Electroweak Multi-Higgs Production: A Smoking Gun for the Type-I Two-Higgs-Doublet Model.

Extending the Higgs sector of the standard model (SM) by just one additional Higgs doublet field leads to the two-Higgs-doublet model (2HDM). In the type-I Z_{2}-symmetric limit of the 2HDM, all the five new physical Higgs states can be fairly light, O(100) GeV or less, without being in conflict with current data from the direct Higgs boson searches and the B-physics measurements. In this Letter, we establish that the new neutral as well as the charged Higgs bosons in this model can all be simultaneously observable in the multi-b final state. The statistical significance of the signature for each of these Higgs states, resulting from the electroweak (EW) production of their pairs, can exceed 5σ at the 13 TeV high-luminosity Large Hadron collider (HL-LHC). Since the parameter space configurations where this is achievable are precluded in the other, more extensively pursued, 2HDM types, an experimental validation of our findings would be a clear indication that the true underlying Higgs sector in nature is the type-I 2HDM.

Game-theoretic link relevance indexing on genome-wide expression dataset identifies putative salient genes with potential etiological and diapeutics role in colorectal cancer.

Diapeutics gene markers in colorectal cancer (CRC) can help manage mortality caused by the disease. We applied a game-theoretic link relevance Index (LRI) scoring on the high-throughput whole-genome transcriptome dataset to identify salient genes in CRC and obtained 126 salient genes with LRI score greater than zero. The biomarkers database lacks preliminary information on the salient genes as biomarkers for all the available cancer cell types. The salient genes revealed eleven, one and six overrepresentations for major Biological Processes, Molecular Function, and Cellular components. However, no enrichment with respect to chromosome location was found for the salient genes. Significantly high enrichments were observed for several KEGG, Reactome and PPI terms. The survival analysis of top protein-coding salient genes exhibited superior prognostic characteristics for CRC. MIR143HG, AMOTL1, ACTG2 and other salient genes lack sufficient information regarding their etiological role in CRC. Further investigation in LRI methodology and salient genes to augment the existing knowledge base may create new milestones in CRC diapeutics.

Lexicographic solutions for coalitional rankings.

In many real world situations, the design of social rankings over agents or items from a given raking over groups or coalitions, to which these agents or items belong to, is of big interest. With this aim, we revise the lexicographic excellence solution and introduce two novel solutions which, moreover, take into account the size of the groups. We present some desirable axioms which are interpreted in this context. Next, a comparable axiomatization of these three solutions is established, revealing the main differences among the two new social rankings and the lexicographic excellence solution. Finally, we apply the three social rankings under study to a real scenario. Specifically, the performance of some football players of Paris Saint-Germain during the UEFA Champions League according to these three rules is analyzed.

Game theoretic centrality: a novel approach to prioritize disease candidate genes by combining biological networks with the Shapley value.

BACKGROUND: Complex human health conditions with etiological heterogeneity like Autism Spectrum Disorder (ASD) often pose a challenge for traditional genome-wide association study approaches in defining a clear genotype to phenotype model. Coalitional game theory (CGT) is an exciting method that can consider the combinatorial effect of groups of variants working in concert to produce a phenotype. CGT has been applied to associate likely-gene-disrupting variants encoded from whole genome sequence data to ASD; however, this previous approach cannot take into account for prior biological knowledge. Here we extend CGT to incorporate a priori knowledge from biological networks through a game theoretic centrality measure based on Shapley value to rank genes by their relevance-the individual gene's synergistic influence in a gene-to-gene interaction network. Game theoretic centrality extends the notion of Shapley value to the evaluation of a gene's contribution to the overall connectivity of its corresponding node in a biological network. RESULTS: We implemented and applied game theoretic centrality to rank genes on whole genomes from 756 multiplex autism families. Top ranking genes with the highest game theoretic centrality in both the weighted and unweighted approaches were enriched for pathways previously associated with autism, including pathways of the immune system. Four of the selected genes HLA-A, HLA-B, HLA-G, and HLA-DRB1-have also been implicated in ASD and further support the link between ASD and the human leukocyte antigen complex. CONCLUSIONS: Game theoretic centrality can prioritize influential, disease-associated genes within biological networks, and assist in the decoding of polygenic associations to complex disorders like autism.

Identifying the Salient Genes in Microarray Data: A Novel Game Theoretic Model for the Co-Expression Network.

