6 results on '"Chronopoulou E"'
Search Results
2. Endogenous progesterone in unexplained infertility: a systematic review and meta-analysis.
- Author
-
Raperport C, Chronopoulou E, Homburg R, Khan K, and Bhide P
- Subjects
- Female, Humans, Endometrium metabolism, Corpus Luteum metabolism, Progesterone, Infertility, Female etiology
- Abstract
Purpose: To investigate the possibility that altered actions of endogenous progesterone affect receptivity and contribute to unexplained infertility (UI)., Methods: Two authors electronically searched MEDLINE, CINAHL and Embase databases from inception to 6 July 2022 and hand-searched according to Cochrane methodology. We included all published primary research reporting outcomes related to endogenous progesterone in natural cycles in women with UI. Studies were assessed for risk of bias using a modified Newcastle-Ottawa Score or NHLBI Score. We pooled results where appropriate using a random-effects model. Findings were reported as odds ratios or mean differences., Results: We included 41 studies (n = 4023). No difference was found between the mid-luteal serum progesterone levels of women with UI compared to fertile controls (MD 0.74, - 0.31-1.79, I
2 36%). Women with UI had significantly higher rates of 'out-of-phase' endometrium than controls. Nine out of 10 progesterone-mediated markers of endometrial receptivity were significantly reduced in women with UI compared to fertile controls (the remaining 1 had conflicting results). Resistance in pelvic vessels was increased and perfusion of the endometrium and sub-endometrium reduced in UI compared to fertile controls in all included studies. Progesterone receptor expression and progesterone uptake were also reduced in women with unexplained infertility., Conclusions: End-organ measures of endogenous progesterone activity are reduced in women with UI compared to fertile controls. This apparently receptor-mediated reduction in response affects endometrial receptivity and is implicated as the cause of the infertility. Further research is required to confirm whether intervention could overcome this issue, offering a new option for treating unexplained infertility., Trial Registration: PROSPERO registration: CRD42020141041 06/08/2020., (© 2022. The Author(s).)- Published
- 2023
- Full Text
- View/download PDF
3. Elective oocyte cryopreservation for age-related fertility decline.
- Author
-
Chronopoulou E, Raperport C, Sfakianakis A, Srivastava G, and Homburg R
- Subjects
- Aging genetics, Counseling, Cryopreservation, Female, Fertility genetics, Humans, Live Birth epidemiology, Live Birth genetics, Pregnancy, Aging physiology, Fertility physiology, Fertility Preservation, Oocytes growth & development
- Abstract
Purpose: Women who pursue fertility at an advanced age are increasingly common. Family planning and sexual education have traditionally focused on contraception and prevention of sexually transmitted diseases. A focus should now also be placed on fertility awareness and fertility preservation. This manuscript aims to give an update on the existing evidence around elective oocyte cryopreservation, also highlighting the need for fertility education and evidence-based, individualized counselling., Methods: A thorough electronic search was performed from the start of databases to March 2020 aiming to summarize the existing evidence around elective egg freezing, the logic behind its use, patient counselling and education, success rates and risks involved, regulation, cost-effectiveness, current status and future perspectives., Results: Clinician-led counselling regarding reproductive aging and fertility preservation is often overlooked. Elective oocyte cryopreservation is not a guarantee of live birth, and the answer regarding cost-effectiveness needs to be individualized. The existing studies on obstetric and perinatal outcomes following the use of egg freezing are, until now, reassuring. Constant monitoring of short-term and long-term outcomes, uniform regulation and evidence-based, individualized counselling is of paramount importance., Conclusions: Elective oocyte cryopreservation is one of the most controversial aspects of the world of assisted reproduction, and a lot of questions remain unanswered. However, women today do have this option which was not available in the past. Elective oocyte cryopreservation for age-related fertility decline should be incorporated in women's reproductive options to ensure informed decisions and reproductive autonomy.
- Published
- 2021
- Full Text
- View/download PDF
4. Delineation of the functional and structural properties of the glutathione transferase family from the plant pathogen Erwinia carotovora.
