Morphocytochemical, immunohistochemical and ultrastructural characterization of the head kidney of fat snook Centropomus parallelus.

This study characterized the structure and the morphocytochemical, immunohistochemical and ultrastructural aspects of the head kidney (HK) of the fat snook Centropomus parallelus. The HK is enclosed by a thin capsule of connective tissue, from which fine trabeculae originate and branch into the interior of organ. In the parenchyma, there are aggregates of lymphoid cells containing populations of lymphocytes T immunopositive for CDRO45, in a nodular arrangement, around blood vessels and melano-macrophage centres. Among the cells that constituted these aggregates and surrounded them, were macrophages and monocytes, and their precursors, with strong immunopositivity for CD68, along with cells of the granulocytic lineage in various phases of maturation positive for lysozyme and PAS. Macrophages and chromaffin and interrenal cells are also present. Ultrastructurally, the HK comprises a reticulum-endothelial stroma consisting of endothelial cells, reticulocytes of the fibroblast type and macrophage type and a parenchyma with increased cellularity, principally blood cells of the erythrocytic, granulocytic, lymphocytic, monocytic and thrombocytic series.

Rudimentary eyes of squamate fossorial reptiles (Amphisbaenia and Serpentes)

The rudimentary characteristic of the eyes of fossorial animals raises some questions regarding its evolution and functionality. Would these eyes result from atrophy or from stagnated development? How would its visual function work? Anatomical investigations of these organs are the fundamental preamble to answer those questions, which are still little explored by the literature. In this article we have studied anatomical aspects of the eyes of three species of fossorial reptiles, within the suborder Amphisbaena (Amphisbaena alba, Amphisbaena mertensi, Leposternon infraorbitale), as well as a species within the ophidian suborder (Typhlops brongersmianus). The minuscule eyes (1-2 mm diameter) were visualized through a scale, a translucent area which corresponds to the spectacle. This spectacle is a thinner and transparent scale, covering a conjunctival sac. The retrobulbar space was filled with the harderian gland. The eyes of Typhlops presented an oval shape, whereas Amphisbaena specimens presented cup-shaped eyes. In Amphisbaenian sclera is comprised of cartilage, while the thin sclera of Typhlops consists of connective tissue and striated muscle fibers. The retina presented all the typical layers found in vertebrates, regardless the species. The characteristics involved in the fossil adaptation of these species include: reduced size of the eyeball, rudimentary cornea, absence of the anterior chamber, presence of a complex iris-ciliary body, and lens with amorphous nucleate cells. The analysis of the eye morphology of these animals suggests that there might be a specific function concerning light perception.

Migration behaviour and pathogenesis of five ascarid nematode species in the Mongolian gerbil Meriones unguiculatus.

To understand the characteristic features of the Mongolian gerbil, Meriones unguiculatus, as an animal model of ascarid infections, the migration behaviour and pathogenesis of larvae were investigated in experimentally infected gerbils. Embryonated eggs from each of Toxocara canis, Baylisascaris procyonis, B. transfuga, Ascaris suum, and A. lumbricoides were orally inoculated into gerbils and larvae were recovered from various organs at designated periods. In T. canis-infected gerbils, larvae were present in the liver 3 days after infection and in the skeletal muscle and brain via the heart and lungs at a similar rate. In B. procyonis- and B. transfuga-infected gerbils, larvae were present in the lungs within 24 h after infection, with some having reached the brain by that time. After 24 h, larvae of B. procyonis tended to accumulate in the brain, while those of B. transfuga accumulated in skeletal muscles. In A. suum- and A. lumbricoides-infected gerbils, larvae remained in the liver on day 5 post-infection and elicited pulmonary haemorrhagic lesions, which disappeared 7 days after initial infection. Thereafter, no larvae of any type were recovered. Ocular manifestations were frequently observed in T. canis- and B. procyonis infected gerbils, but were rare in B. transfuga-infected gerbils. In the cases of A. suum and A. lumbricoides, migration to the central nervous system and eyes was extremely rare, and larvae had disappeared by 2 weeks post-infection. Fatal neurological disturbances were observed in B. procyonis-infected gerbils, whereas irreversible non-fatal neurological symptoms were observed in the case of B. transfuga.

