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1.
J Endocrinol Invest ; 2024 Mar 17.
Article in English | MEDLINE | ID: mdl-38493246

ABSTRACT

PURPOSE: As reported in patients treated for androgenetic alopecia with finasteride (i.e., a blocker of the enzyme 5 alpha-reductase) and in an animal model, side effects affecting sexual, psychiatric, neurological, and physical domains, may occur during the treatment and persist with drug suspension. The etiopathogenesis of these side effects has been poorly explored. Therefore, we performed a genome-wide analysis of finasteride effects in the brain of adult male rat. METHODS: Animals were treated (i.e., for 20 days) with finasteride (1mg/rat/day). 24 h after the last treatment and 1 month after drug suspension, RNA sequencing analysis was performed in hypothalamus and hippocampus. Data were analyzed by differential expression analysis and Gene-Set Enrichment Analyses (GSEA). RESULTS: Data obtained after finasteride treatment showed that 186 genes (i.e., 171 up- and 15 downregulated) and 19 (i.e., 17 up- and 2 downregulated) were differentially expressed in the hypothalamus and hippocampus, respectively. Differential expression analysis at the drug withdrawal failed to identify dysregulated genes. Several gene-sets were enriched in these brain areas at both time points. CONCLUSION: Some of the genes reported to be differentially expressed (i.e., TTR, DIO2, CLDN1, CLDN2, SLC4A5, KCNE2, CROT, HCRT, MARCKSL1, VGF, IRF2BPL) and GSEA, suggest a potential link with specific side effects previously observed in patients and in the animal model, such as depression, anxiety, disturbance in memory and attention, and sleep disturbance. These data may provide an important background for future experiments aimed at confirming the pathological role of these genes.

2.
Clin Exp Med ; 24(1): 11, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38244120

ABSTRACT

Polycythemia Vera (PV) is typically caused by V617F or exon 12 JAK2 mutations. Little is known about Polycythemia cases where no JAK2 variants can be detected, and no other causes identified. This condition is defined as idiopathic erythrocytosis (IE). We evaluated clinical-laboratory parameters of a cohort of 56 IE patients and we determined their molecular profile at diagnosis with paired blood/buccal-DNA exome-sequencing coupled with a high-depth targeted OncoPanel to identify a possible underling germline or somatic cause. We demonstrated that most of our cohort (40/56: 71.4%) showed no evidence of clonal hematopoiesis, suggesting that IE is, in large part, a germline disorder. We identified 20 low mutation burden somatic variants (Variant allelic fraction, VAF, < 10%) in only 14 (25%) patients, principally involving DNMT3A and TET2. Only 2 patients presented high mutation burden somatic variants, involving DNMT3A, TET2, ASXL1 and WT1. We identified recurrent germline variants in 42 (75%) patients occurring mainly in JAK/STAT, Hypoxia and Iron metabolism pathways, among them: JAK3-V722I and HIF1A-P582S; a high fraction of patients (48.2%) resulted also mutated in homeostatic iron regulatory gene HFE-H63D or C282Y. By generating cellular models, we showed that JAK3-V722I causes activation of the JAK-STAT5 axis and upregulation of EPAS1/HIF2A, while HIF1A-P582S causes suppression of hepcidin mRNA synthesis, suggesting a major role for these variants in the onset of IE.


Subject(s)
Polycythemia Vera , Polycythemia , Humans , Polycythemia/diagnosis , Polycythemia/genetics , Polycythemia Vera/genetics , Mutation , Iron , Germ Cells
3.
Leukemia ; 37(12): 2383-2394, 2023 12.
Article in English | MEDLINE | ID: mdl-37803061