Microarray techniques are used to generate a large amount of information on gene expression. This information can be statistically processed and analyzed to identify the genes useful for the diagnosis and prognosis of genetic diseases. Game theoretic tools are applied to analyze the gene expression data. Gene co-expression networks are increasingly used to explore the system-level functionality of genes, where the roles of the genes in building networks in addition to their independent activities are also considered. In this paper, we develop a novel microarray network game by constructing a gene co-expression network and defining a game on this network. The notion of the Link Relevance Index (LRI) for this network game is introduced and characterized. The LRI successfully identifies the relevant cancer biomarkers. It also enables identifying salient genes in the colon cancer dataset. Network games can more accurately describe the interactions among genes as their basic premises are to consider the interactions among players prescribed by a network structure. LRI presents a tool to identify the underlying salient genes involved in cancer or other metabolic syndromes.

Presence of aggregates of smooth endoplasmic reticulum in MII oocytes affects oocyte competence: molecular-based evidence.

STUDY QUESTION: Does the presence of aggregates of smooth endoplasmic reticulum (SERa) impact the transcriptome of human metaphase II (MII) oocytes?. SUMMARY ANSWER: The presence of SERa alters the molecular status of human metaphase II oocytes. WHAT IS KNOWN ALREADY: Oocytes presenting SERa are considered dysmorphic. Oocytes with SERa (SERa+) have been associated with reduced embryological outcome and increased risk of congenital anomalies, although some authors have reported that SERa+ oocytes can lead to healthy newborns. The question of whether or not SERa+ oocytes should be discarded is still open for debate, and no experimental information about the effect of the presence of SERa on the oocyte molecular status is available. STUDY DESIGN, SIZE, DURATION: This study included 28 women, aged <38 years, without any ovarian pathology, and undergoing IVF treatment. Supernumerary MII oocytes with no sign of morphological alterations as well as SERa+ oocytes were donated after written informed consent. A total of 31 oocytes without SERa (SERa-) and 24 SERa+ oocytes were analyzed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Pools of 8-10 oocytes for both group were prepared. Total RNA was extracted from each pool, amplified, labeled and hybridized on oligonucleotide microarrays. Analyses were performed by R software using the limma package. MAIN RESULTS AND THE ROLE OF CHANCE: The expression profiles of SERa+ oocytes significantly differed from those of SERa- oocytes in 488 probe sets corresponding to 102 down-regulated and 283 up-regulated unique transcripts. Gene Ontology analysis by DAVID bioinformatics disclosed that genes involved in three main biological processes were significantly down-regulated in SERa+ oocytes respective to SERa- oocytes: (i) cell and mitotic/meiotic nuclear division, spindle assembly, chromosome partition and G2/M transition of mitotic cell cycle; (ii) organization of cytoskeleton and microtubules; and (iii) mitochondrial structure and activity. Among the transcripts up-regulated in SERa+ oocytes, the most significantly (P = 0.002) enriched GO term was 'GoLoco motif', including the RAP1GAP, GPSM3 and GPSM1 genes. LARGE SCALE DATA: Raw microarray data are accessible through GEO Series accession number GSE106222 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE106222). LIMITATIONS, REASONS FOR CAUTION: Data validation in a larger cohort of samples would be beneficial, although we applied stringent criteria for gene selection (fold-change >3 or <1/3 and FDR < 0.1). Surveys on clinical outcomes, malformation rates and follow-up of babies born after transfer of embryos from SERa+ oocytes are necessary. WIDER IMPLICATIONS OF THE FINDINGS: We provide information on the molecular status of SERa+ oocytes, highlighting possible associations between presence of SERa, altered oocyte physiology and reduced developmental competence. Our study may offer further information that can assist embryologists to make decisions on whether, and with what possible implications, SERa+ oocytes should be used. We believe that the presence of SERa should be still a 'red flag' in IVF practices and that the decision to inseminate SERa+ oocytes should be discussed on a case-by-case basis. STUDY FUNDING/COMPETING INTEREST(s): This study was partially supported by Ferring Pharmaceuticals. The authors have no conflicts of interest to declare.

An application of the Shapley value to the analysis of co-expression networks.

We study the problem of identifying relevant genes in a co-expression network using a (cooperative) game theoretic approach. The Shapley value of a cooperative game is used to asses the relevance of each gene in interaction with the others, and to stress the role of nodes in the periphery of a co-expression network for the regulation of complex biological pathways of interest. An application of the method to the analysis of gene expression data from microarrays is presented, as well as a comparison with classical centrality indices. Finally, making further assumptions about the a priori importance of genes, we combine the game theoretic model with other techniques from cluster analysis.

