958 resultados para dose time effect relation


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Diatraea saccharalis, is a major sugarcane pest, causing damage to the stalks of sugarcane plants. In this study, a trypsin inhibitor (ApTI) was purified from Adenanthera pavonina seeds and was tested for its insect growth regulatory effect. ApTI showed a dose-dependent effect on average larval weight and survival. 0.1% ApTI produced approximately 67% and 50% decreases in weight and survival larval, respectively. The results from dietary utilization experiments with D. saccharalis larvae showed a reduction in the efficiency of conversion of ingested food and digested food, and an increase in approximate digestibility and metabolic cost. The level of trypsin was significantly decreased (ca. 55%) in the midgut of larvae reared on a diet containing 0.05% ApTI and the trypsin activity in ApTI-fed larvae demonstrated sensitivity to ApTI. The action of ApTI on the development of D. saccharalis larvae shows that this protein may have great toxic potential. (C) 2011 Elsevier Ltd. All rights reserved.

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The purpose of present review is to describe the effect of leucine supplementation on skeletal muscle proteolysis suppression in both in vivo and in vitro studies. Most studies, using in vitro methodology, incubated skeletal muscles with leucine with different doses and the results suggests that there is a dose-dependent effect. The same responses can be observed in in vivo studies. Importantly, the leucine effects on skeletal muscle protein synthesis are not always connected to the inhibition of skeletal muscle proteolysis. As a matter of fact, high doses of leucine incubation can promote suppression of muscle proteolysis without additional effects on protein synthesis, and low leucine doses improve skeletal muscle protein ynthesis but have no effect on skeletal muscle proteolysis. These research findings may have an important clinical relevancy, because muscle loss in atrophic states would be reversed by specific leucine supplementation doses. Additionally, it has been clearly demonstrated that leucine administration suppresses skeletal muscle proteolysis in various catabolic states. Thus, if protein metabolism changes during different atrophic conditions, it is not surprising that the leucine dose-effect relationship must also change, according to atrophy or pathological state and catabolism magnitude. In conclusion, leucine has a potential role on attenuate skeletal muscle proteolysis. Future studies will help to sharpen the leucine efficacy on skeletal muscle protein degradation during several atrophic states.

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Die Analyse der Einflussfaktoren Kapselmaterial, Trägerlaktose, Additiv-Anteil, Mischreihenfolge und mechanische Belastung ergibt verschiedene Haupteinflussfaktoren und kombinierte Wechselwirkungen, die einen deutlichen Effekt auf die aerodynamischen Eigenschaften (ausgebrachte Dosis und Verteilung des aerodynamischen Feinanteils) haben. Sowohl das Kapselmaterial als auch die Trägerlaktose werden als primäre Einflussfaktoren identifiziert: Mit „inerten” PE-Kapseln lassen sich höhere Resultate erzielen als mit „adhäsiven” Gelatine-Kapseln, während „feines” Trägermaterial die Ausbringung stärker fördert, als „grobes“ Trägermaterial. Alles Faktoren, die sich in gleicher Weise auf die Verteilung des aerodynamischen Feinanteils auswirken. Der zur binären Mischung zugefügte Additiv-Anteil führt neben einem ausgeprägten kapselmaterialabhängigen Effekt auf die Höhe der ausgebrachten Dosis auch zu einer Steigerung in der Verteilung des aerodynamischen Feinanteils („Umhüllungseffekt”), was durch die Variation der Mischreihenfolge anschaulich nachgewiesen wird. Die anschließende detaillierte Charakterisierung der beobachteten Effekte auf Basis von Partikelmorphologie und Oberflächenstruktur der Kapseln führt zu einer Differenzierung in Partikel-Partikel-Wechselwirkungen (z.B. „Umhüllungseffekt”, „Multiplets“) und Partikel-Kapsel- Wechselwirkungen (z.B. „Auspudereffekt”). Durch Entwicklung von analytischen Verfahren wird eine Quantifizierung der Trägerlaktose möglich, was für den Nachweis einer positiven Korrelation zwischen den aerodynamischen Eigenschaften von Wirkstoff und Trägerlaktose notwendig ist. Sowohl für die ausgebrachte Dosis als auch für die Verteilung des aerodynamischen Feinanteils zeigt sich ein parallel verlaufender Anstieg der Ergebnisse.

