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J Lara

Publications and source records attributed to J Lara.

54 records · Page 3Linked to original sources
PubMed1987

Microscopic structure of the brain of Barbus meridionalis Risso. I. Telencephalon.

The telencephalon of Barbus meridionalis is composed of two oval telencephalic lobes separated by a medial ventricle and joined exclusively by the anterior commissure. Histologically, the dorsal and ventral telencephalic areas are well defined, the limiting plane between them being a cell free zone. In the ventral area it is possible to distinguish the following parts: dorsal, supracommissural, postcommissural, lateral, intermedia and the nucleus entopenduncularis. In the dorsal area there are three peripheral longitudinal zones--medialis, dorsalis and lateralis--together with a central zone; caudally situated is a posterior dorsolateral region which is the main receptor site for olfactory fibers and closely associated to this is the nucleus tenia. The olfactory projections to the telencephalon course along two bundles: the medial and the lateral olfactory tracts. The telencephalon projects to diencephalic regions via three large bundles: the lateral and medial telencephalic bundles and the strio-medullary system.

Animals↗
PubMed1986

Structural organization of the optic tectum of Barbus meridionalis Risso. I. Inner strata (SPV, SAC and SGC).

The histological features of the three deepest strata of the Optic Tectum of Barbus meridionalis were studied with several staining and impregnation techniques. The boundaries between SPV, SAC and SGC were easily established and furthermore the myelinization pattern of the SAC is described. Several neuronal types were distinguished according to their dendritic and axonal features. Pyriform multipolar neurons were found in the SPV; in the SAc, pear-shaped, horizontal and multipolar neurons; in the SGC, fusiform, horizontal, multipolar and pyriform neurons. Some of the pyriform neurons of the SAC are described with axonal characteristics which has allowed us to consider these neurons as a new type of efferent tectal neuron.

Animals↗
PubMed1986

Structural organization of the optic tectum of Barbus meridionalis Risso. II. Outer strata (SFGS, SO and SM).

The present work deals with the histological organization of the three outer strata of the optic tectum of Barbus meridionalis. As far as general features are concerned, of noteworthy interest are the absence of myelin in the SM and the ordered pattern of myelinic distribution of the SO. The SFGS shows a more irregular appearance than the SM and SO. It was only possible to observe with clarity several neuronal types in the SO and SFGS, whereas in the SM no clear neuronal types could be seen. The SFGS was seen to contain pyramidal neurons with spiny dendrites in the SM, together with fusiform, multipolar and horizontal neurons. In this latter type we have described neurons with ascending axons emerging from the soma or from the base of a principal dendrite. The SO contains neurons whose dendrites are distributed mainly on the horizontal plane, in each case showing certain particular features.

Animals↗
PubMed1985

The stratum album centrale in the optic tectum of Cyprinus carpio.

The most outstanding characteristics of the stratum album centrale of the optic tectum of Cyprinus carpio were analyzed by light and electron microscopy, with special reference to the morphology and ultrastructure of the neurons with cell bodies in this stratum. Neurons belonging to the stratum album centrale itself are described, both vertical and horizontal in development, together with others which are found in this and the periventricular stratum. The possible involvement of this zone in the cytoarchitectural development of the tectal structure is discussed.

Animals↗
PubMed1985

A quantitative study of the nucleus rotundus of the carp.

The present work describes the results of a quantitative study of the Nucleus Rotundus of C. carpio aimed at determining the volume of the nucleus as a whole and the partial volumes corresponding to the rostral and caudal zones. The overall neuronal density of the nucleus and the density of light and dark cells which forms the neuronal population of the Nucleus Rotundus were also determined; the light cells were the most represented. Most cells were found in the rostral portion while the caudal one is mainly composed of large amounts of fibres.

Animals↗
PubMed1983

The optic tectum of the carp: pyramidal neurons of the SFGS.

We have studied the stratum fibrosum et griseum superficiale (SFGS) of the carp optic tectum with optic and electron microscopy. This stratum is a dense neuropil with disordered appearance, in which numerous neuronal bodies of different characteristics and variable distribution according to the tectal regions are intercalated, more abundant in the dorsomedial zones of the tectum. Within these neuronal types, the most characteristic of SFGS are the large pyramidals of vertical development. Such neurons shows an ascendant dendritic shaft, very developed in the stratum marginale, a thinner dendritic shaft in the basal pole and a descending axon that reaches the internal zones of the stratum griseum centrale. Glial elements are highly associated to the pyramidal neuron bodies. The synaptic contacts are abundant and of various types, specially on the spinous dendritic branches which lie in the stratum marginale.

Animals↗
PubMedDate not supplied

Mycotic aneurysm of the aortic arch.

A 61-year-old diabetic woman presented with a mycotic aneurysm of the aortic arch, also involving the left subclavian and vertebral arteries, caused by Staphylococcus aureus. Two months before, she had suffered from staphylococcal septic arthritis in her left knee. The patient was treated with antibiotics and an emergency operation was performed involving aneurysm excision and in situ synthetic graft replacement. She died on the fourth postoperative day from hemorrhagic shock.

