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1.
Ann Hematol ; 103(6): 1931-1940, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38478023

ABSTRACT

Ruxolitinib is beneficial in patients with myelofibrosis (MF) and polycythemia vera (PV). Information on ruxolitinib adherence is scant. The Ruxolitinib Adherence in Myelofibrosis and Polycythemia Vera (RAMP) prospective multicenter study (NCT06078319) included 189 ruxolitinib-treated patients. Patients completed the Adherence to Refills and Medications Scale (ARMS) and Distress Thermometer and Problem List (DTPL) at the earliest convenience, after registration in the study, and at later timepoints. At week-0, low adherence (ARMS > 14) and high distress (DT ≥ 4) were declared by 49.7% and 40.2% of patients, respectively. The main reason for low adherence was difficult ruxolitinib supply (49%), intentional (4.3%) and unintentional (46.7%) non-take. In multivariable regression analysis, low adherence was associated to male sex (p = 0.001), high distress (p < 0.001), and treatment duration ≥ 1 year (p = 0.03). Over time, rates of low adherence and high distress remained stable, but unintentional non-take decreased from 47.9% to 26.0% at week-48. MF patients with stable high adherence/low distress were more likely to obtain/maintain the spleen response at week-24. Low adherence to ruxolitinib represents an unmet clinical need that require a multifaceted approach, based on reason behind it (patients characteristics and treatment duration). Its recognition may help distinguishing patients who are truly refractory and those in need of therapy optimization.


Subject(s)
Medication Adherence , Nitriles , Polycythemia Vera , Primary Myelofibrosis , Pyrazoles , Pyrimidines , Humans , Primary Myelofibrosis/drug therapy , Pyrimidines/therapeutic use , Pyrazoles/therapeutic use , Male , Polycythemia Vera/drug therapy , Female , Prospective Studies , Aged , Middle Aged , Italy/epidemiology , Medication Adherence/statistics & numerical data , Aged, 80 and over , Adult
2.
Front Pharmacol ; 14: 1154377, 2023.
Article in English | MEDLINE | ID: mdl-37033642

ABSTRACT

TKIs long-term treatment in CML may lead to persistent adverse events (AEs) that can promote relevant morbidity and mortality. Consequently, TKIs dose reduction is often used to prevent AEs. However, data on its impact on successful treatment-free remission (TFR) are quite scarce. We conducted a retrospective study on the outcome of CML subjects who discontinued low-dose TKIs from 54 Italian hematology centers participating in the Campus CML network. Overall, 1.785 of 5.108 (35.0%) regularly followed CML patients were treated with low-dose TKIs, more frequently due to relevant comorbidities or AEs (1.288, 72.2%). TFR was attempted in 248 (13.9%) subjects, all but three while in deep molecular response (DMR). After a median follow-up of 24.9 months, 172 (69.4%) patients were still in TFR. TFR outcome was not influenced by gender, Sokal/ELTS risk scores, prior interferon, number and last type of TKI used prior to treatment cessation, DMR degree, reason for dose reduction or median TKIs duration. Conversely, TFR probability was significantly better in the absence of resistance to any prior TKI. In addition, patients with a longer DMR duration before TKI discontinuation (i.e., >6.8 years) and those with an e14a2 BCR::ABL1 transcript type showed a trend towards prolonged TFR. It should also be emphasized that only 30.6% of our cases suffered from molecular relapse, less than reported during full-dose TKI treatment. The use of low-dose TKIs does not appear to affect the likelihood of achieving a DMR and thus trying a treatment withdrawal, but might even promote the TFR rate.

3.
Carbohydr Polym ; 283: 119145, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35153024

ABSTRACT

Polysaccharide-based hydrogels are achieving remarkable performances in chronic wounds treatment. In this work, a carboxymethyl cellulose-based hydrogel film was developed to support skin repair. The hydrogel was loaded with berberine, a polyphenolic molecule endowing antioxidant and cytoprotective features. The film was physico-chemically characterized and in vitro tested on keratinocytes and fibroblasts subjected to oxidative stress. The biocomposite showed high thermal stability (onset decomposition temperature 245 °C) and significant fluid uptake performances, both in free conditions (up to 6510%) and under external pressure (up to 3400%). Moreover, it was able to control oxidative stress and inflammation markers involved in wound chronicity. Keratinocytes hyperproliferation, features that normally hamper injury restoration, was reduced of 25%. Our results showed that the combination of berberine and hydrogel provides a synergic improvement of the material properties. The biocomposite represents a promising candidate for dermatological applications against oxidative stress at the chronic wound site, promoting the healing process.