ABSTRACT

Extramedullary (EM) colonization is a rare complication of acute myeloid leukemia (AML), occurring in about 10% of patients, but the processes underlying tissue invasion are not entirely characterized. Through the application of RNAseq technology, we examined the transcriptome profile of 13 AMLs, 9 of whom presented an EM localization. Our analysis revealed significant deregulation within the extracellular matrix (ECM)-receptor interaction and focal-adhesion pathways, specifically in the EM sites. The transcription factor TWIST1, which is known to impact on cancer invasion by dysregulating epithelial-mesenchymal-transition (EMT) processes, was significantly upregulated in EM-AML. To test the functional impact of TWIST1 overexpression, we treated OCI-AML3s with TWIST1-siRNA or metformin, a drug known to inhibit tumor progression in cancer models. After 48 h, we showed downregulation of TWIST1, and of the EMT-related genes FN1 and SNAI2. This was associated with significant impairment of migration and invasion processes by Boyden chamber assays. Our study shed light on the molecular mechanisms associated with EM tissue invasion in AML, and on the ability of metformin to interfere with key players of this process. TWIST1 may configure as candidate marker of EM-AML progression, and inhibition of EMT-pathways may represent an innovative therapeutic intervention to prevent or treat this complication.


Subject(s)
Leukemia, Myeloid, Acute , Metformin , Humans , Cell Line, Tumor , Epithelial-Mesenchymal Transition/genetics , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , RNA, Small Interfering , Neoplasm Invasiveness/pathology , Gene Expression Regulation, Neoplastic
4.
Eur Rev Med Pharmacol Sci ; 27(2): 799-804, 2023 01.
Article in English | MEDLINE | ID: mdl-36734722

ABSTRACT

OBJECTIVE: To assess the feasibility of a new device for telemonitoring vital parameters during iloprost infusion. MATERIALS AND METHODS: In a pilot study, patients with systemic sclerosis received iloprost infusion while being telemonitored with Umana T1 Heart Monitor, within the hospital, under the supervision of family/community nurses and rheumatologists. Patients were administered a questionnaire to obtain information on satisfaction, practicability, and compliance with the new monitoring device. RESULTS: Data recorded by the device for blood pressure, heart rate, and oximetry were concordant with those registered directly by nurses. Most patients found the device useful and thought it could be used at home, even while working. CONCLUSIONS: Umana Heart Monitor T1 could be a valuable aid in at-home iloprost therapy in patients with systemic sclerosis.


Subject(s)
Iloprost , Scleroderma, Systemic , Humans , Iloprost/therapeutic use , Pilot Projects , Feasibility Studies , Scleroderma, Systemic/drug therapy , Blood Pressure , Vasodilator Agents/therapeutic use
5.
Eur Rev Med Pharmacol Sci ; 26(21): 7967-7973, 2022 11.
Article in English | MEDLINE | ID: mdl-36394746

ABSTRACT

OBJECTIVE: This study aims at evaluating the disease progression, specifically in terms of cardiopulmonary function, in a group of consecutively enrolled systemic sclerosis (SSc) patients treated with the approved iloprost regimen. PATIENTS AND METHODS: A retrospective observational study was performed on 68 SSc patients treated with 5-6 infusions of iloprost per month for 6 hours per day at a dosage of 0.5-2.0 ng/kg/min through a portable syringe pump. All patients were evaluated for modified Rodnan skin score, systolic pulmonary arterial pressure, tricuspid annular plane systolic excursion, diffusing capacity of the lungs for carbon monoxide, forced vital capacity, alveolar volume, diffusing capacity of the lungs for carbon monoxide/alveolar volume, pro-brain natriuretic peptide (pBNP), New York Heart Association class, and the presence or absence of digital ulcers (DUs). RESULTS: After a follow-up period of 9.9±2.9 years, all patients improved in frequency and severity of the Raynaud phenomenon and showed a stabilization or improvement of cardiopulmonary parameters. The pulmonary arterial pressure and pBNP improved significantly from baseline (30.91±6.4 mmHg vs. 27.36±7.1 mmHg, and 97.20±69.3 pg/ml vs. 66.65±44.3 pg/ml, respectively; p<0.0001 for both). A significant improvement was observed in the modified Rodnan skin score in 57 patients who continued the treatment during the entire follow-up (5.09±5.7 vs. 3.30±4.2, p<0.0001). CONCLUSIONS: Despite the retrospective design and the lack of a control group, the regular and continued administration of iloprost maintained the stability of the cardiopulmonary and cutaneous parameters in SSc. It significantly reduced pBNP levels, a prognostic cardiac biomarker of SSc. Future research should be addressed to demonstrate a stronger causality of this effect.


