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1.
Nat Prod Res ; : 1-8, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742440

RESUMO

Doryopteris raddiana (Presl) Fée, a traditional contraceptive in Mbya culture, lacks scientific scrutiny regarding its chemical composition and contraceptive efficacy. Employing X-ray fluorescence, Fourier-transform infrared spectroscopy, and thermal analysis, we explored the plant's organs. Multielemental analysis excluded toxic elements. Key phytoconstituents identified by gas chromatography-mass spectrometry in the extracts obtained through infusion were glycerine, 1,3-dimethyl propane, and catechol in leaves; glycerine, cis-13-octadecenoic acid methyl ester, and 2-deoxy-D-erythro-pentose in stems and roots. Among these chemicals, glycerine emerged as the sole constituent with contraceptive potential, particularly intravaginally. Extract activity tests conducted on ram spermatozoa exhibited a reduction in the percentage of rapid spermatozoa but no significant impact on total motility, progressive motility, or viability. The reported data would only weakly support the advocated contraceptive action of this fern upon vaginal application, not through the oral administration of its decoction.

2.
Eur Heart J Cardiovasc Imaging ; 25(6): 727-734, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38635738

RESUMO

AIMS: The European Association of Cardiovascular Imaging (EACVI) Scientific Initiatives Committee performed a global survey on radiation exposure in interventional echocardiography. The survey aimed to collect data on local practices for radioprotection in interventional echocardiography and to assess the awareness of echocardiography operators about radiation-related risks. METHODS AND RESULTS: A total of 258 interventional echocardiographers from 52 different countries (48% European) responded to the survey. One hundred twenty-two (47%) participants were women. Two-thirds (76%) of interventional echocardiographers worked in tertiary care/university hospitals. Interventional echocardiography was the main clinical activity for 34% of the survey participants. The median time spent in the cath-lab for the echocardiographic monitoring of structural heart procedures was 10 (5-20) hours/month. Despite this, only 28% of interventional echocardiographers received periodic training and certification in radioprotection and 72% of them did not know their annual radiation dose. The main adopted personal protection devices were lead aprons and thyroid collars (95% and 92% of use, respectively). Dedicated architectural protective shielding was not available for 33% of interventional echocardiographers. Nearly two-thirds of responders thought that the radiation exposure of interventional echocardiographers was higher than that of interventional cardiologists and 72% claimed for an improvement in the radioprotection measures. CONCLUSION: Radioprotection measures for interventional echocardiographers are widely variable across centres. Radioprotection devices are often underused by interventional echocardiographers, portending an increased radiation-related risk. International scientific societies working in the field should collaborate to endorse radioprotection training, promote reliable radiation dose assessment, and support the adoption of radioprotection shielding dedicated to interventional echocardiographers.


Assuntos
Ecocardiografia , Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Feminino , Exposição Ocupacional/prevenção & controle , Exposição à Radiação/prevenção & controle , Masculino , Europa (Continente) , Inquéritos e Questionários , Doses de Radiação , Adulto , Pessoa de Meia-Idade , Ultrassonografia de Intervenção
4.
Sci Total Environ ; 861: 160534, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36574545

RESUMO

The escape behaviour, measured as flight initiation distance (FID; the distance at which individuals take flight when approached by a potential predator, usually a human in the study systems), is a measure widely used to study fearfulness and risk-taking in animals. Previous studies have shown significant differences in the escape behaviour of birds inhabiting cemeteries and urban parks in European cities, where birds seem to be shyer in the latter. We collected a regional dataset of the FID of birds inhabiting cemeteries and parks across Latin America in peri-urban, suburban and urban parks and cemeteries. FIDs were recorded for eighty-one bird species. Mean species-specific FIDs ranged from 1.9 to 19.7 m for species with at least two observations (fifty-seven species). Using Bayesian regression modelling and controlling for the phylogenetic relatedness of the FID among bird species and city and country, we found that, in contrast to a recent publication from Europe, birds escape earlier in cemeteries than parks in the studied Latin American cities. FIDs were also significantly shorter in urban areas than in peri-urban areas and in areas with higher human density. Our results indicate that some idiosyncratic patterns in animal fearfulness towards humans may emerge among different geographic regions, highlighting difficulties with scaling up and application of regional findings to other ecosystems and world regions. Such differences could be associated with intrinsic differences between the pool of bird species from temperate European and mostly tropical Latin American cities, characterized by different evolutionary histories, but also with differences in the historical process of urbanization.