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NGAL (Neutrophil Gelatinase-associated Lipocalin ) is a protein of lipocalin superfamily. Recent literature focused on its biomarkers function in several pathological condition (acute and chronic kidney damage, autoimmune disease, malignancy). NGAL biological role is not well elucidated. Several are the demonstration of its bacteriostatic role. Recent papers have indeed highlight NGAL role in NFkB modulation. The aim of this study is to understand whether NGAL may exert a role in the activation (modulation) of T cell response through the regulation of HLA-G complex, a mediator of tolerance. From 8 healthy donors we obtained peripheral blood mononuclear cells (PBMCs) and we isolated by centrifugation on a Ficoll gradient. Cells were then treated with four concentrations of NGAL (40-320 ng/ml) with or without iron. We performed flow cytometry analysis and ELISA test. NGAL increased the HLA-G expression on CD4+ T cells, with an increasing corresponding to the dose. Iron effect is not of unique interpretation. NGAL adiction affects regulatory T cells increasing in vitro expansion of CD4+ CD25+ FoxP3+ cells. Neutralizing antibody against NGAL decreased HLA-G expression and reduced significantly CD4+ CD25+ FoxP3+ cells percentage. In conclusion, we provided in vitro evidence of NGAL involvement in cellular immunity. The potential role of NGAL as an immunomodulatory molecule has been evaluated: it has been shown that NGAL plays a pivotal role in the induction of immune tolerance up regulating HLA-G and T regulatory cells expression in healthy donors. As potential future scenario we highlight the in vivo role of NGAL in immunology and immunomodulation, and its possible relationship with immunosuppressive therapy efficacy, tolerance induction in transplant patients, and/or in other immunological disorders.

