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1.
Phys Rev Lett ; 131(23): 231801, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38134801

RESUMO

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.

2.
BMC Bioinformatics ; 21(1): 356, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32787845

RESUMO

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.


Assuntos
Algoritmos , Teoria dos Jogos , Redes Reguladoras de Genes , Estudos de Associação Genética , Transtorno do Espectro Autista/genética , Estudo de Associação Genômica Ampla , Humanos , Mapeamento de Interação de Proteínas , Reprodutibilidade dos Testes
3.
Mol Hum Reprod ; 24(6): 310-317, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29635518

RESUMO

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.


Assuntos
Retículo Endoplasmático Liso/ultraestrutura , Oócitos/ultraestrutura , Adulto , Análise por Conglomerados , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Oócitos/crescimento & desenvolvimento , Oócitos/fisiologia , Transcriptoma
4.
Hum Reprod ; 30(11): 2519-26, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26385790

RESUMO

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.


Assuntos
Criopreservação/normas , Fertilização in vitro/normas , Expressão Gênica/fisiologia , Metáfase/fisiologia , Oócitos/fisiologia , Adulto , Feminino , Humanos , Fatores de Tempo
5.
Int J Mol Sci ; 14(4): 7492-505, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23567267

RESUMO

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.


Assuntos
Montagem e Desmontagem da Cromatina , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Meduloblastoma/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Linhagem Celular Tumoral , Quimiocinas , Criança , Pré-Escolar , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Meduloblastoma/genética , Meduloblastoma/patologia , Metilação , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese
6.
Int J Cancer ; 131(7): 1591-600, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22234802

RESUMO

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.


Assuntos
Ciclo Celular/genética , Aberrações Cromossômicas , Neuroblastoma/genética , Neuroblastoma/patologia , Telomerase/genética , Fatores Etários , Variações do Número de Cópias de DNA , Amplificação de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genes myc , Humanos , Metástase Neoplásica
7.
Am Heart J ; 163(1): 112-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22172444

RESUMO

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.


Assuntos
Aneurisma Aórtico/diagnóstico por imagem , Dissecção Aórtica/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Hematoma/diagnóstico por imagem , Idoso , Ecocardiografia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Síndrome
8.
Pediatr Blood Cancer ; 59(1): 44-51, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21994039

RESUMO

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.


Assuntos
Neoplasias da Medula Óssea/metabolismo , Medula Óssea/metabolismo , Quimiocina CXCL12/biossíntese , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Interferons/biossíntese , Proteínas de Neoplasias/biossíntese , Neuroblastoma/metabolismo , Adolescente , Medula Óssea/patologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Neoplasias da Medula Óssea/tratamento farmacológico , Neoplasias da Medula Óssea/patologia , Neoplasias da Medula Óssea/secundário , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Itália , Masculino , Metástase Neoplásica , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Sistema de Registros , Estudos Retrospectivos , Microambiente Tumoral
9.
Sci Rep ; 12(1): 13409, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927308

RESUMO

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.


Assuntos
Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Angiomotinas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Perfilação da Expressão Gênica , Humanos , Proteínas de Membrana/metabolismo , Prognóstico , Análise de Sobrevida , Transcriptoma
10.
Bioinformatics ; 26(21): 2721-30, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20817743

RESUMO

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.


Assuntos
Perfilação da Expressão Gênica/métodos , Expressão Gênica , Algoritmos
11.
Clin Exp Rheumatol ; 29(1): 72-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21345295

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Glucocorticoides/uso terapêutico , Isoxazóis/uso terapêutico , Prednisona/uso terapêutico , Fatores de Transcrição/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Artrite Reumatoide/genética , Citocinas/metabolismo , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Perfilação da Expressão Gênica , Humanos , Leflunomida , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sinovite/tratamento farmacológico , Sinovite/genética , Regulação para Cima
12.
Soc Choice Welfare ; 57(4): 817-849, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34121787

RESUMO

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.

13.
Diagnostics (Basel) ; 10(8)2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823765

RESUMO

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.

14.
BMC Cancer ; 9: 441, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20003513

RESUMO

BACKGROUND: Neuroblastoma is the most common, pediatric, extra-cranial, malignant solid tumor. Despite multimodal therapeutic protocols, outcome for children with a high-risk clinical phenotype remains poor, with long-term survival still less than 40%. Hereby, we evaluated the potential of non-coding RNA expression to predict outcome in high-risk, stage 4 neuroblastoma. METHODS: We analyzed expression of 481 Ultra Conserved Regions (UCRs) by reverse transcription-quantitative real-time PCR and of 723 microRNAs by microarrays in 34 high-risk, stage 4 neuroblastoma patients. RESULTS: First, the comparison of 8 short- versus 12 long-term survivors showed that 54 UCRs were significantly (P < 0.0491) over-expressed in the former group. For 48 Ultra Conserved Region (UCRs) the expression levels above the cut-off values defined by ROC curves were strongly associated with good-outcome (OS: 0.0001


