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M M Vilela

Publications and source records attributed to M M Vilela.

At least 19 recordsLinked to original sources
PubMed2003

Defective Fc-, CR1- and CR3-mediated monocyte phagocytosis and chemotaxis in common variable immunodeficiency and X-linked agammaglobulinemia patients.

Blood monocyte phagocytic functions were evaluated by chemotaxis, phagocytosis, and superoxide anion production in nine patients with common variable immunodeficiency (CVI), eight patients with X-linked agammaglobulinemia (XLA), and in 17 normal subjects. Further laboratory diagnosis included the determination of the Bruton's tyrosine kinase (Btk) protein expression in monocytes using flow cytometry. The analysis of monocyte phagocytic function demonstrated that CR3-, CR1-, and Fc-mediated phagocytosis (p = 0.0001) were significantly decreased in CVI and XLA patients, and chemotaxis of monocytes (p = 0.0082) was reduced in XLA patients. Superoxide anion production, however, did not differ between the CVI, XLA, and the control groups. The cytoplasmic expression of Btk protein in monocytes was normal in CVI patients and decreased or not detected in XLA patients. It is proposed that impaired chemotaxis and phagocytosis by monocytes may be a characteristic of the innate immune system in CVI and XLA patients, providing a new direction for the physiopathology of these immunodeficiencies.

Adolescent↗
PubMed2000

Evolution of nutritional status of infants infected with the human immunodeficiency virus.

CONTEXT: There are today only a limited number of studies defining growth parameters and nutritional status for HIV children. OBJECTIVE: To study the nutritional status of infants infected with the human immunodeficiency virus. TYPE OF STUDY: Longitudinal study. SETTING: Department of Pediatrics, Faculty of Medical Sciences, UNICAMP, Campinas, Brazil. PARTICIPANTS: One hundred and twenty-four children born to HIV infected mothers were evaluated from birth until the age of two years. They were subdivided into two groups: 71 infected children and 53 non-infected children. MAIN MEASUREMENTS: Growth was evaluated in both groups by comparing Z-scores for weight/age (w/a), length/age (H/a) and weight/length (w/H) (using the NCHS curves as reference). RESULTS: The Z-score analyses showed that there was a significant difference between the two groups for all the variables studied, except for the H/a value at 3 months of age and the W/H value at 21 months of age, which showed P > 0.05. CONCLUSIONS: The growth of infected infants was observed to be severely affected in comparison with that of seroreversed infants in the same age groups. Although clinical manifestations may take time to appear, the onset of growth changes begin soon after birth.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Isolation of Candida dubliniensis from the oral cavity of an HIV-positive child in Brazil.

Candida dubliniensis is a newly-recognized Candida species and an important infectious pathogen, particularly for HIV-positive patients. >From oral smear samples from the radix linguae of 173 HIV-positive children, we obtained four yeast isolates which took a blue-green color on CHROMagar Candida plate at 37 degrees C for 48 hours from one HIV-positive 3-year-old boy in Brazil. The isolates were difficult to grow on potato dextrose agar plate at 42 degrees C, produced abundant chlamydospores on a cornmeal agar plate with Tween 80, and sprouted germ tubes in saline with horse serum, and the antigenic profile by CANDIDA CHECK test was useless. Carbohydrate assimilation tests by ID32C showed no reference code number in the reference book. The isolates were subjected to molecular biological assay of the DNA sequence of the large-subunit ribosomal DNA region (D1/D2) and randomly amplified polymorphic DNA (RAPD). The DNA sequence agreed with those of standard C. dubliniensis strains, and therefore, the isolates were identified as C. dubliniensis. RAPD band pattern analysis indicated that the clinical isolates might summarize one genotype. Although the child did not present oral lesions, the fungus might be latent for opportunistic infection.

Brazil↗
PubMed1997

Complement factor I deficiency in a family with recurrent infections.