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In der vorliegenden Studie wurden verschiedene Techniken eingesetzt um drei Proben (4, 7, and 8) die aus denrnKorrosionsprodukten von aus dem Kosovo Krieg stammenden Munitionskugeln, bestehend aus abgereichertem Uranrn(Depleted Uranium - DU), zu untersuchen. Als erstes Verfahren wurde die Raman-Spektroskopie eingesetzt. Hierbeirnzeigte sichin den Proben, charakterisiert durch einen Doppelpeak, die Anwesenheit von Schoepitrn(UO2)8O2(OH)12(H2O)12. Der erste und zweite Peakzeigte sich im Spektralbereich von 840,3-842,5 cm-1rnbeziehungsweise 853,6-855,8 cm-1. Diese Werte stimmen mit den Literaturwerten für Raman-Peaks für Schoepitrnüberein. Des Weiteren wurde bei dieser Untersuchungsmethode Becquerelite Ca(UO2)6O4(OH)6(H2O)8 mit einemrnPeak im Bereich zwischen 829 to 836 cm-1 gefunden. Aufgrund des Fehlens des Becquerelitespektrums in derrnSpektralbibliothek wurde eine in der Natur vorkommende Variante analysiert und deren Peak bei 829 cm-1 bestimmt,rnwas mit den Ergebnissen in den Proben korrespondiert. Mittels Röntgenbeugung (X-Ray Diffraction, XRD) zeigtenrnsich in allen Proben ähnliche Spektren. Das lässt darauf schließen, dass das pulverisierte Material in allen Probenrndas gleiche ist. Hierbei zeigte sich eine sehr gute Übereinstimmung mit Schoepit und/oder meta-rnSchoepit(UO2)8O2(OH)12(H2O)10, sowie Becquerelite. Weiterhin war weder Autunit, Sabugalit noch Uranylphosphatrnanwesend, was die Ergebnisse einer anderen Studie, durchgeführt an denselben Proben, wiederlegt. DiernAnwesenheit von P, C oder Ca im Probenmaterial konnte ausgeschlossen werden. Im Falle von Calciumkann diesrnmit der Anwesenheit von Uran erklärt werden, welches aufgrund seines Atomradius bevorzugt in Becquerelite (1:6)rneingebaut wird. Die beiden Hauptpeaks für Uran lagen im Falle von U 4f 7/2 bei 382.0 eV und im Falle von U 4f 5/2rnbei 392 eV. Diese Werte mit den Literaturwerten für Schoepit und meta-Schoepitüberein. Die Ergebnissernelektronenmikroskopischen Untersuchung zeigen U, O, Ca, Ti als dominante Komponenten in allen Messungen.rnElemente wie Si, Al, Fe, S, Na, und C wurden ebenfalls detektiert; allerdings kann nicht ausgeschlossen werden,rndass diese Elemente aus dem Boden in der unmittelbaren Umgebung der Munitionsgeschosse stammen. Gold wurdernebenfalls gemessen, was aber auf die Goldarmierung in den Probenaufbereitungsbehältern zurückgeführt werdenrnkann. Die Elektronenmikroskopie zeigte außerdem einige Stellen in denen elementares Uran und Bodenmineralernsowie sekundäre Uranminerale auftraten. Die Elementübersicht zeigt einen direkten Zusammenhang zwischen U andrnCa und gleichzeitig keine Korrelation zwischen U und Si, oder Mg. Auf der anderen Seite zeigte sich aber einrnZusammenhang zwischen Si und Al da beide Konstituenten von Bodenmineralen darstellen. Eine mit Hilfe derrnElektronenstrahlmikroanalyse durchgeführte quantitative Analyse zeigte den Massenanteil von Uran bei ca. 78 - 80%,rnwas mit den 78,2% and 79,47% für Becquerelite beziehungsweise Schoepit aufgrund ihrer Summenformelrnkorrespondiert. Zusätzlich zeigt sich für Calcium ein Massenanteil von 2% was mit dem Wert in Becquerelite (2.19%)rnrecht gut übereinstimmt. Der Massenanteil von Ti lag in einigen Fällen bei 0,77%, was auf eine noch nicht korrodierternDU-Legierung zurückzuführen ist. Ein Lösungsexperiment wurde weiterhin durchgeführt, wobei eine 0,01 M NaClO4-rnLösung zum Einsatz kam in der die verbliebene Probensubstanz der Korrosionsprodukte gelöst wurde;rnNatriumperchlorate wurde hierbei genutzt um die Ionenstärke bei 0,01 zu halten. Um Verunreinigungen durchrnatmosphärisches CO2 zu vermeiden wurden die im Versuch für die drei Hauptproben genutzten 15 Probenbehälterrnmit Stickstoffgas gespült. Eine Modelkalkulation für den beschriebenen Versuchsaufbau wurde mit Visual MINTEQrnv.3.0 für die mittels vorgenannten Analysemethoden beschriebenen Mineralphasen im pH-Bereich von 6 – 10 imrnFalle von Becquerelite, und Schoepit berechnet. Die modellierten Lösungskurven wurden unter An- und Abwesenheitrnvon atmosphärischem CO2 kalkuliert. Nach dem Ende des Lösungsexperiments (Dauer ca. 6 Monate) zeigten diernKonzentrationen des gelösten Urans, gemessen mittels ICP-OES, gute Übereinstimmung mit den modelliertenrnSchoepit und Becquerelite Kurven. Auf Grund des ähnlichen Löslichkeitverhaltens war es nicht möglich zwichen denrnbeiden Mineralen zu unterscheiden. Schoepit kontrolliert im sauren Bereich die Löslichkeit des Urans, währendrnbecquerelit im basichen am wenigsten gelöst wird. Des Weiteren bleibt festzuhalten, dass ein Anteil an CO2 in diernverschlossenen Probenbehälter eingedrungen ist, was sich mit der Vorhersage der Modeldaten deckt. Die Löslichkeitrnvon Uran in der Lösung als Funktion des pH-Wertes zeigte die niedrigsten Konzentrationen im Falle einer Zunahmerndes pH-Wertes von 5 auf 7 (ungefähr 5,1 x 10-6 mol/l) und einer Zunahme des pH-Wertes auf 8 (ungefähr 1,5 x 10-6rnmol/l bei). Oberhalb dieses Bereichs resultiert jeder weitere Anstieg des pH-Wertes in einer Zunahme gelösten Uransrnin der Lösung. Der ph-Wert der Lösung wie auch deren pCO2-Wert kontrollieren hier die Menge des gelösten Urans.rnAuf der anderen Seite zeigten im Falle von Becquerelite die Ca-Konzentrationen höhere Werte als erwartet, wobeirnwahrscheinlich auf eine Vermischung der Proben mit Bodensubstanz zurückgeführt werden kann. Abschließendrnwurde, unter Berücksichtigung der oben genannten Ergebnisse, eine Fallstudie aus Basrah (Irak) diskutiert, wo inrnzwei militärischen Konflikten Uranmunition in zwei Regionen unter verschiedenen Umweltbedingungen eingesetztrnwurden.