Early nuclear alterations and immunohistochemical expression of Ki-67, Erb-B2, vascular endothelial growth factor (VEGF), transforming growth factor (TGF-beta1) and integrine-linked kinase (ILK) two days after tamoxifen in breast carcinoma.

The purpose of the present study was to evaluate breast carcinoma samples before and two days after treatment with tamoxifen in order to analyse early histopathological alterations--particularlynuclear alterations-- as well as immunohistochemical expression of Ki-67, Erb-B2, VEGF, TGF-beta1 and ILK proteins. Twenty one cases of invasive ductal and lobular breast carcinoma were studied. Patients were submitted to biopsy of the lesion and, after confirmation of the diagnosis, they received 20 mg of tamoxifen a day, beginning two days before surgery. The samples obtained during biopsy and after surgery were stained with HE for histopathological diagnosis. Estrogen receptor was positive in 18 cases and negative in 3. The immunohistochemical method was applied for the detection of Ki-67, Erb-B2, protein, vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-beta1) and integrin linked kinase (ILK). Two days after tamoxifen treatment, the following results were observed: 1) decrease in the cell volume, chomatine condensation, nucleoli less evident and clearly defined nuclear limits; 2) significant reduction in the expression of Erb-B2 protein and significant increase in the expression of TGF-beta1 protein; 3) expression of others proteins (Ki-67, VEGF and ILK) was not altered during the indicated time frame. Our results suggest that analyzing nuclear alterations and expression of Erb-B2 and TGF-beta1 proteins would be useful to assess the initial response to tamoxifen.

Immunosuppression in undernourished rats: the effect of glutamine supplementation.

OBJECTIVE: The aim of our study is to determine the effect of a 30-day-period caloric restriction (CR) upon the immune response of rats and the influence of glutamine upon mononuclear cells proliferation and cytokine production. METHODS: Male albino Wistar rats were submitted to CR receiving an amount of food equivalent to 50% of the mean amount consumed by the control animals. We measured the incorporation of [2-14C]-thymidine by lymphocytes obtained from the spleen and mesenteric lymph nodes, plasma glucose and glutamine concentration, as well as cytokine production by cultivated cells, in the presence of glutamine. RESULTS: Rats submitted to CR presented reduced body weight (49%) and decreased splenic leukocyte number. CR led to a reduction in the proliferative response of lymphocyte. Spleenocytes from CR animals produced less gamma-interferon and interleukins 1, 4 and 10 in 48 h culture than did those from control rats. The same pattern is observed in cells obtained from the mesenteric lymph nodes. The addition of glutamine 2mM to the culture medium restored spleen and mesenteric lymph node cells' proliferative response and the production of interleukin 2 by cells obtained from the spleen and from the mesenteric lymph nodes. CONCLUSIONS: The present data reinforce that undernutrition decreases in vitro immune cell function and indicates that, in such circumstances, glutamine supplementation could reverse some of the changes observed in the functionality of cultured immune cells. The presence of the amino acid at physiological concentration, however, reinforces the diversion of the immune response towards a Th(1)-like response.

Structural, cytochemical, immunocytochemical and ultrastructural characterization of blood granulocytes of the roadside hawk Buteo magnirostris (Gmelin, 1788) (Avian, Falconiform).

