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Brachydactyly type E is a congenital limb malformation characterized by small hands and feet as a result of shortened metacarpals and metatarsals. Genetic causes of this anomaly are heterogeneous and only partially characterized. In this report we describe an Italian family in which four subjects share brachydactyly type E and a 3 Mb microduplication in region 6p25. The duplication involves the gene FOXC1, expressed during the osteoblast differentiation, which appears a potential candidate gene for brachydactyly., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Unlabelled: We report two individuals with developmental delay and dysmorphic features, in whom array-based comparative genomic hybridization (array CGH) led to the identification of a 2p15p16.1 de novo deletion. In the first patient (Patient 1) a familial deletion of 6q12, inherited from her father, was also detected. In the second patient (Patient 2) in addition to the 2p15p16.1 microdeletion a de novo deletion in Xq28 was detected. Both individuals shared dysmorphic features and developmental delay with the six reported patients with a 2p15p16.1 microdeletion described in medical literature., Conclusion: in the first patient a 642 kb 2p16.1 deletion (from 60.604 to 61.246 Mb), and a 930 kb 6q12 familial deletion, was detected and in the second a 2.5 Mb 2p15p16.1 deletion (from 60.258 to 62.763 Mb), with a Xq28 deletion, was discovered. The common dysmorphic features and neurodevelopmental delay found in these patients are in agreement with the clinical phenotype of a microdeletion syndrome involving 2p15p16.1. Our data confirm the hypothesis suggesting that 2p15p16.1 deletion is a contiguous gene syndrome., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

A computer model of pressure response to hemodialysis-induced hypovolemia is reported. Heart rate and hematocrit, measured in the course of hemodialysis, are imposed as computer model inputs and the model computes the arterial pressure response after tuning model parameters representative of patient's cardiovascular reactivity. Computer model reproduced with good accuracy experimental data (arterial pressure, cardiac output and total peripherical resistance). Parameter identification over successive sessions of the same patients revealed satisfactory reliability, providing a physiological interpretative key to patient's hemodynamic behavior during hemodialysis.

Purpose: We evaluated the experiences of 19 Italian laboratories concerning 241 small supernumerary marker chromosomes (sSMCs) with the aim of answering questions arising from their origin from any chromosome, their variable size and genetic content, and their impact on the carrier's phenotype., Methods: Conventional protocols were used to set up the cultures and chromosome preparations. Both commercial and homemade probes were used for the fluorescent in situ hybridization analyses., Results: A total of 113 of the 241 sSMCs were detected antenatally, and 128 were detected postnatally. There were 52 inherited and 172 de novo cases. Abnormal phenotype was present in 137 cases (57%), 38 of which were antenatally diagnosed. A mosaic condition was observed in 87 cases (36%). In terms of morphology, monocentric and dicentric bisatellited marker chromosomes were the most common, followed by monocentric rings and short-arm isochromosomes. The chromosomes generating the sSMCs were acrocentric in 132 cases (69%) and non-acrocentric chromosomes in 60 cases (31%); a neocentromere was hypothesized in three cases involving chromosomes 6, 8, and 15., Conclusion: The presented and published data still do not allow any definite conclusions to be drawn concerning karyotype-phenotype correlations. Only concerted efforts to characterize molecularly the sSMCs associated or not with a clinical phenotype can yield results suitable for addressing karyotype-phenotype correlations in support of genetic counseling.

Transient myeloid disorder is a unique self-regressing neoplasia specific to Down's syndrome. The transcription factor GATA1 is needed for normal growth and maturation of erythroid cells and megakaryocytes. Mutations in GATA1 have been reported in acute megakaryoblastic leukaemia in Down's syndrome. We aimed to investigate changes in GATA1 in patients with Down's syndrome and either transient myeloid disorder (n=10) or acute megakaryoblastic leukaemia (n=6). We recorded mutations eliminating exon 2 from GATA1 in all patients with transient myeloid disorder (age 0-24 days) and in all with acute megakaryoblastic leukaemia (age 14-38 months). The range of mutations did not differ between patients with each disorder. Patients with transient myeloid disorder with mutations in GATA1 can regress spontaneously to complete remission, and mutations do not necessarily predict later acute megakaryoblastic leukaemia.

Background: A large inter-subject variability exists in the arterial pressure response to hemodialysis-induced blood volume (BV) withdrawal. We investigated the hypothesis that this variability is due to the inter-subject differences in the short-term reflex capacity to compensate for hypovolemia., Methods: Mean arterial pressure (MAP), heart rate (HR) and the percentage reduction in BV (%R-BV) were recorded in 32 subjects during their regular hemodialysis sessions. On the basis of absolute MAP changes between the beginning and the end of the session with respect to %R-BV at the end of the session, three distinct pressure responses were identified: (1) hypotension-prone response; (2) unstable response with delayed hypotension; and (3) hypotension-resistant response. For each kind of response, one patient was selected and a computer model of the cardiovascular system including the main short-term reflex compensatory mechanisms was used to analyze data collected over five consecutive sessions. The %R-BV and HR were used as model inputs, while simulated arterial pressure was fitted to the measured MAP by the tuning model parameters representing the efficiency in the control of venous capacity, microvascular resistance and heart inotropism., Results: The model-based analysis related the hypotension-prone response to a lack of efficacy in capacity and resistance regulation. In the unstable response with delayed hypotension, the control of venous capacity was not effective and resistance control alone kept the pressure stable only for a limited %R-BV reduction (<5%). In the hypotension-resistant response, an efficient compensation of capacitance vessels was evidenced, and the slightly increasing arterial pressure was referred to a prevalence of cardiopulmonary pathway in the compensatory process., Conclusions: The model ascribes differences in pressure response to differences in the effectiveness of reflex compensatory mechanisms.