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Neste trabalho foi avaliada a influência do tratamento de fibras de bagaço de cana-de-açúcar nas propriedades mecânicas e dinâmico-mecânicas, na estabilidade térmica, na densidade e absorção de água, quando utilizadas na preparação de compósitos com resinas de poliéster insaturado em comparação com a resina sem reforço. As fibras foram submetidas a tratamento químico com solução alcalina de hidróxido de sódio. O tratamento melhorou as propriedades de impacto, aumentou o módulo de elasticidade em flexão, não alterou significativamente o módulo de elasticidade em tração dos compósitos em relação à resina sem reforço e melhorou a compatibilidade fibra matriz quando comparada com compósitos com a fibra sem tratamento, o que pode ser observado nas fraturas de impacto analisadas por microscopia eletrônica de varredura. As superfícies das fibras também foram avaliadas por microscopia eletrônica de varredura.The aim of this work is to evaluate the influence of the sugar cane bagasse NaOH treatment in the mechanical and dynamic-mechanical properties, in the thermal stability, density and water absorption, when used in unsaturated polyester resin/sugar cane bagasse composite. The sugar cane bagasse was submitted to the chemical treatment with alkaline solution of NaOH. The treatment improves the impact and flexural elasticity modulus when compared with resin without fibers, in addition to the adhesion of the fibers with the matrices, but does not improve significantly the tensile elasticity modulus. The surfaces of the impact fracture were analyzed by SEM.

Our objective is to collect data and information for a better care and follow up in Cri du Chat patients. We conducted a literature review in August 2017 and then discuss the outcomes within the ABC (Associazione Bambini Cri du Chat, Italian CdC families support group). A proposal for clinical, laboratory and imaging work up should be performed at various ages in CdC patients. Follow up and rehabilitation should continue lifelong as some improvements can be obtained also in older ages and not to lose acquired skills., Competing Interests: Conflict of interest: the authors declare no potential conflict of interest.

Background: Recurrent reciprocal 1q21.1 deletions and duplications have been associated with variable phenotypes. Phenotypic features described in association with 1q21.1 microdeletions include developmental delay, craniofacial dysmorphism and congenital anomalies. The 1q21.1 reciprocal duplication has been associated with macrocephaly or relative macrocephaly, frontal bossing, hypertelorism, developmental delay, intellectual disability and autism spectrum disorder., Methods: Our study describes seven patients, who were referred to us for developmental delay/intellectual disability, dysmorphic features and, in some cases, congenital anomalies, in whom we identified 1q21.1 CNVs by array-CGH., Results: Our data confirm the extreme phenotypic variability associated with 1q21.1 microdeletion and microduplication. We observed common phenotypic features, described in previous studies, but we also described, for the first time, congenital hypothyroidism in association with 1q21.1 deletion and trigonocephaly associated with 1q21.1 duplication., Conclusions: The aim of this study is to contribute to the definition of the phenotype associated with reciprocal 1q21.1 deletions and duplications.

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.)

Fanconi anemia is an inherited disease characterized by congenital malformations, pancytopenia, cancer predisposition, and sensitivity to cross-linking agents. The molecular diagnosis of Fanconi anemia is relatively complex for several aspects including genetic heterogeneity with mutations in at least 16 different genes. In this paper, we report the mutations identified in 100 unrelated probands enrolled into the National Network of the Italian Association of Pediatric Hematoly and Oncology. In approximately half of these cases, mutational screening was carried out after retroviral complementation analyses or protein analysis. In the other half, the analysis was performed on the most frequently mutated genes or using a next generation sequencing approach. We identified 108 distinct variants of the FANCA, FANCG, FANCC, FANCD2, and FANCB genes in 85, 9, 3, 2, and 1 families, respectively. Despite the relatively high number of private mutations, 45 of which are novel Fanconi anemia alleles, 26% of the FANCA alleles are due to 5 distinct mutations. Most of the mutations are large genomic deletions and nonsense or frameshift mutations, although we identified a series of missense mutations, whose pathogenetic role was not always certain. The molecular diagnosis of Fanconi anemia is still a tiered procedure that requires identifying candidate genes to avoid useless sequencing. Introduction of next generation sequencing strategies will greatly improve the diagnostic process, allowing a rapid analysis of all the genes., (Copyright© Ferrata Storti Foundation.)

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.)

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.