Subject(s)
Berberine/pharmacology , Carboxymethylcellulose Sodium/chemistry , Hydrogels/pharmacology , Wound Healing/drug effects , Antioxidants/pharmacology , Bandages , Berberine/chemistry , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Cell Survival/drug effects , Fibroblasts/drug effects , Humans , Hydrogels/chemistry , Keratinocytes/drug effects , Oxidative Stress/drug effects , Spectroscopy, Fourier Transform Infrared/methods , Temperature
4.
Food Chem ; 336: 127590, 2021 Jan 30.
Article in English | MEDLINE | ID: mdl-32763742

ABSTRACT

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.


Subject(s)
Food Quality , Food Storage/methods , Oils, Volatile/pharmacology , Penicillium/drug effects , Thymus Plant/metabolism , Antioxidants/chemistry , Citrus/chemistry , Citrus/metabolism , Citrus/microbiology , Cold Temperature , Fruit and Vegetable Juices/analysis , Gas Chromatography-Mass Spectrometry , Hydrogen-Ion Concentration , Oils, Volatile/analysis , Penicillium/physiology
5.
Rev Neurol ; 70(4): 134-138, 2020 Feb 16.
Article in Spanish | MEDLINE | ID: mdl-32043535

ABSTRACT

INTRODUCTION: Panayiotopoulos syndrome (PS) is a common form of epilepsy in childhood that is classified as one of the benign idiopathic focal epilepsies. There is no consensus on the indication of neuroimaging in the presence of an electroclinical picture consistent with this disorder. Two cases are presented that began with an electroclinical pattern compatible with PS and in which alterations in the occipital structure were finally detected. CASE REPORTS: Two girls aged 5 and 6 years who began with episodes consistent with PS. In both cases neuroimaging showed structural lesions (cortical dysplasia and pleomorphic xanthoastrocytoma), and hence the final diagnosis was occipital symptomatic focal epilepsy, with the ensuing change in the prognosis and treatment. CONCLUSIONS: The literature describes abnormalities in cranial magnetic resonance imaging in 10-20% of diagnosed cases of PS in which a scan is performed, although the diagnosis of PS is not always changed (matching lesions). Both cases exemplify the importance of reaching a correct diagnosis through a detailed study that must include neuroimaging, since, in some patients, causal brain injuries will be detected and as a result the diagnosis, treatment and evolution will be significantly different.


TITLE: Epilepsia sintomática con inicio que imita el síndrome de Panayiotopoulos: importancia de la neuroimagen.Introducción. El síndrome de Panayiotopoulos (SP) es una epilepsia frecuente en la infancia que se clasifica dentro de las epilepsias focales idiopáticas benignas. No existe consenso sobre la indicación de neuroimagen ante un cuadro electroclínico compatible con este trastorno. Se presentan dos casos que comenzaron con un patrón electroclínico compatible con SP y en los que finalmente se detectaron alteraciones estructurales occipitales. Casos clínicos. Dos niñas de 5 y 6 años que comenzaron con episodios compatibles electroclínicamente con SP. En ambos casos, la neuroimagen mostró lesiones estructurales (displasia cortical y xantoastrocitoma pleomórfico), por lo que finalmente el diagnóstico fue de epilepsia focal sintomática occipital, con el consiguiente cambio en el pronóstico y el tratamiento. Conclusiones. En la bibliografía se describen anomalías en la resonancia magnética craneal en un 10-20% de los casos diagnosticados de SP en los que se realiza una prueba de imagen, aunque no siempre se modifica el diagnóstico de SP (lesiones coincidentes). Ambos casos ejemplifican la importancia de alcanzar un diagnóstico correcto mediante un estudio detallado que ha de incluir la realización de neuroimagen, ya que, en algunos pacientes, se detectarán lesiones cerebrales causales, por lo que el diagnóstico, el tratamiento y la evolución serán drásticamente distintos.


