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101.
102.
ETV6-RUNX1 (E/R) fusion gene, arising in utero from translocation t(12;21)(p13:q22), is the most frequent alteration in childhood acute lymphoblastic leukemia (ALL). However, E/R is insufficient to cause overt leukemia since it generates a clinically silent pre-leukemic clone which persists in the bone marrow but fails to out-compete normal progenitors. Conversely, pre-leukemic cells show increased susceptibility to transformation following additional genetic insults. Infections/inflammation are the most accredited triggers for mutations accumulation and leukemic transformation in E/R+ pre-leukemic cells. However, precisely how E/R and inflammation interact in promoting leukemia is still poorly understood. Here we demonstrate that IL6/TNFα/ILβ pro-inflammatory cytokines cooperate with BM-MSC in promoting the emergence of E/R+ Ba/F3 over their normal counterparts by differentially affecting their proliferation and survival. Moreover, IL6/TNFα/ILβ-stimulated BM-MSC strongly attract E/R+ Ba/F3 in a CXCR2-dependent manner. Interestingly, E/R-expressing human CD34+IL7R+ progenitors, a putative population for leukemia initiation during development, were preserved in the presence of BM-MSC and IL6/TNFα/ILβ compared to their normal counterparts. Finally, the extent of DNA damage increases within the inflamed niche in both control and E/R-expressing Ba/F3, potentially leading to transformation in the apoptosis-resistant pre-leukemic clone. Overall, our data provide new mechanistic insights into childhood ALL pathogenesis.  相似文献   
103.
Diamond–Blackfan anaemia (DBA) is a rare and heterogeneous disease characterised by hypoplastic anaemia, congenital anomalies and a predisposition for malignancies. The aim of this paper is to report the findings from the Italian DBA Registry, and to discuss the Registry’s future challenges in tackling this disease. Our 20-year long work allowed the connection of 50 Italian Association of Paediatric Haematology and Oncology (AIEOP) centres and the recruitment of 283 cases. Almost all patients have been characterised at a molecular level (96%, 271/283), finding a causative mutation in 68% (184/271). We confirm the importance of determination of erythrocyte adenosine deaminase activity (eADA) and of ribosomal RNA assay in the diagnostic pipeline and characterisation of a remission state. Patients with mutations in large ribosomal subunit protein (RPL) genes had a significant correlation with the incidence of malformations, higher eADA levels and more severe outcomes, compared to patients with mutations in small ribosomal subunit protein (RPS) genes. Furthermore, as a consequence of our findings, particularly the incidence of malignancies and the high percentage of patients aged >18 years, we stress the importance of collaboration with adult clinicians to guarantee regular multi-specialist follow-up. In conclusion, this study highlights the importance of national registries to increase our understanding and improve management of this complex disease.  相似文献   
104.
Objectives

To analyze the potential of human dental pulp stem cells (hDPSCs) for maintaining their undifferentiated status and osteogenic differentiation capacity when arranged in cell sheets (CSs) for future application in bone replacement.

Materials and methods

CSs were formed after being induced for 10–15 days by clonogenic medium containing additional vitamin C (20 μg/ml). The cell viability of hDPSC4s in the CSs was followed until 96 h using the Live/Dead® assay. The cells of the CSs were enzymatically dissociated and then compared with the original hDPSC4s. The two cell types were characterized immunophenotypically by flow cytometry using specific mesenchymal stem cell-associated markers (CD105, CD146, CD44, STRO-1, and OCT3/4) and non-associated markers (CD34, CD45, and CD14). Osteogenic differentiation was analyzed with the Alizarin red assay.

Results

Living cells were observed until 96 h in the CSs. Both cell types exhibited osteogenic differentiation and expressed the specific undifferentiated MSC-associated markers. Cells spontaneously detached from the CSs attached and proliferated at the bottom of the culture dishes.

Conclusions

Cells in the hDPSC4s cell sheets survived for at least 96 h. Moreover, the cells in the cell sheets retained their stemness and their osteogenic differentiation potential.

Clinical relevance

Cell sheets of hDPSCs could be employed as natural tri-dimensional structures for treating bone loss. This technique would be useful particularly for critical bone defects or any type of bone defects in patients carrying diseases that impair bone regeneration, such as diabetes mellitus, medication-related osteonecrosis of the jaw (MRONJ), and osteoporosis.

