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1.
Environ Pollut ; 331(Pt 1): 121936, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37263563

RESUMO

Although aluminum is widely distributed in the earth's crust, its environmental availability and wildlife assimilation rates are only partially known. Here we analyze aluminum concentrations in bone from 10 species of marine mammals inhabiting 3 geographic areas subject to different aluminum inputs: the Río de la Plata estuary (Uruguay), the coastal waters of Mauritania and the Galapagos archipelago (Ecuador). Overall, concentrations were unusually high as compared to those of terrestrial animals, with lowest concentrations in the Galapagos archipelago, then the Río de la Plata estuary and finally Mauritania. The aluminum source varied between regions, prevailing anthropogenic sources in the Río de la Plata Estuary and natural sources (wind-blown dust) in Mauritanian waters. The type of source determined contamination levels: anthropogenic sources were most significant for coastal species and showed a decline with distance of habitat from shoreline, while natural sources had a higher influence on open waters because of the dearth of biogenic silica that eliminates aluminum from the water column. Since aluminum remains in bone for several decades, marine mammal bone reflects historical levels of aluminum and therefore is a good bioindicator of the aluminum concentration of the marine environment.


Assuntos
Alumínio , Ecossistema , Animais , Uruguai , Estuários , Mamíferos , Monitoramento Ambiental
2.
Ecotoxicol Environ Saf ; 207: 111085, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32898814

RESUMO

Previous studies showed contradictory results of static magnetic field (SMF) influence on behavior, hematological parameters and organ damage. The aim of this study was to investigate influence of subchronic continuous exposure to upward and downward oriented SMF of moderate intensity on behavior, hematological characteristics, heart and kidney tissue of spontaneously hypertensive rats. SH rats exposed to downward oriented SMF demonstrated lack of anxious-like behavior. SMF of either orientation caused decrease in the number of platelets in peripheral blood, granulocytes in the spleen and bone marrow and increase in the number of erythrocytes in the spleen, in both exposed groups. We also demonstrated that spontaneously hypertensive rats exposed to upward oriented SMF exhibited decreased lymphocytes count in blood, decreased bone marrow erythrocytes count and rats exposed to downward oriented SMF had increased lymphocytes count in bone marrow. The results showed adverse effect of differently oriented SMF on hematological parameters of spontaneously hypertensive rats. Also, exposure to different oriented SMF didn't affect their heart and kidney morphological characteristics.


Assuntos
Hipertensão , Campos Magnéticos/efeitos adversos , Animais , Ratos , Ratos Endogâmicos SHR , Baço
3.
Med. intensiva (Madr., Ed. impr.) ; 44(2): 96-100, mar. 2020. tab
Artigo em Inglês | IBECS | ID: ibc-188658

RESUMO

Background: Central venous cannulation (CVC) is common and necessary in pediatric intensive care. However, this procedure is not without risks or complications. Although CVCs have classically been placed following anatomical landmarks, the use of ultrasound guidance has largely replaced the latter, given its better profile of efficacy and safety, demonstrated at least in adult populations. Objectives: To compare the effectiveness and safety in the insertion of femoral central venous catheters guided by ultrasound (US) versus the anatomical method (LM) in critical care pediatric patients. Methods: 100 patients were randomized: 50 were assigned to the US group and 49 to the LM group. In the LM group the traditional method consisted in palpating the femoral artery pulse as a; in the US group the CVC was inserted using a real time technique. Success at the first attempt, overall success in cannulation, number of attempts and arterial puncture were the variables studied in both groups. Results: Success at the first attempt and overall success in cannulation were significantly higher in the US group versus the LM (US 42% vs. LM 18%, p 0.011, US 84% vs. LM 51% p <0.001, respectively). The incidence of puncture of the femoral artery was lower in the US group (LM 12 vs. US 5, p 0.056) without achieving statistical significance. Conclusions: According to our results, the placement of central venous access via the femoral approach should be preferably performed under ultrasound guidance, however, further studies in larger populations are needed to confirm this findings


