PubMed Health⌕ Search

Biomedical subjects

H van der Ven

Publications and source records attributed to H van der Ven.

At least 19 recordsLinked to original sources

Escherichia coli derived factors modulate human granulosa cell steroidogenesis.

AIM: In order to identify bacterial compounds which directly affect granulosa cell steroidogenesis, the effect of culture-supernatants and extracts from Escherichia coli were tested in an in vitro granulosa cell culture model. METHODS: Samples were drawn from the culture-supernatant of E. coli ATCC25922 cultured in Luria-broth medium. Bacterial extract was prepared by incubation of freshly harvested bacteria in buffer. The bacterial culture-supernatants and extracts were added to human granulosa cells in culture. The granulosa cells collected from the follicular aspirates from women undergoing in-vitro fertilization were cultured for 17-53 h and progesterone or oestradiol was assayed in the spent culture medium. RESULTS: The E. coli culture-supernatant stimulated the basal granulosa cell progesterone production demonstrating its maximum activity reached after 200-240 min of bacterial growth. The heat denaturated bacterial extract as well as its low-molecular-weight fraction (<10 kDa) stimulated both the basal and the hCG-stimulated progesterone production; the oestradiol production was slightly inhibited. Stimulation of progesterone production was time dependent increasing from 125 +/- 18% of control within the first 3 h to 205 +/- 35% within 17-53 h. The high-molecular-weight fraction (>30 kDa) of the bacterial extract inhibited progesterone production. The inhibitory activity was significantly diminished by heat denaturation. CONCLUSIONS: The present study demonstrates the existence of various compounds which are secreted by E. coli and could also be extracted out of E. coli bacteria. These bacterial compounds modulate ovarian steroidogenesis. Further studies are needed to clarify how far these compounds contribute to menstrual disturbance observed in chronic pelvic inflammation.

Adult↗

Aseptic technology of vitrification of human pronuclear oocytes using open-pulled straws.

BACKGROUND: The aim of this study was to compare the viability of human pronuclear oocytes subjected to vitrification using cooling by direct submerging of open-pulled straws in liquid nitrogen versus vitrification by cooling of open-pulled straws located inside a closed 0.5 ml straw (aseptic system). METHODS: Two- and three-pronuclei stage oocytes (n=114) were cryopreserved in super-open-pulled straws by vitrification in 20% ethylene glycol +20% dimethylsulphoxide (DMSO) + osmotic active and neutral non-permeable cryoprotectants with a four-step exposure in 20, 33, 50 and 100% vitrification solution for 2, 1 and 1 min, and 30-50 s, respectively at room temperature, and plunging into liquid nitrogen. Oocytes of group 1 (n=42) were rapidly cooled at a speed of 20,000 degrees C/min by direct plunging of open-pulled straws into liquid nitrogen. Oocytes of group 2 (n=44) were first located in 0.5 ml straws, which were closed at both sides by metal balls, and then plunged into liquid nitrogen. This method resulted in a cooling speed of 200 degrees C/min. For both groups, oocytes were thawed rapidly at a speed of 20 000 degrees C/min using an identical protocol. Oocytes subsequently were expelled into a graded series of sucrose solutions (1.0, 0.75, 0.5, 0.25 and 0.12 mol/l) at 2.5 min intervals. RESULTS: Oocyte development up to expanded blastocyst stage after in vitro culture was 15% in group 1, 14% in group 2 and 29% in an untreated control group. CONCLUSION: The deposition of human pronuclear oocytes in open-pulled straws which are placed inside a hermetically closed container guarantees a complete isolation of oocytes from liquid nitrogen and avoids potential contamination by pathogenic microorganisms. The combination of direct plunging of this container into liquid nitrogen and rapid warming makes this process as efficient as conventional vitrification.

Asepsis↗

Oxytocin receptor gene expression of estrogen-stimulated human myometrium in extracorporeally perfused non-pregnant uteri.