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Biomass transformation into high-value chemicals has attracted attention according to the “green chemistry” principles. Low price and high availability make biomass one of the most interesting renewable resources as it provides the means to create sustainable alternatives to the oil-derived building blocks of the chemical industry In recent year, the need for alternative environmentally friendly routes to drive chemical reactions has in photocatalytic processes an interesting way to obtain valuable chemicals from various sources using the solar light as energy source. The purpose of this work was to use supported noble metal nanoparticles in the selective photo-oxidation of glucose through using visible light. Glucose was chosen as model molecule because it is the cheapest and the most common monosaccharide. Few studies about glucose photo oxidation have been conducted so far, and reaction mechanism is still not totally explained. The aim of this work was to systematically analyze and assess the impact of several parameters (eg. catalyst/substrate ratio, reaction time, effect of the solvent and light source) on the reaction pathway and to monitor the product distribution in order to draw a general reaction scheme for the photo oxidation of glucose under visible light. This study regards the reaction mechanism and the influence of several parameters, such as solvent, light power and substrate concentration. Furthermore, the work focuses on the influence of gold and silver nanoparticles and on the influence of metal loading. The glucose oxidation was monitored through the mass balance and the products selectivity. Reactions were evaluated in terms of glucose conversion, mass balance and selectivities towards arabinose and gluconic acid. In conclusion, this study is able to demonstrate that the photo oxidation of glucose under visible light is feasible; the full identification of the main products allows, for the first time, a comprehensive reaction mechanism scheme.

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Background The goal when resuscitating trauma patients is to achieve adequate tissue perfusion. One parameter of tissue perfusion is tissue oxygen saturation (StO2), as measured by near infrared spectroscopy. Using a commercially available device, we investigated whether clinically relevant blood loss of 500 ml in healthy volunteers can be detected by changes in StO2 after a standardized ischemic event. Methods We performed occlusion of the brachial artery for 3 minutes in 20 healthy female blood donors before and after blood donation. StO2 and total oxygenated tissue hemoglobin (O2Hb) were measured continuously at the thenar eminence. 10 healthy volunteers were assessed in the same way, to examine whether repeated vascular occlusion without blood donation exhibits time dependent effects. Results Blood donation caused a substantial decrease in systolic blood pressure, but did not affect resting StO2 and O2Hb values. No changes were measured in the blood donor group in the reaction to the vascular occlusion test, but in the control group there was an increase in the O2Hb rate of recovery during the reperfusion phase. Conclusion StO2 measured at the thenar eminence seems to be insensitive to blood loss of 500 ml in this setting. Probably blood loss greater than this might lead to detectable changes guiding the treating physician. The exact cut off for detectable changes and the time effect on repeated vascular occlusion tests should be explored further. Until now no such data exist.

