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Featured researches published by J. Bontis.


Fertility and Sterility | 2009

How to improve the probability of pregnancy in poor responders undergoing in vitro fertilization: a systematic review and meta-analysis

Dimitra Kyrou; Efstratios M. Kolibianakis; Christos A. Venetis; E.G. Papanikolaou; J. Bontis; Basil C. Tarlatzis

OBJECTIVE To systematically review the literature to identify randomized controlled trials, which evaluate interventions aiming to improve the probability of pregnancy in poor responders undergoing in vitro fertilization (IVF). DESIGN Systematic review and meta-analysis. SETTING University-based hospital. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Pregnancy rate. RESULT(S) Twenty-two eligible randomized controlled trials were identified that evaluated in total 15 interventions to increase pregnancy rates in poor responders. Based on limited evidence, the only interventions that appear to increase the probability of pregnancy were the addition of GH to ovarian stimulation (odds ratio for live birth: 5.22, confidence interval: 95% 1.09-24.99) and the performance of embryo transfer on day 2 compared with day 3 (ongoing pregnancy rate: 27.7% vs. 16.3%, respectively; difference: +11.4, 95% confidence interval: +1.6 to +21.0). CONCLUSION(S) Insufficient evidence exists to recommend most of the treatments proposed to improve pregnancy rates in poor responders. Currently, there is some evidence to suggest that addition of GH, as well as performing embryo transfer on day 2 versus day 3, appear to improve the probability of pregnancy.


Current Pharmaceutical Biotechnology | 2012

Significantly Lower Pregnancy Rates in the Presence of Progesterone Elevation in Patients Treated with GnRH Antagonists and Gonadotrophins: A Systematic Review and Meta-Analysis

Efstratios M. Kolibianakis; Christos A. Venetis; J. Bontis; Basil C. Tarlatzis

The current meta-analysis aimed to answer the following research question: is progesterone elevation on the day of hCG administration associated with the probability of clinical pregnancy in women undergoing ovarian stimulation for IVF using GnRH antagonists? A literature search in MEDLINE, EMBASE and CENTRAL electronic databases followed by extensive hand-searching from two independent reviewers was performed to identify relevant studies. Eventually five eligible studies (n=585 patients) were identified. No significant differences were present between patients with and those without progesterone elevation regarding female age, duration of stimulation and total dose of gonadotrophins required. However, patients with progesterone elevation were characterized by higher serum estradiol levels on the day of hCG administration (+956 pg/ml, 95% +248 to +1664, random effects model, p=0.008) and more COCs retrieved (+2.9, 95% CI +1.5 to +4.4, fixed effects model, p < 0.001). Progesterone elevation on the day of hCG administration was associated with a significantly decreased probability of clinical pregnancy per cycle (-9%, 95% CI -17 to -2, fixed model effects, p). In conclusion, in patients treated with GnRH antagonists and gonadotrophins, progesterone elevation on the day of hCG administration is significantly associated with a lower probability of clinical pregnancy.


Cancer Letters | 2003

Methylenetetrahydrofolate reductase polymorphism C677T is not associated to the risk of cervical dysplasia

Alexandros Lambropoulos; Theodoros Agorastos; Z.J. Foka; Sofia Chrisafi; Theodoros C. Constantinidis; J. Bontis; Alexandros Kotsis

The aim of the study was to explore a possible association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and cervical neoplasia. A total of 229 women were subjected to cytologic and colposcopic evaluation. Ninety-one of them were found to be normal, and served as the control group, while the other 138 of them had present or past histologically proven cervical pathology (patients group). All patients and controls were investigated for the MTHFR C677T polymorphism. Statistical analysis between the groups of cases with cervical intraepithelial neoplasia or invasive cervical cancer and the control group did not reveal any statistically significant difference in the frequency of the MTHFR C677T polymorphism.


Journal of Maternal-fetal & Neonatal Medicine | 2002

Factor V Leiden and prothrombin G20210A mutations in pregnancies with adverse outcome

Theodoros Agorastos; A. Karavida; Alexandros Lambropoulos; Theodoros C. Constantinidis; S. Tzitzimikas; Sofia Chrisafi; H. Saravelos; Dimitrios Vavilis; Alexandros Kotsis; J. Bontis

