1000 resultados para samário-153


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New geochronological data which clarify the timing of syn-orogenic magmatism and regional metamorphism in the Connemara Dalradian are presented. U-Pb zircon data on four intermediate to acid foliated magmatic rocks show important inherited components but the most concordant fractions demonstrate that major magmatism continued until 465 Ma whereas the earliest, basic magmatism has been dated previously at 490 Ma; a fine-grained, fabric-cutting granite contains discordant zircons which also appear to be 465 Ma old. Are magmatism in Connemara therefore spanned a period of at least 25 Ma. Recent U-Pb data on titanite from central Connemara which gave a peak metamorphic age of 478 Ma are supplemented by U-Pb data on titanite and monazite from metamorphic veins in the east of Connemara which indicate that low-P, high-T regional metamorphism ism continued there to 465 Ma, i.e. at least 10 Ma later than in the central region dated previously. New Rb-Sr data on muscovites from coarse-grained segregations in different structural settings range from 475 to 435 Ma; in part this range probably also reflects differences in age from west to east, with three ages close to 455 Ma from the eastern area, which is also the site of the lowest pressure metamorphism. Thermal modelling indicates that at any one locality the duration of metamorphism was probably as little as 1-2 Ma. The new dates emphasize the complexity in the spatial and temporal distribution of high-level regional metamorphism caused by magmatic activity. The relatively simple overall distribution of mineral-appearance isograds revealed by regional mapping masks the complexity of a prolonged but punctuated metamorphic history related to multiple intrusions, primarily in the southern part of Connemara. The later stages of magmatic activity followed progressive uplift and erosion after the onset of magmatism, and were localized in the eastern part of the region.

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Initiated in 2001, the West Tarkio Creek Watershed Project has a proven track record of implementing an enormous amount of structural conservation practices. To date, over $925,000 has been spent to build 69 miles of terraces on 63 cooperators' land. The success of the Project was due in large part to the conservation ethic of the landowners to improve their farms, preserve the productivity of the land, and protect West Tarkio Creek. This has been made possible through funding from DSC Watershed Protection Funds (WSPF) which has provided $1,362,592 in cost share funds since 2001 but is has been severely limited in recent years due to shortages within the State’s budget. The original project goals called for the construction of 750,000 feet (142 miles) of terraces to effectively treat the watershed. In order to meet these goals and bring the project to a successful endpoint, another 153,000 feet (29 miles) remain to be constructed by the landowners with the help of the SWCD staff. Severe rain events in recent years have caused an enormous amount of damage throughout the region, these storms were helpful in identifying where watershed work remains to be completed. Scars on the landscape in the aftermath of the storms clearly etched out the specific location where additional practices are needed in addition to those proposed in the original project work plan. Project supporters are confident that the WIRB Program can unlock this potential and pave the way for what can become known as one of the most effective land treatment projects in Iowa.

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The objective of this work was to evaluate photoprotective mechanisms related to low positive temperatures in Coffea canephora (Conilon clones 02 and 153) and C. arabica ('Catucaí' IPR 102) genotypes, involved in cold temperature tolerance. To accomplish this, one-year-old plants were successively submitted to: temperature decrease of 0.5ºC day-1, from 25/20ºC to 13/8ºC; a three-day chilling cycle at 13/4ºC; and a recovery period of 14 days (25/20ºC). During the experiment, leaf gas exchange, chlorophyll a fluorescence and leaf photosynthetic pigment content were evaluated. Total activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and ribulose-5-phosphate kinase (Ru5PK) were quantified to measure the activity of photosynthesis key enzymes. All genotypes showed low temperature sensitivity, but displayed diverse cold impact and recovery capabilities regarding the photosynthetic-related parameters studied. Catucaí IPR 102 cultivar showed better ability to cope with cold stress than the Conilon clones, especially Conilon 02, and had full recovery of leaf gas exchange, fluorescence parameters, enzymatic activity, and higher contents of the photoprotective pigments zeaxanthin and lutein.