Subject(s)
Epilepsies, Partial/diagnostic imaging , Magnetic Resonance Imaging , Neuroimaging , Child , Child, Preschool , Electroencephalography , Epilepsies, Partial/physiopathology , Female , Humans
6.
Calcif Tissue Int ; 100(1): 40-46, 2017 01.
Article in English | MEDLINE | ID: mdl-27743017

ABSTRACT

Systemic Mastocytosis has been long identified as a potential cause of osteoporosis; nevertheless, data regarding longitudinal variation of bone mineral density (BMD) in patients with indolent systemic mastocytosis (ISM) are missing . We studied BMD variation at lumbar spine and proximal hip after 30-month (±6 months) follow-up in a large cohort of patients (83) with ISM without osteoporosis, supplementated with vitamin D and/or calcium when needed. We also analyzed the correlation between variation of BMD, basal serum tryptase levels and bone turnover markers (BTM). Sixty-four percent of our population was male; mean age was 52.1 (±11.5) years. Vitamin D insufficiency (serum levels of 25-OH-vitamin D, 25OHD, lower than 75 nmol/L) was found in more than 70 % of patients. After a follow-up of 30 ± 6 months with only vitamin D (5000-7500 IU weekly of oral cholecalciferol) or calcium (500 mg/die) supplementation when needed, we observed 2.1 % increase in BMD at lumbar spine, with no significant changes at hip. At the end of follow-up, almost 60 % of patients showed 25OHD serum levels still lower than recommended, despite vitamin D supplementation. Reduction in BMD after follow-up significantly correlated with high C-telopeptide of type I collagen serum levels at the time of diagnosis. In patients with ISM without osteoporosis, a routinary BMD evaluation within a time <2 years is not justified, except in the presence of elevated BTM. In these patients, vitamin D supplementation is frequently needed.


Subject(s)
Bone Density/physiology , Bone and Bones/metabolism , Mastocytosis, Systemic/metabolism , Vitamin D/blood , Adult , Aged , Biomarkers/blood , Calcium/blood , Female , Humans , Longitudinal Studies , Male , Middle Aged , Osteoporosis/metabolism
7.
Data Brief ; 7: 1335-40, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27158646

ABSTRACT

This data article is related to our recently published research paper "Exploiting a new glycerol-based copolymer as a route to wound healing: synthesis, characterization and biocompatibility assessment", De Giglio et al. (Colloids and Surfaces B: Biointerfaces 136 (2015) 600-611) [1]. The latter described a new copolymer derived from glycerol and tartaric acid (PGT). Herein, an investigation about the PGT-ciprofloxacin (CIP) interactions by means of Fourier Transform Infrared Spectroscopy (FT-IR) acquired in Attenuated Total Reflectance (ATR) mode and Differential Scanning Calorimetry (DSC) was reported. Moreover, CIP release experiments on CIP-PGT patches were performed by High Performance Liquid Chromatography (HPLC) at different pH values.

8.
Colloids Surf B Biointerfaces ; 136: 600-11, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26461426

ABSTRACT

The use of biocompatible materials based on naturally derived monomers plays a key role in pharmaceutical and cosmetic industries. In this paper we describe the synthesis of a new low molecular weight copolymer, based on glycerol and l-tartaric acid, useful to develop biocompatible dermal patches with drug delivery properties. The copolymer's chemical composition was assessed by FT-IR (Fourier transform infrared spectroscopy), (1)H NMR ((1)H Nuclear Magnetic Resonance) and XPS (X-ray photoelectron spectroscopy), while its molecular weight distribution was estimated by SEC (size exclusion chromatography). Copolymer thermal properties were studied by TGA (thermogravimetric analysis). Biological evaluations by MTT assay and SEM (scanning electron microscopy) observations performed with murine fibroblasts and human keratinocytes (HaCaT) revealed a good compatibility of the proposed copolymer. Ciprofloxacin was selected as model drug and its release was evaluated by HPLC (high performance liquid chromatography), showing that the new copolymer supplied promising results as drug delivery system for wound healing applications. Furthermore, investigations on Skin-Mesenchymal stem cells (S-MSCs) behaviour and gene expression showed that the copolymer and its combination with ciprofloxacin did not affect their stemness. In this regard, the fabrication of dermal patches with new, low cost materials for local treatment of skin infections represents an attractive strategy in order to bypass the worrying side effects of systemic antibiotic therapy. Overall, the performed physico-chemical characterization, drug release test and biological evaluations showed that this new copolymer could be a promising tool for the in situ delivery of bioactive molecules during skin lesions treatment.


