Biomedical subjects

K Diedrich

Publications and source records attributed to K Diedrich.

At least 55 records · Page 3Linked to original sources

PubMed2004

Reference values of fetal ductus venosus, inferior vena cava and hepatic vein blood flow velocities and waveform indices during the second and third trimester of pregnancy.

OBJECTIVE: Our objective was to establish reference values for ductus venosus, inferior vena cava and hepatic vein flow velocities during ventricular systole (S-wave) and diastole (D-wave), the lowest forward velocity during atrial contraction (a-wave), the intensity-weighted mean flow velocity (Vmean) and different calculated indices. METHODS: Venous flow velocity waveforms were obtained from 329 singleton pregnancies at 20-42 weeks of gestation by pulsed-wave color Doppler. Reference values were constructed by means of a quadratic regression model after logarithmic transformation of original data. RESULTS: With advancing gestational age the peak velocity index for the vein (PVIV) and pulsatility index for the vein (PIV) decreased whereas blood flow velocities increased. Blood flow velocities were highest in the ductus venosus and lowest in the right hepatic vein. Values for PVIV and PIV were highest in the hepatic vein and lowest in the ductus venosus. During atrial contraction there was a blood flow towards the fetal heart in the ductus venosus, whereas in the inferior vena cava and in the hepatic vein blood flow was either in the opposite from the fetal heart (reverse flow), or there was absent flow (zero flow) or flow was towards the fetal heart (positive flow). CONCLUSIONS: The reference ranges and calculated velocities established in this study may be utilized in studies dealing with the role of ductus venosus and inferior vena cava blood flow in fetuses with chromosomal abnormalities or congenital heart disease as well as hypoxic conditions. We speculate, that the reduction in PVIV and PIV with advancing gestational age may reflect a decrease in cardiac afterload as a result of maturation of diastolic ventricular function.

Blood Flow Velocity↗

PubMed2004

Triptorelin versus cetrorelix in intracytoplasmic sperm injection cycles in women with a single ovary.

OBJECTIVE: To compare the response to ovarian stimulation with either the long protocol of a GnRH-agonist or the multiple protocol of a GnRH-antagonist, in women with a single ovary who underwent intracytoplasmic sperm injection (ICSI) cycles. STUDY DESIGN: Retrospective study including 75 ICSI cycles from 26 women. Sixty-three cycles were stimulated with triptorelin/hMG or rFSH, whereas 12 cycles were stimulated with cetrorelix/hMG or rFSH. RESULTS: There was not found any statistical significant difference between the two groups regarding the days of stimulation, the number of gonadotropins' ampoules, the peak estradiol levels, the number of aspirated follicles and the number of retrieved oocytes. The fertilization rate, the number of transferred embryos as well as the cumulative embryo score were also similar in both groups. CONCLUSION: The multiple stimulation protocol of cetrorelix is equally effective with the long protocol of triptorelin in the ovarian stimulation of women with a single ovary.

Adult↗

PubMed2004

Gonadotropin releasing hormone antagonists and cryopreservation outcome: a review.

REVIEW: The outcome of freeze-thaw cycles with pronuclear stage oocytes or embryos, derived from collecting cycles stimulated with gonadotropin-releasing hormone (GnRH)-antagonists' protocols, was reviewed. CONCLUSION: The viability of cryopreserved pronuclear stage oocytes and embryos, the quality of transferred embryos and the pregnancy rates of the freeze-thaw cycles seem to be satisfactory regardless of the type and dose of GnRH-antagonist.

Cryopreservation↗

PubMed2004

Different preferences for prenatal diagnosis in pregnancies following assisted reproduction versus spontaneous conception.

