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1.
Colloids Surf B Biointerfaces ; 212: 112363, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35123194

RESUMO

Given their large surface area and versatile chemical reactivity, single-walled carbon nanotubes (SWCNTs) are regarded as the basis of new pharmacological complexes. In this study, SWCNTs are chemically functionalized with fluorescein, folic acid, and capecitabine, a drug that is commonly used against colorectal cancer. These functionalized SWCNTs are dispersed in water by taking advantage of their synergistic interaction with type-II nanocrystalline cellulose (II-NCC), and the resulting colloidal system is tested in vitro on both normal (differentiated) and cancerous (proliferative) human colon cells (Caco-2). The functionalized SWCNT/II-NCC hybrids show a higher activity than the reference (capecitabine) against the Caco-2 cancer cell line. However, this effect appears to be intrinsically associated with the SWCNT/II-NCC complex, particularly boosted by fluorescein, as the presence of capecitabine is not required. In addition, confocal microscopy fluorescence imaging using cell cultures highlights the enormous potential of this nanohybrid platform for colon cancer theranostics.


Assuntos
Neoplasias do Colo , Nanotubos de Carbono , Células CACO-2 , Celulose , Neoplasias do Colo/tratamento farmacológico , Humanos , Nanotubos de Carbono/química
6.
Am Heart J ; 220: 127-136, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31809992

RESUMO

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Catheter ablation aims to restore sinus rhythm. However, relapses occur in up to 30% of patients. A Mediterranean diet (MedDiet) enriched with extra-virgin olive oil (EVOO) substantially reduced the incidence of AF in the PREDIMED trial. The PREDIMAR will test a similar intervention in secondary prevention. Methods: PREDIMAR is a multicenter, randomized, single-blind trial testing the effect of a MedDiet enriched with EVOO to reduce tachyarrhythmia relapses after AF ablation. The primary outcome is the recurrence of any sustained atrial tachyarrhythmia after ablation (excluding those occurring only during the first 3 months after ablation). The target final sample size is 720 patients (360 per group) recruited from 4 Spanish hospitals. A remote intervention, maintained for 2 years, is delivered to the active intervention group including periodic phone calls by a dietitian and free provision of EVOO. The control group will receive delayed intervention after trial completion. Routine electrocardiogram (ECG) and Holter ECG are performed, and a portable cardiac rhythm monitoring device is provided to be worn by participants during 15 months. Results: Recruitment started in March 2017. Up to July 2019, 609 patients were randomized (average inclusion rate: 5.3 patients/wk). Retention rates after 18 months are >94%. Conclusions: If our hypothesis is confirmed, the utility of the MedDiet enriched with EVOO in slowing the progression of AF will be proven, preventing recurrences and potentially reducing complications.


Assuntos
Fibrilação Atrial/prevenção & controle , Fibrilação Atrial/cirurgia , Dieta Mediterrânea , Azeite de Oliva/uso terapêutico , Prevenção Secundária/métodos , Ablação por Cateter , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Recidiva , Método Simples-Cego , Taquicardia/prevenção & controle , Fatores de Tempo
8.
Chem Commun (Camb) ; 54(17): 2086-2089, 2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29334096

RESUMO

A non-conventional modification of exfoliated few-layer graphene (FLG) with different arynes under microwave (MW) irradiation and solvent-free conditions is reported. The described approach allows reaching fast, efficient and mild covalent functionalization of FLG.

10.
J Mater Chem B ; 5(32): 6681-6687, 2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32264431

RESUMO

Prostate-specific membrane antigen (PSMA), a glycoprotein expressed in the prostatic epithelium endowed with enzymatic activity, is a very promising diagnostic marker for the early detection of prostate cancer. In this study, we report a novel electrochemiluminescence ELISA-like immunosensor based on carbon nanotubes and a highly specific sandwich immunoassay for the PSMA detection. To fabricate the device, an optically transparent electrode was modified with doubly functionalized multi-walled carbon nanotubes carrying amine groups and a monoclonal anti-PSMA antibody. Subsequently, to complete the sandwich immunosensing device, a second specific monoclonal anti-PSMA antibody was labelled with a electrochemiluminescent probe. Under optimized experimental conditions, the proposed sensing device exhibits a performance exceeding that of the state of-the-art in terms of the limit of detection (LOD) and limit of quantification (LOQ) as good as 0.88 ng mL-1 and 2.60 ng mL-1, respectively, in real complex samples such as cell lysates. In addition, the unique role of carbon nanotubes is also discussed by comparison with an analogue sensor assembled without the nanocarbon-based material.