  相似文献   
105.
106.
Recent evidence reveals that inter- and intra-individual variability significantly affects cognitive performance in a number of neuropsychological pathologies. We applied a flexible family of statistical models to elucidate the contribution of inter- and intra-individual variables on cognitive functioning in healthy volunteers and patients at risk for hepatic encephalopathy (HE). Sixty-five volunteers (32 patients with cirrhosis and 33 healthy volunteers) were assessed by means of the Inhibitory Control Task (ICT). A Generalized Additive Model for Location, Scale and Shape (GAMLSS) was fitted for jointly modeling the mean and the intra-variability of Reaction Times (RTs) as a function of socio-demographic and task related covariates. Furthermore, a Generalized Linear Mixed Model (GLMM) was fitted for modeling accuracy. When controlling for the covariates, patients without minimal hepatic encephalopathy (MHE) did not differ from patients with MHE in the low-demanding condition, both in terms of RTs and accuracy. Moreover, they showed a significant decline in accuracy compared to the control group. Compared to patients with MHE, patients without MHE showed faster RTs and higher accuracy only in the high-demanding condition. The results revealed that the application of GAMLSS and GLMM models are able to capture subtle cognitive alterations, previously not detected, in patients’ subclinical pathologies.  相似文献   
107.

Background

The TNM Classification of Malignant Tumours (TNM) staging system is the primary means of determining a prognosis for gastric adenocarcinoma (GC). However, tumor behavior in the individual patient is unpredictable and in spite of treatment advances, a classification of 'advanced stage' still portends a poor prognosis. Thus, further insights from molecular analyses are needed for better prognostic stratification and determination of new therapeutic targets.

Methods

A total of fifty-one fresh frozen tumor samples from patients with histopathologically confirmed diagnoses of GC, submitted to surgery with curative intent, were included in the study. Total RNA was extracted from an initial group of fifteen samples matched for known prognostic factors, categorized into two subgroups, according to patient overall survival: poor (<24 months) or favorable (at or above 24 months), and hybridized to Affymetrix Genechip human genome U133 plus 2.0 for genes associated with prognosis selection. Thirteen genes were selected for qPCR validation using those initial fifteen samples plus additional thirty-six samples.

Results

A total of 108 genes were associated with poor prognosis, independent of tumor staging. Using systems biology, we suggest that this panel reflects the dampening of immune/inflammatory response in the tumor microenvironment level and a shift to Th2/M2 activity. A gene trio (OLR1, CXCL11 and ADAMDEC1) was identified as an independent marker of prognosis, being the last two markers validated in an independent patient cohort.

Conclusions

We determined a panel of three genes with prognostic value in gastric cancer, which should be further investigated. A gene expression profile suggestive of a dysfunctional inflammatory response was associated with unfavorable prognosis.  相似文献   
108.
Request and emblematic gestures, despite being both communicative gestures, do differ in terms of social valence. Indeed, only the former are used to initiate/maintain/terminate an actual interaction. If such a difference is at stake, a relevant social cue, i.e. eye contact, should have different impacts on the neuronal underpinnings of the two types of gesture. We measured blood oxygen level‐dependent signals, using functional magnetic resonance imaging, while participants watched videos of an actor, either blindfolded or not, performing emblems, request gestures, or meaningless control movements. A left‐lateralized network was more activated by both types of communicative gestures than by meaningless movements, regardless of the accessibility of the actor's eyes. Strikingly, when eye contact was taken into account as a factor, a right‐lateralized network was more strongly activated by emblematic gestures performed by the non‐blindfolded actor than by those performed by the blindfolded actor. Such modulation possibly reflects the integration of information conveyed by the eyes with the representation of emblems. Conversely, a wider right‐lateralized network was more strongly activated by request gestures performed by the blindfolded than by those performed by the non‐blindfolded actor. This probably reflects the effect of the conflict between the observed action and its associated contextual information, in which relevant social cues are missing.  相似文献   
109.
110.
We applied reverse phase protein microarrays technology to map signal pathway interactions in a discovery set of 34 soft tissue sarcoma (STS) bone metastases compared to healthy bone. Proteins associated with matrix remodeling (MMP), adhesion (FAK Y576/577, Syndecan-1), and growth/survival (IGF1R Y1135/1136, PI3K, EGFR) were elevated in metastasis compared to normal bone. Linkage between Syndecan-1, FAK Y576/577, Shc Y317, and EGFR, IGF Y1135/1136, PI3K/AKT was a prominent feature of STS bone metastasis. Elevated linkage between RANKL and 4EBP1 T37/46, EGFR, IGF1R Y1135/1136, Src Y41, Shc Y317, PI3Kp110γ was associated with short survival. Finally, we tested the hypothesis that signal pathway proteins augmented in the STS bone metastasis may provide clues to understand the subset of primary STS that metastasize. The most representative molecules identified in the discovery set were validated on an independent series of 82 primary STS by immunohistochemistry applied to a tissue microarray. The goal was to correlate the molecular profile in the primary tumors with a higher likelihood of metastasis. Elevation of activated kinase substrate endpoints IRS1 S612, 4EBP1 T37/46, FAK Y576/577 and loss of Fibronectin, were associated with a higher likelihood of metastases. These data indicate that the linkage between matrix remodeling, adhesion, and growth signaling may drive STS metastasis and can be the basis for prognostic and therapeutic strategies.  相似文献   
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