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OBJECTIVES: Smoking is the most prevalent modifiable risk factor for cardiovascular diseases among HIV-positive persons. We assessed the effect on smoking cessation of training HIV care physicians in counselling. METHODS: The Swiss HIV Cohort Study (SHCS) is a multicentre prospective observational database. Our single-centre intervention at the Zurich centre included a half day of standardized training for physicians in counselling and in the pharmacotherapy of smokers, and a physicians' checklist for semi-annual documentation of their counselling. Smoking status was then compared between participants at the Zurich centre and other institutions. We used marginal logistic regression models with exchangeable correlation structure and robust standard errors to estimate the odds of smoking cessation and relapse. RESULTS: Between April 2000 and December 2010, 11 056 SHCS participants had 121 238 semi-annual visits and 64 118 person-years of follow-up. The prevalence of smoking decreased from 60 to 43%. During the intervention at the Zurich centre from November 2007 to December 2009, 1689 participants in this centre had 6068 cohort visits. These participants were more likely to stop smoking [odds ratio (OR) 1.23; 95% confidence interval (CI) 1.07-1.42; P = 0.004] and had fewer relapses (OR 0.75; 95% CI 0.61-0.92; P = 0.007) than participants at other SHCS institutions. The effect of the intervention was stronger than the calendar time effect (OR 1.19 vs. 1.04 per year, respectively). Middle-aged participants, injecting drug users, and participants with psychiatric problems or with higher alcohol consumption were less likely to stop smoking, whereas persons with a prior cardiovascular event were more likely to stop smoking. CONCLUSIONS: An institution-wide training programme for HIV care physicians in smoking cessation counselling led to increased smoking cessation and fewer relapses.

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BACKGROUND: The Roche CARDIAC proBNP point-of-care (POC) test is the first test intended for the quantitative determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) in whole blood as an aid in the diagnosis of suspected congestive heart failure, in the monitoring of patients with compensated left-ventricular dysfunction and in the risk stratification of patients with acute coronary syndromes. METHODS: A multicentre evaluation was carried out to assess the analytical performance of the POC NT-proBNP test at seven different sites. RESULTS: The majority of all coefficients of variation (CVs) obtained for within-series imprecision using native blood samples was below 10% for both 52 samples measured ten times and for 674 samples measured in duplicate. Using quality control material, the majority of CV values for day-to-day imprecision were below 14% for the low control level and below 13% for the high control level. In method comparisons for four lots of the POC NT-proBNP test with the laboratory reference method (Elecsys proBNP), the slope ranged from 0.93 to 1.10 and the intercept ranged from 1.8 to 6.9. The bias found between venous and arterial blood with the POC NT-proBNP method was < or =5%. All four lots of the POC NT-proBNP test investigated showed excellent agreement, with mean differences of between -5% and +4%. No significant interference was observed with lipaemic blood (triglyceride concentrations up to 6.3 mmol/L), icteric blood (bilirubin concentrations up to 582 micromol/L), haemolytic blood (haemoglobin concentrations up to 62 mg/L), biotin (up to 10 mg/L), rheumatoid factor (up to 42 IU/mL), or with 50 out of 52 standard or cardiological drugs in therapeutic concentrations. With bisoprolol and BNP, somewhat higher bias in the low NT-proBNP concentration range (<175 ng/L) was found. Haematocrit values between 28% and 58% had no influence on the test result. Interference may be caused by human anti-mouse antibodies (HAMA) types 1 and 2. No significant influence on the results with POC NT-proBNP was found using volumes of 140-165 muL. High NT-proBNP concentrations above the measuring range of the POC NT-proBNP test did not lead to false low results due to a potential high-dose hook effect. CONCLUSIONS: The POC NT-proBNP test showed good analytical performance and excellent agreement with the laboratory method. The POC NT-proBNP assay is therefore suitable in the POC setting.

