Nikos Nikolettos

Prof. Dr. Nikos Nikolettos


Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

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

Representative Publications

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PANAGIOTIS TSIKOURASPANAGIOTIS TSIKOURAS
PANAGIOTIS TSIKOURAS
Panos AntsaklisPanos Antsaklis
Panos Antsaklis
KNKonstantinos Nikolettos
Konstantinos Nikolettos
SKSonia Kotanidou
Sonia Kotanidou
NKNektaria Kritsotaki
Nektaria Kritsotaki
NNNikos Nikolettos
Nikos Nikolettos
Fetal growth restriction (FGR), or intrauterine growth restriction (IUGR), is still the second most common cause of perinatal mortality. The factors that contribute to fetal growth restriction can be categorized into three distinct groups: placental, fetal, and maternal. The prenatal application of various diagnostic methods can, in many cases, detect the deterioration of the fetal condition in time because the nature of the above disorder is thoroughly investigated by applying a combination of biophysical and biochemical methods, which determine the state of the embryo–placenta unit and assess the possible increased risk of perinatal failure outcome and potential for many later health problems. When considering the potential for therapeutic intervention, the key question is whether it can be utilized during pregnancy. Currently, there are no known treatment interventions that effectively enhance placental function and promote fetal weight development. Nevertheless, in cases with fetuses diagnosed with fetal growth restriction, immediate termination of pregnancy may have advantages not only in terms of minimizing perinatal mortality but primarily in terms of reducing long-term morbidity during childhood and maturity.

Verified
Journal Article
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AGAngeliki Gerede
Angeliki Gerede
KNKonstantinos Nikolettos
Konstantinos Nikolettos
Eleftherios VavoulidisEleftherios Vavoulidis
Eleftherios Vavoulidis
CMChrysoula Margioula-Siarkou
Chrysoula Margioula-Siarkou
SPStamatios Petousis
Stamatios Petousis
EDEkaterini Domali
Ekaterini Domali
Background/Objectives: There are indications that the microbial composition of the maternal mucosal surfaces is associated with adverse events during pregnancy. The aim of this review is to investigate the link between vaginal microbiome alterations and gestational complication risk. Methods: This comprehensive literature review was performed using Medline and Scopus databases. The following search algorithm was used, “Pregnancy Complications” [Mesh] AND (Vagin*), and after the literature screening, 44 studies were included in the final review. Results: The studies that were included investigated the association between vaginal microbial composition and preterm birth, miscarriage, preeclampsia, ectopic pregnancy, gestational diabetes mellitus, chorioamnionitis, and preterm premature rupture of membranes. In most of the studies, it was well established that increased microbial diversity is associated with these conditions. Also, the depletion of Lactobacillus species is linked to most of the gestational complications, while the increased relative abundance and especially Lactobacillus crispatus may exert a protective effect in favor of the pregnant woman. Several pathogenic taxa including Gardnerella, Prevotella, Sneathia, Bacterial Vaginosis-Associated Bacteria-2, Atopobium, and Megasphera seem to be correlated to higher maternal morbidity. Conclusions: Vaginal microbiome aberrations seem to have an association with pregnancy-related adverse events, but more high-quality homogenous studies are necessary to reliably verify this link.

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PANAGIOTIS TSIKOURASPANAGIOTIS TSIKOURAS
PANAGIOTIS TSIKOURAS
EOEfthymios Oikononou
Efthymios Oikononou
KNKonstantinos Nikolettos
Konstantinos Nikolettos
SASotiris Andreou
Sotiris Andreou
DKDimitrios Kyriakou
Dimitrios Kyriakou
NNNikos Nikolettos
Nikos Nikolettos
This review delves into the possible connection between periodontitis and negative pregnancy outcomes, such as preeclampsia and preterm birth. It highlights the potential influence of an unidentified microbial factor on preeclampsia and the effects of inflammatory responses on the rate of preterm births. Furthermore, it underscores the prevalent occurrence of oral ailments within the populace and their significant repercussions on quality of life. Hormonal fluctuations during pregnancy may exacerbate oral conditions such as pregnancy gingivitis and periodontitis, necessitating bespoke therapeutic approaches that take into account potential fetal ramifications. Periodontal disease, characterized by microbial attack and inflammatory response, results in tissue destruction and tooth loss. The oral cavity’s susceptibility to bacterial colonization, which is primarily due to its role as a site for food intake, is highlighted. Furthermore, research indicates a correlation between inflammatory responses and factors such as prostaglandin E2 and IL-1β, and preterm birth. Therapeutic interventions are a focus of international research, with efforts being aimed at optimizing outcomes through larger studies involving pregnant women.

