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1.
Neural Comput ; 36(4): 677-704, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38457764

RESUMO

Representing a scene and its constituent objects from raw sensory data is a core ability for enabling robots to interact with their environment. In this letter, we propose a novel approach for scene understanding, leveraging an object-centric generative model that enables an agent to infer object category and pose in an allocentric reference frame using active inference, a neuro-inspired framework for action and perception. For evaluating the behavior of an active vision agent, we also propose a new benchmark where, given a target viewpoint of a particular object, the agent needs to find the best matching viewpoint given a workspace with randomly positioned objects in 3D. We demonstrate that our active inference agent is able to balance epistemic foraging and goal-driven behavior, and quantitatively outperforms both supervised and reinforcement learning baselines by more than a factor of two in terms of success rate.

2.
Interface Focus ; 13(3): 20220077, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37065264

RESUMO

Humans perceive and interact with hundreds of objects every day. In doing so, they need to employ mental models of these objects and often exploit symmetries in the object's shape and appearance in order to learn generalizable and transferable skills. Active inference is a first principles approach to understanding and modelling sentient agents. It states that agents entertain a generative model of their environment, and learn and act by minimizing an upper bound on their surprisal, i.e. their free energy. The free energy decomposes into an accuracy and complexity term, meaning that agents favour the least complex model that can accurately explain their sensory observations. In this paper, we investigate how inherent symmetries of particular objects also emerge as symmetries in the latent state space of the generative model learnt under deep active inference. In particular, we focus on object-centric representations, which are trained from pixels to predict novel object views as the agent moves its viewpoint. First, we investigate the relation between model complexity and symmetry exploitation in the state space. Second, we do a principal component analysis to demonstrate how the model encodes the principal axis of symmetry of the object in the latent space. Finally, we also demonstrate how more symmetrical representations can be exploited for better generalization in the context of manipulation.

3.
Int J Mol Sci ; 24(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37108592

RESUMO

Cr(VI) is highly soluble and mobile in water solution and extremely toxic. In order to obtain a specific material with adsorption properties towards Cr(VI), and that can be used in environmental remediation of water contaminated with Cr(VI), one-step sol-gel technique, at low temperature (50 °C), has been optimized to prepare transparent silica-based xerogel monolith by using tetraethyl orthosilicate as precursor. The obtained xerogel, with disk shape, was fully characterized by Raman, BET, FE-SEM and XRD analysis. The results indicated that the material showed silica amorphous phase and high porosity. The study of the adsorption properties towards different concentrations of Cr(VI), in the form of HCrO4- in acidic condition, showed prominent results. The absorption kinetics were evaluated by studying different models, the final result showing that the absorption of Cr(VI) occurred through intra-particle diffusion process, following two steps, and that the absorption equilibrium is regulated by Freundlich isotherm model. The material can be restored by reducing the hazardous Cr(VI) to Cr(III), a less toxic form of chromium, by 1,5-diphenylcarbazide, and with successive treatment in acidic water.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Água , Poluentes Químicos da Água/análise , Dióxido de Silício , Descontaminação , Cromo/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Purificação da Água/métodos
4.
Antioxidants (Basel) ; 12(4)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37107191

RESUMO

Wine lees are sediments deposited on the walls and bottom of barrels resulting from wine fermentation and mainly consist of yeasts. Saccharomyces cerevisiae extracts, rich in beneficial components for the skin, have already been used in cosmesis, while wine lees have not been well exploited by the cosmetics industry yet. The aim of this work was the full characterization of the wine lees from Verdicchio's wine, with the aim to exploit it as a beneficial ingredient in new cosmetic products. After mapping the microbial composition of the sample waste, the parameters for the sonication extraction process were optimized and the physicochemical properties of the extract were analyzed. The efficiency of the aqueous extraction-and in particular the yeast cell lysis necessary for the release of proteins from the cell-was assessed by evaluating cell shape and size, and protein release, under scanning electron microscopy (SEM), dynamic light scattering (DLS) and Bradford's protein assays. Thus, the total phenol content and antioxidant capacity of the supernatant recovered from native and sonicated lees were determined by Folin-Ciocalteu's and spectrophotometric assays, respectively. To quantify the heavy metals and highlight the presence of microelements beneficial for the skin, inductively coupled plasma-mass spectrometry (ICP-MS) was applied. In vitro metabolic activity and cytotoxicity were tested on both HaCat keratinocytes and human gingival fibroblasts, showing that wine lees are safe for skin's cells. The results show that sonicated lees appear to be more interesting than native ones as a consequence of the release of the active ingredients from the cells. Due to the high antioxidant capacity, content of beneficial elements for skin and an appropriate microbiologic profile, wine lees were included in five new solid cosmetic products and tested for challenge test, compatibility with human skin, sensory analysis, trans epidermal water loss (TEWL) and sebometry.

