1,063 research outputs found

    Textural and structural properties of bioactive glasses in the system CaO-SiO2

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    Gel-derived CaO-SiO2 binary glasses of CaO mole fractions 0. 2, 0.3 and 0. 4 have been prepared and characterised. Pore diameter specific pore volume, skeletal density and porosity were found to increase with increasing CaO-content, whereas a concomitant decrease in specific surface area was observed. Si-29 NMR indicated that the 0.2 CaO mole fraction glass consisted of higly polymerized Q(4) and Q(3) silicate species, with some Q(2) units. With increasing CaO mole fraction, these silicate species became progressively depolymerised such that isolated SiO4 tetrahedra were detected within the 0.4 CaO glass matrix. Unusually, the glasses retained a proportion of Q(4) and Q(3) species as the CaO mole fraction was increased. All glass formulations exhibited in vitro bioactivity. The rate of hydroxyapatite precipitation followed the order 0.2 CaO > 0.4 CaO > > 0.3 CaO, an effect that is attributed to differences in the rate of dissolution of calcium from these glasses. This, in turn, appears to be dependent upon the proportion of Ca 21 participating in the formation of the glassy network

    Novel antibacterial and bioactive silicate glass nanoparticles for biomedical applications

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    In this work, the authors propose a new quick sol–gel procedure for bioglass nanoparticles production containing 10% mol of silver (AgBGs). These new AgBGs are characterized by Zeta potential analysis, scanning electron microscopy with X-ray microanalysis (SEM/EDS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and microbiological tests to confirm their bioactive and antibacterial properties. SEM shows that the average particle size is less than 200 nm and EDS confirms the successful incorporation of Ag2O in the bioglass matrix. XRD confirms the amorphous nature of the AgBGs and, after SBF immersion, reveals their bioactive behavior with the presence of crystalline phase of calcium silicate and phosphorus oxide, which are also detected by FTIR analysis. FTIR also confirms the formation of typical siloxane bonds resulting from the condensation of silicate glass. Lastly, it is found that the developed AgBGs has an antibacterial effect against two different types of bacteria, thus demonstrating their ability to reduce the bacterial infection within 16 h.The authors want to acknowledge the financial support from the Portuguese Foundation for Science and Technology through the project BioSeaGlue with the reference EXPL/CTM-BIO/0646/2013, and also the European program FEDER/COMPETE for the financial support through project LA ICVS/3Bs-2014-2015.info:eu-repo/semantics/publishedVersio

    Length and clinical effectiveness of pulmonary rehabilitation in outpatients with chronic airway obstruction

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    Study objective: To assess the clinical effectiveness of pulmonary rehabilitation (PR) after 10 or 20 consecutive sessions in outpatients with chronic airway obstruction (CAO). Design: Observational prospective cohort trial. Setting: Outpatient clinic of a rehabilitation center. Patients and interventions: Twenty-five outpatients (mean age, 65 +/- 9 years [+/- SD]; FEV1, 64 +/- 12% predicted) admitted to a comprehensive PR program, including exercise training. Measurements and results: The load reached on a cycloergometer (maximal achieved load [W-max]), the maximal and isoload dyspnea and leg fatigue on a Borg scale, 6-min walk distance (6MWD), and the health-related quality of life as assessed using the St. George's Respiratory Questionnaire (SGRQ) [total and components score] have been recorded as outcome measures at baseline, after 10 sessions (T10), and after 20 sessions (T20). The predefined criteria of the clinically significant improvement were as follows: + 15% W-max, + 54 m at 6MWD, - 1 point at isoload dyspnea and leg fatigue, and - 4% at SGRQ scores. There was a mean significant difference between changes at T20 and T10 for 6MWD (- 42.96 m; 95% confidence interval [0], - 57.79 to - 28.12 m; p = 0.001), total SGRQ (4.80; 95% CI, 2.29 to 7.31; p = 0.001), activity SGRQ (3.60; 95% CI, 0.48 to 6.71; p = 0.025), and symptoms SGRQ (5.96; 95% CI, 2.72 to 9.2; p = 0.001). The percentage of patients who improved was different at T20 as compared with T 10 for W-max (68% and 48%, respectively; p = 0.025), 6MWD (76% and 20%, p = 0.001), and total SGRQ (64% and 36%, p = 0.008). Conclusions: A 10-session course of PR provides only limited clinically significant changes of outcome measures when compared with a 20-session course in outpatients with CAO of mild-to-moderate severity

