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Dive into the research topics where Mehmet Simsek is active.

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Featured researches published by Mehmet Simsek.


Biological Trace Element Research | 2003

COMPARISON OF SERUM COPPER, ZINC, CALCIUM, AND MAGNESIUM LEVELS IN PREECLAMPTIC AND HEALTHY PREGNANT WOMEN

Selahattin Kumru; Suleyman Aydin; Mehmet Simsek; Kazim Sahin; Mehmet Yaman; Gul Ay

Deficient or excessive levels of blood trace elements can be an adverse factor in human and animal pregnancy. The aim of this study was to investigate possible differences in the levels of serum magnesium, calcium, copper, and zinc in preeclamptic and healthy pregnant women. Samples were collected from 30 preeclamptic (PE) and 30 healthy pregnant (HP) women. The serum copper concentration was significantly lower in the PE group by 68% (p<0.0001) when compared to the healthy controls. The serum zinc and calcium were 43% and 10% lower in the PE women, respectively (both with p<0.0001), whereas the magnesium concentration showed nonsignificant differences between the two groups. Measurement of these elements may be useful for the early diagnosis of a preeclamptic condition.


Clinical Biochemistry | 2002

The changes of trace elements, malondialdehyde levels and superoxide dismutase activities in pregnancy with or without preeclampsia.

Necip Ilhan; Nevin Ilhan; Mehmet Simsek

OBJECTIVES Increased free radical activity and lipid peroxidation may be implicated in the pathogenesis of preeclampsia. This study was initiated to assess antioxidant enzyme and trace metalss status in preeclampsia. DESIGN AND METHODS The comparison was made between the pregnant women with or without preeclampsia and healthy controls in this study. Samples were obtained from 24 normal nonpregnant (controls), 30 normal pregnant and 21 preeclamptic women in the third trimester. Lipid peroxidation end product, malondialdehyde (MDA), free radical scavenging enzyme activity, superoxide dismutase (SOD) and serum zinc (Zn), copper (Cu) levels were measured in either plasma/serum or erythrocytes of patients. Data were analyzed statistically using Students t-test. RESULTS In the preeclamptic group malondialdehyde, Cu levels were significantly increased, while Zn and SOD levels were significantly decreased compared to normal control group and healthy pregnant women. CONCLUSIONS Our findings give support that radical scavenging SOD is consumed by the increased lipid peroxidation in preeclampsia. This data may indicate an involvement of free radicals in the pathophysiology of preeclampsia. This study suggests a relationship between increased MDA, Cu levels and decreased SOD, Zn levels in pregnancy and preeclampsia.


Reproductive Biomedicine Online | 2008

Treatment of symptomatic uterine leiomyoma with letrozole

Bilgin Gurates; Cem Parmaksiz; Gokhan S. Kilic; Husnu Celik; Selahattin Kumru; Mehmet Simsek

Uterine leiomyomas are the most common benign tumours of the female genital tract, often necessitating hysterectomy. The most common symptoms are dysmenorrhoea, menorrhagia, infertility and abortion. Ovarian hormones seem to play an essential role in pathogenesis, and deprivation of ovarian oestrogen causes leiomyomas to shrink significantly. The purpose of this study was to evaluate the effects of the non-steroidal aromatase inhibitor letrozole on uterine leiomyomas and on bone metabolism. A prospective, open clinical trial was conducted in a university-based hospital. Sixteen premenopausal women with symptomatic uterine leiomyomas were treated with letrozole 5 mg/day orally for 3 months. The main outcome measures of uterine and uterine leiomyoma sizes, serum FSH, LH, oestradiol concentrations, ovarian volumes and myoma-related symptoms were noted at baselines and once a month during treatment. Lumbar spine bone mineral density and biochemical markers of bone metabolism were studied at the beginning and at the end of 3 months. Letrozole significantly decreased uterine leiomyoma sizes (P < 0.01) and promptly benefited women with heavy menstrual bleeding associated with leiomyomas without changing bone mineral density. Aromatase inhibitors may represent a new generation of medications for the treatment of leiomyoma and associated symptoms. Larger clinical trials are needed, however, to fully evaluate their safety and efficacy.


Hypertension in Pregnancy | 2005

Oxidant-Antioxidant System Changes Relative to Placental-Umbilical Pathology in Patients with Preeclampsia

Esra Bulgan Kilicdag; Gul Ay; Aygen Celik; Bilal Ustundag; Ibrahim Hanifi Ozercan; Mehmet Simsek