In the peripheral blood of the roadside hawk, Buteo magnirostris, the following types of granulocytic leucocytes were identified: heterophil, eosinophil and basophil. The heterophils presented acidophilic and spindle shaped granules, the eosinophils possess spherical eosinophilic granules and the basophils showed spherical and basophilic granules. The heterophils and eosinophils presented positive cytochemical reaction to glycogen and basic polyaminoacid, while the eosinophils presented sudanophilic granules, which were also positive for myeloperoxidase. The heterophils, alone, presented positivity for acid phosphatase in some granules and immunoreactivity to TGF-beta1 was observed only in the cytoplasm of the eosinophils. Electron microscopy demonstrated the heterophil granules as predominantly spindle shaped, being strongly electron-dense, while the eosinophils had numerous uniformly electron-dense spherical granules and the basophils presented three different types of granules identified according to their electron-density and the aspect of their matrix.

Morphological and ultrastructural study of the thrombocytes and leukocyte granulocytes of Salminus maxillosus (Characiformes, Characidae).

The thrombocytes and leukocytes of 'dourado' fish Salminus maxilosus peripheral blood were studied by means of light microscopy and transmission electron microscopy techniques. In respect to the morphological and ultrastructural aspects of thrombocytes and granulocytes, the cellular elements that appear with high frequency in the light microscopy preparations stained by the Rosenfeld method, three different types of granulocytes could be differentiated at the electron microscope, based on the ultrastructural aspect of the cytoplasmic elements: type I granulocyte that possibly corresponds to the type I neutrophil described under light microscopy; type II granulocyte is possibly the cell identified as type II neutrophil by the morphological analysis; type III granulocyte is equivalent to the eosinophils described in the samples stained by Rosenfeld methods.

Interaction of gum arabic, maltodextrin and pullulan with lipids in emulsions.

The interaction of gum arabic, maltodextrin and pullulan with lipids in emulsion systems was investigated. Interfacial tension and interfacial viscosity measurements revealed that only gum arabic could adsorb and form a viscoelastic film at the oil-water interface. Good emulsifying activity was demonstrated for gum arabic, whereas fine emulsions could not be produced from the other polysaccharide solutions and oil. Frequency-dependent increases in the storage and loss moduli were observed for all the polysaccharide solutions. Such rheological behavior did not substantially change when maltodextrin and pullulan were mixed with oil to form emulsions. However, the frequency-dependence of the dynamic moduli disappeared in the gum arabic-stabilized emulsion, suggesting the formation of a network structure in which oil droplets could form junctions with gum arabic chains. The results on the inhibition of lipid oxidation by polysaccharides suggest that gum arabic protected lipids from the attack of lipoxygenase and free radicals by adsorbing at the oil droplet surface.

Aspectos morfológicos e citoquímicos dos glóbulos sangüíneos de Caiman crocodilus yacare (Daudin, 1802) (Reptilia, Crocodilia) / Morphological and cytochemical observations of blood cells of Caiman crocodilus yacare (Daudin, 1802) (Reptilia, Crocodilia)

Foram utilizados 10 jacarés Caiman crocodilus yacare, colhendo-se 5 ml do sangue periférico de cada animal. A análise morfológica foi realizada após coloraçäo por Leishman. Para estudo citoquímico, empregaram-se os métodos do PAS, do Sudan black B, da o-toluidina e do azul de bromofenol. Foram identificados 7 tipos celulares: eritrócitos, trombócitos, heterófilos, eosinófilos, basófilos, linfócitos e monócitos azurófilos. Os eritrócitos nucleados apresentam formato elíptico com atividade mitótica e positividade citoplasmática para o azul de bromofenol. Os trombócitos säo de formato elíptico, com citoplasma abundante nos pólos, contendo grânulos de glicogênio e núcleo com sulcos profundos. Heterófilos, grosseiramente esféricos, mostram núcleo esférico excêntrico e citoplasma repleto de grânulos corados em salmäo, de formato fusiforme, em baqueta, oval ou esférico. A citoquímica nestas células revelou a presença de glicogênio, grânulos citoplasmáticos positivos para azul de bromofenol e parcialmente sudanófilos e positivos para mieloperoxidase. Eosinófilos mostram-se esféricos com núcleo lenticular excêntrico e citoplasma com grânulos esféricos ou ovais róseos positivos para Sudan e mieloperoxidase, porém fracamente para o azul de bromofenol. Basófilos apresentam formato esférico, de tamanho menor em relaçäo aos demais granulócitos, núcleo esférico central e citoplasma com poucos grânulos fortemente basófilos. Linfócitos mostram-se polimórficos com núcleo de formato irregular, citoplasma escasso com projeçöes e grânulos azurófilos. Monócito azurófilo, de formato esférico, núcleo excêntrico e citoplasma basófilo contendo grânulos azurófilos abundantes

