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1.
Environ Technol ; : 1-10, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37441776

RESUMO

The present study evaluated the effect of the Fenton process as pretreatment for metronidazole (MNZ) removal coupled with a phytoremediation system using Scirpus lacustris as macrophyte. Initial concentrations of 0.5, 5, 10, 15, and 20 mg MNZ/L were studied in batch cultures. Results obtained in the MNZ removal by phytoremediation showed efficiencies of 93 ± 2%, 81 ± 4%, 85 ± 1%, 84 ± 2%, and 87 ± 6%, respectively. The metronidazole pretreated by the Fenton process and subsequently fed to the phytoremediation system increased the removal efficiencies up to 93 ± 3%, 99 ± 1%, 99 ± 4%, 94 ± 2%, and 94 ± 3%, respectively. Individual studies with Scirpus lacustris in touch with metronidazole displayed relative growth rates of 0.02-0.04 d-1, showing the not toxic effect of the antibiotic on the macrophyte growth. On the other hand, the BMG kinetic model best describes the removal of MNZ by phytoremediation. Finally, applying the Fenton process as a pretreatment makes the MNZ more assimilable for the phytoremediation system, converting the integration of Fenton with the phytoremediation like other attractive technology to be considered in removing emerging compounds.

2.
Nat Commun ; 14(1): 2146, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081049

RESUMO

Animal tolerance towards humans can be a key factor facilitating wildlife-human coexistence, yet traits predicting its direction and magnitude across tropical animals are poorly known. Using 10,249 observations for 842 bird species inhabiting open tropical ecosystems in Africa, South America, and Australia, we find that avian tolerance towards humans was lower (i.e., escape distance was longer) in rural rather than urban populations and in populations exposed to lower human disturbance (measured as human footprint index). In addition, larger species and species with larger clutches and enhanced flight ability are less tolerant to human approaches and escape distances increase when birds were approached during the wet season compared to the dry season and from longer starting distances. Identification of key factors affecting animal tolerance towards humans across large spatial and taxonomic scales may help us to better understand and predict the patterns of species distributions in the Anthropocene.


Assuntos
Animais Selvagens , Comportamento Animal , Aves , Ecossistema , Interação Humano-Animal , Animais , Humanos , Animais Selvagens/fisiologia , Animais Selvagens/psicologia , Austrália , Aves/fisiologia , População Urbana , África , América do Sul , População Rural , Clima Tropical
3.
Osteoarthritis Cartilage ; 30(12): 1658-1669, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36108937

RESUMO

OBJECTIVE: Intra-articular corticosteroid injections (IACIs) provide temporary symptom relief in osteoarthritis (OA). This meta-analysis investigated the effects of recurrent IACIs at 3 months and beyond. DESIGN: We searched Medline, Embase and Cochrane from inception to January 2021 for randomised controlled trials (RCTs) of patients with OA who received recurrent IACIs compared with other injectables, placebo or no treatment (primary outcomes: pain, function). Mean differences (MDs) with 95% confidence intervals were reported. RESULTS: Ten RCTs were included (eight knee OA (n = 763), two trapeziometacarpal OA (n = 121)). Patients received between 2 and 8 injections, varying by trial. Trials compared recurrent IACIs with hyaluronic acid (HA), platelet-rich plasma (PRP), saline or orgotein (follow-up 3-24 months). Greater improvements in pain, function and QoL at 3-24 months were noted for the comparators than with IACIs, with comparators demonstrating an equal or superior effect, or the intervention effect attenuated during follow-up. Recurrent IACIs demonstrated no benefits in pain or function over placebo at 12-24 months. No serious adverse events were recorded. No studies reported on time-to-future interventions, risk of future prosthetic joint infection or other adverse events associated with subsequent joint replacement. CONCLUSIONS: Recurrent IACIs often provide inferior (or non-superior) symptom relief compared with other injectables (including placebo) at 3 months and beyond. Other injectables (HA, PRP) often yielded greater improvements in pain and function up to 24 months post-injection. Existing RCTs on recurrent IACIs lack sufficient follow-up data to assess disease progression and time-to-future interventions.


