212 research outputs found
Efficacy and epigenetic interactions of novel DNA hypomethylating agent guadecitabine (SGI-110) in preclinical models of hepatocellular carcinoma
Hepatocellular carcinoma (HCC) is a deadly malignancy characterized at the epigenetic level by global DNA hypomethylation and focal hypermethylation on the promoter of tumor suppressor genes. In most cases it develops on a background of liver steatohepatitis, fibrosis, and cirrhosis. Guadecitabine (SGI-110) is a second-generation hypomethylating agent, which inhibits DNA methyltransferases. Guadecitabine is formulated as a dinucleotide of decitabine and deoxyguanosine that is resistant to cytidine deaminase (CDA) degradation and results in prolonged in vivo exposure to decitabine following small volume subcutaneous administration of guadecitabine. Here we found that guadecitabine is an effective demethylating agent and is able to prevent HCC progression in pre-clinical models. In a xenograft HCC HepG2 model, guadecitabine impeded tumor growth and inhibited angiogenesis, while it could not prevent liver fibrosis and inflammation in a mouse model of steatohepatitis. Demethylating efficacy of guadecitabine on LINE-1 elements was found to be the highest 8 d post-infusion in blood samples of mice. Analysis of a panel of human HCC vs. normal tissue revealed a signature of hypermethylated tumor suppressor genes (CDKN1A, CDKN2A, DLEC1, E2F1, GSTP1, OPCML, E2F1, RASSF1, RUNX3, and SOCS1) as detected by methylation-specific PCR. A pronounced demethylating effect of guadecitabine was obtained also in the promoters of a subset of tumor suppressors genes (CDKN2A, DLEC1, and RUNX3) in HepG2 and Huh-7 HCC cells. Finally, we analyzed the role of macroH2A1, a variant of histone H2A, an oncogene upregulated in human cirrhosis/HCC that synergizes with DNA methylation in suppressing tumor suppressor genes, and it prevents the inhibition of cell growth triggered by decitabine in HCC cells. Guadecitabine, in contrast to decitabine, blocked growth in HCC cells overexpressing macroH2A1 histones and with high CDA levels, despite being unable to fully demethylate CDKN2A, RUNX3, and DLEC1 promoters altered by macroH2A1. Collectively, our findings in human and mice models reveal novel epigenetic anti-HCC effects of guadecitabine, which might be effective specifically in advanced states of the disease
Use of particle counter system for the optimization of sampling ,identification and decontamination procedures for biological aerosols dispersion in confined environment
Abstract
In a CBRNe (Chemical, Biological, Radiological, Nuclear and explosive) scenario, biological agents hardly allow
efficient detection/identification because of the incubation time that provides a lag in symptoms outbreak following
their dissemination. The detection of atmospheric dispersion of biological agents (i.e.: toxins, viruses, bacteria and so
on) is a key issue for the safety of people and security of environment. Another fundamental aspect is related to the
efficiency of the sampling method, which leads to the identification of the agent released, in fact an effective sampling
method is needed either to identify the contamination and to check for the decontamination procedure.
Environmental monitoring is one of the ways to improve fast detection of biological agents; for instance, particle
counters with the ability of discriminating between biological and non-biological particles are used for a first warning
when the amount of biological particles exceeds a particular threshold. Nevertheless, these systems are not able to
distinguish between pathogen and non-pathogen organisms, thus, classical “laboratory” assays are still required to
unambiguously identify the particle which triggered the warning signal. In this work, a combination of commercially
available equipment for detection and identification of the atmospheric dispersion of biological agents was evaluated in
partnership between the Italian Army, the Department of Industrial Engineering and the School of Medicine and
Surgery of the University of Rome “Tor Vergata”. The aim of this work, whose results are presented here, was to
conduce preliminary studies on the dynamics of biological aerosols fallout after its dispersion, to improve detection,
sampling and identification techniques. This will help minimizing the impact of the release of biological agents,
guarantee environmental, and people safety and securit
Bridging the demand and the offer in data science
During the last several years, we have observed an exponential increase in the demand for Data Scientists in the job market. As a result, a number of trainings, courses, books, and university educational programs (both at undergraduate, graduate and postgraduate levels) have been labeled as “Big data” or “Data Science”; the fil‐rouge of each of them is the aim at forming people with the right competencies and skills to satisfy the business sector needs. In this paper, we report on some of the exercises done in analyzing current Data Science education offer and matching with the needs of the job markets to propose a scalable matching service, ie, COmpetencies ClassificatiOn (E‐CO‐2), based on Data Science techniques. The E‐CO‐2 service can help to extract relevant information from Data Science–related documents (course descriptions, job Ads, blogs, or papers), which enable the comparison of the demand and offer in the field of Data Science Education and HR management, ultimately helping to establish the profession of Data Scientist.publishedVersio
In vitro antiviral activity of SCH446211 (SCH6), a novel inhibitor of the hepatitis C virus NS3 serine protease.
Current hepatitis C virus (HCV) therapies may cure approximately 60% of infections. They are often contraindicated or poorly tolerated, underscoring the need for safer and more effective drugs. A novel, alpha-ketoamide-derived, substrate-based inhibitor of the HCV serine protease (SCH446211) was developed. Compared with earlier reported inhibitors of similar chemical class, it has a P1'-P2' extension which provides extended interaction with the protease active site. The aim of this study was to evaluate the in vitro antiviral activity of SCH446211.
Binding constant of SCH446211 to HCV NS3 protease was measured with the chromogenic substrate in vitro cleavage assay. Cell-based activity of SCH446211 was evaluated in replicon cells, which are Huh-7 hepatoma cells stably transfected with a subgenomic HCV RNA as reported previously. After 72 h of incubation with SCH446211, viral transcription and protein expression were measured by real-time RT-PCR (TaqMan), quantitative in situ hybridization, immunoblot and indirect immunofluorescence.