Identification and characterization of a sialidase released by the salivary gland of the hematophagous insect Triatoma infestans.

Sialidases (EC 3.2.1.18) are commonly found in viruses, bacteria, fungi, protozoa, and vertebrates, but not in invertebrates. We have previously reported the presence of a new sialidase activity in the gut of exclusively hematophagous insects of the Triatoma genus, which transmit Chagas' disease (Amino, R., Acosta, A., Morita, O. M., Chioccola, V. L. P., and Schenkman, S. (1995) Glycobiology 5, 625-631). Here we show that this sialidase is present in the salivary gland of Triatoma infestans, and it is released with the saliva during the insect bite. The sialidase was purified to homogeneity (>5000 times) to a specific activity of more than 20 units/mg. It elutes from a gel filtration column with a volume corresponding to the size of 33 kDa, and it migrates as a single 26-kDa band in SDS-polyacrylamide gel electrophoresis, which is unusually smaller when compared with other known sialidases. T. infestans sialidase hydrolyzes preferentially alpha2-->3-linked sialic acids at pH 4-8, with maximal activity between pH 5.5 and 6.5, which is compatible with the optimal pH of secreted sialidases. The sialidase is competitively inhibited by 2-deoxy-2, 3-dehydro-N-acetyl-neuraminic acid (Ki = 0.075 mM) and differently from many sialidases, with exception of Salmonella typhimurium sialidase, it is inhibited competitively by HEPES (Ki = 15 mM). The fact that T. infestans sialidase is released with the saliva and can hydrolyze sialyl-LewisX blood groups, which are the ligands for selectins, suggests that it might have a role in the blood feeding.

Estudos hematológicos em Oreochromis niloticus (Linnaeus, 1758) (Cichlidae, Teleostei) - Parte I / Hematological studies in Oreochromis niloticus (Linnaeus, 1758) (Cichlidae, Teleostei) - Part I

Avaliou-se o hemograma e a morfologia celular em amostras de sangue periférico obtidas de 10 peixes da espécie Oreochromis niloticus. Parte das mesmas foi utilizada para o estudo da hematimetria, isto é, contagem de eritrócitos (x = 2,35 x 10 elevado à sexta potência/mm ao cubo mais ou menos 0,12), taxa de hemoglobina (x = 7,04g/dL mais ou menos 0,38), hematócrito (x = 27,85 por cento mais ou menos 1,62), HCM (x = 30,31pg mais ou menos 1,64), VCM (x = 118,6u ao cubo mais ou menos 3,53), CHCM (x = 25,78 por cento mais ou menos 1,72), contagem global de leucócitos (x = 16,08 x 10 ao cubo/mm ao cubo mais ou menos 1,28), contagem de trombócitos (x = 61,69 x 10 ao cubo/mm ao cubo mais ou menos 5,96), sendo a avaliaçäo da morfologia das células do sangue realizada através do estudo de extensöes sanguíneas submetidas à coloraçäo de Wright. Os eritrócitos e trombócitos nucleados apresentaram-se elípticos; neutrófilos e eosinófilos esféricos de tamanho variável, com o núcleo também esférico, apresentaram citoplasmas abundantes, ligeiramente basófilo e altamente acidófilo, respectivamente. Näo foram vistas as formas polimorfonucleares dessas células. Os basófilos apresentaram núcleo esférico e granulaçöes metacromáticas. Os monócitos e os linfócitos assemelharam-se morfologicamente aos dos mamíferos