The uptake of prenatal diagnosis in 436 singleton and 146 twin pregnancies following assisted reproduction was compared with a matched group of spontaneous conceptions. The first and second trimester ultrasound examination included target fetal anatomic evaluation and screening by specific markers described for fetal aneuploidy. Women with assisted conception attended significantly more often for first trimester prenatal diagnosis (57.9 versus 34.9%, P < 0.01), but had fewer examinations in the early second trimester at 15-18 weeks (37.8 versus 48.8%, P < 0.01) than those with spontaneous conception. Screen positive results of 6.5 and 6.9% for first trimester examination and 6.0 and 7.3% for second trimester examination were found in assisted conceptions and controls respectively. A significantly higher rate of invasive prenatal diagnosis was observed in the second trimester for spontaneous conceptions, 20.0 versus 11.8% (P < 0.01) compared with assisted conceptions. This was attributed to the higher rate of invasive procedures in advanced maternal age >/=35 years of 40.7 versus 28.6% (P = 0.01) in spontaneous and assisted conceptions respectively. With the purpose of avoiding invasive testing, women with assisted conception were more likely to use the results of the ultrasound examination to guide their final decision about invasive testing, rather than undergo genetic amniocentesis as a first option.

Amniocentesis↗

PubMed2004

Cumulative pregnancy rates and drop-out rates in a German IVF programme: 4102 cycles in 2130 patients.

Cumulative pregnancy rates are useful in counselling couples on their chance of conceiving during infertility treatment. Patients also have to be counselled about the physical and psychological stress of infertility treatment. Beside the pregnancy rates, drop-out rates are a direct, and may be the most important, marker of physician quality in an IVF programme. Data from 4102 IVF cycles in 2130 patients in Germany were analysed retrospectively. Data were analysed using descriptive statistics as well as the Kaplan-Meier procedure. A real cumulative pregnancy rate of 31.2% was achieved after four cycles with an expected cumulative pregnancy rate (ECPR) of 53.3%. Age was a significant factor regarding pregnancy rates (ECPR after four cycles: 57.1% <35 years, 44.8% > or =35 years, 35.4% > or =40 years). The drop-out rate of non-pregnant patients increased from 39.9% after the first cycle to 62.2% after the fourth cycle, indicating the enormous stress and frustration that increased during the course of treatment. The drop-out rate should be used as an important marker of quality control. The presented data give, for the first time, a good basis for this counselling procedure in Germany.

Adult↗

PubMed2004

Low-level gonosomal mosaicism in women undergoing ICSI cycles.

PURPOSE: Females with low-level gonosomal mosaicism (LLGM) scheduled for ICSI were retrospectively analyzed and compared to control groups. The prevalence of this mosaicism as well as its impact for an ICSI treatment were evaluated. METHODS: Routine cytogenetic analysis was done in 891 females scheduled for ICSI treatment. For comparison 294 females with recurrent abortions and 104 women with clinical or cytogenetical affected children, who also had routine chromosome analysis, were acquired. RESULTS: In the ICSI group the incidence of LLGM was significantly lower compared to the group of females with recurrent abortions (3.9% vs. 8.5%, p < 0.01). The incidence was similar between the groups of ICSI females and females with cytogenetical or clinically affected children (5.8%, p = 0.43). Neither anamnestic factors nor outcome parameters were different between females with and without LLGM undergoing ICSI. CONCLUSION: There is no higher incidence of LLGM in females undergoing ICSI. In those who show LLGM, fertility capacity is not reduced.

Abortion, Habitual↗

PubMed2004

FSH time-concentration profiles before and after administration of 0.25 mg cetrorelix in the gnRH-antagonist multiple-dose protocol for ovarian hyperstimulation.

PURPOSE: To determine FSH concentration behavior before and after cetrorelix 0.25 mg administration in the GnRH-antagonist multiple-dose protocol on day 6 of ovarian stimulation with 150-300 IU daily recombinant FSH. METHODS: Blood samples for FSH measurements were drawn from seven women every 15 min from 8 h prior to the first cetrorelix administration in the GnRH-antagonist multiple-dose protocol until 15-32 h thereafter. RESULTS: No significant change of FSH concentration was observed. CONCLUSIONS: This observation indicates that no rationale exists of increasing the daily FSH dosage concomitantly to the GnRH-antagonist administration to compensate for a drop of endogenous FSH.

