Investigation of selected genomic deletions and duplications in a cohort of 338 patients presenting with syndromic obesity by multiplex ligation-dependent probe amplification using synthetic probes

Background: Certain rare syndromes with developmental delay or intellectual disability caused by genomic copy number variants (CNVs), either deletions or duplications, are associated with higher rates of obesity. Current strategies to diagnose these syndromes typically rely on phenotype-driven investigation. However, the strong phenotypic overlap between syndromic forms of obesity poses challenges to accurate diagnosis, and many different individual cytogenetic and molecular approaches may be required. Multiplex ligation-dependent probe amplification (MLPA) enables the simultaneous analysis of multiple targeted loci in a single test, and serves as an important screening tool for large cohorts of patients in whom deletions and duplications involving specific loci are suspected. Our aim was to design a synthetic probe set for MLPA analysis to investigate in a cohort of 338 patients with syndromic obesity deletions and duplications in genomic regions that can cause this phenotype.Results: We identified 18 patients harboring copy number imbalances; 18 deletions and 5 duplications. the alterations in ten patients were delineated by chromosomal microarrays, and in the remaining cases by additional MLPA probes incorporated into commercial kits. Nine patients showed deletions in regions of known microdeletion syndromes with obesity as a clinical feature: in 2q37 (4 cases), 9q34 (1 case) and 17p11.2 (4 cases). Four patients harbored CNVs in the DiGeorge syndrome locus at 22q11.2. Two other patients had deletions within the 22q11.2 'distal' locus associated with a variable clinical phenotype and obesity in some individuals. the other three patients had a recurrent CNV of one of three susceptibility loci: at 1q21.1 'distal', 16p11.2 'distal', and 16p11.2 'proximal'.Conclusions: Our study demonstrates the utility of an MLPA-based first line screening test to the evaluation of obese patients presenting with syndromic features. the overall detection rate with the synthetic MLPA probe set was about 5.3% (18 out of 338). Our experience leads us to suggest that MLPA could serve as an effective alternative first line screening test to chromosomal microarrays for diagnosis of syndromic obesity, allowing for a number of loci (e.g., 1p36, 2p25, 2q37, 6q16, 9q34, 11p14, 16p11.2, 17p11.2), known to be clinically relevant for this patient population, to be interrogated simultaneously.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ São Paulo, Inst Biosci, Dept Genet & Evolutionary Biol, Human Genome & Stem Cell Ctr, São Paulo, BrazilUniv São Paulo, Sch Med, Children Inst, Genet Unit,Dept Pediat, São Paulo, BrazilUniv São Paulo, Sch Med, Dept Med Genet, Neurogenet Unit, BR-14049 Ribeirao Preto, BrazilUniversidade Federal de São Paulo, Ctr Med Genet, Dept Morphol, São Paulo, BrazilUniversidade Federal de São Paulo, Ctr Med Genet, Dept Morphol, São Paulo, BrazilFAPESP: 09/52523-1FAPESP: 1998/14254-2CNPq: 304381/2007-1Web of Scienc

Impact of ERT and follow-up of 17 patients from the same family with a mild form of MPS II

Background: Mucopolysaccharidosis type II, also known as Hunter syndrome, is a rare X-linked recessive disorder caused by deficiency of the lysosomal enzyme Iduronate-2- Sulfatase (IDS), leading to progressive accumulation of Glycosaminoglycans (GAGs) in several organs. Over the years, Enzyme Replacement Therapy (ERT) has provided significant benefits for patients, retarding the natural progression of the disease. Results: The authors evaluated 17 patients from the same family with a mild form of MPS type II; the proband had developed acute decompensated heart failure refractory to clinical measurements at 23 years and needed a rather urgent heart transplant; however, he died from surgical complications shortly after the procedure. Nevertheless, subsequent to his tragic death, 16 affected male relatives were detected after biochemical tests identifying the low or absent activity of the IDS enzyme and confirmed by molecular analysis of the IDS gene. Following diagnosis, different options of treatment were chosen: 6 patients started ERT with Elaprase® (Idursulfase) soon after, while the other 10 remained without ERT. Eventually, 4 patients in the latter group began ERT with Hunterase® (Idursulfase Beta). None presented adverse effects to either form of the enzyme. Among the 6 individuals without any ERT, two died of natural causes, after reaching 70 years. Despite the variable phenotype within the same family (mainly heart dysfunctions and carpal tunnel syndrome), all 14 remaining patients were alive with an independent lifestyle. Conclusion: Here, the authors report the variable progress of the disease with and without ERT in a large Brazilian family with a slowly progressive form of MPS II, harboring the same missense variant in the IDS gene