Antecedentes: La instalación de un catéter venoso central (CVC) es una práctica común y necesaria en cuidados intensivos pediátricos. Sin embargo, dicho procedimiento no se encuentra carente de riesgos ni de complicaciones. Si bien clásicamente los CVC se han colocado siguiendo referencias anatómicas, el uso de la guía ecográfica ha reemplazado a este método, dado su mejor perfil de eficacia y seguridad, demostrado al menos en poblaciones adultas. Objetivos: Comparar la efectividad y seguridad en la inserción de catéteres venosos centrales femorales guiados por ecografía (US) versus mediante el método anatómico (LM) en pacientes críticos pediátricos. Métodos: Se aleatorizaron 100 pacientes: 50 se destinaron al grupo US y 49 al LM. En el grupo LM se usó el método tradicional palpando pulso femoral; en el grupo US se colocó el CVC guiado por ecografía en tiempo real. El éxito al primer intento, éxito global en la canulación, número de intentos y la punción arterial fueron las variables de estudio entre ambos grupos. Resultados: El éxito al primer intento y el éxito global en la canulación fueron significativamente mayores en el grupo US versus LM (US 42% vs. LM 18%, p=0,011; US 84% vs. LM 51%, p<0,001, respectivamente). La incidencia de punción de la arteria femoral fue menor en el grupo US (LM 12 vs. US 5, p=0,056) sin lograr significación estadística. Conclusiones: De acuerdo con nuestros resultados, la colocación del acceso venoso central por vía femoral debiera realizarse bajo guía ecográfica, aunque se necesitan estudios en poblaciones más numerosas que confirmen dichos resultados


Assuntos
Humanos , Criança , Cateterismo Venoso Central/métodos , Unidades de Terapia Intensiva Pediátrica , Resultado do Tratamento , Ultrassonografia , Artéria Femoral
4.
Med Intensiva (Engl Ed) ; 44(2): 96-100, 2020 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31630916

RESUMO

BACKGROUND: Central venous cannulation (CVC) is common and necessary in pediatric intensive care. However, this procedure is not without risks or complications. Although CVCs have classically been placed following anatomical landmarks, the use of ultrasound guidance has largely replaced the latter, given its better profile of efficacy and safety, demonstrated at least in adult populations. OBJECTIVES: To compare the effectiveness and safety in the insertion of femoral central venous catheters guided by ultrasound (US) versus the anatomical method (LM) in critical care pediatric patients. METHODS: 100 patients were randomized: 50 were assigned to the US group and 49 to the LM group. In the LM group the traditional method consisted in palpating the femoral artery pulse as a; in the US group the CVC was inserted using a real time technique. Success at the first attempt, overall success in cannulation, number of attempts and arterial puncture were the variables studied in both groups. RESULTS: Success at the first attempt and overall success in cannulation were significantly higher in the US group versus the LM (US 42% vs. LM 18%, p 0.011, US 84% vs. LM 51% p <0.001, respectively). The incidence of puncture of the femoral artery was lower in the US group (LM 12 vs. US 5, p 0.056) without achieving statistical significance. CONCLUSIONS: According to our results, the placement of central venous access via the femoral approach should be preferably performed under ultrasound guidance, however, further studies in larger populations are needed to confirm this findings.


Assuntos
Pontos de Referência Anatômicos , Cateterismo Venoso Central/métodos , Veia Femoral , Unidades de Terapia Intensiva Pediátrica , Ultrassonografia de Intervenção/métodos , Adolescente , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/estatística & dados numéricos , Criança , Pré-Escolar , Cuidados Críticos , Feminino , Artéria Femoral , Humanos , Lactente , Modelos Logísticos , Masculino , Palpação/métodos , Pulso Arterial , Punções/estatística & dados numéricos
5.
Mali méd. (En ligne) ; 35(35): 26-31, 2020. tab
Artigo em Francês | AIM (África) | ID: biblio-1265760

