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Objective The objective of this study was to compare demographic data, clinical/laboratorial features and disease activity at diagnosis in three different groups with distinct time intervals between onset of signs/symptoms and disease diagnosis. Methods A multicenter study was performed in 1555 childhood-onset systemic lupus erythematosus (American College of Rheumatology criteria) patients from 27 pediatric rheumatology services. Patients were divided into three childhood-onset systemic lupus erythematosus groups: A: short time interval to diagnosis (<1 month); B: intermediate time interval (≥1 and <3 months); and C: long time interval (≥3 months). An investigator meeting was held to define the protocol. Demographic data, SLICC classification criteria and SLEDAI-2 K were evaluated. Results The number of patients in each group was: A = 60 (4%); B = 522 (33.5%); and C = 973 (62.5%). The median age at diagnosis (11.1 (4.2-17) vs. 12 (1.9-17.7) vs. 12.5 (3-18) years, P = 0.025) was significantly lower in group A compared with groups B and C. The median number of diagnostic criteria according to SLICC (7 (4-12) vs. 6 (4-13) vs. 6 (4-12), P < 0.0001) and SLEDAI-2 K (18 (6-57) vs. 16 (2-63) vs. 13 (1-49), P < 0.0001) were significantly higher in group A than the other two groups. The frequency of oral ulcers in the palate (25% vs. 15% vs. 11%, P = 0.003), pleuritis (25% vs. 24% vs. 14%, P < 0.0001), nephritis (52% vs. 47% vs. 40%, P = 0.009), neuropsychiatric manifestations (22% vs. 13% vs. 10%, P = 0.008), thrombocytopenia (32% vs. 18% vs. 19%, P = 0.037), leucopenia/lymphopenia (65% vs. 46% vs. 40%, P < 0.0001) and anti-dsDNA antibodies (79% vs. 66% vs. 61%, P = 0.01) were significantly higher in group A compared with the other groups. In contrast, group C had a less severe disease characterized by higher frequencies of synovitis (61% vs. 66% vs. 71%, P = 0.032) and lower frequencies of serositis (37% vs. 33% vs. 25%, P = 0.002), proteinuria >500 mg/day (48% vs. 45% vs. 36%, P = 0.002) and low complement levels (81% vs. 81% vs. 71%, P < 0.0001) compared with groups A or B. Conclusions Our large Brazilian multicenter study demonstrated that for most childhood-onset systemic lupus erythematosus patients, diagnosis is delayed probably due to mild disease onset. Conversely, the minority has a very short time interval to diagnosis and a presentation with a more severe and active multisystemic condition.
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Diagnóstico Tardío , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/epidemiología , Adolescente , Edad de Inicio , Biomarcadores/sangre , Brasil/epidemiología , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Lupus Eritematoso Sistémico/sangre , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
Objective The objective of this study was to assess outcomes of childhood systemic lupus erythematosus (cSLE) in three different age groups evaluated at last visit: group A early-onset disease (<6 years), group B school age (≥6 and <12 years) and group C adolescent (≥12 and <18 years). Methods An observational cohort study was performed in ten pediatric rheumatology centers, including 847 cSLE patients. Results Group A had 39 (4%), B 395 (47%) and C 413 (49%). Median disease duration was significantly higher in group A compared to groups B and C (8.3 (0.1-23.4) vs 6.2 (0-17) vs 3.3 (0-14.6) years, p < 0.0001). The median Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR-DI) (0 (0-9) vs 0 (0-6) vs 0 (0-7), p = 0.065) was comparable in the three groups. Further analysis of organ/system damage revealed that frequencies of neuropsychiatric (21% vs 10% vs 7%, p = 0.007), skin (10% vs 1% vs 3%, p = 0.002) and peripheral vascular involvements (5% vs 3% vs 0.3%, p = 0.008) were more often observed in group A compared to groups B and C. Frequencies of severe cumulative lupus manifestations such as nephritis, thrombocytopenia, and autoimmune hemolytic anemia were similar in all groups ( p > 0.05). Mortality rate was significantly higher in group A compared to groups B and C (15% vs 10% vs 6%, p = 0.028). Out of 69 deaths, 33/69 (48%) occurred within the first two years after diagnosis. Infections accounted for 54/69 (78%) of the deaths and 38/54 (70%) had concomitant disease activity. Conclusions This large multicenter study provided evidence that early-onset cSLE group had distinct outcomes. This group was characterized by higher mortality rate and neuropsychiatric/vascular/skin organ damage in spite of comparable frequencies of severe cumulative lupus manifestations. We also identified that overall death in cSLE patients was an early event mainly attributed to infection associated with disease activity.