Subject(s)
Raynaud Disease , Scleroderma, Systemic , Humans , Iloprost , Retrospective Studies , Carbon Monoxide , Scleroderma, Systemic/drug therapy
6.
Sci Total Environ ; 801: 149743, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34467913

ABSTRACT

The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection requires the detection of viral RNA by reverse transcription-polymerase chain reaction (RT-qPCR) performed mainly using nasopharyngeal swabs. However, this procedure requires separate analysis per each individual, performed in advanced centralized laboratory facilities with specialized medical personnel. In this study, an alternative approach termed "solid waste-based surveillance (SWBS)" was explored, in order to investigate SARS-CoV-2 infection in small communities through the indirect sampling of saliva left on waste. Sampling was performed at 20 different sites in Italy during the second peak of COVID-19. Three swabs were positive for SARS-CoV-2 using a published RT-qPCR protocol targeting the non-structural protein 14 region, and the viral load ranged 4.8 × 103-4.0 × 106 genome copies/swab. Amino acid substitutions already reported in SARS-CoV-2 sequences circulating in Italy (A222V and P521S) were detected in two positive samples. These findings confirmed the effectiveness of SWBS for non-invasive and dynamic SARS-CoV-2 surveillance.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Nasopharynx , Solid Waste , Specimen Handling
7.
J Microbiol Methods ; 175: 105965, 2020 08.
Article in English | MEDLINE | ID: mdl-32497660

ABSTRACT

The latex agglutination test using single-chain antibody fragments (scFvStx1 and scFvStx2) coupled to latex particles, was compared with the gold standard Vero cell assay for Shiga toxin (Stx) detection, aiming to estimate the diagnosis potential of these scFv fragments in a rapid and straightforward test. The latex complexes identified the presence of the toxins up to a 1:8 dilution in the majority of the evaluated strains. Moreover, the Stx concentration was indirectly determined in Stx-producing Escherichia coli (STEC) strains, allowing detection limit inference. A Stx dilution curve was constructed, and the data was analyzed in a non-linear model by second-order polynomial regression for prediction (p-value of 0.001 and a R2 above 0.98 were considered for correlations). The detection limit was 30 ng/mL for Stx1 and 10 ng/mL for Stx2. The scFvStx1 and scFvStx2 coupled to latex nanoparticles provide a toxin assay with a competitive Stx detection limit, which has a low cost and short execution time. The diagnostic method proposed here, using, for the first time, recombinant antibody fragments, raises the possibility of developing a more affordable test to be used in the routine detection and surveillance of STEC infections.


Subject(s)
Escherichia coli Infections/diagnosis , Latex Fixation Tests , Shiga Toxin 1/isolation & purification , Shiga Toxin 2/isolation & purification , Shiga-Toxigenic Escherichia coli , Single-Chain Antibodies/immunology , Animals , Chlorocebus aethiops , Recombinant Proteins/immunology , Shiga-Toxigenic Escherichia coli/isolation & purification , Vero Cells
8.
IEEE J Transl Eng Health Med ; 8: 1900208, 2020.
Article in English | MEDLINE | ID: mdl-32219042