RESUMO

Introduction:L'hyperprolactinémie, qui est une sécrétion supra physiologique de prolactine est en clinique le désordre hypophysaire antérieur le plus fréquemment rencontré. Son incidence et sa prévalence sont peu définies, en Afrique et dans le reste du Monde.Les objectifs étaient d'étudier les aspects cliniques, paracliniques, étiologiques et thérapeutiques de l'hyperprolactinémie à l'hôpital du Mali.Méthodologie :Il s'agissait d'une étude transversale de 5 ans. La collecte des données a été rétrospective (juillet 2011 à octobre 2015) et prospective (décembre 2015 à juillet 2016).Résultats:Nous avons colligés 37 cas d'hyperprolactinémie. Le sex ratio était de 0,85. L'âge moyen était 37,32ans avec des extrêmes allant de 15 à 74 ans. Le tableau clinique était dominé chez les femmes par l'aménorrhée (80%), la galactorrhée (70%), les céphalées (55%), l'hypofertilité (50%), les troubles visuels (25%) et chez les hommes par la baisse de la libido (64,7%), la gynécomastie (47,1%), lescéphalées (47,1%), les troubles visuels (41,2%) et les troubles de l'érection (29,4%). La prolactinémie basale était supérieure à 100ng/mlchez 45,9% des patients. La tomodensitométrie cérébrale avait objectivé : 11 cas de macroadénomes et 5 cas demicroadénomes hypophysaires. Les principals causes de l'hyperprolactinémie étaient : l'adénome hypophysaire à prolactine (43,24%) ;l'hypothyroïdie(5,40%) et la prise d'oestroprogestatifs chez 5,40%. Pour le traitement, 64,9% des patients étaient mis sous cabergoline ; 27% sous bromocriptine et8,10% sous simple surveillance clinique et biologique.Conclusion:L'hyperprolactinémie est une pathologie qui existe dans nos structures de santé. Les cliniciens doivent y penser devant une aménorrhée galactorrhée ou une baisse de la libido. Il est aussi nécessaire d'améliorer le plateau technique pour une meilleure prise en charge


Assuntos
Diagnóstico , Hiperprolactinemia
6.
Int J Radiat Biol ; 94(11): 1062-1071, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30238840

RESUMO

PURPOSE: It is considered that exposure to static magnetic fields (SMF) may have both detrimental and therapeutic effect, but the mechanism of SMF influence on the living organisms is not well understood. Since the adenosine triphosphatases (ATPases) and acetylcholinesterase (AChE) are involved in both physiological and pathological processes, the modulation of Na+/K+-ATPase, ecto-ATPases and AChE activities, as well as oxidative stress responses were followed in synaptosomes isolated from rats after chronic exposure toward differently oriented SMF. MATERIAL AND METHODS: Wistar albino rats were randomly divided into three experimental groups (six animals per group): Up and Down group - exposed to upward and downward oriented SMF, respectively, and Control group. After 50 days, the rats were sacrificed, and synaptosomes were isolated from the whole rat brain and used for testing the enzyme activities and oxidative stress parameters. RESULTS: Chronic exposure to 1 mT SMF significantly increased ATPases, AChE activities, and malondialdehyde (MDA) level in both exposed groups, compared to control values. The significant decrease in synaptosomal catalase activity (1.48 ± 0.17 U/mg protein) induced by exposure to the downward oriented field, compared to those obtained for Control group (2.60 ± 0.29 U/mg protein), and Up group (2.72 ± 0.21 U/mg protein). CONCLUSIONS: It could be concluded that chronic exposure to differently oriented SMF increases ATPases and AChE activities in rat synaptosomes. Since brain ATPases and AChE have important roles in the pathogenesis of several neurological diseases, SMF influence on the activity of these enzymes may have potential therapeutic importance.


Assuntos
Acetilcolinesterase/metabolismo , Adenosina Trifosfatases/metabolismo , Campos Magnéticos/efeitos adversos , Sinaptossomos/enzimologia , Animais , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Sinaptossomos/metabolismo , Fatores de Tempo
7.
Int J Radiat Biol ; 93(5): 527-534, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28051886

RESUMO

PURPOSE: It has been shown that chronic exposure of young spontaneously hypertensive rats (SHR) to static magnetic field (SMF) delays the development of overt hypertension. Therefore the aim of the present work was to investigate the effects of SMF on autonomic cardiovascular control in adult spontaneously hypertensive rats. MATERIALS AND METHODS: Experiments were performed in freely moving spontaneously hypertensive rats equipped with femoral arterial catheter for blood pressure recording. Spontaneously hypertensive rats were exposed for 30 days to upward-oriented SMF (n = 17) or downward-oriented SMF (n = 17) of 16 mT intensity. A control group of spontaneously hypertensive rats (n = 17) was not exposed to SMF. Neurogenic cardiovascular control was evaluated by spectral analysis of arterial blood pressure and heart rate short-term variability and baro-receptor reflex sensitivity using the sequence method. RESULTS: Exposure of spontaneously hypertensive rats to both upward- and downward-oriented SMF significantly reduced arterial blood pressure and enhanced baro-receptor reflex sensitivity. Downward-oriented SMF reduced heart rate, too. SMF of either orientation reduced systolic blood pressure variability in very low frequency domain while downward-oriented SMF also reduced low-frequency and increased high frequency domains. CONCLUSION: It follows that prolonged exposure to SMF is beneficial for neurogenic cardiovascular control in hypertension.


