Molecular detection of Leishmania spp in Lutzomyia longipalpis in the city of Lavras, Minas Gerais, Brazil

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.

Measuring higher order optical aberrations of the human eye: techniques and applications

In the present paper we discuss the development of "wave-front", an instrument for determining the lower and higher optical aberrations of the human eye. We also discuss the advantages that such instrumentation and techniques might bring to the ophthalmology professional of the 21st century. By shining a small light spot on the retina of subjects and observing the light that is reflected back from within the eye, we are able to quantitatively determine the amount of lower order aberrations (astigmatism, myopia, hyperopia) and higher order aberrations (coma, spherical aberration, etc.). We have measured artificial eyes with calibrated ametropia ranging from +5 to -5 D, with and without 2 D astigmatism with axis at 45º and 90º. We used a device known as the Hartmann-Shack (HS) sensor, originally developed for measuring the optical aberrations of optical instruments and general refracting surfaces in astronomical telescopes. The HS sensor sends information to a computer software for decomposition of wave-front aberrations into a set of Zernike polynomials. These polynomials have special mathematical properties and are more suitable in this case than the traditional Seidel polynomials. We have demonstrated that this technique is more precise than conventional autorefraction, with a root mean square error (RMSE) of less than 0.1 æm for a 4-mm diameter pupil. In terms of dioptric power this represents an RMSE error of less than 0.04 D and 5º for the axis. This precision is sufficient for customized corneal ablations, among other applications

Efeito do exercício físico na hipertensäo renovascular crônica em ratos / Effect of physical exercises in chronic renovascular hypertension in rats

Este experimento foi realizado tendo por objetivo verificar a influência do exercício físico na pressäo arterial e no controle de peso corporal em ratos normais e ratos com hipertensäo renovascular crônica, pelo método de Godblatt um rim, um clipe (HG1). Foram utilizados 40 ratos Wistar com peso entre 150 e 200 g, divididos em 4 grupos: I e II - Normotensos com e sem exercício físico; IIIe IV - Hipertensos (HG1)com e sem exercício. O exercício físico constou de nataçäo durante 15 minutos, 2 vezes ao dia por 5 semanasconsecutivas. A pressäo arterial dos animais foi verificada aos 7, 14, 21, 28 e 35 dias por meio de um eletrosfigmógrafo (NARCOBIOSYSTEMS, Houston, USA), com cabos acoplados do microfone KOROTKOF e bomba de compressäo de cauda (cuff pump) e o peso corporal foi verificado diariamente antes do treinamento. Os resultados foram analisados, através do teste T de "Student" para dados pareados e näo-pareados. Pelo resultados obtidos observou-se, decorrente do exercício, que os animais normotensos apresentaram reduçäo significativa do ganho de peso corporal. Por outro lado, os animais hipertensos submetidos ao exercício físico, apresentaram uma reduçäo significativa de PA, sugerindo que nos animais hipertensos (HG1), submetidos ao exercício físico de nataçäo, por um período de 5 semanas, a pressäo arterial é mais sensível a alteraçöes do que o peso corporal. E que a nataçäo reduz o ganho de peso corporal em animais normotensos sem alterar de forma significativa a PA.

Desenvolvimento de um instrumento computadorizado para medida do poder refrativo da córnea (videoceratógrafo) / Development of a computerized instrument (videokeratograph)for the measurement of the corneal refractive power

Objetivo: Resumir o desenvolvimento de um Videoceratógrafo (ou menos precisamente, Topógrafo de Córnea) projetado e fabricado no Brasil. Métodos: Discos de Plácido pintados num anteparo em forma de cone säo refletidos pela córnea. As imagens passam por um sistema óptico de aumento e säo focalizadas num CCD ('' Charge Coupled Device ''; nada mais do que uma abreviaçäo para câmeras fabricadas com a tecnologia de semicondutores) atrás do cone. O sinal do CCD é enviado para uma placa de captura de imagens ('' frame grabber '')intalada em um PC-IBM compatível. Por meio de algoritmos de processamento de imagens, extraem-se das imagens digitalizadas distâncias de borda dos Discos de Plácido. Estes valores säo inseridos em algoritmos com modelos matemáticos de curvatura da córnea, resultando no cálculo da dioptria de aproximadamente 5.760 pontos. Resultados: Assim como em outros aparelhos importados, imprime-se na tela do computador um mapa colorido plano com código de cores relativo aos valores de dioptria. Para um conjunto de 9 esferas de raios: 5.50; 5.75; 6.00; 6.25; 6.75; 7.00; 7.25; 7.50; 7.75 mm obteve-se um desvio médio de 0.1 para dioptria e 0.02 mm para o raio. Foram analizados computacionalmente 5.760 pontos para cada esfera. Em uma amostra de 20 córneas obteve-se desvio médio de 0.2 dioptrias com relaçäo ao topógrafo EyeSys. Conclusöes: Podemos afirmar que o instrumento contruído obtém resultados equivalentes àqueles do intrumento importado.