Aneurysm, Infected↗
PubMedDate not supplied

Distribution of neuropeptide Y-like immunoreactive fibers in the cat thalamus.

Neuropeptide Y-like immunoreactivity was studied in the thalamus of the cat using an indirect immunoperoxidase method. The densest network of immunoreactive fibers was observed in the nucleus (n.) paraventricularis anterior. In the anterior, intralaminar and midline thalamic nuclei, as well as in the n. geniculatum medialis, n. geniculatum lateralis, n. habenularis lateralis, n. medialis dorsalis, n. lateralis posterior and n. pulvinar a low density of neuropeptide Y-like immunoreactive fibers was observed. Neuropeptide Y-like fibers were totally absent in the n. ventralis lateralis, n. ventralis medialis, n. ventralis postero-medialis and n. ventralis postero-lateralis. In addition, neuropeptide Y-like perikarya were found in the n. parafascicularis, n. suprageniculatus, n. geniculatum lateralis ventralis, n. medialis dorsalis and n. lateralis posterior.

Animals↗
PubMedDate not supplied

Calbindin D-28K and NADPH-diaphorase activity are localized in different populations of periglomerular cells in the rat olfactory bulb.

Calbindin D-28k (CaBP) immunocytochemistry and NADPH-diaphorase (ND) histochemistry have been combined in the rat olfactory bulb by successive incubations of the same sections. The outer strata showed a similar neuronal staining pattern for both markers with positive periglomerular neurons (although the CaBP-stained periglomerular cells were six-fold more abundant than the ND-active ones) and larger neurons scattered in the glomerular and external plexiform layers. Both populations of periglomerular cells were distinct but they did not show specific morphological characteristics nor a predominant distribution around ND-positive and negative glomeruli. The colocalization study demonstrates that the larger ND and CaBP-stained juxtaglomerular cells, identified according to their size, location and processes branching patterns as two types of short axon cells (superficial short-axon and Van Gehuchten Cells) were also independent populations.

Animals↗
PubMedDate not supplied

[A mid-term clinical and hemodynamic evaluation of the Wessex and Hancock II bioprostheses].

The purpose of this study is to compare clinically and hemodynamically the Wessex and Hancock II porcine bioprostheses. We compared functional class and data from echo-Doppler in 34 Wessex bioprostheses (group A) with those in 42 Hancock II bioprostheses (group B). We subdivided group A into A1 and A2. A1 was made up of 23 Wessex manufactured since 1986. A2 constituted 11 Wessex made before 1986 which belonged to a series with some variations in the manufacturing process, and in which some early dysfunctions have been described. We compared data from these sub-groups between each other as well as with those of group B. The groups were homogeneous in age, sex, patients body surface and the time elapsed since the prosthetic implant. The mean mitral gradient, the mitral area, the peak aortic gradient and the regurgitation incidence were similar in groups A and B. In A2 the mean mitral gradient was significantly superior to that of group B (7.1 +/- 1.1 mmHg vs 5.4 +/- 1.4 mmHg; p less than 0.01), and the mitral area showed a tendency to be inferior, although with no statistical significance. The functional class of the patients was similar in all the groups. We conclude that the Wessex bioprosthesis presents hemodynamic data and functional class similar to those of the Hancock II, with the exception of a sub-group of Wessex manufactured before 1986 which presents mean mitral gradients superior to the others and which would warrant further studies.

Bioprosthesis↗
PubMedDate not supplied

[Ultrasonographic changes in the gallbladder wall in non-gallbladder diseases].

Alterations of the gallbladder wall is a well known sonographic sign of acute cholecystitis. But thickening of the gallbladder wall is also found in patients without intrinsic gallbladder disease. We present our experience on this regard in patients with cirrhosis, acute viral hepatitis, infectious mononucleosis, halothane hepatitis, fulminant hepatic failure, malaria due to plasmodium falciparum, heart failure, severe malnutrition due to gastric obstruction, septicemia, pyogenic hepatic abscess, amoebic hepatic abscess and in a 14 years old patient with fracture of the skull-acute anemia-shock. Most of these diseases affected the liver directly or indirectly. Knowledge of these alterations of the gallbladder wall in these circumstances are important in order to avoid a the erroneous diagnosis of acute cholecystitis.

Acute Disease↗
PubMedDate not supplied

[Splenic pseudocystic. Report of a case].

Splenic pseudocysts represent 70 to 80% of the non parasitic cysts of this organ. Malaria, infectious mononucleosis, tuberculosis and t. pallidum infection are predisposing factors. Cystic characteristics are determined by CT-SCAN and ultrasound. Final diagnosis is achieved by hystological examination. This is a case report.

Adult↗
PubMedDate not supplied

[Esophageal varices sclerosis in portal hypertension caused by portal thrombosis secondary to protein C deficiency].

Portal thrombosis is a rare entity classified as idiopathic in 50% of the cases, being protein C deficiency a known cause. We present two cases complicated with portal hypertension diagnosed through sonography and protein C determined though laboratory technics. Complicating esophageal varices sclerosed and follow up at seven months and ten years respectively, satisfactory clinical evolution observed.

Adult↗