5.
J Crit Care Med (Targu Mures) ; 8(4): 292-295, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36474615

RESUMO

Introduction: In patients admitted to the Intensive Care Unit (ICU), sepsis can lead to acute kidney injury (AKI), which may require the initiation of continuous renal replacement therapy (CRRT) in 15-20% of cases. There is no consensus about the best extracorporeal treatment to choose in septic patients with AKI. Case presentation: We describe the case of a 70-year-old woman admitted to the ICU with a severe endotoxin septic shock due to Neisseria meningitidis serogroup C. Despite prompt medical intervention, including fluid resuscitation, high dose vasopressor, inotrope support, and broad-spectrum antimicrobial treatment, in a few hours patient's haemodynamic worsened and she developed multi-organ failure, including severe AKI, requiring CRRT. So, continuous veno-venous haemodiafiltration was started, using an oXiris® haemodiafilter set, in series with an adsorber device (CytoSorb®). After 48 hours of this combined extracorporeal treatment, haemodynamic parameters improved, allowing a significant reduction of the vasoactive therapy, with a concomitant decrease in endotoxin and inflammatory markers serum levels. In the following days patient's conditions still improved and renal function recovered. Conclusions: Timely extracorporeal blood purification therapy, using a double haemoadsorption device, may be effective in the management of severe septic shock.

6.
Sensors (Basel) ; 22(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36236477

RESUMO

The robotics field has been deeply influenced by the advent of deep learning. In recent years, this trend has been characterized by the adoption of large, pretrained models for robotic use cases, which are not compatible with the computational hardware available in robotic systems. Moreover, such large, computationally intensive models impede the low-latency execution which is required for many closed-loop control systems. In this work, we propose different strategies for improving the computational efficiency of the deep-learning models adopted in reinforcement-learning (RL) scenarios. As a use-case project, we consider an image-based RL method on the synergy between push-and-grasp actions. As a first optimization step, we reduce the model architecture in complexity, by decreasing the number of layers and by altering the architecture structure. Second, we consider downscaling the input resolution to reduce the computational load. Finally, we perform weight quantization, where we compare post-training quantization and quantized-aware training. We benchmark the improvements introduced in each optimization by running a standard testing routine. We show that the optimization strategies introduced can improve the computational efficiency by around 300 times, while also slightly improving the functional performance of the system. In addition, we demonstrate closed-loop control behaviour on a real-world robot, while processing everything on a Jetson Xavier NX edge device.


Assuntos
Robótica , Algoritmos , Força da Mão , Robótica/métodos
7.
G Ital Nefrol ; 39(4)2022 Aug 29.
Artigo em Italiano | MEDLINE | ID: mdl-36073337

RESUMO

Campylobacteriosis is caused by Gram bacteria. Most common species are C. jejuni and C. coli. Campylobacteriosis is a rare cause of sepsis, and in some European countries it is more common than salmonellosis, becoming a public health problem. We have treated a 66-year-old patient, hypertensive, ischemic cardiopathic, scheduled for coronary angiography, hospitalized with AKI, in a state of shock after some days of acute diarrhea. Because of the pathogen's seasonal nature and the patient's clinical features, in addition to common coproculture also Campylobacter has been sought, and found. Treated with volume repletion and antibiotics, within one week normal kidney functions were fully restored. He had a coronary angiography a week after being discharged from the hospital.


Assuntos
Infecções por Campylobacter , Campylobacter , Idoso , Antibacterianos/uso terapêutico , Infecções por Campylobacter/complicações , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/tratamento farmacológico , Diarreia/microbiologia , Europa (Continente) , Humanos , Masculino
8.
Eur Heart J Cardiovasc Pharmacother ; 8(3): 291-301, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-34351426