Biomarkers↗

PubMed2004

[Attitudes toward oocyte donation and surrogate motherhood are strongly influenced by own experiences].

The aim of the study was to find out the attitudes of different groups towards technologies which are prohibited by the German Embryo Protection Law. We evaluated by using a questionnaire, in how far oocyte donation and surrogate motherhood were accepted in Germany in different groups of the population. 34 infertile patients, 74 patients who asked for preimplantation genetic diagnosis (PID), 29 women, who had finished family planning, and 59 medical students were asked for their opinion in a standardized and closed questionnaire. Overall the different groups, especially medical students, were very critical towards oocyte donation and surrogate motherhood. However, to help another couple to conceive a child 68.6 % of PID patients, 62.1 % of infertile patients, 43.2 % of women with finished family planning, and 47.6 % of students were prepared to donate oocytes. On the other hand, only 40.9 %, 40.0 %, 25.9 %, and 13.2 % of PID patients, infertile patients, women with finished family planning and medical students, respectively, would accept oocyte donation for themselves. Regarding surrogate motherhood, the PID group and students were strictly against the idea to be a surrogate mother by themselves. Members of the infertile group as well as those women with finished family planning were more indifferent regarding this question. Students and women with finished family planning, however, would prefer adoption, whilst PID- and infertility groups are more indifferent. Men are more positive towards both techniques as compared to women. As compared to known data from other countries, the acceptance of oocyte donation in all groups and surrogate motherhood is comparable to other European countries, when only PID patients and infertile patients are respected. The other two groups are more critical against surrogate motherhood. To conclude, it becomes apparent how opinions regarding these techniques are influenced by the own situation and experiences.

Adoption↗

PubMed2004

[Induction of labour at term with misoprostol: an effective, safe and inexpensive alternative].

Misoprostol is a prostaglandin E1 analogue marketed for use in the prevention of peptic ulcer disease. It is inexpensive and has few side-effects. Although not registered misoprostol has been widely used for obstetric and gynaecologic indications, such as induction of labour at term. In our clinic misoprostol has been use since April 15, 2003. The data of 70 women, who had been treated with misoprostol for induction of labour at term form April 15 to August 15, 2003, were analysed retrospectively and compared with the data of those women treated with dinoprostin in the same period 2002. The time to active labour was longer with dinoprostin compared to misoprostol (19.2 h vs. 15.5 h). Parity did not influence the time to active labour. The rate of cesarean sections was lower with misoprostol (17.2 vs. 25.8 %). The induction of labour with Misoprostol caused costs of 58.80 euro. If dinoprostin had been used, it would have cost 4 368.00 euro. Although not registered, misoprostol is a safe, effective and inexpensive alternative for induction of labour with few side-effects. However, patients accept the off-label use.

Dinoprostone↗

PubMed2004

Taxanes in the first-line chemotherapy of metastatic breast cancer: review.

Taxanes belong to the most effective agents in the treatment of advanced and non-hormone responsive breast cancer. Several recently published phase III studies have examined the role of taxane-anthracycline combinations in the first line treatment of metastatic breast cancer. Especially, patients with symptomatic visceral spread seem to benefit from taxanes containing polychemotherapy that is adequately dosed. Polychemotherapy with taxanes appears to be more effective than monotherapy. But at present, there are no adequate data concerning the comparison of taxane-monotherapy and anthracycline-containing polychemotherapy. New hopeful results with respect to efficacy and toxicity are reported from the docetaxel-capecitabine polychemotherapy. Thus, the combination of anthracyclines (adriamycin, doxorubicin) and taxanes (docetaxel, paclitaxel) is a promising tool in the treatment of metastatic breast cancer. New interesting combinations are under investigation.

Anthracyclines↗

PubMed2004

The use of cryopreserved mature and immature spermatozoa in assisted reproduction.