11.
Aliment Pharmacol Ther ; 43(3): 364-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26582599

RESUMO

BACKGROUND: Data are scarce on the natural history of chronic hepatitis C (CHC) in patients with mild hepatitis C who did not respond to anti-viral therapy. AIM: To predict the risk of progression to cirrhosis, identifying patients with the more urgent need for therapy with effective anti-virals. METHODS: A cohort of 1289 noncirrhotic CHC patients treated with interferon-based therapy between 1990 and 2004 in two referral hospitals were followed up for a median of 12 years. RESULTS: Overall, SVR was achieved in 46.6% of patients. Data from a randomly split sample (n = 832) was used to estimate a model to predict outcomes. Among nonresponders (n = 444), cirrhosis developed in 123 (28%) patients. In this group, the 3, 5 and 10-year cumulative probabilities of cirrhosis were 4%, 7% and 22%, respectively, compared to <1% in the SVR-group (P < 0.05). Baseline factors independently associated with progression to cirrhosis in nonresponders were: fibrosis ≥F2, age >40 years, AST >100 IU/L, GGT >40 IU/L. Three logistic regression models that combined these simple variables were highly accurate in predicting the individual risk of developing cirrhosis with areas under the receiving operating characteristic curves (AUC) at 5, 7 and 10 years of ~0.80. The reproducibility of the models in the validation cohort (n = 457, nonresponders = 244), was consistently high. CONCLUSIONS: Modelling based on simple laboratory and clinical data can accurately identify the individual risk of progression to cirrhosis in nonresponder patients with chronic hepatitis C, becoming a very helpful tool to prioritise the start of oral anti-viral therapy in clinical practice.


Assuntos
Hepatite C Crônica/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/fisiopatologia , Adulto , Antivirais/uso terapêutico , Biomarcadores , Progressão da Doença , Feminino , Humanos , Interferons/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes
12.
Cell Death Differ ; 23(2): 347-57, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26206090

RESUMO

RNASET2 is a ubiquitously expressed acidic ribonuclease that has been implicated in diverse pathophysiological processes including tumorigeneis, vitiligo, asthenozoospermia, and neurodegeneration. Prior studies indicate that RNASET2 is induced in response to oxidative stress and that overexpression of RNASET2 sensitizes cells to reactive oxygen species (ROS)-induced cell death through a mechanism that is independent of catalytic activity. Herein, we report a loss-of-function genetic screen that identified RNASET2 as an essential gene for lipotoxic cell death. Haploinsufficiency of RNASET2 confers increased antioxidant capacity and generalized resistance to oxidative stress-mediated cell death in cultured cells. This function is critically dependent on catalytic activity. Furthermore, knockdown of RNASET2 in the Drosophila fat body confers increased survival in the setting of oxidative stress inducers. Together, these findings demonstrate that RNASET2 regulates antioxidant tone and is required for physiological ROS responses.


Assuntos
Apoptose , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Ribonucleases/fisiologia , Animais , Células CHO , Cricetinae , Cricetulus , Citoplasma/metabolismo , Expressão Gênica , Haploinsuficiência , Ácido Palmítico/farmacologia , RNA Nucleolar Pequeno/metabolismo , Proteínas Ribossômicas/genética
13.
Clin Lab ; 60(3): 501-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24697129

RESUMO

BACKGROUND: Storing pleural fluid samples for research purposes is a common practice, but whether adenosine deaminase (ADA), an enzyme used for the diagnosis of tuberculous pleuritis, is stable over long periods of time is unknown. METHODS: We evaluated the stability of pleural ADA concentrations in 223 samples frozen at -800C as compared to values obtained immediately following the initial thoracentesis. Sample storage time ranged from several months to slightly more than 10 years. RESULTS: ADA activity was stable for up to 2.6 years. Afterwards, it decreased 6 to 8 U/L, enough to drop 2 (3.3%) tuberculous patients below the diagnostic ADA cutoff. CONCLUSIONS: As far as ADA enzymatic activity is concerned, pleural fluid samples are viable for extended periods of time. However, some caution in interpreting results from specimens stored for > 2.6 years is prudent.


Assuntos
Adenosina Desaminase/metabolismo , Pleura/enzimologia , Humanos , Manejo de Espécimes , Tuberculose Pleural/enzimologia
14.
Arch. Soc. Esp. Oftalmol ; 87(6): 179-181, jun. 2012. ilus
Artigo em Espanhol | IBECS | ID: ibc-101476

RESUMO

Caso clínico: Mujer de 65 años que relata la aparición de una mancha blanca en el ojo izquierdo, que ha crecido en el último año. A la exploración se observa un infiltrado intraestromal blanco, con aspecto de cristales de morfología arboriforme, con una mínima respuesta inflamatoria. Se instaura tratamiento tópico sin franca mejoría, requiriendo una queratoplastia penetrante. Discusión: La queratopatía cristalina es una manifestación poco frecuente, y característica, aunque no exclusiva, de queratitis infecciosa por Streptococcus del grupo viridans. Se ha relacionado con el uso prolongado de corticoides tópicos tras queratoplastia penetrante y suele presentar mala respuesta al tratamiento médico(AU)