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O objetivo deste trabalho foi avaliar a performance de normas DRIS específicas ou gerais no diagnóstico do estado nutricional do cupuaçuzeiro (Theobroma grandiflorum), na Amazônia Sul-Ocidental. Amostras foliares de cupuaçu foram coletadas de 153 pomares comerciais, com idade entre 5 e 18 anos, cultivados em monocultivo ou em sistemas agroflorestais. Foram geradas normas DRIS específicas para cada sistema de produção e normas gerais, obtidas para o conjunto da população monitorada. Na obtenção das normas, foi considerada a relação nutricional entre N, P, K, Ca, Mg, Fe, Cu, Zn e Mn. A maioria das médias das relações bivariadas entre nutrientes e dos diagnósticos produzidos pelas normas DRIS específicas não diferiu em relação aos produzidos com o uso da norma DRIS genérica. Portanto, a avaliação do estado nutricional de cupuaçuzeiros pode ser realizada com o uso de normas DRIS genéricas, que independem do sistema de cultivo.

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O objetivo deste trabalho foi avaliar a diversidade de Hemerobiidae (Neuroptera) em cafeeiros, e suas relações com Leucoptera coffeella, Coccus sp., Planococcus sp., Oligonychus ilicis, Brevipalpus phoenicis, Aphis spiraecola e Toxoptera aurantii. As amostragens foram realizadas em Cravinhos, SP, entre maio de 2005 e abril de 2007. Os hemerobiídeos foram coletados com rede de varredura, armadilha de Möricke e armadilhas luminosas e, para a amostragem das presas, foram coletadas folhas de cafeeiro. Foram obtidos 882 exemplares de hemerobiídeos: Nusalala tessellata (467 espécimes, 52,9% do total coletado), Hemerobius bolivari (153, 17,3%), Megalomus impudicus (114, 12,9%), Sympherobius miranda (109, 12,4%), Megalomus rafaeli (30, 3,4%), Sympherobius ariasi (6, 0,7%) e Nomerobius psychodoides (3, 0,3%). A ocorrência de Nusalala tessellata e M. impudicus foi correlacionada positivamente à de Coccus sp.; o mesmo fato ocorreu para M. rafaeli com lagartas de L. coffeella e A. spiraecola e para H. bolivari com O. ilicis. As correlações foram negativas e significativas entre as ocorrências de S. miranda e O. ilicis e entre as de N. tessellata e L. coffeella e O. ilicis. As correlações mostraram que os Hemerobiidae, predadores generalistas, foram favorecidos pelo constante suprimento de presas que ocorreram na cultura do café, no período estudado.

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Tissue protein hypercatabolism (TPH) is a most important feature in cancer cachexia, particularly with regard to the skeletal muscle. The rat ascites hepatoma Yoshida AH-130 is a very suitable model system for studying the mechanisms involved in the processes that lead to tissue depletion, since it induces in the host a rapid and progressive muscle waste mainly due to TPH (Tessitore, L., G. Bonelli, and F. M. Baccino. 1987. Biochem. J. 241:153-159). Detectable plasma levels of tumor necrosis factor-alpha associated with marked perturbations in the hormonal homeostasis have been shown to concur in forcing metabolism into a catabolic setting (Tessitore, L., P. Costelli, and F. M. Baccino. 1993. Br. J. Cancer. 67:15-23). The present study was directed to investigate if beta 2-adrenergic agonists, which are known to favor skeletal muscle hypertrophy, could effectively antagonize the enhanced muscle protein breakdown in this cancer cachexia model. One such agent, i.e., clenbuterol, indeed largely prevented skeletal muscle waste in AH-130-bearing rats by restoring protein degradative rates close to control values. This normalization of protein breakdown rates was achieved through a decrease of the hyperactivation of the ATP-ubiquitin-dependent proteolytic pathway, as previously demonstrated in our laboratory (Llovera, M., C. García-Martínez, N. Agell, M. Marzábal, F. J. López-Soriano, and J. M. Argilés. 1994. FEBS (Fed. Eur. Biochem. Soc.) Lett. 338:311-318). By contrast, the drug did not exert any measurable effect on various parenchymal organs, nor did it modify the plasma level of corticosterone and insulin, which were increased and decreased, respectively, in the tumor hosts. The present data give new insights into the mechanisms by which clenbuterol exerts its preventive effect on muscle protein waste and seem to warrant the implementation of experimental protocols involving the use of clenbuterol or alike drugs in the treatment of pathological states involving TPH, particularly in skeletal muscle and heart, such as in the present model of cancer cachexia.