    Predictivity of clinical, laboratory and imaging findings in diagnostic definition of palpable thyroid nodules. A multicenter prospective study

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    Abstract PURPOSE: To assess the role of clinical, biochemical, and morphological parameters, as added to cytology, for improving pre-surgical diagnosis of palpable thyroid nodules. METHODS: Patients with a palpable thyroid nodule were eligible if surgical intervention was indicated after a positive or suspicious for malignancy FNAC (TIR 4-5 according to the 2007 Italian SIAPEC-IAP classification), or two inconclusive FNAC at a 653 months interval, or a negative FNAC associated with one or more risk factor. Reference standard was histological malignancy diagnosis. Likelihood ratios of malignancy, sensitivity, specificity, negative (NPV), and positive predictive value (PPV) were described. Multiple correspondence analysis (MCA) and logistic regression were applied. RESULTS: Cancer was found in 433/902 (48%) patients. Considering TIR4-5 only as positive cytology, specificity, and PPV were high (94 and 91%) but sensitivity and NPV were low (61 and 72%); conversely, including TIR3 among positive, sensitivity and NPV were higher (88 and 82%) while specificity and PPV decreased (52 and 63%). Ultrasonographic size 653\u2009cm was independently associated with benignity among TIR2 cases (OR of malignancy 0.37, 95% CI 0.18-0.78). In TIR3 cases the hard consistency of small nodules was associated with malignity (OR: 3.51, 95% CI 1.84-6.70, p\u2009<\u20090.001), while size alone, irrespective of consistency, was not diagnostically informative. No other significant association was found in TIR2 and TIR3. CONCLUSIONS: The combination of cytology with clinical and ultrasonographic parameters may improve diagnostic definition of palpable thyroid nodules. However, the need for innovative diagnostic tools is still high

    Taste intensity and hedonic responses to simple beverages in gastrointestinal cancer patients

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    Changes in the taste of food have been implicated as a potential cause of reduced dietary intake among cancer patients. However, data on intensity and hedonic responses to the four basic tastes in cancer are scanty and contradictory. The present study aimed at evaluating taste intensity and hedonic responses to simple beverages in 47 anorectic patients affected by gastrointestinal cancer and in 55 healthy subjects. Five suprathreshold concentrations of each of the four test substances (sucrose in black current drinks, citric acid in lemonade, NaCl in unsalted tomato juice, and urea in tonic water) were used. Patients were invited to express a judgment of intensity and pleasantness ranging from 0 to 10. Mean intensity scores directly correlated with concentrations of sour, salty, bitter, and sweet stimuli, in both normals and those with cancer. Intensity judgments were higher in cancer patients with respect to sweet (for median and high concentrations, P < 0.05), salty (for all concentrations, P < 0.05), and bitter tastes (for median concentration, P < 0.01). Hedonic function increased with the increase of the stimuli only for the sweet taste. A negative linear correlation was found between sour, bitter, and salty concentrations and hedonic score. Both in cancer patients and in healthy subjects, hedonic judgments increased with the increase of the stimulus for the sweet taste (r 1/4 0.978 and r 1/4 0.985, P 1/4 0.004 and P 1/4 0.002, respectively), and decreased for the salty (r 1/4 ??0.827 and r 1/4 ??0.884, P 1/4 0.084 and P 1/4 0.047, respectively) and bitter tastes (r 1/4 ??0.990 and r 1/4 ??0.962, P 1/4 0.009 and P 1/4 0.001, respectively). For the sour taste, the hedonic scores remained stable with the increase of the stimulus in noncancer controls (r 1/4 ??0.785, P 1/4 0.115) and decreased in cancer patients (r 1/4 ??0.996, P 1/4 0.0001). The hedonic scores for the sweet taste and the bitter taste were similar in cancer patients and healthy subjects, and these scores were significantly higher in cancer patients than in healthy subjects for most of the concentrations of the salty taste and all the concentrations of the sour taste. The present study suggests that cancer patients, compared to healthy individuals, have a normal sensitivity, a normal likingfor pleasant stimuli, and a decreased dislike for unpleasant stimuli. Moreover, when compared to controls, they show higher hedonic scores for middle and high concentrations of the salty taste and for all concentrations of the sour taste. Further studies are needed to evaluate whether these changes observed in cancer patients translate into any alteration in dietary behavior and/or food preferences

