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1.
Reprod Domest Anim ; 52(5): 836-841, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28580754

RESUMEN

The goal of this study was to determine the distribution of pre-antral follicles in the ovarian parenchyma of mares. For Experiment 1, each ovary was cut longitudinally at the greater curvature, performing two hemiovaries. After that, six fragments from each hemiovary were obtained, resulting in 12 fragments, which were divided into the innermost region of the parenchyma, the middle region and the outermost region. All the three obtained sections were cut transversally to obtain two fragments from each one. For Experiment 2, each ovary also submitted to a longitudinal cut on the greater curvature, forming two hemiovaries. Each hemiovary was sectioned into four symmetrical fragments, resulting in eight fragments per ovary. The fragments were related as being near to or far from the ovulatory fossa. The fragments of both experiments were immediately fixed in Carnoy for 12 hr and kept in 70% ethanol for 24 hr. Follicles were classified according to the stages of development and for morphological integrity according to oocyte morphology and granulosa cells. After the histological assessment, a total of 1,130 follicles were visualized from Experiment 1, being 1,054 (93.3%) primordial follicles and 76 (4.7%) follicles in development. The innermost region had the highest percentage of pre-antral follicles compared to the other regions (p < .05). The middle and outermost regions showed higher percentages of intact primordial and developing follicles than the innermost region (p < .05). Considering Experiment 2, 938 follicles were found, being 894 (95.3%) primordial and 44 (4.7%) follicles in development. The region near the ovulatory fossa presented higher (58.7%; 551 of 938) follicular concentration compared to the region far from the ovulatory fossa (41.3%; 387 of 938; p < .05). As a conclusion, distribution of pre-antral follicles in the equine ovary has a specific pattern through the parenchyma. Also, the follicular integrity differed in the studied ovarian areas.


Asunto(s)
Caballos , Folículo Ovárico/anatomía & histología , Ovario/anatomía & histología , Animales , Femenino , Células de la Granulosa , Oocitos , Folículo Ovárico/fisiología
2.
Phytother Res ; 30(1): 49-57, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26514663

RESUMEN

Hypercholesterolemia is a metabolic disorder characterized by high levels of low-density lipoprotein and blood cholesterol, causing inflammatory lesion. Purinergic signaling modulates the inflammatory and immune responses through adenine nucleotides and nucleoside. Guaraná has hypocholesterolemic and antiinflammatory properties. Considering that there are few studies demonstrating the effects of guaraná powder on the metabolism of adenine nucleotides, we investigated its effects on the activity of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) and ecto-adenosine deaminase activity in lymphocytes of rats with diet-induced hypercholesterolemia. The rats were divided into hypercholesterolemic and normal diet groups. Each group was subdivided by treatment: saline, guaraná powder 12.5, 25, or 50 mg/kg/day and caffeine concentration equivalent to highest dose of guaraná, fed orally for 30 days. An increase in adenosine triphosphate hydrolysis was observed in the lymphocytes of rats with hypercholesterolemia and treated with 25 or 50 mg/kg/day when compared with the other groups. The hypercholesterolemic group treated with the highest concentration of guaraná powder showed decreased ecto-adenosine deaminase activity compared with the normal diet groups. Guaraná was able to reduce the total cholesterol and low-density lipoprotein cholesterol to basal levels in hypercholesterolemic rats. High concentrations of guaraná associated with a hypercholesterolemic diet are likely to have contributed to the reduction of the inflammatory process.


Asunto(s)
Cafeína/farmacología , Hipercolesterolemia/tratamiento farmacológico , Paullinia/química , Teobromina/farmacología , Teofilina/farmacología , Adenosina Desaminasa/metabolismo , Animales , Colesterol/sangre , LDL-Colesterol/sangre , Dieta Alta en Grasa , Linfocitos/enzimología , Masculino , Preparaciones de Plantas/farmacología , Ratas , Ratas Wistar
3.
Ann Trop Med Parasitol ; 105(5): 385-91, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21929880

RESUMEN

This study aimed to evaluate the activity of cholinesterases and adenosine deaminase (ADA) in blood and serum of rats infected with Trypanosoma cruzi. Twelve adult rats were used in the experiment divided into two uniform groups. Rodents from group A (control group) were non-infected and animals from group B served as infected, receiving intraperitoneally 3·3×10(7) trypomastigotes/each. Blood collection was performed at days 60 and 120 post-infection (PI) in order to evaluate the hemogram, blood activity of acetylcholinesterase, and serum butyrylcholinesterase and ADA activities. Hematological parameters did not differ between groups. A significant increase (P<0·05) of acetylcholinesterase activity was observed in blood while butyrylcholinesterase had a significant reduction (P<0·01) in serum of infected rats at days 60 and 120 PI. ADA activity in serum showed an inhibition in infected animals when compared to non-infected at day 120 PI. Based on these results, it is possible to conclude that the activity of cholinesterases and ADA were changed in animals infected with T. cruzi. The possible causes of these alterations will be discussed in this paper.