Sex-related differences in the analgesic response to the rat tail immersion test

The analgesic response was evaluated by the tail immersion test in adult male (N = 30), female (N = 21) and androgenized female Wistar rats (N = 15). The reaction time for tail withdrawal from the hot water bath was faster for male than for female rats (3.48 +/- 0.12 vs 6.46 +/- 0.42 s). The reaction time of androgenized female rats was similar to that of male rats (3.08 +/- 0.16 s). Blockade of opiate receptors with naloxone (2 mg/kg, ip) decreased the sensitivity to the noxious stimuli in males (4.08 +/- 0.10 s) and in androgenized females (3.69 +/- 0.19 s) but increased it in female rats (5.01 +/- 0.41 s). These data show sex-related differences in the analgesic response evaluated by the tail immersion test and indicate that administration of androgens to newborn female rats affects their pain sensitivity.

Sex-related differences in cardiovascular responses to common carotid occlusion in conscious rats

Mean arterial pressure and heart rate were determined in conscious, unrestrained groups of 10 male, female and androgenized female Wistar rats 20 s (early pressor response) and 1 min (late sustained response) after bilateral carotid artery occlusion. The early pressor response, which is carotid reflex origin, was 40% greater in female than in male rats (45 ñ 2 vs 63 ñ 3 mmHg, respectively). The late sustained response, which is of central origin (probably ischemic), did not differ between male and female rats (32 ñ 2 vs 37 ñ 4 mmHg, respectively). The magnitude of the early pressor response of androgenized female rats (50 ñ 2 mmHg) was similar to that of male rats (45 ñ 2 mmHg) but the late sustained response was 19% smaller (26 ñ 2 mmHg). Common carotid occlusion caused increases in haert rate which were greater in female (51 ñ 9 and 34 ñ 9 beats/min in the early pressor response and late sustained response respectively) than in male rats (31 ñ 5 and 8 ñ 4 beats/min, respectively). In androgenized female rats, heart rate decreased during common carotid occlusion (34 ñ 7 and 35 ñ 8 beats/min after 20 s and 1 min, respectively). These data provide evidence that there are substantial sex-related differences in the cardiovascular responses to common carotid occlusion in conscoious rats and indicate that administration of androgens to newborn female rats affects the baroreceptor reflex control of their arterial pressure

Effect of testosterone on the pressor response to common carotid occlusion in gonadectomized conscious male rats with lesion of the median eminence

The influence of testosterone on the development of the pressor response to common carotid occlusion was investigated in control and median eminence-lesioned male rats. In control rats (N-9), gonadectomy performed 21 days before the experiments reduced by 22% (from 51 ñ 2 to 40 ñ 2 mmHg) and treatment with testosterone (330 µg for 4 days before the measurements) increased the initial peak pressor response (from 51 ñ 2 to 57 ñ 2 mmHg) which depends on carotid innervation. The maintained response which is of central origin (propably ischemic was less affected. In non gonadectomized rats (N=6), lesions of the median eminence (6 days) decreased the initial peak by 19% (from 52 ñ 2 to 42 ñ 3 mmHg) and the maintained response by 56% (from 32 ñ 2 to 14 ñ 1 mmHg). Sham-operated rats served as controls. In gonadectomized animals (N=6) the lesion reduced only the maintained response (from 23 ñ 2 to 11 ñ 1 mmHg). Testosterone supplementation restored the maintained response but did not alter the initial peak. These results indicate that the pressor response to common carotid occlusion in male rats is modulated by testosterone and that the depresiin in the maintained response caused by median eminence lesion can be reversed by steroid supplentation

Participation of opioid receptors in the modulation of the analgesic response by adrenal and gonadal glands

The invovlement of opiodi receptors in the analgesic response was evaluated by the tail-immersion test in simultaneously adrenalectomized and ovariectomized female Wistar rats (210-250g). The reaction time (mean ñ SEM) for tail withdrawal from hot water decreased significantly 2 weeks after surgery (3.52 ñ 0.20 s) when compared to intact animals (6.09 ñ 0.23 s). Hormonal replacement with dexamethasone (50*/day) did not affect reaction time (3.38 ñ 0.19 s). However, this response was restored by combined adrenal and gonadal steroid substitution (estradiol 5*g/day and progesterone 1.5*g 6h before the test) therapy (5.11 ñ 0.45 s) in animal treated with dexamethasone plus estradiol and 5.04 ñ 0.43 s in animals treated with dexamethasone plus estradiol plus progesterone). Naloxone (2mg/Kg decreased the reaction time of animals treated with adrenal and gonadal steroids (5.11 ñ 0.45 vs 4.15 ñ 0.44 and 5.04 ñ 0.43 vs 3.87 ñ 0.28 s, respectively, before and after naloxone) but failed to decrease it in rats treated with dexamethasone only (3.88 ñ 0.18 vs 4.34 ñ 0.25 s, before and after naloxone). These observations indicate that gonadal steroids are the most important steroid factors involved in the reaction time to tail immersion in hot water and confirm other reports that the opioid pathways modulating the neuronal circuitry require the presence of these hormones