Factor I deficiency causes a permanent, uncontrolled activation of the alternative pathway resulting in an increased turnover of C3 and consumption of factor B, factor H and properdin. Factor I deficiency is clinically associated with recurrent bacterial infections already in early infancy, mainly affecting the upper and lower respiratory tract, or presenting as meningitis or septicemia. We here report on a Brazilian family (n = 9) with known consanguinity, where in 3/7 children, suffering from chronic otitis, meningitis, and respiratory infections, a complete factor I deficiency was recognized. One of the patients died after fulminant sepsis. Hemolytic activity of the alternative pathway was not detectable in the patients' sera due to decreased plasma concentrations of C3, factor B and properdin. As a consequence of factor I deficiency, C3b could not be metabolized with the result that no C3-derived split products (C3dg/C3d) were detectable in the patients' sera. In vitro reconstitution with purified factor I restored the regulatory function in the patients' sera with the subsequent cleavage of C3b to C3c and C3dg. Factor H levels were decreased in all patients' sera and found to be tightly complexed with C3b resulting in a modified electrophoretic mobility. Upon factor I reconstitution, factor H was released from C3b regaining its beta 1 electrophoretic mobility. Complement-mediated biological functions like opsonization of bacteria, chemotactic activity and phagocytosis in these patients were impaired. The parents (cousins, 2nd degree) and 3/4 siblings had significantly reduced factor I plasma levels without further alteration in their complement profile. 3 of these obviously heterozygously deficient family members suffered from recurrent bacterial infections of different frequency and severity.

Adolescent↗
PubMed1994

Congruence of the topography of intracranial calcifications and epileptic foci.

Nodular intracranial calcifications (NIC) are frequent findings in CT scans of epileptic patients in countries where granulomatous central nervous disease such as neurocysticercosis is endemic. In 34 consecutive epileptic patients with NIC submitted to EEG, CT and CSF analysis, the correlation between the electroclinical localization of the focus and the topography of the NIC was studied. Twenty-nine patients had partial (Group I) and 5 had primarily generalized seizures (Group II). Twenty group I and 1 group II patients showed abnormal EEGs. CSF abnormalities consisted of increased protein content (n = 3) and positive Weinberg's reaction (n = 2). In 2 cases, viable neurocysticercotic vesicles were seen. Twenty-one patients had single NICs. No correlation could be established in group II patients. Within group I, 15 patients had a positive and 14 a negative correlation. Sixty-six percent of the patients with single NICs had negative correlations. These findings strongly suggest that the calcifications themselves are not the epileptogenic lesions in at least 50% of the studied cases.

Adolescent↗
PubMed1991

Theophylline therapy inhibits neutrophil and mononuclear cell chemotaxis from chronic asthmatic children.

1. Theophylline is commonly used to relieve symptoms of chronic asthma. Since neutrophil and mononuclear cell activation are associated with late phase asthmatic reactions, effects of theophylline on these cells may be of importance. 2. In the present investigation we compared neutrophil and mononuclear cell chemotaxis from chronic asthmatic children during and after theophylline therapy. 3. Thirty patients were recruited for the study. Each patient received theophylline orally for 10 days. The theophylline dose was 20 mg kg-1 day-1 given in four divided doses. On the tenth day, blood was collected into heparinized (100 u ml-1) and siliconized tubes 2 h after the last theophylline dose for chemotactic assays, cAMP and theophylline plasma determinations. When clinical conditions allowed, theophylline was discontinued for 7 days and the chemotactic assays, cAMP and theophylline plasma concentrations repeated. Serum complement and IgE levels were also determined. 4. Theophylline therapy clearly inhibited both spontaneous and stimulated neutrophil and mononuclear cell chemotaxis. Twenty-seven patients had therapeutic plasma concentrations of theophylline (5-20 micrograms ml-1). Discontinuation of theophylline therapy caused a significant decrease in plasma cAMP levels (44 and 31 pmol ml-1 respectively during and after treatment, n = 30, P less than 0.001). 5. The inhibition of neutrophil and mononuclear cell migration by theophylline therapy in chronic asthmatic children may be beneficial for the control of the inflammatory response observed in these patients.

Asthma↗
PubMed1991

Eating epilepsy.

Eating epilepsy is a rare type of reflex epilepsy. A 24 years-old male with eating reflex complex partial seizures was submitted to clinical, neurological, neuroradiological and EEG studies. Neurologic and CT examinations were normal. EEG recordings including video-EEG monitoring during meals disclosed focal abnormalities related to both temporal lobes prevailing at the left side and secondary bilateral synchrony mainly in more anterior regions. Ictal findings were similar to the interictal secondary bilateral synchrony except for its longer duration. PB, VPA and DPH monotherapies were ineffective. High dose CBZ monotherapy yielded good but incomplete seizure control. Since a big number of precipitants could be involved, no specific physiopathological basis could be established.