Assuntos
Cemitérios , Ecossistema , Animais , Humanos , América Latina , Filogenia , Parques Recreativos , Teorema de Bayes , Aves , Cidades , Europa (Continente)
5.
BMC Health Serv Res ; 22(1): 761, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689219

RESUMO

BACKGROUND: Informing about permanent deferral requires a process that links the notifier with the donor in a particular way. Little is known about the type of information and how it is disclosed to the donors. The current study aimed to examine perceptions and practices of notifier and blood donor within the framework of the notification process of permanent deferral and from the perspective of the notifier-blood donor relationship. METHODS: A qualitative study with in-depth interviews. The participants were 13 notifiers and 25 permanently deferred donors. Participants were recruited from a national blood bank and a state's blood bank. The entire dataset/narratives were analysed using the method of thematic analysis. RESULTS: The disclosure of permanent deferral was understood as a matter of disclosing the serological test results and their medical meaning along with a concise explanation of the deferral status with regard to future blood donation and the plan to be followed. The notifiers preferred to act in accordance with the standard protocol despite acknowledging the adverse psychological and social effects to which donors are exposed when they are informed of the possible disease and the consequent permanent deferral. Donors described a variety of psychological and social affectations. They valued honesty in the communication, the clarity of the information provided and a greater involvement of the notifier. CONCLUSION: Even though the notification process does not imply that medical care is being offered to donors, the notifier is the administrator of the well-being of the donor. Notification must not be considered as something apart from care, since it is intimately related to the health of each of the donors and their medical care.


Assuntos
Bancos de Sangue , Doadores de Sangue , Humanos , México , Pesquisa Qualitativa
6.
Neth Heart J ; 30(4): 212-226, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33052577

RESUMO

BACKGROUND: The integration of computed tomography (CT)-derived left ventricular outflow tract area into the echocardiography-derived continuity equation results in the reclassification of a significant proportion of patients with severe aortic stenosis (AS) into moderate AS based on aortic valve area indexed to body surface area determined by fusion imaging (fusion AVAi). The aim of this study was to evaluate AS severity by a fusion imaging technique in patients with low-gradient AS and to compare the clinical impact of reclassified moderate AS versus severe AS. METHODS: We included 359 consecutive patients who underwent transcatheter aortic valve implantation for low-gradient, severe AS at two academic institutions and created a joint database. The primary endpoint was a composite of all-cause mortality and rehospitalisations for heart failure at 1 year. RESULTS: Overall, 35% of the population (n = 126) were reclassified to moderate AS [median fusion AVAi 0.70 (interquartile range, IQR 0.65-0.80) cm2/m2] and severe AS was retained as the classification in 65% [median fusion AVAi 0.49 (IQR 0.43-0.54) cm2/m2]. Lower body mass index, higher logistic EuroSCORE and larger aortic dimensions characterised patients reclassified to moderate AS. Overall, 57% of patients had a left ventricular ejection fraction (LVEF) <50%. Clinical outcome was similar in patients with reclassified moderate or severe AS. Among patients reclassified to moderate AS, non-cardiac mortality was higher in those with LVEF <50% than in those with LVEF ≥50% (log-rank p = 0.029). CONCLUSIONS: The integration of CT and transthoracic echocardiography to obtain fusion AVAi led to the reclassification of one third of patients with low-gradient AS to moderate AS. Reclassification did not affect clinical outcome, although patients reclassified to moderate AS with a LVEF <50% had worse outcomes owing to excess non-cardiac mortality.

7.
J Invasive Cardiol ; 33(12): E1004, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34866052

RESUMO

High rates of spontaneous rupture and death have been described when the pseudoaneurysm is left untreated. Percutaneous closure has emerged as an alternative to surgery in patients with unacceptable surgical risk. In this case, transthoracic echocardiography allowed optimal characterization of the defect and successful procedure guidance, avoiding risks derived from more invasive intraprocedural imaging techniques.


Assuntos
Dispositivo para Oclusão Septal , Ecocardiografia , Humanos , Doença Iatrogênica , Dispositivo para Oclusão Septal/efeitos adversos
8.
J Intern Med ; 290(3): 715-727, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34114700