Objective. It is speculated that lipid peroxidation is responsible for the pathologic changes that occur in the uteroplacental vasculature of women with preeclampsia. The aim was to investigate this proposed relationship. Materials and Methods. The prospective study involved 90 pregnant women. Thirty had mild preeclampsia, 30 had severe preeclampsia, and 30 were healthy pregnant women (controls). The data collected for each case were umbilical cord and placental pathologies, plasma malondialdehyde (MDA) level, and levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in erythrocytes. Group findings were compared. Results. The mean MDA level in the severe preeclampsia group was higher than the corresponding findings in the mild preeclampsia and control groups (p < 0.001 for both). Also, the MDA level in the mild preeclampsia group was significantly higher than was the control level (p < 0.001). The mean SOD activity level in the severe preeclampsia group was lower than the corresponding results in the mild preeclampsia and control groups (p < 0.001 for both). The mean GSH-Px levels in the mild and severe preeclampsia groups were both significantly lower than was the corresponding finding in the control group (p < 0.01). Compared to the control group, both preeclampsia groups had significantly higher frequencies for placental infarction, villous fibrosis, increased numbers of syncytial nodes, and thickening of vessel walls and lumen obliteration (p < 0.001 for all). Villous fibrinoid necrosis, perivillous fibrosis, and increased villous vascularization were also significantly more frequent in both preeclampsia groups than in the control group, but the differences for these parameters were smaller (p < 0.01 for all). Examination of the samples from the placental ends of the umbilical cords revealed significantly higher frequencies of endothelial irregularity, endothelial shedding, and basal membrane thickening in both preeclampsia groups than in those of the control group (p < 0.001). The same findings were noted in the middle sections of the cords (p < 0.001). At the fetal ends of the umbilical cords, both preeclampsia groups had higher frequencies of endothelial irregularity than did the control group (p < 0.001); however, the frequencies of the more severe pathologic findings (endothelial shedding, basal membrane thickening) in the three groups were similar. Conclusion. The frequencies of pathologic changes in the placenta and umbilical vessels of women with preeclampsia parallel the severity of this condition. These changes also parallel plasma levels of MDA, the end product of lipid peroxidation.


Journal of Obstetrics and Gynaecology Research | 2008

Heterotopic triplet pregnancy (twin tubal) in a natural cycle with tubal rupture: Case report and review of the literature

Tayup Simsek; Askın Dogan; Mehmet Simsek; Elif Pestereli

The incidence of heterotopic/ectopic pregnancy has risen in recent years, largely due to more frequent use of ovulatory medicine and increased incidence of pelvic inflammatory disease. In a natural cycle, it is a very rare event. Most heterotopic/ectopic pregnancies are localized in the uterine tube and, usually, it is diagnosed when symptoms develop. We report the case of a 37 year‐old, gravida 2, para 0, abortion 1 woman with no known risk factors for heterotopic pregnancy. The patient attended the emergency department because of acute abdominal pain. She was evaluated in our department and a heterotopic twin pregnancy in the tube was diagnosed by transvaginal sonography. Intrauterine pregnancy with positive fetal cardiac activity at 9 weeks of gestation according to crown‐rump length measurement was detected. Laparotomy was carried out because of acute abdominal syndrome. Right ruptured tubal ectopic/heterotopic pregnancy and hemoperitoneum were diagnosed. Right salpingectomy was carried out. Pathology revealed monochorionic twin tubal pregnancy. In a review of the literature, this is first case of twin tubal pregnancy in one uterine tube. In conclusion, heterotopic pregnancy in twin form in the uterine tube is possible in natural cycles. Intrauterine pregnancy does not exclude extrauterine pregnancy in natural cycles.


Journal of Obstetrics and Gynaecology Research | 2007

Effects of hormone replacement therapy on bone mineral density in Turkish patients with or without COL1A1 Sp1 binding site polymorphism

Mehmet Simsek; Zafer Cetin; Turker Bilgen; Omur Taskin; Guven Luleci; Ibrahim Keser

Aim:  To evaluate the effects of hormone replacement therapy (HRT) on bone mineral density (BMD) in patients with or without COL1A1 Sp1 binding site polymorphism.


Journal of Maternal-fetal & Neonatal Medicine | 2014

Plasma IL-17, IL-35, interferon-γ, SOCS3 and TGF-β levels in pregnant women with preeclampsia, and their relation with severity of disease

Zehra Sema Ozkan; Mehmet Simsek; Fulya Ilhan; Derya Deveci; Ahmet Godekmerdan; Ekrem Sapmaz

Abstract Objective: To research the hypothesis of preeclampsia (PE) is associated with increased systemic inflammatory responses of Th1-type as well as decreased Th2-type responses; we evaluated the maternal plasma levels of IFN-gamma, TNF-alpha, TGF-beta, IL-4, IL-6, IL-10, IL-17, IL-35 and SOCS3 in preeclamptic and healthy pregnants. Methods: This study was conducted with 40 preeclamptic (study group) and 40 normotensive pregnant (control) women in third trimester when they were admitted to the labor and delivery unit. The extracted maternal plasma samples were assayed by an enzyme-linked immunosorbent assay. Statistical analysis was performed by SPSS 16.0 version. Results: While IFN-gamma and TGF-beta levels of preeclamptic women were significantly higher (p < 0.01), IL-35 and IL-17 levels of preeclamptic women were significantly lower (p < 0.01) than those of controls. The ratios of IFN-gamma/IL-10, IFN-gamma/IL-6, IFN-gamma/IL-4 were significantly high and ratio of IL-35/IL-17 was significantly low in the PE group compared to those in the control group. Maternal plasma SOCS3 levels showed negative correlation with blood pressure and proteinuria severity, but none of the cytokines showed influence on blood pressure and proteinuria after adjusting for maternal and gestational age. Conclusions: Increased IFN-gamma/TGF-beta production and reduced IL-35/IL-17/SOCS3 production in preeclamptic women may lead to less cytokine inhibitory activity in PE, which may account for the increased proteinuria and blood pressure in PE.