ABSTRACT

Objective: This work aims at providing novel endovascular instrumentation to overcome current technical limitations of in situ endograft fenestration including challenges in targeting the fenestration site under fluoroscopic control and supplying mechanical support during endograft perforation. Technology: Novel electromagnetically trackable instruments were developed to facilitate the navigation of the fenestration device and its stabilization at the target site. In vitro trials were performed to preliminary evaluate the proposed instrumentation for the antegrade in situ fenestration of an aortic endograft, using a laser guidewire designed ad hoc and the sharp end of a commercial endovascular guidewire. Results: In situ fenestration was successfully performed in 22 trials. A total of two laser tools were employed since an over bending of laser guidewire tip, due to its manufacturing, caused the damage of the sensor in the first device used. Conclusions: Preliminary in vitro trials demonstrate the feasibility of the proposed instrumentation which could widespread the procedure for in situ fenestration. The results obtained should be validated performing animal studies. Clinical Impact: The proposed instrumentation has the potential to expand indications for standard endovascular aneurysm repair to cases of acute syndromes.

9.
Nanotechnology ; 29(36): 365701, 2018 Sep 07.
Article in English | MEDLINE | ID: mdl-29894981

ABSTRACT

Magnetic nanoparticles (NPs) have attracted great attention owing to their applications in the biomedical field. In the present work, maghemite (γFe2O3) NPs of 6.5 nm were prepared using a sonochemical method and used to prepare magnetic beads through silanization with 3-aminopropyltrimethoxysilane (APTS). Subsequently, amino groups in the resulting APTS-γFe2O3 beads were converted to carboxylic acid (CARB-γFe2O3) through the succinic anhydride reaction, as confirmed by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and dynamic light scattering (DLS) measurements. The size of these beads was measured as 12 nm and their hydrodynamic diameter as 490 nm, using TEM analysis and DLS, respectively. The CARB-γFe2O3 beads were further functionalized by immobilizing rabbit antibodies on their surfaces; the immobilization was confirmed by flow cytometry and ionic strength. The samples were further characterized by Mössbauer spectroscopy and DC magnetization measurements. Studies on magnetic relaxivities showed that magnetic beads present great potential for application in MR imaging.


Subject(s)
Antibodies/metabolism , Ferric Compounds/chemical synthesis , Microspheres , Animals , Carboxylic Acids/chemistry , Dynamic Light Scattering , Ferric Compounds/chemistry , Fluorescence , Magnetic Resonance Imaging , Magnetics , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Particle Size , Propylamines/chemistry , Rabbits , Silanes/chemistry , Spectroscopy, Fourier Transform Infrared , Spectroscopy, Mossbauer , Static Electricity , Vibration , X-Ray Diffraction
12.
Epidemiol Infect ; 145(11): 2204-2211, 2017 08.
Article in English | MEDLINE | ID: mdl-28587697

ABSTRACT

Shiga toxin-producing Escherichia coli (STEC) is a known food pathogen, which main reservoir is the intestine of ruminants. The abundance of different STEC lineages in nature reflect a heterogeneity that is characterised by the differential expression of certain genotypic characteristics, which in turn are influenced by the environmental conditions to which the microorganism is exposed. Bacterial homeostasis and stress response are under the control of the alarmone guanosine tetraphosphate (ppGpp), which intrinsic levels varies across the E. coli species. In the present study, 50 STEC isolates from healthy sheep were evaluated regarding their ppGpp content, cytotoxicity and other relevant genetic and phenotypic characteristics. We found that the level of ppGpp and cytotoxicity varied considerably among the examined strains. Isolates that harboured the stx2 gene were the least cytotoxic and presented the highest levels of ppGpp. All stx2 isolates belonged to phylogroup A, while strains that carried stx1 or both stx1 and stx2 genes pertained to phylogroup B1. All but two stx2 isolates belonged to the stx2b subtype. Strains that belonged to phylogroup B1 displayed on average low levels of ppGpp and high cytotoxicity. Overall, there was a negative correlation between cytotoxicity and ppGpp.