Treatment of severe male subfertility has become available since the intracytoplasmic injection of a single sperm into an oocyte was successfully applied for the first time in 1992. Moreover, with the use of fresh and cryopreserved epididymal and testicular spermatozoa for this procedure, fertilization and pregnancies could be accomplished. This review addresses the development and performance of these techniques and discusses achievements and problems as well as future aspects of the feasibility of early spermatid injection. Furthermore, limitations of these procedures and concerns with regard to genetic and epigenetic risks of using immature gametes are discussed.

Cryopreservation↗

PubMed2003

Reference values of ductus venosus blood flow velocities and waveform indices from 10 to 20 weeks of gestation.

OBJECTIVE: Our objective was to establish reference values for ductus venosus flow velocities during ventricular systole (S wave) and diastole (D wave), the lowest forward velocity during atrial contraction (A wave) and different calculated indices [(S-A)/D), (S-A)/Vmean, (S-A)/S, S/A, S/D)]. METHODS: Ductus venosus flow velocity waveforms were obtained from 329 singleton pregnancies at 10-20 weeks of gestation by pulsed-wave color Doppler. Reference values were constructed by means of a quadratic regression model after logarithmic transformation of original data. RESULTS: A significant increase in blood flow velocity during atrial contraction [A-wave, (3.5 cm/s to 9.9 cm/s and 12.9 cm/s to 66.3 cm/s respectively, 5-95% centile)], during ventricular systole [S-wave, (19.2 cm/s to 30.1 cm/s and 45.1 cm/s to 84.9 cm/s respectively, 5-95% centile)] and during early ventricular diastole [D-wave, (15.7 cm/s to 26.1 cm/s and 37.9 cm/s to 77.9 cm/s respectively, 5-95% centile)]. The venous indices values decreased with increasing gestational age. In 3 of 329 fetuses (0.91%) a reversed flow during atrial contraction was seen. CONCLUSION: Assessment of ductus venosus blood flow velocities during first and second trimester is feasible by means of color Doppler flow. The reference ranges and calculated velocities established in this study may be utilized in studies dealing with the role of ductus venosus blood flow in chromosomal abnormal fetuses, fetuses with congenital heart disease or fetal myocardial insufficiency of hypoxic origin.

Adolescent↗

PubMed2003

Effects of insulin on luteinizing hormone and prolactin secretion and calcium signaling in female rat pituitary cells.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is associated with insulin resistance and hyperinsulinemia, which might contribute to the hypersecretion of luteinizing hormone (LH). Hyperprolactinemia is another finding in a subgroup of patients with PCOS, whereas its relation to hyperinsulinemia is not fully understood yet. METHODS: In the present study we tested the hypothesis that insulin might affect LH or prolactin secretion of cultured female rat pituitary cells. To address the mechanisms by which insulin could act at the intracellular level we examined the GnRH- and TRH-induced Ca(2+) signals in single gonadotrophs and lactotrophs, because Ca(2+) is an important component of GnRH signal transduction that is closely related to exocytosis. RESULTS: Cells treated for 24 h with insulin (10(-9) M) showed an enhancement of basal and agonist-induced LH and prolactin secretion. Insulin did not affect GnRH- and TRH-induced Ca(2+) signals compared to controls. There were no differences neither in the frequency nor in the amplitude of the Ca signal. CONCLUSION: Our findings suggest that insulin might contribute to LH hypersecretion. Insulin might be partially responsible for hyperprolactinemia. Since insulin did not affect Ca signaling, other components of the GnRH signal transduction pathway might be involved in LH hypersecretion.

Animals↗

PubMed2003

A comparison of the ovarian response to external stimulation between women with right or left ovary participating in programs of ICSI/ET.