RESUMO

AIMS: There is a lack of evidence regarding the benefits of ß-blocker treatment after invasively managed acute myocardial infarction (MI) without reduced left ventricular ejection fraction (LVEF). METHODS AND RESULTS: The tREatment with Beta-blockers after myOcardial infarction withOut reduced ejection fracTion (REBOOT) trial is a pragmatic, controlled, prospective, randomized, open-label blinded endpoint (PROBE design) clinical trial testing the benefits of ß-blocker maintenance therapy in patients discharged after MI with or without ST-segment elevation. Patients eligible for participation are those managed invasively during index hospitalization (coronary angiography), with LVEF >40%, and no history of heart failure (HF). At discharge, patients will be randomized 1:1 to ß-blocker therapy (agent and dose according to treating physician) or no ß-blocker therapy. The primary endpoint is a composite of all-cause death, non-fatal reinfarction, or HF hospitalization over a median follow-up period of 2.75 years (minimum 2 years, maximum 3 years). Key secondary endpoints include the incidence of the individual components of the primary composite endpoint, the incidence of cardiac death, and incidence of malignant ventricular arrhythmias or resuscitated cardiac arrest. The primary endpoint will be analysed according to the intention-to-treat principle. CONCLUSION: The REBOOT trial will provide robust evidence to guide the prescription of ß-blockers to patients discharged after MI without reduced LVEF.


Assuntos
Infarto do Miocárdio , Disfunção Ventricular Esquerda , Antagonistas Adrenérgicos beta/efeitos adversos , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/tratamento farmacológico , Estudos Prospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/tratamento farmacológico , Função Ventricular Esquerda
9.
J Subst Abuse Treat ; 125: 108317, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34016302

RESUMO

Exposure to smoking-related stimuli may induce the reconsolidation of smoking-related memories in smokers. Research has proposed that extinction applied after the retrieval of a smoking memory may inhibit reconsolidation and prevent craving. The aim of this study was to test the effect of postretrieval extinction (PRE) on the reconsolidation of smoking memory by using a virtual reality (VR) simulation in smokers. On the day 1 session, the study exposed 46 smokers to a neutral and then to a smoking VR scenario under a fixed-block protocol. On day 2, the study randomized participants into three groups (G) and exposed them to a 15-s VR immersion in smoking (G1, G3) or neutral (G2) scenario for memory retrieval. After 15 min, the study exposed G1 and G2 to a VR PRE during the temporal window of memory vulnerability, whereas the study exposed G3 to extinction immediately after retrieval. On day 3, the study exposed all groups to neutral and smoking scenarios similar to day 1. All groups significantly increased craving for cigarettes after exposure to the smoking scenario on day 1 (p < 0.01). On day 3, VR PRE after a 15-second VR smoking memory retrieval was able to inhibit reconsolidation in G1, but not in G3 exposed to PRE before the window of vulnerability, or in G2 not exposed to the smoking memory retrieval. These findings show the superiority of VR PRE after smoking memory retrieval compared to a standard extinction procedure.


Assuntos
Realidade Virtual , Fissura , Humanos , Fumantes , Fumar , Fumar Tabaco
10.
Eur Addict Res ; 27(6): 439-446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33940577

RESUMO

INTRODUCTION: Although the effects of proximal smoking cues have been widely studied in smokers, little is known on the features associated with background spatial context effect, that is, "context reactivity." The aim of this study was to investigate context reactivity exhibited by smokers in virtual cue-free domestic scenarios. METHODS: Sixty-nine participants divided in 2 cohorts (33 smokers and 36 non-smokers) were exposed to a virtual reality session with 4 domestic room scenarios presented in a balanced order: bedroom, bathroom, kitchen, and living room. RESULTS: We showed that (i) it is possible to elicit smoking craving in smokers in virtual reality, and (ii) these effects are room dependent and (iii) associated with a lower sense of presence; furthermore, (iv) smokers reported higher craving scores for alcohol and food in a room-dependent fashion compared to non-smokers. CONCLUSION: Our study provides an experimental paradigm for assessing context reactivity in smokers and suggests a potential use for the identification of non-pharmacological interventions as a co-adjuvant of smoking cessation treatment.


Assuntos
Fumantes , Abandono do Hábito de Fumar , Fissura , Sinais (Psicologia) , Humanos , Fumar , Fumar Tabaco
11.
Antioxidants (Basel) ; 9(5)2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32365615

