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1.
Respir Care ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906702

RESUMO

Background: This study aimed to describe the use of pressured metered dose inhalers (pMDI) and dry powder inhalers (DPI) in Spanish patients in terms of socio-demographic, clinical, and functional characteristics in patients with asthma or COPD on maintenance treatment with inhaled therapy. Methods: A retrospective, descriptive, national, multicentre, and observational study using a database with 1.8 million patients from hospitals and primary care centers as a secondary information source. Results: The sample included 24,102 subjects with asthma on maintenance therapy (26.0% with pMDI, 54.9% with DPI, and 19.0% with a combination of DPI + pMDI inhalers) and 12,858 subjects with COPD on maintenance therapy (26.1% with pMDI, 38.7% with DPI and 35.2% with a combination of pMDI + DPI inhalers, mostly extemporary triple therapy). In proportion, subjects ≥ 75 years old use more pMDI than DPI, while younger subjects (40-64 years old) use more DPI. An inhalation chamber was prescribed in 51.0% of asthma subjects and 47.2% of COPD subjects treated with pMDI. The use of an inhalation chamber increases with the degree of airflow limitation by disease and age. In subjects with comorbidities, pMDI inhaler use increased in those ≥75 years old for asthma and COPD subjects. Switching from pMDI to DPI and vice versa was relatively common: 25.5% of asthma subjects and 21.9% of COPD subjects treated with pMDI had switched from DPI in the previous year. On the contrary, 14.1% and 11.7% of asthma and COPD patients treated with DPI had switched from pMDI the last year. Conclusions: The use of pMDI or DPI can vary according to age, both in asthma and COPD. Switching from pMDI to DPI and vice versa is relatively common. Despite the availability of dual and triple therapy inhalers on the market, a considerable number of subjects were treated with multiple devices.

2.
Sci Data ; 11(1): 636, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879616

RESUMO

Modelling approaches play a crucial role in supporting local public health agencies by estimating and forecasting vector abundance and seasonality. However, the reliability of these models is contingent on the availability of standardized, high-quality data. Addressing this need, our study focuses on collecting and harmonizing egg count observations of the mosquito Aedes albopictus, obtained through ovitraps in monitoring and surveillance efforts across Albania, France, Italy, and Switzerland from 2010 to 2022. We processed the raw observations to obtain a continuous time series of ovitraps observations allowing for an extensive geographical and temporal coverage of Ae. albopictus population dynamics. The resulting post-processed observations are stored in the open-access database VectAbundance.This initiative addresses the critical need for accessible, high-quality data, enhancing the reliability of modelling efforts and bolstering public health preparedness.


Assuntos
Aedes , Animais , Bases de Dados Factuais , Mosquitos Vetores , Dinâmica Populacional , França , Albânia , Suíça , Itália
3.
Front Public Health ; 12: 1324033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481837

RESUMO

Introduction: Italy was the first European country affected by COVID-19. Thanks to governmental containment measures (9 March 2020), the spread of COVID-19 was limited. However, in this context, accurate data assessment is crucial and mortality is a more reliable indicator of the virus spread compared to the count of positive cases. This study aimed to retrospectively evaluate the impact of the pandemic in different areas of Italy using the time series analysis of official deaths and excess COVID-19 deaths. Methods: Mortality data (23 February-30 April 2022) by Istituto Nazionale di Statistica (ISTAT) were analyzed, including four waves of COVID-19. Previous mortality data (January 2015-November 2019) were used to estimate a Poisson regression model of the pre-pandemic mortality pattern and derive the excess COVID-19 deaths as the difference between the actual deaths number and the extrapolation of the previous mortality pattern to the pandemic period, separately for Northern, Central, and Southern Italy, to compare the impact of mortality across time periods and geographical areas. Results: Estimated excess compared with official COVID-19 mortality shows that, during the first wave, there was an underestimation of deaths. COVID-19 mortality rate almost doubled the official rate in the North (1.60‰ vs. 0.86‰) and nearly tripled it in the South (0.22‰ vs. 0.08‰). In late 2020-early 2021, official and estimated mortality curves are closer, displaying just a small gap at the start of the second wave. During the fourth wave (end of 2021-early 2022), Northern and Central Italy show reasonable agreement; the South presents a large relative underestimation of deaths (+90% increase), with a large increase in its excess deaths national quota, 9% in the first wave to 42% in the fourth. Discussion: The results provide a measure of the COVID-19 excess deaths and an unbiased estimate of Italian mortality rates. In the first wave, the gap between official COVID-19 and excess mortality was particularly high and lockdown measures may have reduced the spread of the infection. In the fourth wave, the gap for the South increases again, probably because the healthcare system may not have coped with the prolonged pressure of the pandemic, or for a decreased compliance with the official paper-based mortality surveillance system that could be overcome in the future by digitalizing the process.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Estudos Retrospectivos , Controle de Doenças Transmissíveis , Itália/epidemiologia
4.
Pharmaceuticals (Basel) ; 16(11)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38004474

