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1.
Sci Total Environ ; 838(Pt 4): 156592, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35690195

RESUMO

The intense rainfall associated with the Intertropical Convergence Zone (ITCZ), a narrow zone of confluence of the northeast and southeast trades, can significantly alter sea surface salinity, the chemistry of inorganic C and the resulting sea-air CO2 exchange in the tropics. We have analyzed extensive underway data collected from 2008 until 2014 and recorded by an autonomous CO2 system installed on a commercial ship that crosses the central tropical Atlantic (5°S to 15°N, 18°W to 36°W) to disentangle the effects of the ITCZ over the carbonate system there. Based on statistically significant linear co-variance of sea surface fugacity of CO2 (fCO2sw) and sea surface salinity in the areas affected by the ITCZ, we calculated CO2 drawdown rates associated with the impact of the ITCZ in the central tropical Atlantic ranging from 0.11 ± 0.02 to 2.35 ± 0.08 mmol m-2 d-1. These were calculated by comparing the observed fCO2sw with that expected without surface seawater carbonate system dilution and increase in gas transfer caused by the ITCZ. The observed decrease in fCO2sw associated with the freshening caused by the ITCZ is much larger than expected from thermodynamics alone. 59.1 ± 4.1 % of the total observed CO2 drawdown associated with the ITCZ cannot be explained by abiotic processes. Instead, we found significant negative correlations between underway sea surface salinity and remote-sensed chlorophyll a in the areas affected by the ITCZ. Different to other tropical oceanic basins, the tropical Atlantic receives large amounts of continental dust originated from Africa. Wet dust deposition driven by the ITCZ appears associated with the interannual variability of the CO2 drawdown associated with the ITCZ. Fertilization driven by the ITCZ seems to enhance primary production in the otherwise oligotrophic tropical Atlantic, thus significantly lowering CO2 emissions to the atmosphere.


Assuntos
Atmosfera , Dióxido de Carbono , Clorofila A , Poeira , Água do Mar
2.
Int Arch Occup Environ Health ; 94(6): 1271-1285, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33686473

RESUMO

PURPOSE: To identify the factors affecting teachers' vocal acoustic parameters, with the aim of detecting individuals at risk of phonotrauma. METHOD: The voicing time, voice sound pressure level [SPL] and fundamental frequency [fo] of 87 teachers were measured during one workweek using a voice dosimeter. We retrospectively investigated the impact of 10 factors (gender, age, teaching experience, teaching level, tobacco, gastro-esophageal problems, nonoccupational voice activity, voice education, past voice problems, and biopsychosocial impact of voice problems measured using the Voice Handicap Index [VHI]) on each voice parameter. RESULTS: None of the above factors affected voicing time or SPL. fo depended significantly on gender, teaching level, nonoccupational voice activity and VHI score. Specifically, fo was higher in women (Δ = 69 Hz), in individuals without nonoccupational voice activities (Δ = 11 Hz), and in individuals with a lower VHI score (increase of 0.7 Hz for each additional point). For females, post hoc comparisons revealed a substantial impact of teaching level on fo: university instructors had deeper voices than kindergarten (Δ = 66 Hz), elementary (Δ = 52 Hz), or secondary teachers (Δ = 41 Hz). CONCLUSIONS: Since higher fo increases the mechanical stress related to vocal fold vibration, the screening and prevention of phonotrauma should focus primarily on women, particularly those who teach at lower levels, and teachers with more self-rated voice problems. The lower fo of teachers who engage in nonprofessional voice activities may suggest acute inflammation or muscle fatigue due to voice overload.