The effect of tubero-infundibular dopaminergic neurons on prolactin and alpha-melanocyte stimulating hormone release

The effect of tubero-infundibular dopaminergic neurons (TIDA) on the release of prolactin (PRL) and alpha-melanocyte stimulating hormone (alpha-MSH) was studied in median eminence-lesioned (MEL) male rats (N = 6-28). Plasma PRL and alpha-MSH levels were significantly elevated 2(86.1 ñ 19.8 and 505.1 ñ 19.1 ng/ml), 4(278.7 ñ 15.5 and 487.4 ñ 125.1 ng/ml), 7 (116.2 ñ 16.2 and 495.8 ñ 62.6 ng/ml) and 14 (247.3 ñ 26.1 and 448.4 ñ 63.8 ng/ml) days after MEL when compared to sham-operated control animals (55.5 ñ 13.4 and 56.2 ñ 6.1 ng/ml, repectively). MEL altered plasma PRL and alpha-MSH levels in a diffential manner, with 1.5-to5.0-fold increase in PRL and an 8.0- to 9.0-fold increase in alpha-MSH. The increase of alpha-MSH levels occured abruptly and remained constant from days 2 to 14. These observations indicate that TIDA plays an important role in the pituitary release of PRL and alpha-MSH and provide evidence that the release of the two hormones occurs in a differential manner

The role of opioids in the analgesic response of rats during the estrous cycle

The analgesic response was evaluated by the tail immersion test in female rats during each phase of rhe estrous cycle. The reaction time (mean ñ SEM) for tail witdrawal from the hot water bath was faster during proestrus (5.78 ñ 0,28s) and decreased significantly during estrus (5.31 ñ 0.30s) and diestrus 1 (5.40 ñ 0.21s). Blockade of opiate receptors with naloxone (2mg/Kg, ip) invreased the sensitivity to the noxious stimulus only during proestrus (6.46 ñ 0.42 vs 5.02 ñ 0.41 s). These results suggest that the effects of gonadal steroids on nociception may involve an opioid pathway

Involvement of beta-adrenergic receptors in the differential release of gonadotropins in acutely orchidectomized rats

To determine the diferential release fo gonadotropins in acutely orchidectomized rats, a single injection of the beta-adrenergic blocker Bornaprolol (FM 24) was administered to the animals and plasma FSH levels weredetermined. FM 24 produced low plasma FSH levels only when injected 16 h before starting the blood collection and had no effect on FSH levels at 0,30 and 46 h after its administration. However, it produced low LH plasma levels at 0,16 and 30 h after administration. These findings confirm that pituitary beta-adrenergic receptors are involved in plasma LH release and suggest that they could also be involved in the differential release of FSH/LH

The efffect of age on the presssor reponse produced by common carotid artery occlusion in conscious rats

The pressor responses to s of common carotid artery occlusion were studied in conscious male rats of different ages. Compared to rats at the age of 2 months, the initial peak and the maintained response in 6-12 and 18 month old rats were well preserved. In 1-onth old rats, both components were significantly depressed but in 24-month old rats only the initial peak of the pressor response was markedly attenuated. These findings demonstrate that age is an important factor in the response to common carotid artery occlusion wich is more marked for the initial than the maintained response

Pressor responses to common carotid occlusion in female rats: effects of gonadectomy and treatment with gonadal steroid hormones

The pressor responses to common carotid occlusion were studied in conscious female rats throughout the estrous cycle, after gonadectomy and after gonadectomy followed by treatment with estrogen and progesterone. The initial peak pressor response was highest during proestrus and fell significantly over the remaining 3 days of the estrous cycle. The maintained pressor response was relatively unchanged throughout the cycle, except during diestrus 1 when it decreased markedly. Gonadectomy reduced and treatment with estradiol alone increased the initial pressor component, respectively. Treatment of gonadectomized rats with estradiol plus progesterone enhanced both components. These findings suggest that gonadal steroid hormones are important modulators of the pressor to common carotid occlusion

Persistência do canal arterial em irmãos / Patent ductus arteriosus in siblings

Os autores relatam, em 2 irmaos, a ocorrencia da persistencia do canal arterial (PCA), comprovada cirurgicamente. O achado torna evidente a implicacao genetica na transmissao dessa anomalia. Embora a literatura seja concordante quanto a preponderante responsabilidade de fatores extrinsecos na etiologia da PCA, a presente publicacao, sugere a causa genetica como responsavel