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1.
Environ Pollut ; 333: 121949, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37302782

RESUMO

As filter feeders, marine bivalves inhabiting estuarine and coastal areas are directly exposed to microplastics (MPs) in water. To assess whether MPs number, and their shape, size, colour, and polymer type present in mussels (Mytilus galloprovincialis) and cockles (Cerastoderma edule) varied over one year, bivalves were collected over the year of 2019 in the lower part of the coastal Aveiro lagoon, Portugal. After extraction from the bivalve's whole-body soft tissues, a subset of the visually inspected particles was randomly separated for identification using the Fourier-transform mid-infrared (FT-MIR) spectroscopy. A fraction of the inspected particles, 26-32% of particles >100 µm, and 59-100% of smaller ones were confirmed as MPs. Concentrations varied within the intervals of 0.77-4.3 items g-1 in mussels and 0.83-5.1 items g-1 in cockles, with the lowest values observed in January. In winter, the accumulation of large-sized fibers was composed of a mixture of plastic types, which contrasted against the most abundant MPs in summer consisting mainly of polyethylene of diverse size classes and shapes. Temperature decrease registered in winter might have triggered a lower filtration rate, resulting in lower MPs concentrations in the whole-soft body tissues of organisms. Different properties of MPs found in bivalves between January-February and August-September appear to reflect changes in the characteristics of MPs available in the Aveiro lagoon.


Assuntos
Cardiidae , Mytilus , Poluentes Químicos da Água , Animais , Mytilus/química , Microplásticos , Plásticos , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
3.
Physiotherapy ; 103(1): 81-89, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27083323

RESUMO

OBJECTIVES: To evaluate the effect of manual lymphatic drainage (MLD) on venous flow when applied to the medial and lateral aspects of the thigh and leg in patients with chronic venous insufficiency (CVI) and healthy subjects. DESIGN: Cross-sectional study. SETTING: Participants were assessed in a school-based health community attendant service. PARTICIPANTS: Fifty-seven subjects participated in this study {mean age: 43 [standard deviation (SD) 14] years, 38 women and 19 men}. Of these, 28 subjects had CVI [mean age 47 (SD 12) years] and 29 subjects did not have CVI [mean age 39 (14) years]. INTERVENTION: MLD was applied by a certificated physical therapist to the medial and lateral aspects of the thigh and leg. MAIN OUTCOME MEASUREMENTS: Cross-sectional area; blood flow velocities in the femoral vein, great saphenous vein, popliteal vein and small saphenous vein at baseline and during MLD, measured by duplex ultrasound. RESULTS: Flow volume in the femoral vein increased from baseline [5.19 (SD 3.25)cm3/second] when MLD was applied to the medial [7.03 (SD 3.65)cm3/second; P≤0.001; mean difference -1.69; 95% confidence interval (CI) -2.42 to -0.97] and lateral [6.16 (SD 3.35)cm3/second; P≤0.001; mean difference -1.04; 95% CI -1.70 to -0.39] aspects of the thigh. Venous flow augmentation in the femoral vein and great saphenous vein was higher when MLD was applied to the medial aspect of the thigh (P<0.001), while MLD had a similar effect on venous blood flow regardless of whether it was applied to the medial or the lateral aspect of the leg (P=0.731). CONCLUSIONS: MLD increases blood flow in deep and superficial veins. MLD should be applied along the route of the venous vessels for improved venous return.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Drenagem/métodos , Perna (Membro)/irrigação sanguínea , Manipulações Musculoesqueléticas/métodos , Insuficiência Venosa/reabilitação , Adulto , Estudos Transversais , Feminino , Humanos , Perna (Membro)/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Insuficiência Venosa/diagnóstico por imagem
4.
Phlebology ; 29(4): 247-56, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23455014