RESUMO

BACKGROUND: The pathophysiological mechanisms linking tricuspid regurgitation (TR) and chronic kidney disease (CKD) remain unknown. This study aimed to determine which pathophysiological mechanisms related to TR are independently associated with renal dysfunction and to evaluate the impact of renal impairment on long-term prognosis in patients with significant (≥ moderate) secondary TR. METHODS: A total of 1234 individuals (72 [IQR 63-78] years, 50% male) with significant secondary TR were followed up for the occurrence of all-cause mortality and the presence of significant renal impairment (eGFR of <60 mL min-1  1.73 m-2 ) at the time of baseline echocardiography. RESULTS: Multivariable analysis demonstrated that severe right ventricular (RV) dysfunction (TAPSE < 14 mm) was independently associated with the presence of significant renal impairment (OR 1.49, 95% CI 1.11 to 1.99, P = 0.008). Worse renal function was associated with a significant reduction in survival at 1 and 5 years (85% vs. 87% vs. 68% vs. 58% at 1 year, and 72% vs. 64% vs. 39% vs. 19% at 5 years, for stage 1, 2, 3 and 4-5 CKD groups, respectively, P < 0.001). The presence of severe RV dysfunction was associated with reduced overall survival in stage 1-3 CKD groups, but not in stage 4-5 CKD groups. CONCLUSIONS: Of the pathophysiological mechanisms identified by echocardiography that are associated with significant secondary TR, only severe RV dysfunction was independently associated with the presence of significant renal impairment. In addition, worse renal function according to CKD group was associated with a significant reduction in survival.


Assuntos
Insuficiência Renal Crônica , Insuficiência da Valva Tricúspide , Disfunção Ventricular Direita , Idoso , Feminino , Humanos , Rim/diagnóstico por imagem , Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Insuficiência Renal Crônica/complicações , Estudos Retrospectivos , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia
12.
Alcohol Alcohol ; 55(2): 157-163, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-31897468

RESUMO

AIMS: Platelet-derived growth factor (PDGF) promotes liver collagen deposition, acting on hepatic stellate cells. Despite this, low serum PDGF levels were reported in chronic hepatitis C or B infection, although some studies yield the opposite result. Since PDGF may be related not only to fibrosis but also with vascular, neuronal or muscle disease, it is important to analyze its behavior in alcoholics. METHODS: In total, 17 controls and 62 alcoholic patients consecutively admitted to the hospitalization unit of the Internal Medicine Service were included. We determined serum levels of PDGF C, routine laboratory evaluation, tumor necrosis factor-α, interleukin (IL)-6 and IL-8 and malondialdehyde (MDA) levels. We analyzed the relationships between PDGF and liver function, ethanol intake and inflammatory reaction by both univariate and multivariate analysis to discern which variables PDGF levels depend on. RESULTS: Serum PDGF levels were significantly lower among patients (675 ± 466 pg/ml) than among controls (1074 ± 337 pg/ml; Z = 3.70; P < 0.001), and even lower among cirrhotics (549 ± 412 among cirrhotics vs 778 ± 487 among non-cirrhotics; Z = 2.33; P = 0.02). PDGF levels showed a direct correlation with prothrombin activity (ρ = 0.50; P < 0.001), platelet count (ρ = 0.44; P < 0.001) and inverse ones with bilirubin (ρ = -0.39; P = 0.002), IL-6 (ρ = -0.33; P = 0.016), IL-8 (ρ = -0.47; P < 0.001), and MDA levels (ρ = -0.44; P < 0.001). By multivariate analysis, only prothrombin activity and platelet count were independently related to PDGF. CONCLUSION: PDGF-C levels are decreased in alcoholics, especially among cirrhotics. Multivariate analysis discloses that only prothrombin activity and platelet count are independently related to PDGF-C levels.


Assuntos
Alcoolismo/sangue , Linfocinas/sangue , Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/complicações , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Cirrose Hepática Alcoólica/sangue , Cirrose Hepática Alcoólica/complicações , Testes de Função Hepática , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas , Fator de Necrose Tumoral alfa/sangue
13.
Nanomaterials (Basel) ; 9(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491904

RESUMO

Chronic kidney disease (CKD) is a worldwide public health problem. In stages III and IV of CKD, uremic toxins must be removed from the patient by absorption, through a treatment commonly called hemodialysis. Aiming to improve the absorption of uremic toxins, we have studied its absorption in chemically modified graphene nanoplatelets (GNPs). This study involved the reaction between GNPs and diamines with reaction times of 30, 45 and 60 min using ultrasound waves of different amplitudes and frequencies. Functionalized GNPs were analyzed by Fourier Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy and energy dispersitive spectroscopy (SEM-EDS), and Thermogravimetric analysis (TGA). The analysis of the functional groups confirmed the presence of amide and hydroxyl groups on the surface of the GNPs by reactions of diamines with carboxylic acids and epoxides. Adsorption of uremic toxins was determined using equilibrium isotherms, where the maximum percentage of removal of uremic toxins was 97%. Dispersion of modified graphene nanoplatelets was evaluated in water, ethanol and hexane, as a result of this treatment was achieved a good and effective dispersion of diamines-modified graphene nanoplatelets in ethanol and hexane. Finally, the results of hemolysis assays of the modified graphene with amine demonstrated that it was not cytotoxic when using 500 mg/mL. The samples of modified graphene demonstrated low degree of hemolysis (<2%), so this material can be used for in vivo applications such as hemodialysis.