Subject(s)
Biocompatible Materials , Glycerol/chemistry , Polymers/chemistry , Wound Healing , Animals , Cell Line , Humans , Mice , Microscopy, Electron, Scanning , Proton Magnetic Resonance Spectroscopy
9.
Appl Biochem Biotechnol ; 175(8): 3840-55, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25712908

ABSTRACT

Catechol-O-methyltransferase (COMT, EC 2.1.1.6) is an enzyme that catalyzes the methylation of catechol substrates, and while structural and functional studies of its membrane-bound isoform (MBCOMT) are still hampered by low recombinant production, Pichia pastoris has been described as an attractive host for the production of correctly folded and inserted membrane proteins. Hence, in this work, MBCOMT biosynthesis was developed using P. pastoris X33 and KM71H cells in shake flasks containing a semidefined medium with different methanol concentrations. Moreover, after P. pastoris glass beads lysis, biologically and immunologically active hMBCOMT was found mainly in the solubilized membrane fraction whose kinetic parameters were identical to its correspondent native enzyme. In addition, mixed feeds of methanol and glycerol or sorbitol were also employed, and its levels quantified using liquid chromatography coupled to refractive index detection. Overall, for the first time, two P. pastoris strains with opposite phenotypes were applied for MBCOMT biosynthesis under the control of the strongly methanol-inducible alcohol oxidase (AOX) promoter. Moreover, this eukaryotic system seems to be a promising approach to deliver MBCOMT in high quantities from fermentor cultures with a lower cost-benefit due to the cheaper cultivation media coupled with the higher titers tipically achieved in biorreactors, when compared with previously reported mammallian cell cultures.


Subject(s)
Catechol O-Methyltransferase/biosynthesis , Membrane Proteins/biosynthesis , Pichia/enzymology , Recombinant Proteins/biosynthesis , Alcohol Oxidoreductases/metabolism , Catechol O-Methyltransferase/genetics , Cell Culture Techniques , Fermentation , Glycerol/chemistry , Membrane Proteins/metabolism , Methanol/metabolism , Phenotype , Pichia/genetics , Recombinant Proteins/genetics
10.
Br J Pharmacol ; 172(7): 1739-52, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25409768

ABSTRACT

BACKGROUND AND PURPOSE: Catechol-O-methyltransferase (COMT) is an important target in the levodopa treatment of Parkinson's disease; however, the inhibitors available have problems, and not all patients benefit from their efficacy. Opicapone was developed to overcome those limitations. In this study, opicapone's pharmacological properties were evaluated as well as its potential cytotoxic effects. EXPERIMENTAL APPROACH: The pharmacodynamic effects of opicapone were explored by evaluating rat COMT activity and levodopa pharmacokinetics, in the periphery through microdialysis and in whole brain. The potential cytotoxicity risk of opicapone was explored in human hepatocytes by assessing cellular ATP content and mitochondrial membrane potential. KEY RESULTS: Opicapone inhibited rat peripheral COMT with ED50 values below 1.4 mg⋅kg(-1) up to 6 h post-administration. The effect was sustained over the first 8 h and by 24 h COMT had not returned to control values. A single administration of opicapone resulted in increased and sustained plasma levodopa levels with a concomitant reduction in 3-O-methyldopa from 2 h up to 24 h post-administration, while tolcapone produced significant effects only at 2 h post-administration. The effects of opicapone on brain catecholamines after levodopa administration were sustained up to 24 h post-administration. Opicapone was also the least potent compound in decreasing both the mitochondrial membrane potential and the ATP content in human primary hepatocytes after a 24 h incubation period. CONCLUSIONS AND IMPLICATIONS: Opicapone has a prolonged inhibitory effect on peripheral COMT, which extends the bioavailability of levodopa, without inducing toxicity. Thus, it exhibits some improved properties compared to the currently available COMT inhibitors.