Assuntos
Osteoartrite do Joelho , Plasma Rico em Plaquetas , Humanos , Injeções Intra-Articulares , Osteoartrite do Joelho/terapia , Ácido Hialurônico , Corticosteroides/uso terapêutico , Dor/tratamento farmacológico , Resultado do Tratamento
4.
Cell Rep ; 32(7): 108047, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32814050

RESUMO

Oligodendrogenesis occurs during early postnatal development, coincident with neurogenesis and synaptogenesis, raising the possibility that microglia-dependent pruning mechanisms that modulate neurons regulate myelin sheath formation. Here we show a population of ameboid microglia migrating from the ventricular zone into the corpus callosum during early postnatal development, termed "the fountain of microglia," phagocytosing viable oligodendrocyte progenitor cells (OPCs) before onset of myelination. Fractalkine receptor-deficient mice exhibit a reduction in microglial engulfment of viable OPCs, increased numbers of oligodendrocytes, and reduced myelin thickness but no change in axon number. These data provide evidence that microglia phagocytose OPCs as a homeostatic mechanism for proper myelination. A hallmark of hypomyelinating developmental disorders such as periventricular leukomalacia and of adult demyelinating diseases such as multiple sclerosis is increased numbers of oligodendrocytes but failure to myelinate, suggesting that microglial pruning of OPCs may be impaired in pathological states and hinder myelination.


Assuntos
Microglia/metabolismo , Bainha de Mielina/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Animais , Diferenciação Celular , Masculino , Camundongos , Células-Tronco
5.
J Transl Med ; 18(1): 1, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900168

RESUMO

The present review aimed to discuss contemporary scientific literature involving differences between the tumor microenvironment (TME) in melanoma, lung cancer, and breast cancer in their primary site and TME in brain metastases (BM). TME plays a fundamental role in the behavior of cancer. In the process of carcinogenesis, cells such as fibroblasts, macrophages, endothelial cells, natural killer cells, and other cells can perpetuate and progress carcinogenesis via the secretion of molecules. Oxygen concentration, growth factors, and receptors in TME initiate angiogenesis and are examples of the importance of microenvironmental conditions in the performance of neoplastic cells. The most frequent malignant brain tumors are metastatic in origin and primarily originate from lung cancer, breast cancer, and melanoma. Metastatic cancer cells have to adhere to and penetrate the blood-brain barrier (BBB). After traversing BBB, these cells have to survive by producing various cytokines, chemokines, and mediators to modify their new TME. The microenvironment of these metastases is currently being studied owing to the discovery of new therapeutic targets. In these three types of tumors, treatment is more effective in the primary tumor than in BM due to several factors, including BBB. Understanding the differences in the characteristics of the microenvironment surrounding the primary tumor and their respective metastasis might help improve strategies to comprehend cancer.


Assuntos
Neoplasias Encefálicas , Microambiente Tumoral , Carcinogênese , Células Endoteliais , Humanos , Neovascularização Patológica
6.
J Perinatol ; 37(1): 42-48, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27711042

RESUMO

OBJECTIVE: To investigate the effects of fortification and storage on nutrients and properties of various human milk (HM) types. STUDY DESIGN: Mother's own milk (MOM) and pasteurized donor human milk (DHM; n=118) were analyzed pre- and post fortification with Enfamil and Similac human milk fortifier (EHMF and SHMF) before and after 24 h of refrigerated storage. RESULTS: Milk fortified with SHMF had significantly greater osmolality, pH and lipase activity than EHMF. Changes in protein, pH and osmolality following refrigerated storage differed between fortifiers. When milk type was factored into the analysis, protein and lipase activity changes in fresh MOM differed significantly from DHM and frozen MOM. Analysis of UNF HM found higher protein levels in preterm vs term samples and in MOM vs DHM. CONCLUSION: Nutrient composition of HM varies significantly by milk type. Although fortifiers enhance select nutrients, each has the potential to affect HM properties in a unique way and these affects may vary by milk type.


