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101.
102.
A three-dimensional microfluidized liver system to assess hepatic drug metabolism and hepatotoxicity
Brunella Corrado Vincenza De Gregorio Giorgia Imparato Chiara Attanasio Francesco Urciuolo Paolo A. Netti 《Biotechnology and bioengineering》2019,116(5):1152-1163
In this study, we propose the design and fabrication of a liver system on a chip. We first chose the most suitable three-dimensional liver-like model between cell spheroids and microtissue precursors, both based on the use of hepatocellular carcinoma cells (HepG2) to provide proof-of-concept data. Spheroids displayed high cell density but low expression of the typical hepatic biomarkers, whereas microtissue precursors showed stable viability and function over the entire culture time. The two liver-like models were compared in terms of cell viability, function, metabolism, and the P-glycoprotein 1 (P-gp) transport-protein expression with the microtissue precursors showing the best performance. Thus, we cultured them into a microfluidic biochip featured with three parallel channels shaped to mimic the hepatic sinusoids. To assess the detoxification potential of the microtissue-loaded biochip we challenged it with a model molecule (ethanol) at different concentrations and time points. Ethanol cytotoxicity was detected by a noninvasive measurement of cell viability based on cell autofluorescence. As expected, a dose-dependent decrease of albumin and urea secretion was observed in the ethanol-treated samples. We believe that the described totally human-derived platform, suitable for integration into a multiorgan microfluidic system, can provide a consistent innovative platform for drug development and toxicity studies. 相似文献
103.
Revisiting the Thrifty Gene Hypothesis via 65 Loci Associated with Susceptibility to Type 2 Diabetes
104.
105.
Daria Di Sabatino Alessio Lorusso Cristina E. Di Francesco Leonardo Gentile Vincenza Di Pirro Anna Lucia Bellacicco Armando Giovannini Gabriella Di Francesco Giuseppe Marruchella Fulvio Marsilio Giovanni Savini 《PloS one》2014,9(1)
Canine distemper virus (CDV) infection is a primary threat affecting a wide number of carnivore species, including wild animals. In January 2013, two carcasses of Apennine wolves (Canis lupus) were collected in Ortona dei Marsi (L''Aquila province, Italy) by the local Veterinary Services. CDV was immediately identified either by RT-PCR or immunohistochemistry in lung and central nervous tissue samples. At the same time, severe clinical signs consistent with CDV infection were identified and taped (Videos S1–S3) from three wolves rescued in the areas surrounding the National Parks of the Abruzzi region by the Veterinary Services. The samples collected from these symptomatic animals also turned out CDV positive by RT-PCR. So far, 30 carcasses of wolves were screened and CDV was detected in 20 of them. The sequencing of the haemagglutinin gene and subsequent phylogenetic analysis demonstrated that the identified virus belonged to the CDV Arctic lineage. Strains belonging to this lineage are known to circulate in Italy and in Eastern Europe amongst domestic dogs. To the best of our knowledge this is the first report of CDV Arctic lineage epidemics in the wild population in Europe. 相似文献
106.
F Patti A Nicoletti C Leone S Messina E D'Amico S Lo Fermo V Paradisi E Bruno G Quattrocchi P Veroux L Di Pino L Costanzo M Zappia 《PloS one》2012,7(8):e41227
Background
Chronic cerebrospinal venous insufficiency (CCSVI) has been associated to multiple sclerosis (MS).Objective
To evaluate the possible association between CCSVI and MS, using a population-based control design.Methods
A random cohort of 148 incident MS patients were enrolled in the study. We have also studied 20 patients with clinically isolated syndrome (CIS), 40 patients with other neurological diseases (OND), and 172 healthy controls. Transcranial (TCC) and Echo Color Doppler (ECD) were carried out in 380 subjects. A subject was considered CCSVI positive if ≥2 venous hemodynamic criteria were fulfilled.Results
CCSVI was present in 28 (18.9%) of the MS patients, in 2 (10%) of CIS patients, in 11 (6.4%) of the controls, and in 2 (5%) of the OND patients. A significant association between MS and CCSVI was found with an odds ratio of 3.41 (95% confidence interval 1.63–7.13; p = 0.001). CCSVI was significantly more frequent among MS subjects with a disease duration longer than 144 months (26.1% versus 12.6% of patients with duration shorter than 144 months; p = 0.03) and among patients with secondary progressive (SP) and primary progressive (PP) forms (30.2% and 29.4, respectively) than in patients with relapsing remitting (RR) MS (14.3%). A stronger association was found considering SP and PP forms (age adjusted OR = 4.7; 95% CI 1.83–12.0, p = 0.001); the association was weaker with the RR patients (age adjusted OR = 2.58; 95%CI 1.12–5.92; p = 0.02) or not significant in CIS group (age adjusted OR = 2.04; 95%CI 0.40–10.3; p = 0.4).Conclusions
A higher frequency of CCSVI has been found in MS patients; it was more evident in patients with advanced MS, suggesting that CCSVI could be related to MS disability. 相似文献107.