[Early and mid-term results of the transapical aortic valve Symetis Acurate TA: a viable solution in high-risk patients with severe vascular disease]. / Risultati a breve e medio termine della valvola aortica transapicale Symetis Acurate TA: valida soluzione nei pazienti vasculopatici ad alto rischio.

BACKGROUND: Aortic valve stenosis is the most common valvular disease in the elderly. Transcatheter aortic valve implantation represents a viable alternative to conventional aortic valve replacement. In our Department, the transapical approach is the preferred method in patients with severe peripheral vascular disease. The aim of this study was to analyze the early and midterm results of Symetis Acurate TA implantation in our series. METHODS: From June 2013 to January 2017, 21 patients with severe peripheral vascular disease (11 male, mean age 78 ± 2.8 years) underwent transapical implantation of the Symetis Acurate TA device. Mean logistic EuroSCORE I was 21.9 ± 8.6, mean left ventricular ejection fraction was 51.9 ± 12.2%, and mean aortic gradient was 46.7 ± 12.3 mmHg. Valve implantation was performed through a left anterior minithoracotomy. Patients were followed up on a regular basis. Cardiac echocardiographic assessment was performed at 6 months post-implantation. RESULTS: Valve implantation was successful in all patients. Valve sizes were as follows: 7 size S, 6 size M, and 8 size L. Two patients died before hospital discharge (9.5%). Among survivors, 2 patients showed more than mild aortic regurgitation at discharge. Mean aortic gradient was 13.1 ± 4.3 mmHg (p<0.01). Median follow-up was 11.3 months. Mean NYHA class at follow-up was 1.9 ± 0.4 (p<0.05). Mean actuarial survival was 80%. CONCLUSIONS: Our series, even if small, demonstrates that transapical implantation of the Symetis Acurate TA device represents a viable solution in patients with severe peripheral vascular disease carrying a high operative risk. The relatively high operative mortality may be attributable to the learning curve of our team.

A genome-wide microRNA profiling indicates miR-424-5p and miR-503-5p as regulators of ALK expression in neuroblastoma.

The discovery of missense mutations of ALK gene identified this receptor tyrosine kinase as a therapeutic target in neuroblastoma (NB). Moreover, a high level of ALK protein has been associated with metastatic NB cases and with a worse prognosis, suggesting that also ALK overexpression is involved in NB tumorigenesis. Since miRNAs play key roles in the regulation of gene expression we aimed at identifying those miRNAs that can regulate ALK in NB. We therefore analyzed the genome-wide expression profile of miRNAs in two sample sets of 16 NB cell lines and 22 NB samples by using miRNA microarrays. Both sample sets were then divided into two subgroups showing high (ALK+) or low/absent (ALK-) expression of ALK. Results showed a down-regulation of 30 and 23 miRNAs (p-value <0.05) in the ALK+ group in NB cell lines and samples, respectively. Validation analysis indicated that miR-424-5p and miR-503-5p, belonging to the same cluster, were differentially expressed in both NB cell lines and tumor samples. Although only miR-424-5p showed a direct binding to ALK 3'-UTR, both miRNAs led to a remarkable decreasing of ALK protein as well as to the inhibition of cell viability in ALK+ NB cell lines. In conclusion, our data indicate that both miR-424-5p and miR-503-5p are involved in regulating ALK expression in NB, either by directly targeting ALK receptor or indirectly, and may thus serve as potential therapeutic tools in ALK dependent NBs.

Safety and efficacy of non-continuous echocardiography-guided pericardiocentesis: a single-center study of 478 patients.