Assuntos
Alimentos Fortificados/análise , Recém-Nascido Prematuro/crescimento & desenvolvimento , Proteínas do Leite/análise , Leite Humano/química , Valor Nutritivo , Feminino , Armazenamento de Alimentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Lactente , Recém-Nascido , Refrigeração
7.
Scand J Med Sci Sports ; 25(6): e655-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25441263

RESUMO

This study was a preliminarily investigation into the prevention of unintentional doping on the basis of self-determination theory (SDT). Specifically, we examined the relationship between athletes' motives for doping avoidance and their behavior when offered an unfamiliar food product. Participants were young Australian athletes (n = 410) that were offered a free lollipop prior to completing a questionnaire. It was noted whether participants refused to take or eat the lollipop and whether they read the ingredients of the lollipop. The questionnaire assessed autonomous and controlled forms of motivation, amotivation, doping intentions, and adherence regarding doping avoidance behaviors. The results showed that young athletes who adopted controlled reasons to avoid doping in sport (e.g., not getting caught) tended to report higher adherence to behaviors related to avoiding and monitoring banned substances, whereas those who adopted autonomous reasons (e.g., anti-doping being consistent with life goals) appeared to be more willing to read the ingredients of the provided food. The significant interaction effect between autonomous and controlled motivation indicated that autonomous motivation was more predictive to doping intention for athletes with low controlled motivation. It is concluded that SDT may help understand the motivational processes of the prevention of unintentional doping in sport.


Assuntos
Atletas/psicologia , Dopagem Esportivo/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Motivação , Autonomia Pessoal , Adolescente , Doces , Dopagem Esportivo/prevenção & controle , Comportamento Alimentar , Feminino , Rotulagem de Alimentos , Humanos , Intenção , Masculino , Teoria Psicológica , Inquéritos e Questionários , Adulto Jovem
8.
J Sci Med Sport ; 18(3): 315-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24793786

RESUMO

OBJECTIVES: Motivation in sport has been frequently identified as a key factor of young athletes' intention of doping in sport, but there has not been any attempt in scrutinizing the motivational mechanism involved. The present study applied the trans-contextual model of motivation to explain the relationship between motivation in a sport context and motivation and the social-cognitive factors (attitude, subjective norm, perceived behavioral control, and intention) from the theory of planned behavior (TPB) in an anti-doping context. DESIGN: A cross-sectional survey was conducted. METHODS: Questionnaire data was collected from 410 elite and sub-elite young athletes in Australia (Mean age [17.7±3.9 yr], 55.4% male, Years in sport [9.1±3.2]). We measured the key model variables of study in relation to sport motivation (Behavioral Regulation in Sport Questionnaire), and the motivation (adapted version of the Treatment Self-Regulation Questionnaire) and social cognitive patterns (the theory of planned behavior questionnaire) of doping avoidance. The data was analyzed by variance-based structural equation modeling with bootstrapping of 999 replications. RESULTS: The goodness-of-fit of the hypothesized model was acceptable. The bootstrapped parameter estimates revealed that autonomous motivation and amotivation in sport were positively associated with the corresponding types of motivation for the avoidance of doping. Autonomous motivation, subjective norm, and perceived behavioral control in doping avoidance fully mediated the relationship between autonomous motivation in sport and intention for doping avoidance. CONCLUSIONS: The findings support the tenets of the trans-contextual model, and explain how motivation in sport is related to athletes' motivation and intention with respect to anti-doping behaviors.


Assuntos
Desempenho Atlético/psicologia , Dopagem Esportivo/psicologia , Motivação , Autonomia Pessoal , Esportes/psicologia , Adolescente , Atitude , Aprendizagem da Esquiva , Comportamento de Escolha , Estudos Transversais , Feminino , Humanos , Intenção , Masculino , Modelos Psicológicos , Adulto Jovem
9.
J Perinatol ; 34(8): 624-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24762411

RESUMO

OBJECTIVE: To determine emission of volatile organic compounds (VOCs) from plastic medical equipment within an incubator. STUDY DESIGN: Air samples from incubators before and after adding medical equipment were analyzed using EPA TO-15 methodology. Headspace analysis was used to identify VOC emissions from each medical equipment item. Air changes per hour (ACH) of each incubator were determined and used to calculate the emission rate of identified VOCs. RESULTS: Cyclohexanone was identified in all incubator air samples. At 28 °C, the mean concentration before and after adding medical equipment items was 2.1 ± 0.6 and 57.2 ± 14.9 µg m(-3),respectively (P<0.01). Concentrations increased to a mean of 83.8 ± 23.8 µg m(-)(3) (P<0.01) at 37(o)C and 93.0 ± 45.1 µg m(-)(3) (P=0.39) after adding 50% humidity. Intravenous tubing contributed 89% of cyclohexanone emissions. ACH were determined with access doors closed and open with means of 11.5 ± 1.7 and 44.1 ± 6.7 h(-1), respectively. Cyclohexanone emission rate increased from a mean of 102.2 µg h(-1) at 28(°C to 148.8 µg h(-1) (P<0.01) at 37 °C. CONCLUSION: Cyclohexanone was quantified in all incubator air samples containing plastic medical equipment. The concentration of cyclohexanone within the incubator was inversely related to ACH in the closed mode. The cyclohexanone concentration as well as the emission rate increased with higher temperature.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise , Incubadoras para Lactentes , Compostos Orgânicos Voláteis/análise , Roupas de Cama, Mesa e Banho , Leitos , Monitoramento Ambiental , Plásticos
10.
Pediatr Obes ; 9(2): e47-57, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23630014

