Evaluation of genotoxic effects of benzene and its derivatives in workers of gas stations.

The search for reliable biomarkers of human exposure to benzene and its derivatives is still subject of research. Many of the proposed biomarkers have limitations ranging from the low sensitivity to the wide variability of results. Thus, the aim of our study was to assess the frequencies of chromosomal abnormalities (CA) and sister chromatid exchanges (SCE) in workers of gas stations, with (cases, n = 19) and without (local controls, n = 6) risk of exposure to benzene and its derivatives, comparing them with the results from the general population (external controls, n = 38). The blood dosages of benzene, toluene, and xylenes were measured in all participants. Blood solvent levels were compared with the findings obtained in cytogenetic evaluation and a research protocol which included data of the workplace, lifestyle, and health of the individuals. We did not detect the presence of benzene and its derivatives and did not find chromosomal damage that may be associated with the gas station activity in cases. Moreover, although we found an association of increased SCE and the working time in the local controls, the values found for SCE are within normal limits. Thus, our evaluation of SCE and CA reflected the levels of benzene and its derivatives observed in the blood. We believe, therefore, that SCE and CA may actually constitute possible tests for the evaluation of these exposures. However, we believe that further studies, including individuals at risk, are important to confirm this assertion.

Gestational and family risk factors for carriers of congenital heart defects in southern Brazil.

BACKGROUND: Congenital heart disease (CHD) is a serious threat to public health. Despite this, its etiology is poorly understood and few cardiac teratogens have been defined. The aim of the present study was to identify gestational and family risk factors for CHD in a sample of patients from a pediatric hospital in southern Brazil. METHODS: A prospective and consecutive sample from subjects with or without CHD, hospitalized at a pediatric intensive care unit, was enrolled. All patients with CHD underwent a GTG-banding karyotype. Chromosomal abnormalities were observed in 47 subjects (15.8%), and these were excluded from the study. The final sample consisted of 250 CHD subjects and 303 controls. RESULTS: After statistical analysis, using logistic regression, the variables age, rural location, gestational loss, use of anti-hypertensive medication, antibiotics and alcohol in the first trimester of pregnancy were all independently associated with CHD. These results were similar to those of some studies and different from others. It should be noted, however, that, for several variables, the data in the literature as well as the present study were insufficient to determine risk. CONCLUSIONS: Some differences found may be explained by genetic factors and sociocultural diversity. In contrast, because CHD consists of a heterogeneous group of lesions, the etiology may vary. The standardization of research data and classification of methods for future studies are essential.

[22q11.2 deletion syndrome and complex congenital heart defects]. / Síndrome de deleção 22q11 e cardiopatias congênitas complexas.

OBJECTIVE: Investigate the frequency of 22q11 deletion syndrome among patients with complex congenital heart disease. METHODS: A prospective and consecutive cohort of patients with complex heart defects was evaluated in their first hospitalization at a cardiac intensive care unit of a pediatric hospital. For each patient a protocol of demographic and clinical evaluation was filled. High resolution karyotype and 22q11 microdeletion by fluorescence in situ hybridization was investigated. The heart defects were classified by a cardiologist of the study. RESULTS: The cohort comprised 66 patients. Karyotypic anomalies were observed in 5 patients (7.6%), however none of those was the 22q11 deletion. Evaluation by means of FISH was successful in 65 patients and 22q11 microdeletion was identified in 2 (3.1%). Of the 66 patients with complex defects, 52 were carriers of conotruncal malformations and in 51 the 22q11 microdeletion analysis by FISH was successful. Both 22q11 microdeletion carriers belonged to this group, representing a frequency of 3.9%. They presented tetralogy of Fallot. CONCLUSION: 22q11DS is a frequent abnormality among patients with complex and conotruncal heart defects. Variations of the 22q11DS frequency among studies seem to be mainly associated to criteria for patient selection and specific characteristics of the population in analysis.

[Oculo-auriculo-vertebral spectrum and cardiac malformations]. / Espectro óculo-aurículo-vertebral e malformações cardíacas.

