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Biomedical subjects

M F Ferreira

Publications and source records attributed to M F Ferreira.

14 recordsLinked to original sources
PubMed2003

Activity of essential oils from Mediterranean Lamiaceae species against food spoilage yeasts.

The essential oils from aerial parts of Melissa officinalis, Lavandula angustifolia, Salvia officinalis, and Mentha piperita were analyzed by gas chromatography and gas chromatography-mass spectrometry. Their antimicrobial activities were evaluated against five food spoilage yeasts, Torulaspora delbrueckii, Zygosaccharomyces bailii, Pichia membranifaciens, Dekkera anomala, and Yarrowia lipolytica. Saccharomyces cerevisiae was also used as a reference. The oils were preliminarily screened by a disc diffusion technique, with the most active being the oil from M. officinalis. MICs were determined by the broth dilution method, and the main components of the oils were also tested by this method. The essential oil of M. officinalis at 500 microg/ml completely inhibited the growth of all yeast species. The main component of the oil of M. officinalis is citral (neral plus geranial) (58.3%), which showed a marked fungitoxic effect, contributing to its high activity.

Anti-Infective Agents↗
PubMed2000

Dbf4p, an essential S phase-promoting factor, is targeted for degradation by the anaphase-promoting complex.

The Dbf4p/Cdc7p protein kinase is essential for the activation of replication origins during S phase. The catalytic subunit, Cdc7p, is present at constant levels throughout the cell cycle. In contrast, we show here that the levels of the regulatory subunit, Dbf4p, oscillate during the cell cycle. Dbf4p is absent from cells during G(1) and accumulates during the S and G(2) phases. Dbf4p is rapidly degraded at the time of chromosome segregation and remains highly unstable during pre-Start G(1) phase. The rapid degradation of Dbf4p during G(1) requires a functional anaphase-promoting complex (APC). Mutation of a sequence in the N terminus of Dbf4p which resembles the cyclin destruction box eliminates this APC-dependent degradation of Dbf4p. We suggest that the coupling of Dbf4p degradation to chromosome separation may play a redundant role in ensuring that prereplicative complexes, which assemble after chromosome segregation, do not immediately refire.

Anaphase↗
PubMed2000

Cholinesterase activities determination in frozen blood samples: an improvement to the occupational monitoring in developing countries.

1. Studies were carried out on rural workers in Brazil to determine the decrease in the activity of plasma butyrylcholinesterase (BChE), erythrocyte cholinesterase (AChE) associated with exposure to organophosphorus pesticides (OP). The goal of this work is to help prevent injury to these workers. 2. In developing countries the distance between area of pesticide use and reference laboratories is a drawback for analytical techniques, since cholinesterase activity determinations require fresh blood samples. Field methodologies can be a useful alternative to laboratory tests, however they are not as sensitive as those found in laboratories. 3. The modification of Ellman's Method presented in this paper allows blood samples to be frozen and maintain enzymatic stability: 7 days for AChE and 3 days for BChE. The proposed method is also more sensitive than Ellman's Method Modified by Magnotti (EMMM). 4. The results suggest that the Ellman Method Modified by Oliveira-Silva (EMMOS) is valid for monitoring procedures. This method represents an important contribution to the process of monitoring OP exposures, since the evaluations no longer have to be conducted near the site of OP use.

Acetylcholinesterase↗
PubMed1999

Spontaneously occurring anti-PTH autoantibodies must be considered in the differential diagnosis of patients with elevated serum PTH levels.

We investigated the cause of elevated immunoreactive circulating parathyroid hormone (PTH) levels in two females of 41 (case 1) and 39 (case 2) years of age with low/normal serum calcium levels and hypocalcemia, respectively, and, in the latter case, hyperprolactinemia. Serum samples from both patients were fractionated by Sephadex G-100 Superfine chromatography. Fractions were assayed for PTH and prolactin (PRL) by immunoradiometric assays (IRMA) and for immunoglobulin G (IgG) by radial immunodiffusion. Sera from both patients were incubated with protein A and protein G Sepharose, centrifugated and the supernatant was assayed for PTH by IRMA. Sera were also subjected to affinity chromatography with an anti-human-IgG-agarose column. IgG and PTH or PRL were measured in the fractions by radial immunodiffusion and IRMA, respectively. In both cases the majority of serum PTH immunoreactivity eluted in the same fractions of IgG after gel filtration and was precipitated by protein A (89% in patient 1 and 96% in patient 2) and protein G (83% in patient 1 and 100% in patient 2), thus, behaving as IgG. In case 1, 79% of PTH was also retained by an anti-hIgG agarose column. High PRL levels in patient 2 were due to macroprolactinemia since most of PRL eluted as big,big (40%) and big-PRL (45%) after gel filtration. Forty-eight percent of PRL from patient 2 was retained by the anti-hIgG column indicating the presence of an anti-PRL autoantibody. These data suggest that spontaneously occurring anti-PTH autoantibodies must be considered in the differential diagnosis of patients with elevated serum PTH levels.