Subject(s)
Guanosine Pentaphosphate/metabolism , Guanosine Tetraphosphate/metabolism , Sheep Diseases/microbiology , Sheep/microbiology , Shiga-Toxigenic Escherichia coli/genetics , Virulence Factors/genetics , Animals , Disease Reservoirs , Escherichia coli Infections/microbiology , Genetic Variation , Sheep Diseases/epidemiology , Shiga Toxin 2/metabolism , Shiga-Toxigenic Escherichia coli/immunology , Shiga-Toxigenic Escherichia coli/isolation & purification
13.
Ecotoxicol Environ Saf ; 144: 258-267, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28633104

ABSTRACT

Acetaminophen (paracetamol) (PAR) is one of the most popular non-steroidal anti-inflammatory drugs (NSAIDs) with analgesic and antipyretic properties consumed worldwide and often detected in the aquatic environment. Due to the fact that PAR induces oxidative stress in mammals, the aim of this study was to evaluate if similar effects were observed in oysters Crassostrea gigas, given their economic and ecological importance and worldwide distribution. Oysters were exposed for 1, 4 and 7 days to two different sublethal PAR concentrations (0, 1 and 100µgL-1). Cell viability, DNA damage in hemocytes and enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and glutathione S-transferases (GST) were evaluated in oyster gills. In addition, changes at transcriptional level of Cu/Zn superoxide dismutase (SOD), catalase-like (CAT-like), cytochrome P450 genes (CYP30C1, CYP2AU2, CYP3071A1, CYP356A1), glutathione S-transferase isoforms (GST-ω and GST-π-like), cyclooxygenase (COX), fatty acid binding proteins-like (FABP-like), and caspase genes were evaluated in oyster gills and digestive gland. No changes in cell viability and DNA damage were observed in oysters exposed to both PAR concentrations. Similarly, no significant changes were detected in the major antioxidant enzymes (except for auxiliary enzyme GR) in oyster gills, suggesting that changes in GR activity are enough to counteract a potential oxidative stress in C. gigas gills under these experimental conditions. Furthermore, changes at transcriptional level are concentration and tissue dependent. PAR elicited an inhibition of CYP30C1, CYP3071A1 and FABP-like transcripts highlighting their role in drug metabolism, transport and detoxification of PAR in the gills. GST transcript levels were type, tissue and concentration-dependent. GST-π-like was down-regulated in oyster gills exposed to the lowest PAR concentration and up-regulated in the digestive gland of oysters exposed to the highest PAR concentration. However, GST-ω transcript levels were lower only in oysters digestive gland exposed to the lowest PAR concentration. Therefore, changes at transcriptional level were more sensitive to assess the exposure to PAR at environmental relevant concentrations.


Subject(s)
Acetaminophen/toxicity , Antioxidants/metabolism , Crassostrea/drug effects , DNA Damage , Transcriptome/drug effects , Water Pollutants, Chemical/toxicity , Animals , Cell Survival/drug effects , Crassostrea/genetics , Dose-Response Relationship, Drug , Gills/drug effects , Gills/enzymology , Hemocytes/drug effects , Hemocytes/enzymology , Hemocytes/pathology , Oxidative Stress/drug effects , Oxidative Stress/genetics
14.
Sci Total Environ ; 590-591: 799-808, 2017 Jul 15.
Article in English | MEDLINE | ID: mdl-28291610