14.
Polymers (Basel) ; 11(7)2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31330943

RESUMO

The study of polymeric nanocomposites is a possible alternative to conventional flame retardants. The aim of the present work is to investigate the effects of carbon-nanotubes (CNT) and TiO2 nanoparticles (NPs) on the thermo-mechanical, flammability, and electrical properties of polypropylene (PP). In this work, PP-TiO2/CNT nanocomposites were obtained with TiO2/CNT mixtures (ratio 1:2) through the melt extrusion process, with different weight percentage of nanoparticles (1, 5, and 10 wt %). The PP-TiO2/CNT nanocomposites were characterized by DSC, TGA, MFI, FTIR, XRD, and SEM. It was possible to determine that the thermal stability of the PP increases when increasing the content of NPs. A contrary situation is observed in the degree of crystallinity and thermo-oxidative degradation, which decreased with respect to pure PP. The TiO2 NPs undergo coalition and increase their size at a lower viscosity of the nanocomposite (1 and 5 wt %). The mechanical properties decreased slightly, however, the Young's modulus presented an improvement of 10% as well as electrical conductivity, this behavior was noted in nanocomposites of 10 wt % of NPs. Flammability properties were measured with a cone calorimeter, and a reduction in the peak heat release rate was observed in nanocomposites with contents of nanoparticles of 5 and 10 wt.

15.
Neth Heart J ; 27(5): 231-232, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30949971
16.
Materials (Basel) ; 12(5)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823647

RESUMO

Ultrasound energy is a green and economically viable alternative to conventional techniques for surface modification of materials. The main benefits of this technique are the decrease of processing time and the amount of energy used. In this work, graphene nanoplatelets were treated with organic acids under ultrasonic radiation of 350 W at different times (30 and 60 min) aiming to modify their surface with functional acid groups and to improve the adsorption of uremic toxins. The modified graphene nanoplatelets were characterized by Fourier transform infrared spectroscopy (FT⁻IR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The optimum time for modification with organic acids was 30 min. The modified nanoplatelets were tested as adsorbent material for uremic toxins using the equilibrium isotherms where the adsorption isotherm of urea was adjusted for the Langmuir model. From the solution, 75% of uremic toxins were removed and absorbed by the modified nanoplatelets.

19.
Sci Rep ; 8(1): 10940, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30026577

RESUMO

Embedded solitons are rare self-localized nonlinear structures that, counterintuitively, survive inside a continuous background of resonant states. While this topic has been widely studied in nonlinear optics, it has received almost no attention in the field of Bose-Einstein condensation. In this work, we consider experimentally realizable Bose-Einstein condensates loaded in one-dimensional optical lattices and demonstrate that they support continuous families of stable three-dimensional (3D) embedded solitons. These solitons can exist inside the resonant continuous Bloch bands because they are protected by symmetry. The analysis of the Bogoliubov excitation spectrum as well as the long-term evolution after random perturbations proves the robustness of these nonlinear structures against any weak perturbation. This may open up a way for the experimental realization of stable 3D matter-wave embedded solitons as well as for monitoring the gap-soliton to embedded-soliton transition.

20.
Neth Heart J ; 25(6): 394-400, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28444570

RESUMO

PURPOSE: Data on MitraClip procedural safety and efficacy in the Netherlands are scarce. We aim to provide an overview of the Dutch MitraClip experience. METHODS: We pooled anonymised demographic and procedural data of 1151 consecutive MitraClip patients, from 13 Dutch hospitals. Data was collected by product specialists in collaboration with local operators. Effect on mitral regurgitation was intra-procedurally assessed by transoesophageal echocardiography. Technical success and device success were defined according to modified definitions of the Mitral Valve Academic Research Consortium (MVARC). RESULTS: Median age was 76 (interquartile range 69-82) years and 59% were males. Patients presented with ≥moderate mitral regurgitation and a predominance of functional mitral regurgitation (72%). Overall, 611 (53%) patients were treated with one Clip, 486 (42%) with ≥2 Clips and 54 (5%) received no Clip. The number of patients with ≥2 Clips increased from 22% in 2009 to 52% in 2016. Device success and technical success were 91 and 95%, respectively, and were consistent over the years. Significant reduction of mitral regurgitation by MitraClip was achieved in 94% of patients and was observed more often in patients with functional mitral regurgitation (95% vs. 91%, p = 0.025). Device time declined from 145 min in 2009 to 55 min in 2016. CONCLUSION: MitraClip experience in the Netherlands is growing with excellent technical success and device success. Over the years, device time decreased and more patients were treated with ≥2 Clips.

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