Assuntos
Pessoal de Educação , Distúrbios da Voz/epidemiologia , Acústica , Adulto , Bélgica/epidemiologia , Monitoramento Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
3.
Mem Cognit ; 48(3): 361-369, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31529261

RESUMO

Spatial biases associated with subtraction or addition problem solving are generally considered as reflecting leftward or rightward attention shifts along a mental numerical continuum, but an alternative hypothesis not implying spatial attention proposes that the operator (plus or minus sign) may favour a response to one side of space (left or right) because of semantic associations. We tested these two accounts in a series of temporal order judgement experiments that consisted in the auditory presentation of addition or subtraction problems followed 200 ms (Experiments 1-2) or 800 ms (Experiment 3) later by the display of two lateralized targets in close temporal succession. To dissociate the side where the operation first brought their attention from the side they had to respond to, we asked participants to report which of the left or right target appeared first or last on screen. Under the attention-orienting account, addition should elicit more rightward responses than subtraction when participants have to focus on the first target, but more leftward responses when they have to focus on the last target, because the latter is opposite to the side where the operation first brought their attention. Under the semantic account, addition should elicit more rightward responses than subtraction, no matter the focus is on the first or last target, because participants should systematically favour the side conceptually linked to the operator. The results of the three experiments converge to indicate that, in lateralized target detection tasks, the spatial biases induced by arithmetic operations stem from semantic associations.


Assuntos
Associação , Percepção Auditiva/fisiologia , Julgamento/fisiologia , Conceitos Matemáticos , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Semântica , Adulto Jovem
4.
Sci Rep ; 9(1): 20153, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882779

RESUMO

Shelf seas play an important role in the global carbon cycle, absorbing atmospheric carbon dioxide (CO2) and exporting carbon (C) to the open ocean and sediments. The magnitude of these processes is poorly constrained, because observations are typically interpolated over multiple years. Here, we used 298500 observations of CO2 fugacity (fCO2) from a single year (2015), to estimate the net influx of atmospheric CO2 as 26.2 ± 4.7 Tg C yr-1 over the open NW European shelf. CO2 influx from the atmosphere was dominated by influx during winter as a consequence of high winds, despite a smaller, thermally-driven, air-sea fCO2 gradient compared to the larger, biologically-driven summer gradient. In order to understand this climate regulation service, we constructed a carbon-budget supplemented by data from the literature, where the NW European shelf is treated as a box with carbon entering and leaving the box. This budget showed that net C-burial was a small sink of 1.3 ± 3.1 Tg C yr-1, while CO2 efflux from estuaries to the atmosphere, removed the majority of river C-inputs. In contrast, the input from the Baltic Sea likely contributes to net export via the continental shelf pump and advection (34.4 ± 6.0 Tg C yr-1).

5.
Q J Exp Psychol (Hove) ; 71(10): 2142-2151, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30226431

RESUMO

Previous studies showed that the magnitude information conveyed by sensory cues, such as length or surface, influences the ability to compare the numerosity of sets of objects. However, the perceptual nature of this representation and how it interacts with the processes involved in numerical judgements remain unclear. This study aims to address these issues by studying the interference of length on numerosity under different perceptual and response conditions. The first experiment shows that the influence of length does not depend on the actual length but on subjective values reflecting the way length is perceived in a given visual context. The Müller-Lyer illusion was used to manipulate the perceived length of two dot arrays independently of their actual length. When the length of two dot arrays was equal but perceived as different due to the illusion, participants erroneously reported differences in the number of dots contained in each array, evidencing a similar effect of Müller-Lyer illusion on length and numerosity comparison. This finding was replicated in a second experiment where participants had to give a verbal estimate of the number of dots contained in a given array, thereby eliminating the choice between a small or large response. Compared with a neutral condition, estimations were systematically larger than the actual number of dots as the illusory length increased. These results demonstrate that the illusory-induced experience of length influences numerosity estimation over and beyond objective cues and that this influence is not a response selection bias.


Assuntos
Ilusões/fisiologia , Julgamento/fisiologia , Matemática , Reconhecimento Visual de Modelos/fisiologia , Percepção de Tamanho/fisiologia , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Estimulação Luminosa , Probabilidade , Adulto Jovem
6.
Front Microbiol ; 8: 1358, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824554