ABSTRACT

The 1999 Mw 7.4 earthquake triggered a tremendous human tragedy and had a great social impact over the population of the Izmit Bay, one of the most industrialized area of Turkey. Although the successive environmental disasters were well documented, information on its sedimentary record is lacking. The present research aims at filling this gap, through the analysis of organic contaminants (PCBs, PAHs, and PBDEs) in a dated sediment core collected in the depocenter of the Karamürsel Basin in 2005. Profiles of total PCBs and total PAHs overlap the timing of industrialization in the area (starting in the 1960s) with values increasing as the population and the number of industrial plants grew larger. Profiles for PBDEs are in accordance with increasing urban inputs but are probably affected by processes of natural formation and post-depositional mixing. The continuous sedimentary record is interrupted at a level dating back to 1980 due to the erosion caused by the 1999 earthquake, having removed a 5-7cm thick sediment layer. Contaminant concentrations in the deepest 10-15cm of a 30cm thick seismo-turbidite unit, triggered by the 1999 event, increase with the progressive fining up and evidence massive transport of sediments from coastal, more polluted sites of the north-eastern Karamürsel shelves and shores. Additional inputs of PAHs are also evident, originating from a fire at the oil refinery that followed the shaking. The effects of the earthquake generated tsunami, its backwash fluxes and the following seiches are not uniquely displayed by each class of contaminants, and they could probably reflect successive inputs deriving from different parts of the basin that are subject to anthropogenic impacts of different nature. Concentrations measured at the top of the core are consistent with an unvaried input of pollutants in the period 1980-2005.

15.
Vet Microbiol ; 184: 27-30, 2016 Feb 29.
Article in English | MEDLINE | ID: mdl-26854341

ABSTRACT

Psittacidae are frequently bred as pets worldwide, but little is known about the zoonotic risks of these animals. The objective of this study was to investigate the presence of Shiga toxin-producing Escherichia coli (STEC) in the feces of psittacine birds housed as pets. A total of 171 fecal samples (67 cockatiels, 59 budgerigars, and 45 agapornis) were cultured. Forty-two (E. coli) strains were identified, and the presence of the eae, stx1, and stx2 genes was determined using PCR. The antimicrobial resistance profiles of the STEC strains were determined using the disk diffusion method and phylogenetic analysis according to the new Clermont phylotyping method. Using these methods, 19.4% (8/42) of the STEC strains were determined to be positive for the eae and stx2 genes. The results revealed a STEC frequency of 4.6% in the birds (8/171), with a percentage of 8.47% in budgerigars (5/59), 4.47% in cockatiels (3/67), and 0% in agapornis (0/45). None of the STEC isolates belonged to the O157 serogroup. Most of the strains were classified as sensitive to the 18 antibiotics tested. None of the strains exhibited a multiresistance profile. In the phylogenetic analysis, two strains were classified as non-typeable, three were classified as B2, two were classified as F, and one was classified as Clade I. Seven of the eight STEC strains showed a clonal profile using AFLP. E. coli strains that are stx2(+) plus eae(+) are usually associated with severe human diseases such as hemorrhagic colitis and hemolytic-uremic syndrome. The STEC-positive results indicate the zoonotic risk of breeding psittacidae in home environments.


Subject(s)
Escherichia coli Infections/epidemiology , Parrots/microbiology , Pets/microbiology , Shiga-Toxigenic Escherichia coli/classification , Shiga-Toxigenic Escherichia coli/genetics , Zoonoses/epidemiology , Animals , Anti-Bacterial Agents/pharmacology , Escherichia coli Infections/microbiology , Escherichia coli Proteins/genetics , Feces/microbiology , Phylogeny , Prevalence , Risk Factors , Shiga-Toxigenic Escherichia coli/drug effects
16.
Environ Monit Assess ; 187(7): 480, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26130246

ABSTRACT

Dating of sediment cores in dynamic environments (such as tropical coastal lagoons) is often impossible to achieve, due to the difficulty to recover continuous and undisturbed records. Detailed temporal definition of environmental changes cannot be assured, but there is the possibility that information retained in such sediments can still provide useful insights on local or large-scale sedimentary dynamics, when a specific strategy is adopted. This latter consists in repeated core samplings at the same location and in the comparison of core profiles for basic and easily measurable parameters (porosity and sand content). This approach was tested on sediment cores, collected repeatedly during the period 2005-2010, at the same site of the Thi Nai Lagoon (central Vietnam). The proposed procedure was able to evidence the impact on lagoon sediments of activities linked to the construction of industrial settlements in the area, with dredging removing a consistent sediment layer from 2005 to 2008 and waste dumping providing additional sediment input in the following period. Simple statistic confirmed this scenario, together with core profiles of PCBs, As, Cd, Pb, and Zn. The procedure represents a simple tool to study coastal dynamics in places where the level of accuracy of traditional sediment radiodating cannot be reached. Several ameliorations are suggested in order to help developing the monitoring of sedimentary processes in poorly studied areas.