Adult↗
PubMed1998

Rapid weight gain, at least in some women, is an expression of a neuroendocrine state characterized by reduced hypothalamic dopaminergic tone.

A group of 17 consecutive regularly menstruating women who gained at least 5 kg the previous year (Group 1) was compared with a control group of similar age, parity and social class (Group 2). Galactorrhea was observed in 6/17 women from group 1 and in 1/16 women from group 2 (chi 2 4.571; p < .05). Average morning prolactin levels were higher in group 1 (8.15 +/- 4.92 micrograms/l) than in group 2 (5.29 +/- 2.48 micrograms/l; p < .05). The two groups were similar in their morning thyroxin, triiodothyronine, TSH, estradiol, cortisol, gastrin, cholecystokinin, somatostatin, oxytocin, insulin and IGF-1 levels. Leptin levels were significantly higher in group 1 than in group 2 (18.85 +/- 10.63 micrograms/l vs. 10.15 +/- 6.38 micrograms/l; p < .02) but this difference could be attributed exclusively to the higher body mass index (BMI) of group 1 (MANCOVA). Analysis of the distribution of basal prolactin levels in group 1 revealed a skewed distribution due to the presence of six outliers (Barnett and Lewis test associated with Mahalanobis distance) whose values were higher than the highest value found in group 2. These outliers were henceforth considered as subgroup 1a, and the remnant patients in group 1 as subgroup 1b. Besides the expected difference in basal prolactin levels between subgroups 1a and 1b (13.72 +/- 3.69 and 5.12 +/- 1.81 micrograms/l, respectively) and the higher frequency of galactorrhea in group 1a (4/6 vs. 2/11; p < .05) no other differences were observed in clinical or basal biochemical parameters. Following domperidone (10 mg, i.v.) the percentual increase in prolactin (delta Prl 20'/Prl 0') was significantly lower in group 1 than in group 2 (23.9 + 15.2 vs. 37.0 +/- 21.2; p < .05). In absolute values, the prolactin rise in subgroup 1a (100.7 +/- 45.5 micrograms/l) was significantly lower (p < .02) than that of subgroup 1b (157.3 +/- 50.3 micrograms/l) and group 2 (152.7 +/- 34.5 micrograms/l). Group 1 (and each one of its two sub-groups) also differed from group 2 in a higher incidence of meaningful life-events the year preceding the study. This study confirms previous observations that recent weight gain in women is preceded by important life-events and is associated with galactorrhea and increased prolactin levels in a number of them. Besides, it provides evidence that the increased prolactin levels are due to reduced hypothalamic dopaminergic tone.

Adult↗
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↗
PubMed1995

Endocrine and psychological evaluation of women with recent weight gain.

A group of 13 consecutive regularly menstruating women who gained at least 5 kg the previous year (Group I) was compared to a control group of similar age, parity, and social class (Group II). The two groups were similar in estimated and observed food intakes; pre- and postprandial gastrin levels; hourly 24-h profiles of cortisol and insulin; urinary cortisol and 17-hydroxycorticosteroids. Group I had higher serum prolactin concentrations at all times than Group II (mean values 14.60 micrograms/l vs. 8.84 micrograms/l; p = .0121). Galactorrhea was observed in 5 women from Group I and in none of the women from Group II (p < .05). Group I also differed from Group II in a higher incidence of meaningful life-events the year preceding the study, higher prevalence of sexual dysfunction (9/13 vs. 4/13; p < .01) and higher indexes (p < .05) of several parameters in the MMPI and SCL 90. Median serum cortisol and prolactin concentrations were negatively correlated, both in Group I (R = -.669; p = .012) and in the whole sample (R = -.453; p = .0298). It is suggested that the rapid weight gain is part of a neuroendocrine response to environmental stimuli also characterized by hyperprolactinemia. The significant negative correlation between serum prolactin and cortisol indicates that this response differs from, and is possibly an alternative to, the sympathoadrenal "stress" response.

Adult↗
PubMed1990

[Intestinal myiasis in Macao].

