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1.
Biomedicines ; 11(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38002013

RESUMO

BACKGROUND: Mitochondrial dysfunction is a risk factor in the pathogenesis of metabolic disorders. According to the energy requirements, oxidative phosphorylation and the electron transport chain work together to produce ATP in sufficient quantities in the mitochondria of eukaryotic cells. Abnormal mitochondrial activity causes fat accumulation and insulin resistance as cells require a balance between the production of ATP by oxidative phosphorylation (OXPHOS) in the mitochondria and the dissipation of the proton gradient to reduce damage from reactive oxygen species (ROS). This study aims to explore the relationship between the mitochondrial content of sperm and the ratio of mitochondrial DNA to nuclear DNA in relation to body mass index (BMI) and how it may affect the progressive motility of sperm cell. Understanding the relationships between these important variables will help us better understand the possible mechanisms that could connect sperm motility and quality to BMI, as well as further our understanding of male fertility and reproductive health. METHODS: Data were collected from 100 men who underwent IVF/ICSI at the University Hospital of Ioannina's IVF Unit in the Obstetrics and Gynecology Department. The body mass index (BMI) of the males tested was used to classify them as normal weight; overweight; and obese. Evaluations included sperm morphology; sperm count; sperm motility; and participant history. RESULTS: In the group of men with normal BMI, both BMI and progressive motility displayed a statistically significant association (p < 0.05) with mitochondrial DNA content, relative mitochondrial DNA copy number, and the mtDNA/nDNA ratio. Similar to this, there was a positive association between BMI and motility in the groups of men who were overweight and obese, as well as between the expression of mitochondrial DNA and the mtDNA/nDNA ratio, with statistically significant differences (p < 0.05). There was not a statistically significant difference observed in the association between the relative mtDNA copy number and BMI or motility for the overweight group. Finally, the relative mtDNA copy number in the obese group was only associated with motility (p = 0.034) and not with BMI (p = 0.24). CONCLUSIONS: We found that in all three groups, BMI and progressive motility exhibited comparable relationships with mitochondrial DNA expression and the mtDNA/nDNA ratio. However, only in the normal group and in the obese group, the relative mitochondrial DNA copy number showed a positive association with BMI and progressive motility.

2.
Antioxidants (Basel) ; 12(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37627485

RESUMO

Oxidative stress (OS), which arises through an imbalance between the formation of reactive oxygen species (ROS) and antioxidant defenses, plays a key role in the pathophysiology of female infertility, with the latter constituting just one of a number of diseases linked to OS as a potential cause. The aim of the present article is to review the literature regarding the association between OS and female infertility. Among the reproductive diseases considered are endometriosis and polycystic ovary syndrome (PCOS), while environmental pollutants, lifestyle variables, and underlying medical conditions possibly resulting in OS are additionally examined. Current evidence points to OS likely contributing to the pathophysiology of the above reproductive disorders, with the amount of damage done by OS being influenced by such variables as duration and severity of exposure and the individual's age and genetic predisposition. Also discussed are the processes via which OS may affect female fertility, these including DNA damage and mitochondrial dysfunction. Finally, the last section of the manuscript contains an evaluation of treatment options, including antioxidants and lifestyle modification, capable of minimizing OS in infertile women. The prime message underlined by this review is the importance of considering OS in the diagnosis and treatment of female infertility. Further studies are, nevertheless required to identify the best treatment regimen and its ideal duration.

3.
Genes (Basel) ; 14(7)2023 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-37510407

RESUMO

Age-related mitochondrial markers may facilitate the prognosis of artificial reproductive technology outcomes. In this report, we present our study concerning the ratio of cf-mtDNA/cf-nDNA, namely the amount of cell-free mitochondrial DNA relative to cell-free nuclear DNA, in the follicular fluid (FF) of women undergoing IVF, aiming to generate a molecular fingerprint of oocyte quality. The values of this ratio were measured and compared among three groups of women (101 in total): (A) 31 women with polycystic ovary syndrome (PCOS), (B) 34 women younger than 36 years, and (C) 36 women older than 35 years of age. Real-time quantitative PCR (qPCR) was performed to quantify the ratio by using nuclear- and mitochondrial-specific primers and analyzed for potential correlation with age and pregnancy rate. Our analysis showed that the level of FF-cf-mtDNA was lower in the group of advanced-age women than in the groups of PCOS and non-PCOS women. Moreover, a significant positive correlation between FF-cf-mtDNA and the number of mature (MII) oocytes was observed. Collectively, the data show that the relative ratio of cf- mtDNA to cf-nDNA content in human FF can be an effective predictor for assessing the corresponding oocyte's age-related performance in IVF.