    Malignancy risk analysis in patients with inadequate fine needle aspiration cytology (FNAC) of the thyroid

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    Background Thyroid fine needle aspiration cytology (FNAC) is the standard diagnostic modality for thyroid nodules. However, it has limitations among which is the incidence of non-diagnostic results (Thy1). Management of cases with repeatedly non-diagnostic FNAC ranges from simple observation to surgical intervention. We aim to evaluate the incidence of malignancy in non-diagnostic FNAC, and the success rate of repeated FNAC. We also aim to evaluate risk factors for malignancy in patients with non-diagnostic FNAC. Materials and Methods Retrospective analyses of consecutive cases with thyroid non diagnostic FNAC results were included. Results Out of total 1657 thyroid FNAC done during the study period, there were 264 (15.9%) non-diagnostic FNAC on the first attempt. On repeating those, the rate of a non-diagnostic result on second FNAC was 61.8% and on third FNAC was 47.2%. The overall malignancy rate in Thy1 FNAC was 4.5% (42% papillary, 42% follicular and 8% anaplastic), and the yield of malignancy decreased considerably with successive non-diagnostic FNAC. Ultrasound guidance by an experienced head neck radiologist produced the lowest non-diagnostic rate (38%) on repetition compared to US guidance by a generalist radiologist (65%) and by non US guidance (90%). Conclusions There is a low risk of malignancy in patients with a non-diagnostic FNAC result, commensurate to the risk of any nodule. The yield of malignancy decreased considerably with successive non-diagnostic FNAC

    Systematic review of cure and recurrence rates following minimally invasive parathyroidectomy

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    Background The majority of patients with primary hyperparathyroidism (PHPT) have a single overactive adenoma. Advances in preoperative imaging and surgical adjuncts have given rise to minimally invasive parathyroidectomy (MIP), with lower complication rates in comparison with bilateral neck exploration. Misdiagnosis and undertreatment of multiglandular disease, leading to potentially higher recurrence rates, remains a concern. This study evaluated risks of long‐term (1 year or more) recurrence following ‘targeted’ MIP in PHPT. Methods Multiple databases were searched for studies published between January 2004 and March 2017, looking at long‐term outcomes (1 year or more) following targeted MIP for PHPT. English‐language studies, with at least 50 patients and a mean follow‐up of 1 year, were included. Results A total of 5282 patients from 14 studies were included. Overall mean recurrence and cure rates were 1·6 (range 0–3·5) and 96·9 (95·5–100) per cent respectively. Mean follow‐up was 33·5 (1–145) months. When intraoperative parathyroid hormone (PTH) measurements were not done, cure rates were higher (99·3 per cent versus 98·1 per cent with use of intraoperative PTH measurement; P < 0·001) and recurrence rates lower (0·2 versus 1·5 per cent respectively; P < 0·001). Conclusion Targeted MIP for a presumed single overactive adenoma was associated with very low recurrence rates, without the need for intraoperative PTH measurement when preoperative imaging studies were concordant. Targeted MIP should be encouraged

