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1.
Acta toxicol. argent ; 26(1): 1-11, mayo 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-973611

RESUMO

El hombre ha cambiado el ambiente para sostener la demanda global de recursos naturales como el agua. La gestión de los cuerpos hídricos tiene que ser constante, con el propósito preventivo y correctivo, dependiendo del estado de antropización de cada sistema. El objetivo de este artículo fue analizar la toxicidad del sedimento y los metales Mn, Zn, Pb, Ni, Cd y Cu, en el reservorio Paiva Castro, que abastece la Region Metropolitana de São Paulo. Se realizaron 2 muestreos (Mayo 2011, estación seca y Enero de 2012, estación húmeda) y se analizaron 5 puntos próximos a la captación de agua por la Companhia de Saneamento Básico do Estado de São Paulo. Se realizaron ensayos de toxicidad aguda y crónica en sedimento, a través de ensayos biológicos con el cladócero Daphnia similis y el insecto Chironomus xanthus. El tratamiento de datos se realizó con el test de Fisher (mortalidad). El nivel de asociación entre las variables en sedimento y en los test ecotoxicológicos fueron evaluados por test no-paramétricos, a través del coeficiente de correlación de Spearman's. Los resultados del presente trabajo señalaron bajas concentracones de metales en el sedimento del área de estudio y ausencia de toxicidad en los organismos ensayados. Se puede concluir que área estudiada del reservorio Paiva Castro se encuentra poco impactada por los metales, sin efectos directos sobre la calidad de vida los organismos bentónicos: D. similis y C. xanthus.


Man had changed the natural environment in an attempt trying to supply the global demand for resources. The management of the hydric bodies has to be constant, with preventive and corrective purpose, depending on the eutrophization state of each one. The objective of this article was to analyze the sediment toxicity and the metals Mn, Zn, Pb, Ni, Cd and Cu, in the Paiva Castro reservoir, that supply the Metropolitan Region of São Paulo. It was made 2 collections (May 2011, dry season and January 2012, wet season). It was analyzed 5 points next to the water captation station by the Companhia de Saneamento Básico do Estado de São Paulo. The sediment was analyzed as for acute and chronic toxicity through bioassays with the cladocerans Daphnia similis and the insect Chironomus xanthus. Data treatment was done with Fisher Exact Test (mortality). The association level between the variables in sediment and ecotoxicological tests was available in non-parametric tests, through the Spearman's correlation coefficient. Oriented on the results presented in this work, pointing low concentrations of heavy metals in the sediments presented in the collect local, and the absence of toxicity, we can say that at this reservoir, at least in the collect area, it's low impacted, not implicating in direct interferences in the quality of life of benthonic organisms.


Assuntos
Zinco/toxicidade , Cádmio/toxicidade , Reservatórios de Água/prevenção & controle , Sedimentos/análise , Cobre/toxicidade , Chumbo/toxicidade , Manganês/toxicidade , Níquel/toxicidade , Brasil , Metais Pesados/toxicidade , Testes de Toxicidade Aguda/análise , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/análise , Testes de Toxicidade Crônica/métodos
2.
An. Fac. Cienc. Méd. (Asunción) ; 50(1): 51-60, ene-abr. 2017.
Artigo em Espanhol | LILACS | ID: biblio-884475

RESUMO

Introducción: El presente estudio describe los patrones de natriuresis según las características clínicas y sociodemográficas en una población adulta de Asunción. Métodos: Estudio transversal tipo encuesta y toma de muestra de orina a personas que acudieron al Mercado de Abasto y al Policlínico Municipal durante los meses de junio-setiembre del 2014. Se estimó natriuria en muestras de orina espontánea a primera hora de la mañana y en ayunas. Se incluyeron sujetos de 18 a 65 años. Se compararon las medianas de los valores de natriuria en mmol/L, utilizándose el test U de Mann-Whitney para comparar las variables de dos categorías y Kruskal-Wallis para las que tienen más de dos categorías. Resultados: Se aplicó la encuesta y se tomó muestra de orina a 463 personas. El 69,5% (322) eran mujeres. La media de edad fue 50,5 años (DE: 14,2). El 26,6% (123) negó antecedentes patológicos. La mediana de natriuria global fue 97,5 mmol/L (RIC: 59,3­139,3). Los niveles de natriuria no presentaron diferencias por sexo. Las personas menores de 30 años, con bajo consumo de verduras y mayor consumo de frituras presentaron valores de natriuria altos y estadísticamente significativos. El grupo de sujetos sanos mostró mayor excreción de sodio que los que refirieron diabetes o hipertensión arterial. Conclusiones: La mayor excreción de sodio en orina observada se presenta en personas jóvenes, sin antecedentes patológicos y, al mismo tiempo son los que también presentan los peores hábitos alimenticios. Estos resultados muestran la necesidad de intervención en el ámbito de la salud pública a fin de prevenir la patología cardiovascular y renal del futuro.


