Evaluation of the population of NADPH-diaphorase-stained and myosin-V myenteric neurons in the ileum of chronically streptozotocin-diabetic rats treated with ascorbic acid.

We investigated the effect of the ascorbic acid on the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d)-stained and myosin-V myenteric neurons in the ileum of chronically diabetic rats. The study was performed 4 months after inducing experimental diabetes with streptozotocin. Diabetic rats showed increased (p<0.05) glycaemia and glycated haemoglobin. Three groups were compared, i.e., nondiabetic rats, diabetic rats and diabetic rats treated with ascorbic acid. Myosin-V immunohistochemistry and NADPH-d histochemistry were employed. We investigated the areas of 500 cell bodies of myosin-V neurons and of 500 NADPH-d-stained neurons from all groups. The quantitative analysis was performed by using an area of 8.96 mm(2) from each ileum. The two groups of diabetic rats and diabetic rats treated with ascorbic acid showed reduction in the number and an increased area of the myosin-V-immunostained myenteric neurons. In addition, we observed increased relative proportion of NADPH-d-stained neurons in diabetic rats and diabetic rats treated with ascorbic acid. However, the area of these neurons in the diabetic rats group was larger than those evidenced in the nondiabetic rats and diabetic rats treated with ascorbic acid.

Arrangement of the tunica muscularis of the ileum, cecum and colon at the transition between the small and the large intestines of swine.

The arrangement of the bundles of muscular fibers in the transition between the small and the large intestines was studied in 12 male adult crossbred swine by dissection, after immersion in 50% nitric acid solution. The connection between the small and the large intestines was formed by the association of the muscular tissue, the connective tissue and the fat tissue. The tunica muscularis of these organs was organized in thin thread-like bundles and wide ribbon-like bundles of variable width and thickness. The superficial bundles of the longitudinal stratum of the tunica muscularis of the ileum established the continuity with the large intestine; the deep bundles penetrated into the ileal papilla. The limit between the cecum and the ascending colon was externally marked by the sulcus cecocolicus dorsalis and ventralis. The connection between the cecum and the ascending colon was formed by bundles of muscular fibers coming from the ileum, and the taeniae ventralis, lateralis and medialis of the cecum. Some bundles of muscular fibers from the ascending colon and the cecum headed toward the sulcus cecocolicus. The median bundles of muscular fibers of the taenia ventralis of the cecum, near the termination of the ileum, were arranged to form a loop around the termination of the ileum, mixing with the musculature of the ascending colon at the level of this junction.

Paracoccidioides brasilienses isolates obtained from patients with acute and chronic disease exhibit morphological differences after animal passage.

The basis for virulence in Paracoccidioides brasiliensis is not completely understood. There is a consensus that the sequential in vitro subcultivation of P. brasiliensis leads to loss of its pathogenicity, which can be reverted by reisolation from animal passage. Attention to morphological and biochemical properties that are regained or demonstrated after animal passage may provide new insights into factors related to the pathogenicity and virulence of P. brasiliensis. We evaluated morphological characters: the percentage of budding cells, number of buds by cell and the diameter of 100 mother cells of yeast-like cells of 30 P. brasiliensis isolates, before and after animal passage. The isolates were obtained from patients with different clinical forms of paracoccidioidomycosis (PCM): acute form (group A, n=15) and chronic form (group C, n=15). The measurement of the yeast cell sizes was carried out with the aid of an Olympus CBB microscope coupled with a micrometer disc. We measured the major transverse and longitudinal axes of 100 viable cells of each preparation. The percentage of budding cells as also the number of buds by cell was not influenced by animal passage, regardless of the source of the strain (acute or chronic groups). The size values of P. brasiliensis isolates from groups A and C, measured before the animal passage exhibited the same behavior. After animal passage, there was a statistically significant difference between the cell sizes of P. brasiliensis isolates recovered from testicles inoculated with strains from groups A and C. The maximum diameter of mother cells from group A isolates exhibited a size of 42.1 microm in contrast with 32.9 microm exhibited by mother cells from group C (p<0.05). The diameter of 1500 mother cells from group A isolates exhibited a medium size of 16.0 microm (SD +/- 4.0), a value significantly higher than the 14.1 microm (SD = +/- 3.3) exhibited by 1500 mother cells from group C isolates (p<0.05). Our results reinforce the polymorphism exhibited by P. brasiliensis in biological material and the need for further investigations to elucidate the role of morphological parameters of the fungus in the natural history of the disease.