RESUMO

INTRODUCTION: Adding LAMA to LABA/ICS is recommended to improve control in patients with persistent asthma. METHODS: This observational, retrospective, before-and-after study considered patients diagnosed with asthma who started LABA/ICS + LAMA treatment (triple therapy, TT) between 1 January 2017 and 31 December 2018 and had been treated with LABA/ICS (dual therapy, DT) in the year before. Changes in lung function and exacerbation rates, healthcare resource utilization, and healthcare and non-healthcare costs (€2019) were estimated in patients with asthma in clinical practices in Spain. Data from computerized medical records from seven Spanish regions were collected ±1 year of LAMA addition. RESULTS: 4740 patients (64.1 years old [SD: 16.3]) were included. TT reduced the incidence of exacerbations by 16.7% (p < 0.044) and the number of patients with exacerbations by 8.5% (p < 0.001) compared to previous DT. The rate of patients with severe exacerbations requiring systemic corticosteroids and their hospitalization rates significantly decreased by 22.5% and 29.5%. TT significantly improved FEV1, FVC, and FEV1/FVC, saving €571/patient for society. Younger patients with asthma (18-44 years old) and patients with severe asthma (FEV1 < 60%) performed better upon the initiation of TT. CONCLUSIONS: TT reduced asthma exacerbations, improved lung function and reduced healthcare costs vs. DT, particularly in patients requiring systemic corticosteroids to treat severe exacerbations.

5.
Glob Chang Biol ; 29(24): 6900-6911, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37804212

RESUMO

The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.


Assuntos
Ecossistema , Gado , Animais , Humanos , Conservação dos Recursos Naturais , Mamíferos , Florestas
6.
Insects ; 14(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37754705

RESUMO

There is broad evidence that the main driver of the ongoing biodiversity crisis is land-use change, which reduces and fragments habitats. The consequence of habitat fragmentation on behavioural responses of fitness-related traits in insects have been so far understudied. In herbivorous insects, oviposition-related behaviours determine access to larval food, and the fate of the next generation. We present a pilot study to assess differences in behaviours related to movement and oviposition in Limenitis camilla butterflies from Wallonia (Belgium), one of the most fragmented regions in Europe. We first quantified variation in functional habitat connectivity across Wallonia and found that fragmented habitats had more abundant, but less evenly distributed host plants of L. camilla. Secondly, we quantified the behaviours of field-caught L. camilla females originating from habitats with contrasted landscape connectivity in an outdoor experimental setting. We found differences in behaviours related to flight investment: butterflies from fragmented woodlands spent more time in departing flight, which we associated with dispersal, than butterflies from homogenous woodlands. Although results from this study should be interpreted with caution given the limited sample size, they provide valuable insights for the advancement of behavioural research that aims to assess the effects of global changes on insects.

7.
J Cogn Neurosci ; 35(8): 1350-1360, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37315334

RESUMO

Our ability to detect targets in the environment fluctuates in time. When individuals focus attention on a single location, the ongoing temporal structure of performance fluctuates at 8 Hz. When task demands require the distribution of attention over two objects defined by their location, color or motion direction, ongoing performance fluctuates at 4 Hz per object. This suggests that distributing attention entails the division of the sampling process found for focused attention. It is unknown, however, at what stage of the processing hierarchy this sampling occurs, and whether attentional sampling depends on awareness. Here, we show that unaware selection between the two eyes leads to rhythmic sampling. We presented a display with a single central object to both eyes and manipulated the presentation of a reset event (i.e., cue) and a detection target to either both eyes (binocular) or separately to the different eyes (monocular). We assume that presenting a cue to one eye biases the selection process to content presented in that eye. Although participants were unaware of this manipulation, target detection fluctuated at 8 Hz under the binocular condition, and at 4 Hz when the right (and dominant) eye was cued. These results are consistent with recent findings reporting that competition between receptive fields leads to attentional sampling and demonstrate that this competition does not rely on aware processes. Furthermore, attentional sampling occurs at an early site of competition among monocular channels, before they are fused in the primary visual cortex.