INTRODUCTION: Single ovary women compose a group of special interest in assisted reproduction technologies. The aim of the present study was to investigate whether the response to external stimulation and the outcome in women with a single ovary was affected by the location of the ovary. METHODS: Sixty cycles from 24 women, which stimulated with either hMG or rFSH and a GnRH agonist, were retrospectively studied. Twelve women had right and 12 had left ovary. In all cases, the fertilization was performed by intracytoplasmic sperm injection. RESULTS: There was not found any statistical significant difference between the two groups regarding the days of stimulation, the peak estradiol levels, the number of aspirated follicles, the number of retrieved oocytes, the fertilization rate and the number of transferred embryos. The cumulative embryo score (CES) was also similar in both groups. Six pregnancies in the group of the right ovary and seven in the group of left ovary were achieved. CONCLUSION: According to these results, right and left ovary, in single ovary women under external stimulation, are equally active and potent for reproduction.

Adult↗

PubMed2003

VEGF-, KIT protein- and neutral endopeptidase (NEP/CD10)-positive myofibroblasts-precursors of angiogenesis in chorioangiomas?

Chorioangiomas are benign angiomatous tumours of the placenta occurring with a frequency of approximately one per cent of all examined placentae. Hypoxia and genetic factors are discussed to be predisposing factors for chorioangiomas. However, not much is known about the tumorigenesis of these benign tumours. Screening with various antibodies in a rare case of chorangiomatosis, we found disseminated spindle cells coexpressing vascular epithelial growth factor (VEGF), neutral endopeptidase 24.11 (NEP/CD10), and KIT protein (CD117) within the tumour stroma. A possible involvement of such factors in angiogenesis and tumorigenesis of chorioangiomas/chorangiomatosis has not been studied so far.Seven placentae with chorioangiomas (n=6) or chorangiomatosis (n=1), six normal placentae, and four cutaneous haemangiomas were analysed immunohistochemically (ABC and APAAP methods) using antibodies against VEGF, NEP, KIT protein, as well as endothelial markers like PECAM-1 (CD31), CD34, v. Willebrand factor (factor VIII), and ulex europaeus. In addition, analysis of c-kit 'gain of function' mutation Asp 816 to Val by means of Hinfl digestion and direct sequencing of semi-nested polymerase chain reaction products was performed. All chorioangiomas and haemangiomas strongly expressed the endothelial markers CD34, CD31, and FVIII, while only weak expression of ulex lectin was noted. Disseminated groups of VEGF-, NEP-, and KIT protein-positive spindle cells, which coexpressed vimentin and smooth-muscle actin were identified as myofibroblasts in the stroma of four chorioangiomas. These spindle cells were quantified as numerous in two and as rare in two other cases. No VEGF-positive myofibroblasts, however, were detected in the villous stroma of normal control placentae and haemangiomas. Only scattered perivascular myofibroblasts expressing KIT protein and NEP were detected in early gestational placenta controls. In all chorioangiomas and chorangiomatosis PCR analysis failed to unveil c-kit 'gain of function' mutation Asp 816 to Val in KIT protein-positive spindle cells. Moreover, a significant increase in mast cells was observed only in the haemangiomas. As expected, endothelial origin of chorioangiomas/chorangiomatosis was verified by CD31, CD34, FVIII expression. Myofibroblastic spindle cells expressing VEGF and NEP may be precursor cells in these peculiar angiomatous tumours. Although activating c-kit mutation Asp 816 to Val was not detected by PCR, the presence of KIT protein (CD117)-positive intratumoral myofibroblastic spindle cells in chorioangiomas and chorangiomatosis might suggest involvement of the stem cell factor (SCF)-receptor in pathologically enhanced angiogenesis.

Adult↗

PubMed2003

The activation of an extracellular signal-regulated kinase by oestradiol interferes with the effects of trastuzumab on HER2 signalling in endometrial adenocarcinoma cell lines.