Asunto(s)
Adenosina Desaminasa/sangre , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/inmunología , Enfermedad de Chagas/inmunología , Colinesterasas/sangre , Corazón/parasitología , Trypanosoma cruzi/patogenicidad , Animales , Enfermedad de Chagas/enzimología , Masculino , Actividad Motora , Ratas
4.
Rev Saude Publica ; 30(6): 609-16, 1996 Dec.
Artículo en Portugués | MEDLINE | ID: mdl-9302832

RESUMEN

Schistosomiasis mansoni can be considered an important public health problem in Northeastern Brazil, in spite of the reduction in the prevalence of the hepatosplenic clinical forms which have been attributed to the large scale use of chemotherapy in this country. However, the rise in the prevalence rates and the spread of this endemic disease to new areas show that schistosomiasis is assuming its must cruel expression: less lethal but more greatly incapacitating in terms of irreversible physical and moral damage to human beings. The state of Pernambuco presents growing rates for schistosomiasis infection in humans. The epidemiological profile of this disease displays high and consistent prevalence rates (up to 80%) in rural areas, and new cases of acute infection on the coast, where schistosomiasis has recently been introduced. The reproduction and expansion of this endemic disease can be better understood on the basic of a conception of structural and historical causation. The disease construction process should be reconstructed in the light of biological as well as the social, political and cultural factors which are jointly responsible for the present endemic situation. Within that frame work, the historical and socioeconomic features that interact with the parasite and give rise to the present proportions of the schistosomiasis epidemic in Pernambuco are discussed. The mode of occupation and use of the land, unemployment, under-nutrition, migration, etc., raise the question of the growing difficulties confronting the control of the disease, both in rural areas where populations are extremely mobile as well as in the poorly organized urban population. Epidemiological investigation is fulfilling its role in its attempts to understand the complex relationships of an intrinsecally social nature of the health/disease process between health problems and the quality of life for the purpose of producing consistent disease control models.


Asunto(s)
Esquistosomiasis mansoni/epidemiología , Brasil/epidemiología , Carencia Cultural , Enfermedades Endémicas , Humanos , Prevalencia , Esquistosomiasis mansoni/prevención & control , Factores Socioeconómicos , Urbanización
5.
Rev Saude Publica ; 34(4): 337-41, 2000 Aug.
Artículo en Portugués | MEDLINE | ID: mdl-10973151

RESUMEN

INTRODUCTION: In 1988, 22 autochthonous cases from accidental exposure were registered in Forte Orange beach, Itamaracá Island, Pernambuco, Brazil. All cases occurred in middle-to-upper class individuals who were vacationing in the island. After the cases were identified, the major objective was to find breeding sites of schistosomiasis vectors and correlate the biological factors with the environmental conditions. METHODS: The environmental characteristics of the beach before human occupation were obtained from several documents. Also, a one-year malacological survey was conducted with monthly collection of mollusks, and the determination of their infectivity rates. RESULTS/CONCLUSIONS: The malacological survey was able to identify 20 breeding sites of Biomphalaria glabrata and 28 capture station were set up. Snails were collected and examined each month throughout a whole year. The results show a seasonal variation in the mollusk population density associated with infection rates and types of breeding sites. The importance of this new epidemiological profile of schistosomiasis in the State of Pernambuco relies on the fact that it can be related with the drastic human interference on the environment. Ecological, environmental, and demographic factors as well as the epidemiological characteristics of the disease have social and economic repercussions.


Asunto(s)
Reservorios de Enfermedades , Vectores de Enfermedades , Ecosistema , Esquistosomiasis mansoni/epidemiología , Animales , Biomphalaria/parasitología , Brasil/epidemiología , Clima , Enfermedades Endémicas , Factores Epidemiológicos , Humanos , Moluscos/fisiología , Densidad de Población , Schistosoma mansoni/parasitología , Estaciones del Año , Salud Urbana
6.
Percept Mot Skills ; 56(1): 135-8, 1983 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6844062

RESUMEN

Judged distance in a large open field, scaled by the method of magnitude estimation, is related to physical distance by a power function with an exponent smaller than unity. The exponents obtained with two ranges of distance were not affected by the availability of a standard. The mean exponent for all 80 individual power functions was 0.86, with a standard deviation of 0.11.


