locations, were evaluated in pot experiments to assess if differential performance could limit the design and implementation of integrated weed management programs. Populations from humid regions registered a higher sensibility to reduced rates of nicosulfuron than populations from subhumid regions. This effect was visualised in the values of regression coefficient of the non-linear models (relating fresh weight to nicosulfuron rate), and in the time needed to obtain a 50% reduction of photosynthesis rate and stomatal conductance. The least leaf CO2 exchange of subhumid populations could result in a lower foliar absorption and translocation of nicosulfuron, thus producing less control and increasing their ability to sprout and produce new aerial biomass. The three populations from subhumid regions, with less sensibility to nicosulfuron rates, presented substantial difference in fresh weight, total rhizome length and number of rhizome nodes, when they were evaluated 20 week after treatment. In consequence, a substantial Johnsongrass re-infestation could occur, if rates below one-half of nicosulfuron labeled rate were used to control Johnsongrass in subhumid regions.

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Iowa Unemployment Rates by County map produced by the Iowa Workforce Development.