OBJECTIVE: To verify the frequency and types of congenital heart defects in a sample of patients with oculo-auriculo-vertebral spectrum (OAVS), in an effort to correlate presence of these defects with other clinical characteristics and evolution. METHODS: The sample comprised 33 subjects, all attended in the same center, between January 1975 and December 2007. Twenty two of them were male and eleven female and their ages ranged from 1 day to 17 years. All presented normal karyotype by GTG-Banding. A data collection related to their clinical history, physical examination and result of complementary evaluations was performed. RESULTS: Cardiac abnormalities were observed in 13 patients (39.4%). Of these defects, 5 (38.5%) were conotruncal, tetralogy of Fallot being the main malformation (n=2). Unusual anomalies identified included cor triatriatum and double inlet left ventricle. Significant differences among the clinical characteristics of the group with and without heart defect were only verified in relation to age at first evaluation that was lower in subjects with cardiac malformations. Five patients died, four of them, bearers of congenital heart defects. CONCLUSION: Cardiac malformations, mainly conotruncal and septal defects, are frequent among patients with OAVS. Frequency found in our study was statistically similar to the majority of works described in literature where it ranged from 18 to 58%. Congenital heart defects also represent the main cause of death of these subjects. Thus, a cardiac evaluation should always be performed in these patients, especially at an early age.

[22q11.2 deletion syndrome: importance of clinical evaluation and FISH analysis]. / Síndrome de deleção 22q11.2: importância da avaliação clínica e técnica de FISH.

OBJECTIVE: The 22q11.2 deletion syndrome nowadays is considered one of the most often observed genetic diseases in humans. It is clinically characterized by a rather wide phenotypic spectrum, with more than 180 clinical features physical as well as behavioral, already described. However, none is pathognomonic or obligatory which makes diagnosis even more difficult. Thus, this study intended to determine the prevalence and clinical characteristics of patients with 22q11.2 microdeletion in a selected sample of subjects with clinical suspicion of 22q11.2 deletion syndrome and normal karyotype. METHODS: A selected sample of 30 patients with clinical suspicion of 22q11.2 deletion syndrome and normal karyotype was evaluated by application of a standard clinical protocol and cytogenetic analysis with fluorescent in situ hybridization. RESULTS: 22q11.2 microdeletion was identified in 3 patients (10%), a prevalence similar to the majority of published studies, which ranged from 4 to 21%. The 22q11.2 deletion syndrome patients in this study were characterized by a variable phenotype and shared few clinical features, in agreement with the literature description. CONCLUSIONS: These findings strengthen the idea that clinical diagnosis of 22q11.2 deletion syndrome is difficult due to the large phenotypic variability. Therefore a detailed clinical evaluation associated to a sensitive test such as fluorescent in situ hybridization analysis is crucial for the identification of these patients.

Clinical and Molecular Characterization of Adult Glioblastomas in Southern Brazil.

We investigated 113 adult Brazilian patients with glioblastoma (GBM) for comparison with patients from distinct geographical areas and evaluation of suitability for novel targeted therapies. Patients were assessed for clinical features and tumor genomic characteristics such as ROS1 and NTRK1 rearrangements, KIT, PDGFRA, and KDR amplification, and RB1 deletion using multicolor fluorescence in situ hybridization. The majority of patients were male (53%), over 40 years (94%), with tumor located in single site (64%), in the right cerebral hemisphere (60%), and underwent partial resection (71%); 14% presented complications after surgery. The main clinical sign at diagnosis was focal abnormality (57%); frontal (31%); and temporal (20%) regions were most commonly affected. Median hospitalization time was 20 days, median survival was 175 days. One tumor was positive for rearrangement in NTRK1 and another in ROS1 (0.9% each). PDGFRA was amplified in 20% of cases, often co-amplified with KDR (>90%) and KIT (>60%). RB1 was deleted in 16% of patients. There was no association between these molecular abnormalities and patient survival. However, older age, complications after surgery, and right-sided tumors were independent variables associated with patient survival. This study contributes information on the molecular profile of glioblastomas in Latin America possibly supporting new target therapies.