Background: Inherited thrombophilia has been associated with obstetric complications through mechanisms that are not yet fully elucidated. The aim of this study was to investigate the relationship between specific obstetric adverse outcomes and factor V Leiden and prothrombin G20210A mutations. Methods: Forty-five women with adverse pregnancy outcome defined as severe pre-eclampsia, abruptio placentae, intrauterine growth restriction and stillbirth, were tested for factor V Leiden and prothrombin G20210A mutations. The control group comprised 100 women with at least one normal pregnancy and no history of thrombosis. Results: Overall, 13 women with one or more of the above-mentioned pregnancy complications (28%) had either thrombophilic mutation, as compared with six in the control group (6%) (p < 0.001, odds ratio (OR) 6.1; 95% confidence interval (CI) 1.9-20). The factor V Leiden mutation was detected in ten of the women with complicated pregnancies (22%) and in four of the controls (4%) (p < 0.001, OR 6.6; 95% CI 1.7-27.2). The prothrombin G20210A mutation was detected in three women in the group with complications (6%) and in two of the controls (2%) (p = 0.17, OR 3.4; 95% CI 0.4-30.5). Compared to controls, the prevalence of the factor V Leiden mutation was significantly higher in the subgroups of severe pre-eclampsia, abruptio placentae and fetal growth restriction. The prevalence of the prothrombin G20210A mutation does not appear to be significantly different from that in the controls in any of the groups studied. Conclusions: Our data suggest that inherited thrombophilia, and specifically the factor V Leiden mutation, may be associated with adverse pregnancy outcome. The role of the prothrombin G20210A mutation remains to be elucidated.


Acta Obstetricia et Gynecologica Scandinavica | 2007

Pregnancy and oral health: utilisation of dental services during pregnancy in northern Greece.

Konstantinos Dinas; Vassilios Achyropoulos; Emmanouel Hatzipantelis; Georgios Mavromatidis; Leonidas Zepiridis; Theodoros Theodoridis; Dimitrios Dovas; Tantanasis T; Fotios Goutzioulis; J. Bontis

Background. Recent studies have shown that gingivitis and periodontal infection during pregnancy represent an independent risk factor for pre‐term birth. However, little is known about the prevalence and correlates of dental attendance during pregnancy. Methods. During the first 3 days postpartum, an anonymous questionnaire was administered to 425 women in order to explore their dental condition and utilisation of dental health services during pregnancy, as well as their perceptions on the potential associations between dental care during pregnancy and pregnancy outcomes. Results. Almost half of the respondents (46.8%) reported symptoms of gingivitis during their pregnancy. Pregnancy gingivitis was independently associated with non‐Greek ethnicity (p = 0.008), multiparity versus primiparity (p<0.005), lower economic class versus middle and upper classes (p = 0.001), and the lack of routine primary dental care (p = 0.005). Some 27.3% reported a visit to the dentist during their pregnancy. The majority (72.2%) believed that dental treatment during pregnancy might have a negative affect on pregnancy outcome. The presence of pregnancy gingivitis and the belief that dental treatment during pregnancy is safe were both independently associated with visiting a dentist during pregnancy (p<0.0005 for both). Conclusions. Despite the increased prevalence of dental problems among pregnant women, few women seek dental services in this population, which can be primarily attributed to womens erroneous beliefs regarding the safety of dental examination. Therefore, there is an imperative need to offer oral health education and develop preventive programs for women of reproductive age.


Gynecologic and Obstetric Investigation | 2004

Endometriotic Uterocutaneous Fistula after Cesarean Section

K. Dragoumis; Themistoklis Mikos; Menelaos Zafrakas; E. Assimakopoulos; Panagiotis Stamatopoulos; J. Bontis

Endometriosis outside the pelvis is rare and most cases occur in surgical scars after operations involving the female genital tract. Fistulae involving the uterus are also very rare, usually being the result of postpartum and postoperative complications. In the present report, a case of a 44-year-old patient with an endometriotic uterocutaneous fistula is described. The patient presented 6 years after her fourth cesarean section with a painful nodule on the cesarean scar, which was bleeding during menstruation. The lesion extended to the uterine fundus, connecting the endometrial cavity with the skin. This is merely the second case of a uterocutaneous fistula to be reported in the literature and the first case developed on grounds of endometriosis.


Fertility and Sterility | 2001

Ambiguous genitalia, 45,X/46,XY mosaic karyotype, and Y chromosome microdeletions in a 17-year-old man

