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1.
Sci Data ; 10(1): 471, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474611

RESUMO

In-situ marine cloud droplet number concentrations (CDNCs), cloud condensation nuclei (CCN), and CCN proxies, based on particle sizes and optical properties, are accumulated from seven field campaigns: ACTIVATE; NAAMES; CAMP2EX; ORACLES; SOCRATES; MARCUS; and CAPRICORN2. Each campaign involves aircraft measurements, ship-based measurements, or both. Measurements collected over the North and Central Atlantic, Indo-Pacific, and Southern Oceans, represent a range of clean to polluted conditions in various climate regimes. With the extensive range of environmental conditions sampled, this data collection is ideal for testing satellite remote detection methods of CDNC and CCN in marine environments. Remote measurement methods are vital to expanding the available data in these difficult-to-reach regions of the Earth and improving our understanding of aerosol-cloud interactions. The data collection includes particle composition and continental tracers to identify potential contributing CCN sources. Several of these campaigns include High Spectral Resolution Lidar (HSRL) and polarimetric imaging measurements and retrievals that will be the basis for the next generation of space-based remote sensors and, thus, can be utilized as satellite surrogates.

2.
Sci Rep ; 13(1): 7361, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147322

RESUMO

Viral infection of phytoplankton is a pervasive mechanism of cell death and bloom termination, which leads to the production of dissolved and colloidal organic matter that can be aerosolized into the atmosphere. Earth-observing satellites can track the growth and death of phytoplankton blooms on weekly time scales but the impact of viral infection on the cloud forming potential of associated aerosols is largely unknown. Here, we determine the influence of viral-derived organic matter, purified viruses, and marine hydrogels on the cloud condensation nuclei activity of their aerosolized solutions, compared to organic exudates from healthy phytoplankton. Dissolved organic material derived from exponentially growing and infected cells of well-characterized eukaryotic phytoplankton host-virus systems, including viruses from diatoms, coccolithophores and chlorophytes, was concentrated, desalted, and nebulized to form aerosol particles composed of primarily of organic matter. Aerosols from infected phytoplankton cultures resulted in an increase in critical activation diameter and average molar mass in three out of five combinations evaluated, along with a decrease in organic kappa (hygroscopicity) compared to healthy cultures and seawater controls. The infected samples also displayed evidence of increased surface tension depression at realistic cloud water vapor supersaturations. Amending the samples with xanthan gum to simulate marine hydrogels increased variability in organic kappa and surface tension in aerosols with high organic to salt ratios. Our findings suggest that the pulses of increased dissolved organic matter associated with viral infection in surface waters may increase the molar mass of dissolved organic compounds relative to surface waters occupied by healthy phytoplankton or low phytoplankton biomass.


Assuntos
Fitoplâncton , Viroses , Humanos , Fitoplâncton/metabolismo , Molhabilidade , Atmosfera , Água do Mar , Aerossóis
3.
J Affect Disord ; 330: 300-308, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36934855

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic compromised the mental health of COVID-19 patients and their family members. Due to social distancing and lockdown measures, a remote, tele-psychotherapy program for former or current COVID-19 patients and their relatives was implemented. OBJECTIVE: The primary goal of this project was to evaluate intervention feasibility. The secondary aim was to assess the impact of the intervention by means of pre-post psychological changes. METHODS: After a phone-based eligibility screening and remote neuropsychological testing, participants completed online self-reports assessing baseline COVID-related psychopathology. Next, participants attended eight tele-psychotherapy sessions. After treatment, the online self-reports were completed again. RESULTS: Of 104 enrolled participants, 88 completed the intervention (84.6 % completion rate). Significant pre-post improvements were observed for generalized anxiety (d = 0.38), depression (d = 0.37), insomnia (d = 0.43), post-traumatic psychopathology (d = 0.54), and general malaise (d = 0.31). Baseline cluster analysis revealed a subgroup of 41 subjects (47.6 %) with no psychopathology, and a second subgroup of 45 subject (52.3 %) with moderate severity. Thirty-three percent of the second group reached full symptom remission, while 66 % remained symptomatic after treatment. CONCLUSIONS: Remote brief tele-psychotherapy for COVID-19 patients and their first-degree relatives is feasible and preliminary efficacious at reducing COVID-related psychopathology in a subgroup of patients. Further research is needed to investigate distinct profiles of treatment response.