The binding constant of SCH446211 to HCV NS3 protease was 3.8 +/- 0.4 nM. HCV replication and protein expression were inhibited by SCH446211 in replicon cells as consistently shown by four techniques. In particular, based on quantitative real-time RT-PCR measurements, the IC50 and IC90 of SCH446211 were estimated to be 40 +/- 20 and 100 +/- 20 nM (n = 17), respectively. Long-term culture of replicon cells with SCH446211 reduced replicon RNA to <0.1 copy per cell. SCH446211 did not show cellular toxicity at concentrations up to 50 microM.
SCH446211 is a potent inhibitor of HCV protease in vitro. Its extended interaction with the HCV NS3 protease active site is associated with potent in vitro antiviral activity. This observation is potentially a useful guide for development of future potent inhibitors against HCV NS3 protease
Early menopause is associated with lack of response to antiviral therapy in women with chronic hepatitis C.
BACKGROUND AND AIMS:
Chronic hepatitis C (CHC) and liver fibrosis progress more rapidly in men and menopausal women than in women of reproductive age. We investigated the associations among menopause, sustained virologic response (SVR), and liver damage in patients with CHC.
METHODS:
We performed a prospective study of 1000 consecutive, treatment-naïve patients 18 years of age and older with compensated liver disease from CHC. Liver biopsy samples were analyzed (for fibrosis, inflammation, and steatosis) before patients received standard antiviral therapy. From women (n = 442), we collected data on the presence, type, and timing of menopause; associated hormone and metabolic features; serum levels of interleukin-6; and hepatic tumor necrosis factor (TNF)-α.
RESULTS:
Postmenopausal women achieved SVRs less frequently than women of reproductive age (46.0% vs 67.5%; P < .0001) but as frequently as men (51.1%; P = .283). By multivariate regression analysis, independent significant predictors for women to not achieve an SVR were early menopause (odds ratio [OR], 8.055; 95% confidence interval [CI], 1.834-25.350), levels of γ-glutamyl transpeptidase (OR, 2.165; 95% CI, 1.364-3.436), infection with hepatitis C virus genotype 1 or 4 (OR, 3.861; 95% CI, 2.433-6.134), and cholesterol levels (OR, 0.985; 95% CI, 0.971-0.998). Early menopause was the only independent factor that predicted lack of an SVR among women with genotype 1 hepatitis C virus infection (OR, 3.933; 95% CI, 1.274-12.142). Baseline levels of liver inflammation, fibrosis, steatosis, serum interleukin-6 (P = .04), and hepatic TNF-α (P = .007) were significantly higher among postmenopausal women than women of reproductive age.
CONCLUSIONS:
Among women with CHC, early menopause was associated with a low likelihood of SVR, probably because of inflammatory factors that change at menopause
Exploring the role of gut microbiota in major depressive disorder and in treatment resistance to antidepressants
Major depressive disorder (MDD) is a common severe psychiatric illness, exhibiting suboptimal response to existing pharmacological treatments. Although its etiopathogenesis is still not completely understood, recent findings suggest that an altered composition of the gut microbiota might play a role. Here we aimed to explore potential differences in the composition of the gut microbiota between patients with MDD and healthy controls (HC) and to identify possible signatures of treatment response by analyzing two groups of MDD patients characterized as treatment-resistant (TR) or responders (R) to antidepressants. Stool samples were collected from 34 MDD patients (8 TR, 19 R and 7 untreated) and 20 HC. Microbiota was characterized using the 16S metagenomic approach. A penalized logistic regression analysis algorithm was applied to identify bacterial populations that best discriminate the diagnostic groups. Statistically significant differences were identified for the families of Paenibacillaceae and Flavobacteriaceaea, for the genus Fenollaria, and the species Flintibacter butyricus, Christensenella timonensis, and Eisenbergiella massiliensis among others. The phyla Proteobacteria, Tenericutes and the family Peptostreptococcaceae were more abundant in TR, whereas the phylum Actinobacteria was enriched in R patients. Moreover, a number of bacteria only characterized the microbiota of TR patients, and many others were only detected in R. Our results confirm that dysbiosis is a hallmark of MDD and suggest that microbiota of TR patients significantly differs from responders to antidepressants. This finding further supports the relevance of an altered composition of the gut microbiota in the etiopathogenesis of MDD, suggesting a role in response to antidepressants
Involvement of gut microbiota in schizophrenia and treatment resistance to antipsychotics
The gut microbiota is constituted by more than 40, 000 bacterial species involved in key processes including high order brain functions. Altered composition of gut microbiota has been implicated in psychiatric disorders and in modulating the efficacy and safety of psychotropic medications. In this work we characterized the composition of the gut microbiota in 38 patients with schizophrenia (SCZ) and 20 healthy controls (HC), and tested if SCZ patients with different response to antipsychotics (18 patients with treatment resistant schizophrenia (TRS), and 20 responders (R)) had specific patterns of gut microbiota composition associated with different response to antipsychotics. Moreover, we also tested if patients treated with typical antipsychotics (n=20) presented significant differences when compared to patients treated with atypical antipsychotics (n=31). Our findings showed the presence of distinct composition of gut microbiota in SCZ versus HC, with several bacteria at the different taxonomic levels only present in either one group or the other. Similar findings were observed also depending on treatment response and exposure to diverse classes of antipsychotics. Our results suggest that composition of gut microbiota could constitute a biosignatures of SCZ and TRS
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