Oxytocin (OT) and the oxytocin receptor (OTR) seem to be less important for uterine contractility-associated disorders of the non-pregnant uterus compared to the pregnant uterus. In the present study, we investigated the mutual dependence of OTR, OT and 17beta-estradiol (E(2)) with regard to the localization of OTR in the non-pregnant uterus. Utilizing our established model for extracorporeal perfusion of the human uterus, we perfused 15 human uteri for 27 h under physiological conditions without oestradiol (group A, n = 5) or with high E(2) stimulation (group B, n = 5) followed by OT stimulation for both groups during the last 3 h of the experiment. Negative controls (n = 5) remained in perfusions for 27 h without any further hormone treatment. Gene expression of the myometrial OTR in both groups was compared using reverse transcriptase triple primer PCR. Stimulation with E(2) and OT led to significantly higher OTR gene expression than stimulation with OT alone. We also showed that concentrations of OTR transcripts increase from the lower uterine segment to the uterine fundus. However, maximum OTR levels of the uterine fundus in group B did not reach concentrations of specimens of third trimester of pregnancy which were used as positive controls. We conclude that our experimental model simulates a situation similiarly to the stimulated non-pregnant uterus in the therapeutic concepts of assisted reproduction. The data presented demonstrate that the dynamics of OTR expression can be modulated by stimulation with E(2) and OT, not only in the pregnant but also in the non-pregnant uterus.

Adult↗

Previous miscarriages influence IVF and intracytoplasmatic sperm injection pregnancy outcome.

Previous conceptions are one predictor for the outcome of assisted reproductive technology procedures. Approximately 18-34% of clinical pregnancies following assisted reproduction procedures result in spontaneous abortion. The risk of such pregnancy loss is believed to increase with women's age, previous miscarriages and use of frozen-thawed embryos. This study analyses German IVF Registry data to examine the impact of previous miscarriages on the outcome of assisted reproduction procedures. The data set consists of a total of 174,909 assisted reproduction procedures performed between January 1998 and December 2000. Multiple logistic regression is used to assess the correlation between women's age, spousal/partner change, and infertility diagnosis. It is demonstrated that any previous miscarriage will increase the treatment-dependent miscarriage rate in assisted reproduction procedures. A significantly higher impact is shown for one previous miscarriage achieved by assisted reproduction procedures compared with spontaneous conception. Partner change is shown to have no specific impact on the treatment dependent miscarriage rate, whereas a statistically significant increase in miscarriages in all assisted reproduction procedures was found among women older than 34 years of age. Overall, the highest rate of treatment-dependent miscarriages was seen in assisted reproduction procedures with cryopreserved embryo transfer.

Abortion, Spontaneous↗

Studies on the efficacy of different adjuvants in live stock specific bacterial vaccines for turkeys against Bordetella infection and onset of antibody titers in respect to the age of the turkey poults.

For evaluating the influence of the age of the vaccinated birds on the development of antibodies, five groups of turkey poults were inoculated subcutaneously at day 1, 7, 10, 14 and 21 of life with vaccine containing inactivated Bordetella avium and Freund's incomplete adjuvant. No matter which vaccine schedule was used, serum antibodies with the ELISA were first detected at the 28th day of life and increased continuously until the 49th day, when it exhibited either a peak or a plateau. Aluminium hydroxide, Freund's complete and incomplete adjuvant and a mineral oil-arlacel-tween-mixture being permitted adjuvants (appendix II EWG 2377/90) and the adjuvant Gerbu 100 were evaluated for their suitability. Turkeys were vaccinated at the age of three weeks and examined clinically as well as serologically up to the 11th week. Humoral antibodies were detected quantitatively using an ELISA for IgG and a microagglutination test for IgM and qualitatively using immunodiffusion. The damage at the application site was rated by measurement of the swelling of the tissue. In the 10th week, the animals were infected with the agent for challenge. The serological examination for IgG antibodies in the ELISA both treatments with Freund's adjuvants resulted in high titers, which differed significantly from the unvaccinated control after 21 days. IgM could be detected from day 7 onwards in all vaccinated groups and showed the highest titers when aluminium hydroxide was used as adjuvant. In the immunodiffusion assay, precipitating antibodies could be found from the first week after vaccination onwards. There was no correlation between the occurrence of precipitating antibodies and ELISA titers. The measurements of the swelling of the tissue in the beginning showed the largest swellings in the animals injected with Freund's incomplete adjuvant and differed significantly from the unvaccinated control. In the 10th week, the animals were infected with Bordetella avium for challenge. In comparison to the unvaccinated animals, all vaccinated turkeys, no matter which adjuvant was used, showed a distinct and significant reduction of the reisolation rate.