Adult↗
PubMed1990

Mental deterioration in Lafora's disease.

Lafora's disease is included among the progressive myoclonic epilepsies. Despite the fact that dementia is a constant finding in this disease only a few papers have studied the timing of mental deterioration. We have performed wide neuropsychological testing in two cases early diagnosed as Lafora disease. The initial neuropsychological testing was carried out by the time there were no complaints of mental deterioration in both cases. In the first case consecutive neuropsychological testing demonstrated the rapidly progressive dementia. All neuropsychological testings in these cases showed severe impairment of right parietal lobe functions. Higher cortical functions related to language and intellectual processes were best preserved in both cases. The functions related to constructional praxis, memory and abstract concepts and processes were severely impaired. Our data suggest that mental deterioration is an early manifestation in Lafora disease, even by the time normal social life is not yet disturbed. Dominant hemisphere cognitive functions have been less impaired than the non-dominant ones. How a diffuse illness such as Lafora disease can cause such an asymmetrical higher cortical function deficit is not yet clear.

Adolescent↗
PubMed1989

Non-epileptic myoclonus and mitochondrial encephalomyopathy.

Two brothers presented to us with a progressive myoclonic syndrome with slight cerebellar symptoms. Neurological examination disclosed moderate cerebellar signs and pale optic discs; asymmetric, asynchronous and arrhythmic myoclonus, an arrthesthesic deficit and no muscular weakness. EEG background activity was moderately slow with no irritative discharges. CT was normal in both cases. Intermittent photic stimulation increased the frequency of the myoclonic jerks, which became bilateral and synchronous, progressing to a generalized tonic-clonic seizure. EPs and MRI in one case were normal. Anticonvulsant drugs were ineffective. The diagnosis of mitochondrial encephalomyopathy was based on the finding, in muscle specimens, of thickened basement membranes with myofibrillary degeneration and increased number of mitochondria peripherally distributed and with a dense granular matrix and some vacuoles. The clinical and EEG data suggest a subcortical origin for this type of myoclonic syndrome.

Adult↗
PubMed1989

Reduced phagocytic activity mediated by C3b and Fc monocyte receptors from children with sickle-cell disease.

The causes of high morbidity due to infection among children with sickle-cell disease (SD) are unknown. Immunological studies have focused on spleen function, on the alternative complement pathway, and recently on phagocytic activity. We evaluated Fc receptor-mediated phagocytosis (sheep red cells opsonized with rabbit anti-E IgG, EA) and C3b receptor-mediated phagocytosis (zymosan particles incubated with fresh serum) in 27 children with SD. The control group consisted of 28 normal children matched by age and sex. The phagocytic indices obtained for cells from patients with SD were significantly lower than those for the controls (P less than 0.001), both when EA and zymosan were used and independent of whether the zymosan particles were incubated with patient serum or with a pool of normal sera. The results suggest the absence of abnormalities in the alternative complement pathway but do indicate an intrinsic cellular defect.

Adolescent↗
PubMed1988

Inherited C3 deficiency of the complement system.

1. We report a patient homozygous for C3 deficiency and several heterozygotes from the same family. Upon follow-up, the homozygote was found to suffer several severe bacterial infections, whereas all the heterozygotes were clinically healthy. 2. C3 was undetectable in the homozygous patient, CH50 was very low and factor I was present. Serum capacity to generate chemoattractant stimuli for peripheral leucocytes was similar to that of normal adults as was also observed for one of the heterozygotes. Serum capacity to opsonize yeast was reduced in the presence of autologous and homologous (normal adult) cells. The CH50 levels of heterozygous patients were within the lower range of normality. 3. The parental consanguinity and the homozygosis state observed here are classical signs of recessive autosomal inheritance. However, the lower or below normal C3 levels detected in parents and relatives point to a co-dominant inheritance of gene S with respect to the "null" gene. 4. C3 polymorphism presented a predominantly "slow" pattern in most family members, which, together with the low C3 levels, indicates the expression of S-allotypes.