RESUMO

The Amazon generates the world's largest offshore river plume, which covers extensive areas of the tropical Atlantic. The data and samples in this study were obtained during the oceanographic cruise Camadas Finas III in October 2012 along the Amazon River-Ocean Continuum (AROC). The cruise occurred during boreal autumn, when the river plume reaches its maximum eastward extent. In this study, we examine the links between physics, biogeochemistry and plankton community structure along the AROC. Hydrographic results showed very different conditions, ranging from shallow well-mixed coastal waters to offshore areas, where low salinity Amazonian waters mix with open ocean waters. Nutrients, mainly [Formula: see text] and [Formula: see text], were highly depleted in coastal regions, and the magnitude of primary production was greater than that of respiration (negative apparent oxygen utilization). In terms of phytoplankton groups, diatoms dominated the region from the river mouth to the edge of the area affected by the North Brazil Current (NBC) retroflection (with chlorophyll a concentrations ranging from 0.02 to 0.94 mg m-3). The North Equatorial Counter Current (NECC) region, east of retroflection, is fully oligotrophic and the most representative groups are Cyanobacteria and dinoflagellates. Additionally, in this region, blooms of cyanophyte species were associated with diatoms and Mesozooplankton (copepods). A total of 178 zooplankton taxa were observed in this area, with Copepoda being the most diverse and abundant group. Two different zooplankton communities were identified: a low-diversity, high-abundance coastal community and a high-diversity, low-abundance oceanic community offshore. The CO2 fugacity (fCO2sw), calculated from total alkalinity (1,450 < TA < 2,394 µmol kg-1) and dissolved inorganic carbon (1,303 < DIC < 2,062 µmol kg-1) measurements, confirms that the Amazon River plume is a sink of atmospheric CO2 in areas with salinities <35 psu, whereas, in regions with salinities >35 and higher-intensity winds, the CO2 flux is reversed. Lower fCO2sw values were observed in the NECC area. The ΔfCO2 in this region was less than 5 µatm (-0.3 mmol m-2 d-1), while the ΔfCO2 in the coastal region was approximately 50 µatm (+3.7 mmol m-2 d-1). During the cruise, heterotrophic and autotrophic processes were observed and are indicative of the influences of terrestrial material and biological activity, respectively.

7.
Sci Rep ; 7: 41694, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134309

RESUMO

Following the 2009 Pacific El Niño, a warm event developed in the tropical and subtropical North Atlantic during boreal spring of 2010 promoted a significant increase in the CO2 fugacity of surface waters. This, together with the relaxation of the prevailing wind fields, resulted in the reversal of the atmospheric CO2 absorption capacity of the tropical and subtropical North Atlantic. In the region 0-30°N, 62-10°W, this climatic event led to the reversal of the climatological CO2 sink of -29.3 Tg C to a source of CO2 to the atmosphere of 1.6 Tg C from February to May. The highest impact of this event is verified in the region of the North Equatorial Current, where the climatological CO2 uptake of -22.4 Tg for that period ceased during 2010 (1.2 Tg C). This estimate is higher than current assessments of the multidecadal variability of the sea-air CO2 exchange for the entire North Atlantic (20 Tg year-1), and highlights the potential impact of the increasing occurrence of extreme climate events over the oceanic CO2 sink and atmospheric CO2 composition.

8.
Psychiatry Res ; 216(2): 242-7, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24564998

RESUMO

The role of stable factors, such as alexithymia (i.e., difficulties identifying and expressing feelings, externally oriented cognitive style), or temporary factors, such as affective states (mood), on emotion perception has been widely investigated in the literature. However, little is known about the separate or joint effect of the alexithymia level and affective states (positive affectivity, negative affectivity) on the recognition of nonverbal emotional vocalizations (NEV) (e.g., laughs, cries, or sighs). In this study, participants had to categorize NEV communicating 10 emotions by selecting the correct verbal emotional label. Results show that the level of alexithymia is negatively correlated to the capacity to accurately categorize negative vocalizations, and more particularly sad NEV. On the other hand, negative affectivity appeared negatively correlated with the ability to accurately categorize NEV in general, and negative vocalizations in particular. After splitting the results by the alexithymia level (high vs. low scorers), significant associations between mood and accuracy rates were found in the group of high alexithymia scorers only. These findings support the idea that alexithymic features act across sensory modalities and suggest a mood-interference effect that would be stronger in those individuals.


