O xilitol na prevenção da cárie dentária

O papel dos substitutos do açúcar na composição dos alimentos ingeridos entre as principais refeições é reconhecido como importante na prevenção da cárie dentária. Este artigo apresenta uma revisão de estudos que utilizaram o xilitol como substituto do açúcar. O xilitol, um poliálcool com 5 atomos de carbono e que possui 90% a 100% da capacidade adoçante da sacarose, apresenta diversas propriedades que permitem a sua classificaço como não cariogénico. Da análise dos artigos estudados conclui-se que o xilftol possui caraderisticas que permitem a sua utilização na prevenção da cárie dentária.The role of sugar alcohols on the composition of snacks is of major importante as an element In the prevention of tooth decay. T1JiS article presents a review of studies where xylitol was the chosen sugar substitute. Xylitol is a 5 carbon polyalcohol with 90% to a 100% ol’ sucrose’s swedness capacity and it has properties that allow its classification as non-cariogenic. From the analysis of several studies xylitol is considered to have characteristia that makes possible its utilization for prevention of tooth decay.info:eu-repo/semantics/publishedVersio

Texture analysis can be used to improve skin sonography quantification capacities

Image interpretation of sonograms is a difficult process since it largely depends on the observer’s experience and is the limited by image resolution of commercial scanners. Texture analysis offers a range of analysis tools that assess the spatial variation and distribution of gray levels within a given image and translates them into quantitative parameters. We compared non-treated skin, hydrated, and erythema. Texture analysis parameters (entropy, contrast, correlation, energy, homogeneity) were calculated from the epidermis, dermis, and hypodermis selected regions of interest. Entropy, contrast and homogeneity were higher in the more echogenic epidermis, while correlation and energy were higher for the more homogenous dermis. The echo, entropy, contrast and correlation were found to be consistently lower on both layers of the hydrated skin and erythema, while energy was higher. These results suggest that texture analysis is useful to quantitatively describe the differences in skin layers based on their echogenic profile

The effects of spinal anaesthesia for elective caesarean section on uterine and umbilical arterial pulsatility indexes in normotensive and chronic hypertensive pregnant women: a prospective, longitudinal study

Background: Despite the known effects of neuraxial blockade on major vessel function and the rapid decrease in uterine vascular impedance, it is unclear how the blockade affects the utero-placental circulation in the near-term. We hypothesize that among women with chronic hypertension, a loss of sympathetic tonus consequent to spinal block may cause significant changes in the utero-placental haemodynamics than the changes typical in normal pregnant women. Therefore, the main study objective was to analyse the effect of spinal anaesthesia for caesarean section on uterine and umbilical arterial impedance in pregnant women at term diagnosed with stage-1 chronic hypertension. Methods: A prospective, longitudinal study was performed in singleton pregnant women (203 low-risk and 33 with hypertension) scheduled to undergo elective caesarean section. The mean arterial blood pressure and pulsatility indexes for the uterine and umbilical arteries were recorded before and after spinal anaesthesia was performed using 8–9 mg hyperbaric bupivacaine (5 mg/mL) and 2–2.5 μg sufentanil (5 μg/mL). Multiple linear regression models with errors capable of correlation or with unequal variances were fitted using the generalized least squares. Results: In normotensive women, the mean arterial blood pressure decreased after administering spinal anaesthesia (p < 0.05). The pulsatility index of the uterine and umbilical arteries did not change after spinal anaesthesia. In the hypertensive women, the mean arterial blood pressure (p < 0.05) and uterine artery pulsatility index (p < 0.05) decreased. In both groups, the umbilical artery pulsatility index did not change after spinal anaesthesia. Conclusions: In stage-1 chronic hypertensive pregnant women at term, spinal anaesthesia for caesarean section reduces uterine artery impedance but not umbilical artery impedance. Electronic supplementary material The online version of this article (doi:10.1186/1471-2393-14-291) contains supplementary material, which is available to authorized users

Factors associated with leisure-time physical activity among patients undergoing hemodialysis

Background End-stage renal disease patients are characterized by low levels of physical activity, especially during leisure time. However, the recognition of variables associated with patterns of physical activity in this population has been little explored. Thus, the objective was to assess factors associated with levels of physical activity during leisure time among patients on haemodialysis. Methods Ninety-eight patients (51.6 ± 15.7 years, 57 M/41 F) from two dialysis centres in São Paulo, Brazil participated in this cross-sectional study. Participants were divided into those who never exercised during leisure-time (inactive) and those who exercised at least once a week (active). The independent factors assessed were: socio-demographic data, comorbidities, personal barriers to exercise and physical activity records from childhood to adulthood (tracking of physical activity). Results Only 27 % of patients were engaged in PA during their leisure time at least once a week. Patients who engaged in regular physical activity during adulthood before the initiation of the hemodialysis treatment (adjusted OR: 7.24 95 % IC: 1.99; 26.50), those who developed the renal disease through diseases other than diabetes or hypertension (adjusted OR: 4.82; 95 % IC: 1.48; 15.68), and those who had no cardiovascular diseases (adjusted OR: 11.33; 95 % IC: 1.23; 103.8) where more likely to be active during their leisure-time. Conclusion Comorbidities such as cardiovascular disease, hypertension and diabetes mellitus as well as the level of physical activity prior to end-stage renal disease could predict leisure-time physical activity among patients receiving hemodialysis therapy