Assuntos
COVID-19 , Telemedicina , Humanos , SARS-CoV-2 , Psicoterapia , Estudos de Viabilidade , Controle de Doenças Transmissíveis
4.
JMIR Res Protoc ; 11(11): e39080, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36228130

RESUMO

BACKGROUND: The COVID-19 pandemic is negatively impacting the mental health of both patients with COVID-19 and the general population. As current guidelines are limiting in-person contacts to reduce the spread of the virus, the development of a digital approach to implement in psychiatric and psychological consultations is needed. In this paper, we present the DigiCOVID protocol, a digital approach to offer remote, personalized psychological and psychiatric support to former or current patients with COVID-19 and their relatives. OBJECTIVE: The main goal of this project is to evaluate the feasibility, acceptability, and usability of the DigiCOVID protocol. Furthermore, we also aim to assess the impact of the abovementioned protocol by means of pre-post changes in psychological clinical variables. METHODS: Participants undergo an initial telephonic screening to ensure inclusion criteria are met. Secondly, participants complete a video-assisted neuropsychological IQ test as well as web-based self-reports of health and general well-being. Participants are then assigned to a psychotherapist who offers 8 teletherapy sessions. At the end of the therapy cycle, the web-based questionnaires are administered for a posttreatment evaluation. RESULTS: As of April 2022, we enrolled a total of 122 participants, of which 94 have completed neuropsychological tests and web-based questionnaires. CONCLUSIONS: Our study aims at testing the feasibility and preliminary efficacy of DigiCOVID, a remote telemedicine protocol for the improvement of psychological and psychiatric health in patients with COVID-19 and their relatives. To date, the approach used seems to be feasible and highly customizable to patients' needs, and therefore, the DigiCOVID protocol might pave the way for future telepsychiatry-based interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT05231018; https://clinicaltrials.gov/ct2/show/NCT05231018?term=NCT05231018 &draw=2&rank=1. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/39080.

5.
Neuroimage Clin ; 36: 103179, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36088842

RESUMO

Obesity represents a risk factor for disability with a major bearing on life expectancy. Neuroimaging techniques are contributing to clarify its neurobiological underpinnings. Here, we explored whether structural brain abnormalities might accompany altered brain activations in obesity. We combined and compared data from brain activation studies for food stimuli and the data reported in structural voxel-based morphometry studies. We found that obese individuals have reduced grey matter density and functional activations in the thalamus and midbrain. A functional connectivity analysis based on these two clusters and its quantitative decoding showed that these regions are part of the reward system functional brain network. Moreover, we found specific grey matter hypo-densities in prefrontal cortex for the obese subjects, regions involved in controlled behaviour. These results support theories of obesity that point to reduced bottom-up reward processes (i.e., the Reward Deficit Theory), but also top-down theories postulating a deficit in cognitive control (i.e., the Inhibitory Control Deficit Theory). The same results also warrant a more systematic exploration of obesity whereby the reward of food and the intentional control over consummatory behaviour is manipulated.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Neuroimagem , Obesidade/diagnóstico por imagem , Recompensa , Mapeamento Encefálico
6.
Am J Ind Med ; 65(10): 790-799, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35985834

RESUMO

BACKGROUND: Comparison between cross-national job-exposure matrices (JEMs) may provide indications of their reliability, particularly if created using the same items. This study evaluated concordance between two JEMs created from United States (US) and Italian O*NET data, using job codes linked through international job codes. METHODS: Twenty-one physical exposures were obtained from the US and Italian O*NET databases. Italian O*NET items were direct translations of US O*NET items. Six hundred and eighty-four US and 586 Italian job codes were linked via crosswalks to 281 ISCO-08 job codes. A sensitivity study also assessed concordance on 258 jobs matched one-to-one across the two national job classifications. Concordance of US and Italian O*NET exposures was estimated by intraclass correlation coefficients (ICC) in multilevel models adjusted and not adjusted for country. RESULTS: ICCs showed moderate to poor agreement for all physical exposures in jobs linked through ISCO-08 codes. There was good to moderate agreement for 14 out of 21 exposures in models with one-to-one matched jobs between countries; greater agreement was found in all models adjusted for country. Exposure to whole-body vibration, time standing, and working outdoor exposed to weather showed the highest agreement. CONCLUSIONS: These results showed moderate to good agreement for most physical exposures across the two JEMs when US and Italian jobs were matched one-to-one and the analysis was adjusted for country. Job code assignments through crosswalks and differences in exposure levels between countries might greatly influence the observed cross-country agreement. Future multinational epidemiological studies should consider the quality of the cross-national job matching, and potential cross-national differences in exposure levels.