Assuntos
Sequência Conservada , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neuroblastoma/genética , Neuroblastoma/terapia , Transcrição Gênica , Sequência de Bases , Pré-Escolar , Humanos , Estadiamento de Neoplasias , Neuroblastoma/patologia , Projetos Piloto , Fatores de Risco , Resultado do Tratamento
15.
BMC Bioinformatics ; 9: 361, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18764936

RESUMO

BACKGROUND: In gene expression analysis, statistical tests for differential gene expression provide lists of candidate genes having, individually, a sufficiently low p-value. However, the interpretation of each single p-value within complex systems involving several interacting genes is problematic. In parallel, in the last sixty years, game theory has been applied to political and social problems to assess the power of interacting agents in forcing a decision and, more recently, to represent the relevance of genes in response to certain conditions. RESULTS: In this paper we introduce a Bootstrap procedure to test the null hypothesis that each gene has the same relevance between two conditions, where the relevance is represented by the Shapley value of a particular coalitional game defined on a microarray data-set. This method, which is called Comparative Analysis of Shapley value (shortly, CASh), is applied to data concerning the gene expression in children differentially exposed to air pollution. The results provided by CASh are compared with the results from a parametric statistical test for testing differential gene expression. Both lists of genes provided by CASh and t-test are informative enough to discriminate exposed subjects on the basis of their gene expression profiles. While many genes are selected in common by CASh and the parametric test, it turns out that the biological interpretation of the differences between these two selections is more interesting, suggesting a different interpretation of the main biological pathways in gene expression regulation for exposed individuals. A simulation study suggests that CASh offers more power than t-test for the detection of differential gene expression variability. CONCLUSION: CASh is successfully applied to gene expression analysis of a data-set where the joint expression behavior of genes may be critical to characterize the expression response to air pollution. We demonstrate a synergistic effect between coalitional games and statistics that resulted in a selection of genes with a potential impact in the regulation of complex pathways.


Assuntos
Poluição do Ar/estatística & dados numéricos , Interpretação Estatística de Dados , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Perfilação da Expressão Gênica/métodos , Proteoma/análise , Medição de Risco/métodos , Algoritmos , Biomarcadores/análise , Criança , Simulação por Computador , República Tcheca/epidemiologia , Métodos Epidemiológicos , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Modelos Biológicos , Modelos Estatísticos , Fatores de Risco
16.
Appl Netw Sci ; 3(1): 35, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30839839

RESUMO

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.

17.
BMC Genomics ; 8: 17, 2007 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17229315

RESUMO

BACKGROUND: The normalization of DNA microarrays allows comparison among samples by adjusting for individual hybridization intensities. The approaches most commonly used are global normalization methods that are based on the expression of all genes on the slide and on the modulation of a small proportion of genes. Alternative approaches must be developed for microarrays where the proportion of modulated genes and their distribution are unknown and they may be biased towards up- or down-modulated trends. RESULTS: The aim of the work is to study the use of spike-in controls to normalize low-density microarrays. Our test-array was designed to analyze gene modulation in response to hypoxia (a condition of low oxygen tension) in a macrophage cell line. RNA was extracted from controls and cells exposed to hypoxia, mixed with spike RNA, labeled and hybridized to our test-array. We used eight bacterial RNAs as source of spikes. The test-array contained the oligonucleotides specific for 178 mouse genes and those specific for the eight spikes. We assessed the quality of the spike signals, the reproducibility of the results and, in general, the nature of the variability. The small values of the coefficients of variation revealed high reproducibility of our platform either in replicated spots or in technical replicates. We demonstrated that the spike-in system was suitable for normalizing our platform and determining the threshold for discriminating the hypoxia modulated genes. We assessed the application of the spike-in normalization method to microarrays in which the distribution of the expression values was symmetric or asymmetric. We found that this system is accurate, reproducible and comparable to other normalization methods when the distribution of the expression values is symmetric. In contrast, we found that the use of the spike-in normalization method is superior and necessary when the distribution of the gene expression is asymmetric and biased towards up-regulated genes. CONCLUSION: We demonstrate that spike-in controls based normalization is a reliable and reproducible method that has the major advantage to be applicable also to biased platform where the distribution of the up- and down-regulated genes is asymmetric as it may occur in diagnostic chips.


Assuntos
Macrófagos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência com Séries de Oligonucleotídeos/normas , RNA/genética , Potenciais de Ação , Animais , Hipóxia Celular , Linhagem Celular , Perfilação da Expressão Gênica , Camundongos , RNA/química , Reprodutibilidade dos Testes , Regulação para Cima
18.
Oncotarget ; 8(34): 56518-56532, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28915608

RESUMO

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.

19.
G Ital Cardiol (Rome) ; 18(10): 727-733, 2017 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-29105687

RESUMO

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.


Assuntos
Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Doenças Vasculares/complicações , Idoso , Feminino , Humanos , Masculino , Desenho de Prótese , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
20.
Minerva Cardioangiol ; 65(5): 451-457, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27901332

RESUMO

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.


Assuntos
Ecocardiografia/métodos , Pericardiocentese/efeitos adversos , Pericardiocentese/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Derrame Pericárdico/epidemiologia , Derrame Pericárdico/etiologia , Estudos Retrospectivos
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