Case report: A 65 year-old female who consulted due to the emergence of a white spot in the eye that had grown over the last year. The physical examination showed an intrastromal white crystal-like infiltrate and a tree-like morphology, with minimal inflammatory response. It was treated topically with no clear improvement, requiring a penetrating keratoplasty. Discussion: A crystalline keratopathy is a rare event and characteristic of, but not exclusively, to a Streptococcus viridans infectious keratitis. It has been associated with prolonged use of topical steroids after penetrating keratoplasty and usually has a poor response to treatment(AU)


Assuntos
Humanos , Masculino , Feminino , Doenças da Córnea/diagnóstico , Doenças da Córnea/etiologia , Doenças da Córnea/terapia , Pterígio/complicações , Fundo de Olho , Estreptococos Viridans/isolamento & purificação , Córnea/ultraestrutura
15.
Arch Soc Esp Oftalmol ; 87(6): 179-81, 2012 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-22633609

RESUMO

CASE REPORT: A 65 year-old female who consulted due to the emergence of a white spot in the eye that had grown over the last year. The physical examination showed an intrastromal white crystal-like infiltrate and a tree-like morphology, with minimal inflammatory response. It was treated topically with no clear improvement, requiring a penetrating keratoplasty. DISCUSSION: A crystalline keratopathy is a rare event and characteristic of, but not exclusively, to a Streptococcus viridans infectious keratitis. It has been associated with prolonged use of topical steroids after penetrating keratoplasty and usually has a poor response to treatment.


Assuntos
Doenças da Córnea/etiologia , Complicações Pós-Operatórias/etiologia , Idoso , Doenças da Córnea/cirurgia , Feminino , Humanos , Ceratoplastia Penetrante , Complicações Pós-Operatórias/cirurgia , Pterígio/cirurgia
18.
Opt Express ; 20(2): 1253-60, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22274470

RESUMO

A Continuous Wave (CW) sub-THz photonic synthesis setup based on a single Passively Mode-Locked Laser Diode (PMLLD) acting as a monolithic Optical Frequency Comb Generator (OFCG) and highly selective optical filtering has been implemented to evaluate the phase noise performance of the generated sub-THz signals. The analysis of the synthesized sub-THz signals up to 120 GHz gives as a result an effective reduction of the electrical linewidth when compared to direct harmonic generation that begins at 50 GHz and becomes greater as the frequency increases. The phase noise reduction offered by the setup, along with its integration potential, cost and bandwidth, make it a promising candidate to the development of an integrated and high performance low phase noise local oscillator in the sub-THz range.


Assuntos
Lasers Semicondutores , Óptica e Fotônica/instrumentação , Óptica e Fotônica/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Artefatos , Desenho de Equipamento
19.
Rev Sci Instrum ; 81(10): 10D517, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21033872

RESUMO

A high spatial resolution two color [CO(2), λ=10.6 µm/Nd:YAG (Nd:YAG denotes neodymium-doped yttrium aluminum garnet), and λ=1.064 µm] expanded-beam multichannel heterodyne interferometer has been installed on the TJ-II stellarator. Careful design of the optical system has allowed complete control on the evolution of both Gaussian beams along the interferometer, as well as the evaluation and optimization of the spatial resolution to be expected in the measurements. Five CO(2) (measurement) channels and three Nd:YAG (vibration compensation) channels have been used to illuminate the plasma with a probe beam of 100 mm size. An optimum interpolation method has been applied to recover both interferometric phasefronts prior to mechanical vibration subtraction. The first results of the installed diagnostic are presented in this paper.

20.
Lab Anim ; 43(3): 239-42, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19237455

RESUMO

The present work determined the minimum alveolar concentrations (MAC) of halothane, isoflurane and sevoflurane in adult female gerbils (n=24). Animals were placed in a chamber for anaesthetic induction before performing tracheal intubation. The tracheal tube was connected to a non-rebreathing circuit with minimal dead space. Body temperature, blood pressure, heart and respiratory rates and end-tidal volatile anaesthetic levels were measured continuously. MAC was determined using a standard noxious stimulus (tail-clamp). All experiments were performed at the same time of the day, body temperature was maintained constant and blood-gas analysis was performed to confirm that values were within normal limits. The mean+/-SD MAC values were 1.06+/-0.11% halothane (n=8), 1.55+/-0.08% isoflurane (n=8) and 2.90+/-0.12% sevoflurane (n=7). Cardiovascular parameters at 1xMAC did not differ significantly among anaesthetics but the respiratory rate was significantly higher in the halothane group than in the isoflurane and sevoflurane groups. The SpO2 values recorded throughout anaesthesia and the pH and partial oxygen pressure values determined at the end of the study did not differ among the studied anaesthetics at 1xMAC. These data suggest that the MAC for halogenated inhalant anaesthetics in gerbils is lower than the average MAC values obtained in rats and mice.


Assuntos
Anestésicos Inalatórios/farmacocinética , Halotano/farmacocinética , Isoflurano/farmacocinética , Éteres Metílicos/farmacocinética , Alvéolos Pulmonares/metabolismo , Animais , Gasometria , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Feminino , Gerbillinae , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Intubação Intratraqueal , Respiração/efeitos dos fármacos , Sevoflurano
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