Biomedical subjects

M A de Oliveira

Publications and source records attributed to M A de Oliveira.

At least 19 recordsLinked to original sources

PubMed2006

Colleters in Bathysa nicholsonii K. Schum. (Rubiaceae): ultrastructure, secretion protein composition, and antifungal activity.

Colleters are secretory structures well distributed in many organs of Angiosperms. Ultrastructurally, the colleters secretory cell presents an enhanced endoplasmic reticulum, Golgi apparatus, and mitochondria. Secretion synthesis, transportation, and passage through outer cell wall is poorly characterized. This study characterized the anatomy and ultrastructure of BATHYSA NICHOLSONII (Rubiaceae) colleters and evaluated the presence of protein in the secretion and its antifungal property. Samples were collected and prepared according to usual techniques in light and electron microscopy, electrophoresis, and fungal growth inhibition assay. Colleters are of a standard type, cylindrical and elongated, formed by one secretory epidermal palisade layer, and a central axis formed by parenchymatic cells and a vascular trace. Epidermal cells have dense cytoplasm with abundant ribosome, a nucleus, enhanced endoplasmic reticulum and Golgi apparatus. The outer cell wall presented morphologically distinct layers. The presence of secretory cavities was noted in all outer cell wall extents. Secretion preparations analyzed by SDS-PAGE showed that B. NICHOLSONII secretion is a mixture of proteins with molecular masses covering a range of approximately 66 to 24 kDa. This preparation presented an inhibitory effect on the fungi spore growth.

Antifungal Agents↗

PubMed2006

Methodological improvements on extraction of nuclear proteins and its preliminary analysis during the maize (Zea mays L.) endosperm development.

A procedure to obtain endosperm protein extracts was standardized. After confirming the enrichment with nuclear proteins by immunodetection, the protein profiles of extracts from different seed development stages were compared by SDS-PAGE that showed the existence of several differentially expressed proteins.

Electrophoresis, Polyacrylamide Gel↗

PubMed2003

Further morphological studies on the behavior of Trypanosoma rangeli in the hemocytes of Rhodnius prolixus.

The hemocytes of Rhodnius prolixus were analyzed during the course of infection with the protozoan Trypanosoma rangeli. The following cell types were identified: prohemocyte, plasmatocyte, adipocyte, granular cell and oenocytoid. The number of these cells changes during the infection course thus indicating a cell response to infection of R. prolixus by T. rangeli. Transmission electron microscopy showed that plasmatocytes were able to ingest epimastigote forms of the parasite, which were then found within a parasitophorous vacuole. Amorphous material was seen within the vacuole suggesting that fusion of host cell lysosomes with the vacuole took place. Intravacuolar parasites in process of digestion were observed. In addition, reaction product indicative of the presence of acid phosphatase was observed in parasite-containing vacuoles. No dividing parasites were seen within the vacuole in contrast to what was observed outside the host cells.

Animals↗

PubMed2001

Factorial design of electrolyte systems for the separation of fatty acids by capillary electrophoresis.

In this work, a capillary zone electrophoretic methodology using UV indirect detection (224 nm) for the analysis of fatty acids (FAs) in saponified oils is proposed. The electrolyte consisted of a 5 mmol l(-1) phosphate buffer, pH 7. containing 4 mmol l(-1) sodium dodecylbenzenesulfonate (SDBS) as chromophore, 4 mmol l(-1) dimethyl-beta-cyclodextrin and 45% acetonitrile (ACN). The composition of the electrolyte was optimized by a 2(3) factorial design with triplicate at the central point. The design established practical concentration boundaries for SDBS and ACN. In a defined concentration range of 2-4 l(-1), SDBS can certainly be used as a chromophore for indirect detection without imparting excessive baseline noise. For ACN, a suitable interval of 45-55% was found to enhance FAs solubilization without overflowing the system with bubble formation and current interruption. Additionally, the design revealed the importance of dimethyl-beta-cyclodextrin in the resolution of difficult pairs and its function as a solubilizing agent for long chain FAs. At the optimized conditions, nine FAs from C10 to C20, including mono- di- and tri-unsaturated C18 fatty acids were baseline separated in less than 10 min. The proposed method was applied to the separation of FAs in edible oils and polyunsaturated fatty acid enriched margarine. Additionally, spectral monitoring at 206 nm was used to confirm peak identity in the samples.