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CONTEXT: A polymorphism of the GH receptor (GHR) gene resulting in genomic deletion of exon 3 (GHR-d3) has been associated with responsiveness to GH therapy. However, the data reported so far do vary according to the underlying condition, replacement dose, and duration of the treatment. OBJECTIVE, DESIGN: The aim of this study was to analyze the impact of the GHR genotypes in terms of the initial height velocity (HV) resulting from treatment and the impact upon adult height in patients suffering from severe isolated GH deficiency. CONTROLS, PATIENTS, SETTING: A total of 181 subjects (peak stimulated GHeffect of recombinant human GH dose used, and final height were analyzed. MAIN OUTCOME MEASURES, RESULTS: In the 181 subjects after the first two yr on recombinant human GH treatment, HV sd score (SDS) as well as height gain were significantly greater in subjects with the GHR-d3/d3 genotype when compared with the subjects presenting with the GHR-full-length/full-length genotype (P<0.05). A GHR-d3 allele dose-dependent effect was found for both HV SDS (r=0.72) and height gain (r=0.77). However, there was no significant difference in final adult height and height SDS according to the exon-3 genotypes. CONCLUSIONS: Our results indicate that in patients with severe isolated GH deficiency, although the GHR genotype might play a role in GH responsiveness, at least at the beginning of treatment, there is no effect on final height.

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In the literature on migration, as well as in social policies regarding this phenomenon, the situation of returning emigrants receives scant attention. This essay establishes an intricate connection between attitudes and policies that prevail in a country regarding emigration and those concerning immigration. The case of Italy provides a prime example for this as it once was a classical country of emigration, only to turn, in recent decades, into a country that appears highly attractive (and relatively accessible) to immigrants. The essay traces the pervasive ambiguity that characterizes this country’s attitudes towards emigration from the beginning of mass emigration shortly after the unification of Italy in 1868 to the emigration policies of the fascist regime of Mussolini and the post-World War II waves of emigration right through to the corresponding ambiguity concerning the status of immigrants in contemporary society, including the indifferent treatment of returning Italian emigrants who constitute a considerable numerical phenomenon. These reflections take their origin from the impending closure of a reception centre in Lazio, the Casa dell’Emigrante near Sant’Elia Fiumerapido, Province of Frosinone, ostensibly for financial reasons. This centre had been the only one of its kind in the whole of Italy dealing officially with the needs of repatriated Italians. It had assisted returning emigrants both with practical matters, such as negotiating the labyrinth of Italian bureaucracy , and with psychological implications of a return, which are often considerable given the time lag of experiences with current social realities and the frequently unrealistic expectations associated with the return. Questions of identity become highly acute in those circumstances. The threatened closure of the centre illustrates the unwillingness of the state to face up to the factual prevalence of migratory experiences in the country as a whole and as a core element of national history, experiences of migration in both directions. The statistics speak for themselves: of the 4.660.427 persons who left Italy between 1880 and 1950, 2.322.451 have returned, almost exactly 50%. To those have to be added 3.628.430 returnees of the 5.109.860 emigrants who left Italy between the end of World War II and 1976 for Europe alone. Attitudes towards people leaving changed ostensibly over time. In the first two decades after Unification parliament on the one hand wanted to show some concern over the fate of its citizens, not wanting to abandon those newly created citizens entirely to their own destiny, while on the other portraying their decisions to emigrate as expressions of individual liberty and responsibility and not necessitated by want and poverty. Emigrants had to prove, paradoxically that they had the requisite means to emigrate when in fact poverty was largely driving them to emigrate. To admit that publicly would have amounted to admission of economic and political failure made evident through emigration. In contrast to that Mussolini’s emigration policies not only enforced large population movements within the territory of Italy to balance unemployment between regions and particularly between North and South, but also declared it citizen’s duty to be ready to move also to the colonies, thereby ‘turning emigration as a sign of social crisis into a sign of national strength and the success of the country’s political agenda’ (Gaspari 2001, p. 34). The duplicity continued even after World War II when secret deals were done with the USA to allow a continuous flow of Italian immigrants and EU membership obviously further facilitated the departure of unemployed, impoverished Italians. With the growing prosperity of Italy the reversal of the direction of migration became more obvious. On the basis of empirical research conducted by one of the author on returning emigrants four types of motives for returning can be distinguished: 1. Return as a result of failure – particularly the emigrants who left during the 1950-1970 period usually had no linguistic preparation, and in any case the gap between the spoken and the written language is enormous with the latter often being insurmountable. This gives rise to nostalgic sentiments which motivates a return into an environment where language is familiar 2. Return as a means of preserving an identity – the life of emigrants often takes place within ghetto-like conditions where familiarity is being reproduced but under restricted conditions and hence not entirely authentic. The necessity for saving money permits only a partial entry into the host society and at the same time any accumulating savings add to the desire to return home where life can be lived fully again – or so it seems. 3. Return of investment – the impossibility to become fully part of another society often motivates migrants to accumulate not so much material wealth but new experiences and competences which they then aim to reinvest in their home country. 4. Return to retire – for many emigrants returning home becomes acute once they leave a productive occupation and feelings of estrangement build up, in conjunction with the efforts of having invested in building a house back home. All those motives are associated with a variety of difficulties on the actual return home because, above all, time in relation to the country of origin has been suspended for the emigrant and the encounter with the reality of that country reveals constant discrepancies and requires constant readjustment. This is where the need for assistance to returning emigrants arises. The fact that such an important centre of assistance has been closed is further confirmation of the still prevailing politics of ambiguity which nominally demand integration from nationals and non-nationals alike but deny the means of achieving this. Citizenship is not a natural result of nationality but requires the means for active participation in society. Furthermore, the experiences of returning immigrants provide important cues for the double ambivalence in which immigrants to Italy live between the demands made on them to integrate, the simultaneous threats of repatriation and the alienation from the immigrants’ home country which grows inexorably during the absence. The state can only regain its credibility by putting an end to this ambiguity and provide to returning emigrants, and immigrants alike, the means of reconstructing strong communal identities.