Assuntos
Exposição Ocupacional , Humanos , Descrição de Cargo , Exposição Ocupacional/análise , Ocupações , Reprodutibilidade dos Testes , Estados Unidos/epidemiologia
7.
Toxicol Appl Pharmacol ; 434: 115816, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856211

RESUMO

Most women with ovarian cancer are treated with chemotherapy before or after surgery. Unfortunately, chemotherapy treatment can cause negative side effects and the onset of multidrug resistance (MDR). The aim of this study is to evaluate the chemosensitizing effect of a natural compound, voacamine (VOA), in ovarian (A2780 DX) and colon (LoVo DX) cancer drug-resistant cell lines which overexpress P-glycoprotein (P-gp), in combination with paclitaxel (PTX), or doxorubicin (DOX) or 5-fluorouracil (5-FU). VOA, a bisindole alkaloid extracted from Peschiera fuchsiaefolia, has already been shown to be effective in enhancing the effect of doxorubicin, because it interferes with the P-gp function. Ovarian cancer cytotoxicity test shows that single treatments with VOA, DOX and PTX do not modify cell viability, while pretreatment with VOA, and then PTX or DOX for 72 h, induces a decrease. In colon cancer, since 5-FU is not a-substrate for P-gp, VOA has no sensitizing effect while in VOA + DOX there is a decrease in viability. Annexin V/PI test, cell cycle analysis, activation of cleaved PARP1 confirm that VOA plus PTX induce apoptotic cell death. Confocal microscopy observations show the different localization of NF-kB after treatment with VOA + PTX, confirming the inhibition of nuclear translocation induced by VOA pretreatment. Our data show the specific effect of VOA which only works on drugs known to be substrates of P-gp.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ibogaína/análogos & derivados , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Carcinoma Epitelial do Ovário/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias do Colo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ibogaína/química , Ibogaína/farmacologia , Estrutura Molecular
8.
Monaldi Arch Chest Dis ; 92(2)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34818884

RESUMO

This study describes the case of an 18-years-old male affected by severe COVID-19, who was receiving bilateral lung transplantation (LT), after 71 days of mechanical ventilation and 55 days of veno-venous extracorporeal membrane oxygenation. From post-operative day 2, early mobilization and physiotherapy treatments were performed. Weaning from mechanical ventilation, the use of non-invasive ventilation and tracheostomy management were included in the treatment. Forty-five days after LT the patient was discharged at home, showing improvements in terms of functional and respiratory parameters, quality of life and mood. While evidences about physiotherapy treatments in lung transplantation post severe COVID-19 remain limited, early approach and a multidisciplinary team may be considered key elements for functional recovery of these subjects.


Assuntos
COVID-19 , Transplante de Pulmão , Adolescente , Estado Terminal/terapia , Humanos , Masculino , Modalidades de Fisioterapia , Qualidade de Vida
9.
Chemistry ; 27(40): 10282-10292, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34058032

RESUMO

Alpha-amanitin, an extremely toxic bicyclic octapeptide extracted from the death-cap mushroom, Amanita phalloides, is a highly selective allosteric inhibitor of RNA polymerase II. Following on growing interest in using this toxin as a payload in antibody-drug conjugates, herein we report the synthesis and biochemical evaluation of several new derivatives of this toxin to probe the role of the trans-hydroxyproline (Hyp), which is known to be critical for toxicity. This structure activity relationship (SAR) study represents the first of its kind to use various Hyp-analogs to alter the conformational and H-bonding properties of Hyp in amanitin.