Electrolytes↗

PubMed2001

An electron microscopic study of penetration by Trypanosoma rangeli into midgut cells of Rhodnius prolixus.

The process of interaction of the Choachi strain of Trypanosoma rangeli with intestinal epithelial cells of Rhodnius prolixus was analyzed in experiments carried out in vitro and in vivo. For the in vitro experiments small fragments of the anterior region of the posterior midgut were incubated in the presence of the parasites, fixed, and processed for observation with the scanning electron microscope. Parasites attached to the surface of some epithelial cells, especially to the extracellular membrane layers (perimicrovillar membranes), were observed. For the in vivo experiments insects were infected with cultures of T. rangeli, sacrificed at different time intervals, and then processed for scanning and transmission electron microscopy. An intimate contact between the parasites and the membrane layers was observed. The parasites penetrated into cells that showed an electronlucent cytoplasm and a damaged surface, moved within the cytoplasm of the epithelial cell, reached the basal region, crossed the basal lamina, and entered the hemocoel.

Animals↗

PubMed2001

Interaction of Trypanosoma rangeli Tejera, 1920 with different cell lines in vitro.

Intracellular multiplication of Trypanosoma rangeli was evaluated in vitro using experimental infection of Vero cells, murine macrophages, and promonocytes with T. rangeli Choachi, Macias, and SC-58 clone B1 strains. Our results revealed a low infectivity of all T. rangeli strains to these cell lines. Macrophages showed the highest infection rate; however, intracellular forms were no longer observed 48 h post infection Despite the observation of intracellular parasites up to 144 h post infection, the infection rates of Vero cells and J774G.8 promonocytes with these parasite strains were always below 5%. Pre-incubation of parasites with normal mouse serum increased the initial infectivity but not the time course of the infection. Under our experimental conditions, we did not observe any evidence of intracellular multiplication of T. rangeli within these cell lines.

Animals↗

PubMed2001

[Possibilities and limits of epidemiologic surveillance at the local level towards health surveillance].

The aim of this study is to describe and analyze Epidemiological Surveillance activities (ES) developed in a Health Care Unit and to identify their adherence to recommended Health Surveillance (HS) strategies. A checklist with the activities recommended by the Ministry of Health was used to conduct interviews with health professionals involved in ES activities. The data obtained from these interviews showed that Epidemiological Surveillance activities are limited to the notification and control of infectious diseases, and the nurses' labor is characterized by bureaucratic tasks. This shows that further discussion about Health Surveillance strategies is necessary to find ways to better implement them in health services.

Brazil↗

PubMed1999

Evaluation of an educational programme for socially deprived asthma patients.

The aim of this study was to evaluate the effectiveness of an asthma education programme in moderate and severe asthma patients in a longitudinal, prospective and randomized study with a control group. Fifty-three asthmatic patients were studied, 26 of whom were assigned to the educational group and 27 to the control group. The educational group attended the programme regularly for a period of 6 months. The programme included information about asthma, instruction on the appropriate use of medication and training in the metered dose inhaler (MDI) technique, and information about the identification and control of asthma attacks and the recognition of early signs of exacerbation. The control group was submitted to the routine care provided at the Asthma Clinic, with no formal instruction regarding asthma control. The groups were identical with regard to severity parameters, skills, lung function and quality of life at the beginning of the trial. At the end of the study, the education group showed significant differences when compared with the control group (education/control (mean values)) with respect to: visits to the asthma emergency room over the previous 6 months, 0.7/2 (p=0.03); nocturnal symptoms, 0.3/0.7 (p=0.04); score of symptoms, 1.3/2 (p=0.04). Improvements were also observed in skills and quality of life, knowledge of how to deal with attacks and how to control the environmental triggering factors, 73/35 (<0.05); correct use of the MDI, 8/4 (0.001); understanding of the difference between relief and anti-inflammatory medication, 86/20 (<0.05); and in the global limitation quality of life score, 28/50 (0.02). It is concluded that the educational programme led to a significant improvement in asthma morbidity and that the implantation of educational programmes is possible for special populations when these programmes are adapted to the socioeconomic profile of the patients, with a significant gain in terms of the reduction of symptoms and improved pulmonary function and quality of life of asthmatics.

Adult↗

PubMed1997

[Persistent trigeminal artery associated with aneurysm of the middle cerebral artery. Case report and review of the literature].