Carrisi C Madeo M Morciano P Dolce V Cenci G Cappello AR Mazzeo G Iacopetta D Capobianco L 《Journal of biochemistry》2008,144(3):389-392
108.
Piazzi L Cavalli A Colizzi F Belluti F Bartolini M Mancini F Recanatini M Andrisano V Rampa A 《Bioorganic & medicinal chemistry letters》2008,18(1):423-426
The complex etiology of Alzheimer's disease (AD) prompts scientists to develop multifunctional compounds to combat causes and symptoms of such neurodegeneration. To this aim we designed, synthesized, and tested a series of compounds by introducing halophenylalkylamidic functions on the scaffold of AP2238, which is a dual binding site acetylcholinesterase inhibitor. The inhibitory activity was successfully extended to the beta-site amyloid precursor protein cleavage enzyme, leading to the discovery of a potent inhibitor of this enzyme (3) and affording multifunctional compounds (2, 6, 8) for the treatment of AD. 相似文献
109.
Two mixed bacterial cultures (CB-BT and CI-AT) degraded phenanthrene when it was: (i) in the presence of either hexadecane as a non aqueous phase liquid or a montmorillonite–Al(OH)x-humic
acid complex as a model organo-mineral matrix; (ii) sorbed to the complex, either alone or in the presence of hexadecane.
The cultures had different kinetic behaviours towards phenanthrene with or without hexadecane. The degradation of Phe alone
as well as that of Phe in hexadecane ended in 8 and 15 days with CB-BT and CI-AT cultures, respectively. Hexadecane increased Phe bioavailability for CI-AT bacteria which degraded Phe according to first-order kinetics. The same effect was observed for CB-BT bacteria, but with an initial 2 days lag phase and in accordance with zero-order kinetics. The presence of hexadecane did
not affect the degradation of phenanthrene sorbed and aged on the complex by CI-AT culture. This capability was exhibited also after experimental aging of 30 days. The dynamics of the bacterial community composition
was investigated through PCR-DGGE (denaturing gradient gel electrophoresis) of 16S rRNA gene fragments. Individual bands changed
their intensity during the incubation time, implying that particular microbe’s relative abundance changed according to the
culture conditions. Isolation of phenanthrene and/or hexadecane degraders was in accord with cultivation-independent data.
Growth-dependent changes in the cell surface hydrophobicity of the two cultures and of the isolates suggested that modulation
of cell surface hydrophobicity probably played an important role for an efficient phenanthrene assimilation/uptake. 相似文献
110.
Dell'Amico E Mazzocchi M Cavalca L Allievi L Andreoni V 《Microbiological research》2008,163(6):671-683
The influence of long-term copper contamination on the diversity of bacterial communities was investigated in an ex-vineyard soil. Two sites of the same area but exhibiting different 3-fold exchangeable copper (Ex-Cu) concentrations were analysed. Culturable bacterial community structure was assessed using a variety of approaches: determination of culturable bacteria number, analyses of 132 isolates, and denaturing gradient gel lectrophoresis (DGGE) patterns of bacterial biomass grown on agar plates and of soil DNA. There was no significant difference in the number of total heterotrophs at the two sites, whereas the percentage of fast-growing bacteria growing in 1 day, was lower at the site with the higher Ex-Cu content. A high percentage of Cu-tolerant bacteria was found in both sites (63-70%) and it was relatively independent of the Cu content. Shifts in species composition of the culturable bacterial community were detected by analysing isolates from the two soils, Gram-positive bacteria prevailed in the less-polluted soil while Gram-negative bacteria in the more-polluted soil. Each sample site had a community with a different metal resistance pattern. Our study seems to indicate that in this soil ecosystem, copper influenced the culturable bacterial communities, affecting the structural diversity and altering some of the metal resistance of the microorganisms. The Sorensen similarity index calculated on DGGE profiles of 16S rDNA of total and culturable bacterial communities indicated a different species composition at the two sites, although both sites had the same biodiversity degree and different dominance. 相似文献