Clinical and cytogenetic features of a Brazilian sample of patients with phenotype of oculo-auriculo-vertebral spectrum: a cross-sectional study.

CONTEXT AND OBJECTIVE: Oculo-auriculo-vertebral spectrum (OAVS) is considered to be a defect of embryogenesis involving structures originating from the first branchial arches. Our objective was to describe the clinical and cytogenetic findings from a sample of patients with the phenotype of OAVS. DESIGN AND SETTING: Cross-sectional study in a referral hospital in southern Brazil. METHODS: The sample consisted of 23 patients who presented clinical findings in at least two of these four areas: orocraniofacial, ocular, auricular and vertebral. The patients underwent a clinical protocol and cytogenetic evaluation through high-resolution karyotyping, fluorescence in situ hybridization for 5p and 22q11 microdeletions and investigation of chromosomal instability for Fanconi anemia. RESULTS: Cytogenetic abnormalities were observed in three cases (13%) and consisted of: 47,XX,+mar; mos 47,XX,+mar/46,XX; and 46,XX,t(6;10)(q13; q24). We observed cases of OAVS with histories of gestational exposition to fluoxetine, retinoic acid and crack. One of our patients was a discordant monozygotic twin who had shown asymmetrical growth restriction during pregnancy. Our patients with OAVS were characterized by a broad clinical spectrum and some presented atypical findings such as lower-limb reduction defect and a tumor in the right arm, suggestive of hemangioma/lymphangioma. CONCLUSIONS: We found a wide range of clinical characteristics among the patients with OAVS. Different chromosomal abnormalities and gestational expositions were also observed. Thus, our findings highlight the heterogeneity of the etiology of OAVS and the importance of these factors in the clinical and cytogenetic evaluation of these patients.

Congenital heart disease and chromossomopathies detected by the karyotype.

OBJECTIVE: To review the relationship between congenital heart defects and chromosomal abnormalities detected by the karyotype. DATA SOURCES: Scientific articles were searched in MEDLINE database, using the descriptors "karyotype" OR "chromosomal" OR "chromosome" AND "heart defects, congenital". The research was limited to articles published in English from 1980 on. DATA SYNTHESIS: Congenital heart disease is characterized by an etiologically heterogeneous and not well understood group of lesions. Several researchers have evaluated the presence of chromosomal abnormalities detected by the karyotype in patients with congenital heart disease. However, most of the articles were retrospective studies developed in Europe and only some of the studied patients had a karyotype exam. In this review, only one study was conducted in Latin America, in Brazil. It is known that chromosomal abnormalities are frequent, being present in about one in every ten patients with congenital heart disease. Among the karyotype alterations in these patients, the most important is the trisomy 21 (Down syndrome). These patients often have associated extra-cardiac malformations, with a higher risk of morbidity and mortality, which makes heart surgery even more risky. CONCLUSIONS: Despite all the progress made in recent decades in the field of cytogenetic, the karyotype remains an essential tool in order to evaluate patients with congenital heart disease. The detailed dysmorphological physical examination is of great importance to indicate the need of a karyotype.

Tri-allelic pattern at the TPOX locus: a familial study.

Alleles at the TPOX STR locus have 6-14 different numbers of a four-nucleotide (AATG) repeat motif arranged in tandem. Although tri-allelic genotypes are generally rare, the TPOX tri-allelic pattern has a higher frequency, varying widely among populations. Despite this, there are few accurate reports to disclose the nature of the TPOX third allele. In this work we present data obtained from 45 individuals belonging to the same pedigree, in which there are cases of tri-allelic TPOX genotypes. The subjects were apparently healthy with a normal biological development. We noticed six tri-allelic cases in this family, and all of them were women. Karyotype analysis showed no occurrence of partial 2p trisomy. All the tri-allelic cases had the genotype 8-10-11, probably due to three copies of the TPOX STR sequence in all cells (Type 2 tri-allelic pattern). Based on previous data we assumed the allele 10 as the TPOX third allele. The pedigree analyses show evidences that the TPOX extra-allele was the allele10, it is placed far from the main TPOX locus, and that there is a potential linkage of the TPOX extra-allele-10 with Xq. This was the first study that included a large pedigree analysis in order to understand the nature TPOX tri-allelic pattern.