Six cases of intestinal myiasis were diagnosed in Macao from January 1987 to August 1989, during a survey of intestinal parasites in inhabitants and on stool routine examination in hospitalized patients. The species of flies identified were Stomoxys calcitrans in 4 cases and Megalesia (Megalesia) insulana in 2 cases, M. insulana being a new record in mainland of China. During the survey of intestinal parasites 1889 human fecal samples were collected from Chinese inhabitants. 45 samples were collected on September 2 and 15 samples on September 11, 1987 in an aged home. Among them 4 samples were found to have some moving larvae, which were later identified morphologically as S. calcitrans. All these four cases were old ladies living in the aged home and they complained of mild diarrhea and abdominal pain. The fifth case was a patient with dermatosis, who had an eosinophil count of 18%. On stool examination, eggs of Clonorchis sinensis and larvae of flies were found. These larvae were cultured in food stuff containing wheat bran (100g), milk powder (18g) and water (200ml) at 30 degrees C. Within a week these larvae became pupa from which hatched adult flies identified as M. insulana which were known to be distributed in the Philippines and Hawaii but not found in the mainland of China before. 3 months later the stool from the patient was re-examined, about 200 larvae were counted in 5 ml of feces, the fly species being the same. The sixth patient was a pediatric case, again in his stool sample larvae of flies were found which were identified as M. insulana after culture. M. insulana is distributed in the Philippines, Hawaii, etc. Since a great amount of fruits was constantly imported from the Philippines and Hawaii, it remains to be confirmed whether M. insulana is imported into Macao through fruits.

Aged↗
PubMed1985

Double infection of the CNS with herpes simplex and mumps viruses. Serological and ultrastructural studies.

Clinical, serological and ultrastructural features are described in a case of acute encephalitis. The ultrastructural study of brain biopsy specimens revealed herpes-and paramyxovirus-like particles in neurons and glial cells that were characterized as herpes simplex and mumps viruses by serological study in serum and CSF. Of the few cases previously reported with double encephalitis, this is the only one in which ultrastructural and serological evidence of combined brain infection has been found.

Antibodies, Viral↗
PubMed1983

Cytosolic malate dehydrogenase in muscle extracts of Toxocara canis.

1. Malate dehydrogenase (L-malic acid:NAD+ oxydoreductase, EC 1.1.1.37) was partially purified from muscle extracts of Toxocara canis by means of gel chromatography in Sephadex G-150 and affinity chromatography in Sepharose-4B-Blue dextran. 2. The purified enzyme was very active in reducing oxalacetate and less active in oxidizing L-malate. It was inhibited by excess oxalacetate but not by L-malate. 3. The kinetic parameters of the enzyme were obtained and these included: pH and temperature optima and apparent Michaelis constants for the substrates. 4. The results suggest that the enzyme from Toxocara canis behaves like the enzyme of the model helminth Ascaris lumbricoides.

Animals↗
PubMedDate not supplied

The influence of humidity on the residual action of benzene hexachloride (BHC).

In controlled humidity chambers in the laboratory differences in the absorption velocity of BHC were observed depending on the substrate sprayed. While BHC is no longer used in Chagas' disease control this data could have relevance to spraying houses in a control programme with other insecticides.

Hexachlorocyclohexane↗
PubMedDate not supplied

The influence of building materials on the residual action of BHC.

Residual insecticide activity of BHC vapors from various building materials in controlled humidity chambers in the laboratory were significantly different. Laboratory-reared, first instar nymphs of Dipetalogaster maximus were exposed to vapors of BHC which were being released from the treated surfaces of building materials taken from Mambaí, Goiás.

Animals↗
PubMedDate not supplied

Nasal provocation tests in the diagnosis of urticaria induced by acetylsalicylic acid.

Nasal provocation tests with lysine acetylsalicylic acid (ASA) have been used in the diagnosis of ASA-induced asthma and rhinitis. To establish its possible role in identifying aspirin sensitivity manifested by urticaria or angioedema, 18 patients suffering from chronic or acute recurring urticaria/angioedema (10 ASA-sensitive and 8 ASA-nonsensitive) were submitted to nasal provocation tests with freshly prepared solutions of lysine ASA. Clinical response and variation of nasal expiratory peak-flow were evaluated, classified according to previously defined scores, and compared. The results showed a significant difference between ASA-sensitive and ASA-nonsensitive patients, suggesting that this test can be an important diagnostic tool for ASA-induced urticaria/angioedema.

Adolescent↗