- Author
-
Theoharaki C, Chronopoulou E, Vlachakis D, Ataya FS, Giannopoulos P, Maurikou S, Skopelitou K, Papageorgiou AC, and Labrou NE
- Subjects
- Bacterial Proteins genetics, Bacterial Proteins metabolism, Erwinia genetics, Glutathione Transferase genetics, Glutathione Transferase metabolism, Phylogeny, Protein Conformation, Bacterial Proteins chemistry, Erwinia enzymology, Glutathione Transferase chemistry
- Abstract
Erwinia carotovora, a widespread plant pathogen that causes soft rot disease in many plants, is considered a major threat in agriculture. Bacterial glutathione transferases (GSTs) play important roles in a variety of metabolic pathways and processes, such as the biodegradation of xenobiotics, protection against abiotic stress, and resistance against antimicrobial drugs. The GST family of canonical soluble enzymes from Erwinia carotovora subsp. atroseptica strain SCRI1043 (EcaGSTs) was investigated. Genome analysis showed the presence of six putative canonical cytoplasmic EcaGSTs, which were revealed by phylogenetic analysis to belong to the well-characterized GST classes beta, nu, phi, and zeta. The analysis also revealed the presence of two isoenzymes that were phylogenetically close to the omega class of GSTs, but formed a distinct class. The EcaGSTs were cloned and expressed in Escherichia coli, and their catalytic activity toward different electrophilic substrates was elucidated. The EcaGSTs catalyzed different types of reactions, although all enzymes were particularly active in reactions involving electrophile substitution. Gene and protein expression profiling conducted under normal culture conditions as well as in the presence of the herbicide alachlor and the xenobiotic 1-chloro-2,4-dinitrobenzene (CDNB) showed that the isoenzyme EcaGST1, belonging to the omega-like class, was specifically induced at both the protein and mRNA levels. EcaGST1 presumably participates in counteracting the xenobiotic toxicity and/or abiotic stress conditions, and may therefore represent a novel molecular target in the development of new chemical treatments to control soft rot diseases.
- Published
- 2019
- Full Text
- View/download PDF
5. The curious case of premature luteinization.
- Author
-
Kaponis A, Chronopoulou E, and Decavalas G
- Subjects
- Chorionic Gonadotropin therapeutic use, Female, Humans, Ovulation Induction adverse effects, Pregnancy, Pregnancy Rate, Premature Birth, Fertilization in Vitro, Gonadotropin-Releasing Hormone metabolism, Luteinization, Progesterone metabolism
- Abstract
Purpose: Premature luteinization (PL) affects 12.3-46.7% of fresh in vitro fertilization cycles, and there is accumulating evidence confirming its negative effect on success rates. However, despite its clinical significance, PL is poorly understood and defined. This narrative review aims to provide a fresh look at the phenomenon of PL by summarizing the existing evidence and re-evaluating fundamental issues., Methods: A thorough electronic search was conducted covering the period from 1978 until January 2018 in PubMed, Embase, and Medline databases, and references of relevant studies were cross-checked. Meeting proceedings of the European Society of Human Reproduction and Embryology and the American Society for Reproductive Medicine were also hand searched., Results: In the curious case of PL, one should go back to the beginning and re-consider every step of the way. The pathogenesis, definition, measurement methods, clinical implications, and management strategies are discussed in detail, highlighting controversies and offering "food for thought" for future directions., Conclusions: Authors need to speak the same language when studying PL in order to facilitate comparisons. The terminology, progesterone cut-off, measurement methods and days of measurement should be standardized and globally accepted; otherwise, there can be no scientific dialog. Future research should focus on specific patient profiles that may require a tailored approach. Progesterone measurements throughout the follicular phase possibly depict the progesterone exposure better than an isolated measurement on the day of hCG. Adequately powered randomized controlled trials should confirm which the best prevention and management plan of PL is, before introducing any strategy into clinical practice.
- Published
- 2018
- Full Text
- View/download PDF
6. Plant glutathione transferase-mediated stress tolerance: functions and biotechnological applications.
- Author
-
Nianiou-Obeidat I, Madesis P, Kissoudis C, Voulgari G, Chronopoulou E, Tsaftaris A, and Labrou NE
- Subjects
- Biodegradation, Environmental, Plant Growth Regulators metabolism, Biotechnology methods, Glutathione Transferase metabolism
- Abstract
Plant glutathione transferases (EC 2.5.1.18, GSTs) are an ancient, multimember and diverse enzyme class. Plant GSTs have diverse roles in plant development, endogenous metabolism, stress tolerance, and xenobiotic detoxification. Their study embodies both fundamental aspects and agricultural interest, because of their ability to confer tolerance against biotic and abiotic stresses and to detoxify herbicides. Here we review the biotechnological applications of GSTs towards developing plants that are resistant to biotic and abiotic stresses. We integrate recent discoveries, highlight, and critically discuss the underlying biochemical and molecular pathways involved. We elaborate that the functions of GSTs in abiotic and biotic stress adaptation are potentially a result of both catalytic and non-catalytic functions. These include conjugation of reactive electrophile species with glutathione and the modulation of cellular redox status, biosynthesis, binding, and transport of secondary metabolites and hormones. Their major universal functions under stress underline the potential in developing climate-resilient cultivars through a combination of molecular and conventional breeding programs. We propose that future GST engineering efforts through rational and combinatorial approaches, would lead to the design of improved isoenzymes with purpose-designed catalytic activities and novel functional properties. Concurrent GST-GSH metabolic engineering can incrementally increase the effectiveness of GST biotechnological deployment.
- Published
- 2017
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.