Assuntos
Atenção , Sinais (Psicologia) , Humanos , Percepção Visual
8.
J Med Chem ; 66(5): 3348-3355, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36808993

RESUMO

The relative success of platinum (Pt)-based chemotherapy comes at the cost of severe adverse side effects and is associated with a high risk of pro-oncogenic activation in the tumor microenvironment. Here, we report the synthesis of C-POC, a novel Pt(IV) cell-penetrating peptide conjugate showing a reduced impact against nonmalignant cells. In vitro and in vivo evaluation using patient-derived tumor organoids and laser ablation inductively coupled plasma mass spectrometry indicates that C-POC maintains robust anticancer efficacy while displaying diminished accumulation in healthy organs and reduced adverse toxicity compared to the standard Pt-based therapy. Likewise, C-POC uptake is significantly lowered in the noncancerous cells populating the tumor microenvironment. This results in the downregulation of versican, a biomarker of metastatic spreading and chemoresistance that we found upregulated in patients treated with standard Pt-based therapy. Altogether, our findings underscore the importance of considering the off-target impact of anticancer treatment on normal cells to improve drug development and patient care.


Assuntos
Antineoplásicos , Platina , Humanos , Platina/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Linhagem Celular Tumoral
9.
Nat Commun ; 14(1): 746, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765091

RESUMO

A substantial proportion of cancer patients do not benefit from platinum-based chemotherapy (CT) due to the emergence of drug resistance. Here, we apply elemental imaging to the mapping of CT biodistribution after therapy in residual colorectal cancer and achieve a comprehensive analysis of the genetic program induced by oxaliplatin-based CT in the tumor microenvironment. We show that oxaliplatin is largely retained by cancer-associated fibroblasts (CAFs) long time after the treatment ceased. We determine that CT accumulation in CAFs intensifies TGF-beta activity, leading to the production of multiple factors enhancing cancer aggressiveness. We establish periostin as a stromal marker of chemotherapeutic activity intrinsically upregulated in consensus molecular subtype 4 (CMS4) tumors and highly expressed before and/or after treatment in patients unresponsive to therapy. Collectively, our study underscores the ability of CT-retaining CAFs to support cancer progression and resistance to treatment.


Assuntos
Antineoplásicos , Fibroblastos Associados a Câncer , Neoplasias Colorretais , Humanos , Fibroblastos Associados a Câncer/patologia , Oxaliplatina/farmacologia , Distribuição Tecidual , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Microambiente Tumoral , Fibroblastos/patologia , Linhagem Celular Tumoral
10.
Parasit Vectors ; 15(1): 414, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348368

RESUMO

Mosquito species belonging to the genus Aedes have attracted the interest of scientists and public health officers because of their capacity to transmit viruses that affect humans. Some of these species were brought outside their native range by means of trade and tourism and then colonised new regions thanks to a unique combination of eco-physiological traits. Considering mosquito physiological and behavioural traits to understand and predict their population dynamics is thus a crucial step in developing strategies to mitigate the local densities of invasive Aedes populations. Here, we synthesised the life cycle of four invasive Aedes species (Ae. aegypti, Ae. albopictus, Ae. japonicus and Ae. koreicus) in a single multi-scale stochastic modelling framework which we coded in the R package dynamAedes. We designed a stage-based and time-discrete stochastic model driven by temperature, photo-period and inter-specific larval competition that can be applied to three different spatial scales: punctual, local and regional. These spatial scales consider different degrees of spatial complexity and data availability by accounting for both active and passive dispersal of mosquito species as well as for the heterogeneity of the input temperature data. Our overarching aim was to provide a flexible, open-source and user-friendly tool rooted in the most updated knowledge on the species' biology which could be applied to the management of invasive Aedes populations as well as to more theoretical ecological inquiries.