Assuntos
Alfa-Amanitina , Imunoconjugados , Amanita , Hidroxiprolina
10.
Ergonomics ; 64(11): 1379-1392, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33970812

RESUMO

This study aimed at determining the effect of a passive exoskeleton on local perceived discomfort, perceived effort and low back muscles' activity. Thirteen volunteers performed two simulated working tasks with and without the exoskeleton. In the static task, the exoskeleton decreased the lumbar perceived discomfort, the perceived effort and the level of low back muscles' activity (∼10%) while increasing discomfort in the chest and feet. The percent decrease in EMG amplitude was correlated with the percent increase in perceived effort with exoskeleton. For the dynamic task, the exoskeleton increased the discomfort in the chest and decreased the level of back muscle activity (∼5%). Current findings suggest exoskeleton is effective in reducing the back load while increasing the perceived discomfort at non-targeted body regions in both working tasks. The concurrent increase of discomfort in non-targeted areas probably led to a higher perceived effort despite the reduction of low back muscle activity. Practitioner summary: This study provided insights into exoskeleton effects on local discomfort, perceived effort and muscle activity. Overall, the potential benefits of passive exoskeleton should be considered alongside its adverse effects on the non-targeted body regions that can lead to an increase of perceived effort despite the reduction of back muscle activity.


Assuntos
Músculos do Dorso , Exoesqueleto Energizado , Fenômenos Biomecânicos , Eletromiografia , Humanos , Região Lombossacral , Músculo Esquelético , Tronco
11.
J Med Chem ; 64(7): 4117-4129, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33755471

RESUMO

Herein we describe the design and biological evaluation of a novel antitumor therapeutic platform that combines the most favorable properties of small-molecule drug conjugates (SMDCs) and antibody drug conjugates (ADCs). Although the small size of SMDCs, compared to ADCs, is an appealing feature for their application in the treatment of solid tumors, SMDCs usually suffer from poor pharmacokinetics, which severely limits their therapeutic efficacy. To overcome this limitation, in this proof-of-concept study we grafted an α-amanitin-based SMDC that targets prostate cancer cells onto an immunoglobulin Fc domain via a two-step "program and arm" chemoenzymatic strategy. We demonstrated the superior pharmacokinetic properties and therapeutic efficacy of the resulting Fc-SMDC over the SMDC in a prostate cancer xenograft mouse model. This approach may provide a general strategy toward effective antitumor therapeutics combining small size with pharmacokinetic properties close to those of an ADC.


Assuntos
Alfa-Amanitina/uso terapêutico , Antineoplásicos/uso terapêutico , Imunoconjugados/uso terapêutico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Alfa-Amanitina/química , Alfa-Amanitina/farmacocinética , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Imunoconjugados/imunologia , Imunoconjugados/farmacocinética , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/uso terapêutico , Masculino , Camundongos SCID , Neoplasias da Próstata/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Sci Total Environ ; 754: 142044, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254890

RESUMO

Sites with naturally high CO2 conditions provide unique opportunities to forecast the vulnerability of coastal ecosystems to ocean acidification, by studying the biological responses and potential adaptations to this increased environmental variability. In this study, we investigated the bivalve Ervilia castanea in coastal sandy sediments at reference sites and at volcanic CO2 seeps off the Azores, where the pH of bottom waters ranged from average oceanic levels of 8.2, along gradients, down to 6.81, in carbonated seawater at the seeps. The bivalve population structure changed markedly at the seeps. Large individuals became less abundant as seawater CO2 levels rose and were completely absent from the most acidified sites. In contrast, small bivalves were most abundant at the CO2 seeps. We propose that larvae can settle and initially live in high abundances under elevated CO2 levels, but that high rates of post-settlement dispersal and/or mortality occur. Ervilia castanea were susceptible to elevated CO2 levels and these effects were consistently associated with lower food supplies. This raises concerns about the effects of ocean acidification on the brood stock of this species and other bivalve molluscs with similar life history traits.


Assuntos
Bivalves , Dióxido de Carbono , Animais , Açores , Ecossistema , Humanos , Concentração de Íons de Hidrogênio , Água do Mar
13.
Ann Ist Super Sanita ; 56(4): 462-469, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33346172

RESUMO

INTRODUCTION: Turmeric is the common name for the rhizome of Curcuma longa L. In the recent years, food supplements containing turmeric have been marketed and widely used by an increasing number of consumers. Spontaneous reports of suspected adverse reactions to food supplements are collected within the Phytovigilance system. METHODS: An ad hoc multidisciplinary group investigated the suspected cases of hepatotoxicity reported to the Italian Phytovigilance system associated with the assumption of turmeric food supplements with the methodology specific to pharmacovigilance as well as for the evaluation of the quality and safety of food supplements. RESULTS: A cluster of 28 spontaneous reports of acute hepatitis, mostly with cholestasis, associated with turmeric products were sent to the Italian Phytovigilance system in the first six months of 2019. In all cases, except one, the causality assessment was at least possible. The suspected products were collected and analysed for the presence of drugs, heavy metals, aflatoxins, pesticides, synthetic dyes and pyrrolizidine alkaloids. CONCLUSION: On the basis of the results of all the activities performed by multidisciplinary group, regulatory intervention was taken. This study highlights the importance of developing an integrated evaluation approach for the evaluation of the adverse effects associated with the use of food supplements.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Curcuma/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Extratos Vegetais/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade
14.
Nanomaterials (Basel) ; 10(6)2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32575872

