168 research outputs found
Cell adhesion and proliferation of skeletal muscle cells on piezoelectric poly(vinylidene fluoride) membranes
Several body tissues, including bone and muscle, are subjected to electromechanical solicitations during their functional activity [1-3]. Thus, the use of electroactive polymers as active scaffolds shows innovative large potential for tissue engineering applications as it offers functional resemblance to biological clues [2]. In particular, piezoelectric polymers have shown suitability for tissue engineering due to their ability to vary surface charge when a mechanical load is applied [4] and their possibility to be processed in form of films, porous 2D and 3D membranes and scaffolds and fiber mats.
The influence of poling state and morphology (film or fiber morphology) of
piezoelectric poly(vinylidene fluoride) (PVDF) on the adhesion and morphology of
myoblast cells was studied. Non-poled, ‘‘poled +’’ and “poled-’’ !-PVDF films were prepared by solvent casting followed by corona poling. Further, random and aligned electrospun !-PVDF fiber mats were also prepared. It is demonstrated that negatively charged surfaces improve cell adhesion and proliferation and that the directional growth of the myoblast cells can be achieved by culturing the cell on aligned fibers.
Therefore, the potential application of electroative materials for muscle regeneration is demonstrated
Detection of human papillomavirus in laryngeal squamous cell carcinoma: systematic review and meta-analysis
Background: Recent studies have reported a human papillomavirus (HPV) prevalence of 20% to 30% in laryngeal squamous cell carcinoma (LSCC), although clinical data on HPV involvement remain largely inconsistent, ascribed by some to differences in HPV detection methods or in geographic origin of the studies.
Objective
To perform a systematic review and formal meta-analysis of the literature reporting on HPV detection in LSCC.
Methods
Literature was searched from January 1964 until March 2015. The effect size was calculated as event rates (95% confidence interval [CI]), with homogeneity testing using Cochran's Q and I2 statistics. Meta-regression was used to test the impact of study-level covariates (HPV detection method, geographic origin) on effect size. Potential publication bias was estimated using funnel plot symmetry.
Results
One hundred seventy nine studies were eligible, comprising a sample size of 7,347 LSCCs from different geographic regions. Altogether, 1,830 (25%) cases tested HPV-positive considering all methods, with effect size of 0.269 (95% CI: 0.242 to 0.297; random-effects model). In meta-analysis stratified by the 1) HPV detection technique and 2) geographic study origin, the between-study heterogeneity was significant only for geographic origin (P = .0001). In meta-regression, the HPV detection method (P = .876) or geographic origin (P = .234) were not significant study-level covariates. Some evidence for publication bias was found only for studies from North America and those using non–polymerase chain reaction methods, with a marginal effect on adjusted point estimates for both.
Conclusions
Variability in HPV detection rates in LSCC is explained by geographic origin of study but not by HPV detection method. However, they were not significant study-level covariates in formal meta-regression
Enhanced proliferation of pre-osteoblastic cells by dynamic piezoelectric stimulation
[EN] This work reports on the influence of the polarization of electroactive poly(vinylidene fluoride), PVDF, on the biological response of cells cultivated under static and dynamic conditions. Non-poled and "poled +" beta-PVDF with and without a titanium layer were thus prepared. A thin titanium layer was deposited on PVDF films in order to obtain a more homogeneous surface charge. The MC3T3-E1 osteoblast cell culture exhibited different responses in the presence of PVDF films. The positively charged beta-PVDF films promote higher osteoblast adhesion and proliferation, which is higher under dynamic conditions on poled samples, showing that the surface charge under mechanical stimulation improves the osteoblast growth. Therefore, electroactive membranes and scaffolds can provide the necessary electrical stimuli for the growth and proliferation of specific cells.JLGR acknowledge the support of the Spanish Ministry of Education through project No. MAT2010-21611-C03-01 (including the FEDER financial support) and project EUI2008-00126.Ribeiro, C.; Moreira, S.; Correia, V.; Sencadas, V.; Rocha, JG.; Gama, FM.; Gómez Ribelles, JL.... (2012). Enhanced proliferation of pre-osteoblastic cells by dynamic piezoelectric stimulation. RSC Advances. 2(30):11504-11509. https://doi.org/10.1039/c2ra21841k115041150923