Assuntos
Aedes , Humanos , Animais , Aedes/fisiologia , Larva/fisiologia , Espécies Introduzidas , Dinâmica Populacional , Temperatura , Mosquitos Vetores/fisiologia
11.
Transbound Emerg Dis ; 69(5): 2938-2951, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34985810

RESUMO

Ticks have medical and economic importance due to their ability to transmit pathogens to humans and animals. In tropical and sub-tropical countries, tick-borne diseases (TBD) are among the most important diseases affecting livestock and humans. The fast spread of ticks and TBD requires a quick development and application of efficient prevention and/or control programs. Therefore, prior investigations on TBD and related vectors epidemiology, for instance, through accurate epidemiological models, are mandatory. This study aims to develop models to forecast suitable habitat for Rhipicephalus microplus distribution in West Africa. Tick occurrences were assembled from 10 different studies carried out in six West African countries in the past decade. Six statistical models (maximum entropy in a single model and generalised linear model, generalised additive model, random forest, boosted regression tree and support vector machine model in an ensemble model) were applied and compared to predict the habitat suitability of R. microplus distribution in West Africa. Each model was evaluated with the area under the receiver operating characteristic curve (AUC), the true skill statistic (TSS) and the Boyce index (BI). The selected models had good performance according to their AUC (above .8), TSS (above .7) and BI (above .8). Temperature played a key role in MaxEnt model, whereas normalised difference vegetation index (NDVI) was the most important variable in the ensemble model. The model predictions showed coastal countries of West Africa as more suitable for R. microplus. However, some Sahelian areas seems also favourable. We stress the importance of vector surveillance and control in countries that have not yet detected R. microplus but are in the areas predicted to host suitable habitat. Indeed, awareness-raising and training of different stakeholders must be reinforced for better prevention and control of this tick in these different countries according to their status.


Assuntos
Doenças dos Bovinos , Rhipicephalus , Infestações por Carrapato , Doenças Transmitidas por Carrapatos , África Ocidental/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Ecossistema , Humanos , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária
12.
Methods Ecol Evol ; 12(6): 1093-1102, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34262682

RESUMO

Ecosystem heterogeneity has been widely recognized as a key ecological indicator of several ecological functions, diversity patterns and change, metapopulation dynamics, population connectivity or gene flow.In this paper, we present a new R package-rasterdiv-to calculate heterogeneity indices based on remotely sensed data. We also provide an ecological application at the landscape scale and demonstrate its power in revealing potentially hidden heterogeneity patterns.The rasterdiv package allows calculating multiple indices, robustly rooted in Information Theory, and based on reproducible open-source algorithms.

13.
Int J Health Geogr ; 20(1): 29, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127000

RESUMO

BACKGROUND: The COVID-19 pandemic is affecting nations globally, but with an impact exhibiting significant spatial and temporal variation at the sub-national level. Identifying and disentangling the drivers of resulting hospitalisation incidence at the local scale is key to predict, mitigate and manage epidemic surges, but also to develop targeted measures. However, this type of analysis is often not possible because of the lack of spatially-explicit health data and spatial uncertainties associated with infection. METHODS: To overcome these limitations, we propose an analytical framework to investigate potential drivers of the spatio-temporal heterogeneity in COVID-19 hospitalisation incidence when data are only available at the hospital level. Specifically, the approach is based on the delimitation of hospital catchment areas, which allows analysing associations between hospitalisation incidence and spatial or temporal covariates. We illustrate and apply our analytical framework to Belgium, a country heavily impacted by two COVID-19 epidemic waves in 2020, both in terms of mortality and hospitalisation incidence. RESULTS: Our spatial analyses reveal an association between the hospitalisation incidence and the local density of nursing home residents, which confirms the important impact of COVID-19 in elderly communities of Belgium. Our temporal analyses further indicate a pronounced seasonality in hospitalisation incidence associated with the seasonality of weather variables. Taking advantage of these associations, we discuss the feasibility of predictive models based on machine learning to predict future hospitalisation incidence. CONCLUSION: Our reproducible analytical workflow allows performing spatially-explicit analyses of data aggregated at the hospital level and can be used to explore potential drivers and dynamic of COVID-19 hospitalisation incidence at regional or national scales.