Subject(s)
Catechol O-Methyltransferase Inhibitors/pharmacology , Levodopa/pharmacokinetics , Oxadiazoles/pharmacology , Adenosine Triphosphate/metabolism , Animals , Antiparkinson Agents/pharmacology , Benzophenones/pharmacology , Brain/drug effects , Brain/metabolism , Catechol O-Methyltransferase/metabolism , Catechols/pharmacology , Cell Survival/drug effects , Cells, Cultured , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Levodopa/blood , Male , Membrane Potential, Mitochondrial/drug effects , Models, Biological , Nitriles/pharmacology , Nitrophenols/pharmacology , Oxadiazoles/blood , Oxadiazoles/pharmacokinetics , Rats, Wistar , Tolcapone
11.
Ann Oncol ; 26(1): 185-192, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25361995

ABSTRACT

BACKGROUND: The incidence of chronic myeloid leukemia (CML) increases with age, but it is unclear how the characteristics of the disease vary with age. In children, where CML is very rare, it presents with more aggressive features, including huge splenomegaly, higher cell count and higher blast cell percentage. PATIENTS AND METHODS: To investigate if after childhood the disease maintains or loses these characteristics of aggressiveness, we analyzed 2784 adult patients, at least 18 years old, registered by GIMEMA CML WP over a 40-year period. RESULTS: Young adults (YAs: 18-29 years old) significantly differed from adults (30-59 years old) and elderly patients (at least 60 years old) particularly for the frequency of splenomegaly (71%, 63% and 55%, P < 0.001), and the greater spleen size (median value: 4.5, 3.0 and 1.0 cm, P < 0.001). According to the EUTOS score, that is age-independent, high-risk patients were more frequent among YAs, than among adult and elderly patients (18%, 9% and 6%, P < 0.001). In tyrosine kinase inhibitors-treated patients, the rates of complete cytogenetic and major molecular response were lower in YAs, and the probability of transformation was higher (16%, 5% and 7%, P = 0.011). CONCLUSIONS: The characteristics of CML or the host response to leukemia differ with age. The knowledge of these differences and of their causes may help to refine the treatment and to improve the outcome. CLINICAL TRIAL NUMBERS: NCT00510926, NCT00514488, NCT00769327, NCT00481052.


Subject(s)
Antineoplastic Agents/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein Kinase Inhibitors/therapeutic use , Splenomegaly/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Protein-Tyrosine Kinases/antagonists & inhibitors , Spleen/pathology , Young Adult
12.
Neuropharmacology ; 77: 334-41, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24148813

ABSTRACT

OBJECTIVE: The present study aimed at evaluating the effect of opicapone, a third generation nitrocatechol catechol-O-methyltransferase (COMT) inhibitor, on the systemic and central bioavailability of 3,4-dihydroxy-l-phenylalanine (levodopa) and related metabolites in the cynomolgus monkey. METHODS: Four monkeys, implanted with guiding cannulas for microdialysis probes, in the substantia nigra, dorsal striatum and prefrontal cortex, were randomized in two groups that received, in a crossover design, vehicle or 100 mg/kg opicapone for 14 days. Twenty-three hours after last administration of vehicle or opicapone, animals were challenged with levodopa/benserazide (12/3 mg/kg). Extracellular dialysate and blood samples were collected over 360 min (at 30 min intervals) for the assays of catecholamine and COMT activity. RESULTS: Opicapone increased levodopa systemic exposure by 2-fold not changing Cmax values and reduced both 3-O-methyldopa (3-OMD) exposure and Cmax values by 5-fold. These changes were accompanied by ∼76-84% reduction in erythrocyte COMT activity. In dorsal striatum and substantia nigra, opicapone increased levodopa exposure by 1.7- and 1.4-fold, respectively, reducing 3-OMD exposure by 5- and 7-fold respectively. DOPAC exposure was increased by 4-fold in the substantia nigra. In the prefrontal cortex, opicapone increased levodopa exposure and reduced 3-OMD levels by 2.3- and 2.4-fold, respectively. CONCLUSIONS: Opicapone behaved as long-acting COMT inhibitor that markedly increased systemic and central levodopa bioavailability. Opicapone is a strong candidate to fill the unmet need for COMT inhibitors that lead to more sustained levodopa levels in Parkinson's disease patients.


