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Biomedical subjects

A A Ferreira

Publications and source records attributed to A A Ferreira.

At least 19 recordsLinked to original sources
PubMed2005

Antinociceptive effect from Ipomoea cairica extract.

Ipomoea cairica L. Sweet (Convolvulaceae) is used in Brazilian folk medicine for the treatment of rheumatism and inflammations. Ipomoea cairica ethanolic extract (100, 300, 1000 and 3000 mg/kg; per os) induced dose-dependent reduction of response in the formalin test inflammatory phase in mice. The same dose range did not modify neurogenic pain in formalin test, tail-flick reflex latency, carrageenan-induced paw edema, and Rota-Rod test motor performance. From the bio-active fraction 3,5-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid were obtained. These compounds have been previously reported to have analgesic and antioxidative effects. A possible explanation for the antinociception is that somehow the compounds present in the extract reduced the release of pro-nociceptive mediators unrelated to carrageenan-induced edema, such as histamine. Interestingly, caffeoylquinic acid derivatives have been reported to inhibit histamine release on in vitro models. The isolated caffeoylquinic acids could explain, at least in part, the antinociceptive effect of Ipomoea cairica polar extract.

Analgesics↗
PubMed2005

Developments in the rat adjuvant arthritis model and its use in therapeutic evaluation of novel non-invasive treatment by SOD in Transfersomes.

The aim of this study was firstly to refine a rat model of arthritis, the adjuvant arthritis (AA) model, by studying the time course of the disease, introducing new evaluation methods such as haematological and biochemical parameters in order to identify the main stages of the disease. An optimisation of treatment schedule and evaluation criteria was developed. This refinement provided novel non-invasive anti-inflammatory treatment of the AA with SOD by using mixed lipid vesicles specially developed for transdermal delivery, Transfersomes (Tfs), this being the second major aim. The time course of AA includes a first stage: 1 day after the disease induction, the induced paw volume more than doubled and the paw circumference increased by approx. 50%. Two weeks later, another stage occurred where the disease shifted from the local arthritis form towards polyarthritis: an additional increase of volume and circumference of the induced and non-induced paws, occurred. The animals also started to loose weight around day 14 after the disease induction. Radiographic observable lesions increased correspondingly. Treatment of animals, started at day 1 after induction, by epicutaneous application of SOD-Tfs showed that 1 mg SOD/kg body weight is more efficient than 0.66 mg SOD /kg body weight. As a positive control, SOD liposomes intravenously injected were used for comparison and confirmed the biological efficiency of epicutaneously applied SOD in Tfs. SOD solution and empty Tfs epicutaneously applied exerted no effect. In addition, epicutaneous application of SOD-Tfs used prophylactically was able to suppress the induced rat paw oedema. Radiographic images showed less joint lesions in SOD-Tfs treated animals in comparison with control and placebo treated rats. It was shown for the first time that SOD incorporated into Tfs and applied onto a skin area not necessarily close to the inflamed tissue is able to promote non-invasive treatment of induced arthritis.

Animals↗
PubMed2005

Myelin basic protein accumulation is impaired in a model of protein deficiency during development.

During the development of the central nervous system (CNS) there is a great possibility of permanent effects in consequence of environmental disturbances. Nutritional deficiency is one of the factors that impair the normal CNS formation. In general, the protein deficiency evokes, beyond the damages in the maturation of nervous system, several consequences in body growth, biochemical maturation, motor function and the major cognitive functions. These effects were observed in undernourished children all over the world. Even in a restricted period, the malnutrition status may evoke permanent impairments in feeding behavior and in metabolism. Rats submitted to malnutrition during development, showed a marked decrease in the number of myelinated fibers. This condition may reflect a failure in the beginning of the wrapping of axons by oligodendroglial processes and/or a delay in the myelin synthesis. Myelin basic protein (MBP) is an intracellular oligodendrocyte protein that is directly related to the formation of the myelin sheath. In this study we verified the temporal pattern of MBP expression, by immunohistochemical and immunoblotting analyses, in a model of protein malnutrition induced during the first half of the lactation period. We showed that MBP expression was impaired in our malnutrition model and that some of the effects were maintained in adulthood, with possible consequences in the maturation of myelin sheath.