Extending the Phenotype of Monosomy 1p36 Syndrome and Mapping of a Critical Region for Obesity and Hyperphagia

Rearrangements of 1p36 are the most frequently detected abnormalities in diagnostic testing for chromosomal cryptic imbalances and include variably sized simple terminal deletions, derivative chromosomes, interstitial deletions, and complex rearrangements. These rearrangements result in the specific pattern of malformation and neurodevelopmental disabilities that characterizes monosomy 1p36 syndrome. Thus far, no individual gene within this region has been conclusively determined to be causative of any component of the phenotype. Nor is it known if the rearrangements convey phenotypes via a haploinsufficiency mechanism or through a position effect. We have used multiplex ligation-dependent probe amplification to screen for deletions of 1p36 in a group of 154 hyperphagic and overweight/obese, PWS negative individuals, and in a separate group of 83 patients initially sent to investigate a variety of other conditions. the strategy allowed the identification and delineation of rearrangements in nine subjects with a wide spectrum of clinical presentations. Our work reinforces the association of monosomy 1p36 and obesity and hyperphagia, and further suggests that these features may be associated with non-classical manifestations of this disorder in addition to a submicroscopic deletion of similar to 2-3 Mb in size. Multiplex ligation probe amplification using the monosomy 1p36 syndrome-specific kit coupled to the subtelomeric kit is an effective approach to identify and delineate rearrangements at 1p36. (C) 2009 Wiley-Liss, Inc.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ São Paulo, Inst Biociencias, Dept Genet & Evolutionary Biol, BR-05508900 São Paulo, BrazilUniv São Paulo, Dept Pediat, Genet Unit, Children Inst,Sch Med, BR-05508900 São Paulo, BrazilUniv São Paulo, Dept Med Genet, Sch Med, Neurogenet Unit, BR-14049 Ribeirao Preto, BrazilFAPESP: 04/10380-6FAPESP: 1998/14254-2CNPq: 304381/2007-1Web of Scienc

Estudo de soluções de difusão e radiação para a climatização de uma carruagem de comboio

Trabalho final de mestrado para obtenção do grau de Mestre em Engenharia MecânicaA climatização tem ganho maior importância nos novos projetos de carruagens de materiais circulantes visto que uma das principais queixas dos passageiros é a má climatização das mesmas. No entanto a falta de informação sobre este tema ainda é muito elevada tornando este trabalho mais desafiante. A climatização dos transportes ferroviários é feita com recurso a sistemas de climatização de expansão direta utilizando um fluido refrigerante como permutador de calor entre o meio a climatizar e o espaço exterior. Após a produção de calor, ou frio, é necessário definir-se qual o meio de transmitir esse calor para o meio ambiente, para isso é utilizado vários tipos de difusores, variando a velocidade de insuflação e o jato de ar insuflado. Com isso é necessária uma seleção minuciosa de modo a obter o melhor conforto térmico. O presente projeto teve como foco estudar e entender qual o melhor sistema de difusão de ar para a climatização de uma carruagem. Para obter-se uma conclusão foi necessário o estudo e determinação das cargas térmicas para, deste modo, calcular-se os caudais de insuflação necessários. Para a realização do cálculo das cargas foi utilizado o programa DesignBuilder. Outro objetivo foi o estudo do aquecimento por um sistema misto, entre aquecimento por radiação e por difusão de ar. Para determinar-se a melhor solução de difusão de ar realizou-se vários estudos CFD (Computação em Dinâmica dos Fluidos), com recurso ao mesmo programa utilizado para o cálculo das cargas térmicas tendo sido possível observar que o melhor resultado obteve-se quando a difusão de ar foi feita por meio de três difusores de teto. Dois deles, situados por cima da fila de passageiros adjacente ao corredor, com um fluxo unidirecional descendente e o outro difusor situado no centro do teto com fluxo de ar bidirecional. Concluiu-se, igualmente, que a utilização de aquecimento radiante, com a conjunção de um sistema de difusão de ar, melhora o conforto térmico diminuindo o grau de insatisfação dos passageiros.Air conditioning has gained a great importance in the new design projects for rail vehicles carriages, once one of the main complaints of passengers is poor air conditioning. However, the lack of information on this topic is still very high, making this work more challenging. The air conditioning made by rail transport is made using direct expansion air conditioning systems using a refrigerant fluid as a heat exchanger between the air conditioning medium and the outside space. After the production of heat, or cold, it is necessary to define which means of transmitting this heat to the environment, for this it is used several types of diffusers, varying the insufflation speed and the inflated air jet. Therefore, a thorough selection is necessary in order to obtain the best thermal comfort. The present project focused on studying and understanding the best air diffusion system for the air conditioning of a coach in Copenhagen, Denmark. To reach a conclusion, it was necessary to study and determine the heat loads in order to calculate the required insufflation rates. Another objective was the study of heating by a mixed system, between heating by radiation and by air diffusion. With this, it was possible to observe that the best result was obtained when the air diffusion was made through three ceiling diffusers. Two of them, located above the passenger row adjacent to the corridor, with a unidirectional downward flow and the other diffuser located in the center of the ceiling with bidirectional air flow. It was also concluded that the use of radiant heating, namely floor and side panels, improves thermal comfort by reducing the degree of passenger dissatisfaction.N/