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Haldane (1935) developed a method for estimating the male-to-female ratio of mutation rate ($\alpha$) by using sex-linked recessive genetic disease, but in six different studies using hemophilia A data the estimates of $\alpha$ varied from 1.2 to 29.3. Direct genomic sequencing is a better approach, but it is laborious and not readily applicable to non-human organisms. To study the sex ratios of mutation rate in various mammals, I used an indirect method proposed by Miyata et al. (1987). This method takes advantage of the fact that different chromosomes segregate differently between males and females, and uses the ratios of mutation rate in sequences on different chromosomes to estimate the male-to-female ratio of mutation rate. I sequenced the last intron of ZFX and ZFY genes in 6 species of primates and 2 species of rodents; I also sequenced the partial genomic sequence of the Ube1x and Ube1y genes of mice and rats. The purposes of my study in addition to estimation of $\alpha$'s in different mammalian species, are to test the hypothesis that most mutations are replication dependent and to examine the generation-time effect on $\alpha$. The $\alpha$ value estimated from the ZFX and ZFY introns of the six primate specise is ${\sim}$6. This estimate is the same as an earlier estimate using only 4 species of primates, but the 95% confidence interval has been reduced from (2, 84) to (2, 33). The estimate of $\alpha$ in the rodents obtained from Zfx and Zfy introns is ${\sim}$1.9, and that deriving from Ube1x and Ube1y introns is ${\sim}$2. Both estimates have a 95% confidence interval from 1 to 3. These two estimates are very close to each other, but are only one-third of that of the primates, suggesting a generation-time effect on $\alpha$. An $\alpha$ of 6 in primates and 2 in rodents are close to the estimates of the male-to-female ratio of the number of germ-cell divisions per generation in humans and mice, which are 6 and 2, respectively, assuming the generation time in humans is 20 years and that in mice is 5 months. These findings suggest that errors during germ-cell DNA replication are the primary source of mutation and that $\alpha$ decreases with decreasing length of generation time. ^

