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Human term placenta as source of stem cells for regenerative medicine

Abstract

A goal of regenerative medicine is to repair and regenerate damaged cells, tissues, and organs and ultimately restore function. Regeneration can be obtained by cell replacement or by stimulating the body’s own repair mechanisms. It requires a favorable microenvironment so that regenerative signals can stimulate resident stem/stromal cells. Regeneration is only possible after resolution of injury-induced inflammation. Immune response may be aggravated in degenerative, inflammation-based diseases. In this mini-review we discuss how cells isolated from the amniotic membrane of human term placentas and their derivatives, such as conditioned cell culture medium, can help resolve many diseases characterized by altered immune response by acting on different inflammatory mediators. Amniotic cells and derivatives have a wide spectrum of immunomodulatory properties that help trigger tissue regeneration. They can promote resolution of injury-related inflammation by reducing pro-inflammatory signals and favoring anti-inflammatory immune components. The multifaceted, immunomodulatory properties of amniotic membrane-derived cells and derivatives make them attractive for a variety of applications, especially in diseases with an exacerbated immune response, such as degenerative, inflammatory- based diseases.

Open access
Italian experience with Lesch-Nyhan patients and animal models of the disease

Abstract

Lesch-Nyhan Disease (LND) is a rare X-linked genetic disease with hypoxanthine-guanine phosphoribosyltransferase (HGPRT) deficiency, due to mutation in the encoding gene, located on the X-chromosome. LND patients exhibit hyperuricemia with stones due to unrecycled purine accumulation and increased synthesis, and a devastating neurological syndrome with dystonia and self-injurious behaviour, choreoathetosis and spasticity. In spite of biochemical and molecular research, the fine connection between the neurological syndrome and HGPRT deficiency is still unclear, though there is consensus regarding brain neurotransmitter dysfunction with few dopaminergic neuron terminals in the striatum. The rarity of the disease makes it difficult to obtain homogeneous population of patients to study. The aim of this paper is to contribute to the understanding of the connection between genotype and phenotype in a cohort of Italian patients, to propose a reliable method of identifying carrier women in affected families, and to provide evidence of a possible link between HGPRT deficiency and altered adenosinergic and serotonergic neurotransmission. Biochemical and mutation analysis is reported in 28 LNS Italian patients from 25 families, with virtually no HGPRT activity and typical LNS phenotype. Genetic analysis identified 24 HPRT mutations, nine of which had never previously been reported, and no mutation hotspots. Carrier females were identified by a new semiquantitative real-time PCR. Studies performed by real-time PCR on knockout mice demonstrated altered adenosinergic and serotonergic pathways, with greatly increased ADORA1A receptor expression, slightly decreased ADORA2A expression and unchanged ADORA2B expression. Increased HTRC2 expression with no significant difference in mRNA editing suggested serotonergic involvement. The different approaches used allowed us to study certain aspects of LND, focusing on mutation analysis in patients and carriers and on simultaneous analysis of biochemical and genetic features. Mouse models elucidated the possible involvement of adenosine and serotonine receptors in the neurotransmission aberration occurring in HGPRT deficiency.

Open access
MAGI Balkans, a laboratory for the diagnosis of rare genetic diseases

Abstract

Molecular diagnosis relieves patients of uncertainty, aids informed decisions about health and reproductive choices, and helps them join clinical trials or access available therapy. Genetic testing by next generation sequencing (NGS) is the suggested choice for a wide variety of disorders with heterogeneous phenotypes, alleles and loci. The development of a NGS service at MAGI Balkans, through the support of a partner, increases the availability of forefront genetic testing in Albania with great advantages for patients and their families. Here we report the NGS tests performed in collaboration with MAGI Euregio, Italy, for the diagnosis of rare genetic disease in seven probands and their families. The diseases/manifestations included ichthyosis, familial adenomatous polyposis, diabetes, syndromic craniosynostosis, fronto-temporal dementia, fragile X syndrome and ataxia. We obtained an overall detection rate of 57%. For 4/7 probands we identified a pathogenic or likely pathogenic variant, while for the others, the results did not completely explain the phenotype. All variants were confirmed by Sanger sequencing. Segregation of the variant with the affected phenotype was also evaluated.

Open access
Primary lymphedema and genetic implications

Abstract

Primary lymphedema can be familial (in which more than one member of the same family has a lymphedema phenotype), syndromic (in which lymphedema is one symptom of a complex clinical syndrome) or sporadic (in which an isolated family member has lymphedema). All types of lymphedema are determined by genetic alteration of one or more genes. Not all the genes involved are known.

Open access
What is Magi?

