821 resultados para Oviposition capacity


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In the last years, dendritic cells (DC) have been evaluated for antitumor vaccination. Although DC-based vaccines have raised great expectations, their clinical translation has been largely disappointing. For these results, several explanations have been proposed. In particular, the concomitant expression by DCs of tolerogenic pathways, such as the immunosuppressive agent indoleamine 2,3-dioxygenase-1 (IDO1), has been demonstrated. The aim of this study is to evaluate both the stimulatory and the tolerogenic feature of monocyte-derived DCs (Mo-DCs) after maturation with PGE2. In particular, the role of IDO1 expression in PGE2-matured Mo-DCs has been addressed. Here we show that PGE2, which is required for full maturation of DCs, is one mediator of DC tolerance by enhancing IDO1. PGE2-mediated expression of IDO1 results in the production of kynurenine, in the generation of Tregs, and in the inhibition of either the allogeneic or the autologous antigen-specific stimulatory capacity of DCs. When pulsed with leukemic lysates and matured with PGE2, DCs are impaired in the induction of IFN-γ secreting CD4(+) and CD8(+) T cells due to IDO1 upregulation. Moreover, the inhibition of IDO1 enhances the antileukemic response. Overall, these results point toward the use of IDO1 inhibitors to enhance the vaccination capacity of DCs, matured with PGE2.

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"Vegeu el resum a l'inici del document del fitxer adjunt."

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Traffic forecasts provide essential input for the appraisal of transport investment projects. However, according to recent empirical evidence, long-term predictions are subject to high levels of uncertainty. This paper quantifies uncertainty in traffic forecasts for the tolled motorway network in Spain. Uncertainty is quantified in the form of a confidence interval for the traffic forecast that includes both model uncertainty and input uncertainty. We apply a stochastic simulation process based on bootstrapping techniques. Furthermore, the paper proposes a new methodology to account for capacity constraints in long-term traffic forecasts. Specifically, we suggest a dynamic model in which the speed of adjustment is related to the ratio between the actual traffic flow and the maximum capacity of the motorway. This methodology is applied to a specific public policy that consists of suppressing the toll on a certain motorway section before the concession expires.

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Dispersal of five species of phlebotomine sand flies was studied in a coffee plantation near Arboledas, Colombia by mark-release-recapture studies using fluorescent powders. The estimated recapture rate for males of Lutzomyia shannoni marked and released during the day was 28.1% significantly higher than that for all other species (p < 0.05). Recapture rate of female Lu. shannoni was 9.5% and no females of the other four species were recovered. This suggests either that Lu. shannoni is a more sedentary species than the others, or that the large trees on wich these insects were captured and recaptured function as foci of lekking behaviour in males. The high recapture rates of females of this species may indicate that oviposition occurs in close proximity to the bases of these trees. Although most marked sand flies were recaptured within 200 m of their release point, a single female Lu. gomezi was recovered 960 m away 36 h after release. This suggests that the dispersal capacity of Lutzomyia species may be greater than has been though, an important consideration in future control programs directed against these insects in Leishmania-endemic areas.

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Reproductive performance including mating, semen transfer, egg production and hatching rate were investigated in pairs of Panstrongylus megistus in wich the male was treated with either precocene II or ethoxyprecocene II, topically applied shortly after imaginal molt. Eighty percent of the males were not able to mate for a period as long as 40 days after treatment. Those males wich did mate (20%) produced small spermatophores; a few (10%) were unable to transfer spermatozoa to female, while the others (10%) exhibited reproductive performance similar to that of non-treated males. The cumulative effects of the precocene on the different stages of reproduction resulted in a drastic reduction of offspring production. The anti-allatal compound precocene seems to inhibit successful reproduction through a corpus allatum inactivation and subsequent lack of secretory activity of the male accessory glands.