RESUMO

OBJECTIVES: To assess pre-adolescent children's responses to common child-oriented front-of-pack food promotions. METHODS: Between-subjects, web-based experiment with four front-of-pack promotion conditions on energy-dense and nutrient-poor (EDNP) foods: no promotion [control]; nutrient content claims; sports celebrity endorsements (male athletes) and premium offers. Participants were 1302 grade 5 and 6 children (mean age 11 years) from Melbourne, Australia. Participants chose their preferred product from a randomly assigned EDNP food pack and comparable healthier food pack then completed detailed product ratings. Child-oriented pack designs with colourful, cartooned graphics, fonts and promotions were used. RESULTS: Compared to the control condition, children were more likely to choose EDNP products featuring nutrient content claims (both genders) and sports celebrity endorsements (boys only). Perceptions of nutritional content were enhanced by nutrient content claims. Effects of promotions on some product ratings (but not choice) were negated when children referred to the nutrition information panel. Premium offers did not enhance children's product ratings or choice. CONCLUSIONS: Nutrient content claims and sports celebrity endorsements influence pre-adolescent children's preferences towards EDNP food products displaying them. Policy interventions to reduce the impact of unhealthy food marketing to children should limit the use of these promotions.


Assuntos
Atletas , Comportamento de Escolha , Pessoas Famosas , Indústria Alimentícia/métodos , Rotulagem de Alimentos , Preferências Alimentares , Valor Nutritivo , Adolescente , Publicidade , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Feminino , Humanos , Masculino , Marketing , Distribuição por Sexo , Inquéritos e Questionários
11.
Neuroradiol J ; 23(5): 554-73, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24148677

RESUMO

Infectious diseases of the central nervous system vary in frequency in different locations in America and Europe. What is common in Brazil can be a sporadic presentation in Europe. Cooperative work gathering experiences from neuroradiologists working in various places can be achieved and will help to identify uncommon cases that can present in our daily practice.

12.
Tob Control ; 18(3): 218-21, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19264731

RESUMO

OBJECTIVE: To assess the influence of point-of-sale (POS) cigarette displays on unplanned purchases. METHODS: Intercept interviews were conducted with customers observed purchasing cigarettes from retail outlets featuring POS cigarette displays. Measures included intention to purchase cigarettes prior to entering the store, unprompted and prompted salience of POS tobacco displays, urge to buy cigarettes as a result of seeing the POS display, brand switching and support for a ban on POS cigarette displays. RESULTS: In total, 206 daily smokers aged 18-76 years (90 male, 116 female) were interviewed. Unplanned cigarette purchases were made by 22% of participants. POS displays influenced nearly four times as many unplanned purchases as planned purchases (47% vs 12%, p<0.01). Brand switching was reported among 5% of participants, half of whom were influenced by POS displays. Four times as many smokers were supportive of a ban on POS tobacco displays than unsupportive (49% vs 12%), and 28% agreed that such a ban would make it easier to quit. CONCLUSIONS: POS tobacco displays act as a form of advertising even in the absence of advertising materials. They stimulate unplanned cigarette purchases, play an important role in brand selection and tempt smokers trying to quit. This justifies removing POS tobacco displays from line of sight-something that very few smokers in our sample would object to.