Subject(s)
Geologic Sediments/analysis , Environmental Monitoring/methods , Metals, Heavy/analysis , Polychlorinated Biphenyls/analysis , Porosity , Silicon Dioxide/analysis , Vietnam
17.
Mol Cancer Res ; 13(4): 775-83, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25421750

ABSTRACT

UNLABELLED: ALK is a tyrosine kinase receptor involved in a broad range of solid and hematologic tumors. Among 70% to 80% of ALK(+) anaplastic large cell lymphomas (ALCL) are caused by the aberrant oncogenic fusion protein NPM-ALK. Crizotinib was the first clinically relevant ALK inhibitor, now approved for the treatment of late-stage and metastatic cases of lung cancer. However, patients frequently develop drug resistance to Crizotinib, mainly due to the appearance of point mutations located in the ALK kinase domain. Fortunately, other inhibitors are available and in clinical trial, suggesting the potential for second-line therapies to overcome Crizotinib resistance. This study focuses on the ongoing phase I/II trial small-molecule tyrosine kinase inhibitor (TKI) AP26113, by Ariad Pharmaceuticals, which targets both ALK and EGFR. Two NPM-ALK(+) human cell lines, KARPAS-299 and SUP-M2, were grown in the presence of increasing concentrations of AP26113, and eight lines were selected that demonstrated resistance. All lines show IC50 values higher (130 to 1,000-fold) than the parental line. Mechanistically, KARPAS-299 populations resistant to AP26113 show NPM-ALK overexpression, whereas SUP-M2-resistant cells harbor several point mutations spanning the entire ALK kinase domain. In particular, amino acid substitutions: L1196M, S1206C, the double F1174V+L1198F and L1122V+L1196M mutations were identified. The knowledge of the possible appearance of new clinically relevant mechanisms of drug resistance is a useful tool for the management of new TKI-resistant cases. IMPLICATIONS: This work defines reliable ALCL model systems of AP26113 resistance and provides a valuable tool in the management of all cases of relapse upon NPM-ALK-targeted therapy.


Subject(s)
Drug Resistance, Neoplasm , Lymphoma, Large-Cell, Anaplastic/genetics , Organophosphorus Compounds/pharmacology , Point Mutation , Protein-Tyrosine Kinases/genetics , Pyrimidines/pharmacology , Receptor Protein-Tyrosine Kinases/genetics , Amino Acid Substitution , Anaplastic Lymphoma Kinase , Cell Line, Tumor , Exome , Humans , Inhibitory Concentration 50 , Lymphoma, Large-Cell, Anaplastic/drug therapy , Receptor Protein-Tyrosine Kinases/chemistry , Receptor Protein-Tyrosine Kinases/metabolism , Sequence Analysis, DNA , Up-Regulation
18.
J Phys Condens Matter ; 26(46): 464106, 2014 Nov 19.
Article in English | MEDLINE | ID: mdl-25347466

ABSTRACT

Pectin is a natural biopolymer that forms, in the presence of divalent cations, ionic-bound gels typifying a large class of biological gels stabilized by non-covalent cross-links. We investigate and compare the kinetics of formation and aging of pectin gels obtained either through external gelation via perfusion of free Ca(2+) ions, or by internal gelation due to the supply of the same ions from the dissolution of CaCO3 nanoparticles. The microscopic dynamics obtained with photon correlation imaging, a novel optical technique that allows obtaining the microscopic dynamics of the sample while retaining the spatial resolution of imaging techniques, is contrasted with macroscopic rheological measurements at constant strain. Pectin gelation is found to display peculiar two-stage kinetics, highlighted by non-monotonic growth in time of both microscopic correlations and gel mechanical strength. These results are compared to those found for alginate, another biopolymer extensively used in food formulation.