Assuntos
Afeto , Emoções , Comunicação não Verbal/psicologia , Personalidade , Reconhecimento Psicológico/fisiologia , Choro , Feminino , Humanos , Riso , Masculino , Adulto Jovem
9.
Exp Psychol ; 60(2): 122-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23047920

RESUMO

Recent findings suggest that number processing is intimately linked to space and attention orienting processes. For example, processing numbers induces shifts of spatial attention, with small numbers causing leftward shifts and large numbers causing rightward shifts, suggesting that number magnitude might be represented on a left-to-right mental number line. However, whether inducing spatial attention shifts would in turn influence number production, and whether such influence, if observed, would be restricted to the left-to-right orientation or would extend to an up-to-down orientation in space, remains a matter of debate. The present study assessed whether observing gaze movements, known to moderate spatial attention, was able to influence a random number generation task, and how different directions of the gaze moderated this influence. Participants were asked to randomly produce a number between 1 and 10 after they observed either a horizontal or a vertical eye gaze, or after they observed color changes as a control condition. The results revealed that number production was influenced by the prior presentation of specific gaze changes. Observing leftward or downward gaze led participants to produce more small than large numbers, whereas observing gaze oriented rightward and upward or observing color changes did not influence the magnitude of the numbers produced. These results show that the characteristics of the observed gaze changes primed number magnitude, but that this only held true for some movements, and these were not restricted to the left-to-right axis.


Assuntos
Automatismo/fisiopatologia , Conceitos Matemáticos , Orientação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Tempo de Reação/fisiologia , Adulto , Atenção , Automatismo/psicologia , Movimentos Oculares , Feminino , Humanos , Masculino , Movimento , Estimulação Luminosa/métodos , Adulto Jovem
10.
Res Dev Disabil ; 33(2): 449-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22119692

RESUMO

This study compared mothers and fathers' regulation with respect to 29 children with intellectual disability (ID) and 30 typically developing (TD) children, matched on their mental age (MA), as they solved eight tasks using physical materials and computers. Seven parents' regulatory strategies were coded as they supported their child's identification of the objective, planning, attention, motivation, joint attention, behaviour regulation and evaluation. Children's performance was scored. Regulation by the parents of the two groups did not differ significantly, regardless of the medium, except that the degree of parental regulation of the child's behaviour was greater in the ID group than in the TD group. In tasks involving the computer, we observed a higher degree of regulation of children's planning and a lower degree of regulation of their evaluation for the two groups. The parents displayed significantly less regulation with respect to the children with the highest MA than towards the children with the lowest MA, in each group. There was a significant interaction effect of medium and children's MA on overall parents' regulation and on their support of identification of objective and of planning. Most parental strategies were negatively linked with ID and TD children's performance in tasks. In both groups, with control for MA, parental support with the identification of the objective, with planning and with attention was negatively linked to the corresponding self-regulatory strategies of the children with each medium; however, parents' joint attention was positively linked with children's joint attention.


Assuntos
Deficiência Intelectual/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Pais/psicologia , Resolução de Problemas , Interface Usuário-Computador , Adaptação Psicológica , Adolescente , Adulto , Atenção , Criança , Comportamento Infantil , Feminino , Humanos , Deficiência Intelectual/reabilitação , Masculino , Pessoa de Meia-Idade , Motivação , Autocuidado/psicologia , Adulto Jovem
11.
Res Dev Disabil ; 32(5): 1492-505, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21367576

RESUMO

This study compares self-regulation in 29 children with intellectual disability and 30 typically developing children, who solved tasks using physical materials or computers. Their cognitive, linguistic levels were assessed in order to match the children of both groups. In the presence of their mothers and fathers, the children were asked to perform eight tasks presented using two types of medium (physical materials and computer). Performance and task completion time were recorded. Seven self-regulated strategies were analyzed: identification of objective, planning, self-attention, self-motivation, joint attention, behaviour regulation and self-evaluation. Children in the two groups did not differ in their self-regulation, and in each group, their chronological age had no significant effect on their self-regulation. However, whatever the medium used, their mental age had a significant effect on their overall self-regulation and on six self-regulated strategies: identification of objective, planning, self-attention, self-motivation, behaviour regulation, and self-evaluation. A positive link between overall self-regulation and language abilities was only obtained in the group of typical developers. In addition, although no significant effect of the medium on overall self-regulation was observed in each group, an effect of the type of medium was obtained concerning three specific self-regulated strategies, though not in the same direction: self-attention and self-evaluation are better with the computer than with physical materials, whereas joint attention is better with physical materials than with the computer. In both groups, overall self-regulation, whatever the medium, correlated positively and highly significantly with performance in different tasks (but not with completion time). In each group, variable correlational patterns were obtained between specific self-regulated strategies and performance in each task with each medium: inter-task variability of efficiency of distinct strategies was observed.