Antibodies, Anti-Idiotypic↗
PubMed1981

Chronic Chagas' disease: unimpaired delayed type hypersensitivity reactions in contrast with humoral suppression to typhoid vaccine.

Peripheral T and B cells were decreased in patients chronically infected with Trypanosome cruzi. The humoral response to Typhoid vaccine was suppressed in contrast with normal cutaneous delayed type hypersensitivity (DTH) reactions to Candida antigen, P.P.D., SK-SD, Vaccinia Virus antigen and DNCB. Complement and lg levels were between normal range and no immune complexes were detected by precipitation with polyethylene glycol.

Adolescent↗
PubMedDate not supplied

[Serum immunoglobulins in children perinatally exposed to human immunodeficiency virus]

OBJECTIVE: Hypergammaglobulinemia is an early manifestation of perinatal HIV infection. Our objective was to analyze the differences in serum immunoglobulin levels between infected and seroreverter children and their association with clinical outcome. METHODS: We carried out a historical prospective study with 107 infected and 90 seroreverter children. We compared the IgA, IgG, and IgM levels between infected and seroreverters in the first 18 months of life; IgA, IgG, and IgM as surrogate markers of infection; and IgA, IgG, and IgM levels in the first 5 years in infected children, according to clinical outcome. The Mann-Whitney test was used for comparison between groups. Surrogate markers were assessed according to sensitivity, specificity, positive and negative predictive values, and J index. RESULTS: Infected children, when compared to seroreverters, showed significantly higher levels of: IgM from the 1st to the 5th trimester; IgA and IgG from the 2nd to the 6th trimester (P </= 0.05). Levels of IgA >/= 90 mg/dl in the 2nd trimester and IgG >/= 1,700 mg/ dl or 1,200 mg/dl in the 2nd and 3rd trimesters were associated with HIV infection with J indexes of 0.97, 0.92, and 0.93, respectively. Infected children in the B and C categories, compared to those in the N and A, showed higher levels of IgM from the 2nd to the 4th year, and IgA from the 3rd to the 5th year (P </= 0.05). CONCLUSIONS: The temporal progression of IgA, IgG, and IgM levels showed an early and intense stimulation to the synthesis of immunoglobulin in infected children. Clinical and epidemiological indicators showed that such levels may be surrogate markers of infection. Higher IgM and IgA levels from the 2nd to the 5th year in more severely infected children suggest a dysfunction in immune regulation secondary to persistent antigenic stimulation.

Journal Article↗
PubMedDate not supplied

[Evolution of hematological parameters in a group of children with human immunodeficiency virus infection - HIV 1]

OBJECTIVE: To analyze the evolution of clinical and hematological aspects of the children infected with HIV 1. METHODS: Using the CDC criteria, 1994, 37 children with HIV infection were selected, followed up at the Immunodeficiency Clinic at UNICAMP. The study is longitudinal descriptive. Complete blood count, ferritin, serum iron, TIBC and direct Coombs were carried out. RESULTS: The clinical category that predominated wasB(45.94%) and categories A and C were equal (27.03%). All of them were having antiretroviral therapy. Hypochromic and microcytic anemia were seen in 100% of patients up to 12 months of age. There was association between anemia and the progression of the disease, both clinical (p=0.031) and immunological (p=0.0027) and with lymphopenia too (p=0.033). Thrombocytopenia occurred in 10 to 25% of the patients. Low serical ferritin was seen in 2.7% of the cases and low serum iron in 11.1%. All the 15 patients analyzed had negative Coombs test. There was weight and height reduction in 23.5 to 45% of the children and 70.3% had clinical manifestations up to 9 months of age. During the follow up 13.2% of the patients died. CONCLUSIONS: There was association between anemia and lymphopenia with the progression of the disease. In relation to the aetiology of the anemia, about 10% can be considered anemia of chronic disease. Probably the hematological abnormalities seen in peripheral blood are the consequences of loss of control of cellular death mechanism and hematopoiesis in individuals infected by HIV 1.