Assuntos
COVID-19 , Pandemias , Idoso , Bélgica/epidemiologia , Hospitais , Humanos , Incidência , SARS-CoV-2 , Análise Espaço-Temporal
14.
Prev Vet Med ; 186: 105206, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33261930

RESUMO

Efficient planning of measures limiting epidemic spread requires information on farm locations and sizes (number of animals per farm). However, such data are rarely available. The intensification process which is operating in most low- and middle-income countries (LMICs), comes together with a spatial clustering of farms, a characteristic epidemiological models are sensitive to. We developed farm distribution models predicting both the location and the number of animals per farm, while accounting for the spatial clustering of farms in data-poor countries, using poultry production as an example. We selected four countries, Nigeria, Thailand, Argentina and Belgium, along a gradient of intensification expressed by the per capita Gross Domestic Product (GDP). First, we investigated the distribution of chicken farms along the spectrum of intensification. Second, we built farm distribution models (FDM) based on censuses of commercial farms of each of the four countries, using point pattern and random forest models. As an external validation, we predicted farm locations and sizes in Bangladesh. The number of chicken per farm increased gradually in line with the gradient of GDP per capita in the following order: Nigeria, Thailand, Argentina and Belgium. Interestingly, we did not find such a gradient for farm clustering. Our modelling procedure could only partly reproduce the observed datasets in each of the four sample countries in internal validation. However, in the external validation, the clustering of farms could not be reproduced and the spatial predictors poorly explained the number and location of farms and farm sizes in Bangladesh. Further improvements of the methodology should explore other covariates of the intensity of farms and farm sizes, as well as improvements of the methodology. Structural transformation, economic development and environmental conditions are essential characteristics to consider for an extrapolation of our FDM procedure, as generalisation appeared challenging. We believe the FDM procedure could ultimately be used as a predictive tool in data-poor countries.


Assuntos
Criação de Animais Domésticos/estatística & dados numéricos , Galinhas , Fazendas/estatística & dados numéricos , Criação de Animais Domésticos/métodos , Animais , Argentina , Bélgica , Análise por Conglomerados , Modelos Teóricos , Nigéria , Análise Espacial , Tailândia
15.
Environ Sci Pollut Res Int ; 27(12): 13384-13395, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020451

RESUMO

Atmospheric dispersion model (ADM) simulations are increasingly used as management tools in air pollution monitoring programs, even in the absence of proper validation. Biomonitors can provide important information for ADM validation, but an open question is their temporal frame of application, particularly when native organisms are used. In this study, we tested two alternative ADM simulating the total suspended particulate (TSP) released by a coal power station, against the element content of two native lichens collected at 40 sites, integrated by soil samples. The ADM simulations differed by the time references: the 6-month period preceding lichen sampling, approximately corresponding to the estimated age of the samples (Mod. A), and the whole year 2005, representative of the local average conditions and used in the plant authorization processes (Mod. B). A generalized regression model analysis clearly showed that the Cr, Pb and V content of lichen samples was spatially associated to the outcomes of Mod. A, but not with Mod. B. Interestingly, the Cr content of lichen samples consistently correlated to TSP concentration predicted by Mod. A along two transects placed downwind from the coal power station. This result was corroborated by an air particulate matter sampling which pointed out that air Cr concentrations increased during the operative period of the source. Overall, our results suggest that lichen bioaccumulation data can proficiently be used to validate ADM simulations if the exposure time of the biological samples is consistent with the temporal domain of the ADM simulations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Líquens , Carvão Mineral , Monitoramento Ambiental , Itália
16.
PLoS One ; 15(1): e0221070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31986146

RESUMO

The analysis of census data aggregated by administrative units introduces a statistical bias known as the modifiable areal unit problem (MAUP). Previous researches have mostly assessed the effect of MAUP on upscaling models. The present study contributes to clarify the effects of MAUP on the downscaling methodologies, highlighting how a priori choices of scales and shapes could influence the results. We aggregated chicken and duck fine-resolution census in Thailand, using three administrative census levels in regular and irregular shapes. We then disaggregated the data within the Gridded Livestock of the World analytical framework, sampling predictors in two different ways. A sensitivity analysis on Pearson's r correlation statistics and RMSE was carried out to understand how size and shapes of the response variables affect the goodness-of-fit and downscaling performances. We showed that scale, rather than shapes and sampling methods, affected downscaling precision, suggesting that training the model using the finest administrative level available is preferable. Moreover, datasets showing non-homogeneous distribution but instead spatial clustering seemed less affected by MAUP, yielding higher Pearson's r values and lower RMSE compared to a more spatially homogenous dataset. Implementing aggregation sensitivity analysis in spatial studies could help to interpret complex results and disseminate robust products.