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Tissue protein hypercatabolism (TPH) is a most important feature in cancer cachexia, particularly with regard to the skeletal muscle. The rat ascites hepatoma Yoshida AH-130 is a very suitable model system for studying the mechanisms involved in the processes that lead to tissue depletion, since it induces in the host a rapid and progressive muscle waste mainly due to TPH (Tessitore, L., G. Bonelli, and F. M. Baccino. 1987. Biochem. J. 241:153-159). Detectable plasma levels of tumor necrosis factor-alpha associated with marked perturbations in the hormonal homeostasis have been shown to concur in forcing metabolism into a catabolic setting (Tessitore, L., P. Costelli, and F. M. Baccino. 1993. Br. J. Cancer. 67:15-23). The present study was directed to investigate if beta 2-adrenergic agonists, which are known to favor skeletal muscle hypertrophy, could effectively antagonize the enhanced muscle protein breakdown in this cancer cachexia model. One such agent, i.e., clenbuterol, indeed largely prevented skeletal muscle waste in AH-130-bearing rats by restoring protein degradative rates close to control values. This normalization of protein breakdown rates was achieved through a decrease of the hyperactivation of the ATP-ubiquitin-dependent proteolytic pathway, as previously demonstrated in our laboratory (Llovera, M., C. García-Martínez, N. Agell, M. Marzábal, F. J. López-Soriano, and J. M. Argilés. 1994. FEBS (Fed. Eur. Biochem. Soc.) Lett. 338:311-318). By contrast, the drug did not exert any measurable effect on various parenchymal organs, nor did it modify the plasma level of corticosterone and insulin, which were increased and decreased, respectively, in the tumor hosts. The present data give new insights into the mechanisms by which clenbuterol exerts its preventive effect on muscle protein waste and seem to warrant the implementation of experimental protocols involving the use of clenbuterol or alike drugs in the treatment of pathological states involving TPH, particularly in skeletal muscle and heart, such as in the present model of cancer cachexia.

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Tissue protein hypercatabolism (TPH) is a most important feature in cancer cachexia, particularly with regard to the skeletal muscle. The rat ascites hepatoma Yoshida AH-130 is a very suitable model system for studying the mechanisms involved in the processes that lead to tissue depletion, since it induces in the host a rapid and progressive muscle waste mainly due to TPH (Tessitore, L., G. Bonelli, and F. M. Baccino. 1987. Biochem. J. 241:153-159). Detectable plasma levels of tumor necrosis factor-alpha associated with marked perturbations in the hormonal homeostasis have been shown to concur in forcing metabolism into a catabolic setting (Tessitore, L., P. Costelli, and F. M. Baccino. 1993. Br. J. Cancer. 67:15-23). The present study was directed to investigate if beta 2-adrenergic agonists, which are known to favor skeletal muscle hypertrophy, could effectively antagonize the enhanced muscle protein breakdown in this cancer cachexia model. One such agent, i.e., clenbuterol, indeed largely prevented skeletal muscle waste in AH-130-bearing rats by restoring protein degradative rates close to control values. This normalization of protein breakdown rates was achieved through a decrease of the hyperactivation of the ATP-ubiquitin-dependent proteolytic pathway, as previously demonstrated in our laboratory (Llovera, M., C. García-Martínez, N. Agell, M. Marzábal, F. J. López-Soriano, and J. M. Argilés. 1994. FEBS (Fed. Eur. Biochem. Soc.) Lett. 338:311-318). By contrast, the drug did not exert any measurable effect on various parenchymal organs, nor did it modify the plasma level of corticosterone and insulin, which were increased and decreased, respectively, in the tumor hosts. The present data give new insights into the mechanisms by which clenbuterol exerts its preventive effect on muscle protein waste and seem to warrant the implementation of experimental protocols involving the use of clenbuterol or alike drugs in the treatment of pathological states involving TPH, particularly in skeletal muscle and heart, such as in the present model of cancer cachexia.

