Nikos Vlahos - Academia.edu (original) (raw)

Papers by Nikos Vlahos

Journal of Assisted Reproduction and Genetics, 2020

Objective Combination of transcriptomic and retrospective clinical data, to assess anti-Mullerian... more Objective Combination of transcriptomic and retrospective clinical data, to assess anti-Mullerian hormone (AMH) functionality at a cumulus cell level and evaluate AMH potential as a suitable marker for IVF outcomes (oocytes retrieved, number of day 3 embryos, gestation outcomes). Design Raw RNA-sequencing data of cumulus cells sourced from younger (n = 10) patient group (group A) (age 29 (1 year of age), baseline FSH 7.4 (0.5 mIU/ml), AMH 4.67 (1.56 ng/ml)) and older (n = 10) patient group (group B) (age 43 (± 0.55 years of age), baseline FSH 8 (0.8 mIU/ml), AMH 1.07 (0.44 ng/ml)) were employed to derive transcriptomic differences among high vs. low AMH groups. We collected retrospectively patient data from 80 infertile patients selected according to pre-specified inclusion criteria. Setting Publicly available raw RNA-sequencing data were retrieved from the SRA database of NCBI resource GEO Accession (GSM21575/35-44; GEO Accession: GSM21575/45-55). Retrospective data were collected ...

International journal of gynecological cancer : official journal of the International Gynecological Cancer Society, 2010

A debate exists about whether glutathione S-transferase (GST) polymorphisms (GST mu-1 [GSTM1] nul... more A debate exists about whether glutathione S-transferase (GST) polymorphisms (GST mu-1 [GSTM1] null/present genotype and GST theta-1 [GSTT1] null/present genotype) confer additional risk for cervical cancer. This meta-analysis was aimed to examine the associations between the aforementioned polymorphisms and cervical cancer risk. Thirteen studies were eligible for GSTM1 (1616 cervical cancer cases and 1970 controls), and 12 studies were eligible for GSTT1 (1393 cases and 1766 controls). Pooled odds ratios (OR) were appropriately derived from fixed effects or random effects models. Separate analyses were conducted on Chinese and non-Chinese populations. Metaregression with publication year was also performed. At the overall analysis, the GSTM1 null genotype was associated with increased cervical cancer risk (pooled OR = 1.272; 95% confidence interval [CI], 1.014-1.597, random effects). The association seemed confined to non-Chinese populations (pooled OR = 1.392; 95% CI, 1.003-1.932, ...

Current Obstetrics and Gynecology Reports, 2012

A fastidious fertility evaluation designed to discern all factors contributing to a couple's inab... more A fastidious fertility evaluation designed to discern all factors contributing to a couple's inability to conceive is the quintessential approach to a well-justified, costeffective treatment plan. The purpose of this review is to outline the steps of female infertility evaluation as well as all evidence-based methods in a reproductive endocrinologist's armamentarium to perform it. Evaluation should always start with the least invasive approaches for detection of the most common causes of infertility. The most common identifiable causes of female infertility include ovulatory disorders, tubal blockade or other reproductive tract pathology (irregular cervical mucus production, endometriosis, pelvic adhesions), and/or other medical condition interacting with the above (hyperprolactinemia, thyroid disorder). Incessant advancement of Assisted Reproductive Technology techniques renders more and more infertility causes amenable to treatment; a rational use of available approaches in terms of both personalized feasibility and cost-effectiveness should be applied.

Archives of gynecology and obstetrics, Jan 3, 2015

Recurrence of endometriosis after conservative surgery has been observed in 40-50 % of patients w... more Recurrence of endometriosis after conservative surgery has been observed in 40-50 % of patients within the first 5 years. A variety of regimens such as combined oral contraceptives, GnRH agonists, danazol, and progestins have been used postoperatively to reduce recurrence rates. Oral contraceptives (oCP) have been used either in a cyclic or in a continuous (no pill-free interval) fashion. The purpose of this article was to summarize the existing evidence on the efficacy and patient compliance for the use of oCP in a continuous versus cyclic fashion following conservative surgery for endometriosis. A systematic search of Medline identified four eligible studies. Studies were considered eligible, if they have evaluated oCP therapy, either in a cyclic or continuous regimen, after conservative surgery for endometriosis. Specifically, studies (1) reporting on women with endometriosis who were treated postoperatively with both continuous oCP and cyclic oCP, (2) written in English, (3) wit...

Reproductive BioMedicine Online, 2015

The use of dehydroepiandrosterone (DHEA) may improve ovarian stimulation outcomes in women of adv... more The use of dehydroepiandrosterone (DHEA) may improve ovarian stimulation outcomes in women of advanced reproductive age and could reduce embryo aneuploidy. In this prospective study, 48 women diagnosed with poor ovarian response received DHEA supplementation for at least 12 weeks. These women were compared with a group of poor responders (n = 113) who did not receive supplementation. During the study period, patients taking day 2 FSH and oestradiol were measured monthly before and after treatment. Stimulation characteristics, stimulation outcome and clinical outcome (clinical pregnancy and live birth rates) were reported. Evaluation of anti-Müllerian hormone (AMH) was carried out before initiation of treatment and immediately before the subsequent stimulation. Supplementation with DHEA for at least 12 weeks resulted in a modest, but statistically significant, increase in AMH levels and decrease in baseline FSH (P < 0.001 and P = 0.007, respectively). Administration of DHEA had no effect on any of the stimulation parameters nor was there any difference in clinical pregnancy rates and live birth rates between the two groups. Supplementation with DHEA significantly affects women with poor prognosis undergoing ovarian stimulation for IVF. Patients should be counselled about the uncertain effectiveness, potential side-effects and cost of this treatment.