Subject(s)
Antiparkinson Agents/pharmacology , Brain/drug effects , Catechol O-Methyltransferase Inhibitors , Dopamine Agents/pharmacokinetics , Levodopa/pharmacokinetics , Oxadiazoles/pharmacology , Animals , Antiparkinson Agents/pharmacokinetics , Brain/metabolism , Cross-Over Studies , Drug Interactions , Female , Macaca fascicularis , Male , Parkinson Disease/drug therapy
13.
Biotechnol Rep (Amst) ; 3: 34-41, 2014 Sep.
Article in English | MEDLINE | ID: mdl-28626646

ABSTRACT

Catechol-O-methyltransferase (COMT, EC 2.1.1.6) plays a crucial role in dopamine metabolism which has intimately linked this enzyme to some neurodegenerative diseases, such as Parkinson's disease. In recent years, in the attempt of developing new therapeutic strategies for Parkinson's disease, there has been a growing interest in the search for effective COMT inhibitors. In order to do so, large amounts of COMT in an active form are needed, and the best way to achieve this is by up-scaling its production through biotechnological processes. In this work, a fed-batch process for the biosynthesis of the soluble isoform of COMT in Escherichia coli is proposed. This final process was selected through the evaluation of the effect of different dissolved oxygen concentrations, carbon and nitrogen source concentrations and feeding profiles on enzymatic production and cell viability, while controlling various parameters (pH, temperature, starting time of the feeding and induction phases and carbon source concentration) during the process. After several batch and fed-batch experiments, a final specific COMT activity of 442.34 nmol/h/mg with approximately 80% of viable cells at the end of the fermentation were achieved. Overall, the results described herein provide a great improvement on hSCOMT production in recombinant bacteria and provide a new and viable option for the use of a fed-batch fermentation with a constant feeding profile to the large scale production of this enzyme.

14.
J Sep Sci ; 37(1-2): 20-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24285473

ABSTRACT

The development of new catechol-O-methyltransferase inhibitors has led to an improvement in the treatment of Parkinson's disease. However, despite the fact that the soluble isoform has been extensively investigated, few studies have been published concerning membrane isoform chromatographic recovery and bioactivity levels. In this work, chromatographic profiles of both catechol-O-methyltransferase isoforms were compared using quaternary amine as a ligand to evaluate its activity levels and recovery rates. Results show that both proteins required different conditions for adsorption; the soluble isoform adsorption was performed at low ionic strength, while the membrane isoform required increasing linear salt gradient. However, the application of 0.5% Triton X-100 promoted membrane isoform adsorption even at low ionic strength. Indeed, chromatographic conditions of both isoforms became similar when detergents were applied. The developed methods also appear to be highly effective in bioactivity recovery, presenting rates of 107% for soluble protein and 67 and 91% for membrane isoform without and with detergents, respectively. The chromatographic strategies with and without detergents resulted in a 4.3- and sevenfold purification, respectively, corresponding to specific activity values of 331 and 496 nmol/h/mg. Thus, the use of Q-sepharose as anion exchanger was effective in the recovery of both enzymes, which is a requirement for further kinetic and pharmacological trials.


Subject(s)
Catechol O-Methyltransferase/isolation & purification , Chromatography, Ion Exchange/methods , Sepharose/chemistry , Adsorption , Anion Exchange Resins/chemistry , Catechol O-Methyltransferase/chemistry , Chromatography, Ion Exchange/instrumentation , Humans , Isoenzymes/chemistry , Isoenzymes/isolation & purification , Kinetics
15.
J Biotechnol ; 160(3-4): 161-8, 2012 Aug 31.
Article in English | MEDLINE | ID: mdl-22498435

ABSTRACT

The aim of this work was to optimize the temperature, pH and stirring rate of the production of human soluble catechol-O-methyltransferase (hSCOMT) in a batch Escherichia coli culture process. A central composite design (CCD) was firstly employed to design the experimental assays used in the evaluation of these operational parameters on the hSCOMT activity for a semi-defined and complex medium. Predictive artificial neural network (ANN) models of the hSCOMT activity as function of the combined effects of these variables was proposed based on this exploratory experiments performed for the two culture media. The regression coefficients (R(2)) for the final models were 0.980 and 0.983 for the semi-defined and complex medium, respectively. The ANN models predicted a maximum hSCOMT activity of 183.73 nmol/h, at 40 °C, pH 6.5 and stirring rate of 351 rpm, and 132.90 nmol/h, at 35 °C, pH 6.2 and stirring rate of 351 rpm, for semi-defined and complex medium, respectively. These results represent a 4-fold increase in total hSCOMT activity by comparison to the standard operational conditions used for this bioprocess at slight scale.