Assuntos
Deficiência Intelectual/fisiopatologia , Deficiência Intelectual/psicologia , Destreza Motora/fisiologia , Resolução de Problemas/fisiologia , Desempenho Psicomotor/fisiologia , Autoeficácia , Atitude Frente aos Computadores , Pré-Escolar , Capacitação de Usuário de Computador , Educação Inclusiva/métodos , Feminino , Humanos , Inteligência/fisiologia , Linguística , Masculino
12.
Cognition ; 117(1): 95-100, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20630501

RESUMO

Fingers can be used to express numerical magnitudes, and cultural habits about the fixed order in which fingers are raised determine which configurations become canonical and which non-canonical. Although both types of configuration carry magnitude information, it has been shown that the canonical ones are recognized faster and directly linked to number semantics. Here we tested whether this difference is a consequence of differences in the qualitative way of processing the two types of configurations. When participants named Arabic digits (Experiment 1) or verbal numerals (Experiment 2) primed by canonical and non-canonical finger configurations, qualitatively different priming patterns were observed for the two types of configurations. Canonical configurations activated a place coding representation, with priming spreading to close smaller and larger magnitudes as a function of the prime-target distance. Conversely, non-canonical configurations activated a summation coding representation priming smaller and equal magnitudes independently of the prime-target distance, and larger targets depending on this distance.


Assuntos
Dedos/fisiologia , Adolescente , Sinais (Psicologia) , Feminino , Humanos , Masculino , Matemática , Estimulação Luminosa , Percepção de Tamanho/fisiologia , Adulto Jovem
13.
J Colloid Interface Sci ; 332(1): 91-5, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19128808

RESUMO

The micellization on surfaces of copoly(2-oxazoline) diblock copolymers consisting of a crystallizable poly(2-nonyl-2-oxazoline) (pNonOx) block linked to a poly(2-ethyl-2-oxazoline) (pEtOx) block is investigated. Those micelles are not pre-existing in the initial ethanol solution but are formed during the spin-coating process by the evaporation of the solvent inducing the precipitation of the less soluble pNonOx block. The morphology and size of the surface micelles vary according to the pNonOx molar fraction in the copolymers. Reorganization of the micelles and evolution of the surface energies after a thermal annealing are also studied.

14.
Macromol Rapid Commun ; 30(22): 1871-88, 2009 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21638469

RESUMO

The self-assembly of amphiphilic diblock copolymers in block selective solvents is well documented in the scientific literature. It gives rise to micelles in which the insoluble blocks form a core, which is surrounded by a corona that contains the soluble blocks. Another method to trigger micellization consists in introducing additional non-covalent interactions such as electrostatic interactions or hydrogen bonding in an initially soluble block copolymer. The non-covalent complexes that result from these interactions should be insoluble in order to induce micellization. Such insoluble complexes can be generated by mixing, in a non-selective solvent for all the individual blocks, two block copolymers or a block copolymer and a homopolymer, that contain mutually interacting blocks. This mixing process may, therefore, lead to insoluble non-covalent complexes, which further aggregate into micellar cores stabilized by the uncomplexed blocks. Such a strategy has been successfully implemented in both aqueous and non-aqueous solvents to create interesting stimuli-responsive systems, mainly using ionic interactions and hydrogen bonding. This feature article will summarize these approaches.

15.
Langmuir ; 23(8): 4618-22, 2007 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-17319707

RESUMO

Poly(styrene)-block-poly(4-vinylpyridine) (PS-b-P4VP) copolymers and poly(acrylic acid) (PAA) have been mixed in organic solvents. Complexation via hydrogen bonding occurs between the P4VP and PAA blocks. Those insoluble complexes aggregate to form the core of micelles surrounded by a corona of PS chains. Reorganization of these structures occurs upon addition of acidic or basic water, which results in the breaking of the hydrogen bonds between the P4VP and PAA blocks. After transfer of the initial complexes in acidic water, micelles consisting of a PS core and a protonated P4VP corona are observed. In basic water, well-defined nanoparticles formed by the PS-b-P4VP copolymers are obtained. It is demonstrated that these nanoparticles are stabilized by the negatively charged PAA chains. Finally, thermally induced disintegration of the micelles is investigated in organic solvents.