Molecular Biology Reports, 2012

This meta-analysis aims to examine whether the genotype status of MspI and Ile462Val polymorphism... more This meta-analysis aims to examine whether the genotype status of MspI and Ile462Val polymorphisms in Cytochrome-P450 1A1 (CYP1A1) is associated with cervical cancer risk. Eligible case-control studies were identified through search in MEDLINE (end of search: October 2010). Pooled odds ratios (ORs) were appropriately derived from fixed-effects or random effects models. Concerning MspI polymorphism, six studies were eligible (722 cases and 770 controls); four studies were eligible (350 cases and 519 controls) for Ile462Val. MspI polymorphism was associated with elevated cervical cancer risk (for heterozygous TC vs. TT carriers OR = 1.50, 95% CI: 0.93-2.42, random effects; for homozygous CC vs. TT carriers OR = 2.66, 95% CI: 1.14-6.19, random effects). Similarly, Ile462Val polymorphism was associated with elevated cervical cancer risk (for heterozygous Ile/Val vs. Ile/Ile carriers OR = 2.36, 95% CI: 1.10-5.08, random effects; for homozygous Val/Val vs. Ile/Ile carriers OR = 2.73, 95% CI: 1.21-6.15, fixed effects). The results were replicated upon Caucasian subjects, who represented the majority of existing data. The two examined CYP1A1 genotype polymorphisms seem to confer additional risk for cervical cancer. Accumulation of further data seems mandatory for future race-specific analyses and for the demonstration of CYP1A1-smoking interactions.

International Journal of Gynecological Cancer, 2011

Introduction:This meta-analysis aims to examine whether the genotype status of Msp1, Ile462Val, a... more Introduction:This meta-analysis aims to examine whether the genotype status of Msp1, Ile462Val, and Thr461Asn polymorphisms in cytochrome P450 1A1 (CYP1A1) is associated with endometrial cancer risk.Methods:Eligible case-control studies were identified through search in MEDLINE (end of search: August 2010). Pooled odds ratios (ORs) were appropriately derived from fixed-effects or random-effects models.Results:Concerning MspI polymorphism, 8 studies were eligible (1456 cases and 2371 controls); 9 studies were eligible (1889 cases and 3662 controls) for Ile462Val and 6 studies were eligible (1272 cases and 2122 controls) for Thr461Asn. MspI polymorphism was not associated with endometrial cancer risk (for heterozygous TC vs TT carriers: OR = 0.83, 95% confidence interval [CI], 0.59-1.15, random effects; for homozygous CC vs TT carriers: OR = 1.00, 95% CI, 0.55-1.82, fixed effects). Similarly, Ile462Val polymorphism was not associated with endometrial cancer risk (for heterozygous Ile/...

Fertility and Sterility, 2009

Objective: To present a case of aberrant follicular development, acquisition of mature oocytes, a... more Objective: To present a case of aberrant follicular development, acquisition of mature oocytes, and pregnancy after 2 weeks of leuprolide acetate administration during the midluteal phase. Design: Case report.

Best Practice & Research Clinical Obstetrics & Gynaecology, 2010

appropriate statistical power and follow-up time are required to evaluate accurately the long-ter... more appropriate statistical power and follow-up time are required to evaluate accurately the long-term effects of these drugs and procedures.

Annals of the New York Academy of Sciences, 2010

There is evidence that medications used for ovarian stimulation and in vitro fertilization may be... more There is evidence that medications used for ovarian stimulation and in vitro fertilization may be associated with ovarian cancer. In this review, we attempt to describe this relationship according to the most recent epidemiologic data and to present the possible mechanisms on the molecular level that could potentially explain this correlation. Currently there is no proven relationship between any type of ovarian cancer and drugs used for infertility treatment. Overall, infertile women have increased risk for ovarian malignancies. Nulligravidas that received treatment are at increased risk for ovarian malignancy as compared to women that conceived after treatment. More studies with the appropriate statistical power and follow-up time, as well as with better adjustment for confounding factors, which coexist in infertile patients, are required to evaluate accurately the long-term effects of these drugs and procedures.

International Journal of Gynecology & Obstetrics, 2008

Obstetrics, Gynaecology & Reproductive Medicine, 2011

Ovarian hyperstimulation syndrome (OHSS) is considered as one of the significant complications of... more Ovarian hyperstimulation syndrome (OHSS) is considered as one of the significant complications of assisted conception. Its presentation may vary in severity with the mild form affecting about 33% and the more severe forms seen in around 3–8% of in-vitro fertilization (IVF) cycles. Exact aetiology of OHSS is unknown but it seems to be secondary to vasoactive products released by the