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Many questions in evolutionary biology require an estimate of divergence times but, for groups with a sparse fossil record, such estimates rely heavily on molecular dating methods. The accuracy of these methods depends on both an adequate underlying model and the appropriate implementation of fossil evidence as calibration points. We explore the effect of these in Poaceae (grasses), a diverse plant lineage with a very limited fossil record, focusing particularly on dating the early divergences in the group. We show that molecular dating based on a data set of plastid markers is strongly dependent on the model assumptions. In particular, an acceleration of evolutionary rates at the base of Poaceae followed by a deceleration in the descendants strongly biases methods that assume an autocorrelation of rates. This problem can be circumvented by using markers that have lower rate variation, and we show that phylogenetic markers extracted from complete nuclear genomes can be a useful complement to the more commonly used plastid markers. However, estimates of divergence times remain strongly affected by different implementations of fossil calibration points. Analyses calibrated with only macrofossils lead to estimates for the age of core Poaceae ∼51-55 Ma, but the inclusion of microfossil evidence pushes this age to 74-82 Ma and leads to lower estimated evolutionary rates in grasses. These results emphasize the importance of considering markers from multiple genomes and alternative fossil placements when addressing evolutionary issues that depend on ages estimated for important groups.

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Background:Transplant glomerulopathy (TG) has received much attention in recent years as a manifestation of chronic humoral rejection (CHR). However, many cases lack C4d deposition and/or circulating donor-specifi c antibodies, and the contribution of other potential causes has not been fully addressed.Methods: Of 209 consecutive renal allograft indication biopsies performed for chronic allograft dysfunction, 25 that met pathologic criteria of TG (>10% duplication of the GBM without immune complex deposition) were examined for various etiologies, including hepatitis C infection (HCV), thrombotic microangiopathy (TMA), and CHR. 29 cases of biopsy-proven isolated chronic calcineurin inhibitor toxicity from the same time period were used as controls for comparing the prevalence of HCV.Results: Three partially overlapping categories accounted for 84% of the cases: C4d+TG (48%), HCV+TG (36%) and TMA+TG (32%). The majority of TMA+ cases were HCV+ (63%) and the majority of HCV+ cases had TMA (56%). Donor specifi c antibodies were associated with C4d+TG (7/8 vs. 1/4 C4d-TG; P<0.02), but not with HCV+TG. The prevalence of HCV was higher in the TG group than in 29 control patients without TG (36% vs. 7%, P<0.01). HCV+TG patients developed allograft failure earlier than HCV-TG patients (67.2 ± 60.2 mo versus 153.4 ± 126.2 mo, P=0.02). On a multivariate analysis, out of HCV, TG and C4d, only HCV was found to be a signifi cant risk factor for a more rapid allograft loss.Conclusion: We conclude that TG is not a specifi c diagnosis, but a pattern of pathologic injury with 3 major overlapping pathways involving CHR, HCV infection and TMA. It is important to distinguish these mechanisms, as they may have differentprognostic and therapeutic implications.

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Objectives: To assess the difference in direct medical costs between on-demand (OD) treatment with esomeprazole (E) 20 mg and continuous (C) treatment with E 20 mg q.d. from a clinical practice view in patients with gastroesophageal reflux disease (GERD) symptoms. Methods: This open, randomized study (ONE: on-demand Nexium evaluation) compared two long-term management options with E 20 mg in endoscopically uninvestigated patients seeking primary care for GERD symptoms who demonstrated complete relief of symptoms after an initial treatment of 4 weeks with E 40 mg. Data on consumed quantities of all cost items were collected in the study, while data on prices during the time of study were collected separately. The analysis was done from a societal perspective. Results: Forty-nine percent (484 of 991) of patients randomized to the OD regimen and 46% (420 of 913) of the patients in the C group had at least one contact with the investigator that would have occurred nonprotocol-driven. The difference of the adjusted mean direct medical costs between the treatment groups was CHF 88.72 (95% confidence interval: CHF 41.34-153.95) in favor of the OD treatment strategy (Wilcoxon rank-sum test: P < 0.0001). Adjusted direct nonmedical costs and productivity loss were similar in both groups. Conclusions: The adjusted direct medical costs of a 6-month OD treatment with esomeprazole 20 mg in uninvestigated patients with symptoms of GERD were significantly lower compared with a continuous treatment with E 20 mg once a day. The OD therapy represents a cost-saving alternative to the continuous treatment strategy with E.