Effects of maternal proteic undernutrition on the neurons of the myenteric plexus of the duodenum of rats.

The purpose of this study was to verify the effects of proteic undernutrition on the neurons of the myenteric plexus from the duodenum of Wistar rats. Twenty-four animals at the age of 60 days were divided in four groups, which were named according to the period their mothers received hypoproteic ration (8%). Some segments of duodenum were subjected to histological treatment and stained with hematoxilin-eosin and some were used for whole mount preparations stained with Giemsa. We observed small, medium-sized and large neurons grouped in ganglia of various shapes. It was concluded that the maternal proteic undernutrition does not affect the organization of the myenteric plexus and that animals submitted to undernutrition during gestation and lactation, when normally fed, show neurons with strongly basophilic cytoplasm and larger cellular bodies than those from control animals.

Streptozotocin-induced diabetes duration is important to determine changes in the number and basophily of myenteric neurons.

The aim of present study was to evaluate the number and basophily of cell bodies of myenteric neurons in the ileum of rats with diabetes mellitus induced by streptozotocin. Four groups of rats were used: diabetes was induced in two (D) whereas the other two worked as controls (N). Animals were sacrificed six (6N, 6D) or nineteen (19N, 19D) weeks after diabetes induction. A segment of the terminal portion of the ileum of each rat was obtained and stained with Giemsa's solution, for whole-mount preparation studies. Forty fields were analyzed in each animal, and the number and basophily intensity of cell bodies were recorded. After counting, the following mean numbers of neurons/mm2 were obtained: 6N=593.1 +/- 95.75, 6D=639.1 +/- 130.8, 19N=580.1 +/- 175.6 and 19D=402.0 +/- 144.8. The analysis of basophily shown that highest frequency of neurons with weak/intermediary basophily was verified in 6D group (55.3%), whereas the groups 6N, 19N e 19D presented 38%, 36% e 40% respectively. The statistical analysis showed that a long period is necessary to decrease the number of neurons/mm2 in the rat ileum after diabetes induction, and that there was a reduction in basophily intensity in diabetic rats after 6 weeks of treatment, and such cells do not recover after a longer period (19 weeks).

Effect of maternal protein deprivation on morphological and quantitative aspects of the myenteric plexus neurons of proximal colon in rats.

We have studied the morphological and quantitative aspects of the myenteric plexus neurons of the proximal colon in rats (Rattus norvegicus of Wistar strain) submitted to a protein deprivation during prenatal and lactation periods. Twenty pregnant dams were divided in four groups labeled according to the kind of nourishment they were given: Group NN, normal diet; Group DN, low protein diet during prenatal period, and normal diet during lactation period; Group ND, normal diet during prenatal period, and low protein diet during lactation period; Group DD, low protein diet during prenatal and lactation periods. Histological analyses were developed with proximal colon segments using the haematoxylin and eosin staining method. Membrane preparations were stained by Giemsa's method. The statistical analysis has demonstrated no significant difference among the means of neurons found in the four studied groups. It was noticed that the animals under protein deprivation during prenatal and lactation periods presented greater quantity of large and strongly basophilic myenteric neurons. This suggests that neurons have accumulated protein in the cytoplasm.

Effects of protein and vitamin B deficiency on blood parameters and myenteric neurons of the colon of rats.