Abstract

MAGI is concerned with research and diagnosis of rare genetic diseases. It has been operating since 2006 in Italy and abroad. Today it has three centers in Italy, including a medical genetics laboratory specialized in next generation sequencing in Bolzano, a medical genetics laboratory specialized in MLPA in Rovereto (Trento) and a genetic diseases information center at San Felice del Benaco (Brescia). MAGI has also invested outside Italy, setting up non-profit genetics laboratories in countries such as Albania, Russia and in the near future, Kazakhstan.

Open access
cis- and trans- regulation controls of human meiotic recombination at a hotspot

Abstract

PRDM9 plays a key role in specifying meiotic recombination hotspot locations in humans. To examine the effects of both the 13-bp sequence motif (cis-regulator) and trans-regulator PRDM9 on crossover frequencies and distribution, we studied Hotspot DA. This hotspot had the motif at its centre, and a single nucleotide polymorphism (SNP) that disrupts the motif. The crossover frequency showed Hotspot DA to be a regular hotspot with an average crossover rate (~8 X10-4) among hotspots assayed on autosomes. Our results show that, comparing the rates and distributions of sperm crossover events between donors heterozygous for the disrupting SNP showed that there was a huge asymmetry between the two alleles, with the derived, motif-disrupting allele completely suppressing hotspot activity. Intensive biased gene conversion, both in to crossovers and noncrossovers, has been found at Hotspot DA. Biased gene conversion that influences crossover and non-crossover hotspot activity correlates with PRDM9 allele A. In Hotspot DA, the lifetime of the hotspot mostly depends on the cis-regulatory disrupting SNP, and on the trans-regulatory factor PRDM9. Overall, our observation showed that Hotspot DA is the only evidence for human crossover hotspot regulation by a very strong cisregulatory disrupting SNP.

Open access
Classification of coronary artery disease data sets by using a deep neural network

Abstract

In this study, a deep neural network classifier is proposed for the classification of coronary artery disease medical data sets. The proposed classifier is tested on reference CAD data sets from the literature and also compared with popular representative classification methods regarding its classification performance. Experimental results show that the deep neural network classifier offers much better accuracy, sensitivity and specificity rates when compared with other methods. The proposed method presents itself as an easily accessible and cost-effective alternative to currently existing methods used for the diagnosis of CAD and it can be applied for easily checking whether a given subject under examination has at least one occluded coronary artery or not.

Open access
Extraction, purification and characterization of water soluble galactomannans from Mimosa pudica seeds

Abstract

Water soluble galactomannans from seed endosperm of Mimosa pudica L. was extracted and characterized (Fig. 1). Nuclear magnetic resonance spectroscopy and Gas Chromatography results revealed the presence of 4-linked mannose backbone with galactose side chains linked at the C6 position. Scanning Electron Micrographs showed smooth, elongated and irregular granular structure of galactomannan. Structural analysis by Attenuated total reflection infrared spectroscopy presented the Mannose to Galactose ratio while the X-ray diffraction studies showed the presences of A-type crystalline pattern of the galactomannan. Thermo Gravitimetric Analysis showed the three steps weight loss event and determined the thermal stability. The results showed that the extracted polysaccharides are typically amorphous, thermally stable and have desirable properties for industrial applications.

Open access
Genetic testing for achromatopsia

Abstract

We studied the scientific literature and disease guidelines in order to summarize the clinical utility of genetic testing for achromatopsia. The disease has autosomal recessive inheritance, a prevalence of 1/30000-1/50000, and is caused by mutations in the CNGB3, CNGA3, GNAT2, PDE6C, ATF6 and PDE6H genes. Clinical diagnosis is by ophthalmological examination, color vision testing and electrophysiological testing. Genetic testing is useful for confirming diagnosis and for differential diagnosis, couple risk assessment and access to clinical trials.

Open access
Genetic testing for Bardet-Biedl syndrome

Abstract

We studied the scientific literature and disease guidelines in order to summarize the clinical utility of genetic testing for Bardet- Biedl syndrome (BBS). The disease has autosomal recessive inheritance, a prevalence varying from one in 13 500 to one in 160 000, and is caused by mutations in the ARL6, BBIP1, BBS1, BBS2, BBS4, BBS5, BBS7, BBS9, BBS10, BBS12, CEP290, IFT172, IFT27, LZTFL1, MKKS, MKS1, NPHP1, SDCCAG8, TRIM32, TTC8 and WDPCP genes. The clinical diagnosis of BBS is based on four primary features or three primary features plus two secondary features. The genetic test is useful for confirming diagnosis, and for differential diagnosis, couple risk assessment and access to clinical trials.

Open access