Introduction: The present study describes natriuresis patterns according to clinical and sociodemographic characteristics in adult population of Asuncion. Methods: Cross-sectional study of convenience sampling to people who attended the Mercado de Abasto and the Municipal Polyclinic during June to September 2014. People from 18 to 65 years old were included. Sodium was estimated from urine samples of spot urine taken in the morning and fasting. Median values of natriuresis in mmol/L were compared using the test Mann-Whitney and Kruskal-Wallis. Results: 463 people participated. 69.5% (322) were women. The mean age was 50.5 years (SD 14.2). 26.6% (123) denied pathological medical history. The median overall natriuresis was 97.5 mmol/L (IQR: 59.3-139.3). Natriuresis levels did not differ by sex. High values with statistically significant were presented in people under 30 years old, with low consumption of vegetables and increased consumption of fried food. The group of healthy subjects showed increased sodium excretion than those who reported diabetes or high blood pressure. Conclusions: The increased natriuresis occurs in young people without having pathological medical history and also having the worst eating habits. Public health policies must focus at this level to prevent future cardiovascular and renal disease it is at this level where public health must intervene to prevent future cardiovascular and renal disease.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Sódio na Dieta/efeitos adversos , Natriurese , Estudos Transversais , Dieta Hipossódica , Hipertensão/etiologia
3.
An. Fac. Cienc. Méd. (Asunción) ; 49(2): 17-26, jul-dic. 2016.
Artigo em Espanhol | LILACS | ID: biblio-884936

RESUMO

Introducción: Paraguay no escapa a la epidemia global de obesidad. Este estudio describió la prevalencia y los determinantes sociodemográficos, clínicos y conductuales asociados en el país. Métodos: Estudio transversal tipo encuesta poblacional con representatividad nacional, incluyó personas entre edades de 15 y 74 años. El muestreo fue probabilístico, trietápico sin reemplazo. STEPSwise fue la metodología y encuesta aplicada durante junio-setiembre 2011. Se consideró obesidad un índice de masa (IMC) corporal >=30. Este valor se distribuyó según las variables sociodemográficas, clínicas y conductuales. Por regresión logística se estimó asociación entre las variables, en odd ratios (OR) con intervalos de confianza del 95%(IC95%). Resultados: Se incluyeron 2501 participantes. Fueron obesos 23,5% de la población, 20,2% y 26,0% hombres y mujeres, respectivamente. Además del sexo, mostraron diferencias significativas: tener >35 años 3,17(2,11-4,76) que los menores; hombres con residencia urbana 1,94(1,35-2,79) veces más que los del área rural. Los hombres en pareja 2,52(1,80-3,53) veces más obesos que los solteros; funcionario público 2,57(1,57-4,26) veces más que otros trabajos. Baja actividad física presentó obesidad 1,75(1,19-2,57) veces más que tener una actividad física mínimamente aceptable. En hombres el quintil de ingreso superior presentó 3,87(2,17-6,92) más obesidad que el quintil inferior. En mujeres el bajo nivel educativo es 2,01(1,43-2,83) veces más que un mayor nivel. Conclusiones: El patrón observado de la distribución de la obesidad describe entornos y conductas más obesogénicos que otros en Paraguay. Estos resultados sirven para tomar decisiones e intervenciones específicas en salud pública, más allá de las medidas poblacionales.