Subject(s)
Alginates/chemistry , Calcium/chemistry , Gels , Pectins/chemistry , Rheology , Computer Simulation , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Kinetics , Microscopy, Electron , Molecular Structure , Thermodynamics
19.
Anal Bioanal Chem ; 405(28): 9113-23, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24057024

ABSTRACT

Domoic acid (DA) is a neurotoxin produced by different algae, including pennate diatoms, principally from the genus Pseudo-nitzschia, and it is the main cause of amnesic shellfish poisoning. Determination of this toxin in seawater samples is fundamental to define the real contamination risks for aquatic species. We have developed two very sensitive instrumental methods using hydrophilic interaction liquid chromatography coupled using tandem mass spectrometry in positive and negative polarity modes. Instrumental detection limits were 9 pg mL(-1) for positive and 19 pg mL(-1) for negative ionisation. A procedural method based on solid-phase extraction for the determination of dissolved DA present in seawater has been developed, and an extraction procedure was employed for the determination of the toxin in the particulate fraction. DA quantification was performed using the internal standard method to account for signals fluctuations and random errors during sample treatment. To our knowledge, this is the first study to use this quantification method for DA determination. Trueness, extraction yield, matrix effects, repeatability and procedural detection limits were evaluated during method validation. Procedural detection limits of 0.3 pg mL(-1) (positive mode) and 0.6 pg mL(-1) (negative mode) were found for the dissolved fraction, and absolute limits of 0.4 pg (positive mode) and 6.0 pg (negative mode) for particulate samples were obtained. The most sensitive method in positive mode was applied to define DA occurrence in the Venice Lagoon. Trace concentrations of domoic acid ranging from 1.5 to 16.2 pg mL(-1) were found for the first time in the Venetian environment.


Subject(s)
Chromatography, High Pressure Liquid/methods , Kainic Acid/analogs & derivatives , Marine Toxins/analysis , Seawater/analysis , Tandem Mass Spectrometry/methods , Chromatography, High Pressure Liquid/standards , Kainic Acid/analysis , Reference Standards , Tandem Mass Spectrometry/standards
20.
Anal Bioanal Chem ; 405(2-3): 917-32, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23073699

ABSTRACT

The development of a unique analytical method for the determination of five classes of persistent organic pollutants (POPs) in atmospheric gas and the particle phase through gas chromatography coupled to high-resolution mass spectrometry is presented. Every step of the pre-analytical and analytical optimization process is described. Great effort was put into simplifying the traditional techniques, with reference to EPA and literature methods. Automated instruments were used for sample extraction and cleanup in order to enhance repeatability and reduce contamination risks. Unlike most common approaches, no separation of the analytes was performed before the GC analysis in order to avoid sample fractionation and to save time and materials. This allowed low instrumental and method detection limits (pg to sub-pg) to be achieved. Accuracy and precision were tested by fortifying the matrix and analysing standard reference materials (NIST SRM 1649b Urban Dust and 2585 Organic Contaminants in House Dust). The method was applied to five samples from Terra Nova Bay, Antarctica. Concentrations of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) are presented. Lighter compounds dominate the distribution and are mainly present in the gaseous phase. The observed pattern may be attributable to long-range transport. Results are in general agreement with literature data, where available.


Subject(s)
Air Pollutants/analysis , Benzofurans/analysis , Chromatography, Gas/methods , Halogenated Diphenyl Ethers/analysis , Polychlorinated Biphenyls/analysis , Polychlorinated Dibenzodioxins/analogs & derivatives , Polycyclic Aromatic Hydrocarbons/analysis , Polymers/analysis , Antarctic Regions , Polychlorinated Dibenzodioxins/analysis
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