BACKGROUND: There are limited contemporary data on the safety and efficacy of echocardiography-guided pericardiocentesis in Italy. The aim of the study was to evaluate safety and efficacy of pericardiocentesis, performed with non-continuous echocardiography monitoring. All the procedures performed at Department of Cardiovascular Disease, Ospedali Riuniti Ancona, from January 2001 to June 2013, were retrospectively analyzed to determine risks connected to the procedure and its success rate. Epidemiological data, procedure indications and etiology of the effusions were also recorded. METHODS: In the study period, 478 pericardiocentesis were performed for cardiac tamponade (N.=161), to remove large amount of fluid (N.=215) or for diagnostic purposes (N.=102). Echocardiographic evaluation, performed just before the procedure, was used to define the site of entry, to measure the distance from the skin to the fluid, and to establish how to direct the needle. RESULTS: We observed an extremely low rate of complications (<1%), without any death. The procedure was fully successful in 98% of cases and achieved only partial fluid removal in the remained 10 patients. The etiology of the effusion was malignancy or post cardiothoracic surgery in almost 60% of cases. Over the years there was an increase of pericardiocentesis performed after a cardiothoracic surgery (P=0.002); There was a significant reduction of the average amount of drained fluid in the years 2010-2013 vs. the period 2001-2009. CONCLUSIONS: Echocardiography-guided pericardiocentesis is an effective and safe procedure, with a low rate of complications.

Storage time does not modify the gene expression profile of cryopreserved human metaphase II oocytes.

STUDY QUESTION: Does storage time have any impact on the transcriptome of slowly frozen cryopreserved human metaphase II (MII) oocytes? SUMMARY ANSWER: The length of cryostorage has no effect on the gene expression profile of human MII oocytes. WHAT IS KNOWN ALREADY: Oocyte cryopreservation is a widely used technique in IVF for storage of surplus oocytes, as well as for fertility preservation (i.e. women undergoing gonadotoxic therapies) and oocyte donation programs. Although cryopreservation has negative impacts on oocyte physiology and it is associated with decrease of transcripts, no experimental data about the effect of storage time on the oocyte molecular profile are available to date. STUDY DESIGN, SIZE, DURATION: This study included 27 women, ≤38 years aged, without any ovarian pathology, undergoing IVF treatment. Surplus MII oocytes were donated after written informed consent. A total of 31 non-cryopreserved oocytes and 68 surviving slow-frozen/rapid-thawed oocytes (32 oocytes cryostored for 3 years and 36 cryostored for 6 years) were analyzed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Pools of ≈10 oocytes for each group were prepared. Total RNA was extracted from each pool, amplified, labeled and hybridized on oligonucleotide microarrays. Analyses were performed by R software using the limma package. MAIN RESULTS AND THE ROLE OF CHANCE: Comparison of gene expression profiles between surviving thawed oocytes after 3 and 6 years of storage in liquid nitrogen found no differently expressed genes. The expression profiles of cryopreserved MII oocytes significantly differed from those of non-cryopreserved oocytes in 107 probe sets corresponding to 73 down-regulated and 29 up-regulated unique transcripts. Gene Ontology analysis by DAVID bioinformatics resource disclosed that cryopreservation deregulates genes involved in oocyte function and early embryo development, such as chromosome organization, RNA splicing and processing, cell cycle, cellular response to DNA damage and to stress, DNA repair, calcium ion binding, malate dehydrogenase activity and mitochondrial activity. Among the probes significantly up-regulated in cryopreserved oocytes, two corresponded to ovary-specific expressed large intergenic noncoding (linc)RNAs. LIMITATIONS, REASONS FOR CAUTION: Data validation in a larger cohort of samples would be beneficial, although we applied stringent criteria for gene selection (fold-change >3 or <1/3 and FDR < 0.1). Further research should be undertaken to verify experimentally that the length of cryostorage has no effect on gene expression profile of vitrified/warmed MII oocytes, as well as to include in analyses 'older' frozen oocytes. WIDER IMPLICATIONS OF THE FINDINGS: Confirmation that the length of storage does not alter the gene expression profile of frozen oocytes is noteworthy for the safety issue of long-term oocyte banking, i.e. fertility preservation, gamete donation. STUDY FUNDING/COMPETING INTEREST: This study was supported by a grant of the Italian Ministry of Health (CCM 2012) and by Ferring Pharmaceutical company. The authors have no conflicts of interest to declare.

Epigenetic Silencing of DKK3 in medulloblastoma.