Introduction: Paraguay has not escaped from the global epidemic of obesity. This study described the prevalence and socio-demographic, clinical and behavioral determinants associated to obesity. Methods: Cross-sectional study with a nationally representative survey, included people among 15 and 74 years old. The sampling was probabilistic, three-stage without replacement. STEPSwise was the methodology and survey applied during June-September 2011. Obesity was considered a body mass index (BMI) >=30 kg/m2. This value was distributed by sociodemographic, clinical, and behavioral variables. A logistic regression among obesity and variables was estimated for obtain odd ratios (OR) with confidence intervals of 95% (95% CI) of association. Results: 2501 participants were included. Were obese 23.5%, men and women were 20.2% and 26.0%, respectively. In addition to gender, showed significant differences: >35 years-old 3.17(2.11-4.76) than younger; men in urban residence 1.94(1.35-2.79) odds more than those in rural areas. No single men 2.52(1.80-3.53) odds more obese than single; civil servants 2.57(1.57-4.26) odds more than other jobs. Low physical activity 1.75(1.19-2.57) odds were more obese than a acceptable physical activity. In mans with the top income quintile showed 3.87(2.17-6.92) more obesity than the bottom quintile. In women, low educational level was 2.01(1.43-2.83) odds more than a higher. Conclusions: The observed pattern of obesity distribution in Paraguay described some behaviors and obesogenic environments. These results serve to take decisions and specific interventions in public health, beyond the population measures.

4.
Braz. j. med. biol. res ; 42(9): 844-853, Sept. 2009. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-524316

RESUMO

Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR) and normotensive control rat strains (WKY and NWR). Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.


Assuntos
Animais , Masculino , Ratos , Aorta/química , Membrana Celular/química , Colesterol/análise , Hipertensão/metabolismo , Artérias Mesentéricas/química , Fosfolipídeos/análise , Colesterol/química , Espectroscopia de Ressonância de Spin Eletrônica , Cromatografia Gasosa-Espectrometria de Massas , Hipertensão/etiologia , Músculo Liso Vascular/química , Músculo Liso Vascular/citologia , Fosfolipídeos/química , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
5.
Braz. j. biol ; 64(3a): 465-478, ago. 2004. ilus, mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-393490

RESUMO

Foram encontradas 34 espécies de protistas ciliados nas amostras coletadas nas margens da lagoa de Cabiúnas em 2001. Os ciliados foram cultivados em laboratório, onde foram examinados in vivo e identificados por meio de técnicas de impregnação pela prata. Uma nova espécie, Oxytricha marcili (Ciliophora, Oxytrichidae), foi encontrada e caracterizada. Mede, in vivo, aproximadamente 60-80 mm de comprimento por 30-40 mm de largura. Apresenta em média 22 membranelas adorais, 18 cirros marginais esquerdos, 18 cirros marginais direitos e 3 cirros caudais de dimensões reduzidas. Todos os espécimes analisados apresentam 7 cirros frontais (3 anteriores + 4 posteriores), 1 cirro bucal, 4 cirros ventrais (3 pós-orais + 1 pré-transverso) e 5 cirros transversos. Dentre as espécies identificadas, algumas são consideradas indicadoras de qualidades de água que variam de alfa-mesossaprobidade a polissaprobidade e isossaprobidade.


Assuntos
Animais , Monitoramento Ambiental , Água Doce , Biodiversidade , Brasil , Microscopia Eletrônica de Varredura , Oxytricha/ultraestrutura
6.
Braz. j. biol ; 64(3)2004.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467717

RESUMO

We found 34 species of ciliate protists in the samples collected by the margins of Cabiúnas Lagoon during 2001. The ciliates were cultivated in the laboratory, where they were examined in vivo and identified through silver impregnation techniques. A new species, Oxytricha marcili (Ciliophora, Oxytrichidae), was found and characterized as follows: in vivo length about 60-80 mum x 30-40 mum wide; on average 22 adoral membranelles; 18 left marginal cirri; 18 right marginal cirri; and 3 small caudal cirri. All specimens analyzed presented 7 frontal cirri (3 anterior + 4 posterior), 1 buccal cirrus, 4 ventral cirri (3 postoral + 1 pre-transverse), and 5 transverse cirri. Among the species found, some are considered as water quality indicators ranging from alpha-mesosaprobity to polysaprobity and isosaprobity.