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Background: A relationship between bulimia nervosa (BN) and reward-related behavior is supported by several lines of evidence. The dopaminergic dysfunctions in the processing of reward-related stimuli have been shown to be modulated by the neurotrophin brain derived neurotrophic factor (BDNF) and the hormone leptin. Methods: Using a randomized, double-blind, placebo-controlled, crossover design, a reward learning task was applied to study the behavior of 20 female subjects with remitted BN (rBN) and 27 female healthy controls under placebo and catecholamine depletion with alpha-methyl-para-tyrosine (AMPT). The plasma levels of BDNF and leptin were measured twice during the placebo and the AMPT condition, immediately before and 1 h after a standardized breakfast. Results: AMPT-induced differences in plasma BDNF levels were positively correlated with the AMPT-induced differences in reward learning in the whole sample (p = 0.05). Across conditions, plasma BDNF levels were higher in rBN subjects compared to controls (diagnosis effect; p = 0.001). Plasma BDNF and leptin levels were higher in the morning before compared to after a standardized breakfast across groups and conditions (time effect; p < 0.0001). The plasma leptin levels were higher under catecholamine depletion compared to placebo in the whole sample (treatment effect; p = 0.0004). Conclusions: This study reports on preliminary findings that suggest a catecholamine-dependent association of plasma BDNF and reward learning in subjects with rBN and controls. A role of leptin in reward learning is not supported by this study. However, leptin levels were sensitive to a depletion of catecholamine stores in both rBN and controls.

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AIMS: To determine the efficacy of motivational enhancement therapy (MET) on alcohol use in patients with the hepatitis C virus (HCV) and an alcohol use disorder (AUD). DESIGN: Randomized, single-blind, controlled trial comparing MET to a control education condition with 6-month follow-up. SETTING: Patients were recruited from hepatitis clinics at the Minneapolis, Minnesota and Portland, Oregon Veterans Affairs Health Care Systems, USA. PARTICIPANTS AND INTERVENTION: Patients with HCV, an AUD and continued alcohol use (n = 139) were randomized to receive either MET (n = 70) or a control education condition (n = 69) over 3 months. MEASUREMENTS: Data were self-reported percentage of days abstinent from alcohol and number of standard alcohol drinks per week 6 months after randomization. FINDINGS: At baseline, subjects in MET had 34.98% days abstinent, which increased to 73.15% at 6 months compared to 34.63 and 59.49% for the control condition. Multi-level models examined changes in alcohol consumption between MET and control groups. Results showed a significant increase in percentage of days abstinent overall (F(1120.4)  = 28.04, P < 0.001) and a significant group × time effect (F(1119.9)  = 5.23, P = 0.024) with the MET group showing a greater increase in percentage of days abstinent at 6 months compared with the education control condition. There were no significant differences between groups for drinks per week. The effect size of the MET intervention was moderate (0.45) for percentage of days abstinent. CONCLUSION: Motivational enhancement therapy (MET) appears to increase the percentage of days abstinent in patients with chronic hepatitis C, alcohol use disorders and ongoing alcohol use. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

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PURPOSE Few studies have used multivariate models to quantify the effect of multiple previous spine surgeries on patient-oriented outcome after spine surgery. This study sought to quantify the effect of prior spine surgery on 12-month postoperative outcomes in patients undergoing surgery for different degenerative disorders of the lumbar spine. METHODS The study included 4940 patients with lumbar degenerative disease documented in the Spine Tango Registry of EUROSPINE, the Spine Society of Europe, from 2004 to 2015. Preoperatively and 12 months postoperatively, patients completed the multidimensional Core Outcome Measures Index (COMI; 0-10 scale). Patients' medical history and surgical details were recorded using the Spine Tango Surgery 2006 and 2011 forms. Multiple linear regression models were used to investigate the relationship between the number of previous surgeries and the 12-month postoperative COMI score, controlling for the baseline COMI score and other potential confounders. RESULTS In the adjusted model including all cases, the 12-month COMI score showed a 0.37-point worse value [95 % confidence intervals (95 % CI) 0.29-0.45; p < 0.001] for each additional prior spine surgery. In the subgroup of patients with lumbar disc herniation, the corresponding effect was 0.52 points (95 % CI 0.27-0.77; p < 0.001) and in lumbar degenerative spondylolisthesis, 0.40 points (95 % CI 0.17-0.64; p = 0.001). CONCLUSIONS We were able to demonstrate a clear "dose-response" effect for previous surgery: the greater the number of prior spine surgeries, the systematically worse the outcome at 12 months' follow-up. The results of this study can be used when considering or consenting a patient for further surgery, to better inform the patient of the likely outcome and to set realistic expectations.