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Anemia Hemolítica Autoinmune/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Nefritis/complicaciones , Trombocitopenia/complicaciones , Adolescente , Edad de Inicio , Anemia Hemolítica Autoinmune/diagnóstico , Anemia Hemolítica Autoinmune/patología , Brasil/epidemiología , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Inmunosupresores/uso terapéutico , Lactante , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/epidemiología , Lupus Eritematoso Sistémico/mortalidad , Mortalidad , Nefritis/diagnóstico , Nefritis/epidemiología , Nefritis/mortalidad , Embarazo , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Trombocitopenia/diagnóstico , Trombocitopenia/patología , Resultado del TratamientoRESUMEN
OBJECTIVE: To describe onset features, classification and treatment of juvenile dermatomyositis (JDM) and juvenile polymyositis (JPM) from a multicentre registry. METHODS: Inclusion criteria were onset age lower than 18 years and a diagnosis of any idiopathic inflammatory myopathy (IIM) by attending physician. Bohan & Peter (1975) criteria categorisation was established by a scoring algorithm to define JDM and JPM based on clinical protocol data. RESULTS: Of the 189 cases included, 178 were classified as JDM, 9 as JPM (19.8: 1) and 2 did not fit the criteria; 6.9% had features of chronic arthritis and connective tissue disease overlap. Diagnosis classification agreement occurred in 66.1%. Median onset age was 7 years, median follow-up duration was 3.6 years. Malignancy was described in 2 (1.1%) cases. Muscle weakness occurred in 95.8%; heliotrope rash 83.5%; Gottron plaques 83.1%; 92% had at least one abnormal muscle enzyme result. Muscle biopsy performed in 74.6% was abnormal in 91.5% and electromyogram performed in 39.2% resulted abnormal in 93.2%. Logistic regression analysis was done in 66 cases with all parameters assessed and only aldolase resulted significant, as independent variable for definite JDM (OR=5.4, 95%CI 1.2-24.4, p=0.03). Regarding treatment, 97.9% received steroids; 72% had in addition at least one: methotrexate (75.7%), hydroxychloroquine (64.7%), cyclosporine A (20.6%), IV immunoglobulin (20.6%), azathioprine (10.3%) or cyclophosphamide (9.6%). In this series 24.3% developed calcinosis and mortality rate was 4.2%. CONCLUSION: Evaluation of predefined criteria set for a valid diagnosis indicated aldolase as the most important parameter associated with definite JDM category. In practice, prednisone-methotrexate combination was the most indicated treatment.
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Dermatomiositis/clasificación , Dermatomiositis/diagnóstico , Adolescente , Edad de Inicio , Brasil , Niño , Preescolar , Dermatomiositis/tratamiento farmacológico , Progresión de la Enfermedad , Femenino , Glucocorticoides/uso terapéutico , Humanos , Lactante , Masculino , Selección de Paciente , Sistema de Registros , Análisis de Regresión , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
We evaluated the prevalence and clinical associations of amenorrhea in 298 female juvenile systemic lupus erythematosus (JSLE) patients (ACR criteria) followed in 12 Brazilian Paediatric Rheumatology centres. Amenorrhea was observed in 35 patients (11.7%) with a mean duration of 7.2 +/- 3.6 months. The hormones were performed in 32/35 patients and none of them had FSH and LH levels above and estradiol below the normal range according to pubertal changes. JSLE patients with amenorrhea were younger (15.04 +/- 2.5 versus 17.8 +/- 3.1 years; P = 0.001), and had a shorter period of time between menarche and current age (3.4 +/- 2.9 versus 6.7 +/- 5.4 years; P = 0.001). Interestingly, the frequency, cumulative dose, number of pulses and duration of intravenous cyclophosphamide treatment were alike in patients with and without amenorrhea (P > 0.05). In contrast, patients with amenorrhea had significantly higher SLEDAI (P = 0.01) and SLICC/ACR-DI (P = 0.024) scores compared to those without this condition. Independent risk factors identified by multivariate analysis were higher SLEDAI (OR = 1.059; CI = 1.004-1.116; P = 0.034) and SLICC/ACR-DI (OR = 2.125; IC = 1.373-3.291; P = 0.001) scores. Our data suggest that in spite of immunosuppressive therapy, JSLE patients have an adequate ovarian follicular reserve and amenorrhea is particularly associated with disease activity and damage.