Adjuvants, Immunologic↗

Three-dimensional power Doppler ultrasound of the subendometrial blood flow under the administration of a contrast agent (Levovist).

METHODS: Based on the results from 42 IVF patients on the day of oocyte aspiration, our study tested the hypothesis that 3-D Doppler ultrasound of the endometrium supported by a contrast agent possesses advantages over a conventional 3-D Doppler ultrasound examination. We also determined whether the subendometrial blood flow indices measured under continuous infusion of Levovist (Schering, Berlin, Germany) were an indicator of a successful implantation. RESULTS: It was demonstrated that, after the administration of Levovist, all subendometrial blood flow parameters (e.g., vascularization index [VI: 8.82+/-16.64], flow index [FI: 35.67+/-9.33], and vascularization flow index [VFI: 3.99+/-8.80]) were significantly higher than without the contrast agent ( p<0.001; VI: 3.09+/-7.11; FI: 29.13+/-14.26; VFI: 1.35+/-3.31). However, no significant differences between blood flow with contrast agent and pregnancy rate were found. CONCLUSION: In summary, quantitative 3-D Doppler ultrasound employing Levovist (Schering, Berlin, Germany) is significantly more sensitive when compared to conventional 3-D Doppler examination. For the first time this was demonstrated on 42 IVF patients on the day of oocyte aspiration. However, no correlation with outcome of the IVF-treatment could be found.

Adult↗

Easy and effective--web-based information systems designed and maintained by physicians: experience with two gynecological projects.

It is well established that medical information sources develop continuously from printed media to digital online sources. To demonstrate effectiveness and feasibility of decentralized performed web-based information sources for health professionals, two projects are described. The information platform of the German Working Group for Information Technologies in Gynecology and Obstetrics (AIG) and the information source concerning the German Registry for in vitro fertilization (DIR) were implemented using ordinary software and standard computer equipment. Only minimal resources and training were necessary to perform safe and reliable web-based information sources with a high correlation of effectiveness in costs and time exposure.

Data Collection↗

Reproductive dysfunction in women with epilepsy: recommendations for evaluation and management.

BACKGROUND: Epilepsy is commonly associated with reproductive endocrine disorders. These include polycystic ovary syndrome (PCOS), isolated components of this syndrome such as polycystic ovaries, hyperandrogenaemia, hypothalamic amenorrhoea, and functional hyperprolactinaemia. OBJECTIVE: To summarise the currently known relations between epilepsy and reproductive endocrine disorders. METHODS: A review of clinical experience and published reports. RESULTS: The most likely explanations for endocrine disorders related to epilepsy or antiepileptic drugs are: (1) a direct influence of the epileptogenic lesion, epilepsy, or antiepileptic drugs on the endocrine control centres in the brain; (2) the effects of antiepileptic drugs on peripheral endocrine glands; (3) the effects of antiepileptic drugs on the metabolism of hormones and binding proteins; and (4) secondary endocrine complications of antiepileptic drug related weight changes or changes of insulin sensitivity. Regular monitoring of reproductive function at visits is recommended, including questioning about menstrual disorders, fertility, weight, hirsutism, and galactorrhoea. Particular attention should be paid to patients on valproate and obese patients or those experiencing significant weight gain. Single abnormal laboratory or imaging findings without symptoms may not constitute a clinically relevant endocrine disorder. However, patients with these kinds of abnormalities should be monitored to detect the possible development of a symptomatic disorder associated with, for example, menstrual disorders or fertility problems. CONCLUSIONS: If a reproductive endocrine disorder is found, antiepileptic drug treatment should be reviewed to ensure that it is correct for the particular seizure type and that it is not contributing to the endocrine problem. The possible benefits of a change in treatment must be balanced against seizure control and the cumulative side effect of alternative agents.