    La « conception mystique de l’hégélianisme » d’Augusto Vera

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    Cet article reconstruit la position de Vera au sujet de la pensée de Hegel, dans son évolution et dans sa forme finale. Connu en tant que traducteur, Vera en est aussi un interprète reconnu dans toute l’Europe. Son évolution du scepticisme à une philosophie systématique, hégélienne et orthodoxe, se fait en stricte relation avec les options de la philosophie française. En effet, l’hégélianisme de Vera ne se comprend qu’en relation avec la pensée de Cousin, qu’il veut radicaliser, en particulier en donnant une interprétation « platonicienne » et « rationaliste » de la dialectique.This article reconstructs Vera’s position around Hegel’s thought, in its evolution and in its final form. Known as a translator, Vera is also a recognized interpreter throughout Europe. Its evolution from skepticism to a systematic, Hegelian and orthodox philosophy is made in strict relation with the options of French philosophy. Indeed, Vera’s Hegelianism can only be understood in relation to Cousin’s thought, which he wants to radicalize, in particular by giving a “Platonic” and “rationalist” interpretation of the dialectic

    Relatório de atividade clínica

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    A Medicina Dentária está em constante evolução, com o intuito de utilizar sempre novos materiais e novas técnicas para melhorar o resultado final e ter prognósticos cada vez mais previsíveis. Na última década, a elevada exigência estética por parte dos pacientes nos tratamentos dentários, fez com que os Médicos Dentistas melhorassem as técnicas e a pesquisa de materiais sempre mais estéticos, nunca esquecendo a importância do complexo mastigatório. De salientar a incrível evolução da Medicina Dentária com o advento de máquinas e sistemas tecnológicos mais inovadores, por exemplo a CBCT (cone beam computer tomography), ou o scanner intraoral ou o DSD (Dental Smile Design), obtendo assim uma simulação digital do resultado final. Este relatório de atividade clínica realiza uma análise qualitativa e quantitativa dos atos clínicos realizados como assistente e como operador, durante o último ano letivo do curso de Mestrado Integrado em Medicina Dentária na Clínica Universitária da Universidade Católica Portuguesa de Viseu. A presente dissertação é dividida em 3 seções: a primeira parte, é uma introdução à medicina dentária, tratada de uma forma geral; na segunda parte, é realizada uma análise epidemiológica dos pacientes atendidos na Clínica Universitária da Universidade Católica Portuguesa de Viseu e, por fim, são apresentados três casos clínicos, investigando mais especificamente as técnicas de diagnóstico, tratamento e prognóstico, envolvidos na resolução de cada um deles.Dental Medicine is constantly evolving with the aim of always using new materials and new techniques to improve the final result and have increasingly predictable prognoses. In the last decade, the high aesthetic requirement on the part of the patients in the dental treatments, made that the dentists improved the techniques and the research of materials always more aesthetic, never forgetting the importance of the masticatory complex. Of note is the incredible evolution of dental medicine with the advent of more innovative machines and technological systems, for example cone beam computer tomography (CBCT), or intraoral scanner or Dental Smile Design (DSD), thus obtaining a digital simulation of the result Last. This clinical activity report performs a qualitative and quantitative analysis of the clinical acts performed both as assistant and operator during the last academic year of the Integrated Master in Dental Medicine course at the University Clinic of the Portuguese Catholic University of Viseu. The present dissertation is divided in 3 sections: the first part, is an introduction to dentistry, treated in a general way; in the second part is faced an epidemiological analysis of the patients treated at the University Clinic of the Portuguese Catholic University of Viseu. Finally, in the third part are presented three clinical, focusing on the diagnostic, treatment and prognostic techniques involved in the resolution of each case
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