Aging↗
PubMed2002

Automatic flow system with voltammetric detection for diacetyl monitoring during brewing process.

Diacetyl can be determined by adsorptive stripping voltammetry after derivatization with o-phenylenediamine. The method may be applicable to the determination of diacetyl in different foods, being a good alternative to other analytical methods. In this work an on-line automated analytical system for diacetyl determination in beer is described. A hanging mercury drop electrode voltammetric flow detector was used, and the analyte was determined without the traditional deoxygenation procedure. The method was successfully applied to the determination of diacetyl during beer fermentation and in the final product. The automation strategy used was based on a flow network similar to those used in multicommutated flow systems, with a pervaporation unit used for diacetyl separation. The developed system was tested in real conditions in the monitoring of brewing processes. The results obtained were similar to those obtained with the usual GC-ECD methodology in the 5-600 ppb range. The analytical rate of the developed method is about 12 determinations/h.

Autoanalysis↗
PubMed2000

Antinociceptive, anti-inflammatory and bronchodilator activities of Brazilian medicinal plants containing coumarin: a comparative study.

This work studied the antinociceptive, antiinflammatory and bronchodilator activities of hydroalcoholic extracts (HAEs) from Torresea cearensis, Justicia pectoralis, Eclipta alba, Pterodon polygaliflorus and Hybanthus ipecacuanha. These plants are largely used in north-eastern Brazil for respiratory tract diseases, and have in common coumarin, one of their active principles. The antinociceptive effects of all HAEs in mice were similar, and the inhibition of the acetic acid-induced writhing was 35-55% with 200 mg/kg, p.o. At this dose, the effect ranged from 41-77% with the formalin test in mice, and all the HAEs inhibited preferentially the 2nd phase of the response. In one case (P. polygaliflorus), the effect was partially reversed by naloxone. Except for the HAE from T. cearensis (200 mg/kg, p.o.) which inhibited carrageenan-induced edema by 47%, the others presented no effect orally but showed a significant activity intraperitoneally. On the other hand, T. cearensis was not active in the dextran model, while inhibitions with the other ones were lower than 30%. The bronchodilator activities of J. pectoralis and P. polygaliflorus HAEs as determined in isolated guinea-pig trachea were the most active.

Analgesics, Non-Narcotic↗
PubMed2000

2'3'Cyclic nucleotide 3'phosphodiesterase immunohistochemistry shows an impairment on myelin compaction in hypothyroid rats.

The effects of hypothyroidism on oligodendroglial differentiation and myelination are for the first time studied by immunohistochemical localization of an early oligodendroglial marker, the 2'3'cyclic nucleotide 3'phosphodiesterase (E.C. 3.1.4.37-CNPase), in developing rats. Two groups received methimazol; one during gestation (H) and another postnatally (PN). One H sub-group received thyroxine after birth (T). We observed a delay in CNPase expression followed by a decrease in the number of CNPase immunoreactive fibers in both H and PN groups. The T sub-group was not different from controls. Furthermore, the immunoreactive fibers, in mature hypothyroid animals, showed a continuous pattern of staining in contrast with a discontinuous one in controls. Myelinogenesis is a highly regulated timed event. CNPase links myelin related proteins to the cytoskeleton also interacting with membrane lipids during extension and wrapping of the oligodendroglial process around the axon (ensheathment phase). In mature myelinated fiber the CNPase is absent from compact myelin sheath, being located only in the inner and outer loops and in paranodal loops. Thus, our data suggest a disorder in myelin compaction and point once more to the post-natal period as critical for the mechanisms that are thyroid hormone regulated in myelinogenesis.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1996

BCG vaccination in low birth weight newborns: analysis of lymphocyte proliferation, IL-2 generation and intradermal reaction to PPD.