The aims of this work were to evaluate the effects of the deficient ingestion of protein and vitamin B on the biochemical and hematologic parameters and on the NADH- and NADPH-diaphorase positive myenteric neurons. The control animals (n=10) received commercial chow and the experimental rats (n=10) received chow with protein level reduced to 8% during 120 days. At the time of killing blood was collected for assessment of the blood and hematologic parameters and the ascending colon for quantitative analysis of the neurons of the myenteric plexus. It was observed that the reduction of the protein level to 8% coupled to the reduction of the levels of vitamin B in adult rats neither led to qualitative or quantitative changes on red or white blood cells, nor decreased globulin levels, induced the formation of edema or gave rise to clinical signs typical of protein or vitamin B deficiency. On the other hand, the experimental protocol led to less weight gain, change on the body composition with fat deposition; decrease of the values of serum total protein and albumin; reduction of the area of colon and density of nitrergic and NADH-diaphorase myenteric neurons inferior to the expected.

Arachnoid granulation affected by subarachnoid hemorrhage.

The purpose of this study was to investigate using light microscopy the fibrocellular components of arachnoid granulations affected by mild and severe subarachnoid hemorrhage. The erythrocytes were in the channels delimited by collagenous and elastic bundles and arachnoid cells, showing their tortuous and inter-communicating row from the pedicle to the fibrous capsule. The core portion of the pedicle and the center represented a principal route to the bulk outflow of cerebrospinal fluid and erythrocytes. In the severe hemorrhage, the fibrocellular components are disorganized, increasing the extracellular channels. We could see arachnoid granulations without erythrocytes, which cells showed big round nucleus suggesting their transformation into phagocytic cells.

[A micromesoscopic study of human arachnoid granulations]. / Estudo micro-mesoscópico das granulações aracnóides humanas.

The functional anatomy of the arachnoid granulations of the upper sagittal sinus was studied by means of micromesoscopic techniques in order to contribute to elucidating aspects of drainage pathways of the cerebrospinal fluid through their fibrous components. The arrangement of fibrous elements was analysed at the base of the peduncle, peduncle, middle and apex of granulation. The analysis of serial sections shows collagen bundles at the base of the peduncle with a predominantly circular morphology, longitudinally directed towards the peduncle's longest axis. These bundles arise in the middle of the granulation, them branch off towards its apex and periphery. The elastic bundles present an arrangement similar to that described for collagen bundles, delimiting with such bundles intercommunication channels from the base of the peduncle up to the apex of the granulation. Bundles of reticular fibers arranged in between the collagen meshes were found at the base of the peduncle. The fibrous capsule of granulation is composed of collagen bundles and a small number of elastic fibers.

[Morphological study of human arachnoid granulations with reference to their classification]. / Estudo morfológico das granulações aracnóides humanas com referência a sua classificação.

Stereomicroscopic and microscopic study showed human arachnoid granulations with different morphology that we classified in simple and lobate. Simple granulations were small and completely involved by fibrous capsule that delimited a continuous subdural space from the pedicle to the apex. Lobate granulations were bigger than the simple; in the apex the fibrous capsule was thinner than in other regions, and fused with granulation periphery causing interruption of subdural space. Simple granulations might be an initial development stage; lobate granulations would represent a higher development stage, with ideal morphologic structure for absorption of the CSF.

[The connectivity between the greater occipital nerve and adjacent structures: anatomo-clinical considerations]. / Estudo da conectividade entre o nervo occipital maior e estruturas adjacentes: considerações anátomo-clínicas.

In order to offer anatomical basis that aid for clinical interpretation of headache of cervical origin a macro-mesoscopic study of greater occipital nerve and its subcutaneous rise out site was accomplished. The authors observed that in its course this nerve delineates angles and direction shifts that can stand for critical points in etiology of occipital pain, so that in its subcutaneous rise out region both occipital artery and vein shape the vasculo-nervous bundle wrapped by sheath of fibrous connective tissue which has continuity and contiguity relation with the adjoining epimysium and perimysium. From our results, anatomo-clinical aspects are discussed.

Quantitative study of the myenteric plexus of the stomach of rats with streptozotocin-induced diabetes.

The purpose of the present study was to investigate the morphological and quantitative alterations of the myenteric plexus neurons of the stomach of rats with streptozotocin-induced chronic diabetes and compare them to those of non-diabetic animals. Samples from the body of the stomach were used for whole-mount preparations stained with NADH-diaphorase and for histological sections stained with hematoxylin-eosin. It was observed that diabetes cause a significant decrease on the number of neurons.