Foram encontradas 34 espécies de protistas ciliados nas amostras coletadas nas margens da lagoa de Cabiúnas em 2001. Os ciliados foram cultivados em laboratório, onde foram examinados in vivo e identificados por meio de técnicas de impregnação pela prata. Uma nova espécie, Oxytricha marcili (Ciliophora, Oxytrichidae), foi encontrada e caracterizada. Mede, in vivo, aproximadamente 60-80 mim de comprimento por 30-40 mim de largura. Apresenta em média 22 membranelas adorais, 18 cirros marginais esquerdos, 18 cirros marginais direitos e 3 cirros caudais de dimensões reduzidas. Todos os espécimes analisados apresentam 7 cirros frontais (3 anteriores + 4 posteriores), 1 cirro bucal, 4 cirros ventrais (3 pós-orais + 1 pré-transverso) e 5 cirros transversos. Dentre as espécies identificadas, algumas são consideradas indicadoras de qualidades de água que variam de alfa-mesossaprobidade a polissaprobidade e isossaprobidade.

7.
Braz. j. med. biol. res ; 33(8): 919-27, Aug. 2000. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-265849

RESUMO

Hypertension is one of the major precursors of atherosclerotic vascular disease, and vascular smooth muscle abnormal cell replication is a key feature of plaque formation. The present study was conducted to examine the relationship between hypertension and smooth muscle cell proliferation after balloon injury and to correlate neointima formation with resting membrane potential of uninjured smooth muscle cells, since it has been suggested that altered vascular function in hypertension may be related to the resetting of the resting membrane potential in spontaneously hypertensive rats (SHR). Neointima formation was induced by balloon injury to the carotid arteries of SHR and renovascular hypertensive rats (1K-1C), as well as in their normotensive controls, i.e., Wistar Kyoto (WKY) and normal Wistar (NWR) rats. After 14 days the animals were killed and the carotid arteries were submitted to histomorphometric and immunohistochemical analyses. Resting membrane potential measurements showed that uninjured carotid arteries from SHR smooth muscle cells were significantly depolarized (-46.5 + or - 1.9 mV) compared to NWR (-69 + or - 1.4 mV), NWR 1K-1C (-60.8 + or - 1.6 mV), WKY (-67.1 + or - 3.2 mV) and WKY 1K-1C (-56.9 + or - 1.2 mV). The SHR arteries responded to balloon injury with an enhanced neointima formation (neo/media = 3.97 + or - 0.86) when compared to arteries of all the other groups (NWR 0.93 + or - 0.65, NWR 1K-1C 1.24 + or - 0.45, WKY 1.22 + or - 0.32, WKY 1K-1C 1.15 + or - 0.74). Our results indicate that the increased fibroproliferative response observed in SHR is not related to the hypertensive state but could be associated with the resetting of the carotid smooth muscle cell resting membrane potential to a more depolarized state


Assuntos
Animais , Ratos , Angioplastia com Balão/efeitos adversos , Lesões das Artérias Carótidas/patologia , Hipertensão Renovascular/complicações , Músculo Liso Vascular/patologia , Análise de Variância , Lesões das Artérias Carótidas/etiologia , Estudos de Casos e Controles , Contagem de Células , Modelos Animais de Doenças , Potenciais da Membrana , Ratos Endogâmicos WKY , Ratos Wistar , Túnica Íntima/patologia
8.
Arq. bras. med. vet. zootec ; 52(4): 350-3, ago. 2000. tab
Artigo em Português | LILACS | ID: lil-273621

RESUMO

The objective of this work was to identify flies of medical and veterinary importance and their natural enemies, located around the city of Itumbiara, GO, Brazil. Five thousand eight hundred and twenty-five muscoid dipterous insects and parasitoids were collected from a Brazilian savanna (cerrado) area of Itumbiara. Substrates for obtaining flies were liver. The most frequent fly and parasitoid species found were: Fannnia pusio (29.2 per cent) and Atherigona orientalis (26.8 per cent) (flies), Nasonia vitripennis (56.0 per cent) and Brachymeria sp. (26.6 per cent) (parasitoids). Musca domestica was the dipterous species of greatest sanitary importance collected. This is the first report of the species Brachymeria sp. and Hememcyrtus sp. in the State of Goias. Data contribute to the knowledge of dipterous and parasitoids fauna in the state of Goias