RESUMO

The purpose of this work was the optimization of the extraction from spent coffee grounds, specifically 100% Arabica coffee blends, using a desirability approach. Spent coffees were recovered after the preparation of the espresso coffee under the typical conditions used in coffee bars with a professional machine. Spent coffee was subjected to different extraction procedures in water: by changing the extraction temperature (60, 80, or 100 °C) and the solvent extraction volume (10, 20, 30 mL for 1 gram of coffee) and by maintaining constant the extraction time (30 minutes). The ranges of the process parameters, as well as the solvent to be used, were established by running preliminary experiments not reported here. The variables of interest for the experimental screening design were the content of caffeine, trigonelline, and nicotinic acid, quantitatively determined from regression lines of standard solutions of known concentrations by a validated HPLC-VWD method. Since solvent extraction volumes and temperatures were revealed to be the most significant process variables, for the optimization of the extraction process, an approach based on Response Surface Methodology (RSM) was considered. In particular, a Box-Wilson Central Composite Design, commonly named central composite design (CCD), was used to find the optimal conditions of the extraction process. Moreover, the desirability approach was then applied to maximize the extraction efficiency by searching the optimal values (or at least the best compromise solution) for all three response variables simultaneously. Successively, the best extract, obtained in a volume of 20 mL of water at an extraction temperature of 80 °C, was analyzed for total phenol content (TPC) through the Folin-Ciocalteu assay, and the antioxidant capacities (AC) through the trolox equivalent (TE) antioxidant capacity (DPPH), ferric-ion reducing antioxidant parameter (FRAP), and radical cation scavenging activity and reducing power (ABTS). The TPC and the AC for spent coffee were high and comparable to the results obtained in previous similar studies. Then, the extract was evaluated by inductively coupled plasma mass spectrometry (ICP-MS), revealing that potassium was the most abundant element, followed by phosphorus, magnesium, calcium, sodium, and sulfur, while very low content in heavy metals was observed. Preliminary in vitro assays in keratinocyte HaCaT cells were carried out to assess the safety, in terms of cytotoxicity of spent coffee, and results showed that cell viability depends on the extract concentration: cell viability is unmodified up to a concentration of 0.3 mg/mL, over which it becomes cytotoxic for the cells. Spent coffee extract at 0.03 and 0.3 mg/mL showed the ability to reduce intracellular reactive oxygen species formation induced by hydrogen peroxide in HaCaT cells, suggesting its antioxidant activity at intracellular levels.

12.
G Ital Cardiol (Rome) ; 21(6): 417-420, 2020 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-32425184

RESUMO

Takotsubo syndrome (TTS) is one of the causes of myocardial infarction with non-obstructive coronary arteries, and is often triggered by physical events (e.g. acute respiratory failure), or emotional events (e.g. loss of a family member, cardiac stress induced by an acute illness). SARS-CoV-2 pneumonia currently represents a worldwide health problem; the correlations between cardiovascular disease, myocardial injury and SARS-CoV-2 infection are still unclear, but initial data show that myocardial damage represents a negative prognostic factor. Myocardial injury during SARS-CoV-2, as defined by a pathological rise in circulating troponin levels, is not an uncommon complication in hospitalized patients, and is significantly more frequent in intensive care unit patients and among those who died. In this setting, myocardial injury is mainly secondary to type 2 myocardial infarction (mismatch in myocardial oxygen supply and demand during respiratory failure); other causes include myocarditis, coronary thrombosis, sepsis or septic shock. At present, only few cases of TTS have been described during SARS-CoV-2. Here we report the case of a patient hospitalized for pneumonia and respiratory failure due to SARS-CoV-2 with subsequent onset of TTS triggered by both physical and emotional events.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/complicações , Infarto do Miocárdio/etiologia , Pneumonia Viral/complicações , Cardiomiopatia de Takotsubo/etiologia , Betacoronavirus/isolamento & purificação , COVID-19 , Feminino , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/virologia , Pandemias , Prognóstico , SARS-CoV-2 , Cardiomiopatia de Takotsubo/virologia
13.
Antioxidants (Basel) ; 9(4)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316684

RESUMO

Chemical and sensory peculiarities of monovarietal extra virgin olive oils (MEVOOs) from the cultivars (cvs.) Ascolana tenera (ASC), Coroncina (COR), Mignola (MIG), Piantone di Mogliano (MOG), and Raggia (RAG) from Marche region (Italy) are investigated. Their polar phenolic substances and α-tocopherol are analysed through high performance liquid chromatography with different detectors. Volatile substances, fatty acid composition, and squalene are analysed by gas chromatography coupled to mass spectrometry (MS) and to the flame ionization detector, respectively. Total antioxidant activity and sensory analysis were also performed. MOG showed high squalene content (on average 0.88 ± 0.16 g/100 g), high relative amount of α-copaene among volatiles, and the highest oleic acid percentage. MIG had high α-tocopherol content (on average 350.0 ± 57.6 mg kg-1) and high α-farnesene in the volatile fraction. ASC showed the highest sensory quality and the lignan pinoresinol with higher concentration as compared to the other MEVOOs (p < 0.05), which resulted in a possible chemical marker for this cv. RAG was characterized by the sensory note of almond, which corresponds to its highest (E)-2-hexenal percentage. Sensory analysis and an antioxidant activity assay performed on a set of industrial extra virgin olive oils purchased in supermarkets, highlighted MEVOOs' superiority from these points of view. Principal component analysis displays the main characteristics of the cvs. investigated.