Gómez-López-Hernández syndrome in a child born to consanguineous parents: new evidence for an autosomal-recessive pattern of inheritance?

BACKGROUND: Gómez-López-Hernández syndrome is a rare genetic disease characterized by scalp alopecia with trigeminal anesthesia, brachycephaly or turribrachycephaly, midface retrusion, and rhombencephalosynapsis. We report the second case with this condition who presented with consanguineous parents. PATIENT: This boy was evaluated shortly after birth because of suspected craniosynostosis. He was the only son of healthy, consanguineous parents (his maternal grandmother and his paternal great-grandfather were siblings). His examination was notable for turribrachycephaly, prominent forehead, bilateral parietotemporal alopecia, midfacial retrusion, anteverted nostrils, micrognathia, low-set and posteriorly rotated ears, and short neck with redundant skin. Radiographs and tridimensional computed tomography scan of skull revealed lambdoid craniosynostosis. Brain magnetic resonance imaging revealed complete rhombencephalosynapsis, aqueductal stenosis, fused colliculi, abnormal superior cerebellar penducle, mild ventriculomegaly, and dysgenesis of the corpus callosum. CONCLUSIONS: Since its first description, 34 patients with this condition have been reported. The etiology of Gómez-López-Hernández syndrome is unknown. However, it is noteworthy that the patient in this report presented with a family history of consanguinity because this finding reinforces the possibility of an autosomal-recessive inheritance for this condition.

45,X/46,XY mosaicism: report on 14 patients from a Brazilian hospital. A retrospective study.

CONTEXT AND OBJECTIVE: 45,X/46,XY mosaicism, or mixed gonadal dysgenesis, is considered to be a rare disorder of sex development. The aim of our study was to investigate the clinical and cytogenetic characteristics of patients with this mosaicism. DESIGN AND SETTING: A retrospective study in a referral hospital in southern Brazil. METHODS: Our sample consisted of patients diagnosed at the clinical genetics service of a referral hospital in southern Brazil, from 1975 to 2012. Clinical and cytogenetic data were collected from the medical records. RESULTS: Fourteen patients were included in the sample, with ages at the first evaluation ranging from 2 days to 38 years. Nine of them had female sex of rearing and five, male. Regarding the external genitalia, most were ambiguous (n = 10). One patient presented male phenotype and was treated for a history of azoospermia, while three patients presented female phenotype, of whom two had findings of Turner syndrome and one presented secondary amenorrhea alone. Some findings of Turner syndrome were observed even among patients with ambiguous genitalia. None presented gonadal malignancy. One patient underwent surgical correction for genital ambiguity and subsequent exchange of sex of rearing. Regarding cytogenetics, we did not observe any direct correlation between percentages of cell lines and phenotype. CONCLUSIONS: 45,X/46,XY mosaicism can present with a wide variety of phenotypes resulting from the involvement of different aspects of the individual. All these observations have important implications for early recognition of these patients and their appropriate management.

Congenital heart defects and extracardiac malformations.