Assuntos
Dípteros/parasitologia
9.
Braz. j. med. biol. res ; 27(8): 1911-6, Aug. 1994. graf
Artigo em Inglês | LILACS | ID: lil-143627

RESUMO

The increase in sensitivity of guinea pig preparations to bradykinin (BK) due to stretching occurring with time after mounting was studied by determining the time course of changes in the cell membrane potential, measured with intracellular microelectrodes. A sustained hyperpolarizing effect of BK, which was observed in recently mounted preparations, became transient after 120 min, when it was followed by depolarization, which was much more evident after 4 h of stretching. As a consequence, a parallel increase in the contractile response to BK was also observed. The hyperpolarizing effect was due to the opening of Ca²+-dependent K+ channels sensitive to apamin, since BK dose-response curves done within 1 h of mouting were shifted to the left, becoming similar to dose-response curves obtained 4 h after mounting of the guinea pig ileum preparation. These results were specific for BK, since the potentiating effect of apaming was not observed for acetylcholine. Our results show that the activation of B2 receptors by BK in the isolated guinea pig ileum induce a dual effect - hyperpolarization and depolarization - and that the increase in the contractile response consequent to stretching is probably due to the inactivation of apaminsensitive Ca²+-dependent K+ channels


Assuntos
Cobaias , Animais , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Receptores da Bradicinina/fisiologia , Apamina/farmacologia , Bradicinina/farmacologia , Canais de Cálcio , Canais de Cálcio/fisiologia , Canais de Potássio , Canais de Potássio/fisiologia , Contração Muscular , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Relaxamento Muscular/efeitos dos fármacos , Relaxamento Muscular/fisiologia , Músculo Liso , Receptores da Bradicinina/efeitos dos fármacos
10.
Braz. j. med. biol. res ; 22(9): 1137-40, 1989. ilus
Artigo em Inglês | LILACS | ID: lil-83190

RESUMO

The response of the rat duodenum to bradykinin (BK) consists of relaxant and contractile components, which have been atributed to different receptor types. To characterize the receptor responsible for this diphasic response we studied the effects of BK analogues known to act on B1 or B2 receptors in other systems. DesArg**9-Leu**8-BK and Thi**5,**8DPhe**7-BK presented only relaxant and only contractile effects, respectively, whereas DArgOHyp883Thi**5,**8DPhe**7-BK was a potent antagonist of the relaxation (but not of the contraction) induced by BK. Our results show that the relaxant and contractile components of the rat duodenum's response to BK are due to B2 and B1 receptor subtypes, respectively


Assuntos
Ratos , Animais , Feminino , Bradicinina/farmacologia , Duodeno/metabolismo , Receptores de Neurotransmissores/metabolismo , Sequência de Aminoácidos , Bradicinina/análogos & derivados , Bradicinina/metabolismo , Contração Muscular , Relaxamento Muscular/efeitos dos fármacos
11.
Braz. j. med. biol. res ; 22(9): 1145-9, 1989. tab, ilus
Artigo em Inglês | LILACS | ID: lil-83192

RESUMO

The development of tachyphylaxis to [1-sarcosine]-angiotensin II was studied in helical strips and everted rings of rabbit aorta. Strips, but not everted rings, developed marked (>50%) tachyphylaxis to the peptide, when challenged repeatedly at 1-h intervals. Measurements of the membrane potential showed no difference between the two preparations, but strips were more sensitive to KC1 than everted rings. These results suggest that the strips are more depolarized than the everted rings due to lesions caused by the spiral cutting. This partial depolarization may underlie the tachyphylactic phenomenon


Assuntos
Coelhos , Animais , Masculino , Feminino , Angiotensina II/análogos & derivados , Aorta Torácica/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Taquifilaxia , Músculo Liso Vascular
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