Açäo dos raios X corpo total sobre os neutrófilos do sangue periférico em primata Cebus apella (macaco prego) / Effects of whole-body X-radiation on the neutrophils of the peripheral blood of the primate Cebus apella (weeping capuchin)

Amostras de sangue periférico foram obtidas de cinco primatas Cebus apella (macaco prego), antes e após exposiçäo aos raios X corpo inteiro, na dose única de 25,8 mC/kg (100R). Parte das amostras foi utilizada para a contagem global de cariosquizes e o restante para a realizaçäo de extensöes sanguíneas e submetidas à coloraçäo de Wright e aos seguintes métodos citoquímicos: ácido periódico Schiff (PAS) para a identificaçäo de glicogênio, Sudan black B para a detecçäo de fosfolipídios e o-toluidina-água oxigenada para a demonstraçäo da mieloperoxidase. Com o método de Wright foram observadas aos 1, 3 e 6 dias após exposiçäo à radiaçäo, alteraçöes nucleares e citoplasmáticas. Após aplicaçäo dos métodos citoquímicos acima referidos, foram observados, de modo geral, nos mesmos períodos de tempo após irradiaçäo: alteraçäo no padräo de distribuiçäo dos grânulos de glicogênio, grânulos mieloperoxidase positivos e sudanófilos de neutrófilos. No que diz respeito a cariosquizes, constatou-se um aumento dos mesmos após 1 dia, persistindo até o 3§ dia após irradiaçäo. Noventa dias após, näo foi observada nenhuma alteraçäo acima referida

Effect of fatty acid-rich diets on thymocyte proliferation and thymus involution during growing.

The effect of poly-unsaturated and saturated fatty acid-rich diet on the proliferation response of T and B lymphocytes in vitro was investigated. Also, a mitotic index of thymocytes and of thymus epithelial reticular-like cells and thymic involution coefficient were examined in vivo. w-6 PUFA-rich diet enhanced the rate of T (eightfold) and B (fourfold) lymphocyte proliferation, whereas saturated fatty acids did not show an important effect. However, both fat-rich diets increased the mitotic index of thymocytes and thymus involution index in vivo. These findings suggest that fat-rich diets may accelerate thymus involution during growing, possibly aggravating the impairment of the immune function which usually occurs under this condition.

Effect of monosodium glutamate treatment during neonatal development on lipogenesis rate and lipoprotein lipase activity in adult rats.

Monosodium glutamate (MSG) has been shown to alter several neuroendocrine functions in neonatally treated rats. To evaluate possible alterations in lipogenesis rate and lipoprotein lipase (LPL) activity, male and female rats were injected during the neonatal period with MSG or saline (controls). In male MSG rats, an increase in lipogenesis of liver and retroperitoneal adipose tissues was observed. Triton WR 1339 (an LPL inhibitor) administration decreased retroperitoneal lipogenesis in these animals. In female rats, MSG-treatment increased lipogenesis only in gonadal and retroperitoneal adipose tissues. No change was observed in hepatic lipogenesis and the Triton administration did not change retroperitoneal lipogenesis. LPL activity was increased in the gonadal and retroperitoneal adipose tissues in male and female MSG-treated rats. These data suggest that there is a specific sex-dependent response in the development of MSG-induced obesity.

Effects of whole-body x-irradiation on the peripheral blood of primate Cebus apella

The effects of ionizing radiation on the peripheral blood elements of primate Cebus apella were examined after a single 25.8mC/kg (100 R) dose of whole-body X-ray. We determined the number of white blood cells,neutrophils, osophils, basophils,lymphocytes,monocytes anderythrocytes up to 90 days after exposure of 5 animals. Hemoglobin content and microhematocrit were also determined. Under these experimental conditions, the total number of leukocytes was reduced from 9440/mm***3 to 5660/mm***3 on day6, mainly because of a decrease inthe lymphocyte population from 5843.2/mm***3 to 2349.0/mm***3 on day 6. No significant differences were observed in the values of erythrocytes, neutrophils,eosinophils,basophils,monocytes,hemoglobin content and microhematocrit. All hematological parameters studied returned tonormal values by day 90 after a single irradiation dose of 100R

Topochemistry of blood cells of the Gallus domesticus (Aves, Galliforme).