Assuntos
Líquido Folicular , Síndrome do Ovário Policístico , Gravidez , Humanos , Feminino , Líquido Folicular/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Oócitos/metabolismo , Mitocôndrias , Síndrome do Ovário Policístico/genética , Fertilização in vitro
4.
Int J Food Microbiol ; 281: 23-31, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-29803907

RESUMO

Enterococci are naturally selected for growth in thermized ewes'/goats' milk mixtures used for traditional cooked hard cheese processing in Greece. A culture-independent PCR-based approach was applied to detect the presence of enterocin-encoding genes in naturally culture-enriched thermized milk (TM). Portions of TM (63 °C, 30 s) collected from a commercial cheese plant before addition of starters were fermented at 37 °C for 48 h to facilitate growth of indigenous enterococci. The multiple enterocin-producing (m-Ent+) Enterococcus faecium KE82 and the nisin A-producing Lactococcus lactis subsp. cremoris M104 served as bacteriocin-positive inocula in separate TM treatments. The PCR results revealed a constant presence of the enterocin A, B and P genes in TM fermented naturally at 37 °C. Eleven out of 42 (26.2%) lactic isolates from the enriched TM cultures without inoculation were Ent+ E. faecium assigned to three biotypes. Biotype I (4 isolates) included single entA possessors, whereas biotype II (5 isolates) and biotype III (2 isolates) were m-Ent+ variants profiling entA-entB-entP and entA-entB genes, respectively. Biotype II displayed the strongest antilisterial activity in vitro. Surprisingly, 85.7% (6/7) of the m-Ent+ E. faecium were selectively isolated from Baird-Parker agar, reflecting their natural resistance to 0.01% tellurite contained in the egg yolk supplement. No cytolysin-positive E. faecalis or other Ent+ Enterococcus spp. were isolated. In conclusion, commercially thermized Greek milk is a natural pool or 'reservoir' of antagonistic Ent+ or m-Ent+ E. faecium strains that can be easily detected and recovered by applying this PCR-based approach to naturally fermented milks or cheese products.


Assuntos
Queijo/microbiologia , Enterococcus faecium/fisiologia , Microbiologia de Alimentos/métodos , Leite/microbiologia , Ágar , Animais , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Enterococcus/fisiologia , Enterococcus faecium/genética , Enterococcus faecium/metabolismo , Fermentação , Grécia , Lactococcus lactis/fisiologia , Leite/química , Reação em Cadeia da Polimerase , Ovinos
5.
EuroIntervention ; 10(5): 574-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24988003

RESUMO

AIMS: To develop a simplified approach of virtual functional assessment of coronary stenosis from routine angiographic data and test it against fractional flow reserve using a pressure wire (wire-FFR). METHODS AND RESULTS: Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by wire-FFR (reference standard: ≤0.80). The 3D-QCA models were processed with computational fluid dynamics (CFD) to calculate the lesion-specific pressure gradient (ΔP) and construct the ΔP-flow curve, from which the virtual functional assessment index (vFAI) was derived. The discriminatory power of vFAI for ischaemia- producing lesions was high (area under the receiver operator characteristic curve [AUC]: 92% [95% CI: 86-96%]). Diagnostic accuracy, sensitivity and specificity for the optimal vFAI cut-point (≤0.82) were 88%, 90% and 86%, respectively. Virtual-FAI demonstrated superior discrimination against 3D-QCA-derived % area stenosis (AUC: 78% [95% CI: 70- 84%]; p<0.0001 compared to vFAI). There was a close correlation (r=0.78, p<0.0001) and agreement of vFAI compared to wire-FFR (mean difference: -0.0039±0.085, p=0.59). CONCLUSIONS: We developed a fast and simple CFD-powered virtual haemodynamic assessment model using only routine angiography and without requiring any invasive physiology measurements/hyperaemia induction. Virtual-FAI showed a high diagnostic performance and incremental value to QCA for predicting wire-FFR; this "less invasive" approach could have important implications for patient management and cost.


Assuntos
Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Modelos Cardiovasculares , Idoso , Simulação por Computador , Estenose Coronária/fisiopatologia , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Expert Rev Cardiovasc Ther ; 12(7): 885-900, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24949801

RESUMO

Optical coherence tomography and intravascular ultrasound are the most widely used methodologies in clinical practice as they provide high resolution cross-sectional images that allow comprehensive visualization of the lumen and plaque morphology. Several methods have been developed in recent years to process the output of these imaging modalities, which allow fast, reliable and reproducible detection of the luminal borders and characterization of plaque composition. These methods have proven useful in the study of the atherosclerotic process as they have facilitated analysis of a vast amount of data. This review presents currently available intravascular ultrasound and optical coherence tomography processing methodologies for segmenting and characterizing the plaque area, highlighting their advantages and disadvantages, and discusses the future trends in intravascular imaging.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Tomografia de Coerência Óptica , Ultrassonografia de Intervenção , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Humanos
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