Asunto(s)
Percepción de Distancia , Adolescente , Adulto , Señales (Psicología) , Humanos , Psicofísica
7.
Artículo en Inglés | MEDLINE | ID: mdl-25215816

RESUMEN

It is shown in direct numerical simulations of homogeneous isotropic non-stationary turbulence that there is a systematic and significant imbalance between the non-linear energy cascade to fine scales and its dissipation. This imbalance stems from the power required to induce or annihilate fine-scale motions in order to change the level of dissipation. The imbalance is present regardless of transfer time-lags and is applicable to a wide range of Reynolds numbers.


Asunto(s)
Simulación por Computador , Modelos Teóricos , Movimiento (Física) , Dinámicas no Lineales
9.
Philos Trans A Math Phys Eng Sci ; 369(1937): 811-32, 2011 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-21242135

RESUMEN

A Euromech colloquium, on interfacial processes and inhomogeneous turbulence, was held in London on 28-30 June 2010. Papers were presented describing and analysing the influence of interfaces that separate turbulent/non-turbulent regions, between regions of contrasting fluid properties, or at the edge of boundaries. This paper describes a summary of the work presented, giving a snapshot of the current progress in this area, along with discussions about future research directions.

10.
Rev. bras. plantas med ; Rev. bras. plantas med;18(1,supl.1): 349-355, 2016. graf
Artículo en Portugués | LILACS | ID: lil-782971

RESUMEN

RESUMO Aleloquímicos são substâncias liberadas por certas espécies vegetais no ambiente que influenciam a germinação e o desenvolvimento de outras plantas. O objetivo desse estudo foi avaliar o potencial fitotóxico de Cleome guianensis Aubl., bem como determinar o grau de estresse oxidativo causado em Senna occidentalis L. Para isso, o óleo das folhas de C. guianensis, nas concentrações 0,5 µg/mL, 1,0 µg/mL, 2,5 µg/mL e 5,0 µg/mL, em solução de 5 ml foi testado em bioensaios de germinação e de crescimento da raiz primária e do hipocótilo de S. occidentalis. Os indivíduos de S. occidentalis foram macerados, homogeneizados e submetidos a ensaios de quantificação da catalase, peroxidase, SOD e de peroxidação lipídica. Os resultados indicam que todas as concentrações do óleo volátil causaram um efeito negativo sobre a germinação e crescimento de S. occidentalis. Na concentração 5,0 µg/mL, houve 56% de inibição da germinação e 83% de inibição de crescimento do hipocótilo. Ainda, o óleo aumentou a atividade das enzimas induzidas pelo estresse oxidativo catalase, peroxidase e superóxido dismutase (SOD). Quanto à peroxidação lipídica, o óleo nas concentrações 1,0 µg/mL, 2,5 µg/mL e 5,0 µg/mL aumentou a produção de malondialdeído. Sendo assim, conclui-se que C. guianensis apresenta aleloquímicos que influenciam na germinação e no crescimento de S. occidentalis, além de aumentar a atividade das enzimas catalase, peroxidase, SOD e a produção de malondialdeído em S. occidentalis. Dessa forma, sugere-se a realização de estudos sobre o perfil químico do óleo a fim de descobrir as substâncias responsáveis por tais resultados e consolidar o potencial fitotóxico de C. guianensis.


ABSTRACT Allelochemicals inhibit the germination and growth of other plants. The purpose of this study was to assess the phytotoxic potential of Cleome guianensis Aubl., as well as determine the degree of oxidative stress caused in Senna occidentalis L. For this purpose, oil from the leaves of C. guianensis in concentrations of 0.5 µg/mL, 1.0 µg/mL, 2.5 µg/mL, and 5.0 µg/mL were tested in bioassays on the germination and growth of S. occidentalis. Specimens of S. occidentalis were macerated, homogenized, and submitted to catalase, peroxidase, superoxide dismutase (SOD), and lipid peroxidation quantification tests. Results showed that all concentrations of the volatile oil had a negative effect on S. occidentalis germination and growth. In the 5.0 µg/mL concentration, the oil inhibited 56% of germination and 83% of hypocotyl growth. In addition, the oil increased the activity of the enzymes induced by oxidative stress: catalase, peroxidase, and superoxide dismutase SOD. For lipid peroxidation, the oil in the 1.0 µg/mL, 2.5 µg/mL and 5.0 µg/mL concentrations increased the production of malondialdehyde. In addition, C. guianensis presents allelochemicals that influence the germination and growth of S. occidentalis, also enhancing activity of the catalase, peroxidase, and SOD enxymes, as well as malondialdehyde production in S. occidentallis. Hence, further studies of the chemical profile of this oil should be performed in order to discover which allelochemicals are responsible for these results and consolidate the phytotoxic potential of C. guianensis.