Subject(s)
Algorithms , Bioreactors/microbiology , Catechol O-Methyltransferase/biosynthesis , Cell Culture Techniques/methods , Escherichia coli/physiology , Neural Networks, Computer , Biofeedback, Psychology/physiology , Catechol O-Methyltransferase/chemistry , Catechol O-Methyltransferase/genetics , Humans , Protein Engineering/methods , Solubility
16.
J Biotechnol ; 156(2): 141-6, 2011 Nov 10.
Article in English | MEDLINE | ID: mdl-21889552

ABSTRACT

Membrane proteins constitute 20-30% of all proteins encoded by the genome of various organisms. While large amounts of purified proteins are required for pharmaceutical and crystallization attempts, there is an unmet need for the development of novel heterologous membrane protein overexpression systems. Specifically, we tested the application of Brevibacillus choshinensis cells for the biosynthesis of human membrane bound catechol-O-methyltransferase (hMBCOMT). In terms of the upstream stage moderate to high expression was obtained for complex media formulation with a value near 45 nmol/h/mg for hMBCOMT specific activity achieved at 20 h culture with 37°C and 250 rpm. Subsequently, the efficiency for reconstitution of hMBCOMT is markedly null in the presence of ionic detergents, such as sodium dodecyl sulphate (SDS). In general, for non-ionic and zwiterionic detergents, until a detergent critic micellar concentration (CMC) of 1.0 mM, hMBCOMT shows more biological activity at lower detergent concentrations while for detergent CMC higher than 1 mM, higher detergent concentrations seem to be ideal for hMBCOMT solubilization. Indeed, from the detergents tested, the non-ionic digitonin at 0.5% (w/v) appears to be the most suitable for hMBCOMT solubilization.


Subject(s)
Brevibacillus , Catechol O-Methyltransferase , Recombinant Proteins , Batch Cell Culture Techniques , Catechol O-Methyltransferase/genetics , Catechol O-Methyltransferase/isolation & purification , Catechol O-Methyltransferase/metabolism , Humans , Membrane Proteins/metabolism , Protein Binding , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification
17.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(19): 1704-6, 2011 Jun 01.
Article in English | MEDLINE | ID: mdl-21543270

ABSTRACT

In the last years, chromatographic supports with amino acids as immobilized ligands (AAILs) were been used successfully for isolation of several biomolecules, such as proteins. In this context and based on specific properties of human soluble cathecol-O-methyltransferase (hSCOMT), we screened and analyzed the effect of experimental conditions, such as pH and ionic strength manipulation for hSCOMT adsorption, over six different AAIL commercial supports. Typically, the proteins adsorption on AAIL chromatographic supports is around their pI. While hSCOMT isoelectric point is around 5.5, this parameter leads us to design new adsorption strategies with several acid buffers for the chromatographic process. In terms of the ionic strength manipulation strategy, the results suggest that the AAILs-hSCOMT interaction is strongly affected by the intrinsic hSCOMT hydrophobic domains. On the other hand, the interaction mechanism of hSCOMT on amino acid resins appears to be highly dependent on the binding pH. Consequently the retention mechanism of the target enzyme on the AAILs can be as either in typical hydrophobic or ionic chromatographic supports, so long as selecting various mobile phases and separation conditions. In spite of these mixed-mode interactions and operation strategies, the elution of interferent's proteins from recombinant host can be achieved only with suitable adjusts in pH mobile phase set point. This lead to a new approach in biochromatographic COMT retention, while possess a higher specificity than other chromatographic methods reported in literature.