OBJECTIVE: To review the association between congenital heart defects and extracardiac malformations. DATA SOURCES: Scientific articles were searched in the Medline, Lilacs, and SciELO databases, using the descriptors "congenital heart disease," "congenital heart defects," "congenital cardiac malformations," "extracardiac defects," and "extracardiac malformations." All case series that specifically explored the association between congenital heart defects and extracardiac malformations were included. DATA SYNTHESIS: Congenital heart diseases are responsible for about 40% of birth defects, being one of the most common and severe malformations. Extracardiac malformations are observed in 7 to 50% of the patients with congenital heart disease, bringing a greater risk of comorbidity and mortality and increasing the risks related to heart surgery. Different studies have attempted to assess the presence of extracardiac abnormalities in patients with congenital heart disease. Among the changes described, those of the urinary tract are more often reported. However, no study has evaluated all patients in the same way. CONCLUSIONS: Extracardiac abnormalities are frequent among patients with congenital heart disease, and patients with these alterations may present an increased risk of morbimortality. Therefore, some authors have been discussing the importance and cost-effectiveness of screening these children for other malformations by complementary exams.

Trisomy 18: review of the clinical, etiologic, prognostic, and ethical aspects.

OBJECTIVE: To review the clinical, etiological, diagnostic, and prognostic characteristics of trisomy 18 (Edwards syndrome). DATA SOURCES: Scientific articles in the MedLine, Lilacs, and SciELO databases were searched using the descriptors 'trisomy 18' and 'Edwards syndrome'. The research was not limited to a specific time period and included all articles in such databases. DATA SYNTHESIS: Edwards syndrome is a disease characterized by a broad clinical picture and a very reserved prognosis. There are descriptions of more than 130 different anomalies, which can involve virtually all organs and systems. Its findings are the result of the presence of three copies of chromosome 18. The main chromosomal constitution observed among these patients is a free trisomy of chromosome 18, which is associated with the phenomenon of nondisjunction, especially in maternal gametogenesis. Most fetuses with Edwards syndrome die during the embryonic and fetal life. The median of survival among live births has usually varied between 2.5 and 14.5 days. CONCLUSIONS: Knowledge on the clinical picture and on the prognosis of Edwards syndrome patients is of great importance regarding the neonatal care and the decisions about invasive treatments. The speed to have a confirmed diagnosis is important for making decisions about medical procedures. Often, interventions are performed under emergency conditions, without many opportunities for discussion, and they involve difficult medical and ethical issues.

Craniofacial abnormalities among patients with Edwards Syndrome.

UNLABELLED: OBJECTIVE To determine the frequency and types of craniofacial abnormalities observed in patients with trisomy 18 or Edwards syndrome (ES). METHODS This descriptive and retrospective study of a case series included all patients diagnosed with ES in a Clinical Genetics Service of a reference hospital in Southern Brazil from 1975 to 2008. The results of the karyotypic analysis, along with clinical data, were collected from medical records. RESULTS: The sample consisted of 50 patients, of which 66% were female. The median age at first evaluation was 14 days. Regarding the karyotypes, full trisomy of chromosome 18 was the main alteration (90%). Mosaicism was observed in 10%. The main craniofacial abnormalities were: microretrognathia (76%), abnormalities of the ear helix/dysplastic ears (70%), prominent occiput (52%), posteriorly rotated (46%) and low set ears (44%), and short palpebral fissures/blepharophimosis (46%). Other uncommon - but relevant - abnormalities included: microtia (18%), orofacial clefts (12%), preauricular tags (10%), facial palsy (4%), encephalocele (4%), absence of external auditory canal (2%) and asymmetric face (2%). One patient had an initial suspicion of oculo-auriculo-vertebral spectrum (OAVS) or Goldenhar syndrome. CONCLUSIONS: Despite the literature description of a characteristic clinical presentation for ES, craniofacial alterations may be variable among these patients. The OAVS findings in this sample are noteworthy. The association of ES with OAVS has been reported once in the literature.

Chromosomal abnormalities in patients with congenital heart disease.