Asunto(s)
Senna/clasificación , Cleome/química , Alelopatía , Estrés Oxidativo
11.
Res Vet Sci ; 91(2): 240-2, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21185577

RESUMEN

Trypanosoma evansi infections in domestic animals are characterized by anemia and thrombocytopenia. The cause of the platelets decrease is unknown, but researchers suggest that thrombocytopenia may result from damage of the bone marrow, reduced survival of platelets, auto-immune thrombocytopenia, disseminated intravascular coagulation and splenic sequestration. Some of these causes have already been tested by our research group and found to be unrelated. Therefore, this study has the objective of testing the hypothesis that splenic sequestration might be responsible for thrombocytopenia in T. evansi-infected rats. A total of 28 rats assigned to four groups were used in the experiment. Group A rats were splenectomized and infected with T. evansi, group B rats were infected with T. evansi, group C rats were splenectomized, but not infected and group D rats were normal controls. Five days post-infection all rats were anesthetized and blood was collected in order to measure the number of circulating platelets, fibrinogen levels, prothrombin time (PT) and activated partial thromboplastin time (aPTT). The spleens of groups B and D were weighed at necropsy. The infected animals (groups A and B) showed a significant reduction in platelets and increased PT and aPTT when compared to negative control groups (groups C and D). Animals from group A showed increased levels of fibrinogen. The mean weight of spleen differed between group B (2.62g) and group D (0.55g). It was concluded that there is no relationship between thrombocytopenia and splenic sequestration in infection by T. evansi.


Asunto(s)
Hiperesplenismo/etiología , Enfermedades de los Roedores/etiología , Bazo/patología , Trombocitopenia/etiología , Tripanosomiasis/complicaciones , Animales , Femenino , Fibrinógeno/análisis , Hiperesplenismo/sangre , Hiperesplenismo/patología , Recuento de Plaquetas/veterinaria , Protrombina/análisis , Ratas , Enfermedades de los Roedores/sangre , Enfermedades de los Roedores/patología , Esplenectomía/veterinaria , Trombocitopenia/sangre , Trombocitopenia/patología , Tromboplastina/análisis , Trypanosoma/fisiología , Tripanosomiasis/sangre , Tripanosomiasis/patología
12.
Pak J Biol Sci ; 12(24): 1581-4, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-20334120

RESUMEN

Aloysia gratissima is used in Brazilian folk medicine for the treatment of digestive and respiratory diseases. The infusions (6 and 24 g L-1) and essential oils (0.25%, on ethanol) were prepared and we used groups of five Allium cepa bulbs for each treatment. A total of 2500 cells per treatment were analyzed and the mitotic indexes were calculated. The antiproliferative effect of infusions and essential oils of Aloysia gratissima on the Allium cepa (onion) cell cycle was evaluated using the leaves of studied specimens. The infusions presented a significant decrease in the mitotic index (4.55% at 6 g L-1 and 2.04% at 24 g L-1) compared to the control-water (6.83%), as well as for the essential oil (2.58%), in comparison to the control-ethanol (3.65%). This investigation showed that the infusions and essential oil of Aloysia gratissima present important antiproliferative effects on the Allium cepa cell cycle.


Asunto(s)
Antineoplásicos/farmacología , Aceites Volátiles/farmacología , Verbenaceae/química , Brasil , Ciclo Celular/efectos de los fármacos , Humanos , Medicina Tradicional , Cebollas/citología , Cebollas/efectos de los fármacos , Cebollas/fisiología
13.
Ann Hum Genet ; 39(3): 321-7, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1275443

RESUMEN

1. The three structural gene loci of human alcohol dehydrogenase have been studied in liver, jejunum and lung from 300 newborns in a triracially mixed population of Bahia, Brazil. 2. The frequency of the ADH23 allele was 0-1392, suggesting that the ADH23 allele is less frequent in Negroes. 3. A new ADH2 variant was identified. The electrophoretic pattern was interpreted as due to a new allele which is provisionally called ADH2Bahia. 4. By electrophoretic classification the 'atypical' variant was found in 2-8% of the sample. A question is raised regarding the ancestral origin of the 'atypical' variant in the population. Because this variant is common in Japanese it may have reached the present day population of Bahia through their American Indian ancestors. 5. Subjective estimation of the proportions of beta chains by giving scores to the liver isozymes alphaalpha, alphabeta and betabeta showed a clear relationship between the fetal weight and the beta chain activity. 6. The proportion of beta chains in the liver is significantly less when there is no enzyme activity in the lung, indicating some synchronous 'turning on' mechanism for alcohol dehydrogenase synthesis in both tissues.


Asunto(s)
Oxidorreductasas de Alcohol/análisis , Mapeo Cromosómico , Isoenzimas/análisis , Alelos , Peso Corporal , Brasil , Electroforesis , Femenino , Frecuencia de los Genes , Genética de Población , Humanos , Recién Nacido , Yeyuno/enzimología , Hígado/enzimología , Pulmón/enzimología , Masculino , Fenotipo , Grupos Raciales
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