Antiphospholipid Syndrome Risk Evaluation

The antiphospholipid syndrome is an acquired autoimmune disorder produced by high titers of antiphospholipid antibodies that cause both arterial and veins thrombosis as well as pregnancy-related complications and morbidity, as clinical manifestations. This autoimmune hypercoagulable state, often associated with coronary artery disease and recurrent Acute Myocardium Infraction, has severe consequences for the patients, being one of the main causes of thrombotic disorders and death. Therefore, it is extremely important to be preventive; being aware of how probable is to have that kind of syndrome. Despite the updated of the APS classification published as Sydney criteria, diagnosis of this syndrome remains challenging. Further research on clinically relevant antibodies and standardization of their quantification are required to improve clinical risk assessment in APS. This work will focus on the development of a diagnosis support system to antiphospholipid syndrome, built under a formal framework based on Logic Programming, in terms of its knowledge representation and reasoning procedures, complemented with an approach to computing grounded on Artificial Neural Networks. The proposed model allowed to improve the diagnosis, classifying properly the patients that really presented this pathology (sensitivity about 92%) as well as classifying the absence of APS (specificity ranging from 89% to 94%)

Fast calculation of spectral optical properties and pigment content detection in human normal and pathological kidney

A fast calculation method was used to obtain the spectral optical properties of human normal and pathological (chromophobe renal cell carcinoma) kidney tissues. Using total transmittance, total reflectance and collimated transmittance spectra acquired from ex vivo kidney samples, the spectral optical properties of both tissues, namely the absorption, the scattering and the reduced scattering coefficients, as well as the scattering anisotropy, dispersion and light penetration depth, were calculated between 200 and 1000 nm. Analysis of the mean ab sorption coefficient spectra of the kidney tissues showed that both contain melanin and lipofuscin, and that 83 % of the melanin in the normal kidney converts into lipofuscin in the pathological kidney.info:eu-repo/semantics/publishedVersio

Antioxidant activity of chitooligosaccharides upon two biological systems: erythrocytes and bacteriophages

Most of the reports to date on the antioxidant capacity of chitosans and chitooligosaccharides (COS) are based on strictly chemical methods. When studying antioxidants with potential in vivo applications, the method used to evaluate the antioxidant activity should be representative of the conditions in which the antioxidant might have a protective effect. In this work we evaluate the antioxidant activity of two COS mixtures and a low MW chitosan (LMWC) upon two biological oxidizable substrates – erythrocytes and phages, subjected to accelerated oxidation conditions. Our results suggest that COS/LMWC can be used as antioxidants in biological systems. All the tested compounds reduced either the hemolytic and DNA damage, by inhibiting H2O2- and AAPH-radicals. However, the results obtained for these biological assays did not reveal a dose dependence, contrary to the chemical assay, suggesting that the protective concentrations should be established, in order to prevent enhancement of the oxidative damage – i.e. a prooxidant effect.info:eu-repo/semantics/acceptedVersio

Expression of histone methyltransferases as novel biomarkers for renal cell tumor diagnosis and prognostication

Renal cell tumors (RCTs) are the most lethal of the common urological cancers. The widespread use of imaging entailed an increased detection of small renal masses, emphasizing the need for accurate distinction between benign and malignant RCTs, which is critical for adequate therapeutic management. Histone methylation has been implicated in renal tumorigenesis, but its potential clinical value as RCT biomarker remains mostly unexplored. Hence, the main goal of this study was to identify differentially expressed histone methyltransferases (HMTs) and histone demethylases (HDMs) that might prove useful for RCT diagnosis and prognostication, emphasizing the discrimination between oncocytoma (a benign tumor) and renal cell carcinoma (RCC), especially the chromophobe subtype (chRCC). We found that the expression levels of three genes-SMYD2, SETD3, and NO66-was significantly altered in a set of RCTs, which was further validated in a large independent cohort. Higher expression levels were found in RCTs compared to normal renal tissues (RNTs) and in chRCCs comparatively to oncocytomas. SMYD2 and SETD3 mRNA levels correlated with protein expression assessed by immunohistochemistry. SMYD2 transcript levels discriminated RCTs from RNT, with 82.1% sensitivity and 100% specificity (AUC=0.959), and distinguished chRCCs from oncocytomas, with 71.0% sensitivity and 73.3% specificity (AUC: 0.784). Low expression levels of SMYD2, SETD3, and NO66 were significantly associated with shorter disease-specific and disease-free survival, especially in patients with non-organ confined tumors. We conclude that expression of selected HMTs and HDMs might constitute novel biomarkers to assist in RCT diagnosis and assessment of tumor aggressiveness.This study was funded by research grants from Research Center of Portuguese Oncology Institute – Porto (CI-IPOP 4-2012) and European Community’s Seventh Framework Program – Grant number FP7-HEALTH-F5-2009-241783. ASP-L and FQV are and were supported by FCT-Fundação para a Ciência e a Tecnologia grants (SFRH/SINTD/94217/2013 and SFRH/ BD/70564/2010, respectively)

PROENC: PROGRAMA DE ENSINO DE CIÊNCIAS

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