Purpose: Several studies attempted to clarify the genotype-phenotype correlations in patients with inverted duplication of chromosome 15 [inv dup(15)], which is usually characterized by severe mental retardation and epilepsy in individuals with large duplications including the Prader-Willi/Angelman region. We report two patients with inv dup(15) who, in spite of a large duplication, had a mild phenotype including adult-onset epilepsy. This report may help to define the milder spectrum of the syndrome., Methods: A 25-year-old girl with mild mental retardation had a 6-year history of absence seizures, with occasional head drop. Interictal EEG revealed diffuse spike-wave complexes. Epilepsy was well controlled by a combination of lamotrigine (LTG) and valproate (VPA). The other patient, a 27-year-old man with mild mental retardation, had a 5-year history of rare generalized tonic-clonic seizure during sleep, and frequent episodes of unresponsiveness, which appeared to be atypical absence seizures on video-EEG recordings. A combination of VPA and LTG led to a remarkable improvement, although no complete control., Results: Molecular analysis revealed a large inv dup15 in both patients., Conclusions: The discrepancy between the mild phenotype and the severe chromosomal abnormality detected in these two patients further supports the notion that the site of breakpoint might be contributory to the inv dup(15) phenotype. Inv dup(15) should be considered in atypical cases of generalized epilepsy of adult onset without clear-cut etiology.

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.

The majority of deletions of the short arm of chromosome 5 are associated with cri du chat syndrome (CdCS) and patients show phenotypic and cytogenetic variability. To perform a genotype-phenotype correlation, 80 patients from the Italian CdCS Register were analysed. Molecular cytogenetic analysis showed that 62 patients (77.50%) had a 5p terminal deletion characterised by breakpoint intervals ranging from p13 (D5S763) to p15.2 (D5S18). Seven patients (8.75%) had a 5p interstitial deletion, four (5%) a de novo translocation, and three (3.75%) a familial translocation. Of the remaining four patients, three (3.75%) had de novo 5p anomalies involving two rearranged cell lines and one (1.25%) had a 5p deletion originating from a paternal inversion. The origin of the deleted chromosome 5 was paternal in 55 out of 61 patients (90.2%). Genotype-phenotype correlation in 62 patients with terminal deletions highlighted a progressive severity of clinical manifestation and psychomotor retardation related to the size of the deletion. The analysis of seven patients with interstitial deletions and one with a small terminal deletion confirmed the existence of two critical regions, one for dysmorphism and mental retardation in p15.2 and the other for the cat cry in p15.3. Results from one patient permitted the cat cry region to be distally narrowed from D5S13 to D5S731. Furthermore, this study lends support to the hypothesis of a separate region in p15.3 for the speech delay.

The FRAXE fragile site, 600 kb distal to the more common FRAXA, has been reported to be expressed in subjects with mild non-syndromal mental retardation (MR). Amplification of more than 200 GCC repeats, associated with methylation of the adjacent CpG island at Xq28, leads to the expression of the fragile site. In 1996 a large gene, FMR2, transcribed distally from the CpG island and downregulated by repeat expansion and methylation, was identified. Among 232 mentally retarded patients, tested FRAXA negative, we identified an Italian family segregating a hypermethylated expansion at the FRAXE locus in two dizygotic twin brothers, their sister and their mother. The index case was referred at 23 years of age with severe MR, epilepsy, a dysmorphic face with a high arched palate, marfanoid habitus and hyperreflexia of the lower limbs. His brother was referred to as normal and psychometric tests confirmed he is not mentally retarded. All members of the family underwent FRAXE molecular analysis, after cytogenetic expression of the fraX site and negative FRAXA test. Interestingly, an expansion and a hypermethylation at the FRAXE locus were found in all of them. Fibroblasts from the clinically normal brother were assayed for FMR2 expression and the transcription of the gene was found to be silenced. The presence of a phenotypically normal male with absent FMR2 expression in fibroblasts suggests that the relationship between the FRAXE mutation, FMR2 expression and MR needs to be further investigated.

We report a modified method for the rapid detection of aneuploidies directly on human uncultured amniocytes that simplifies and shortens the entire experimental procedure, yielding signals which allow correct diagnosis of trisomy 21 in 97% of cases. The improvement is based on two points: 1) use of cosmid pockets specific for the Down's syndrome minimal region as FISH probes, and 2) a modified protocol for the fixation and preparation of amniocytes.