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Introduction: Low back pain is a common disorder touching up to 80% of the population, with redundancies of up to 70%. A small proportion would go on to develop chronic low back pain (LBP) with reduced work capacity and they would count for the majority of the costs. Up to day, a multi-disciplinary treatment program is one of the best approaches. In the program one of the mile-stones is restoration of function. The aim of this study was to follow patients, according to the endurance change after the program and its influence on workability during one year after inclusion in a such program. Method: Patients were following a multidisciplinary treatment for 3 weeks including physiotherapy, occupation measures combined with an educational program with behavioural and psychological interventions on an outpatient program. We studied the endurance with the help of the Bruce test, accomplished at the beginning and at the end of the program. On the other hand the patients filled out pain questionnaires and PACT score according their own impression on workability. Results: There were a clear relation between the increase in the cardiovascular endurance and the increased workability. Almost every patient presented an increase in the VO2 max, even though the workability did not follow. This increase were associated with a decrease in pain apprehension. Conclusion: A multidisciplinary treatment program, teaching the patients how to care with their pain and to accept it even if it persist is successful in lowering the global pain. If the program allows the patients to strengthen the endurance, the workability will increase in parallel. In this way the patients were able to reduce the consummation of medicaments and to increase the work capacity.

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The effects of radiation on the reproductive capacity and the longevity of Panstrongylus magistus were studied. An indirect correlation between longevity and radiation doses was observed. Males were more affected than females. Longevity of females submitted to 10 Gy was not different when compared to controls. Some of the irradiated males copulated and in these cases semen was transferred to females, but only few eggs were laid. Fertility was seriously affected in all irradiated groups, decreasing with increasing intensity of dose. The dose of 80 Gy induced sterility in males and females. Gelatinous spermatophores that were expelled by females irradiated with 20 and 40 Gy, may be a consequence of irradiation that induced modification in the bursa copulatrix pH.

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Schneider's Drosophila medium, a complex amino acid rich medium was tested alone and with seven different sugars for some aspects of the biology of Lutzomyia longipalpis. Statistically significant results were obtained when sucrose was used alone, indicating that among the sugars tested, this is still the most suitable and practical one for the maintenance of L. longipalpis colonies. However, the addition of Schneider's medium to a pool of different sugars, was suggested to be related with the acceptance of the first and second blood meals and to longevity, these being, obviously, quite relevant aspects when tansmission experiments are contemplated.

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Objective: It was the aim of this study to investigate facial emotion recognition (FER) in the elderly with cognitive impairment. Method: Twelve patients with Alzheimer's disease (AD) and 12 healthy control subjects were asked to name dynamic or static pictures of basic facial emotions using the Multimodal Emotion Recognition Test and to assess the degree of their difficulty in the recognition task, while their electrodermal conductance was registered as an unconscious processing measure. Results: AD patients had lower objective recognition performances for disgust and fear, but only disgust was accompanied by decreased subjective FER in AD patients. The electrodermal response was similar in all groups. No significant effect of dynamic versus static emotion presentation on FER was found. Conclusion: Selective impairment in recognizing facial expressions of disgust and fear may indicate a nonlinear decline in FER capacity with increasing cognitive impairment and result from progressive though specific damage to neural structures engaged in emotional processing and facial emotion identification. Although our results suggest unchanged unconscious FER processing with increasing cognitive impairment, further investigations on unconscious FER and self-awareness of FER capacity in neurodegenerative disorders are required.

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To determine the influence of physical factors on oviposition of Lutzomyia migonei (Diptera: Psychodidae) under laboratory conditions, two sets of experiments were performed. The first test was to determine the influence of the size of pots on oviposition. Gravid flies were placed individually or in groups in different oviposition pots. The number of eggs laid, oviposition time and survival of gravid females were observed. In the second experiment, the influence of irregular surfaces on oviposition was studied. The results suggested that physical space was not an important factor in the oviposition behavior of L. migonei and that the flies showed a preference to oviposit on irregular horizontal surfaces in response to thigmotropic behavior