Anticonvulsants↗

Oral contraceptives moderately effect bone resorption markers and serum-soluble interleukin-6 receptor concentrations.

This study investigated the effect of ethinylestradiol(EE2)-containing oral contraceptives on mineral and bone metabolism and on serum soluble-interleukin-6-receptor (sIL-6R) during the menstrual cycle. Twelve women, aged 24.3 +/- 2.9 years, were examined. Blood and 24-hour and fasting urine samples were obtained during one menstrual cycle between cycle day 3-5 (t(1)), cycle day 10-12 (t(2)), cycle day 24-26 (t(3)), and again on day 3-5 of the next cycle (t(4)). EE2 intake was 0 mg at t(1), 30 mg at t(2), 30 mg at t(3) and 0 mg at t(4). Fasting renal phosphorus and calcium excretions were slightly reduced at t(2) and t(3) compared with t(1) and t(4) (P < 0.05-0.001). Moreover, renal excretion of the bone resorption marker C-Teleopeptide was at t(3) reduced by 26% compared with t(1)(P < 0.01) and by 13% compared with t(4)(P > 0.05). Fasting sIL-6R levels were 16.5% lower at t(2) and 12% lower at t(3) than at t(4) (P < 0.01 and P < 0.05). sIL-6R was correlated with total deoxypyridinoline excretion (r = +0.35; P < 0.05) and with fasting renal excretions of calcium (r = +0.36; P < 0.05) and phosphorus (r = +0.29; P < 0.05). In summary, our data suggest that in young women, cyclic monthly oral contraceptive intake is associated with small, but significant variations in bone resorption processes and in serum sIL-6R levels. Results are a further indication that monthly fluctuations of bone resorption in young women are mediated by sex hormones and that osteoclastic activity is stimulated by cytokines in vivo.

Adult↗

The role of ovarian volume in an in vitro fertilization programme as assessed by 3D ultrasound.

The study was designed to investigate the role of ovarian volume, as assessed by three-dimensional (3D) sonography, in predicting conception in an in-vitro fertilization-embryo transfer (IVF-ET) programme. Transvaginal 3D sonography was performed in 152 cycles before initiation of ovarian stimulation (day 1) and on the day of oocyte retrieval. Ovarian volume showed no significant correlation with IVF outcome. On the contrary, all ovarian measurements were lower, albeit nonsignificantly, in the conception group. Fifteen patients (15/152, 9.9%) had a minimum unilateral ovarian volume of < or =3 mL (1 SD below the mean) on day 1 of the stimulation cycle. In this subgroup, the likelihood of conception was 6.7% (1/15) versus 21.9% (30/137) in patients with an initial minimum ovarian volume of >3 mL. This difference did not reach statistical significance. In both groups, cancellation rates due to poor ovarian response or lack of fertilization were similar. In conclusion, ovarian volumetry as assessed by three-dimensional ultrasound failed to predict conception in women undergoing IVF treatment.

Adult↗

Endometrial receptivity in an in vitro fertilization program as assessed by spiral artery blood flow, endometrial thickness, endometrial volume, and uterine artery blood flow.