Blood smears of both male and female chicken Gallus domesticus were analysed by using the following topochemical methods: a) Periodic acid-Schiff (PAS) for glycogen. b) Mercury-bromophenol blue for protein. c) O-Toluidine for myeloperoxidase. d) Sudan black B for lipid. The PAS reaction revealed glycogen in the cytoplasm of all thrombocytes and in a few heterophils. The presence of proteins was evidenced in all types of cells. However variation in the intensity of staining of protein granules was observed in the fusiform structures of the heterophils. A negative reaction for myeloperoxidase was found in all cells. Although some evidence of myeloperoxidase activity was show in the polymorphonuclears it was not enough to ascertain a positive reaction. Lipids were detected in the cytoplasm of few heterophils, eosinophils and monocytes.

Topochemistry of blood cells of the Gallus domesticus (Aves, Galliforme)

Extensöes de sangue periférico de aves (macho e fêmea), foram submetidas a um estudo topoquímico que permitiu as seguintes conclusöes: com o PAS, a presença de glicogênio nos trombócitos e alguns heterófilos; com o azul de bromofenol (proteína) positividade em todos os elementos celulares, com intensa reatividade da regiäo equatorial dos grânulos fusiformes de heterófilos; com o método da orto-toluidina-água oxigenada (mieloperoxidase), reatividade discutível nos polimorfonucleares e negativa nos demais tipos de células e com Sudan black (lipídios) uma positividade em alguns heterófilos, eosinófilos e monócitos

Effects of whole-body X-irradiation on the peripheral blood of primate Cebus apella.

The effects of ionizing radiation on the peripheral blood elements of primate Cebus apella were examined after a single 25.8 mC/kg (100 R) dose of whole-body X-ray. We determined the number of white blood cells, neutrophils, eosinophils, basophils, lymphocytes, monocytes and erythrocytes up to 90 days after exposure of 5 animals. Hemoglobin content and microhematocrit were also determined. Under these experimental conditions, the total number of leukocytes was reduced from 9440/mm3 to 5660/mm3 on day 6, mainly because of a decrease in the lymphocyte population from 5843.2/mm3 to 2349.0/mm3 on day 6. No significant differences were observed in the values of erythrocytes, neutrophils, eosinophils, basophils, monocytes, hemoglobin content and microhematocrit. All hematological parameters studied returned to normal values by day 90 after a single irradiation dose of 100 R.

Neonatal treatment with monosodium glutamate increases plasma corticosterone in the rat.

Monosodium glutamate (MSG) has been shown to alter several neuroendocrine functions in neonatally treated rats. To evaluate for possible alterations in the hypothalamic-pituitary-adrenal axis, we injected rats during the neonatal period with MSG or saline (controls). An increase in basal plasma corticosterone levels associated with a blunted circadian variation was observed. Ether exposure produced a significant elevation in plasma corticosterone concentration in both groups of animals. However, while the increase in controls was 181.3% for male and 193.9% for female rats, in the MSG-treated rats it was only 60.7 and 31.6%, respectively. The intraperitoneal administration of high dexamethasone doses blocked corticosterone secretion in both groups. However, whereas the lowest dose (0.10 microgram/kg) suppressed corticosterone secretion in control animals, it was ineffective in MSG-treated rats. The morphological study of adrenals revealed signs of a hyperfunctional state in MSG-treated rats. These data suggest that the central lesions produced by MSG treatment disrupt the regulation of the hypothalamic-pituitary-adrenal axis.