Medulloblastoma (MB) is a malignant pediatric brain tumor arising in the cerebellum consisting of four distinct subgroups: WNT, SHH, Group 3 and Group 4, which exhibit different molecular phenotypes. We studied the expression of Dickkopf (DKK) 1-4 family genes, inhibitors of the Wnt signaling cascade, in MB by screening 355 expression profiles derived from four independent datasets. Upregulation of DKK1, DKK2 and DKK4 mRNA was observed in the WNT subgroup, whereas DKK3 was downregulated in 80% MBs across subgroups with respect to the normal cerebellum (p < 0.001). Since copy number aberrations targeting the DKK3 locus (11p15.3) are rare events, we hypothesized that epigenetic factors could play a role in DKK3 regulation. Accordingly, we studied 77 miRNAs predicting to repress DKK3; however, no significant inverse correlation between miRNA/mRNA expression was observed. Moreover, the low methylation levels in the DKK3 promoters (median: 3%, 5% and 5% for promoter 1, 2 and 3, respectively) excluded the downregulation of gene expression by methylation. On the other hand, the treatment of MB cells with Trichostatin A (TSA), a potent inhibitor of histone deacetylases (HDAC), was able to restore both DKK3 mRNA and protein. In conclusion, DKK3 downregulation across all MB subgroups may be due to epigenetic mechanisms, in particular, through chromatin condensation.

High genomic instability predicts survival in metastatic high-risk neuroblastoma.

We aimed to identify novel molecular prognostic markers to better predict relapse risk estimate for children with high-risk (HR) metastatic neuroblastoma (NB). We performed genome- and/or transcriptome-wide analyses of 129 stage 4 HR NBs. Children older than 1 year of age were categorized as "short survivors" (dead of disease within 5 years from diagnosis) and "long survivors" (alive with an overall survival time ≥ 5 years). We reported that patients with less than three segmental copy number aberrations in their tumor represent a molecularly defined subgroup with a high survival probability within the current HR group of patients. The complex genomic pattern is a prognostic marker independent of NB-associated chromosomal aberrations, i.e., MYCN amplification, 1p and 11q losses, and 17q gain. Integrative analysis of genomic and expression signatures demonstrated that fatal outcome is mainly associated with loss of cell cycle control and deregulation of Rho guanosine triphosphates (GTPases) functioning in neuritogenesis. Tumors with MYCN amplification show a lower chromosome instability compared to MYCN single-copy NBs (P = .0008), dominated by 17q gain and 1p loss. Moreover, our results suggest that the MYCN amplification mainly drives disruption of neuronal differentiation and reduction of cell adhesion process involved in tumor invasion and metastasis. Further validation studies are warranted to establish this as a risk stratification for patients.

Age-dependent accumulation of genomic aberrations and deregulation of cell cycle and telomerase genes in metastatic neuroblastoma.

About 50% of children with neuroblastoma (NB) show a metastatic disease and have a poor prognosis. However, disease progression is greatly variable and depends on patients' age and MYCN oncogene amplification. To investigate the role of patients' age in tumor aggressiveness, we performed array-CGH and gene expression profiles of three groups (G) of metastatic NBs: G1, stage 4S patients and MYCN single copy (MYCN-) tumors; G2, stage 4 patients, ≤ 18 months of age, MYCN- tumors and favorable outcome and G3, Stage 4 patients, ≥ 19 months with unfavorable outcome. G1 was characterized by numerical aberrations prevalently; on the contrary, all G3 tumors had structural rearrangements, whereas G2 showed an intermediate pattern. The average of numerical alterations decreased significantly from G1 to G2 to G3 (p < 0.01). Contrarily, the number of structural aberrations increased from G1 to G2 to G3 (p < 2.35 E-05). Noteworthy, G3/MYCN- NBs were characterized by several complex intrachromosome rearrangements. Expression analysis of the three groups showed significant differences in genes of Rho and Ras signaling pathways, development and adhesion, cell cycle regulation and telomerase activity. Accumulation of structural alterations increased with patients' age and was associated with a more aggressive disease. Abnormal expression of genes involved in cell cycle and telomerase in G3 may be responsible for the genomic instability in this cohort of patients. The higher DNA instability observed in G3/MYCN- NBs than in MYCN-amplified G3 may also explain why patients ≥ 19 months have a poor outcome independently by MYCN status.

Bone marrow-infiltrating human neuroblastoma cells express high levels of calprotectin and HLA-G proteins.