RESUMO

OBJECTIVES: To evaluate popliteal vein blood flow during calf muscle contraction in chronic venous disease (CVD) patients and healthy controls using ultrasound imaging and to investigate the relationship between venous blood flow and gastrocnemius muscle (GM) morphology. METHODS: Thirty-one subjects participated in this study (mean age: 40.3 [11.8] years), 15 healthy controls and 16 with CVD (clinical classification: C1₋4). Popliteal vein cross-sectional area and venous blood flow velocity (FV) were evaluated by Doppler ultrasound at baseline and during three sets of 10 tip-toe movement repetitions. Muscle thickness, muscle fascicle length and pennation angle of both medial and lateral GM were measured by ultrasound. Measures were repeated a week later in 17 participants in order to assess reproducibility with intraclass correlation coefficient (ICC) and Bland-Altman analysis. RESULTS: Peak FV was lower in CDV group compared with Control group for both first (40.6 [11.8] versus 62.4 (22.1) cm²/second; P = 0.021) and last (30.4 [9.1] versus 49.5 (22.7) cm²/second; P = 0.024) contraction. In CVD group, peak FV during first contraction increased with GM's muscle fascicle length (r = 0.63; P = 0.041). Popliteal FV also increased with rising range of muscle fascicles pennation change between ankle dorsiflexion and plantar flexion (r = 0.70; P = 0.025). No associations were found between haemodynamics and medial or lateral GM thickness. Calf muscular architecture was similar in both CVD and control participants. Test-retest reliability of FV measured in the same session was high (ICC≈0.70) for measures taken in the first contraction of the set but lowered when using the last contraction (ICC<0.50). Reproducibility of ultrasound evaluation of calf pump is acceptable within the same session but is unsatisfactory when testing in separate days. CONCLUSION: Patients with moderate CVD have lower FV during calf muscles contraction but similar muscle anatomical characteristics compared with healthy controls. Changes in calf muscles flexibility and fatigue resistance may be investigated as possible causes of calf pump dysfunction.


Assuntos
Músculo Esquelético/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Doenças Vasculares/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Feminino , Hemodinâmica , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Veia Poplítea/fisiologia , Reprodutibilidade dos Testes , Doenças Vasculares/fisiopatologia , Veias/fisiologia
5.
Oncogene ; 28(30): 2766-72, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19483723

RESUMO

The tumor suppressor p53 represents a paradigm for gene regulation. Its rapid induction in response to DNA damage conditions has been attributed to both increased half-life of p53 protein and also increased translation of p53 mRNA. Recent advances in our understanding of the post-transcriptional regulation of p53 include the discovery of internal ribosome entry sites (IRESs) within the p53 mRNA. These IRES elements regulate the translation of the full length as well as the N-terminally truncated isoform, p53/47. The p53/47 isoform is generated by alternative initiation at an internal AUG codon present within the p53 ORF. The aim of this review is to summarize the role of translational control mechanisms in regulating p53 functions. We discuss here in detail how diverse cellular stress pathways trigger alterations in the cap-dependent and cap-independent translation of p53 mRNA and how changes in the relative expression levels of p53 isoforms result in more differentiated p53 activity.


Assuntos
Biossíntese de Proteínas , Ribossomos/metabolismo , Proteína Supressora de Tumor p53/fisiologia , Animais , Humanos , Isoformas de Proteínas/fisiologia , RNA Mensageiro/análise , Estresse Fisiológico
6.
Fitoterapia ; 80(2): 130-3, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19166918

RESUMO

A hexane extract from the leaves of Laurus novocanariensis was investigated for its activity on ethanol metabolism in Wistar rats. The extract could interfere with blood ethanol elevation, the induction of gastric alcohol dehydrogenase (ADH) and the reduction of erythrocyte catalase (CAT). The sesquiterpene lactones dehydrocostus lactone and costunolide were identified in the active extract, and might represent its active constituents. These results support the use of L. novocanariensis in the traditional Madeira Island medicine to protect against ethanol injury.


Assuntos
Etanol/sangue , Lactonas/farmacologia , Laurus , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Sesquiterpenos/farmacologia , Álcool Desidrogenase/metabolismo , Animais , Catalase/sangue , Etanol/metabolismo , Esvaziamento Gástrico/efeitos dos fármacos , Hemoglobinas/metabolismo , Lactonas/isolamento & purificação , Laurus/química , Masculino , Folhas de Planta , Substâncias Protetoras/isolamento & purificação , Ratos , Ratos Wistar/sangue , Ratos Wistar/metabolismo , Sesquiterpenos/isolamento & purificação
7.
J Ethnopharmacol ; 121(1): 117-22, 2009 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-18992802