Assuntos
Barorreflexo/efeitos da radiação , Pressão Sanguínea/efeitos da radiação , Frequência Cardíaca/efeitos da radiação , Hipertensão/fisiopatologia , Hipertensão/terapia , Magnetoterapia/métodos , Animais , Relação Dose-Resposta à Radiação , Campos Magnéticos , Masculino , Acoplamento Neurovascular/efeitos da radiação , Doses de Radiação , Ratos , Ratos Endogâmicos SHR , Resultado do Tratamento
8.
Int J Radiat Biol ; 92(3): 140-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26850041

RESUMO

PURPOSE: Static magnetic fields (SMF) have been widely used in research, medicine and industry. Since zinc and copper play an important role in biological systems, we studied the effects of the subchronic continuous SMF exposure on their distribution in murine tissues. MATERIALS AND METHODS: For 30 days, mice were exposed to inhomogeneous, vertical, downward or upward oriented SMF of 1 mT averaged intensity with spatial gradient in vertical direction. RESULTS: SMF decreased the amount of copper and zinc in liver. In brain, zinc levels were increased and copper levels were decreased. In spleen, zinc content was reduced, while copper amount remained unchanged. CONCLUSIONS: Subchronic exposure to SMF differently affected copper and zinc content in examined organs, and the changes were more pronounced for the downward oriented field. The outcome could be attributed to the protective, rather than the harmful effect of SMF.


Assuntos
Cobre/metabolismo , Campos Magnéticos , Vísceras/fisiologia , Vísceras/efeitos da radiação , Irradiação Corporal Total/métodos , Zinco/metabolismo , Animais , Relação Dose-Resposta à Radiação , Masculino , Camundongos , Especificidade de Órgãos/fisiologia , Especificidade de Órgãos/efeitos da radiação , Doses de Radiação , Distribuição Tecidual
9.
Environ Sci Pollut Res Int ; 23(2): 1584-97, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26377971

RESUMO

It has been shown that static magnetic field (SMF) of moderate intensity produces considerable impact on biological systems. SMF can be homogeneous or inhomogeneous. In many studies, inhomogeneous SMF was employed. Aware that inhomogeneous SMF could result in experimental variability, we investigated the influence of a vertical homogeneous SMF of different orientation. Male Swiss-Webster 9- to 10-week-old mice were subacutely exposed to upward- and downward-oriented SMF of 128 mT generated by a cyclotron for 1 h/day during a 5-day period. We found that SMF affected various organs and that these effects were, to some degree, dependent on SMF orientation. Both upward- and downward-oriented SMF caused a reduction in the amount of total white blood cells (WBC) and lymphocytes in serum, a decrease of granulocytes in the spleen, kidney inflammation, and an increase in the amount of high-density lipoprotein (HDL). In addition, upward-oriented SMF caused brain edema and increased spleen cellularity. In contrast, downward-oriented SMF induced liver inflammation and a decrease in the amount of serum granulocytes. These effects might represent a specific redistribution of pro-inflammatory cells in blood and among various organs. It appears that homogeneous SMF of 128 mT affected specific organs in the body, rather than simultaneously and equally influencing the entire body system.


Assuntos
Campos Magnéticos , Animais , Contagem de Eritrócitos , Contagem de Linfócitos , Linfócitos , Masculino , Camundongos , Baço
10.
Chemosphere ; 122: 288-294, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25532773

RESUMO

Trace elements accumulate in epidermis, liver, kidney and muscle tissues in cetaceans. However, contrarily to internal tissues, epidermis can be sampled using minimally-invasive techniques. We investigate the patterns of trace element tissue concentrations in relation to individual sex and length and the degree of inter-tissue equilibrium between epidermis and the main internal organs of the Mediterranean striped dolphin. With it, we aim to test whether epidermis is a suitable tissue to predict trace element concentrations of internal tissues in cetaceans. We focused on trace elements with high potential toxicity (mercury and cadmium) or biological significance (zinc, copper and selenium). In contrast to what was found for Cu and Zn, the concentrations of Hg, Cd and Se in epidermis were positively correlated with the levels found in the internal tissues sampled probably due to their capacity to bioaccumulate. Thus, we conclude that sampling and analysing epidermis is appropriate to monitor and predict the concentrations of Hg, Cd and Se in internal tissues but not for Cu and Zn.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Epiderme/metabolismo , Stenella/metabolismo , Oligoelementos/metabolismo , Análise de Variância , Animais , Feminino , Masculino , Especificidade de Órgãos
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