OBJECTIVE: To investigate the role of sonographic parameters in assessing endometrial receptivity in an in vitro fertilization (IVF) program. DESIGN: Prospective clinical study. SETTING: University setting. PATIENT(S): One hundred thirty-five patients in our IVF program, selected prospectively on the day of oocyte retrieval. INTERVENTION(S): Transvaginal ultrasound examination was performed before oocyte collection. MAIN OUTCOME MEASURE(S): Association between implantation rate and spiral artery blood flow (primary outcome measure) and between implantation rate and endometrial measurements as well as uterine artery blood flow (secondary outcome measures). RESULT(S): Overall implantation rate was 23.7% per cycle. Subendometrial blood flow was detected in 113 (83.7%) cases, with pregnancy occurring in 21.2%. Mean spiral artery pulsatility index values were 1.12 +/- 0.28 and 1.21 +/- 0.27 for nonconception and conception cycles, respectively. Nondetectable spiral artery blood flow was not associated with a lower implantation rate. Neither endometrial thickness nor endometrial volume was correlated with the likelihood of successful implantation. Minimum endometrial thickness and volume associated with pregnancy were 6.9 mm and 1.59 mL, respectively. CONCLUSION(S): Neither Doppler sonography of the spiral or uterine arteries nor measurement of the endometrial thickness or volume allowed a reliable prediction of subsequent IVF outcome.

Arteries↗

Testicular sperm extraction in a patient with metachronous bilateral testicular cancer.

A new indication for testicular tissue cryopreservation is demonstrated in a patient with metachronous bilateral testicular tumours and azoospermia. At the age of 18 (1982) the patient underwent left orchidectomy and radical retroperitoneal lymphadenectomy for a testicular teratoma (pT1N0M0). Semen samples were not cryopreserved because of absence of motile spermatozoa after thawing. Seventeen years after the primary testicular cancer, a seminoma of the contralateral right testis was diagnosed (pT1N0M0). Since the patient was azoospermic, no semen samples could be cryopreserved. However, spermatozoa were detected in testicular biopsy material of the right testis and were cryopreserved for ICSI. Since all spermatozoa were dead after thawing, testicular sperm extraction (TESE) was performed in the remaining tissue samples at the time of ICSI treatment. Only spermatids could be extracted from frozen-thawed samples due to the inhomogeneous distribution of spermatogenic activity in the testicular tissue. Although one oocyte was fertilized with these spermatids, a clinical pregnancy was not achieved. Despite the disappointing results of ICSI in the couple presented here, this case report demonstrates that cryopreservation of testicular tissue and TESE should be considered in patients with bilateral testicular tumours and azoospermia, if frozen semen samples are not available.

Adolescent↗

Evaluation of pronuclear morphology as the only selection criterion for further embryo culture and transfer: results of a prospective multicentre study.

BACKGROUND: The aim was to study zygote evaluation based on pronuclear morphology under the German embryo protection law, according to which only a maximum of three zygotes are allowed to be cultured for embryo transfer. METHODS: In this prospective multicentre study, a total of 512 treatment cycles was performed at 10 centres, between November 1999 and October 2000. Zygotes were classified into seven patterns (0A, 0B and 1-5). Pattern 0A and 0B zygotes were preferentially used for further culture and transfer. RESULTS: Cycles with transfer of at least one embryo derived from pattern 0B, but not pattern 0A, resulted in significantly higher pregnancy (37.9%) and implantation rates (20.5%) compared with non-pattern 0B cycles (26.4 and 15.7%; P < 0.05 and P < 0.01 respectively). In younger patients (aged < or =35 years), significantly more 0B zygotes were available for transfer than in older patients (34.2 versus 25.8%; P < 0.005). CONCLUSIONS: From these data, it is concluded that evaluation of pronuclear morphology is beneficial, especially for countries with legal restrictions regarding embryo selection.

Adult↗

The HLA-G genotype is potentially associated with idiopathic recurrent spontaneous abortion.