Journal of Reproductive Immunology | 2014

What is the impact of Th1/Th2 ratio, SOCS3, IL17, and IL35 levels in unexplained infertility?

Zehra Sema Ozkan; Derya Deveci; Banu Kumbak; Mehmet Simsek; Fulya Ilhan; Samet Sekercioglu; Ekrem Sapmaz

Implantation necessitates complex interactions among the developing embryo, decidualizing endometrium, and developing maternal immune tolerance and/or alterations in cellular and humoral immune responses. Overstimulation of T helper 1 (Th1) or Th2 cytokines in systemic and local environments, alterations of the prevalence of IL17 and regulatory T cell (Treg) cytokines have also been suggested to contribute to the pathogenesis of implantation failure. We aimed to investigate the plasma levels of IL4, IL6, IL10, TNFα, IFNγ, TGFβ, IL17, IL35, and SOCS3 in infertile and fertile women. This case-control study was conducted with 80 women suffering from unexplained infertility and 40 fertile women. Peripheral venous blood samples were drawn on day 21 of the menstrual cycle. The extracted plasma samples were assayed by an enzyme linked immunosorbent assay. Statistical analysis was performed using SPSS version 16.0. Our main findings were as follows: despite the significantly high IL17 and IL35 plasma levels of infertile women, IL35/IL17 ratio was significantly lower in the infertile group compared with that in the fertile group; SOCS3 plasma levels showed an inverse relation with plasma levels of all cytokines except IL35; increased plasma IL17 levels (>3.42 pg/mL) have a negative impact on fertility; TNFα/IL10, IFNγ/IL10, IFNγ/IL6, and IFNγ/IL4 ratios were significantly higher in infertile group compared with those in the fertile group. It is not possible to show the major immunological factor(s) of unexplained infertility, but our findings point out that the decreased suppressor activity of the immune system may play a role in implantation failure.


Journal of Maternal-fetal & Neonatal Medicine | 2015

What is the impact of SOCS3, IL-35 and IL17 in immune pathogenesis of recurrent pregnancy loss?

Zehra Sema Ozkan; Derya Deveci; Mehmet Simsek; Fulya Ilhan; Ali Risvanli; Ekrem Sapmaz

Abstract Objective: To investigate the plasma levels of interleukin-4 (IL-4), IL-6, IL-10, tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta), IL-17, IL-35 and suppressor of cytokine signaling 3 (SOCS3) in the women with history of idiopathic recurrent pregnancy loss (RPL) and in the fertile controls. Methods: This study was conducted with 60 idiopathic RPL cases and 40 age-matched fertile controls. Mid-follicular plasma levels of IL-17, IFN-gamma, TNF-alpha, TGF-beta, IL-6, IL-4, IL-10, SOCS3 and IL-35 were assayed by an enzyme linked immunosorbent assay. Results: The mean age of RPL and control cases were 31.6 ± 0.6 and 32.1 ± 0.7 years, respectively. While plasma IL-35 and SOCS3 levels of RPL group were significantly lower than that of the control group; IFN-gamma, TNF-alpha, IL-4, IL-6, IL-10, IL-17 and TGF-beta levels of RPL group were significantly higher than that of the control group. The comparison of cytokine ratios between RPL and control groups indicated significantly high TNF-alpha/IL-10, TNF-alpha/IL-4, IFN-gamma/IL-10, IFN-gamma/IL-6 and IFN-gamma/IL-4 ratios in the RPL group. IL-35/IL-17 ratio was significantly low in the RPL group compared to that in the control group. Overstimulation of TNF-alpha presented moderate influence on recurrent miscarriage risk. Conclusion: Decreased SOCS3 and IL-35 plasma levels and increased Th1/Th2 cytokine ratios in RPL cases pointed out the supression of anti-inflammatory process and this supression might play an important role in the pathogenesis of idiopathic RPL.


The European Journal of Contraception & Reproductive Health Care | 2011

Heterotopic pregnancy following bilateral tubal ligation: Case report

Banu Kumbak; Zehra Sema Ozkan; Mehmet Simsek

ABSTRACT Case report A 38-year-old woman presented, one year after bilateral tubal ligation, with vaginal bleeding, vomiting, and stupor. Ten days earlier, she had submitted to a dilatation and curettage for an unexpected intrauterine pregnancy. At the time of this presentation there was rebound tenderness and guarding on abdominal examination, and a 2.5 cm right adnexal mass was detected on transvaginal ultrasound together with free fluid in the pelvis. The serum level of beta-hCG was 8522 mIU/ml. At laparoscopy a right tubal pregnancy and a large haematocele in the pouch of Douglas were detected. A right salpingectomy and a bipolar electrocoagulation of the left tubo-cornual junction were performed laparoscopically. Conclusion Pregnancy after tubal sterilisation may be heterotopic and this possibility should be considered in the differential diagnosis.

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Omur Taskin

Baylor College of Medicine

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