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Amenorrea/etiología , Lupus Eritematoso Sistémico/complicaciones , Adolescente , Adulto , Edad de Inicio , Amenorrea/sangre , Amenorrea/epidemiología , Biomarcadores/sangre , Brasil/epidemiología , Niño , Estradiol/sangre , Femenino , Fluoroinmunoensayo , Hormona Folículo Estimulante/sangre , Estudios de Seguimiento , Humanos , Incidencia , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/epidemiología , Hormona Luteinizante/sangre , Ciclo Menstrual/sangre , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
In this study we have optimised the enzyme immunoassay (ELISA) to quantify CD59 antigen in human serum or plasma. The glycosyl-phosphatidylinositol (GPI)-linked form of CD59 is known to complex with serum high-density lipoprotein. For ELISA optimisation, therefore, we investigated the effect of detergents, added to the sample diluent, on the determined values of CD59. Values obtained in the presence of octyl-glucoside (OG) for 20 adults aged 18-35 years and 17 children 1-5 years old were, respectively, 33-119 ng/ml (mean +/- S.D.: 66+/-22 ng/ml) and 37-143 ng/ml (76+/-33 ng/ml). These results were higher than those measured without OG and were in contrast with published results showing absence, or eight to nine times lower levels, of the protein in serum. A known range for serum concentrations of CD59 in healthy individuals will establish an important reference point for clinical work and for the investigation of diseases involving the complement membrane attack complex (MAC) and its regulation.
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Antígenos CD59/sangre , Antígenos CD59/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Glucósidos/química , Glicosilfosfatidilinositoles/metabolismo , Adolescente , Adulto , Antígenos CD59/química , Antígenos CD59/inmunología , Preescolar , Glicosilfosfatidilinositoles/química , Humanos , Lactante , Octoxinol , Polietilenglicoles/químicaRESUMEN
Previous studies of human in vivo complement protein levels have only compared data for neonates with that from adult sera. Here, we establish the normal concentration ranges of the following complement regulatory proteins in healthy Brazilian children of different age groups (neonates: 1 month-1 year, 1-6 years and 6-13 years) and in adults: factor H (fH), factor I (fI), C4b-binding protein (C4 BP), properdin and vitronectin. We found that the concentrations of fH, fI, properdin and vitronectin in neonates are significantly lower than in adults. Remarkably, the concentration of C4 BP is below the method resolution (<50 micro g/ml) in 76% of the sera from neonates, while adults presented 199-532 microg/ml of C4 BP in their sera. The concentration of properdin in the sera from neonates and up to 1-year-old children was less than that observed in older children. Adults presented vitronectin levels significantly higher than all the other age groups in the study. No significant sex differences in the concentrations of all the studied regulatory proteins were detected. This study reveals the ontogeny of complement system in greater detail than previously available and may point to the reasons why neonates have higher susceptibility to develop life-threatening pyogenic infections. These reference values will be of use in clinical and laboratory investigations of disorders associated with low levels of these regulatory proteins.