BACKGROUND: Chromosomal abnormalities (CAs) are an important cause of congenital heart disease (CHD). OBJECTIVE: Determine the frequency, types and clinical characteristics of CAs identified in a sample of prospective and consecutive patients with CHD. METHOD: Our sample consisted of patients with CHD evaluated during their first hospitalization in a cardiac intensive care unit of a pediatric referral hospital in Southern Brazil. All patients underwent clinical and cytogenetic assessment through high-resolution karyotype. CHDs were classified according to Botto et al. Chi-square, Fisher exact test and odds ratio were used in the statistical analysis (p < 0.05). RESULTS: Our sample consisted of 298 patients, 53.4% males, with age ranging from 1 day to 14 years. CAs were observed in 50 patients (16.8%), and 49 of them were syndromic. As for the CAs, 44 (88%) were numeric (40 patients with +21, 2 with +18, 1 with triple X and one with 45,X) and 6 (12%) structural [2 patients with der(14,21), +21, 1 with i(21q), 1 with dup(17p), 1 with del(6p) and 1 with add(18p)]. The group of CHDs more often associated with CAs was atrioventricular septal defect. CONCLUSIONS: CAs detected through karyotyping are frequent in patients with CHD. Thus, professionals, especially those working in Pediatric Cardiology Services, must be aware of the implications that performing the karyotype can bring to the diagnosis, treatment and prognosis and for genetic counseling of patients and families.

Trisomy 18 and neural tube defects.

BACKGROUND: Trisomy 18 or Edwards syndrome is a chromosomal abnormality characterized by a broad clinical picture and a limited survival. More than 130 different abnormalities have been described in these patients-among them are neural tube defects. METHODS: We verified the frequency and types of major neural tube defects observed among patients with trisomy 18. Our sample consisted of consecutive patients evaluated by a clinical genetics service of a referral hospital in southern Brazil between 1975 and 2008. Fisher's exact test (two-tailed) and chi-square test with Yates' correction were used to compare frequencies (P < 0.05 values were considered as significant). RESULTS: During the period of evaluation, we identified 50 patients with trisomy 18; 33 (66%) were female and age at the first evaluation ranged from 1 day to 16 years (median 14 days). One cell line with full trisomy 18 was the predominant cytogenetic finding (90%). Three patients (6%) had major neural tube defects, all females. These were two patients (4%) with encephaloceles and one (2%) with myelomeningocele. This last patient undergo to correction surgery on her first day of life. CONCLUSIONS: Our data, in accordance with the literature, support the idea that the presence of neural tube defects among patients with trisomy 18 is not coincidental (i.e., these defects are actually part of the spectrum of abnormalities presented in trisomy 18). Thus, the diagnosis of trisomy 18 should be considered in children with major neural tube defects, especially in the presence of other abnormalities or dysmorphisms.

Type 1 diabetes in a patient with Ellis-van Creveld syndrome.

CONTEXT: Ellis-van Creveld (EVC) syndrome is a rare autosomal recessive disease characterized by disproportionate short stature, narrow thorax, postaxial polydactyly, nail and tooth abnormalities and congenital heart disease. CASE REPORT: The patient was a 22-year-old Caucasian man, the third child of consanguineous parents. He received the diagnosis of insulin-dependent diabetes mellitus (DM) at 16 years of age, and around one year later, he underwent surgery to correct a partial atrioventricular septal defect. Upon physical examination, at 22 years of age, he presented stature of 145.5 cm (P3), weight of 49 kg (P3), head circumference of 54 cm (P2-50), high palate, absence of one of the lower lateral incisor teeth, narrow shoulders, narrowing of the upper thorax, scoliosis, rhizomelic shortening of the upper limbs, brachydactyly, postaxial polydactyly and clinodactyly of the second and third fingers. The lower limbs showed rhizomelic shortening with significant genu valgum (knock-knee deformity), small feet with postaxial polydactyly, syndactyly between the second and third toes and hallux valgus. Multiple melanocytic nevi were evident on the face, thorax and limbs. At that time, he was using neutral protamine Hagedorn (NPH) insulin, with poorly controlled DM. The clinical findings presented led to the diagnosis of EVC syndrome. Only one case of this syndrome has been described with DM so far. Attention is drawn to the fact that the genes associated with this syndrome are located close to those of the Wolfram syndrome, a condition that leads to early-onset diabetes.