15 March 2025 in Journal of Clinical Medicine
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AGAngeliki Gerede
Angeliki Gerede
SSSofoklis Stavros
Sofoklis Stavros
MDMaria Kiriakos Danavasis
Maria Kiriakos Danavasis
Anastasios PotirisAnastasios Potiris
Anastasios Potiris
EMEfthalia Moustakli
Efthalia Moustakli
EDEkaterini Domali
Ekaterini Domali
Preeclampsia (PE) is a multifactorial hypertensive disorder that typically manifests after the twentieth week of pregnancy, significantly impacting perinatal mortality and neonatal morbidity. Its development is influenced by immunological components, systemic inflammation, and genetic factors, with placental malfunction playing a crucial role. While many aspects of its pathophysiology have been elucidated, its key mechanisms remain incompletely understood. MicroRNAs (miRNAs), small noncoding RNA molecules that regulate gene expression, have emerged as promising biomarkers and therapeutic targets in PE. Dysregulated miRNAs have been identified in pregnant PE patients, highlighting their role in disease onset. Placenta-specific miRNAs, such as miR-210 and miR-155, influence inflammation, endothelial function, and hypoxia responses, which are closely associated with PE development. These miRNAs play a crucial role in regulating trophoblast invasion, angiogenesis, and immune modulation, further linking their dysregulation to the pathophysiology of PE. This review aims to provide a comprehensive overview of the role of miRNAs in PE, focusing on their potential as diagnostic biomarkers and therapeutic targets. By integrating recent advancements in molecular research, we explore their implications in clinical practice, particularly in risk assessment, early detection, and novel treatment strategies.

Verified
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PANAGIOTIS TSIKOURASPANAGIOTIS TSIKOURAS
PANAGIOTIS TSIKOURAS
EOEfthymios Oikononou
Efthymios Oikononou
ABAnastasia Bothou
Anastasia Bothou
PCPenelopi Chaitidou
Penelopi Chaitidou
DKDimitrios Kyriakou
Dimitrios Kyriakou
NNNikos Nikolettos
Nikos Nikolettos
Despite the increased frequency of endometriosis, it remains one of the most enigmatic disorders regarding its effects on pregnancy. Endometriosis adversely affects both natural and assisted conception. Impaired folliculogenesis, which causes follicular dysfunction and low egg quality, as well as luteal phase problems, reduced fertilization, and abnormal embryogenesis, are some of the mechanisms advocated to explain reproductive dysfunction. There is a rising need for a comprehensive study of the potential negative consequences of this condition on pregnancy outcomes, including the postpartum period, as more women with a medical history of endometriosis become pregnant. Obstetrical complications (small for gestational age [SGA], cesarean section [CS], miscarriage, hemorrhage, low placental adhesion, and preterm delivery) are statistically elevated in women with endometriosis. Furthermore, ruptured ovarian endometrioma, appendicitis, intestinal perforation, and hemoperitoneum have been described in pregnancy. Obstetricians are largely unfamiliar with these complications, as they have not been thoroughly investigated. The development and pathogenesis of endometriosis is an important field of study and has not yet been fully elucidated. Finding these mechanisms is crucial for the development of new and more effective strategies to treat this condition. Endometriosis can have an impact on obstetric and neonatal outcomes of pregnancy, in addition to its potential effects on conception. To date, no additional monitoring is recommended for pregnancies with a history of endometriosis. However, more studies are urgently needed to assess the need for the tailored pregnancy monitoring of women with endometriosis.

29 January 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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PANAGIOTIS TSIKOURASPANAGIOTIS TSIKOURAS
PANAGIOTIS TSIKOURAS
KNKonstantinos Nikolettos
Konstantinos Nikolettos
SKSonia Kotanidou
Sonia Kotanidou
NKNektaria Kritsotaki
Nektaria Kritsotaki
EOEfthymios Oikononou
Efthymios Oikononou
NNNikos Nikolettos
Nikos Nikolettos
Objective: Pre-eclampsia (PE) is a complex, advancing condition marked either by the recent emergence of hypertension and proteinuria or by the recent onset of hypertension accompanied by notable end-organ impairment, which may occur with or without proteinuria. PE usually appears in the postpartum phase or after the 20th week of gestation, though it might appear sooner in cases of molar pregnancy. Pathophysiology: This disorder is a serious multisystem condition during pregnancy that can lead to serious, life-threatening complications for both the mother and the fetus if it is not diagnosed and managed promptly. These changes result from widespread and intense vasoconstriction caused by renin, angiotensin II (Ang II), aldosterone, and catecholamines. The renin–angiotensin–aldosterone system (RAAS) and its sequence of signaling reactions demonstrate its crucial role in regulating blood pressure and electrolyte balance that diverges in PE from that observed in healthy pregnancies. However, it is widely recognized that the above description is incomplete for pre-eclampsia and further relationships should be analyzed. The purpose of this article is to review and synthesize alterations in renal function and the RAAS during normal pregnancy and pre-eclampsia. We aim to provide clinical gynecologists with a comprehensive understanding of how pregnancy-specific adaptations can impact renal function and the RAAS, as well as the deviations observed in pre-eclampsia. Conclusion: This information is essential to enhance clinical awareness, improve the accuracy of diagnosis, and support evidence-based decision-making in the management of pregnant patients, especially those complicated by pre-eclampsia.