Assuntos
Comércio/economia , Comportamento Impulsivo/economia , Fumar/economia , Adolescente , Adulto , Idoso , Sinais (Psicologia) , Feminino , Humanos , Comportamento Impulsivo/psicologia , Masculino , Pessoa de Meia-Idade , Fumar/psicologia , Responsabilidade Social , Adulto Jovem
13.
J Hosp Infect ; 72(1): 36-42, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19282058

RESUMO

In recent years, explicit behavioural theories have been used in some research into hand hygiene behaviour. One of the most prominent of these has been the theory of planned behaviour (TPB). In this qualitative study aimed at increasing understanding of infection prevention practice in the acute care setting, TPB was identified as a suitable framework for the emergence of new insights that have the potential to improve the power of existing education and training. The theory emerging from the research was based on a finding that individual experience is of greater import than formal education in explaining hand hygiene behaviour. This indicated that exposure to vivid vicarious experience is a potential means to improving the power of existing training methods and increasing the propensity for instilling sustainable adequate hand hygiene habits.


Assuntos
Atitude do Pessoal de Saúde , Infecção Hospitalar/prevenção & controle , Educação/métodos , Fidelidade a Diretrizes/estatística & dados numéricos , Desinfecção das Mãos , Acontecimentos que Mudam a Vida , Infecção Hospitalar/transmissão , Feminino , Humanos , Masculino
14.
Scott Med J ; 53(4): 7-10, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19051656

RESUMO

OBJECTIVE: Young children may develop renal scarring following a urinary tract infection (UTI) especially after pyelonephritis which is difficult to diagnose. Permanent renal scars are diagnosed by dimercapto-succinic acid (DMSA) scan several months later. To decrease unnecessary exposure to radiation, we investigate the role of renal power Doppler (RPD) in predicting those who may not require a late DMSA scan. METHODS: Children under four years of age with a first UTI underwent an RPD study soon after diagnosis, and a DMSA scintigraphy six months later. The predictive values of the early RPD to detect DMSA renal scarring were calculated. RESULTS: Twenty three children (median age 30 months) were enrolled: 13 had a febrile presentation, two with bacteraemia. Permanent scarring occurred in three children (13%). In the 46 kidney units studied, initial RPD was abnormal in two and late DMSA abnormal in three units. Overall concordance between RPD and DMSA was 93.5%. The sensitivity of RPD for renal scar as per DMSA was 33.3%, specificity 97.7%; positive predictive value 50% and a negative predictive value of 95.4%. CONCLUSIONS: RPD offered no advantage over ultrasound to predict renal scarring and cannot be recommended to predict renal scarring following UTI.


Assuntos
Cicatriz/diagnóstico por imagem , Rim/diagnóstico por imagem , Ultrassonografia Doppler , Infecções Urinárias/complicações , Pré-Escolar , Cicatriz/etiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Cintilografia , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Ácido Dimercaptossuccínico Tecnécio Tc 99m
15.
Int J STD AIDS ; 19(11): 780-1, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931274

RESUMO

In hepatitis B virus (HBV) monoinfection, alanine aminotransferase (ALT) levels are linearly correlated with HBV DNA levels and lamivudine resistance. In human immunodeficiency virus (HIV)/HBV co-infection, little is known about the association between ALT, HBV DNA, and lamivudine resistance. We assessed HBV DNA, lamivudine resistance and ALT levels in 45 time points in 11 patients with HIV/HBV co-infection during lamivudine-containing antiretroviral therapy. High HBV DNA levels (>10(6) copies/mL) and lamivudine resistance developed in 45% and 91% of patients, respectively. However, ALT levels were not elevated in the setting of high HBV DNA levels (mean ALT, 48 IU/mL) or lamivudine resistance (mean ALT, 44 IU/mL). HBV viraemia and lamivudine resistance during extended lamivudine-containing antiretroviral therapy are common in HIV/HBV co-infection, occurring in the absence of significant ALT elevations. In HIV/HBV co-infection, measurement of HBV DNA and HBV resistance mutations may identify HBV virological failure before biochemical changes and should be routinely used in the management of HIV/HBV co-infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/sangue , Alanina Transaminase/sangue , DNA Viral/sangue , Infecções por HIV/sangue , Hepatite B/sangue , Adulto , Fármacos Anti-HIV/farmacologia , Terapia Antirretroviral de Alta Atividade , Auditoria Clínica , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Lamivudina/farmacologia , Masculino , Pessoa de Meia-Idade
16.
J Perinatol ; 28(8): 534-40, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18563165