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Factor H de Complemento/análisis , Proteínas Inactivadoras de Complemento , Fibrinógeno/análisis , Glicoproteínas/análisis , Properdina/análisis , Vitronectina/análisis , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Humanos , Lactante , Valores de ReferenciaRESUMEN
BACKGROUND: Sensitization to indoor allergens, particularly to dust mites, is a strong risk factor for asthma in children and adults. Assessment of sensitization is carried out using in vivo and in vitro tests to detect specific IgE antibodies. OBJECTIVE: To investigate IgE antibody responses to mites in patients with asthma, wheezing and/or rhinitis, using chimeric ELISA to measure specific IgE antibodies to mite allergens Der p 1 and Der p 2. METHODS: Specific IgE antibodies to Der p 1 and Der p 2 were quantified by chimeric ELISA, and compared with IgE to Dermatophagoides pteronyssinus (Dpt) measured using the CAP system (Pharmacia). A panel of sera from 212 patients with asthma, wheezing and/or rhinitis and 11 controls was analysed. RESULTS: There was a significant correlation between IgE to Dpt measured by CAP and IgE to Der p 1 (r = 0.81, P < 0.001), Der p 2 (r = 0.79, P < 0.001) and combined Der p 1 and Der p 2 (r = 0.86, P < 0.001). Seventy per cent of all patients had IgE to Dpt, and of those, 76.5% had IgE to Der p 1, 79.2% had IgE to Der p 2 and 83.1% had IgE to Der p 1 and Der p 2 combined. Considering the cut-off level of 2 IU/mL of IgE to either Der p 1 or Der p 2, the predictive value for a positive IgE to Dpt by CAP was greater than 95%. CONCLUSIONS: The chimeric ELISA allowed accurate quantification of IgE antibodies to Dpt allergens Der p 1 and Der p 2, and it could be useful for studying immune responses to mites in patients with asthma and/or rhinitis.
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Anticuerpos/sangre , Antígenos Dermatofagoides/inmunología , Asma/inmunología , Inmunoglobulina E/sangre , Rinitis Alérgica Perenne/inmunología , Adolescente , Adulto , Animales , Proteínas de Artrópodos , Estudios de Casos y Controles , Niño , Preescolar , Cisteína Endopeptidasas , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Lactante , Curva ROC , Estadísticas no ParamétricasRESUMEN
We report the cross-cultural adaptation and validation into Brazilian-Portuguese of the parent's version of two health related quality of life instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific health instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health instrument designed to capture the physical and psychosocial well-being of children regardless the underlying disease. The Brazilian CHAQ was revalidated, while the CHQ has been derived from the Portuguese version. A total of 471 subjects were enrolled: 157 patients with JIA (27% systemic onset, 38% polyarticular onset, 9% extended oligoarticular subtype, and 26% persistent oligoarticular subtype) and 314 healthy children. The CHAQ discriminated clinically healthy subjects from JIA patients, with the systemic, polyarticular and extended oligoarticular subtypes having a higher degree of disability, pain, and lower overall well-being scores when compared to their healthy peers. Also the CHQ discriminated clinically healthy subjects from JIA patients, with the systemic onset, polyarticular onset and extended oligoarticular subtypes having a lower physical and psychosocial well-being score when compared to their healthy peers. In conclusion the Brazilian versions of the CHAQ-CHQ are reliable and valid tools for the combined physical and psychosocial assessment of children with JIA.
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Artritis Juvenil/diagnóstico , Comparación Transcultural , Estado de Salud , Encuestas y Cuestionarios , Brasil , Niño , Características Culturales , Evaluación de la Discapacidad , Femenino , Humanos , Lenguaje , Masculino , Psicometría , Calidad de Vida , Reproducibilidad de los ResultadosRESUMEN
Asthma and allergy are the most common diseases associated with cockroach infestation of houses in the United States and other parts of the world. Sensitization and exposure to cockroach allergens is associated with increased asthma morbidity in the United States, especially among lower socioeconomic groups, including African American and Hispanic populations. Exposure to cockroach allergens in the first 3 months of life has been associated with repeated wheezing and asthma. The principal domestic cockroach species are Blattella germanica and Periplaneta americana. Both species produce several potent allergens, including Bla g 2 (inactive aspartic proteinase), Bla g 4 (calycin), Bla g 5 (glutathione-S-transferase), the group 1 cross-reactive allergens Bla g 1 and Per a 1, and tropomyosin. Structural homology between tropomyosins from cockroaches, mites, and shrimp may explain clinical cases of the oral allergy syndrome. The 3-dimensional structures of several cockroach allergens are known, and biologically active recombinant allergens have been produced in high-level expression vectors. The use of recombinant cockroach allergens should allow mechanisms of cockroach-induced asthma to be investigated and may lead to the development of new approaches to asthma treatment. Environmental allergen measurements of Bla g 1 and Bla g 2 have allowed exposure levels that cause allergic sensitization to be established. Abatement studies have shown that a sustained decrease in cockroach allergen levels is difficult but can be accomplished by professional application of insecticides, together with rigorous household cleaning. Cockroach asthma is an important public health problem that affects patients who are the least likely to be compliant with treatment with asthma medications or environmental control. Patient education, improvements in the housing stock, and improvements in environmental and immunologic treatment strategies are likely to be the most successful approaches to reduce the prevalence of cockroach-induced asthma.