A platform with combined environmental and physiological wireless data acquisition for AAL applications
http://isami2010.di.uminho.pt/Ambient Assisted Living is based on a set of technologies with the aim to provide an enhanced support to people’s daily life. One important field deals with the offer of new solutions for healthcare. Those solutions intend to improve the population quality of life and reduce costs associated with healthcare. Before that happens, new platforms, hardware and software, must be available in order to acquire and store the required signals, to process and extract information from those signals, and to detect a set of features required to fire alarms and/or electronic assistance. This paper presents a platform (hardware and software) that was designed to acquire data from a subject, or from a device, and send it to a remote hub. It was designed taking into account its size, power autonomy, and quality of sfor one day
Percutaneous Ventricular Restoration (PVR) Therapy Using the Parachute Device in 100 Subjects with Ischaemic Dilated Heart Failure: One-Year Primary Endpoint Results of PARACHUTE III, a European Trial
AIMS:
This prospective, non-randomised, observational study conducted in Europe was designed in order to assess the long-term safety and efficacy of the Parachute device in ischaemic heart failure subjects as a result of left ventricle remodelling after anterior wall myocardial infarction.
METHODS AND RESULTS:
One hundred subjects with New York Heart Association Class II-IV ischaemic heart failure (HF), ejection fraction (EF) between 15% and 40%, and dilated akinetic or dyskinetic anterior-apical wall without the need to be revascularised were enrolled. The primary safety endpoint was procedural- or device-related major adverse cardiac cerebral events (MACCE). The secondary safety endpoint was the composite of mortality and morbidity. Secondary efficacy endpoints included haemodynamic measurements determined by echocardiography, LV volume indices, and assessment of functional improvement measured by a standardised six-minute walk test. Of the 100 subjects enrolled, device implantation was successful in 97 (97%) subjects. The one-year rates of the primary and secondary safety endpoints were 7% and 32.3%, respectively. The secondary endpoints, LV volume reduction (p<0.0001) and six-minute walk distance improvement (p<0.01), were achieved.
CONCLUSIONS:
The favourable outcomes observed in this high-risk population provide reassuring safety and efficacy data to support adoption of this technology as a therapeutic option for HF subjects.info:eu-repo/semantics/publishedVersio
Adaptabilidade e estabilidade de cultivares de milho na zona agreste do nordeste brasileiro.
Realizou-se este trabalho visando conhecer a adaptabilidade e a estabilidade de diversas cultivares de milho quando submetidas a distintas condições ambientais do agreste nordestino
Desempenho de hÃbridos de milho no Piauà e Maranhão: safra 2004-2005.
Na safra 2004/2005, 35 hÃbridos de milho foram submetidos a nove ambientes do Meio-Norte brasileiro, visando conhecer a adaptabilidade e a estabilidade para fins de recomendação. Utilizou-se o delineamento experimental em blocos ao acaso com três repetições. Constataram-se, na análise de variância conjunta, diferenças entre os hÃbridos e os ambientes e um comportamento inconsistente desses ante as variações ambientais, no tocante aos caracteres alturas de planta e de espigas, estande de colheita, espigas colhidas e rendimento de grãos. Os municÃpios de Teresina e Baixa Grande do Ribeiro,PI, mostraram-se mais propÃcios ao cultivo do milho. Os hÃbridos que apresentaram rendimentos médios de grãos acima da média geral (5.230 kg ha-1), expressaram melhor adaptação. Os hÃbridos 2 B 710 e Strike, por serem exigentes nas condições desfavoráveis e responderem à melhoria ambiental, destacaram-se para os ambientes favoráveis. Os hÃbridos que evidenciam adaptabilidade ampla, a exemplo dos 2 B 619, Pioneer 30 F 70, Pioneer 30 F 44, DAS 8420, DAS 8480, dentre outros, consubstanciam-se em alternativas importantes para a agricultura regional.bitstream/CPAMN-2009-09/21228/1/BOLP62.pd
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