RESUMO

Cancer cells demonstrate elevated expression levels of the inhibitor of apoptosis proteins (IAPs), contributing to tumor cell survival, disease progression, chemo-resistance, and poor prognosis. Smac/DIABLO is a mitochondrial protein that promotes apoptosis by neutralizing members of the IAP family. Herein, we describe the preparation and in vitro validation of a synthetic mimic of Smac/DIABLO, based on fluorescent polyethylene glycol (PEG)-coated silica-core nanoparticles (NPs) carrying a Smac/DIABLO-derived pro-apoptotic peptide and a tumor-homing integrin peptide ligand. At low µM concentration, the NPs showed significant toxicity towards A549, U373, and HeLa cancer cells and modest toxicity towards other integrin-expressing cells, correlated with integrin-mediated cell uptake and consequent highly increased levels of apoptotic activity, without perturbing cells not expressing the α5 integrin subunit.

15.
Monaldi Arch Chest Dis ; 90(2)2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32573175

RESUMO

There is a need of consensus about the pulmonary rehabilitation (PR) in patients with COVID-19 after discharge from acute care. To facilitate the knowledge of the evidence and its translation into practice, we developed suggestions based on experts' opinion. A steering committee identified areas and questions sent to experts. Other international experts participated to a RAND Delphi method in reaching consensus and proposing further suggestions. Strong agreement in suggestions was defined when the mean agreement was >7 (1 = no agreement and 9 = maximal agreement). Panelists response rate was >95%. Twenty-three questions from 4 areas: Personnel protection equipment, phenotypes, assessments, interventions, were identified and experts answered with 121 suggestions, 119 of which received high level of concordance. The evidence-based suggestions provide the clinicians with current evidence and clinical experts opinion. This framework can be used to facilitate clinical decision making within the context of the individual patient. Further studies will evaluate the clinical usefulness of these suggestions.


Assuntos
Infecções por Coronavirus/reabilitação , Modalidades de Fisioterapia , Pneumonia Viral/reabilitação , Insuficiência Respiratória/reabilitação , Terapia Respiratória/métodos , Assistência Ambulatorial , Betacoronavirus , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/fisiopatologia , Técnica Delphi , Teste de Esforço , Humanos , Unidades de Terapia Intensiva , Itália , Estado Nutricional , Pandemias , Equipamento de Proteção Individual , Pneumonia Viral/complicações , Pneumonia Viral/fisiopatologia , Qualidade de Vida , Testes de Função Respiratória , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/fisiopatologia , SARS-CoV-2 , Transtornos de Estresse Pós-Traumáticos
16.
Toxicol In Vitro ; 65: 104819, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32135239

RESUMO

Search for natural substances in association with conventional chemotherapeutic drugs with a chemiosensitizing action easily accessible to the tumor mass has encouraged our studies on voacamine (VOA) and its monomeric units, voacangine and vobasine. Our previous results showed that VOA sensitized multidrug resistant (MDR) osteosarcoma cells (U-2 OS/DX) to doxorubicin (DOX) cytotoxicity. VOA, extracted by Peschiera fuchsiaefolia plant, is a bisindole alkaloid consisting of an Iboga skeleton (voacangine) directly linked to a 2-acyl indole unit (vobasine). High-performance thin-layer chromatography densitometry demonstrated the purity of VOA, voacangine and vobasine samples. Flow cytometry analysis showed that VOA, voacangine and vobasine enhanced DOX accumulation of U-2 OS/DX cells, in equally way, whereas VOA reduced more efficiently DOX efflux. Optical microscopy and clonogenic assay confirmed that VOA was more effective than voacangine and vobasine in enhancing DOX cytotoxic effect. These results showed that monomers linked together are necessary to modulate resistant phenotype of osteosarcoma cells. To complete the study, we evaluated the effect of three compounds on microtubules by confocal microscopy, suggesting that only the whole molecule depolymerizes the microtubules blocking so DOX efflux-mediated by vesicles.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ibogaína/análogos & derivados , Linhagem Celular Tumoral , Dimerização , Humanos , Ibogaína/farmacologia , Microscopia Confocal , Microtúbulos/efeitos dos fármacos
17.
Foods ; 8(8)2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31357632

