Showing papers by "Federal University of São Paulo published in 1994"

GPI-anchored glycoconjugates from Trypanosoma cruzi trypomastigotes are recognized by lytic anti-alpha-galactosyl antibodies isolated from patients with chronic Chagas' disease.

Abstract: The target molecules on the cell surface of Trypanosoma cruzi trypomastigotes reacting with lytic anti-α-galactosyl antibodies from chronic patients with Chagas' disease (Ch anti-Gal) have been purified by solvent extraction and identified as glycoconjugates migrating in the 74-96-kDa range (F2 antigen) and in the 120-200-kDa range (F3 antigen) on SDS-PAGE. The F3 antigen was tested for binding to Ch and normal human serum (NHS) anti-Gal and to MoAb 3C9. We observed that Ch antiGal and MoAb 3C9, but not NHS anti-Gal, bind strongly to the trypomastigote glycoconjugates. These antibodies, however, did not compete with each other for binding to F3 molecules, indicating that they are recognizing different epitopes

Epstein-Barr virus detection in invasive and pre-invasive lesions of the uterine cervix.

Abstract: In the present study, our aim was to investigate whether EBV DNA could be found in association with invasive and pre-invasive cervical cancer lesions. We hypothesize that EBV is not merely a commensal agent when present in malignant cervical lesions. DNA was extracted from cervical scrapings followed by nested PCR-based amplification. The patients were 66 women with high grade cervical intraepithelial neoplasia and 14 women with invasive cervical cancer. The control group consisted of 89 women with a normal Pap smear and colposcopy as well as a negative HPV DNA test. Analysis of our results, in conjunction with the work of other authors, leads us to propose that EBV is not merely a commensal agent when present in malignant cervical lesions. The presence of DNA from EBV is significantly associated with cervical cancer.

β2-Agonists and death from asthma

Abstract: ESCOLA PAULISTA MED,DEPT PEDIAT,DIV ALLERGY CLIN IMMUNOL & RHEUMATOL,BR-04023 Sao Paulo,BRAZIL

Prejunctional regulatory actions of androgens on a hormone sensitive muscle.

Abstract: The influence of androgens and time course of effects induced by hormone deprivation were examined on the spontaneous transmitter re- lease in the levator ani (LA) muscle of 30–180-day-old male rats. The resting membrane potential (RMP) and miniature endplate potentials (mepps) were recorded intracellularly from LA muscle fibers of intact animals or gonadectomized at different ages. In intact animals, the frequency of mepps increased proportionately to the muscle fiber growth up to 60 days, stabilizing thereafter. Gonadectomy at any age did not affect the RMP, but increased the frequency of mepps by 65% to 140%. The effect was detected after 15 days and was unrelated to the degree of muscle atrophy. Independently of the age of gonadectomy control values of mepp frequency were restored after 90 days, while the accompanying postjunctional changes persisted. These results indicate that androgens exert a prejunctional inhibitory influence on the spontaneous transmitter release in the rat LA muscle. The transient nature of the prejunctional effect induced by hormone deprivation indicates an adjustment of nerve terminals to persistent postjunctional alterations. © 1994 John Wiley & Sons, Inc.

pathogenesis of Uncus Deformation and Vertebral Artery Compression : histologic Investigations of the Uncus and Dynamic Angiography of the Vertebral Artery in the Cadaveric Cervical Spine

Abstract: Twenty-one cervical spines were collected from fresh cadavers (12 male, nine female), their ages ranging from 10 to 90 years (mean 49.47). After removing muscle debris from the spines, they were mounted and tested on a device to passively reproduce the main movements of the spine. The degree of motion in flexion-extension and lateral bending significantly decreased from group A (ages 10-49 years) to group B (51-90 years) (p < 0.005) and was directly correlated with the amount of cervical spine degenerative alterations. The incidence of these alterations, classified according to Lysell (1969), was highest at C5-6. On the testing machine, dynamic angiography of the vertebral artery showed an impingement with extrinsic compression of the vessels in four of 28 successful injections. The histologic serial sections of the uncus showed a characteristic pattern of ossification-deformation: a newly formed cartilaginous tissue tipping the apex of the uncus, forming a double protruding contour of the apex, rapidly ossifying, and appearing to deform outward together with the disk degeneration and consequently decreasing in height.

Contribution of energy-filtering TEM to the detection of calcium: Application to mast cells

Abstract: Summary The ultrastructural distribution and quantification of calcium in mast cells prepared by anhydrous processing was investigated by energy-filtering transmission electron microscopy (EFTEM) using a Zeiss 902 electron microscope. Optimal conditions for calcium detection were determined using inorganic (calcium phosphate) and organic (calcium-loaded chelex beads) standards with known amounts of calcium. Electron energy-loss spectroscopy (EELS) revealed calcium at the L2,3 edge and also at the M2,3 edge for all specimens examined. Comparison with X-ray microanalysis confirmed the results obtained with EELS. Electron spectroscopic imaging (ESI) was applied for mapping calcium both in standards and in cells and we showed that mast cell granules were the main site of calcium localization. Although, results have shown that a combination of analytical techniques is required to obtain reliable results.