Luís Guedes-Martins

Prof. Luís Guedes-Martins

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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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JLJoana Cardoso Ferreira Mota Lourenço
Joana Cardoso Ferreira Mota Lourenço
LGLuís Guedes-Martins
Luís Guedes-Martins
Obesity is one of the biggest health problems in the 21st century and the leading health disorder amongst women of fertile age. Maternal obesity is associated with several adverse maternal and fetal outcomes. In this group of women, the risk for the development of hypertensive disorders of pregnancy (HDPs), such as gestational hypertension (GH) and pre-eclampsia (PE), is increased. In fact, there is a linear association between an increase in pre-pregnancy body mass index (BMI) and PE. Excessive weight gain during pregnancy is also related to the development of PE and GH. The role of obesity in the pathophysiology of HDP is complex and is most likely due to an interaction between several factors that cause a state of poor maternal cardiometabolic health. Adipokines seem to have a central role in HDP development, especially for PE. Hypoadiponectinemia, hyperleptinemia, insulin resistance (IR), and a proinflammatory state are metabolic disturbances related to PE pathogenesis, contributing to its development by inducing a state of maternal endothelial dysfunction. Hypertriglyceridemia is suggested to also be a part of the disease mechanisms of HDP. Therefore, this review seeks to explore the scientific literature to assess the complications of maternal obesity and its association with the development of HDP.

25 June 2013 in Free Radical Research
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LGLuís Guedes-Martins
Luís Guedes-Martins
LML. Matos
L. Matos
ASA. Soares
A. Soares
Elisabete Ferreira SilvaElisabete Ferreira Silva
Elisabete Ferreira Silva
Henrique AlmeidaHenrique Almeida
Henrique Almeida
Glycation of proteins or other biomolecules and their further long-term degradation result in the formation of advanced glycation end products, AGEs. AGEs and other ligands interact with their receptors, RAGEs, localized to a variety of tissues, but mainly in endothelium and vascular wall cells. This interaction triggers diverse signaling pathways that converge on the activation of NF-κB and the initiation of a local inflammatory reaction that, when prolonged, results in dysfunctional features. Preeclampsia is a serious vascular disorder centred at the placenta–uterine interface, the placental bed, but the condition extends to the mother´s circulation. RAGEs have notorious expression in the placental bed tissues along pregnancy but, in addition, RAGEs and their ligands are expressed in the fetal membranes and are found in the amniotic fluid and the mother´s serum. Disorders complicating pregnancies and having an important vascular involvement, as preeclampsia and diabetes mellitus, have additional enhanced AGE/RAGE expression variation. This indicates that for their assessment, the assay of RAGEs or their ligands may become useful diagnostic or prognostic procedures.

5 March 2015 in PLOS ONE
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LGLuís Guedes-Martins
Luís Guedes-Martins
RGRita Gaio
Rita Gaio
JSJoaquim Saraiva
Joaquim Saraiva
SCSofia Cerdeira
Sofia Cerdeira
LMLiliana Matos
Liliana Matos
Henrique AlmeidaHenrique Almeida
Henrique Almeida
Cyclic endometrial neoangiogenesis contributes to changes in local vascular patterns and is amenable to non-invasive assessment with Doppler sonography. We hypothesize that the uterine artery (UtA) impedance, measured by its pulsatility index (PI), exhibits a regular pattern during the normal menstrual cycle. Therefore, the main study objective was to derive normative new day-cycle-based reference ranges for the UtA-PI during the entire cycle from days 1 to 34 according to the isolated time effect and potential confounders such as age and parity. From January 2009 to December 2012, a cross-sectional study of 1,821 healthy women undergoing routine gynaecological ultrasound was performed. The Doppler flow of the right and left UtA-PI was studied transvaginally by colour and pulsed Doppler imaging. The mean right and left values and the presence or absence of a bilateral protodiastolic notch were recorded. Reference intervals for the PI according to the cycle day were generated by classical linear regression. The majority of patients (97.5%) presented unilateral or bilateral UtA notches. The crude 5th, 50th, and 95th reference percentile curves of the UtA-PI at 1–34 days of the normal menstrual cycle were derived. In all curves, a progressive significant decrease occurred during the first 13 days, followed by an increase and recovery in the UtA-PI. The adjusted 5th, 50th, and 95th reference percentile curves for the effects of age and parity were also obtained. These two conditions generated an approximately identical UtA-PI pattern during the cycle, except with small but significant reductions at the temporal extremes. The median, 5th, and the 95th percentiles of the UtA-PI decrease during the first third of the menstrual cycle and recover to their initial values during the last two thirds of the cycle. The rates of decrease and recovery depend significantly on age and parity.

1 January 2016
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LGLuís Guedes-Martins
Luís Guedes-Martins

27 January 2014 in Cardiovascular Ultrasound
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LGLuís Guedes-Martins
Luís Guedes-Martins
ACAna Cunha
Ana Cunha
JSJoaquim Saraiva
Joaquim Saraiva
RGRita Gaio
Rita Gaio
ACAna S Cerdeira
Ana S Cerdeira
Henrique AlmeidaHenrique Almeida
Henrique Almeida
The foetal aortic Doppler frequency spectrum is influenced by cardiac output and contractility of the foetal heart as well as vascular compliance, blood viscosity and impedance of the arterial vascular system. The present study aimed at comparing Doppler flow pulsatility (PI) and resistance (RI) indexes of foetal proximal descending aorta (AoF) in the first, second and third trimesters of pregnancy, in low risk women and in those with chronic arterial hypertension, who had normal pregnancy outcomes.

6 May 2019 in Current Cardiology Reviews
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MBMadalena Braga
Madalena Braga
MMMaria Lúcia Moleiro
Maria Lúcia Moleiro
LGLuís Guedes-Martins
Luís Guedes-Martins
The ductus venosus is a vascular shunt situated within the fetal liver parenchyma, connecting the umbilical vein to the inferior vena cava. This vessel acts as a bypass of the liver microcirculation and plays a critical role in the fetal circulation. The ductus venosus allows oxygenated and nutrient-rich venous blood to flow from the placenta to the myocardium and brain. Increased impedance to flow in the fetal ductus venosus is associated with fetal aneuploidies, cardiac defects and other adverse pregnancy outcomes. This review serves to improve our understanding of the mechanisms that regulate the blood flow redistribution between the fetal liver circulation and fetal heart and the clinical significance of the ductus venosus waveform as generated by pressure-volume changes in the fetal heart.