Journal Article↗
PubMedDate not supplied

[Clinical aspects and complete blood counts in children exposed to HIV-1: comparison between infected patients and seroreverters]

OBJECTIVE: To analyze the evolution of clinical and hematological aspects of children exposed to the vertical transmission of HIV-1, comparing infected patients with uninfected ones or seroreverters. METHODS: Prospective, descriptive, longitudinal study. We analyzed 79 children born from HIV-1 infected mothers, under clinical follow up from March, 1996 until November, 1997, at the Immunodeficiency division of the Hospital de Clínicas da Unicamp (State University Hospital of Campinas). RESULTS: Failure to thrive was observed in both groups, but was greater among seroreverters. Among the infected children, 23 mothers did not use AZT during pregnancy, 16 of them (61.5%) had been breastfed, four were classified into clinical category N, seven into A and fifteen into B. Clinical manifestations in patients younger than one year were seen in 18 infected children (69.2%). Anemia was observed in 73.1% of the infected group and in 41.5% of the seroreverters (P<0.008). The comparison between the groups showed that the most common hematologic alterations in the infected children was microcytosis and hypochromia (P<0.05), lymphopenia between 15 and 18 months (P<0.05), monocytosis between 9 and 12 months (P<0.05) and a tendency towards high ferritin levels, with no statistical significance. CONCLUSIONS: Microcytic and hypochromic anemia were observed in both groups: iron deficiency in the uninfected children, and chronic disease anemia in the infected ones. The infected children presented with monocytosis and lymphopenia at an earlier stage.

Journal Article↗
PubMedDate not supplied

Genetic and environmental influences on atopic immune response in early life.

The purpose of our study was to carry out a prospective follow-up of 114 newborns at term (including three pairs of twins), regarding clinical manifestations for atopy during the first year of life. Their IgE levels in cord blood samples, at 3, 6, 9 and 12 months of age were measured and the influence of race, sex, breast-feeding, maternal smoking, family income, month of birth, family history and personal manifestations of atopic disease were evaluated. Total serum immunoglobulin E was quantified by microparticle enzyme immuno-assay (MEIA). The study group consisted of 60 (53%) male neonates, 67 (59%) Caucasians and 47 (41%) blacks. In the clinical follow-up, 32 (28.1%) infants developed obvious atopic disease: 29 infants presented recurrent wheezing, two had cow's milk allergy and one had atopic dermatitis. Probable atopic disease developed in 12 (10.5%) infants, whereas 70 (61.4%) infants showed no manifestations. Cord blood IgE levels in infants with obvious atopic disease was higher when compared to those without (p = 0.024), with 70.97% sensitivity and 46.2% specificity. IgE levels were also significantly different up to 12 months in these groups (p = 0.0001), when the sensitivity was 82.1% and the specificity 54.1%. At this age, the IgE levels were higher in infants with obvious atopy than nonatopic disease in relation to male sex (p = 0.015), black race (p = 0.009), breast-feeding for less than 6 months (p = 0.011) and when the family income was less than three times the minimum wage (about US $300) (p = 0.006). There was no association between IgE levels and family history of atopy. We concluded that immune response for atopy was in a large degree influenced by environmental factors and serum IgE at 12 months was a good marker for identifying infants with risk of atopic disease in early life.

Breast Feeding↗
PubMedDate not supplied

Mast cell quantification in the skin of children with atopic dermatitis: its value in diagnosis and in assessing the effectiveness of therapy.

This study reports on the usefulness of skin mast cell quantification (mast cells(mm2) as a parameter for the diagnosis of atopic dermatitis (AD) and for determining the efficacy of the therapeutic measures employed. Fifteen children with AD of moderate to extreme severity, and which started within the first two years of life, were studied. The therapeutic measures were limited to advice regarding the choice of adequate living conditions and of an appropriate diet in conjunction with the oral administration of hydroxyzine. Before treatment, 11 children with active AD were submitted to biopsies of both affected and non-affected skin. After treatment, in six children who were asymptomatic for at least one month, another biopsy was performed at a site of previous skin disease. A biopsy of a previously affected site was also performed in the other four children with a personal history of AD and who had no symptoms for more than one year. Treatment with hydroxyzine significantly reduced the number of papillar and reticular mast cells/mm3 of affected skin. In children who had been asymptomatic for one month, the number of papillar dermis mast cells/mm3 was greater than in those who had been asymptomatic for 12 months. In both groups of asymptomatic children, the number of mast cells/mm3 of affected skin was greater than in non-affected skin.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