The causes for recurrent spontaneous abortion (RSA) remain unknown in a large proportion of the cases. Human leukocyte antigen (HLA)-G and HLA-E are expressed on invasive trophoblast cells, and are supposed to confer to materno-fetal tolerance. A total of 14 different nucleotide sequences have been described for HLA-G, including one dysfunctional null allele (HLA-G*0105N), while five different sequences have been described for HLA-E. In this study, 78 RSA couples and 52 fertile controls were typed for HLA-G and HLA-E by direct sequencing or single strand conformational polymorphism (SSCP) respectively. The overall analysis showed no significant difference in allele frequencies for either HLA-G or HLA-E between the two groups. However, HLA-G allele frequencies in women who had suffered from five or more RSA differed significantly from fertile controls (P: = 0.001), and from women who had undergone three or four RSA (P: = 0.027). Detailed analysis demonstrated a significant increase in the proportion of the HLA-G alleles *01013 and *0105N in the whole group of RSA women compared with fertile controls (P: = 0.007). When studying the prognostic value of HLA genotyping for pregnancy outcome (n = 41), 31 patients (76%) gave birth to a living child without performing immunotherapy. Seven out of 10 (70%) couples suffering from a further RSA carried the HLA-G*01013 or *0105N allele, compared with 10 out 31 (32%) couples giving birth (P: = 0.06). This study suggests that the HLA-G genotype may be a contributing factor in RSA.

Abortion, Habitual↗

Activation of mouse oocytes requires multiple sperm factors but not sperm PLCgamma1.

A sperm cytosolic factor is responsible for oocyte activation at fertilization in mammals. The molecular identity of this factor is not yet known, although a sperm phospholipase Cgamma (PLCgamma) is a potential candidate. In this study, cation-exchange chromatography with a Heparin column was used for the fractionation of porcine sperm cytosolic extracts. Oocyte activation potential of the resulting fractions was tested and active fractions were subjected to Western blot analysis using antibodies specific to PLCgamma1. PLCgamma1 was detected in fractions other than those supporting oocyte activation (Ca(2+)-release and pronuclear formation). The active Heparin fraction was then purified on a Mono Q anion-exchange column. One of the resulting fractions still contained Ca(2+)-releasing activity, but pronuclear formation did not occur. We conclude that sperm PLCgamma1 is not involved in oocyte activation and that Ca(2+)-release and pronuclear formation requires multiple factors from sperm cytosol.

Animals↗

Soluble HLA levels in early pregnancy after in vitro fertilization.

Intact pregnancy can be interpreted as a state of maternal immunotolerance toward an haploidentical fetus. Soluble HLA (sHLA) molecules increase during episodes of allograft rejection and are discussed as candidates to modulate immune responses. We questioned whether after in vitro fertilization (IVF) the subsequent intact pregnancy, early abortion, or tubal pregnancy influence the courses sHLA serum levels. Therefore, serum samples of 65 IVF patients were assayed by ELISA for sHLA-I, sHLA-G, and sHLA-DR concentrations preovulatorily and after a positive HCG test weekly until the 9th gestational week (GW). In 20 patients experiencing an early abortion the preovulatory sHLA-G mean level of 25.9 +/- 3.9 SEM ng/ml and the share of 4.2 +/- 0.8 SEM % on total sHLA-I were significantly (p < 0.05) reduced compared to women with intact pregnancy. The same differences (p < 0.0001) were seen during the monitoring of sHLA-G and sHLA-I levels in intact pregnancy versus early abortion until 9th GW. Twin pregnancy revealed a drastically increase of sHLA-G levels from the 8th GW compared to singleton pregnancies. Further, individual sHLA-DR levels increased during intact pregnancy but decreased in the group of early abortion. With regard to sensitivity and specificity for pregnancy outcome sHLA quantitation reached similar weight as routine HCG determinations at GW 5. Especially women with preovulatory low sHLA-G levels appear to be on risk for early abortion after IVF.

Abortion, Spontaneous↗