RESUMO

Present study reports on the general bioactivity of strictosamide and on its effects on Na(+),K(+)-ATPase and Mg(2+)-ATPase activities of Charles River male mouse. Strictosamide is the main glycoalkaloid of Sarcocephalus latifolius (Rubiaceae) leaves and roots, used as medicinal plant in folk medicine. In this work, we studied the in vitro effects of various concentrations of strictosamide (0.25, 0.5, 1 or 2 mg/mL) and the in vivo effects of single doses (50, 100 or 200 mg/kg, i.p.) of this compound on kidney and brain Na(+),K(+)-ATPase and Mg(2+)-ATPase activities. Results of general study showed that strictosamide is slightly toxic to Charles River mouse (LD(50)=723.17 mg/kg), producing CNS depression and kidney toxicity, but the exact mechanism of these effects could not be defined. Strictosamide inhibited the in vitro and in vivo Mg(2+)-ATPase activity on kidney but had nonsignificant effect on brain. Furthermore, strictosamide had nonsignificant in vitro and in vivo effect on kidney Na(+),K(+)-ATPase activity but produced an in vivo increase of Na(+),K(+)-ATPase activity of brain, these findings suggesting that strictosamine may be related to the induction of alpha(2) isoform of Na(+),K(+)-ATPase and may account for the folk use of Sarcocephalus latifolius root infusion on hypertension.


Assuntos
Alcaloides/farmacologia , Encéfalo/efeitos dos fármacos , ATPase de Ca(2+) e Mg(2+)/metabolismo , Rim/efeitos dos fármacos , Rubiaceae/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Alcaloides de Vinca/farmacologia , Alcaloides/química , Alcaloides/toxicidade , Animais , Encéfalo/enzimologia , Relação Dose-Resposta a Droga , Rim/enzimologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Raízes de Plantas , Alcaloides de Vinca/química , Alcaloides de Vinca/toxicidade
8.
Oncogene ; 25(52): 6936-47, 2006 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-16983332

RESUMO

P53 controls the growth and survival of cells by acting in response to a multitude of cellular stresses. It is, however, not yet fully understood how different p53 activation pathways result in either cell cycle arrest or apoptosis. We and others have described an N-terminally truncated p53 protein (p53/47) originating from a second translation initiation site in the p53 messenger RNA (mRNA), which can interact with p53 and impose altered stability and transactivation properties to p53 complexes. Here we show that cap-dependent and cap-independent mechanisms of initiation govern the translation of the p53 mRNA. Changes in synthesis of full-length p53 or p53/47 are regulated through distinct cell stress-induced pathways acting through separate regions of the p53 mRNA. We also show that some cytotoxic drugs require the presence of full-length p53 to induce apoptosis, whereas for others p53/47 is sufficient. This indicates that by harbouring alternative translation initiation sites, the p53 mRNA gives rise to different levels of the p53 isoforms which help to orchestrate the cell biological outcome of p53 activation in response to different types of cell stress. This sheds new light into the way p53 can integrate and differentiate a large multiplicity of changes in the cellular environment.


Assuntos
Regulação da Expressão Gênica/genética , Biossíntese de Proteínas/fisiologia , Isoformas de Proteínas/genética , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/genética , Regiões 5' não Traduzidas , Northern Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Chromatogr A ; 889(1-2): 51-7, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10985535

RESUMO

The adsorption and desorption capacities of 11 different solid-phase extraction sorbents were tested for the preconcenration of pigments of various Hungarian red wines. The concentrates were evaluated by multiwavelengh spectrophotometry combined with a spectral mapping technique (SPM) and by reversed-phase high-performance liquid chromatography. The highest (10-fold) concentration of pigments was achieved on octadecylsilica sorbent. It can be used five times without losing adsorption and desorption characteristics. SPM indicated that multiwavelength spectrophotometry can be employed for the differentiation of red wines. Comparison of the chromatograms of pigments with and without preconcentration showed that preconcentration makes possible the separation and detection of pigments present in low concentration in red wines.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pigmentos Biológicos/isolamento & purificação , Vinho/análise , Análise Espectral , Vinho/classificação
10.
J Chromatogr Sci ; 38(4): 145-50, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10766480

RESUMO

The soluble color pigments of raisin are separated by reversed-phase thin-layer chromatography (TLC), and the capacity of TLC-Fourier transform infrared (FTIR) with both on-line and off-line coupling is assessed for the identification of the main fraction. TLC has also been used as a pilot technique for the development of a gradient elution method for the separation of pigments by high-performance liquid chromatography (HPLC). On-line TLC-FTIR cannot be used for identification because of the strong adsorbance of the stationary phase. Off-line TLC-FTIR combined with the retention behavior of the main pigment fraction indicates that it is a polymer, caramel-like compound composed of erythrose and fructose monomers. Baseline separation of pigments is achieved by HPLC using TLC as a pilot method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Frutas/química , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
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