Metastases in the bone marrow (BM) are grim prognostic factors in patients with neuroblastoma (NB). In spite of extensive analysis of primary tumor cells from high- and low-risk NB patients, a characterization of freshly isolated BM-infiltrating metastatic NB cells is still lacking. Our aim was to identify proteins specifically expressed by metastatic NB cells, that may be relevant for prognostic and therapeutic purposes. Sixty-six Italian children over 18 months of age, diagnosed with stage 4 NB, were included in the study. Metastatic NB cells were freshly isolated from patients' BM by positive immunomagnetic bead manipulation using anti-GD2 monoclonal antibody. Gene expression profiles were compared with those obtained from archived NB primary tumors from patients with 5 y-follow-up. After validation by RT-qPCR, expression/secretion of the proteins encoded by the up-regulated genes in the BM-infiltrating NB cells was evaluated by flow cytometry and ELISA. Compared to primary tumor cells, BM-infiltrating NB cells down-modulated the expression of CX3CL1, AGT, ATP1A2 mRNAs, whereas they up-regulated several genes commonly expressed by various lineages of BM resident cells. BM-infiltrating NB cells expressed indeed the proteins encoded by the top-ranked genes, S100A8 and A9 (calprotectin), CD177 and CD3, and secreted the CXCL7 chemokine. BM-infiltrating NB cells also expressed CD271 and HLA-G. We have identified proteins specifically expressed by BM-infiltrating NB cells. Among them, calprotectin, a potent inflammatory protein, and HLA-G, endowed with tolerogenic properties facilitating tumor escape from host immune response, may represent novel biomarkers and/or targets for therapeutic intervention in high-risk NB patients.

Bone marrow of neuroblastoma patients shows downregulation of CXCL12 expression and presence of IFN signature.

BACKGROUND: At diagnosis, children with neuroblastoma (NB) present with either localized or metastatic disease. Since the mechanisms responsible for BM invasion are not well known, we investigated the transcriptome of resident BM cells from NB patients as compared to healthy children. PROCEDURE: Ninety-two and 88 children with localized and metastatic NB, respectively, and 15 healthy children were included in the study. BM resident cells recovered from BM aspirates by immunomagnetic bead manipulation were subjected to genome-wide microarray analysis. After validation in an independent set of samples, the genes significantly modulated in resident BM cells from NB patients were tested for their diagnostic/prognostic values. RESULTS: BM resident cells, irrespective of neoplastic cell invasion, significantly overexpressed genes involved in innate immune responses, and interferon (IFN) and IFN-DRS signatures were enriched. Genes coding for metallothioneins and zinc finger proteins, and involved in histone and nucleosome/chromatin organization were also overexpressed. Resident BM cells from NB patients significantly downregulated genes involved in cell adhesion, and in erythrocyte, myeloid, and platelet differentiation pathways. Among downregulated genes, CXCL12 expression reached near complete silencing in patients with metastatic disease. The downregulation of CXCL12 expression was independent of contact between NB cell and resident BM cell. CONCLUSIONS: We demonstrated that NB tumor growth at the primary site can alter the BM microenvironment, and the presence of BM-infiltrating NB cells makes the alterations more pronounced. Therefore, the restoration of a BM physiological state by means of IFN-α monoclonal antibody, Sifalimumab, and selective noradrenaline receptor blockers should be further studied to ameliorate patients' clinical management.

The role of transthoracic echocardiography in the diagnosis and management of acute type A aortic syndrome.

BACKGROUND: Transthoracic echocardiography (TTE) has been traditionally considered inadequate for the diagnosis of acute type A aortic syndrome (AAAS). In the last decade, high-resolution probes and harmonic imaging have been implemented in new echocardiographic systems. However, studies assessing the diagnostic accuracy of TTE for the identification of AAAS in large populations using modern ultrasound technology are lacking. METHODS: The diagnostic value of harmonic imaging TTE was assessed in 270 consecutive patients with suspected AAAS in whom TTE was the initial diagnostic test. RESULTS: Acute type A aortic syndrome was diagnosed in 67 patients and excluded in 203 patients (disease prevalence 25%). Sixty-two patients had a classic acute type A aortic dissection, and 5, an acute type A intramural hematoma. Image quality achieved was considered optimal in 244 patients (90%). In the whole study population, TTE had sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of AAAS of 87%, 91%, 75%, and 95%, respectively. When evaluating only patients with optimal image quality, these values increased to 97%, 100%, 100%, and 99%, respectively. Forty-seven patients with clear-cut evidence of AAAS were transferred immediately to the operative room, where transesophageal echocardiography confirmed the diagnosis obtained by TTE in all patients. CONCLUSIONS: Transthoracic echocardiography is a useful imaging modality for the diagnosis of classic acute type A aortic dissection. It cannot be used as the sole screening technique for detecting AAAS, but in the light of the predictive values observed, patients with optimal image quality and clear-cut diagnosis of AAAS should proceed to the operative room, whereas in patients with negative or indeterminate studies, other imaging techniques are needed to refine the diagnosis.