Additional file 4: Table S4. of Chromosomal microarray analysis in the genetic evaluation of 279 patients with syndromic obesity

Evaluation of the level of obesity in 208 children and adolescents with BMI ≥ 95th percentile. (PDF 81 kb

Chromosomal microarray analysis in the genetic evaluation of 279 patients with syndromic obesity

Abstract Background Syndromic obesity is an umbrella term used to describe cases where obesity occurs with additional phenotypes. It often arises as part of a distinct genetic syndrome with Prader-Willi syndrome being a classical example. These rare forms of obesity provide a unique source for identifying obesity-related genetic changes. Chromosomal microarray analysis (CMA) has allowed the characterization of new genetic forms of syndromic obesity, which are due to copy number variants (CNVs); however, CMA in large cohorts requires more study. The aim of this study was to characterize the CNVs detected by CMA in 279 patients with a syndromic obesity phenotype. Results Pathogenic CNVs were detected in 61 patients (22%) and, among them, 35 had overlapping/recurrent CNVs. Genomic imbalance disorders known to cause syndromic obesity were found in 8.2% of cases, most commonly deletions of 1p36, 2q37 and 17p11.2 (5.4%), and we also detected deletions at 1p21.3, 2p25.3, 6q16, 9q34, 16p11.2 distal and proximal, as well as an unbalanced translocation resulting in duplication of the GNB3 gene responsible for a syndromic for of childhood obesity. Deletions of 9p terminal and 22q11.2 proximal/distal were found in 1% and 3% of cases, respectively. They thus emerge as being new putative obesity-susceptibility loci. We found additional CNVs in our study that overlapped with CNVs previously reported in cases of syndromic obesity, including a new case of 13q34 deletion (CHAMP1), bringing to 7 the number of patients in whom such defects have been described in association with obesity. Our findings implicate many genes previously associated with obesity (e.g. PTBP2, TMEM18, MYT1L, POU3F2, SIM1, SH2B1), and also identified other potentially relevant candidates including TAS1R3, ALOX5AP, and GAS6. Conclusion Understanding the genetics of obesity has proven difficult, and considerable insight has been obtained from the study of genomic disorders with obesity associated as part of the phenotype. In our study, CNVs known to be causal for syndromic obesity were detected in 8.2% of patients, but we provide evidence for a genetic basis of obesity in as many as 14% of cases. Overall, our results underscore the genetic heterogeneity in syndromic forms of obesity, which imposes a substantial challenge for diagnosis

Deletion 5q12: Delineation of a Phenotype Including Mental Retardation and Ocular Defects

Array-CGH enables the detection of submicroscopic chromosomal deletions and duplications and leads to an accurate delineation of the imbalances, raising the possibility of correlating genotype to phenotype and mapping minimal critical regions associated with particular patterns of clinical features. We report here on four patients sharing common clinical features (psychomotor retardation, coarse facies and ocular anomalies), with proximal 5q deletions identified by oligo array-CGH. The deletions range from 5.75 to 17.26-Mb in size and occurred de novo. A common 2.63-Mb region between the deletions described here can be defined in 5q12.1 (59,390,122-62,021,754 bp bp from 5pter, hg18) and includes 12 genes. Among them, KIF2A, which encodes a kinesin superfamily protein, is a particularly interesting candidate for the phenotype, as it suppresses the growth of axonal collateral branches and is involved in normal brain development. Ocular defects, albeit unspecific, seem to be common in the 5q12.1 deletion. Identification of additional cases of deletions involving the 5q12.1 region will allow more accurate genotype-phenotype correlations. (C) 2011 Wiley-Liss, Inc