Cellular response to oestradiol stimuli is mediated both by oestrogen receptor (ER) binding to oestrogen response elements (EREs) and by non-nuclear actions like activation of mitogen-activated protein kinase (MAPK) signal transduction. Therefore, oestradiol stimuli might be able to interfere with the action of antitumoral substances directed against receptor tyrosine kinase signalling. We investigated the effect of oestradiol on the inhibition of HER2 signalling by trastuzumab (Herceptin) in two human endometrial adenocarcinoma cell lines. Activation of the extracellular signal-regulated kinase (ERK-1/2), a major mediator of HER2 signalling, was measured by means of western blotting experiments and ERE activation was determined in transient reporter-gene assays. In endometrial Ishikawa and HEC-1A adenocarcinoma cells, HER2 signalling was inhibited by trastuzumab only in the absence of oestradiol. We were able to demonstrate that oestradiol counteracted the inhibitory effects of trastuzumab by rapid phosphorylation of ERK-1/2, a kinase downstream of the HER2 receptor. The pure anti-oestrogen ICI 182,780 was able to restore both the trastuzumab-triggered inhibition of the ERK-1/2 pathway and the antiproliferative action of this substance in Ishikawa cells. Our data suggest that combinations of trastuzumab with anti-oestrogens may be effective in the treatment of endometrial cancers with a positive ER and HER2 receptor status.

Adenocarcinoma↗

PubMed2003

The diagnostic dilemma of minimal and mild endometriosis under routine conditions.

STUDY OBJECTIVE: To evaluate the reliability of diagnosing minimal and mild endometriosis under routine conditions, and to determine to what extent disease activity is taken into account. DESIGN: Retrospective analysis (Canadian Task Force classification II-2). SETTING: University teaching hospital. INTERVENTION: Laparoscopy. PATIENTS: One hundred eighteen consecutive women with minimal and mild endometriosis undergoing routine surgery between 1994 and 1999. MEASUREMENTS AND MAIN RESULTS: Analytic parameters were the total number of endometriotic lesions; intraoperative description of pigmented, nonpigmented, and nondefined lesions; and number of extirpated lesions and histologic detection rate. In 118 patients, 311 suspected endometriotic lesions were documented. Nonpigmented lesions were reported in only 27% of women. In 51% of surgical reports no importance was attached to disease morphology or activity. Only 1.2 biopsies/patient were taken. The histologic detection rate was 56%. In 49 patients the assumed intraoperative diagnosis was confirmed by histologic examination. CONCLUSIONS: Intraoperative description of endometriotic lesions is inadequate. Little attention is paid to the activity of the illness. There is room for improvement in the number of excisions and histologic detection, and an attempt should be made to find a way out of this diagnostic dilemma.

Adult↗

PubMed2003

Safety and efficacy of a 3 mg dose of the GnRH antagonist cetrorelix in preventing premature LH surges: report of two large multicentre, multinational, phase IIIb clinical experiences.

Gonadotrophin-releasing hormone antagonists are effective and safe in preventing premature LH surges, a leading cause of cycle cancellation or failure during assisted conception. Two studies assessed two administration regimens for cetrorelix (as Cetrotide): the multiple-dose (MD, 0.25 mg/day, n = 1066) and single-dose (SD, 3 mg, n = 541) protocols. Patient outcomes were very similar: >90% reached criteria for human chorionic gonadotrophin (HCG) administration and underwent oocyte retrieval; embryo transfer was performed in 83-84%; failure to retrieve oocytes was rare (0.8%); on average, 11 follicles > or =10 mm in diameter were seen on the day of HCG administration. The SD protocol was associated with higher numbers of oocytes retrieved and available for insemination, although the numbers of embryos obtained or transferred were comparable. A total of 251 and 121 pregnancies were reported in the MD and SD groups respectively. Pregnancy rates per embryo transfer were 27 and 28% respectively. Severe ovarian hyperstimulation syndrome (OHSS) occurred in <1% of cycles. Twelve per cent of patients reported local reactions to injections in the MD group, compared with 8% in the SD group; none was serious or led to discontinuation. Seventy-three per cent of patients in the SD group received only one injection. These two studies therefore show that the single-dose cetrorelix protocol offers equal efficacy and safety to the MD regimen, while having the advantage of requiring only one injection in most patients.

Adult↗