Regional differences in the number and type of myenteric neurons of the ileum of rats: a comparison of techniques of the neuronal evidentiation.

We carried out this study with the purpose of analyzing the density of neurons of the myenteric plexus in the mesenteric, intermediate and antimesenteric regions of the ileum of rats. Whole-mounts stained with four different techniques were employed. Through countings under optic microscope in an area of 8.96 mm2 we found the following neuronal means with the techniques of Giemsa, NADH-diaphorase histochemistry, NADPH-diaphorase and acetylcholinesterase, respectively: mesenteric region 2144.40+/-161.05, 1657.80+/-88.23, 473.80+/-19.62, 905.25+/-22.40; intermediate region 1790.60+/-128.24, 1265.20+/-141.17, 371.30+/-27.84, 770.25+/-33.12; antimesenteric region 1647.0+/-76.67, 981.80+/-68.04, 298.50+/-22.75, 704.50+/-69.38. We conclude that there is a variation of neuronal density around the intestinal circumference and this fact independs on the technique used to stain the neurons, and that in a single region the neuronal density varies with the technique employed. We also call attention for the identification of the site were countings were carried out, so that the results of research in this area are not compromised.

Morphological and quantitative study of the myenteric plexus of the ascending colon of rats subjected to proteic desnutrition.

We carried out this study with the purpose of contributing on the effects of the proteic desnutrition on the morphological aspects and quantitative analysis of the neurons in the myenteric plexus of the ascending colon of adult Rattus norvegicus. Twenty adult rats were divided into two groups: in one of them, we offered a normal ration with proteic level of 22% (control group) and in the other, a ration with a proteic level of 8% (experiment group) during 120 days. We did the whole-mount preparations for the ascending colon and stained them with the Giemsa technique and the histochemical technique of NADH-diaphorase. The rats with proteic desnutrition showed a body weight, on average, to be 35.1% less than those of the control group, and the colon was on average, 26.8% shorter and 6.7% narrower. Thus, it was to be expected that the colon of animals with proteic desnutrition had a neuronal density 31.62% greater than the rats of the control group. Nevertheless, the difference with the Giemsa technique was on average 18.4%, demonstrating a mean neuronal loss of 13.25%.

Morphological and quantitative analysis of the neurons of the myenteric plexus of the cecum of streptozotocin-induced diabetic rats.

The purpose of this work was to study the neurons of the myenteric plexus of the cecum of rats with chronic streptozotocin-induced diabetes. We used four experimental groups of animals. In groups D2 and D8 animals were killed two and eight months, respectively, after diabetes induction and groups C2 and C8 were used as controls. We carried out whole-mount preparations stained with Giemsa and NADH-diaphorase. We verified that the diabetes did not alter the shape and disposition of the myenteric ganglia; it provoked decrease on the neuronal density and increase on the incidence of weakly basophilic neurons. The effects of streptozotocin caused dilatation of the cecum still evidenced two months after induction, but no more observed on the eight months after induction. The smaller incidence of neurons in group D8 relative to group C8 was due to the early loss related to the drug toxicity and later to the aging in diabetic condition.

Neuron number in the myenteric plexus of the ascending colon of rats. A comparative study using two staining techniques.

We carried out this study with the purpose of comparing the neuronal density in antimesocolic and intermediate regions of the colon of rats. We used the ascending colon of ten seven-months old Wistar rats. With the Giemsa method we found 29,046 neurons/cm2 on the antimesocolic region and 30,968 neurons/cm2 on the intermediate regions. With the NADH-diaphorase technique 12,308 neurons/cm2 on the antimesocolic regions and 8798 neurons/cm2 on the intermediate regions were evidenced. The number of NADH-diaphorase positive neurons is significantly less than the number of Giemsa-stained neurons and that this difference is enhanced on the intermediate regions of the intestinal circumference. Therefore, to compare the number of neurons of an intestinal segment of a same species at the same age, it is necessary to take into consideration the technique employed and the region of the intestinal circumference from where the sample was obtained.