Subject(s)
Catechol O-Methyltransferase/isolation & purification , Chromatography, Affinity/methods , Immobilized Proteins/metabolism , Adsorption , Amino Acids/chemistry , Amino Acids/metabolism , Catechol O-Methyltransferase/metabolism , Escherichia coli/chemistry , Escherichia coli/enzymology , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Immobilized Proteins/chemistry , Osmolar Concentration , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism
18.
Biomed Chromatogr ; 24(8): 858-62, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20024892

ABSTRACT

Sodium citrate (SC) and low temperatures between 7 and 5 degrees C are effective in suppressing aggregation of proteins and may be beneficial to be included during a purification process. In this work, we analyzed the application of dual salt system, ammonium sulfate (AS) and SC on binding and elution conditions of recombinant hSCOMT on typical HIC sorbents. Specifically in butyl and octyl supports, the use of, respectively, 300 mM AS/200 mM SC and 25 mM AS/25 mM SC in the loading buffer resulted in complete binding of COMT. Elution was obtained by decreasing the ionic strength to 0 M of salt. For the delineate goal, it also favorably increased the support chain length while a consequent decrease in the dual ionic strength was observed for hSCOMT retention. In the presence of dual salt systems octyl media exhibited classic HIC behavior, good protein selectivity, an excellent purification factor and reduced denaturation effects of hSCOMT observed with higher salt concentrations. Also the inclusion of temperature control during the elution step appears to be advantageous for greater activity recovery without enzyme aggregation. In fact, these results could allow the prediction of most stabilizing conditions for this termolabile enzyme on the chromatographic stage, regarding salt types and therefore effectiveness to improve HIC selectivity and desirable purity on the target fractions.


Subject(s)
Catechol O-Methyltransferase/isolation & purification , Chromatography, Liquid/methods , Ammonium Sulfate/chemistry , Catechol O-Methyltransferase/chemistry , Chromatography, Liquid/instrumentation , Citrates/chemistry , Cold Temperature , Humans , Hydrophobic and Hydrophilic Interactions , Osmolar Concentration , Protein Binding , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , Sodium Citrate
19.
J Microbiol Biotechnol ; 19(9): 972-81, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19809255

ABSTRACT

In this paper, a fed-batch cultivation process in recombinant Escherichia coli BL21(DE3) bacteria, for the production of human soluble catechol-O-methyltransferase (hSCOMT), is presented. For the first time, a straightforward model is applied in a recombinant hSCOMT expression system and distinguishes an initial cell growth phase from a protein production phase upon induction. Specifically, the kinetic model predicts biomass, substrate, and product concentrations in the culture over time and was identified from a series of fed-batch experiments designed by testing several feed profiles. The main advantage of this model is that its parameters can be identified more reliably from distinct fed-batch strategies, such as glycerol pulses and exponential followed by constant substrate additions. Interestingly, with the limited amount of data available, the proposed model accomplishes satisfactorily the experimental results obtained for the three state variables, and no exhaustive process knowledge is required. The comparison of the measurement data obtained in a validation experiment with the model predictions showed the great extrapolation capability of the model presented, which could provide new complementary information for the COMT production system.


Subject(s)
Catechol O-Methyltransferase/genetics , Bioreactors , Calibration , Catechol O-Methyltransferase/metabolism , Cell Division , Culture Media , Escherichia coli/cytology , Escherichia coli/enzymology , Escherichia coli/genetics , Humans , Kinetics , Models, Biological , Recombinant Proteins/metabolism , Temperature , Transfection
20.
Recenti Prog Med ; 99(6): 302-5, 2008 Jun.
Article in Italian | MEDLINE | ID: mdl-18710061

ABSTRACT

Obesity is an increasing condition spreading out in all of the world, independently by race, sex and age. Obesity in pregnancy represent a risk condition for both mother and her offspring. All of the studies are observational and show intervention strategies on weight gain improvement during gestational period, a current topic, but still controversial. Our study is based on nutritional dynamic monitoring during pregnancy in order to improve health and wellbeing status of both mother and her offspring, through an early and efficacy prevention.


Subject(s)
Energy Intake , Obesity/prevention & control , Pregnancy Complications/prevention & control , Weight Gain , Adult , Birth Weight , Body Mass Index , Female , Humans , Infant, Newborn , Monitoring, Physiologic/methods , Nutritional Requirements , Nutritional Status , Pregnancy , Prenatal Care , Retrospective Studies , Treatment Outcome , Young Adult
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