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M F Dias

Publications and source records attributed to M F Dias.

7 recordsLinked to original sources
PubMed2000

The role of HLA antigens in the development of paracoccidioidomycosis.

BACKGROUND: Paracoccidioidomycosis is a systemic granulomatous disease that involves primarily the lungs and may disseminate to other organs and systems. It is caused by Paracoccidioides brasiliensis, a fungus that exhibits reversible thermal dimorphism and whose natural habitat is presently unknown. There are two main clinical forms: the acute (subacute) juvenile form and the chronic adult form. The former runs a more rapid course and is more severe than the latter. This mycosis is found throughout Latin America. Brazil accounts for 80% of reported cases. Presumably P. brasiliensis thrives in humid and hot places, especially near forests or farms. The infection is endemic in certain areas, especially in Brazil, Colombia and Venezuela, where nearly 100% of the population show cutaneous paracoccidioidina positive skin tests, indicating previous contact with the fungus, although a small percentage show clinical manifestations of the disease. METHODS: We compared the expression of HLA class I antigens in a healthy group (control) and in a group of patients with paracoccidioidomycosis (chronic adult form) using the Terasaki lymphocytotoxicity test modified by Amos for HLA antigen analysis. AIMS: To discover indications of whether or not individual susceptibility to P. brasiliensis might depend on some specific immunological defect. RESULTS: There is no evidence of association between a specific HLA antigen and paracoccidioidomycosis in the subjects studied. Further investigations are recommended.

Adult↗
PubMed1997

[Comparative study of benign and malignant tumor of the ovary].

This study concerns the evaluation of epidemiologic, clinical and laboratory parameters and the comparison of the multiple parameters between benign and malignant tumors of the ovary to establish significant criteria allowing a Malignant Risk Index to be defined. The incidence of ovarian cancer was higher among post-menopausal women with no use of oral contraceptives. There was no correlation between sterility, infertility or nulliparity and ovarian cancer. The age at menarche, menopause or first term delivery showed no influence on the risk of ovarian cancer. The Authors verified significant differences (p < 0.001) in the levels of serum CA 125 between patients with benign ovarian tumors and patients with ovarian cancer. Those differences showed high sensitivity and specificity. Ultrasonographic criteria were difficult to interpret because of their subjectivity. However, there were significant differences concerning the size of the tumors, the bilaterality, the solid component and ascites; all these criteria were more frequent among malignant masses. It is imperative to define a high confidence degree Malignant Risk Index for ovarian tumors allowing the establishment of screening strategies applicable to risk populations.

Adolescent↗
PubMed1996

Pharmacological characterization of Sephadex-induced oedema in rat paws: predominant role of serotonin and platelet-activating factor.

An intravenous injection of Sephadex beads has been used to induce lung inflammation and bronchial hyperreactivity in small animals. In the present study, we injected Sephadex beads (0.3-5.5 mg/paw) into rat paws and followed the resulting inflammation plethysmometrically. Our results show that Sephadex beads induced a significant and dose-dependent increase in the hindpaw volume at 5 min; it was maximal at 30-60 min and declined at 4 h. However, the paw volume remained significantly increased for up to 21 days. The initial 4-hour-oedema was confirmed by histopathology of the paw tissues, but the persistent increase in paw volume was related to a chronic inflammatory (granulomatous) response. The Sephadex-induced oedema was predominantly due to serotonin (5-HT) release since specific antagonists such as methysergide (1 mg/kg) and pizotifen (0.1-2 mg/kg) administered both systemically and locally were able to inhibit the oedema (10-100 microgram/paw) as could pretreatment with compound 48/80. In addition, platelet-activating factor (PAF) was also shown to be involved, since systemic pretreatment using the specific PAF antagonist BN 52021 (1 mg/kg) was able to inhibit the increase in paw volume induced by Sephadex. Effective doses of indomethacin (2 mg/kg), L-NAME (1 mg/kg), pyrilamine (1-2 mg/kg), ondansetron (1 mg/kg) and HOE 140 (1 mg/kg) did not affect the Sephadex-induced oedema, thus ruling out the participation of prostaglandins, nitric oxide, histamine, 5-HT3 receptors and bradykinin in its development. Since the late increases in paw volume induced by Sephadex were reduced by pretreatment of the animals with the immunosuppressive drugs rapamycin and dexamethasone but not cyclosporin, our results also suggested that distinct immunological pathways may be involved in the modulation of the chronic phase of inflammation induced by Sephadex beads in rat paws.

Animals↗
PubMed1987

A test for the evaluation of ingestion by neutrophils.

A rapid, simple and inexpensive technique was developed to evaluate particle ingestion by neutrophils (PMNs) and alternatively investigate the activity of the complement system. Whole blood specimens, obtained in EDTA, were mixed with a suspension of activated Baker's yeast in minimal volumes (3 and 1 drops of each, respectively). The mixture was incubated at 37 degrees C for 1 h and centrifuged at 200 g for 5 min. The sediment was resuspended in FBS and blood films were stained with Giemsa. Two hundred PMNs/film were counted and the percentage of phagocytizing cells and the mean number of ingested particles per cell were determined. Samples from 11 male and 15 female subjects showed mean rates of 80.0 +/- 10.8 (SD) and 83.3 +/- 5.8 of PMNs with phagocytic vacuoles containing 2.9 +/- 0.5 and 3.2 +/- 0.7 ingested particles/cell, respectively. There were no statistically significant differences between sexes.

Female↗
PubMedDate not supplied

[Mycetoma due to Actinomadura madurae. A report of 2 cases].

Actinomadura madurae mycetoma was diagnosed in two patients by the dermatologic outpatient clinic of the Clementino Fraga Filho University Hospital (UFRJ) and the Antonio Pedro University Hospital (UFF). The first case was a 27-year-old Negro male from the outskirts of Rio de Janeiro, who was injured prior to the onset of the disease in 1988. The affected left foot showed swelling, nodules, sinus tracts, purulent discharge containing grains, and serious bone involvement with lytic lesions. Histological examination showed deeply basophilic stained grains with typical wide-fringed borders. The mycological examination revealed an actinomycete identified as A. madurae by culture. Oral tetracycline for six months did not improve the clinical-radiological picture and the patient was submitted to amputation. The second case was a 70-year-old white male, with previous injury in 1974, which occurred in Pernambuco State. Enlargement of the right foot draining sinuses formation with discharge of pus and grains. In tissue sections the grains were large and surrounded by amorphous eosinophilic clubs radially oriented. There was discrete improvement by tetracycline and sulfonamide. No follow-up.

Adult↗