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Asma/inmunología , Cucarachas/inmunología , Alérgenos , AnimalesRESUMEN
Cockroach allergy has been recognized as an important cause of asthma. Exposure to high levels of cockroach allergens in the home is a major risk factor for symptoms in sensitized individuals. Previously identified allergens from Blatella germanica and Periplaneta americana include Bla g 2 (inactive aspartic proteinase), Bla g 4 (calycin), Bla g 5 (glutathione-S-transferase), Bla g 6 (troponin), the Group 1 cross-reactive allergens Bla g 1 and Per a 1, Per a 3 (arylphorin), and Per a 7 (tropomyosin). The primary site of cockroach allergen accumulation is the kitchen. However, lower levels of allergen can be found in bedding, on the bedroom floor, and in sofa dust. Strategies for decreasing exposure to cockroach have been investigated. The results suggest that a sustained decrease in cockroach allergen levels is difficult to accomplish, even after successful extermination of cockroach populations. The use of recombinant cockroach allergens may lead to the development of new approaches to asthma treatment in the future.
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Alérgenos/efectos adversos , Cucarachas/inmunología , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire Interior/efectos adversos , Animales , Asma/complicaciones , Asma/etiología , Asma/terapia , Exposición a Riesgos Ambientales/efectos adversos , Enfermedades Ambientales/complicaciones , Enfermedades Ambientales/etiología , Enfermedades Ambientales/terapia , HumanosRESUMEN
OBJECTIVE: The aim of this study was to describe the clinical manifestations and to assess the occurrence of atypical arthritis in ARF patients attending a Pediatric Rheumatology Clinic at the University Hospital of Ribeirão Preto. METHODS: We have studied retrospectively the records of 120 attacks of ARF in 109 children, 3-13 years old, who attended our clinic from January 1990 to December 1995. All children fulfilled the Jones criteria. RESULTS: 77% of the attacks involved arthritis, 62% carditis, 32% chorea, 2.5% subcutaneous nodules and 1.3% erythema marginatum. The number of involved joints was 1 in 3 episodes of ARF, 2-5 in 52, 6-10 in 30 and more than 10 in 5. Arthritis was considered atypical in 43 (47%) of the 92 ARF episodes with arthritis, based on the following criteria: involvement of unusual joints (cervical spine in 24 children, hip in 15, small joints of the hand in 12 or feet in 13); monarthritis (3); duration longer than 3 weeks (26); incomplete response to salicylates (18). Association of these atypical features were frequently present. For instance, considering the 24 episodes with cervical spine involvement, the duration of arthritis was longer than 3 weeks in 13 cases, 10 had insufficient response to salicylates and the hip joint was also involved in 7. Time to reach diagnosis was longer than 4 weeks in 59% of the patients presenting with atypical arthritis compared to 35% in the other patients (p=0.04). Different diagnosis were considered at the beginning of the disease in 40% of the 120 episodes and in 65% of the ones presenting with atypical arthritis (p=0.03). CONCLUSION: We conclude that atypical arthritis was present in a significant proportion of ARF episodes, adding an extra dilemma to the diagnosis of this intriguing disease.