RESUMO

A comparison between High-Performance Thin-Layer Chromatography (HPTLC) analysis and Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS), coupled with Principal Component Analysis (PCA) was carried out by performing a combined metabolomics study to discriminate Arbutus unedo (A. unedo) plants. For a rapid digital record of A. unedo extracts (leaves, yellow fruit, and red fruit collected in La Maddalena and Sassari, Sardinia), HPTLC was used. Data were then analysed by PCA with the results of the ability of this technique to discriminate samples. Similarly, extracts were acquired by non-targeted LC-HRMS followed by unsupervised PCA, and then by LC-HRMS (MS) to identify secondary metabolites involved in the differentiation of the samples. As a result, we demonstrated that HPTLC may be applied as a simple and reliable untargeted approach to rapidly discriminate extracts based on tissues and/or geographical origins, while LC-HRMS could be used to identify which metabolites are able to discriminate samples.

18.
J Pharm Biomed Anal ; 150: 121-131, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29247959

RESUMO

The marketing of new argan-based products is greatly increased in the last few years and consequently, it has enhanced the number of control analysis aimed at detecting counterfeit products claiming argan oil as a major ingredient. Argan oil is produced in Morocco and it is quite expensive. Two simple methods for the rapid screening of pure oil and argan-oil based products, focused on the analysis of the triacylglycerol profile, have been developed. A three-minute-run by UHPLC-PDA allows the identification of a pure argan oil, while the same run with the MS detector allows also the analysis of products containing the oil down to 0.03%. On the other hand, by HPTLC the simultaneous analysis of twenty samples, containing argan oil down to 0.5%, can be carried out in a forty-five-minute run. The triglyceride profile of the most common vegetable fats such as almond, coconut, linseed, wheat germ, sunflower, peanut, olive, soybean, rapeseed, hemp oils as well as shea butter used either in cosmetics or commonly added for the counterfeiting of argan oil, has been also investigated. Over sixty products with different formulations and use have been successfully analyzed and argan oil in the 2.4-0.06% concentration range has been quantified. The methods are suitable either for a rapid screening or for quantifying argan oil in different formulations.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Óleos de Plantas/análise , Triglicerídeos/análise , Óleos de Plantas/química , Óleos de Plantas/normas , Espectrometria de Massas por Ionização por Electrospray/métodos , Fatores de Tempo , Triglicerídeos/química
19.
Biosens Bioelectron ; 93: 52-56, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27743865

RESUMO

In this work, we developed an impedimetric label-free immunosensor for the detection of 2,4-Dichlorophenoxy Acetic Acid (2,4-D) herbicide either in standard solution and spiked real samples. For this purpose, we prepared by electropolymerization a conductive polymer poly-(aniline-co-3-aminobenzoic acid) (PANABA) then we immobilized anti-2,4-D antibody onto a nanocomposite AuNPs-PANABA-MWCNTs employing the carboxylic moieties as anchor sites. The nanocomposite was synthesized by electrochemical polymerization of aniline and 3-aminobenzoic acid, in the presence of a dispersion of gold nanoparticles, onto a multi-walled carbon nanotubes-based screen printed electrode. Aniline-based copolymer, modified with the nanomaterials, allowed to enhance the electrode conductivity thus obtaining a more sensitive antigen detection. The impedimetric measurements were carried out by electrochemical impedance spectroscopy (EIS) in faradic condition by using Fe(CN)63-/4- as redox probe. The developed impedimetric immunosensor displayed a wide linearity range towards 2,4-D (1-100ppb), good repeatability (RSD 6%), stability and a LOD (0.3ppb) lower than herbicide emission limits.


Assuntos
Ácido 2,4-Diclorofenoxiacético/isolamento & purificação , Técnicas Biossensoriais , Técnicas Eletroquímicas , Ácido 2,4-Diclorofenoxiacético/química , Compostos de Anilina/química , Espectroscopia Dielétrica , Eletrodos , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Polímeros/química
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