14.
J Avian Med Surg ; 33(2): 179-183, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251506

RESUMO

A necropsy was conducted on a female grey-headed parrot (Poicephalus robustus suahelicus) that died following signs of depression, ruffled feathers, and inappetence. Microscopic examination revealed the presence of hemoprotozoa in the liver. A nested polymerase chain reaction (PCR), targeting the mitochondrial cytochrome b gene of Haemoproteus species, Plasmodium species, and Leucocytozoon species, was performed on frozen tissue samples collected at necropsy. The hemoprotozoa were identified by PCR analysis as Leucocytozoon species. Hemoprotozoa are rarely reported in African parrots, and this is the first report of a Leucocytozooon species infection in a Poicephalus robustus suahelicus.


Assuntos
Doenças das Aves/parasitologia , Haemosporida , Papagaios , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/patologia , Evolução Fatal , Feminino , Infecções Protozoárias em Animais/patologia
15.
Int J Food Sci Nutr ; 70(7): 796-812, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30892113

RESUMO

In the present work, we reported for the first time a comprehensive study on the phytonutrients, that is, natural compounds able to provide benefits to health, found in an ancient apple variety cultivated in orchards of the Sibillini Mountains, central Italy, known as Mela Rosa dei Monti Sibillini. This fruit has recently been promoted by authorities and local institutions as a typical food of the Marche Region. For the purpose, analysis of its nutrients, phenolics, triterpenes and volatile components as well as a morpho-anatomical study was carried out in order to give an added value for its consumption and promotion at regional and national level. ICP-MS, HPLC-MSn and GC-MS analyses were useful techniques for giving a typical fingerprint to this apple, consisting in a high content of K and B, quercetin derivatives as the main phenolic compounds and carboxylic esters, aldehydes, alcohols and (E,E)-α-farnesene as the main key odorants.


Assuntos
Frutas/química , Malus/química , Nutrientes/análise , Compostos Fitoquímicos/análise , Polifenóis/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Líquida de Alta Pressão , Ésteres/análise , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Itália , Malus/classificação , Valor Nutritivo , Odorantes/análise , Fenóis/análise , Triterpenos/análise
16.
Eur J Med Chem ; 155: 418-427, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29906688

RESUMO

Basal like breast cancer (BLBC) is a very aggressive subtype of breast cancer giving few chances of survival, against which cisplatin based therapy is a compromise among the anticancer activity, the resistance development and the severe side effects. With the aim of finding new anticancer agents alternative to cisplatin, seven gold(I) azolate/phosphane compounds were evaluated in vitro by MTT tests in human MDA-MB-231, human mammary epithelial HMLE cells overexpressing FoxQ1, and murine A17 cells as models of BLBC. Two compounds, (4,5-dichloro-1H-imidazolate-1-yl)-(triphenylphosphane)-gold(I) 1 and (4,5-dicyano-1H-imidazolate-1-yl)-(triphenylphosphane)-gold(I) 2 were found very active and chosen for an in vivo study in A17 tumors transplanted in syngeneic mice. The compounds resulted to be more active than cisplatin, less nephrotoxic and generally more tolerated by the mice. This study also provides evidence that both gold(I) complexes inhibited the 19 S proteasome-associated deubiquitinase USP14 and induced apoptosis, while compound 1's mechanism of action depends also on its ability to down-regulate key molecules governing cancer growth and progression, such as STAT3 and Cox-2.


Assuntos
Antineoplásicos/farmacologia , Azóis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Compostos Organoáuricos/farmacologia , Fosfinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Azóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Compostos Organoáuricos/síntese química , Compostos Organoáuricos/química , Fosfinas/química , Relação Estrutura-Atividade
18.
Food Chem ; 221: 473-481, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979230

RESUMO

In the present work, we studied the chemical composition of Chinese artichoke (S. affinis tubers) by analyzing its polar constituents and its macro- and micro- nutrients. A total of nine compounds were isolated from the tuber ethanolic extract and structurally elucidated by Nuclear Magnetic Resonance (NMR) spectroscopy and mass spectrometry (MS). The marker compounds identified were oligosaccharide stachyose and the organic acid, succinic acid, as well as phenylethanoid and iridoid glycosides. The macronutrient profile was dominated by carbohydrates (36.9% dw), whereas potassium (2.36%) was the most abundant micro-nutrient. The tuber ethanolic extract was able to efficiently protect human cells (Caco-2, SHSY-5Y and K562) against t-BHP-induced oxidative damage.