The authors report a case of persistent primitive trigeminal artery angiographically demonstrated as an incidental finding. The persistent primitive trigeminal artery was associated with an aneurysm arising from the circle of Willis in the middle cerebral artery territory. The literature is reviewed and the embryology involved is related.

Carotid Arteries↗

PubMed1997

Evaluation of an educational program for asthma control in adults.

We have developed a 6-month educational plan associated with outpatient follow-up and special clinical care for asthmatic patients in a deprived population, with serious socioeconomic problems and a very low level of education. The objective was to determine the effects of the program on clinical asthma outcomes, lung function, and quality of life. Forty patients were enrolled in the program with a regular schedule of outpatient visits, and 31 finished the 6-month intervention, which included information about asthma, instruction in appropriate use of medication, training in metered-dose inhaler technique, how to identify and control asthma triggers, how to use symptom diary cards, and how to recognize early signs of deterioration. Patients included 8 males and 23 females, 47.8 +/- 16.5 years old, with 77.4% elementary school education and 22.6% illiterate, and an average monthly income of around $450. After the 6-month program there was a significant change in asthma control with a reduction in asthma emergency visits and hospitalization, reduction of score symptoms, and improvement in quality of life. Based on the results, educational programs are recommended and should be adapted to the socioeconomic and cultural characteristics of the target population.

Administration, Inhalation↗

PubMed1993

[Sporadic amyotrophic lateral sclerosis. Diagnostic criteria].

The authors report two cases of amyotrophic lateral sclerosis (ALS) misdiagnosis (a craniocervical junction disorder, and a cervical spinal cord ependymoma). They review some causes of ALS-like syndrome and propose a protocol to be adopted for the study of all patients who present clinical abnormalities suggesting ALS.

Adult↗

PubMed1993

Cephalometric standards for white Brazilians.

Lateral cephalometric radiographs were obtained from 30 individuals that were equally divided into groups by gender. Their ages varied from 18 to 31 years. All were white Brazilians with normal dental occlusions and good facial profiles. A combination of angles and linear measurements from Steiner's and Downs' analyses were determined. Means and standard deviations were calculated for the sample. Student's t test did not show a statistically significant difference between men and women. The entire sample was compared with the North American standards reported by Steiner and Downs. Statistically significant differences were found for GoGn/SN and SND angles. The statistically greater values of 1/NA(mm), 1/NB(mm), and 1/NA(degrees) for the Brazilians indicate typical morphological aspects with protrusive incisors. These differences and the great variation within the sample should be taken into account when formulating an orthodontic treatment plan for Brazilians.

Adolescent↗

PubMed1992

[The human attitude in a situation facing death].

The present paper was produced in order to help students, to deal with the death situation. It focus on concepts and conflicts related to terminal stage, death and post-death period, which demands attitudes of involvement of the professional in this situation, and other complementary informations about the whole issue.

Attitude to Death↗

PubMed1990

Comparison of the effect of endothelin on microvessels and macrovessels in Goldblatt II and deoxycorticosterone acetate-salt hypertensive rats.

The response to endothelin, a novel 21-amino acid peptide, is investigated in isolated aortas with and without endothelium and in mesenteric microvessels in vivo-in situ, in Goldblatt II (GII) and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Median effective concentrations and maximal responses to endothelin did not differ in aortas with endothelium isolated from GII, DOCA-salt hypertensive, and control rats. After removal of the endothelium, the potentiation of the aorta responses to endothelin was of the same magnitude in hypertensive and control rats. A closed-circuit television system was used to observe the microvascular bed of the exteriorized mesentery of anesthetized GII, DOCA-salt hypertensive, and control rats. The time necessary to induce a vasoconstrictor response was determined after the topical application of endothelin. Vessel diameters at rest and after endothelin application were also estimated. At the microcirculatory level, a greater reactivity to endothelin was observed in both hypertensive rat groups, whereas higher sensitivity to endothelin was recorded in the GII hypertensive microvessel preparations alone. It is suggested that the increased response to endothelin observed in hypertensive rats might be due to abnormal sensitivity or reactivity of the microvessels of these rats reflecting an alteration of the contractile sequence possibly at the plasma membrane level, or due to both. Endothelial dysfunction at the microcirculatory level, however, cannot be dismissed.

Animals↗

PubMed1984