Gene expression profiling identifies eleven DNA repair genes down-regulated during mouse neural crest cell migration.

Neural Crest Cells (NCCs) are transient multipotent migratory cells that derive from the embryonic neural crest which is itself derived from the margin of the neural tube. DNA repair genes are expressed in the early stages of mammalian development to reduce possible replication errors and genotoxic damage. Some birth defects and cancers are due to inappropriate or defective DNA repair machinery, indicating that the proper functioning of DNA repair genes in the early stages of fetal development is essential for maintaining DNA integrity. We performed a genome-wide expression analysis combining laser capture microdissection (LCM) and high-density oligo-microarray of murine NCCs at pre-migratory embryonic days 8.5 (E8.5), and at E13.5, as well as on neural crest-derived cells from the adrenal medulla at postnatal day 90. We found 11 genes involved in DNA repair activity (response to DNA damage stimulus, DNA damage checkpoint, base-excision repair, mismatch repair), over-expressed in the early stages of mouse embryo development. Expression of these 11 genes was very low or undetectable in the differentiated adrenal medulla of the adult mouse. Amongst the 11 genes, 6 had not been previously reported as being over-expressed during mouse embryonic development. High expression of DNA repair genes in enriched NCCs during early embryonic development may contribute to maintaining DNA integrity whilst failure of some of these genes may be associated with the onset of genetic disease and cancer. Our model of enriched murine NCCs and neural crest-derived cells can be used to elucidate the key roles of genes during normal embryonic development and in cancer pathogenesis.

Identification and quantification of selected inflammatory genes modulated by leflunomide and prednisone treatment in early rheumatoid arthritis patients.

OBJECTIVES: The present study evaluates the effects of combined leflunomide (LEF) and low dose of prednisone therapy, on selected inflammatory gene expression in peripheral blood mononuclear cells (PBMCs) of early rheumatoid arthritis (ERA) patients by gene microarray analysis and quantitative real time-polymerase chain reaction (qRT-PCR). METHODS: Ten ERA patients (mean age 53 ± 10 years) were assigned as untreated (group 1) or pre-treated (group 2) with prednisone (5 mg/day for 3 months) after informed consent and ethics committee approval. Five sex- and age-matched healthy subjects were used as controls (CNT). RNA was extracted by PBMCs, amplified, labelled and hybridised on inflammation DualChip microarray. The expression ratio of 282 inflammatory genes between CNT and ERA patients, before (T0) and after 12 weeks (T1) of combined therapy was detected. qRT-PCR was performed on 7 selected inflammatory RA-related genes (STAT4, MAPK9, HIF1A, MIF, STAT6, NFKB1, TNFRSF1B). RESULTS: At T0, microarray analysis showed 34 altered genes in both ERA groups when compared to CNT (vs. CNT). Seven RA-related genes, investigated in further details, were found up-regulated in group 1 and down-regulated or unchanged in group 2 vs. CNT. At T1, combined therapy induced the down-regulation of these genes in both groups vs. CNT as also confirmed by qRT-PCR performed on selected genes. CONCLUSIONS: Untreated ERA patients seem characterised by up-regulation of specific genes involved both in the resistance/inhibition to apoptosis and in the stimulation of pro-inflammatory cytokine production by immune inflammatory cells. Combined LEF and low dose of prednisone therapy seems to play synergistic effects on down-regulation of these genes.

Using coalitional games on biological networks to measure centrality and power of genes.

MOTIVATION: The interpretation of gene interaction in biological networks generates the need for a meaningful ranking of network elements. Classical centrality analysis ranks network elements according to their importance but may fail to reflect the power of each gene in interaction with the others. RESULTS: We introduce a new approach using coalitional games to evaluate the centrality of genes in networks keeping into account genes' interactions. The Shapley value for coalitional games is used to express the power of each gene in interaction with the others and to stress the centrality of certain hub genes in the regulation of biological pathways of interest. The main improvement of this contribution, with respect to previous applications of game theory to gene expression analysis, consists in a finer resolution of the gene interaction investigated in the model, which is based on pairwise relationships of genes in the network. In addition, the new approach allows for the integration of a priori knowledge about genes playing a key function on a certain biological process. An approximation method for practical computation on large biological networks, together with a comparison with other centrality measures, is also presented.