Assuntos
Censos , Gado , Modelos Estatísticos , Animais , Viés , Galinhas , Patos , Humanos , Análise Espacial , Tailândia
17.
Curr Biol ; 29(4): 693-699.e4, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30744973

RESUMO

Attention supports the allocation of resources to relevant locations and objects in a scene. Under most conditions, several stimuli compete for neural representation. Attention biases neural representation toward the response associated with the attended object [1, 2]. Therefore, an attended stimulus enjoys a neural response that resembles the response to that stimulus in isolation. Factors that determine and generate attentional bias have been researched, ranging from endogenously controlled processes to exogenous capture of attention [1-4]. Recent studies investigate the temporal structure governing attention. When participants monitor a single location, visual-target detection depends on the phase of an ∼8-Hz brain rhythm [5, 6]. When two locations are monitored, performance fluctuates at 4 Hz for each location [7, 8]. The hypothesis is that 4-Hz sampling for two locations may reflect a common sampler that operates at 8 Hz globally, which is divided between relevant locations [5-7, 9]. The present study targets two properties of this phenomenon, called rhythmic-attentional sampling: first, sampling is typically described for selection over different locations. We examined whether rhythmic sampling is limited to selection over space or whether it extends to feature-based attention. Second, we examined whether sampling at 4 Hz results from the division of an 8-Hz rhythm over two objects. We found that two overlapping objects defined by features are sampled at ∼4 Hz per object. In addition, performance on a single object fluctuated at 8 Hz. Rhythmic sampling of features did not result from temporal structure in eye movements.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Sinais (Psicologia) , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Periodicidade , Adulto Jovem
18.
Chem Commun (Camb) ; 54(60): 8324-8327, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-29796549

RESUMO

Elevated intra-tumoral immune infiltrate is associated with an improved prognosis in cancer of distinct origins. Traniplatin (TPT) is a novel platinum(iv) pro-drug based on Cisplatin (CDDP) and the marketed drug Tranilast. When compared in vitro to Cisplatin, TPT showed increased cytotoxic activity against colon and lung cancer cells but decreased activity against immune cells. In addition, TPT efficiency was evaluated in tumor explants derived from colorectal cancer samples from patients subjected to intended curative surgery. TPT induced strong intra-tumoral cytotoxic activity yet was associated with an elevated presence of immune cell infiltrate, suggesting a reduced cytotoxic activity against immune cells in colorectal cancer.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Linfócitos do Interstício Tumoral/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/química , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Linfócitos do Interstício Tumoral/imunologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas , ortoaminobenzoatos/química
19.
Molecules ; 22(2)2017 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-28208778

RESUMO

Tumor metastasis is a complex process in which cells detach from the primary tumor and colonize a distant organ. Metastasis is also the main process responsible for cancer-related death. Despite the enormous efforts made to unravel the metastatic process, there is no effective therapy, and patients with metastatic tumors have poor prognosis. In this regard, there is an urgent need for new therapeutic tools for the treatment of this disease. Small molecules with the capacity to reduce cell migration could be used to treat metastasis. Migrastatin-core analogs are naturally inspired macrocycles that inhibit pathological cell migration and are able to reduce metastasis in animal models. Migrastatin analogs can be synthesized from a common advanced intermediate. Herein we present a review of the synthetic approaches that can be used to prepare this key intermediate, together with a review of the biological activity of migrastatin-core analogs and current hypotheses concerning their mechanism of action.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Macrolídeos/química , Macrolídeos/farmacologia , Piperidonas/química , Piperidonas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Produtos Biológicos/síntese química , Produtos Biológicos/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Macrolídeos/síntese química , Macrolídeos/uso terapêutico , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Piperidonas/síntese química , Piperidonas/uso terapêutico
20.
Chem Asian J ; 11(14): 2035-40, 2016 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-27304425

RESUMO

The use of l-sorbose in the synthesis of functionalized cyclopentene derivatives was accomplished. These cyclopentene derivatives are related to those found in naturally occurring jatrophane frameworks and in other bioactive compounds. The formation of allyl α-l-sorbopyranoside was a key synthetic step. Regioselective introduction of protecting groups was followed by the hydrolysis of the allyl glycoside to furnish a fully protected acyclic l-sorbose derivative. This acyclic intermediate was subsequently used to give an orthogonally protected polyhydroxylated cyclopentene, which has potential for further synthesis of bioactive compounds. The protected cyclopentene itself showed a clear cytotoxic activity when tested against a panel of human cancer cell lines (HT29, LS174T, SW620, A549, and HeLa cells).


Assuntos
Antineoplásicos/farmacologia , Ciclopentanos/farmacologia , Sorbose/química , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclopentanos/síntese química , Ciclopentanos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidroxilação , Conformação Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
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