J. Papadimas; Dimitrios G. Goulis; Chariklia Giannouli; Papanicolaou A; Basil C. Tarlatzis; J. Bontis

OBJECTIVE To describe clinical and laboratory features of a patient with 45,X/46,XY mosaic karyotype and Y chromosome microdeletions and to discuss the diagnostic problems in his management. DESIGN Case report. SETTING University department. PATIENT(S) A 17-year-old man with ambiguous genitalia, 45,X/46,XY mosaic karyotype, and Y chromosome microdeletions. INTERVENTION(S) Testicular ultrasonography, karyotype, open testicular biopsy, polymerase chain reaction (PCR) screening for cystic fibrosis, PCR screening for Y chromosome microdeletions in peripheral blood and testicular tissue, and reverse transcriptase PCR in testicular tissue for Y chromosome microdeletions. MAIN OUTCOME MEASURE(S) Avoidance of dissemination of testicular cancer. RESULT(S) The patient was referred for bilateral orchiectomy. CONCLUSION(S) 45,X/46,XY mosaic karyotype is associated with a broad spectrum of phenotypes that includes female with Turner syndrome, male with mixed gonadal dysgenesis, male pseudohermaphroditism, and apparently normal male. Microdeletions of the long arm of the Y chromosome may be associated with Y chromosomal instability, leading to formation of 45,X cell lines. 45,X/46,XY males carry an increased risk for gonadal tumors and must be followed closely.


Fertility and Sterility | 1997

Therapeutic approach of immotile cilia syndrome by intracytoplasmic sperm injection: a case report

J. Papadimas; Basil C. Tarlatzis; Helen Bili; Tasos Sotiriadis; Kokona Koliakou; J. Bontis; S. Mantalenakis

OBJECTIVE To present a case of immotile cilia syndrome, a very rare cause of male infertility and to evaluate the role of the recently suggested treatment by intracytoplasmic sperm injection (ICSI). DESIGN Case report. SETTING Tertiary-care academic hospital. PATIENT(S) One man with immotile cilia syndrome, showing no motile spermatozoa despite normal morphology and viability. INTERVENTION(S) The patients partner underwent two cycles with IVF of the oocytes achieved by ICSI. MAIN OUTCOME MEASURE(S) Evaluation of ICSI procedure in cases of immotile cilia syndrome. RESULT(S) Thirty-three percent of the oocytes were fertilized and subsequently divided enabling ET in both cycles. CONCLUSION(S) Intracytoplasmic sperm injection seems to represent a promising approach to the problem of infertility in men with immotile cilia syndrome.


European Journal of Cancer Prevention | 2004

Cervical human papillomavirus infection in women attending gynaecological outpatient clinics in northern Greece.

Theodoros Agorastos; K Dinas; B Lioveras; F X Bosch; J R Kornegay; J. Bontis; S Sanjose

Human papillomavirus (HPV) is the necessary cause for the development of invasive cervical cancer. Identification of HPV determinants may contribute to the targeting of high-risk groups for cervical cancer. The study was aimed at estimating HPV prevalence and its determinants among 1296 women attending six gynaecological outpatient clinics in northern Greece. Information was available through personal interview and the study of cervical exfoliated cells. HPV DNA was detected by reverse line-blot polymerase chain reaction using the L1 primers PGMY09/11. The overall HPV prevalence was 2.5%. After controlling for potential confounders, the two independent risk factors associated with an increased prevalence were young age and parity. The prevalence odds ratio (POR) for those younger than 27 years against those older than 42 years was 5.31 (95% confidence interval (CI)=1.53–18.44) and the POR for nulliparous women compared with women with two or more children was 4.15 (95% CI=1.35–12.76). HPV was present in 10 of 12 women with low-grade cervical intraepithelial lesions (CIN) (83.3%) and in 3 of 4 with high-grade CIN (75%). The prevalence of genital HPV infections in the study population was among the lowest ever reported internationally.


Cases Journal | 2009

Laparoscopic management of mesenteric cyst: a case report

Theodoros Theodoridis; Leonidas Zepiridis; Dimitrios Athanatos; Filippos Tzevelekis; Diamantis Kellartzis; J. Bontis

Mesenteric cysts are rare intra-abdominal lesions with variable clinical symptoms and signs that make pre-operative diagnosis difficult. Optimal treatment is surgical excision of the cyst with laparotomy or laparoscopy. We present a case of mesenteric cyst that was misdiagnosed as para-ovarian cyst and managed laparoscopically by gynaecologists.

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Basil C. Tarlatzis

Aristotle University of Thessaloniki

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Menelaos Zafrakas

Aristotle University of Thessaloniki

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Theodoros Agorastos

Aristotle University of Thessaloniki

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S. Mantalenakis

Aristotle University of Thessaloniki

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J. Papadimas

Aristotle University of Thessaloniki

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Themistoklis Mikos

Aristotle University of Thessaloniki

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Apostolos Athanasiadis

Aristotle University of Thessaloniki

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Grigoris F. Grimbizis

Aristotle University of Thessaloniki

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Theodoros Theodoridis

Aristotle University of Thessaloniki

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E. Assimakopoulos

Aristotle University of Thessaloniki

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