Number and size of myenteric neurons of the duodenum of adult rats with acute diabetes.

This study had as its purpose to assess the effects of acute diabetes induced by streptozotocin (35 mg/kg body weight) on the number and size of the myenteric neurons of the duodenum of adult rats considering equally the antimesenteric and intermediate regions of the intestinal circumference. Experimental period extended for a week. Neuronal counts were carried out on the same number of fields of both regions of the duodenal circumference and measurements of neuronal and nuclear areas on equal numbers of cells. Number and size of the myenteric neurons stained with Giemsa were not significantly different between groups. On the other hand, the proportion of NADH-positive neurons increased from 18.54% on the controls to 39.33% on the diabetics. The authors discuss that this increased reactivity probably results from a greater NADH/NAD+ ratio, described in many tissues of diabetic animals, which has consequences on the modulation of the enzymes that use these cofactors and whose activity is detected by the NADH-diaphorase technique.

Evaluation of the areas of neuronal cell bodies and nuclei in the myenteric plexus of the duodenum of adult rats.

This study compared the areas of cell body and nucleus profiles of the myenteric neurons in the antimesenteric and intermediate regions of the duodenum of adult rats. Five male rats were used. The duodenum was removed and dissected to whole-mount preparations, which were stained by the Giemsa technique. The areas of cell body and nucleus profiles of 100 neurons, 50 from each region, of each animal, were assessed with image analyser. Based on the global mean+/-SD of the areas of cell body profiles, neurons were labelled as small, medium or large. It was observed that the neurons did not differ significantly in size or incidence between the antimesenteric and intermediate regions. However, the nuclei of the small and medium neurons were significantly smaller in the latter region. It is discussed that the smaller nuclear size could be related to the cell bodies being slightly smaller on this region and to a possible smaller biosynthetic activity which would influence nuclear size.

Morphologic and quantitative study of the myenteric neurons of the jejunum of malnourished rats (Rattus norvegicus).

We studied the effects of maternal proteic desnutrition on the neurons of the myenteric plexus of the jejunum of rats from Rattus norvegicus species. It was used litters of female rats which received diet with normal proteic level during gestation and lactation (group NN), normal diet during gestation and hypoproteic diet during lactation (group ND); hypoproteic diet during gestation and normal diet during lactation (group DN); hypoproteic diet during both gestation and lactation (group DD). After weaning all the animals received diet of normal proteic level until the 60th day of age, when they were killed. The jejunum of the animals was subjected to whole-mount preparations stained by the method of Giemsa and used for the morphologic and quantitative analyses of the neurons of the myenteric plexus. We verified that maternal proteic malnutrition does not cause decrease on the number of myenteric neurons per unit area of jejunum in rats, but elicits mechanisms which assure that, when the animal again receives normal proteic level diet (22%) there occurs storage of proteic material on the cytoplasm of the neurons, thus rendering them larger and strongly basophylic.

Morphological and quantitative study of the myenteric plexus of the duodenum of streptozotocin-induced diabetic rats.

The purpose of this work was to study the morphological and quantitative alterations of the myenteric plexus neurons of the duodenum of rats with acute and chronic streptozotocin-induced diabetes and establish a comparison with non-diabetic animals. Samples of duodenum were destined to histological sections stained by Hematoxilin-Eosin and to membrane preparings stained by the Giemsa and NADH-diaphorasis methods. Small, medium and large neurons were found, with a predominance of medium ones on chronic and acute diabetic animals. It was verified that most of the neurons of diabetic and non-diabetic animals have an eccentrical nucleus and thus this characteristic is not an indicative of degenerative process. It was observed that in diabetes there is a decrease in the number of myenteric neurons. It is argued that this initial decrease is due to the toxic effects of the drug and not to the physiopathology of diabetes itself, and also that the expressive smaller proportion of neurons on the chronically diabetic animals is due to the immediate loss related to streptozotocin and the further consequences of aging during nine weeks of diabetes.