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"Degenerative" aortic valve stenosis appears to be a chronic inflammatory process associated with atherosclerotic risk factors. The coexistence of neoangiogenesis, T-lymphocyte infiltration, adhesion molecules, and hsp60 gene expression indicates an active immunomediated process in the final phases of the disease.

Rett syndrome (RTT) is a progressive neurologic disorder representing one of the most common causes of mental retardation in females. To date mutations in three genes have been associated with this condition. Classic RTT is caused by mutations in the MECP2 gene, whereas variants can be due to mutations in either MECP2 or FOXG1 or CDKL5. Mutations in CDKL5 have been identified both in females with the early onset seizure variant of RTT and in males with X-linked epileptic encephalopathy. CDKL5 is a kinase protein highly expressed in neurons, but its exact function inside the cell is unknown. To address this issue we established a human cellular model for CDKL5-related disease using the recently developed technology of induced pluripotent stem cells (iPSCs). iPSCs can be expanded indefinitely and differentiated in vitro into many different cell types, including neurons. These features make them the ideal tool to study disease mechanisms directly on the primarily affected neuronal cells. We derived iPSCs from fibroblasts of one female with p.Q347X and one male with p.T288I mutation, affected by early onset seizure variant and X-linked epileptic encephalopathy, respectively. We demonstrated that female CDKL5-mutated iPSCs maintain X-chromosome inactivation and clones express either the mutant CDKL5 allele or the wild-type allele that serve as an ideal experimental control. Array CGH indicates normal isogenic molecular karyotypes without detection of de novo CNVs in the CDKL5-mutated iPSCs. Furthermore, the iPS cells can be differentiated into neurons and are thus suitable to model disease pathogenesis in vitro. INTRODUCTIONRett syndrome (RTT) is a progressive neurological disorder that affects 1 in 10 000 girls worldwide and represents one of the most common causes of mental retardation in females. RTT is characterized by an apparently normal development for the first 6-18 months of life, followed by regression with the onset of clinical signs including mental retardation, loss of speech, acquired microcephaly, growth retardation, autistic features, seizures, ataxia and hand stereotypies. 1 Beside the classic form, several RTT variants have been described including the Zappella variant, the congenital form, the 'forme fruste' and the early onset seizures variant. [2][3][4][5] In past years, mutations in three genes have been associated with classic and/or variant RTT: MECP2 and CDKL5, located on the X chromosome, and FOXG1, on chromosome 14. 1,6,7 About 80% of classic RTT cases are caused by mutations in MECP2 that encodes for a methyl-CpG-binding protein involved in the regulation of gene expression. 8,9 To investigate the molecular mechanisms leading from MECP2 mutations to RTT onset, different mouse models have been generated and extensively characterized. 10-13 These models allowed identification of specific alterations in glutamatergic neurons: 13 cells lacking Mecp2 have reduced synapse numbers and, accordingly, they show a reduced synaptic response. The opposite effects are elicited by Mecp2 over-expression....

Alport syndrome (ATS) is a hereditary nephropathy often associated with sensorineural hypoacusis and ocular abnormalities. Mutations in the COL4A5 gene cause X-linked ATS. Mutations in COL4A4 and COL4A3 genes have been reported in both autosomal recessive and autosomal dominant ATS. The conventional mutation screening, performed by DHPLC and/or Sanger sequencing, is time-consuming and has relatively high costs because of the absence of hot spots and to the high number of exons per gene: 51 (COL4A5), 48 (COL4A4) and 52 (COL4A3). Several months are usually necessary to complete the diagnosis, especially in cases with less informative pedigrees. To overcome these limitations, we designed a next-generation sequencing (NGS) protocol enabling simultaneous detection of all possible variants in the three genes. We used a method coupling selective amplification to the 454 Roche DNA sequencing platform (Genome Sequencer junior). The application of this technology allowed us to identify the second mutation in two ATS patients (p.Ser1147Phe in COL4A3 and p.Arg1682Trp in COL4A4) and to reconsider the diagnosis of ATS in a third patient. This study, therefore, illustrates the successful application of NGS to mutation screening of Mendelian disorders with locus heterogeneity.