16.
Therapie ; 60(6): 527-37, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16555489

RESUMO

BACKGROUND: Few data are available on the quality of the protocols promoted by the University Hospital Centers (CHU) in France, and there is no standardised method for evaluating protocol quality. The Clinical Research Centre (CIC) of Nancy developed a checklist-based tool aimed at evaluating the quality of institutional protocols. OBJECTIVE: The objective of this study was to evaluate the performance of this tool for assessing the quality of the protocols promoted by the CHU. METHODS: A prospective parallel-group study design, controlled with cluster randomisation, was used. The checklist was applied within the Directions of Clinical Research (DRC) for 4 months. Sixty four protocols were analysed. RESULTS: Before intervention there was no significant difference in quality scores between the two groups. Compared with baseline, there was a significant improvement of the methodological and regulation median score (81.7 +/- 13.7 vs 90.4 +/- 9.2) only in the intervention group (p = 0.040). Changes in the two groups over time were not significantly different from each other using analysis of variance (p = 0.501). CONCLUSION: In an observation limited to 12 CHU in France, the quality of the promoted protocols was judged as suboptimal and able to be improved. Initiation of quality assurance tools, such as the one used in this study, was associated with some spontaneous improvement, but did not improve the result significantly.


Assuntos
Hospitais Universitários/normas , Garantia da Qualidade dos Cuidados de Saúde/métodos , França , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos
17.
Hum Gene Ther ; 14(9): 883-95, 2003 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-12828859

RESUMO

Inhibition of angiogenesis has been considered among the most promising approaches to treat highly vascularized solid tumors such as glioblastoma. In this study, we designed and validated a new in vitro assay system based on the implantation of tumor cells into organotypic brain slice cultures. We evaluated the effects of local production of three endogenous inhibitors of angiogenesis, angiostatin, endostatin, and interferon (IFN)-alpha(1), using stably transfected rat (9L) and human (GL15) glioblastoma cells on tumor vascularization and growth. Despite similar effectiveness of the three proteins in a classic in vitro endothelial cell migration assay, IFN-alpha(1) demonstrated the most potent antiangiogenic effect in organotypic brain slice cultures. In vivo, after intracerebral implantation of such genetically modified glioblastoma cells, IFN-alpha(1) caused a dramatic decrease in tumor volume revealed by magnetic resonance imaging and by postmortem histology. The mechanisms of this antitumor effect were most likely caused by the major antiangiogenic action of the cytokine, because IFN-alpha(1) expression provoked a pronounced decrease in blood vessel density, which was accompanied by extensive necrosis in the body mass of the tumors. The median survival time of rats implanted intracerebrally with IFN-alpha-expressing 9L cells tripled, and was still significantly increased when these constituted only 1% of transplanted tumor cells. A similar effect was seen when 50% of the transplanted cells were replaced by IFN-alpha-expressing bone marrow stromal cells. These data point to the local delivery of IFN-alpha(1) using cell vectors as a potent tool for the inhibition of tumor-induced angiogenesis.


Assuntos
Inibidores da Angiogênese , Neoplasias Encefálicas/terapia , Colágeno/genética , Glioblastoma/terapia , Interferon-alfa/genética , Fragmentos de Peptídeos/genética , Plasminogênio/genética , Inibidores da Angiogênese/análise , Angiostatinas , Animais , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Células Cultivadas , Colágeno/análise , Endostatinas , Imunofluorescência , Vetores Genéticos , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Interferon-alfa/análise , Imageamento por Ressonância Magnética , Fragmentos de Peptídeos/análise , Plasminogênio/análise , Engenharia de Proteínas , Ratos , Ratos Sprague-Dawley , Retroviridae/genética , Células Tumorais Cultivadas
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