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Protection against reinfection is mediated by Ag-specific memory CD8 T cells, which display stem cell-like function. Because canonical Wnt (Wingless/Int1) signals critically regulate renewal versus differentiation of adult stem cells, we evaluated Wnt signal transduction in CD8 T cells during an immune response to acute infection with lymphocytic choriomeningitis virus. Whereas naive CD8 T cells efficiently transduced Wnt signals, at the peak of the primary response to infection only a fraction of effector T cells retained signal transduction and the majority displayed strongly reduced Wnt activity. Reduced Wnt signaling was in part due to the downregulation of Tcf-1, one of the nuclear effectors of the pathway, and coincided with progress toward terminal differentiation. However, the correlation between low and high Wnt levels with short-lived and memory precursor effector cells, respectively, was incomplete. Adoptive transfer studies showed that low and high Wnt signaling did not influence cell survival but that Wnt high effectors yielded memory cells with enhanced proliferative potential and stronger protective capacity. Likewise, following adoptive transfer and rechallenge, memory cells with high Wnt levels displayed increased recall expansion, compared with memory cells with low Wnt signaling, which were preferentially effector-like memory cells, including tissue-resident memory cells. Thus, canonical Wnt signaling identifies CD8 T cells with enhanced proliferative potential in part independent of commonly used cell surface markers to discriminate effector and memory T cell subpopulations. Interventions that maintain Wnt signaling may thus improve the formation of functional CD8 T cell memory during vaccination.

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Introduction. Respiratory difficulties in athletes are common, especially in adolescents, even in the absence of exercise-induced bronchoconstriction. Immaturity of the respiratory muscles coupling at high respiratory rates could be a potential mechanism. Whether respiratory muscle training (RMT) can positively influence it is yet unknown. Goal. We investigate the effects of RMT on ventilation and performance parameters in adolescent athletes and hypothesize that RMT will enhance respiratory capacity. Methods. 12 healthy subjects (8 male, 4 female, 17±0.5 years) from a sports/study high school class, competitively involved in various sports (minimum of 10 hours per week) underwent respiratory function testing, maximal minute ventilation (MMV) measurements and a maximal treadmill incremental test with VO2max and ventilatory thresholds (VT1 and VT2) determination. They then underwent one month of RMT (4 times/week) using a eucapnic hyperventilation device, with an incremental training program. The same tests were repeated after RMT. Results. Subjects completed 14.8 sessions of RMT, with an increase in total ventilation per session of 211±29% during training. Borg scale evaluation of the RMT session was unchanged or reduced in all subjects, despite an increase in total respiratory work. No changes (p>0.05) were observed pre/post RMT in VO2max (53.4±7.5 vs 51.6±7.7 ml/kg/min), VT2 (14.4±1.4 vs 14.0±1.1 km/h) or Speed max at end of test (16.1±1.7 vs 15.8±1.7 km/h). MVV increased by 9.2% (176.7±36.9 vs 192.9±32.6 l/min, p<0.001) and FVC by 3.3% (6.70±0.75 vs 4.85±0.76 litres, p<0.05). Subjective evaluation of respiratory sensations during exercise and daily living were also improved. Conclusions. RMT improves MMV and FVC in adolescent athletes, along with important subjective respiratory benefits, although no changes are seen in treadmill maximal performance tests and VO2max measurements. RMT can be easily performed in adolescent without side effects, with a potential for improvement in training capacity and overall well-being.

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This paper analyses whether a firm’s absorptive capacity and its distance from the technological frontier affect the choice between innovation and imitation in innovative Spanish firms. From an extensive survey of 5,575 firms during the 2004-2009 period, we found two significant results. With regard to the role of absorptive capacity, the empirical evidence shows that when innovative firms have difficulties in accessing external information and hire skilled workers, their innovative capacity is reduced. Meanwhile, with regard to distance from the technological frontier, the firms that reduce this gap manage to increase their innovative capacity at the expense of imitation. To summarise, when we studied firms’ absorptive capacity and their relative position to the technological frontier in tandem, we found that the two factors directly affected firms' ability to innovate or imitate.