OBJECTIVE: To study vaccinal scar formation and post-vaccinal immune response in newborns with birth weight ranging from 2000 to 2499 g vaccinated in the first week of life with intradermal bacille Calmette-Guérin (BCG) (Moreau-Rio de Janeiro strain). METHOD: Specific immune response to PPD was assessed in 30 low birth weight newborns (mean birth weight = 2311.7 +/- 122.1 g; mean gestational age = 38.1 +/- 1.8 weeks) in comparison to 56 control infants (mean birth weight = 3198.9 +/- 267.2 g; mean gestational age = 38.5 +/- 1.2 weeks. RESULTS: Low birth weight infants have an efficient immune response to vaccinal stimulus when compared to control infants as judged by specific in vitro lymphocyte proliferation (mean SI = 9.7 +/- 12.9 vs SI = 8.8 +/- 10.0, P = 0.72) and IL-2 production (mean SI = 3.1 +/- 3.4 vs SI = 2.6 +/- 2.0, P = 0.38). Intradermal reaction to PPD was also comparable in both groups (mean induration diameter = 9.5 +/- 5.1 mm vs 9.6 +/- 5.0 mm, P = 0.94). CONCLUSION: These data suggest that low birth weight newborns show a good immune response to BCG, thus reinforcing the inclusion of such infants in regular vaccination programs with intradermal BCG.

BCG Vaccine↗
PubMed1982

Spleen lymphocyte populations in patients with Hodgkin's disease--properties of cells with different densities.

Spleen lymphocytes from five patients with Hodgkin's disease (HD) type mixed cellularity and five normal controls were studied. An increased percentage of 'null cells' was observed in three out of the five patients studied. The two other patients had increased percentage of T lymphocytes. Lymphocytes from spleen with HD had a decreased ability to respond to suboptimal concentrations of T cell mitogens. When these cells were fractionated in a discontinuous density gradient a subpopulation of cells, unable to respond to Con A, was recovered from the dense cell fractions. The implications of the present findings to the understanding of the physiopathological changes in HD are discussed.

Adolescent↗
PubMed1976

Thoracoscopy as an aid to the diagnosis of diaphragmatic injury in penetrating wounds of the left lower chest: a preliminary report.

In an attempt to evaluate the place of thoracoscopy, the investigation was performed on 11 patients with penetrating wounds of the left lower chest, who had no definite clinical or radiological indication for operation. In 6 patients the diaphragm was seen clearly, and in 2 of these an unsuspected diaphragmatic injury was found. Both injuries were later confirmed at operation. The other 4 patients had intact diaphragms and were successfully treated conservatively. It is suggested that thoracoscopy is a useful aid in the diagnosis of left-sided, diaphragmatic injury and that the best results are obtained if it is performed within 24 hours of the injury.

Adult↗
PubMed1976

Malacoplakia of the prostate confused with clear cell carcinoma.

Primary malacoplakia of the prostate is a rare benign disease, which is frequently mistaken for carcinoma and granulomatous prostatis. The surgical and clinical course of a patient with obstructive hypertrophy of the prostate is reviewed after an initial incorrect diagnosis of clear cell carcinoma. Experience in defining the lesion during the transurethral resection is presented. The pathogenesis, morphological structure and unique microscopic appearance of malacoplakia, characterized by large mononuclear cells associated with small laminated concretions, are described and illustrated.

Adenocarcinoma↗
PubMed1976

Observations on abdominal injuries in the Nigerian Civil War.

A retrospective study of 331 patients who sustained abdominal injuries during the Nigerian Civil War 1967-70 and were treated at Base Surgical Centres in the 3 Field Ambulance Nigerian Army is made. The most commonly injured organs are small intestine 148, caecum and colon 80, liver 69, spleen 26, stomach 28 and kidney 24. Case fatality rate is 33.8%. Factors influencing case mortality rate include type of organ injured, number of organs hit by penetrating missile, peri-operative complication. Other factors, not measurable in this study are mentioned. The few patients with injuries severally to the pancreas or the gall bladder who reached the operating table alive, all showed injuries to some other organs; these are among those with the highest mortality rates. Comparisons are made with similar studies from the Second World War 1942-45 and the Korean War 1952-53.

Abdominal Injuries↗