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Values of complement lytic activity of classical and alternative pathways, assessed by measuring the time required to lyse 50% of target red blood cells, and the concentration of complement components C3, C4 and factor B were estimated in the sera of 103 healthy children aged 3 to 14 y. Age-dependent variations were seen in the C3 and factor B concentrations, but not in C4, with the highest values found among 5-6-y-old children. Variations in classical and alternative lytic activity were not detected in this group of children, although the values are significantly different from our previously published data on adults, using the same kinetic assay (1). We also evaluated the relationship between the lytic activity of the classical (CPT) and alternative pathways (APT) and the levels of complement components. There were significant correlations between: APT and factor B, APT and C3, C3 and C4, C3 and factor B, and C4 and factor B concentrations. The normal ranges measured here can be used in the initial screening of Brazilian children presenting diseases involving the complement system. This study also contributes to a better understanding of the complement system ontogeny.
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Complemento C3c/análisis , Complemento C4/análisis , Factor B del Complemento/análisis , Adolescente , Adulto , Factores de Edad , Análisis de Varianza , Brasil , Niño , Preescolar , Ensayo de Actividad Hemolítica de Complemento , Femenino , Humanos , Masculino , Valores de Referencia , Sensibilidad y Especificidad , Estadísticas no ParamétricasRESUMEN
BACKGROUND: Cockroaches produce several proteins that induce IgE antibody responses. Although cockroaches are abundant in warm and humid areas, sensitization to cockroach allergens has not been investigated in Brazil. OBJECTIVE: The aims of this study were to investigate the frequency of cockroach allergy among patients with asthma, rhinitis, or both in Brazil and to identify American cockroach allergens. METHODS: Skin tests using cockroach extracts were performed on children and young adults with asthma, rhinitis, or both. A Periplaneta americana complementary (c)DNA library was screened by using IgE antibodies from Brazilian patients allergic to cockroaches. Reactivity of an mAb directed to Dermatophagoides pteronyssinus tropomyosin against cockroach tissue was examined by immunofluorescence. RESULTS: Cockroach allergy was present in 55% and 79% of the patients, as determined by using skin prick tests alone or combined prick and intradermal tests, respectively. Five cDNA clones reacted with IgE antibody and contained the same sequence. A representative clone (1300 bp), pa 12, coded for a protein that reacted with 50% of the sera from patients allergic to cockroaches on plaque immunoassay and showed a high degree of homology to tropomyosins, particularly those from invertebrates. P americana tropomyosin showed 80%, 81%, and 82% sequence identity to tropomyosins from D pteronyssinus, D farinae, and shrimp, respectively, which have been previously defined as important allergens. An mAb directed against D pteronyssinus tropomyosin, which also recognizes shrimp tropomyosin, showed binding to cockroach striated muscle. CONCLUSION: Our results support the recommendation that cockroach extracts should be routinely used for the evaluation of patients with asthma, rhinitis, or both in Brazil. The identification of P americana tropomyosin as an important allergen will make it possible to investigate cross-reactivity among cockroaches, mites, and food derived from invertebrates.
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Alérgenos/inmunología , Asma/inmunología , Tropomiosina/inmunología , Adolescente , Alérgenos/química , Secuencia de Aminoácidos , Animales , Formación de Anticuerpos/fisiología , Especificidad de Anticuerpos , Antígenos de Plantas , Asma/sangre , Asma/epidemiología , Secuencia de Bases , Brasil/epidemiología , Niño , Preescolar , Clonación Molecular , Cucarachas , Reacciones Cruzadas/inmunología , ADN Complementario/genética , Decápodos/inmunología , Humanos , Inmunización , Immunoblotting , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Ácaros/inmunología , Datos de Secuencia Molecular , Prueba de Radioalergoadsorción , Rinitis/sangre , Rinitis/inmunología , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido NucleicoRESUMEN
The haemolytic activity of complement was evaluated in the serum of healthy children from birth to 2 years of age using the kinetic method for the determination of the time needed to lyse 50% of target red cells (t 1/2). No sex-linked differences were observed in any of the age groups studied and the lowest lytic activity levels for both complement pathways were detected in neonates. The two pathways, however, showed different maturation patterns, i.e., lytic activity levels similar to those of adults were reached between the 1st and 3rd month of life (classical pathway) and around the 13th month (alternative pathway). In the age group of 7 to 24 months, the lytic activity of the classical pathway was higher than in adults. The present data permitted us to establish normal ranges of t 1/2 values for the classical and alternative pathways in serum of healthy neonates and children aged 1 to 24 months.