Assuntos
Glicosídeos Iridoides/análise , Extratos Vegetais/química , Espécies Reativas de Oxigênio/análise , Stachys/química , Ácido Succínico/análise , Células CACO-2 , Humanos , Espectroscopia de Ressonância Magnética , Valor Nutritivo
19.
ACS Appl Mater Interfaces ; 8(43): 29676-29687, 2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27762551

RESUMO

Novel composite materials PEn (n = 1-9) have been prepared by an easily up-scalable embedding procedure of three different families of Ag(I) acylpyrazolonato complexes in polyethylene (PE) matrix. In details, PE1-PE3 composites contain polynuclear [Ag(QR)]n complexes, PE4-PE6 contain mononuclear [Ag(QR)(L)m] complexes and PE7-PE9 are loaded with mononuclear [Ag(QR) (PPh3)2] complexes, respectively (where L = 1-methylimidazole or 2-ethylimidazole, m = 1 or 2, and HQR = 1-phenyl-3-methyl-4-RC(═O)-5-pyrazolone, where in detail HQfb, R = -CF2CF2CF3; HQcy, R = -cyclo-C6H11; HQbe, R = -C(H)═C(CH3)2). The PEn composites, prepared by using a 1:1000 w/w silver additive/polyethylene ratio, have been characterized in bulk by IR spectroscopy and TGA analyses, which confirmed that the properties of polyethylene matrix are essentially unchanged. AFM, SEM, and EDX surface techniques show that silver additives form agglomerates with dimensions 10-100 µm on the polyethylene surface, with a slight increment of surface roughness of pristine plastic within 50 nm. However, the elastic properties of the composites are essentially the same of PE. The antibacterial activity of all composites has been tested against three bacterial strains (E. coli, P. aeruginosa and S. aureus) and results show that two classes of composites, PE1-PE3 and PE4-PE6, display high and persistent bactericidal and bacteriostatic activity, comparable to PE embedded with AgNO3. By contrast, composites PE7-PE9 exhibit a reduced antibacterial action. Contact and release tests in several conditions for specific migration of Ag+ from plastics, indicate a very limited but time persistent release of silver ions from PE1-PE6 composites, thus suggesting that they are potential antibacterial materials for future applications. Instead, PE7-PE9 almost do not release silver, only trace levels of silver ions being detected, in accordance with their reduced antibacterial action. None of the composites is toxic against higher organisms, as confirmed by D. magna test of ecotoxicity.


Assuntos
Polietileno/química , Antibacterianos , Escherichia coli , Prata , Staphylococcus aureus
20.
Pharmacol Res ; 107: 282-290, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27038531

RESUMO

Ruthenium compounds have become promising alternatives to platinum drugs by displaying specific activities against different cancers and favorable toxicity and clearance properties. Here, we show that the ruthenium(II) complex [Ru(p-cymene)(bis(3,5-dimethylpyrazol-1-yl)methane)Cl]Cl (UNICAM-1) exhibits potent in vivo antitumor effects. When administered as four-dose course, by repeating a single dose (52.4mgkg-1) every three days, UNICAM-1 significantly reduces the growth of A17 triple negative breast cancer cells transplanted into FVB syngeneic mice. Pharmacokinetic studies indicate that UNICAM-1 is rapidly eliminated from kidney, liver and bloodstream thanks to its high hydrosolubility, exerting excellent therapeutic activity with minimal side effects. Immunohistological analysis revealed that the efficacy of UNICAM-1, mainly relies on its capacity to reverse tumor-associated immune suppression by significantly reducing the number of tumor-infiltrating regulatory T cells. Therefore, UNICAM-1 appears very promising for the treatment of TNBC.


Assuntos
Antineoplásicos/uso terapêutico , Compostos Organometálicos/uso terapêutico , Rutênio/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Compostos Organometálicos/sangue , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/farmacologia , Rutênio/sangue , Rutênio/farmacocinética , Rutênio/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/efeitos dos fármacos
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