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The novelties in clinical psychiatry are close to somatic medicine adaptation. The clinical staging concept in psychiatry (as in cancerology) is the result of an early intervention strategy in psychotic disorders. A differentiated mode of understanding of the phases of psychiatric disorders allows a prevention oriented approach. Individualized therapeutic programmes in accordance with specific problematics favors the orientation towards focalised follow-ups, for instance CBT programmes on Internet may be proposed to patients motivated and rather autonomous. Others, on the contrary, less accessible to health care should benefit of the support of a mobile team and specific coaching to return to vocational services. Systematic follow-up of the metabolic syndrome, often induced by atypical antipsychotics, belongs to those basic adjustment processes.

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BACKGROUND: Interferon and ribavirin therapy for chronic hepatitis C virus (HCV) infection yields sustained virological response (SVR) rates of 50-80%. Several factors such as non-1 genotype, beneficial IL28B genetic variants, low baseline IP-10, and the functionality of HCV-specific T cells predict SVR. With the pending introduction of new therapies for HCV entailing very rapid clearance of plasma HCV RNA, the importance of baseline biomarkers likely will increase in order to tailor therapy. CD26 (DPPIV) truncates the chemokine IP-10 into a shorter antagonistic form, and this truncation of IP-10 has been suggested to influence treatment outcome in patients with chronic HCV infection patients. In addition, previous reports have shown CD26 to be a co-stimulator for T cells. The aim of the present study was to assess the utility of CD26 as a biomarker for treatment outcome in chronic hepatitis C and to define its association with HCV-specific T cells. METHODS: Baseline plasma from 153 genotype 1 and 58 genotype 2/3 infected patients enrolled in an international multicenter phase III trial (DITTO-HCV) and 36 genotype 1 infected patients participating in a Swedish trial (TTG1) were evaluated regarding baseline soluble CD26 (sCD26) and the functionality of HCV-specific CD8(+) T cells. RESULTS: Genotype 1 infected patients achieving SVR in the DITTO (P = 0.002) and the TTG1 (P = 0.02) studies had lower pretreatment sCD26 concentrations compared with non-SVR patients. Sixty-five percent of patients with sCD26 concentrations below 600 ng/mL achieved SVR compared with 39% of the patients with sCD26 exceeding 600 ng/mL (P = 0.01). Patients with sCD26 concentrations below 600 ng/mL had significantly higher frequencies of HCV-specific CD8(+) T cells (P = 0.02). CONCLUSIONS: Low baseline systemic concentrations of sCD26 predict favorable treatment outcome in chronic HCV infection and may be associated with higher blood counts of HCV-specific CD8(+) T cells.

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El objetivo de este trabajo fue evaluar la influencia de la fertilización mineral nitrogenada, después de la poda del cafeto robusta, sobre la productividad del cultivo y algunos indicadores químicos (pH, materia orgánica) y microbiológicos (respiración biológica y nitrificación) de dos Cambisoles en Tercer Frente, Santiago de Cuba y La Alcarraza, Holguín, durante los años 2003-2007. Se estudió la respuesta a dosis crecientes de nitrógeno (0 hasta 400 kg ha-1), en presencia de un fondo fijo de P (50 kg ha-1) y K (160 kg ha-1), en un diseño experimental de bloques al azar, con cuatro réplicas. Para productividades entre 0,50 y 0,84 Mg ha-1 de café, son suficientes 75 kg ha-1 de N. Aplicaciones de 100 kg ha-1 de N permitieron productividades de 1,22 a 1,25 Mg ha-1de café. Con dosis de 153 kg ha-1 de N, se logran producciones de 1,80 Mg ha-1 de café, mientras que para productividades superiores a 2 Mg ha-1 se necesita aplicar 200 kg ha-1 en ambos suelos. Se encontró un incremento importante en las productividades del cafeto por cada quilogramo de N aplicado, que osciló entre 2,13 y 7,80. Las dosis propuestas por sitio no afectaron la actividad microbiana y la materia orgánica de los suelos. Se encontró disminución del pH del suelo respecto a su estado inicial.