RESUMO

OBJECTIVE: To identify and quantify airborne volatile organic compounds (VOCs) inside neonatal incubators during various modes of operation within the neonatal intensive care unit (NICU) environment. STUDY DESIGN: Air samples were taken from 10 unoccupied incubators in four operational settings along with ambient air samples using air sampling canisters. The samples were analyzed following EPA TO-15 using a Tekmar AutoCan interfaced to Agilent 6890 Gas Chromatograph with a 5973 Mass Spectrometer calibrated for 60 EPA TO-15 method target compounds. Non-target compounds were tentatively identified using mass spectral interpretation and with a mass spectral library created by National Institute for Standards and Technology. RESULT: Two non-target compounds, 2-heptanone and n-butyl acetate, were found at elevated concentrations inside the incubators compared with ambient room air samples. Increase in temperature and addition of humidity produced further increased concentrations of these compounds. Their identities were verified by mass spectra and relative retention times using authentic standards. They were quantified using vinyl acetate and 2-hexanone as surrogate standards. CONCLUSION: The emission pattern of these two compounds and background measurements indicate that they originate inside the incubator. There is evidence that exposure to some VOCs may adversely impact the fetal and developing infants' health. Currently, as there is no definitive information available on the effects of acute or chronic low-level exposure to these compounds in neonates, future studies evaluating the health effects of neonatal exposure to these VOCs are needed.


Assuntos
Acrilatos/análise , Poluição do Ar em Ambientes Fechados/análise , Incubadoras para Lactentes/efeitos adversos , Cetonas/análise , Monitoramento Ambiental , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Plásticos/efeitos adversos , Plásticos/química , Volatilização
17.
Int J Cancer ; 121(9): 1903-1909, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17631645

RESUMO

Aberrant expression/localisation of beta-catenin has been implicated in the progression of oesophageal cancer. As a member of the Wnt-signalling pathway, activated beta-catenin translocates into the nucleus and drives gene transcription. Insulin-like growth factors (IGFs) have been implicated in modulation of beta-catenin localisation and transcriptional activity. We have demonstrated that beta-catenin is abundantly expressed by oesophageal cancer cells, and is both cytoplasmic and nuclear in location. beta-catenin was transcriptionally inactive in 4 of 5 cell lines. All cells expressed the IGF-1 receptor. Addition of exogenous IGFs activated the PI-3 kinase pathway but did not enhance beta-catenin/T-cell factor- (TCF) mediated transcription. Activation of Wnt signalling by lithium induced beta-catenin stabilisation in 2 cell lines but this did not increase transcriptional activity. In contrast 2 cell lines without lithium-enhanced stabilisation or re-distribution of beta-catenin did exhibit beta-catenin/TCF-mediated transcriptional activity. This study shows that beta-catenin accumulation and nuclear localisation is not indicative of transcriptional activity, and therefore is not supportive of a major role in these oesophageal cancer cells. It also questions the value of immunohistochemical studies that examine only expression. Co-operative signalling from other growth factors or adhesive molecules is likely to be required to relieve nuclear inhibition of transcriptional activity, and the nature of this is currently unknown.


Assuntos
Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Transcrição Gênica/genética , beta Catenina/genética , beta Catenina/metabolismo , Transporte Ativo do Núcleo Celular , Linhagem Celular Tumoral , Neoplasias Esofágicas/genética , Genes Reporter/genética , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Ligantes , RNA Mensageiro/genética , Fatores de Transcrição TCF/genética
18.
J Environ Manage ; 85(1): 44-58, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16996198

RESUMO

Trees have been widely quoted as effective scavengers of both gaseous and particulate pollutants from the atmosphere. Recent work on the deposition of urban aerosols onto woodland allows the effect of tree planting strategies on airborne aerosol concentrations to be quantified and considered within the planning process. By identifying the potential planting locations in the local authority area, and applying them within a dispersion and deposition model, the potential magnitude of reduction in the ambient concentration of PM(10), achievable through urban tree planting, has been quantified for two UK cities. As part of the Environmental Information Systems for Planners (EISP), flow diagrams, based on planning decisions, have incorporated output from the model to make decisions on land use planning ranging from development plans and strategic planning, to development control. In this way, for any new developments that contribute to the local PM(10) level, the mitigation by planting trees can be assessed, and in some cases, reductions can be sufficient to meet air quality objectives for PM(10).


Assuntos
Poluição do Ar/prevenção & controle , Técnicas de Apoio para a Decisão , Material Particulado , Árvores , Poluentes Atmosféricos/análise , Bases de Dados Factuais , Tamanho da Partícula , Material Particulado/análise , Reino Unido
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